Sample records for krp1 sarcosin promotes

  1. The glycine transport inhibitor sarcosine is an inhibitory glycine receptor agonist.

    PubMed

    Zhang, Hai Xia; Lyons-Warren, Ariel; Thio, Liu Lin

    2009-01-01

    Sarcosine is an endogenous amino acid that is a competitive inhibitor of the type I glycine transporter (GlyT1), an N-methyl-d-aspartate receptor (NMDAR) co-agonist, and an important intermediate in one-carbon metabolism. Its therapeutic potential for schizophrenia further underscores its clinical importance. The structural similarity between sarcosine and glycine and sarcosine's ability to serve as an NMDAR co-agonist led us to examine whether sarcosine is also an agonist at the inhibitory glycine receptor (GlyR). We examined this possibility using whole-cell recordings from cultured embryonic mouse hippocampal neurons and found that sarcosine evoked a dose-dependent, strychnine sensitive, Cl(-) current that cross-inhibited glycine currents. Sarcosine evoked this current with Li(+) in the extracellular solution to block GlyT1, in neurons treated with the essentially irreversible GlyT1 inhibitor N[3-(4'-fluorophenyl)-3-(4'-phenylphenoxy)propyl]sarcosine (NFPS), and in neurons plated in the absence of glia. These results indicate that the sarcosine currents did not result from GlyT1 inhibition or heteroexchange. We conclude that sarcosine is a GlyR agonist.

  2. The Glycine Transport Inhibitor Sarcosine Is an Inhibitory Glycine Receptor Agonist

    PubMed Central

    Zhang, Hai Xia; Lyons-Warren, Ariel; Thio, Liu Lin

    2009-01-01

    Summary Sarcosine is an endogenous amino acid that is a competitive inhibitor of the type I glycine transporter (GlyT1), an N-methyl-D-aspartate receptor (NMDAR) co-agonist, and an important intermediate in one-carbon metabolism. Its therapeutic potential for schizophrenia further underscores its clinical importance. The structural similarity between sarcosine and glycine and sarcosine's ability to serve as an NMDAR co-agonist led us to examine whether sarcosine is also an agonist at the inhibitory glycine receptor (GlyR). We examined this possibility using whole-cell recordings from cultured embryonic mouse hippocampal neurons and found that sarcosine evoked a dose-dependent, strychnine sensitive, Cl- current that cross-inhibited glycine currents. Sarcosine evoked this current with Li+ in the extracellular solution to block GlyT1, in neurons treated with the essentially irreversible GlyT1 inhibitor N[3-(4′-fluorophenyl)-3-(4′-phenylphenoxy)propyl]sarcosine (NFPS), and in neurons plated in the absence of glia. These results indicate that the sarcosine currents did not result from GlyT1 inhibition or heteroexchange. We conclude that sarcosine is a GlyR agonist. PMID:19619564

  3. Transport and metabolism of sarcosine in hypersarcosinemic and normal phenotypes

    PubMed Central

    Glorieux, Francis H.; Scriver, Charles R.; Delvin, Edgard; Mohyuddin, Fazl

    1971-01-01

    An adolescent male proband with hypersarcosinemia was discovered incidentally in a French-Canadian family; no specific disease was associated with the trait. The hypersarcosinemia is not diminished by dietary folic acid even in pharmacologic doses (30 mg/day). The normal absence of sarcosine dehydrogenase in cultured human skin fibroblasts and in leukocytes was confirmed, thus eliminating these tissues as useful sources for further investigation of mutant sarcosinemic phenotypes and genotypes. The response in plasma of sarcosine and glycine, after sarcosine loading, distinguished the normal subject from the subjects who were presumably homozygous and heterozygous for the hypersarcosinemia allele. Sarcosine clearance from plasma was delayed greatly (t½, 6.1 hr) in the presumed homozygote and slightly (t½, 2.2 hr) in the presumed heterozygote, while plasma glycine remained constant in the former and rose in the latter. Normal subjects clear sarcosine from plasma rapidly (t½, 1.6 hr) while their plasma glycine trend is downward. The phenotypic responses suggest that hypersarcosinemia is an autosomal recessive trait in this pedigree. Renal tubular transport of sarcosine was normal in the proband even though he presumably lacked the sarcosine oxidation which should normally occur in kidney. Sarcosine catabolism is thus not important for its own renal uptake. Sarcosine interacts with proline and glycine during its absorption in vivo. Studies in vitro in rat kidney showed that sarcosine transport is mediated, saturable, and energy dependent. Sarcosine has no apparent transport system of its own; it uses the low Km transport systems for L-proline and glycine to a minor extent and a high Km system shared by these substances for the major uptake at concentrations encountered in hypersarcosinemia. Intracellular sarcosine at high concentration will exchange with glycine on one of these systems, which may explain a paradoxical improvement in renal transport of glycine after

  4. NtKRP, a kinesin-12 protein, regulates embryo/seed size and seed germination via involving in cell cycle progression at the G2/M transition.

    PubMed

    Tian, Shujuan; Wu, Jingjing; Li, Fen; Zou, Jianwei; Liu, Yuwen; Zhou, Bing; Bai, Yang; Sun, Meng-Xiang

    2016-10-25

    Kinesins comprise a superfamily of microtubule-based motor proteins involved in essential processes in plant development, but few kinesins have been functionally identified during seed development. Especially, few kinesins that regulate cell division during embryogenesis have been identified. Here we report the functional characterization of NtKRP, a motor protein of the kinesin-12 family. NtKRP is predominantly expressed in embryos and embryonic roots. NtKRP RNAi lines displayed reductions in cell numbers in the meristematic zone, in embryonic root length, and in mature embryo and seed sizes. Furthermore, we also show that CDKA;1 binds to NtKRP at the consensus phosphorylation sites and that the decreased cell numbers in NtKRP-silenced embryos are due to a delay in cell division cycle at the G2/M transition. In addition, binding between the cargo-binding tail domain of NtKRP and CDKA; 1 was also determined. Our results reveal a novel molecular pathway that regulates embryo/seed development and critical role of kinesin in temporal and spatial regulation of a specific issue of embryo developmental.

  5. Ribosomal protein NtRPL17 interacts with kinesin-12 family protein NtKRP and functions in the regulation of embryo/seed size and radicle growth.

    PubMed

    Tian, Shujuan; Wu, Jingjing; Liu, Yuan; Huang, Xiaorong; Li, Fen; Wang, Zhaodan; Sun, Meng-Xiang

    2017-11-28

    We previously reported that a novel motor protein belonging to the kinesin-12 family, NtKRP, displays critical roles in regulating embryo and seed size establishment. However, it remains unknown exactly how NtKRP contributes to this developmental process. Here, we report that a 60S ribosomal protein NtRPL17 directly interacts with NtKRP. The phenotypes of NtRPL17 RNAi lines show notable embryo and seed size reduction. Structural observations of the NtRPL17-silenced embryos/seeds reveal that the embryo size reduction is due to a decrease in cell number. In these embryos, cell division cycle progression is delayed at the G2/M transition. These phenotypes are similar to that in NtKRP-silenced embryos/seeds, indicating that NtKRP and NtRPL17 function as partners in the same regulatory pathway during seed development and specifically regulate cell cycle progression to control embryo/seed size. This work reveals that NtRPL17, as a widely distributed ribosomal protein, plays a critical role in seed development and provides a new clue in the regulation of seed size. Confirmation of the interaction between NtKRP and NtRPL17 and their co-function in the control of the cell cycle also suggests that the mechanism might be conserved in both plants and animals. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  6. An electrochemiluminescence-supramolecular approach to sarcosine detection for early diagnosis of prostate cancer.

    PubMed

    Valenti, Giovanni; Rampazzo, Enrico; Biavardi, Elisa; Villani, Elena; Fracasso, Giulio; Marcaccio, Massimo; Bertani, Federico; Ramarli, Dunia; Dalcanale, Enrico; Paolucci, Francesco; Prodi, Luca

    2015-01-01

    Monitoring Prostate Cancer (PCa) biomarkers is an efficient way to diagnosis this disease early, since it improves the therapeutic success rate and suppresses PCa patient mortality: for this reason a powerful analytical technique such as electrochemiluminescence (ECL) is already used for this application, but its widespread usability is still hampered by the high cost of commercial ECL equipment. We describe an innovative approach for the selective and sensitive detection of the PCa biomarker sarcosine, obtained by a synergistic ECL-supramolecular approach, in which the free base form of sarcosine acts as co-reagent in a Ru(bpy)3(2+)-ECL process. We used magnetic micro-beads decorated with a supramolecular tetraphosphonate cavitand (Tiiii) for the selective capture of sarcosine hydrochloride in a complex matrix like urine. Sarcosine determination was then obtained with ECL measurements thanks to the complexation properties of Tiiii, with a protocol involving simple pH changes - to drive the capture-release process of sarcosine from the receptor - and magnetic micro-bead technology. With this approach we were able to measure sarcosine in the μM to mM window, a concentration range that encompasses the diagnostic urinary value of sarcosine in healthy subjects and PCa patients, respectively. These results indicate how this ECL-supramolecular approach is extremely promising for the detection of sarcosine and for PCa diagnosis and monitoring, and for the development of portable and more affordable devices.

  7. Physical Intrepretation of Mathematically Invariant K(r,P) Type Equations of State for Hydrodynamically Driven Flow

    NASA Astrophysics Data System (ADS)

    Hrbek, George

    2001-06-01

    At SCCM Shock 99, Lie Group Theory was applied to the problem of temperature independent, hydrodynamic shock in a Birch-Murnaghan continuum. (1) Ratios of the group parameters were shown to be linked to the physical parameters specified in the second, third, and fourth order BM-EOS approximations. This effort has subsequently been extended to provide a general formalism for a wide class of mathematical forms (i.e., K(r,P)) of the equation of state. Variations in material expansion and resistance (i.e., counter pressure) are shown to be functions of compression and material variation ahead of the expanding front. Specific examples included the Birch-Murnaghan, Vinet, Brennan-Stacey, Shanker, Tait, Poirier, and Jones-Wilkins-Lee (JWL) forms. (2) With these ratios defined, the next step is to predict the behavior of these K(r,P) type solids. To do this, one must introduce the group ratios into a numerical simulation for the flow and generate the density, pressure, and particle velocity profiles as the shock moves through the material. This will allow the various equations of state, and their respective fitting coefficients, to be compared with experiments, and additionally, allow the empirical coefficients for these EOS forms to be adjusted accordingly. (1) Hrbek, G. M., Invariant Functional Forms For The Second, Third, And Fourth Order Birch-Murnaghan Equation of State For Materials Subject to Hydrodynamic Shock, Proceedings of the 11th American Physical Society Topical Group Meeting on Shock Compression of Condensed Matter (SCCM Shock 99), Snowbird, Utah (2) Hrbek, G. M., Invariant Functional Forms For K(r,P) Type Equations Of State For Hydrodynamically Driven Flows, Submitted to the 12th American Physical Society Topical Group Meeting on Shock Compression of Condensed Matter (SCCM Shock 01), Atlanta, Georgia

  8. Sarcosine influences apoptosis and growth of prostate cells via cell-type specific regulation of distinct sets of genes.

    PubMed

    Rodrigo, Miguel A Merlos; Strmiska, Vladislav; Horackova, Eva; Buchtelova, Hana; Michalek, Petr; Stiborova, Marie; Eckschlager, Tomas; Adam, Vojtech; Heger, Zbynek

    2018-02-01

    Sarcosine is a widely discussed oncometabolite of prostate cells. Although several reports described connections between sarcosine and various phenotypic changes of prostate cancer (PCa) cells, there is still a lack of insights on the complex phenomena of its effects on gene expression patterns, particularly in non-malignant and non-metastatic cells. To shed more light on this phenomenon, we performed parallel microarray profiling of RNA isolated from non-malignant (PNT1A), malignant (22Rv1), and metastatic (PC-3) prostate cell lines treated with sarcosine. Microarray results were experimentally verified using semi-quantitative-RT-PCR, clonogenic assay, through testing of the susceptibility of cells pre-incubated with sarcosine to anticancer agents with different modes of actions (inhibitors of topoisomerase II, DNA cross-linking agent, antimicrotubule agent and inhibitor of histone deacetylases) and by evaluation of activation of executioner caspases 3/7. We identified that irrespective of the cell type, sarcosine stimulates up-regulation of distinct sets of genes involved in cell cycle and mitosis, while down-regulates expression of genes driving apoptosis. Moreover, it was found that in all cell types, sarcosine had pronounced stimulatory effects on clonogenicity. Except of an inhibitor of histone deacetylase valproic acid, efficiency of all agents was significantly (P < 0.05) decreased in sarcosine pre-incubated cells. Our comparative study brings evidence that sarcosine affects not only metastatic PCa cells, but also their malignant and non-malignant counterparts and induces very similar changes in cells behavior, but via distinct cell-type specific targets. © 2017 Wiley Periodicals, Inc.

  9. Sarcosine Up-Regulates Expression of Genes Involved in Cell Cycle Progression of Metastatic Models of Prostate Cancer

    PubMed Central

    Heger, Zbynek; Merlos Rodrigo, Miguel Angel; Michalek, Petr; Polanska, Hana; Masarik, Michal; Vit, Vitezslav; Plevova, Mariana; Pacik, Dalibor; Eckschlager, Tomas; Stiborova, Marie

    2016-01-01

    The effects of sarcosine on the processes driving prostate cancer (PCa) development remain still unclear. Herein, we show that a supplementation of metastatic PCa cells (androgen independent PC-3 and androgen dependent LNCaP) with sarcosine stimulates cells proliferation in vitro. Similar stimulatory effects were observed also in PCa murine xenografts, in which sarcosine treatment induced a tumor growth and significantly reduced weight of treated mice (p < 0.05). Determination of sarcosine metabolism-related amino acids and enzymes within tumor mass revealed significantly increased glycine, serine and sarcosine concentrations after treatment accompanied with the increased amount of sarcosine dehydrogenase. In both tumor types, dimethylglycine and glycine-N-methyltransferase were affected slightly, only. To identify the effects of sarcosine treatment on the expression of genes involved in any aspect of cancer development, we further investigated expression profiles of excised tumors using cDNA electrochemical microarray followed by validation using the semi-quantitative PCR. We found 25 differentially expressed genes in PC-3, 32 in LNCaP tumors and 18 overlapping genes. Bioinformatical processing revealed strong sarcosine-related induction of genes involved particularly in a cell cycle progression. Our exploratory study demonstrates that sarcosine stimulates PCa metastatic cells irrespectively of androgen dependence. Overall, the obtained data provides valuable information towards understanding the role of sarcosine in PCa progression and adds another piece of puzzle into a picture of sarcosine oncometabolic potential. PMID:27824899

  10. Supplementation of antipsychotic treatment with sarcosine – GlyT1 inhibitor – causes changes of glutamatergic (1)NMR spectroscopy parameters in the left hippocampus in patients with stable schizophrenia.

    PubMed

    Strzelecki, Dominik; Podgórski, Michał; Kałużyńska, Olga; Gawlik-Kotelnicka, Oliwia; Stefańczyk, Ludomir; Kotlicka-Antczak, Magdalena; Gmitrowicz, Agnieszka; Grzelak, Piotr

    2015-10-08

    Glutamatergic system, the main stimulating system of the brain, plays an important role in the pathogenesis of schizophrenia. Hippocampus, a structure crucial for memory and cognitive functions and rich in glutamatergic neurons, is a natural object of interest in studies on psychoses. Sarcosine, a glycine transporter (GlyT-1) inhibitor influences the function of NMDA receptor and glutamate-dependent transmission. The aim of the study was to assess the effects of sarcosine on metabolism parameters in the left hippocampus in patients with schizophrenia. Assessments were performed using proton nuclear magnetic resonance ((1)H NMR) spectroscopy (1.5T). Fifty patients diagnosed with schizophrenia (DSM-IV-TR), with dominant negative symptoms, in stable clinical condition and stable antipsychotics doses were treated either with sarcosine (n=25) or placebo (n=25). Spectroscopic parameters were evaluated within groups and between two groups before and after 6-month intervention. All patients were also assessed with the Positive and Negative Syndrome Scale (PANSS). In the sarcosine group, after 6-month treatment, we found significant decrease in hippocampal Glx/Cr (Glx-complex of glutamate, glutamine and GABA, Cr-creatine) and Glx/Cho (Cho-choline), while N-acetylaspartate (NAA), myo-inositol (mI), Cr and Cho parameters remained stable along the study and also did not differ significantly between both groups. This is the first study showing that a pharmacological intervention in schizophrenia, particularly augmentation of the antypsychotic treatment with sarcosine, may reverse the pathological increase in glutamatergic transmission in the hippocampus. The results confirm involvement of glutamatergic system in the pathogenesis of schizophrenia and demonstrate beneficial effects of GlyT-1 inhibitor on the metabolism in the hippocampus and symptoms of schizophrenia. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  11. Antidepressant-like effects of long-term sarcosine treatment in rats with or without chronic unpredictable stress.

    PubMed

    Chen, Kuang-Ti; Wu, Ching-Hsiang; Tsai, Mang-Hung; Wu, Ya-Chieh; Jou, Ming-Jia; Huang, Chih-Chia; Wei, I-Hua

    2017-01-01

    Sarcosine, an N-methyl-d-aspartate receptor enhancer, can improve depression-like behavior in rodent models and depression in humans. We found that a single dose of sarcosine exerted antidepressant-like effects with rapid concomitant increases in the mammalian target of rapamycin (mTOR) signaling pathway activation and enhancement of α-amino-3-hydroxy-5-methylisoxazole-4-propionate receptor (AMPAR) membrane insertion. Sarcosine may play a crucial role in developing novel therapy for depression. For a detailed understanding of sarcosine, this study examined the effects of long-term sarcosine treatment on the forced swim test (FST), mTOR signaling, and AMPAR membrane insertion in rats. The effects of long-term sarcosine treatment were examined in naive rats and rats exposed to chronic unpredictable stress (CUS). Long-term sarcosine treatment (560mg/kg/d for 21 d) significantly ameliorated the increased immobility induced by CUS in the FST, reaffirming the potential role of sarcosine as an antidepressant for depressed patients. The same long-term treatment exhibited no such effect in naive rats despite increased mTOR activation and AMPAR membrane insertion in both groups. Our findings clearly show CUS-exposed rats are sensitive to long-term sarcosine treatment in FST and the response at the same dose is absent in naïve rats. Nevertheless, the distinct sensitivity to long-term sarcosine treatment in rats with or without CUS is not associated with the activated mTOR signaling pathway or increased AMPAR membrane insertion. Additionally, understanding the behavioral and molecular basis of distinct responses is vital important for developing personalized treatment programs to increase the probability of success when treating depression. Copyright © 2016. Published by Elsevier B.V.

  12. Adding Sarcosine to Antipsychotic Treatment in Patients with Stable Schizophrenia Changes the Concentrations of Neuronal and Glial Metabolites in the Left Dorsolateral Prefrontal Cortex.

    PubMed

    Strzelecki, Dominik; Podgórski, Michał; Kałużyńska, Olga; Stefańczyk, Ludomir; Kotlicka-Antczak, Magdalena; Gmitrowicz, Agnieszka; Grzelak, Piotr

    2015-10-15

    The glutamatergic system is a key point in pathogenesis of schizophrenia. Sarcosine (N-methylglycine) is an exogenous amino acid that acts as a glycine transporter inhibitor. It modulates glutamatergic transmission by increasing glycine concentration around NMDA (N-methyl-d-aspartate) receptors. In patients with schizophrenia, the function of the glutamatergic system in the prefrontal cortex is impaired, which may promote negative and cognitive symptoms. Proton nuclear magnetic resonance (¹H-NMR) spectroscopy is a non-invasive imaging method enabling the evaluation of brain metabolite concentration, which can be applied to assess pharmacologically induced changes. The aim of the study was to evaluate the influence of a six-month course of sarcosine therapy on the concentration of metabolites (NAA, N-acetylaspartate; Glx, complex of glutamate, glutamine and γ-aminobutyric acid (GABA); mI, myo-inositol; Cr, creatine; Cho, choline) in the left dorso-lateral prefrontal cortex (DLPFC) in patients with stable schizophrenia. Fifty patients with schizophrenia, treated with constant antipsychotics doses, in stable clinical condition were randomly assigned to administration of sarcosine (25 patients) or placebo (25 patients) for six months. Metabolite concentrations in DLPFC were assessed with 1.5 Tesla ¹H-NMR spectroscopy. Clinical symptoms were evaluated with the Positive and Negative Syndrome Scale (PANSS). The first spectroscopy revealed no differences in metabolite concentrations between groups. After six months, NAA/Cho, mI/Cr and mI/Cho ratios in the left DLPFC were significantly higher in the sarcosine than the placebo group. In the sarcosine group, NAA/Cr, NAA/Cho, mI/Cr, mI/Cho ratios also significantly increased compared to baseline values. In the placebo group, only the NAA/Cr ratio increased. The addition of sarcosine to antipsychotic therapy for six months increased markers of neurons viability (NAA) and neurogilal activity (mI) with simultaneous improvement

  13. Structure and effect of sarcosine on water and urea by using molecular dynamics simulations: Implications in protein stabilization.

    PubMed

    Kumar, Narendra; Kishore, Nand

    2013-01-01

    Sarcosine is one of the most important protecting osmolytes which is also known to counteract the denaturing effect of urea. We used molecular dynamics simulation methods to investigate the mechanism of protein stabilization and counteraction of urea by sarcosine. We found that sarcosine enhanced the tetrahedral structure of water and strengthened its hydrogen bonding network. We also found that sarcosine did not form clusters unlike glycine. Our results show strong interaction between sarcosine and urea molecules. Addition of sarcosine enhanced the urea-water structure and urea-water lifetime indicated an increase in the solvation of urea. These findings suggest that sarcosine indirectly stabilizes protein by enhancing water-water structure thus decreasing the hydrophobic effect and counteracts the effect of urea by increasing the solvation of urea and directly interacting with it leaving urea less available to interact with protein. Copyright © 2012 Elsevier B.V. All rights reserved.

  14. Pharmacology and expression analysis of glycine transporter GlyT1 with [3H]-(N-[3-(4'-fluorophenyl)-3-(4'phenylphenoxy)propyl])sarcosine.

    PubMed

    Mallorga, Pierre J; Williams, Jacinta B; Jacobson, Marlene; Marques, Rosemary; Chaudhary, Ashok; Conn, P Jeffrey; Pettibone, Douglas J; Sur, Cyrille

    2003-10-01

    In the central nervous system, re-uptake of the neurotransmitter glycine is mediated by two different glycine transporters, GlyT1 and GlyT2. GlyT2 is found in brainstem and spinal cord, whereas GlyT1 is expressed in rat forebrain regions where it is responsible for most glycine transport activity. Initially, GlyT1 and GlyT2 were pharmacologically differentiated by sarcosine, a weak selective inhibitor of GlyT1. The recently described selective and potent GlyT1 antagonist, NFPS/ALX-5407 provided an important additional tool to further characterize GlyT1 pharmacology. In the present study, we have radiolabeled the racemic form of NFPS (N-[3-(4'-fluorophenyl)-3-(4'-phenylphenoxy)propyl])sarcosine (also known as ALX-5407) to investigate its interaction with GlyT1, as well as define GlyT1 expression in the rat central nervous system. Kinetic studies indicated that [3H]NFPS binds rapidly to rat forebrain membranes and dissociates with a t(1/2) of 28 +/- 5 min. [3H]NFPS labeled a saturable population of sites in rat forebrain with a Kd of 7.1+/-1.3 nM and a B(max) of 3.14 +/- 0.26 pmol/mg protein. Bound [3H]NFPS was fully and potently displaced by unlabeled NFPS, whereas glycine and sarcosine were weak, Na+-dependent inhibitors with IC50 of 1,008 and 190 microM, respectively. Additional saturation experiments indicated that glycine and sarcosine were non-competitive antagonists of [3H]NFPS binding. Functional studies revealed that NFPS was a non-competitive inhibitor of [3H]glycine uptake and does not interact with Na+ and Cl- binding sites of GlyT1. Overall, this work shows that [3H]NFPS is a valuable tool in studying GlyT1 expression and pharmacology and that NFPS interacts with GlyT1 at a site different from the transporter translocation and ion binding sites.

  15. Hierarchical CuInS2-based heterostructure: Application for photocathodic bioanalysis of sarcosine.

    PubMed

    Jiang, Xin-Yuan; Zhang, Ling; Liu, Yi-Li; Yu, Xiao-Dong; Liang, Yan-Yu; Qu, Peng; Zhao, Wei-Wei; Xu, Jing-Juan; Chen, Hong-Yuan

    2018-06-01

    In this study, on the basis of hierarchical CuInS 2 -based heterostructure, a novel cathodic photoelectrochemical (PEC) enzymatic bioanalysis of the sarcosine detection was reported. Specifically, heterostructured CuInS 2 /NiO/ITO photocathode was prepared and sarcosine oxidases (SOx) were integrated for the construction of the enzymatic biosensor. In the bioanalysis, the O 2 -dependent suppression of the cathodic photocurrent can be observed due to the competition between the as-fabricated O 2 -sensitive photocathode and the SOx-catalytic event toward O 2 reduction. Based on the sarcosine-controlled O 2 concentration, a novel photocathodic enzymatic biosensor could be realized for the sensitive and specific sarcosine detection. This work manifested the great potential of CuInS 2 -based heterostructure as a novel platform for future PEC bioanalytical development and also a PEC method for sarcosine detection, which could be easily extended to numerous other enzymatic systems and to our knowledge has not been reported. This work is expected to stimulate more interest in the design and implementation of numerous CuInS 2 -based heterostructured photocathodic enzymatic sensing. Copyright © 2018 Elsevier B.V. All rights reserved.

  16. Sarcosine attenuates toluene-induced motor incoordination, memory impairment, and hypothermia but not brain stimulation reward enhancement in mice

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chan, Ming-Huan; Institute of Neuroscience, National Changchi University, Taipei, Taiwan; Chung, Shiang-Sheng

    Toluene, a widely used and commonly abused organic solvent, produces various behavioral disturbances, including motor incoordination and cognitive impairment. Toluene alters the function of a large number of receptors and ion channels. Blockade of N-methyl-D-aspartate (NMDA) receptors has been suggested to play a critical role in toluene-induced behavioral manifestations. The present study determined the effects of various toluene doses on motor coordination, recognition memory, body temperature, and intracranial self-stimulation (ICSS) thresholds in mice. Additionally, the effects of sarcosine on the behavioral and physiological effects induced by toluene were evaluated. Sarcosine may reverse toluene-induced behavioral manifestations by acting as an NMDAmore » receptor co-agonist and by inhibiting the effects of the type I glycine transporter (GlyT1). Mice were treated with toluene alone or combined with sarcosine pretreatment and assessed for rotarod performance, object recognition memory, rectal temperature, and ICSS thresholds. Toluene dose-dependently induced motor incoordination, recognition memory impairment, and hypothermia and lowered ICSS thresholds. Sarcosine pretreatment reversed toluene-induced changes in rotarod performance, novel object recognition, and rectal temperature but not ICSS thresholds. These findings suggest that the sarcosine-induced potentiation of NMDA receptors may reverse motor incoordination, memory impairment, and hypothermia but not the enhancement of brain stimulation reward function associated with toluene exposure. Sarcosine may be a promising compound to prevent acute toluene intoxications by occupational or intentional exposure. -- Highlights: ► Toluene induces impairments in Rotarod test and novel object recognition test. ► Toluene lowers rectal temperature and ICSS thresholds in mice. ► Sarcosine reverses toluene-induced changes in motor, memory and body temperature. ► Sarcosine pretreatment does not affect toluene

  17. MMP-9 Serum Levels in Schizophrenic Patients during Treatment Augmentation with Sarcosine (Results of the PULSAR Study).

    PubMed

    Strzelecki, Dominik; Kałużyńska, Olga; Szyburska, Justyna; Wysokiński, Adam

    2016-07-09

    Find changes in matrix metallopeptidase-9 (MMP-9) levels during augmentation of antipsychotic treatment with sarcosine and a relationship between schizophrenia symptoms severity and initial level of MMP-9. Fifty-eight patients with diagnosis of schizophrenia with predominant negative symptoms participated in a six-month prospective RCT (randomized controlled trial). The patients received two grams of sarcosine (n = 28) or placebo (n = 30) daily. At the beginning, after six weeks and after six months MMP-9 levels were measured. Severity of symptomatology was assessed with the Positive and Negative Syndrome Scale (PANSS) and Calgary Depression Scale for Schizophrenia (CDSS). MMP-9 serum levels were stable after six weeks and six months in both groups. We noted improvement in negative symptoms, general psychopathology and total PANSS score in sarcosine group compared to placebo; however, there was no correlations between serum MMP-9 concentrations and PANSS scores in all assessments. Initial serum MMP-9 concentrations cannot be used as an improvement predictor acquired during sarcosine augmentation. Our results indicate that either MMP-9 is not involved in the N-methyl-d-aspartate (NMDA)-dependent mechanism of sarcosine action in terms of clinical parameters or sarcosine induced changes in peripheral MMP-9 concentrations cannot be detected in blood assessments.

  18. Invariant Functional Forms for K(r,P) Type Equations of State for Hydrodynamically Driven Flow

    NASA Astrophysics Data System (ADS)

    Hrbek, George

    2001-06-01

    At the 11th American Physical Society Topical Group Meeting on Shock Compression of Condensed Matter, Group Theoretic Methods, as defined by Lie were applied to the problem of temperature independent, hydrodynamic shock in a Birch-Murnaghan continuum. (1) Group parameter ratios were linked to the physical quantities (i.e., KT, K'T, and K''T) specified for the various order Birch-Murnaghan approximations. This technique has now been generalized to provide a mathematical formalism applicable to a wide class of forms (i.e., K(r,P)) for the equation of state. Variations in material expansion and resistance (i.e., counter pressure) are shown to be functions of compression and material variation ahead of the expanding front. Illustrative examples include the Birch-Murnaghan, Vinet, Brennan-Stacey, Shanker, Tait, Poirier, and Jones-Wilkins-Lee (JWL) forms. The results of this study will allow the various equations of state, and their respective fitting coefficients, to be compared with experiments. To do this, one must introduce the group ratios into a numerical simulation for the flow and generate the density, pressure, and particle velocity profiles as the shock moves through the material. (2) (1) Hrbek, G. M., Invariant Functional Forms For The Second, Third, And Fourth Order Birch-Murnaghan Equation of State For Materials Subject to Hydrodynamic Shock, Proceedings of the 11th American Physical Society Topical Group Meeting on Shock Compression of Condensed Matter (SCCM Shock 99), Snowbird, Utah (2) Hrbek, G. M., Physical Interpretation of Mathematically Invariant K(r,P) Type Equations Of State For Hydrodynamically Driven Flows, Submitted to the 12th American Physical Society Topical Group Meeting on Shock Compression of Condensed Matter (SCCM Shock 01), Atlanta, Georgia

  19. BDNF serum levels in schizophrenic patients during treatment augmentation with sarcosine (results of the PULSAR study).

    PubMed

    Strzelecki, Dominik; Kałużyńska, Olga; Wysokiński, Adam

    2016-08-30

    Finding a relationship between schizophrenia symptoms severity and initial level of BDNF and its changes during augmentation of antipsychotic treatment with sarcosine. 57 individuals with schizophrenia with predominantly negative symptoms completed a 6-month RCT prospective study. The patients received 2g of sarcosine (n=27) or placebo (n=30) daily. At the beginning, after 6 weeks and 6 months BDNF levels were measured. Severity of symptoms was assessed using the Positive and Negative Syndrome Scale (PANSS) and Calgary Depression Scale for Schizophrenia (CDSS). BDNF serum levels were stable after 6 weeks and 6 months in both groups. We noted improvement in negative symptoms, general psychopathology and total PANSS score in sarcosine group comparing to placebo, however there was no correlations between serum BDNF concentrations and PANSS scores in all assessments. Initial serum BDNF concentrations cannot be used as a predictor of the improvement resulting from adding sarcosine. Our results indicate that either BDNF is not involved in the NMDA-dependent mechanism of sarcosine action or global changes in BDNF concentrations induced by amino-acid cannot be detected in blood assessments. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  20. Adjunctive sarcosine plus benzoate improved cognitive function in chronic schizophrenia patients with constant clinical symptoms: A randomised, double-blind, placebo-controlled trial.

    PubMed

    Lin, Chun-Yuan; Liang, Sun-Yuan; Chang, Yue-Cune; Ting, Shuo-Yen; Kao, Ching-Ling; Wu, Yu-Hsin; Tsai, Guochuan E; Lane, Hsien-Yuan

    2017-08-01

    Objectives Hypofunction of NMDA receptor is implicated in the pathophysiology, particularly cognitive impairment, of schizophrenia. Sarcosine, a glycine transporter I (GlyT-1) inhibitor, and sodium benzoate, a d-amino acid oxidase (DAAO) inhibitor, can both enhance NMDA receptor-mediated neurotransmission. We proposed simultaneously inhibiting DAAO and GlyT-1 may be more effective than inhibition of either in improving the cognitive and global functioning of schizophrenia patients. Methods This study compared add-on sarcosine (2 g/day) plus benzoate (1 g/day) vs. sarcosine (2 g/day) for the clinical symptoms, as well as the cognitive and global functioning, of chronic schizophrenia patients in a 12-week, double-blind, randomised, placebo-controlled trial. Participants were measured with the Positive and Negative Syndrome Scale and the Global Assessment of Functioning Scale every 3 weeks. Seven cognitive domains, recommended by the Measurement and Treatment Research to Improve Cognition in Schizophrenia Committee, were measured at weeks 0 and 12. Results Adjunctive sarcosine plus benzoate, but not sarcosine alone, improved the cognitive and global functioning of patients with schizophrenia, even when their clinical symptoms had not improved. Conclusions This finding suggests N-methyl-d-aspartate receptor-enhancement therapy can improve the cognitive function of patients with schizophrenia, further indicating this pro-cognitive effect can be primary without improvement in clinical symptoms.

  1. Serum levels of interleukin 6 in schizophrenic patients during treatment augmentation with sarcosine (results of the PULSAR study).

    PubMed

    Strzelecki, Dominik; Urban-Kowalczyk, Małgorzata; Wysokiński, Adam

    2018-03-01

    Augmentation of sarcosine, a natural inhibitor of the glycine transporter type I, normalizes glutamatergic neurotransmission, having beneficial impact on primary negative symptoms in schizophrenia and may also influence immune system and interleukin 6 (IL-6) levels. Finding a relationship between initial IL-6 serum concentrations or its changes and severity of symptoms as a result of sarcosine addition to stable antipsychotic treatment. Fifity-eight individuals with schizophrenia with predominantly negative symptoms completed a 6-month randomized, double-blind placebo-controlled prospective study. Patients received 2 g of sarcosine (n = 29) or placebo (n = 30) daily per os. We measured IL-6 levels and severity of symptoms at the beginning, after 6 weeks and 6 months. As main clinical tools, we used Positive and Negative Syndrome Scale (PANSS) and Calgary depression scale for schizophrenia (CDSS). Augmentation with sarcosine had no effect on IL-6 serum levels in all time points. We noted significant improvements in negative symptoms, general psychopathology, and total PANSS score in the sarcosine group. We found correlation of initial serum IL-6 with severity of positive symptoms and negative association between IL-6 levels reduction and positive symptoms reduction. Sarcosine does not significantly affect IL-6 concentrations but IL-6 may be involved in mechanisms related to the presence of positive symptoms. Copyright © 2018 John Wiley & Sons, Ltd.

  2. Preparation, Characterization, and Antimicrobial Activities of Bimetallic Complexes of Sarcosine with Zn(II) and Sn(IV)

    PubMed Central

    Arafat, Yasir; Ali, Saqib; Shahzadi, Saira; Shahid, Muhammad

    2013-01-01

    Heterobimetallic complexes of Zn(II) and Sn(IV) with sarcosine have been synthesized at room temperature under stirring conditions by the reaction of sarcosine and zinc acetate in 2 : 1 molar ratio followed by the stepwise addition of CS2 and organotin(IV) halides, where R = Me, n-Bu, and Ph. The complexes were characterized by elemental analysis, FT-IR and NMR (1H, 13C) spectroscopy. IR data showed that the ligand acts in a bidentate manner. NMR data revealed the four coordinate geometry in solution state. In vitro antimicrobial activities data showed that complexes (3) and (4) were effective against bacterial and fungal strains with few exceptions. PMID:24235910

  3. Control of in vivo disposition and immunogenicity of polymeric micelles by adjusting poly(sarcosine) chain lengths on surface

    NASA Astrophysics Data System (ADS)

    Kurihara, Kensuke; Ueda, Motoki; Hara, Isao; Ozeki, Eiichi; Togashi, Kaori; Kimura, Shunsaku

    2017-07-01

    Four kinds of A3B-type amphiphilic polydepsipeptides, (poly(sarcosine))3- b-poly( l-lactic acid) (the degree of polymerization of poly(sarcosine) are 10, 33, 55, and 85; S10 3 , S33 3 , S55 3 , and S85 3 ) were synthesized to prepare core-shell type polymeric micelles. Their in vivo dispositions and stimulations to trigger immune system to produce IgM upon multiple administrations to mice were examined. With increasing poly(sarcosine) chain lengths, the hydrophilic shell became thicker and the surface density at the most outer surface decreased on the basis of dynamic and static light scattering measurements. These two physical elements of polymeric micelles elicited opposite effects on the immune response in light of the chain length therefore to show an optimized poly(sarcosine) chain length existing between 33mer and 55mer to suppress the accelerated blood clearance phenomenon associated with polymeric micelles.

  4. Crystal structure of heterotetrameric sarcosine oxidase from Corynebacterium sp. U-96

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ida, Koh; E-mail: idakoh@sci.kitasato-u.ac.jp; Moriguchi, Tomotaka

    2005-07-29

    Sarcosine oxidase from Corynebacterium sp. U-96 is a heterotetrameric enzyme. Here we report the crystal structures of the enzyme in complex with dimethylglycine and folinic acid. The {alpha} subunit is composed of two domains, contains NAD{sup +}, and binds folinic acid. The {beta} subunit contains dimethylglycine, FAD, and FMN, and these flavins are approximately 10 A apart. The {gamma} subunit is in contact with two domains of {alpha} subunit and has possibly a folate-binding structure. The {delta} subunit contains a single atom of zinc and has a Cys{sub 3}His zinc finger structure. Based on the structures determined and on themore » previous works, the structure-function relationship on the heterotetrameric sarcosine oxidase is discussed.« less

  5. Sarcosine and other metabolites along the choline oxidation pathway in relation to prostate cancer--a large nested case-control study within the JANUS cohort in Norway.

    PubMed

    de Vogel, Stefan; Ulvik, Arve; Meyer, Klaus; Ueland, Per Magne; Nygård, Ottar; Vollset, Stein Emil; Tell, Grethe S; Gregory, Jesse F; Tretli, Steinar; Bjørge, Tone

    2014-01-01

    Methyl group donors and intermediates of one-carbon metabolism affect DNA synthesis and DNA methylation, and may thereby affect prostate carcinogenesis. Choline, the precursor of betaine, and the one-carbon metabolite sarcosine have been associated with increased prostate cancer risk. Within JANUS, a prospective cohort in Norway (n = 317,000) with baseline serum samples, we conducted a nested case-control study among 3,000 prostate cancer cases and 3,000 controls. Using conditional logistic regression, odds ratios (ORs) and 95% confidence intervals (CIs) for prostate cancer risk were estimated according to quintiles of circulating betaine, dimethylglycine (DMG), sarcosine, glycine and serine. High sarcosine and glycine concentrations were associated with reduced prostate cancer risk of borderline significance (sarcosine: highest vs. lowest quintile OR = 0.86, CI = 0.72-1.01, p(trend) = 0.03; glycine: OR = 0.83, CI = 0.70-1.00, p(trend) = 0.07). Serum betaine, DMG and serine were not associated with prostate cancer risk. However, individuals with a high glycine/serine ratio were at decreased prostate cancer risk (OR = 0.74, CI = 0.69-0.85, p(trend) < 0.001). This population-based study suggested that men with high serum sarcosine or glycine concentrations have modestly reduced prostate cancer risk. Ratios of metabolites reflecting one-carbon balance may be associated with prostate cancer risk, as demonstrated for the glycine/serine ratio, and should be explored in future studies. © 2013 UICC.

  6. Identification of Sarcosine as a Target Molecule for the Canine Olfactory Detection of Prostate Carcinoma.

    PubMed

    Pacik, Dalibor; Plevova, Mariana; Urbanova, Lucie; Lackova, Zuzana; Strmiska, Vladislav; Necas, Alois; Heger, Zbynek; Adam, Vojtech

    2018-03-21

    The hypothesis that dogs can detect malignant tumours through the identification of specific molecules is nearly 30 years old. To date, several reports have described the successful detection of distinct types of cancer. However, is still a lack of data regarding the specific molecules that can be recognized by a dog's olfactory apparatus. Hence, we performed a study with artificially prepared, well-characterized urinary specimens that were enriched with sarcosine, a widely reported urinary biomarker for prostate cancer (PCa). For the purposes of the study, a German shepherd dog was utilized for analyses of 60 positive and 120 negative samples. Our study provides the first evidence that a sniffer dog specially trained for the olfactory detection of PCa can recognize sarcosine in artificial urine with a performance [sensitivity of 90%, specificity of 95%, and precision of 90% for the highest amount of sarcosine (10 µmol/L)] that is comparable to the identification of PCa-diagnosed subjects (sensitivity of 93.5% and specificity of 91.6%). This study casts light on the unrevealed phenomenon of PCa olfactory detection and opens the door for further studies with canine olfactory detection and cancer diagnostics.

  7. Resolution and Assignment of Differential Ion Mobility Spectra of Sarcosine and Isomers.

    PubMed

    Berthias, Francis; Maatoug, Belkis; Glish, Gary L; Moussa, Fathi; Maitre, Philippe

    2018-04-01

    Due to their central role in biochemical processes, fast separation and identification of amino acids (AA) is of importance in many areas of the biomedical field including the diagnosis and monitoring of inborn errors of metabolism and biomarker discovery. Due to the large number of AA together with their isomers and isobars, common methods of AA analysis are tedious and time-consuming because they include a chromatographic separation step requiring pre- or post-column derivatization. Here, we propose a rapid method of separation and identification of sarcosine, a biomarker candidate of prostate cancer, from isomers using differential ion mobility spectrometry (DIMS) interfaced with a tandem mass spectrometer (MS/MS) instrument. Baseline separation of protonated sarcosine from α- and β-alanine isomers can be easily achieved. Identification of DIMS peak is performed using an isomer-specific activation mode where DIMS- and mass-selected ions are irradiated at selected wavenumbers allowing for the specific fragmentation via an infrared multiple photon dissociation (IRMPD) process. Two orthogonal methods to MS/MS are thus added, where the MS/MS(IRMPD) is nothing but an isomer-specific multiple reaction monitoring (MRM) method. The identification relies on the comparison of DIMS-MS/MS(IRMPD) chromatograms recorded at different wavenumbers. Based on the comparison of IR spectra of the three isomers, it is shown that specific depletion of the two protonated α- and β-alanine can be achieved, thus allowing for clear identification of the sarcosine peak. It is also demonstrated that DIMS-MS/MS(IRMPD) spectra in the carboxylic C=O stretching region allow for the resolution of overlapping DIMS peaks. Graphical Abstract ᅟ.

  8. Resolution and Assignment of Differential Ion Mobility Spectra of Sarcosine and Isomers

    NASA Astrophysics Data System (ADS)

    Berthias, Francis; Maatoug, Belkis; Glish, Gary L.; Moussa, Fathi; Maitre, Philippe

    2018-02-01

    Due to their central role in biochemical processes, fast separation and identification of amino acids (AA) is of importance in many areas of the biomedical field including the diagnosis and monitoring of inborn errors of metabolism and biomarker discovery. Due to the large number of AA together with their isomers and isobars, common methods of AA analysis are tedious and time-consuming because they include a chromatographic separation step requiring pre- or post-column derivatization. Here, we propose a rapid method of separation and identification of sarcosine, a biomarker candidate of prostate cancer, from isomers using differential ion mobility spectrometry (DIMS) interfaced with a tandem mass spectrometer (MS/MS) instrument. Baseline separation of protonated sarcosine from α- and β-alanine isomers can be easily achieved. Identification of DIMS peak is performed using an isomer-specific activation mode where DIMS- and mass-selected ions are irradiated at selected wavenumbers allowing for the specific fragmentation via an infrared multiple photon dissociation (IRMPD) process. Two orthogonal methods to MS/MS are thus added, where the MS/MS(IRMPD) is nothing but an isomer-specific multiple reaction monitoring (MRM) method. The identification relies on the comparison of DIMS-MS/MS(IRMPD) chromatograms recorded at different wavenumbers. Based on the comparison of IR spectra of the three isomers, it is shown that specific depletion of the two protonated α- and β-alanine can be achieved, thus allowing for clear identification of the sarcosine peak. It is also demonstrated that DIMS-MS/MS(IRMPD) spectra in the carboxylic C=O stretching region allow for the resolution of overlapping DIMS peaks. [Figure not available: see fulltext.

  9. Molecular assessment of glyphosate-degradation pathway via sarcosine intermediate in Lysinibacillus sphaericus.

    PubMed

    González-Valenzuela, Laura E; Dussán, Jenny

    2018-05-31

    The widespread use of glyphosate has permeated not only small- and large-scale agriculture, but also the fight against drug trafficking and illicit crops. Health, alimentary security, and the rights of peasant and indigenous communities have been compromised in countries with intensive use of glyphosate-based herbicides. In 2015, the International Agency for Research on Cancer classified this substance as probably carcinogenic to humans, leading to the suspension of aerial glyphosate spraying the same year in countries like Colombia, where glyphosate has been extensively used in illicit crop eradication. Notwithstanding, according to a study of the U.S. Geological Survey, traces of glyphosate and its main degradation product, AMPA, remain in soil year after year. This underscores the urgency and importance of assessing new technologies to degrade glyphosate present in soils and waterbodies without leaving persistent byproducts. The aim of this study was to evaluate Lysinibacillus sphaericus' glyphosate uptake as a carbon and phosphorous source by a sarcosine-mediated metabolic pathway that releases glycine as final degradation product. To accomplish this, molecular and analytic evidence were collected in vitro from sarcosine oxidase activity, a key enzyme of a degradation pathway which releases byproducts that are easy to incorporate into natural biosynthesis routes.

  10. Improving the prediction of pathologic outcomes in patients undergoing radical prostatectomy: the value of prostate cancer antigen 3 (PCA3), prostate health index (phi) and sarcosine.

    PubMed

    Ferro, Matteo; Lucarelli, Giuseppe; Bruzzese, Dario; Perdonà, Sisto; Mazzarella, Claudia; Perruolo, Giuseppe; Marino, Ada; Cosimato, Vincenzo; Giorgio, Emilia; Tagliamonte, Virginia; Bottero, Danilo; De Cobelli, Ottavio; Terracciano, Daniela

    2015-02-01

    Several efforts have been made to find biomarkers that could help clinicians to preoperatively determine prostate cancer (PCa) pathological characteristics and choose the best therapeutic approach, avoiding over-treatment. On this effort, prostate cancer antigen 3 (PCA3), prostate health index (phi) and sarcosine have been presented as promising tools. We evaluated the ability of these biomarkers to predict the pathologic PCa characteristics within a prospectively collected contemporary cohort of patients who underwent radical prostatectomy (RP) for clinically localized PCa at a single high-volume Institution. The prognostic performance of PCA3, phi and sarcosine were evaluated in 78 patients undergoing RP for biopsy-proven PCa. Receiver operating characteristic (ROC) curve analyses tested the accuracy (area under the curve (AUC)) in predicting PCa pathological characteristics. Decision curve analyses (DCA) were used to assess the clinical benefit of the three biomarkers. We found that PCA3, phi and sarcosine levels were significantly higher in patients with tumor volume (TV)≥0.5 ml, pathologic Gleason sum (GS)≥7 and pT3 disease (all p-values≤0.01). ROC curve analysis showed that phi is an accurate predictor of high-stage (AUC 0.85 [0.77-0.93]), high-grade (AUC 0.83 [0.73-0.93]) and high-volume disease (AUC 0.94 [0.88-0.99]). Sarcosine showed a comparable AUC (0.85 [0.76-0.94]) only for T3 stage prediction, whereas PCA3 score showed lower AUCs, ranging from 0.74 (for GS) to 0.86 (for TV). PCA3, phi and sarcosine are predictors of PCa characteristics at final pathology. Successful clinical translation of these findings would reduce the frequency of surveillance biopsies and may enhance acceptance of active surveillance (AS). Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  11. Endogenous Abscisic Acid Promotes Hypocotyl Growth and Affects Endoreduplication during Dark-Induced Growth in Tomato (Solanum lycopersicum L.)

    PubMed Central

    Humplík, Jan F.; Bergougnoux, Véronique; Jandová, Michaela; Šimura, Jan; Pěnčík, Aleš; Tomanec, Ondřej; Rolčík, Jakub; Novák, Ondřej; Fellner, Martin

    2015-01-01

    Dark-induced growth (skotomorphogenesis) is primarily characterized by rapid elongation of the hypocotyl. We have studied the role of abscisic acid (ABA) during the development of young tomato (Solanum lycopersicum L.) seedlings. We observed that ABA deficiency caused a reduction in hypocotyl growth at the level of cell elongation and that the growth in ABA-deficient plants could be improved by treatment with exogenous ABA, through which the plants show a concentration dependent response. In addition, ABA accumulated in dark-grown tomato seedlings that grew rapidly, whereas seedlings grown under blue light exhibited low growth rates and accumulated less ABA. We demonstrated that ABA promotes DNA endoreduplication by enhancing the expression of the genes encoding inhibitors of cyclin-dependent kinases SlKRP1 and SlKRP3 and by reducing cytokinin levels. These data were supported by the expression analysis of the genes which encode enzymes involved in ABA and CK metabolism. Our results show that ABA is essential for the process of hypocotyl elongation and that appropriate control of the endogenous level of ABA is required in order to drive the growth of etiolated seedlings. PMID:25695830

  12. Salicylic acid antagonizes abscisic acid inhibition of shoot growth and cell cycle progression in rice

    NASA Astrophysics Data System (ADS)

    Meguro, Ayano; Sato, Yutaka

    2014-04-01

    We analysed effects of abscisic acid (ABA, a negative regulatory hormone), alone and in combination with positive or neutral hormones, including salicylic acid (SA), on rice growth and expression of cell cycle-related genes. ABA significantly inhibited shoot growth and induced expression of OsKRP4, OsKRP5, and OsKRP6. A yeast two-hybrid assay showed that OsKRP4, OsKRP5, and OsKRP6 interacted with OsCDKA;1 and/or OsCDKA;2. When SA was simultaneously supplied with ABA, the antagonistic effect of SA completely blocked ABA inhibition. SA also blocked ABA inhibition of DNA replication and thymidine incorporation in the shoot apical meristem. These results suggest that ABA arrests cell cycle progression by inducing expression of OsKRP4, OsKRP5, and OsKRP6, which inhibit the G1/S transition, and that SA antagonizes ABA by blocking expression of OsKRP genes.

  13. Halogenides of dimethylglycine in comparison with respective salts of glycine, sarcosine and betaine

    NASA Astrophysics Data System (ADS)

    Petrosyan, A. M.; Ghazaryan, V. V.; Giester, G.; Fleck, M.; Tylczyński, Z.; Wiesner, M.

    2018-04-01

    We investigated salts formation in the DMG(dimethylglycine)sbnd HClsbnd H2O, DMGsbnd HBrsbnd H2O and DMGsbnd HIsbnd H2O systems. In addition to previously known dimethylglycinium chloride (DMGH)Cl, we obtained and characterized (structurally and spectroscopically) the following crystals: (DMGH)Br, (DMGH)I as well as the first salts of DMG with dimeric (DMG⋯DMGH) cation: (DMG⋯DMGH)Cl, (DMG⋯DMGH)Br, (DMG⋯DMGH)I. Obtained results are compared with results of known or newly obtained respective salts of glycine, sarcosine (monomethylglycine) and betaine (trimethylglycine).

  14. Enzyme cytochemical localization of sarcosine oxidase activity in the liver and kidney of several mammals.

    PubMed

    Chikayama, M; Ohsumi, M; Yokota, S

    2000-06-01

    We investigated the enzyme cytochemical localization of sarcosine oxidase (SOX) in the liver and kidney of several mammals using a cerium technique. First we measured the enzyme activities in the liver and kidney of several mammals and in several organs of mice. The highest activity was found in the Chinese hamster, followed by the mouse. Therefore, we used hamster and mouse tissues for enzyme cytochemistry. The liver and kidneys were fixed by perfusion with various concentrations of glutaraldehyde for 10 min. Tissue slices were incubated in reaction medium consisting of 50 mM TRIS-maleate buffer (pH 7.8), 9 mM sodium azide, 9.8 mM sarcosine, 25 microM FAD, 2 mM cerium chloride, 0.002% saponin, and 0.003% Triton X-100 for 0.5-8 h at 37 degrees C. Optimum staining reaction was obtained in tissues fixed with 0.2% glutaraldehyde, followed by incubation for 2-4 h. Electron-dense reaction products were present exclusively in peroxisomes. Within the peroxisomes strong reactions were observed in the matrix subjacent to the limiting membrane decreasing toward the center. The staining reaction was completely inhibited by 2 mM N-bromosuccinimide. These results indicated that SOX is a peroxisomal enzyme and that the enzyme might be associated with the peroxisomal membrane.

  15. Arabidopsis JAGGED links floral organ patterning to tissue growth by repressing Kip-related cell cycle inhibitors.

    PubMed

    Schiessl, Katharina; Muiño, Jose M; Sablowski, Robert

    2014-02-18

    Plant morphogenesis requires coordinated cytoplasmic growth, oriented cell wall extension, and cell cycle progression, but it is debated which of these processes are primary drivers for tissue growth and directly targeted by developmental genes. Here, we used ChIP high-throughput sequencing combined with transcriptome analysis to identify global target genes of the Arabidopsis transcription factor JAGGED (JAG), which promotes growth of the distal region of floral organs. Consistent with the roles of JAG during organ initiation and subsequent distal organ growth, we found that JAG directly repressed genes involved in meristem development, such as CLAVATA1 and HANABA TARANU, and genes involved in the development of the basal region of shoot organs, such as BLADE ON PETIOLE 2 and the GROWTH REGULATORY FACTOR pathway. At the same time, JAG regulated genes involved in tissue polarity, cell wall modification, and cell cycle progression. In particular, JAG directly repressed KIP RELATED PROTEIN 4 (KRP4) and KRP2, which control the transition to the DNA synthesis phase (S-phase) of the cell cycle. The krp2 and krp4 mutations suppressed jag defects in organ growth and in the morphology of petal epidermal cells, showing that the interaction between JAG and KRP genes is functionally relevant. Our work reveals that JAG is a direct mediator between genetic pathways involved in organ patterning and cellular functions required for tissue growth, and it shows that a regulatory gene shapes plant organs by releasing a constraint on S-phase entry.

  16. Promotion of chloroplast proliferation upon enhanced post-mitotic cell expansion in leaves.

    PubMed

    Kawade, Kensuke; Horiguchi, Gorou; Ishikawa, Naoko; Hirai, Masami Yokota; Tsukaya, Hirokazu

    2013-09-28

    Leaves are determinate organs; hence, precise control of cell proliferation and post-mitotic cell expansion is essential for their growth. A defect in cell proliferation often triggers enhanced post-mitotic cell expansion in leaves. This phenomenon is referred to as 'compensation'. Several lines of evidence from studies on compensation have shown that cell proliferation and post-mitotic cell expansion are coordinately regulated during leaf development. Therefore, compensation has attracted much attention to the mechanisms for leaf growth. However, our understanding of compensation at the subcellular level remains limited because studies of compensation have focused mainly on cellular-level phenotypes. Proper leaf growth requires quantitative control of subcellular components in association with cellular-level changes. To gain insight into the subcellular aspect of compensation, we investigated the well-known relationship between cell area and chloroplast number per cell in compensation-exhibiting lines, and asked whether chloroplast proliferation is modulated in response to the induction of compensation. We first established a convenient and reliable method for observation of chloroplasts in situ. Using this method, we analyzed Arabidopsis thaliana mutants fugu5 and angustifolia3 (an3), and a transgenic line KIP-RELATED PROTEIN2 overexpressor (KRP2 OE), which are known to exhibit typical features of compensation. We here showed that chloroplast number per cell increased in the subepidermal palisade tissue of these lines. We analyzed tetraploidized wild type, fugu5, an3 and KRP2 OE, and found that cell area itself, but not nuclear ploidy, is a key parameter that determines the activity of chloroplast proliferation. In particular, in the case of an3, we uncovered that promotion of chloroplast proliferation depends on the enhanced post-mitotic cell expansion. The expression levels of chloroplast proliferation-related genes are similar to or lower than that in the wild

  17. Promotion of chloroplast proliferation upon enhanced post-mitotic cell expansion in leaves

    PubMed Central

    2013-01-01

    Background Leaves are determinate organs; hence, precise control of cell proliferation and post-mitotic cell expansion is essential for their growth. A defect in cell proliferation often triggers enhanced post-mitotic cell expansion in leaves. This phenomenon is referred to as ‘compensation’. Several lines of evidence from studies on compensation have shown that cell proliferation and post-mitotic cell expansion are coordinately regulated during leaf development. Therefore, compensation has attracted much attention to the mechanisms for leaf growth. However, our understanding of compensation at the subcellular level remains limited because studies of compensation have focused mainly on cellular-level phenotypes. Proper leaf growth requires quantitative control of subcellular components in association with cellular-level changes. To gain insight into the subcellular aspect of compensation, we investigated the well-known relationship between cell area and chloroplast number per cell in compensation-exhibiting lines, and asked whether chloroplast proliferation is modulated in response to the induction of compensation. Results We first established a convenient and reliable method for observation of chloroplasts in situ. Using this method, we analyzed Arabidopsis thaliana mutants fugu5 and angustifolia3 (an3), and a transgenic line KIP-RELATED PROTEIN2 overexpressor (KRP2 OE), which are known to exhibit typical features of compensation. We here showed that chloroplast number per cell increased in the subepidermal palisade tissue of these lines. We analyzed tetraploidized wild type, fugu5, an3 and KRP2 OE, and found that cell area itself, but not nuclear ploidy, is a key parameter that determines the activity of chloroplast proliferation. In particular, in the case of an3, we uncovered that promotion of chloroplast proliferation depends on the enhanced post-mitotic cell expansion. The expression levels of chloroplast proliferation-related genes are similar to or

  18. Distribution of Non-AT1, Non-AT2 Binding of 125I-Sarcosine1, Isoleucine8 Angiotensin II in Neurolysin Knockout Mouse Brains

    PubMed Central

    Speth, Robert C.; Carrera, Eduardo J.; Bretón, Catalina; Linares, Andrea; Gonzalez-Reiley, Luz; Swindle, Jamala D.; Santos, Kira L.; Schadock, Ines; Bader, Michael; Karamyan, Vardan T.

    2014-01-01

    The recent identification of a novel binding site for angiotensin (Ang) II as the peptidase neurolysin (E.C. 3.4.24.16) has implications for the renin-angiotensin system (RAS). This report describes the distribution of specific binding of 125I-Sarcosine1, Isoleucine8 Ang II (125I-SI Ang II) in neurolysin knockout mouse brains compared to wild-type mouse brains using quantitative receptor autoradiography. In the presence of p-chloromercuribenzoic acid (PCMB), which unmasks the novel binding site, widespread distribution of specific (3 µM Ang II displaceable) 125I-SI Ang II binding in 32 mouse brain regions was observed. Highest levels of binding >700 fmol/g initial wet weight were seen in hypothalamic, thalamic and septal regions, while the lowest level of binding <300 fmol/g initial wet weight was in the mediolateral medulla. 125I-SI Ang II binding was substantially higher by an average of 85% in wild-type mouse brains compared to neurolysin knockout brains, suggesting the presence of an additional non-AT1, non-AT2, non-neurolysin Ang II binding site in the mouse brain. Binding of 125I-SI Ang II to neurolysin in the presence of PCMB was highest in hypothalamic and ventral cortical brain regions, but broadly distributed across all regions surveyed. Non-AT1, non-AT2, non-neurolysin binding was also highest in the hypothalamus but had a different distribution than neurolysin. There was a significant reduction in AT2 receptor binding in the neurolysin knockout brain and a trend towards decreased AT1 receptor binding. In the neurolysin knockout brains, the size of the lateral ventricles was increased by 56% and the size of the mid forebrain (−2.72 to +1.48 relative to Bregma) was increased by 12%. These results confirm the identity of neurolysin as a novel Ang II binding site, suggesting that neurolysin may play a significant role in opposing the pathophysiological actions of the brain RAS and influencing brain morphology. PMID:25147932

  19. An improved amperometric creatinine biosensor based on nanoparticles of creatininase, creatinase and sarcosine oxidase.

    PubMed

    Kumar, Parveen; Jaiwal, Ranjana; Pundir, C S

    2017-11-15

    An improved amperometric biosensor for detection of creatinine was developed based on immobilization of nanoparticles (NPs) of creatininase (CA), creatinase (CI), and sarcosine oxidase (SOx) onto glassy carbon (GC) electrode. Transmission electron microscopy (TEM) and fourier transform infrared spectroscopy (FTIR) were employed for characterization of enzyme nanoparticles (ENPs). The GC electrode was characterized by scanning electron microscopy (SEM), cyclic voltammetry (CV) and electrochemical impedance spectra (EIS) at different stages of its amendment. The biosensor showed optimum response within 2s at pH 6.0 in 0.1 M sodium phosphate buffer and 25 °C, when operated at 1.0 V against Ag/AgCl. Biosensor exhibited wider linear range from 0.01 μM to 12 μM with a limit of detection (LOD) of 0.01 μM. The analytical recoveries of added creatinine in sera were 97.97 ± 0.1% for 0.1 mM and 98.76 ± 0.2% for 0.15 mM, within and between batch coefficients of variation (CV) were 2.06% and 3.09% respectively. A good correlation (R 2  = 0.99) was observed between sera creatinine values obtained by standard enzymic colorimetric method and the present biosensor. This biosensor measured creatinine level in sera of apparently healthy subjects and persons suffering from renal and muscular dysfunction. The ENPs electrode lost 10% of its initial activity within 240 days of its regular uses, when stored at 4 °C. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Cadmium toxicity induced contrasting patterns of concentrations of free sarcosine, specific amino acids and selected microelements in two Noccaea species

    PubMed Central

    Zemanová, Veronika; Pavlík, Milan; Pavlíková, Daniela

    2017-01-01

    Cadmium (Cd) toxicity affects numerous metabolic processes in plants. In the presence of Cd, plants accumulate specific amino acids which may be beneficial to developing Cd tolerance. Our study aimed to characterize the changes in the metabolism of selected free amino acids that are associated with Cd tolerance, and investigate the levels of selected microelements in order to relate these changes to the adaptation strategies of two metallophytes—Noccaea caerulescens (Redlschlag, Austria) and Noccaea praecox (Mežica, Slovenia). The plants were exposed to Cd contamination (90 mg Cd/kg soil) for 120 days in a pot experiment. Our results showed higher Cd accumulation in N. praecox compared to N. caerulescens. Cadmium contamination reduced the zinc and nickel levels in both species and a mixed effect was determined for copper and manganese content. Differences in free amino acid metabolism were observed between the two metallophytes growing under Cd-free and Cd-loaded conditions. Under Cd-free conditions, aromatic amino acids (phenylalanine, tryptophan and tyrosine) and branched-chain amino acids (leucine, isoleucine and valine) were accumulated more in the leaves of N. praecox than in N. caerulescens. Cd stress increased the content of these amino acids in both species but this increase was significant only in N. caerulescens leaves. Marked differences in the responses of the two species to Cd stress were shown for alanine, phenylalanine, threonine and sarcosine. Cadmium contamination also induced an increase of threonine as alanine and sarcosine decrease, which was larger in N. caerulescens than in N. praecox. All these factors contribute to the higher adaptation of N. praecox to Cd stress. PMID:28542385

  1. Cadmium toxicity induced contrasting patterns of concentrations of free sarcosine, specific amino acids and selected microelements in two Noccaea species.

    PubMed

    Zemanová, Veronika; Pavlík, Milan; Pavlíková, Daniela

    2017-01-01

    Cadmium (Cd) toxicity affects numerous metabolic processes in plants. In the presence of Cd, plants accumulate specific amino acids which may be beneficial to developing Cd tolerance. Our study aimed to characterize the changes in the metabolism of selected free amino acids that are associated with Cd tolerance, and investigate the levels of selected microelements in order to relate these changes to the adaptation strategies of two metallophytes-Noccaea caerulescens (Redlschlag, Austria) and Noccaea praecox (Mežica, Slovenia). The plants were exposed to Cd contamination (90 mg Cd/kg soil) for 120 days in a pot experiment. Our results showed higher Cd accumulation in N. praecox compared to N. caerulescens. Cadmium contamination reduced the zinc and nickel levels in both species and a mixed effect was determined for copper and manganese content. Differences in free amino acid metabolism were observed between the two metallophytes growing under Cd-free and Cd-loaded conditions. Under Cd-free conditions, aromatic amino acids (phenylalanine, tryptophan and tyrosine) and branched-chain amino acids (leucine, isoleucine and valine) were accumulated more in the leaves of N. praecox than in N. caerulescens. Cd stress increased the content of these amino acids in both species but this increase was significant only in N. caerulescens leaves. Marked differences in the responses of the two species to Cd stress were shown for alanine, phenylalanine, threonine and sarcosine. Cadmium contamination also induced an increase of threonine as alanine and sarcosine decrease, which was larger in N. caerulescens than in N. praecox. All these factors contribute to the higher adaptation of N. praecox to Cd stress.

  2. Strong Negative Interference by Calcium Dobesilate in Sarcosine Oxidase Assays for Serum Creatinine Involving the Trinder Reaction

    PubMed Central

    Guo, Xiuzhi; Hou, Li’an; Cheng, Xinqi; Zhang, Tianjiao; Yu, Songlin; Fang, Huiling; Xia, Liangyu; Qi, Zhihong; Qin, Xuzhen; Zhang, Lin; Liu, Qian; Liu, Li; Chi, Shuling; Hao, Yingying; Qiu, Ling

    2015-01-01

    Abstract The vasoprotective drug calcium dobesilate is known to interfere with creatinine (Cr) quantifications in sarcosine oxidase enzymatic (SOE) assays. The aim of this study was to investigate this interference in 8 different commercially available assays and to determine its clinical significance. In in vitro experiments, interference was evaluated at 3 Cr levels. For this, Cr was quantified by SOE assays in pooled serum supplemented with calcium dobesilate at final concentrations of 0, 2, 4, 8, 16, 32, and 64 μg/mL. Percent bias was calculated relative to the drug-free specimen. For in vivo analyses, changes in serum concentrations of Cr, cystatin C (CysC; a renal function marker), and calcium dobesilate were monitored in healthy participants of group I before and after oral calcium dobesilate administration. In addition, variations in interference were also examined among different SOE assays using serum obtained from healthy participants of group II. Lastly, Cr levels from the 10 patients treated with calcium dobesilate were measured using 4 SOE assays and liquid chromatography-isotope dilution tandem mass spectrometry (LC-IDMS/MS) for comparison. Our in vitro analyses indicated that the presence of 8 μg/mL calcium dobesilate resulted in a −4.4% to −36.3% reduction in Cr serum concentration compared to drug-free serum for 8 SOE assays examined. In vivo, Cr values decreased relative to the baseline level with increasing drug concentration, with the lowest Cr levels obtained at 2 or 3 hours after drug administration in participants of group I. The observed Cr concentrations for participants in group II were reduced by −28.5% to −3.1% and −60.5% to −11.6% at 0 and 2 hours after administration related to baseline levels. The Cr values of 10 patients measured by Roche, Beckman, Maker, and Merit Choice SOE assays showed an average deviation of −20.0%, −22.4%, −14.2%, and −29.6%, respectively, compared to values obtained by LC

  3. Anti-oxidant effect of extracts of kinnow rind, pomegranate rind and seed powders in cooked goat meat patties.

    PubMed

    Devatkal, Suresh K; Narsaiah, K; Borah, A

    2010-05-01

    To overcome the disadvantages of using synthetic anti-oxidants in meat products, an investigation was carried out to evaluate the anti-oxidant effect of extracts of fruit by-products viz., kinnow rind powder (KRP), pomegranate rind powder (PRP) and pomegranate seed powder (PSP) in goat meat patties. Total phenolics content, DPPH radical scavenging activity and effect of these extracts on instrumental color, sensory attributes and TBARS values during storage (4+/-1 degrees C) of goat meat patties were evaluated. Results showed that these extracts are rich sources of phenolic compounds having free radical scavenging activity. Hunter Lab L value significantly (P<0.05) lowered in PRP followed by PSP and KRP patties. Sensory evaluation indicated no significant differences among patties. Further, a significant (P<0.5) reduction in TBARS values (lipid oxidation) during storage of goat meat patties was observed in PRP, PSP and KRP as compared to control patties. Average TBARS values (mg/kg meat) during refrigerated storage (4+/-1 degrees C) were significantly lower in PRP, followed by PSP and KRP as compared to control. The overall anti-oxidant effect was in the order of PRP>PSP>KRP. It was concluded that extracts of above fruits by-product powders have potential to be used as natural anti-oxidants in meat products. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  4. Effect of salt, kinnow and pomegranate fruit by-product powders on color and oxidative stability of raw ground goat meat during refrigerated storage.

    PubMed

    Devatkal, Suresh K; Naveena, B M

    2010-06-01

    Effects of salt, kinnow and pomegranate fruit by-product powders on color and oxidative stability of raw ground goat meat stored at 4+/-1 degrees C was evaluated. Five treatments evaluated include: control (only meat), MS (meat+2% salt), KRP (meat+2% salt+2% kinnow rind powder), PRP (meat+2% salt+2% pomegranate rind powder) and PSP (meat+2% salt+2% pomegranate seed powder). Addition of salt resulted in reduction of redness scores. Lightness increased in control and unchanged in others during storage. Redness scores declined and yellowness showed inconsistent changes during storage. Thiobarbituric acid reactive substances (TBARS) values were higher (P<0.05) in MS followed by control and KRP samples compared to PRP and PSP samples throughout storage. The PSP treated samples showed lowest TBARS values than others. Percent reduction of TBARS values was highest in PSP (443%) followed by PRP (227%) and KRP (123%). Salt accelerated the TBARS formation and by-products of kinnow and pomegranate fruits counteracted this effect. The overall antioxidant effect was in the order of PSP>PRP>KRP>control>MS. Therefore, these powders have potential to be used as natural antioxidants to minimize the auto-oxidation and salt induced lipid oxidation in raw ground goat meat. Crown Copyright 2010. Published by Elsevier Ltd. All rights reserved.

  5. Targeted manipulation of leaf form via local growth repression.

    PubMed

    Malinowski, Robert; Kasprzewska, Ania; Fleming, Andrew J

    2011-06-01

    A classical view is that leaf shape is the result of local promotion of growth linked to cell proliferation. However, an alternative hypothesis is that leaf form is the result of local repression of growth in an otherwise growing system. Here we show that leaf form can indeed be manipulated in a directed fashion by local repression of growth. We show that targeting expression of an inhibitor of a cyclin-dependent kinase (KRP1) to the sinus area of developing leaves of Arabidopsis leads to local growth repression and the formation of organs with extreme lobing, including generation of leaflet-like organs. Directing KRP1 expression to other regions of the leaf using an miRNA target sequence tagging approach also leads to predictable novel leaf forms, and repression of growth in the leaf margin blocks the outgrowth of lobes, leading to a smoother perimeter. In addition, we show that decreased growth around the perimeter and across the leaf abaxial surface leads to a change in 3D form, as predicted by mechanical models of leaf growth. Our analysis provides experimental evidence that local repression of growth influences leaf shape, suggesting that it could be part of the mechanism of morphogenesis in plants in the context of an otherwise growing system. © 2011 The Authors. The Plant Journal © 2011 Blackwell Publishing Ltd.

  6. Degradation of Glyphosate by Mn-Oxide May Bypass Sarcosine and Form Glycine Directly after C-N Bond Cleavage.

    PubMed

    Li, Hui; Wallace, Adam F; Sun, Mingjing; Reardon, Patrick; Jaisi, Deb P

    2018-02-06

    Glyphosate is the active ingredient of the common herbicide Roundup. The increasing presence of glyphosate and its byproducts has raised concerns about its potential impact on the environment and human health. In this research, we investigated abiotic pathways of glyphosate degradation as catalyzed by birnessite under aerobic and neutral pH conditions to determine whether certain pathways have the potential to generate less harmful intermediate products. Nuclear magnetic resonance (NMR) spectroscopy and high-performance liquid chromatography (HPLC) were utilized to identify and quantify reaction products, and density functional theory (DFT) calculations were used to investigate the bond critical point (BCP) properties of the C-N bond in glyphosate and Mn(IV)-complexed glyphosate. We found that sarcosine, the commonly recognized precursor to glycine, was not present at detectable levels in any of our experiments despite the fact that its half-life (∼13.6 h) was greater than our sampling intervals. Abiotic degradation of glyphosate largely followed the glycine pathway rather than the AMPA (aminomethylphosphonic acid) pathway. Preferential cleavage of the phosphonate adjacent C-N bond to form glycine directly was also supported by our BCP analysis, which revealed that this C-N bond was disproportionately affected by the interaction of glyphosate with Mn(IV). Overall, these results provide useful insights into the potential pathways through which glyphosate may degrade via relatively benign intermediates.

  7. A Predicted Mannoprotein Participates in Cryptococcus gattii Capsular Structure

    PubMed Central

    Reuwsaat, Julia Catarina Vieira; Motta, Heryk; Garcia, Ane Wichine Acosta; Vasconcelos, Carolina Bettker; Marques, Bárbara Machado; Oliveira, Natália Kronbauer; Rodrigues, Jéssica; Ferrareze, Patrícia Aline Gröhns; Frases, Susana; Barcellos, Vanessa Abreu; Squizani, Eamim Daidrê; Horta, Jorge André; Schrank, Augusto; Staats, Charley Christian; Vainstein, Marilene Henning

    2018-01-01

    ABSTRACT The yeast-like pathogen Cryptococcus gattii is an etiological agent of cryptococcosis. The major cryptococcal virulence factor is the polysaccharide capsule, which is composed of glucuronoxylomannan (GXM), galactoxylomannan (GalXM), and mannoproteins (MPs). The GXM and GalXM polysaccharides have been extensively characterized; however, there is little information about the role of mannoproteins in capsule assembly and their participation in yeast pathogenicity. The present study characterized the function of a predicted mannoprotein from C. gattii, designated Krp1. Loss-of-function and gain-of-function mutants were generated, and phenotypes associated with the capsular architecture were evaluated. The null mutant cells were more sensitive to a cell wall stressor that disrupts beta-glucan synthesis. Also, these cells displayed increased GXM release to the culture supernatant than the wild-type strain did. The loss of Krp1 influenced cell-associated cryptococcal polysaccharide thickness and phagocytosis by J774.A1 macrophages in the early hours of interaction, but no difference in virulence in a murine model of cryptococcosis was observed. In addition, recombinant Krp1 was antigenic and differentially recognized by serum from an individual with cryptococcosis, but not with serum from an individual with candidiasis. Taken together, these results indicate that C. gattii Krp1 is important for the cell wall structure, thereby influencing capsule assembly, but is not essential for virulence in vivo. IMPORTANCE Cryptococcus gattii has the ability to escape from the host’s immune system through poorly understood mechanisms and can lead to the death of healthy individuals. The role of mannoproteins in C. gattii pathogenicity is not completely understood. The present work characterized a protein, Kpr1, that is essential for the maintenance of C. gattii main virulence factor, the polysaccharide capsule. Our data contribute to the understanding of the role of Kpr

  8. Pretreatment with propidium monoazide/sodium lauroyl sarcosinate improves discrimination of infectious waterborne virus by RT-qPCR combined with magnetic separation.

    PubMed

    Lee, Hae-Won; Lee, Hee-Min; Yoon, So-Ra; Kim, Sung Hyun; Ha, Ji-Hyoung

    2018-02-01

    RT-qPCR allows sensitive detection of viral particles of both infectious and noninfectious viruses in water environments, but cannot discriminate non-infectious from infectious viruses. In this study, we aimed to optimize RT-qPCR-based detection of chlorine-inactivated human norovirus (NoV) and pepper mild mottle virus (PMMoV) in suspension by pretreatment with an optimal combination of a monoazide and a detergent that can efficiently penetrate damaged viral capsids. Four methods were compared to determine the efficacy of chlorine disinfection (at 1, 3, and 5 min mg/L): (A) RT-qPCR alone, (B) RT-qPCR assay preceded by magnetic bead separation for enrichment of viral particles (MBS-RT-qPCR), (C) MBS-RT-qPCR assay with pretreatment with propidium monoazide (PMA-MBS-RT-qPCR), and (D) PMA-MBS-RT-qPCR assay with pretreatment with sodium lauroyl sarcosinate (INCI-PMA-MBS-RT-qPCR). On the basis of a PMA optimization assay, 200 and 300 μM PMA were used in subsequent experiments for NoV GII.4 and PMMoV, respectively. Optimal INCI concentrations, having minimal influence on NoV GII.4 and PMMoV, were found to be 0.5% and 0.2% INCI, respectively. For NoV GII.4, there were significant differences (P < 0.05) in log 10 genome copies between the PMA-treated and the INCI + PMA-treated samples (log 10 genome copies differed by 1.11 and 0.59 log 10 for 3 and 5 min mg/L of chlorine, respectively). For PMMoV, INCI induced differences in log 10 genome copies of 0.92, 1.18, and 1.86, for 1, 3, and 5 min mg/L of chlorine, respectively. Overall, the results of this study indicate that an optimal combination of PMA and INCI could be very useful for evaluating disinfection methods in water treatment strategies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. 4 CFR 3.1 - Appointment, promotion, and assignment.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 4 Accounts 1 2010-01-01 2010-01-01 false Appointment, promotion, and assignment. 3.1 Section 3.1 Accounts GOVERNMENT ACCOUNTABILITY OFFICE PERSONNEL SYSTEM EMPLOYMENT § 3.1 Appointment, promotion, and assignment. Employees of GAO shall be appointed, promoted and assigned solely on the basis of merit and...

  10. Coherent Experimental and Simulation Approach To Explore the Underlying Mechanism of Denaturation of Stem Bromelain in Osmolytes.

    PubMed

    Rani, Anjeeta; Taha, Mohamed; Venkatesu, Pannuru; Lee, Ming-Jer

    2017-07-13

    Characterization of a protein in the context of its environment is of crucial importance for a complete understanding of its function. Although biophysical techniques provide powerful tools for studying the stability and activity of the enzyme in the presence of various cosolvents, an approach of combining both experimental techniques and molecular dynamic (MD) simulations may lead to the mechanistic insight into the interactions governing the stability of an enzyme. The knowledge of these interactions can be further utilized for range of modifications in the wild form of an enzyme for various pharmaceutical applications. Herein, we employed florescence, UV-visible, circular dichroism (CD), dynamic light scattering (DLS) study, and MD simulations for comprehensive understanding of stem bromelain (BM) in the presence of betaine, sarcosine, arginine, and proline. The thermal stability of BM in the presence of 1 M of osmolytes is found to be in order: proline > betaine > buffer > arginine > sarcosine. BM gets more preferentially hydrated in the presence of betaine and proline than in sarcosine and arginine. Nonetheless, MD simulations suggest that betaine, sarcosine, and arginine at 1 M interact with the active site of BM through H-bonding except proline which are responsible for more disruption of active site. The distances between the catalytic site residues are 1.6, 1.9, 4.3, 5.0, and 6.2 Å for BM in proline, buffer, betaine, arginine, and sarcosine at 1 M, respectively. To the best of our knowledge, this is the first report on detailed unequivocal evidence of denaturation and deactivation of BM in the presence of methylamines and amino acids.

  11. 37 CFR 4.1 - Complaints regarding invention promoters.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Complaints regarding invention promoters. 4.1 Section 4.1 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE, DEPARTMENT OF COMMERCE GENERAL COMPLAINTS REGARDING INVENTION PROMOTERS § 4.1 Complaints...

  12. Stimulus-Dependent, Promoter-Specific Binding of Transcription Factor WRKY1 to Its Native Promoter and the Defense-Related Gene PcPR1-1 in ParsleyW⃞

    PubMed Central

    Turck, Franziska; Zhou, Aifen; Somssich, Imre E.

    2004-01-01

    WRKY transcription factors form a large family that plays a role in plant responses to biotic stress and during senescence. Defining in vivo relevant WRKY/promoter relationships has been hampered by the factors' indiscriminate binding to known W box DNA elements and their possible genetic redundance. Employing chromatin immunoprecipitations (ChIP) of cultured cells, we show that parsley (Petroselinum crispum) WRKY1 protein binds to the W boxes of its native promoter as well as to that of PcWRKY3 and the defense-related PR10-class marker gene Pathogenesis-Related1-1 (PcPR1-1). Although present at low concentrations in resting cells, WRKY1 does not appear to play a role in the immediate early gene response upon elicitation because it does not bind to the promoter at this time. Paradoxically, in vivo binding at the PcWRKY1 promoter correlates more with downregulation of gene expression, whereas previous overexpression studies suggested an activating function of WRKY1 on PcWRKY1 expression. By contrast, PcPR1-1 expression remains strong when its promoter is occupied in vivo by WRKY1. Unexpectedly, ChIP revealed that W boxes at promoter sites are constitutively occupied by other WRKY transcription factors, indicating that site recruitment does not seem to play a major role in their regulation. Rather, WRKY proteins very likely act in a network of mutually competing participants with temporal displacement occurring at defined preoccupied sites by other family members in a stimulus-dependent manner. PMID:15367720

  13. Influence of Long-Distance Bicycle Riding on Serum/Urinary Biomarkers of Prostate Cancer

    PubMed Central

    Heger, Zbynek; Gumulec, Jaromir; Ondrak, Ales; Skoda, Jan; Zitka, Zdenek; Cernei, Natalia; Masarik, Michal; Zitka, Ondrej; Adam, Vojtech

    2016-01-01

    Herein, we present a study focused on the determination of the influence of long-distance (53 km) bicycle riding on levels of chosen biochemical urinary and serum prostate cancer (PCa) biomarkers total prostate-specific antigen (tPSA), free PSA (fPSA) and sarcosine. Fourteen healthy participants with no evidence of prostate diseases, in the age range from 49–57 years with a median of 52 years, underwent physical exercise (mean race time of 150 ± 20 min, elevation increase of 472 m) and pre- and post-ride blood/urine sampling. It was found that bicycle riding resulted in elevated serum uric acid (p = 0.001, median 271.76 vs. 308.44 µmol/L pre- and post-ride, respectively), lactate (p = 0.01, median 2.98 vs. 4.8 mmol/L) and C-reactive protein (p = 0.01, 0.0–0.01 mg/L). It is noteworthy that our work supports the studies demonstrating an increased PSA after mechanical manipulation of the prostate. The subjects exhibited either significantly higher post-ride tPSA (p = 0.002, median 0.69 vs. 1.1 ng/mL pre- and post-ride, respectively) and fPSA (p = 0.028, median 0.25 vs. 0.35 ng/mL). Contrary to that, sarcosine levels were not significantly affected by physical exercise (p = 0.20, median 1.64 vs. 1.92 µmol/mL for serum sarcosine, and p = 0.15, median 0.02 µmol/mmol of creatinine vs. 0.01 µmol/mmol of creatinine for urinary sarcosine). Taken together, our pilot study provides the first evidence that the potential biomarker of PCa—sarcosine does not have a drawback by means of a bicycle riding-induced false positivity, as was shown in the case of PSA. PMID:26999116

  14. Functional characterization of the human phosphodiesterase 7A1 promoter.

    PubMed Central

    Torras-Llort, Mònica; Azorín, Fernando

    2003-01-01

    In this paper, the human phosphodiesterase 7A1 (h PDE7A1 ) promoter region was identified and functionally characterized. Transient transfection experiments indicated that a 2.9 kb fragment of the h PDE7A1 5'-flanking region, to position -2907, has strong promoter activity in Jurkat T-cells. Deletion analysis showed that the proximal region, up to position -988, contains major cis -regulatory elements of the h PDE7A1 promoter. This minimal promoter region contains a regulatory CpG island which is essential for promoter activity. The CpG island contains three potential cAMP-response-element-binding protein (CREB)-binding sites that, as judged by in vivo dimethyl sulphate (DMS) footprinting, are occupied in Jurkat T-cells. Moreover, over-expression of CREB results in increased promoter activity, but, on the other hand, promoter activity decreases when a dominant-negative form of CREB (KCREB) is over-expressed. In vivo DMS footprinting strongly indicates that other transcription factors, such Ets-2, nuclear factor of activated T-cells 1 (NFAT-1) and nuclear factor kappaB (NF-kappaB), might also contribute to the regulation of h PDE7A1 promoter. Finally, h PDE7A1 promoter was found to be induced by treatment with PMA, but not by treatment with dibutyryl cAMP or forskolin. These results provide insights into the factors and mechanisms that regulate expression of the h PDE7A gene. PMID:12737631

  15. EDRN Pre-Validation of Metabolic Biomarkers of Prostate Cancer: Follow up EDRN Challenge — EDRN Public Portal

    Cancer.gov

    The goal of this EDRN set-asides proposal is to carry out pre-validation studies on sarcosine as a metabolomic biomarker of prostate cancer in urine. Not only does sarcosine have potential as a marker for the early detection of prostate cancer in post-DRE urine specimens-- but since its highest levels are in metastatic disease it might have utility in predicting aggressiveness of clinically localized disease. We will also use these funds to determine if we can add additional metabolites to sarcosine in order to develop a multiplex metabolomic biomarker panel in prostate cancer. In addition to sarcosine, we have 10-12 additional candidate metabolomic biomarkers that could be developed (as seen from our preliminary global metabolite studies).

  16. Characterization of a Maize Wip1 Promoter in Transgenic Plants

    PubMed Central

    Zhang, Shengxue; Lian, Yun; Liu, Yan; Wang, Xiaoqing; Liu, Yunjun; Wang, Guoying

    2013-01-01

    The Maize Wip1 gene encodes a wound-induced Bowman-Birk inhibitor (BBI) protein which is a type of serine protease inhibitor, and its expression is induced by wounding or infection, conferring resistance against pathogens and pests. In this study, the maize Wip1 promoter was isolated and its function was analyzed. Different truncated Wip1 promoters were fused upstream of the GUS reporter gene and transformed into Arabidopsis, tobacco and rice plants. We found that (1) several truncated maize Wip1 promoters led to strong GUS activities in both transgenic Arabidopsis and tobacco leaves, whereas low GUS activity was detected in transgenic rice leaves; (2) the Wip1 promoter was not wound-induced in transgenic tobacco leaves, but was induced by wounding in transgenic rice leaves; (3) the truncated Wip1 promoter had different activity in different organs of transgenic tobacco plants; (4) the transgenic plant leaves containing different truncated Wip1 promoters had low GUS transcripts, even though high GUS protein level and GUS activities were observed; (5) there was one transcription start site of Wip1 gene in maize and two transcription start sites of GUS in Wip1::GUS transgenic lines; (6) the adjacent 35S promoter which is present in the transformation vectors enhanced the activity of the truncated Wip1 promoters in transgenic tobacco leaves, but did not influence the disability of truncated Wip1231 promoter to respond to wounding signals. We speculate that an ACAAAA hexamer, several CAA trimers and several elements similar to ACAATTAC octamer in the 5′-untranslated region might contribute to the strong GUS activity in Wip1231 transgenic lines, meanwhile, compared to the 5′-untranslated region from Wip1231 transgenic lines, the additional upstream open reading frames (uORFs) in the 5′-untranslated region from Wip1737 transgenic lines might contribute to the lower level of GUS transcript and GUS activity. PMID:24322445

  17. Associations of RASSF1A, RARβ, and CDH1 promoter hypermethylation with oral cancer risk

    PubMed Central

    Wen, Guohong; Wang, Huadong; Zhong, Zhaohui

    2018-01-01

    Abstract Background: Oral tumor is a heterogeneous group of tumors, in which it has several different histopathological and molecular features. Recently, genetic and epigenetic alterations are often detected in the development of oral cancer. Gene promoter hypermethylation leads to the silencing of cancer related genes without changes of genes sequence. To clarify the effect of RAS association domain family protein 1a (RASSF1A), retinoic acid receptor beta (RARβ), and E-cadherin (CDH1) promoter hypermethylation on the risk of oral cancer, we performed this meta-analysis. Methods: PubMed, Web of Science, Embase, and Chinese National Knowledge Infrastructure (CNKI) databases were retrieved to identify eligible articles. Stata 12.0 software was used to analyze extracted data of the included articles. Odds ratios (ORs) with the corresponding 95% confidence interval (95% CI) were calculated to evaluate the associations of RASSF1A, RARβ, and CDH1 promoter hypermethylation with oral cancer risk. Results: Around 23 literatures with 29 studies were included in the final meta-analysis, in which 12 studies were about RASSF1A promoter methylation, 4 studies were about RARβ promoter methylation, and 13 studies were about CDH1 promoter methylation. Overall, the results of this meta-analysis showed that there were significant associations between RASSF1A, RARβ, and CDH1 promoter hypermethylation and oral cancer risk (RASSF1A, OR = 11.8, 95% CI = 6.14–22.66; RARβ, OR = 20.35, 95% CI = 5.64–73.39; CDH1, OR = 13.46, 95% CI = 5.31–34.17). In addition, we found that RASSF1A promoter hypermethylation exerted higher frequency in the tongue tumor than other site tumor in mouth (RASSF1A, tongue tumor vs other site tumor in mouth, unmethylation vs methylation, OR = 0.65, 95%CI = 0.44–0.98). Conclusion: RASSF1A, RARβ, and CDH1 promoter hypermethylation might significantly increase the risk of oral cancer. PMID:29538221

  18. E1A promoter of bovine adenovirus type 3.

    PubMed

    Xing, Li; Tikoo, Suresh Kumar

    2006-12-01

    Conserved motifs of eukaryotic gene promoters, such as TATA box and CAAT box sequences, of E1A of human adenoviruses (e.g human adenovirus 5) lie between the left inverted terminal repeat (ITR) and the ATG of E1A. However, analysis of the left end of the bovine adenovirus 3 (BAdV-3) genome revealed that the conserved sequences of the E1A promoter are present only in the ITR. As such, the promoter activity of ITR was tested in the context of a BAdV-3 vector or a plasmid-based system. Different regions of the left end of the BAdV-3 genome initiated transcription of the red fluorescent protein gene in a plasmid-based system. Moreover, BAdV-3 mutants in which the open reading frame of E1A was placed immediately downstream of the ITR produced E1A transcript and could be propagated in non-E1A-complementing Madin-Darby bovine kidney cells. These results suggest that the left ITR contains the sole BAdV-3 E1A promoter.

  19. Selenium source identification and biogeochemical processes controlling selenium in surface water and biota, Kendrick Reclamation Project, Wyoming, U.S.A.

    USGS Publications Warehouse

    Naftz, D.L.; See, R.B.; Ramirez, P.

    1993-01-01

    The major tributaries draining the Kendrick Reclamation Project (KRP) account for an average of 52% of the total Se load measured in the North Platte River downstream from Casper, Wyoming. The Casper Creek drainage basin contributed the largest Se load of the five tributary sites to the North Platte River. The 4-d average Se concentration in water samples from one site in the part of the North Platte River that receives irrigation return flows exceeded the 5 ??g/l U.S. Environmental Protection Agency's aquatic life criterion five time during a 50-d monitoring period in 1989. In agreement with the water-quality data, muscle and liver tissue rom rainbow trout collected from the same part of the North Platte River had Se concentrations exceeding levels known to cause reproductive failure and chronic Se poisoning. On the basis of Se: Cl, 18O/16O and D/H ratios in water from Goose and Rasmus Lee Lakes (closed-basin systems), the large Se concentrations in those lakes were derived by natural evaporation of irrigation water without leaching of soluble forms of Se from soil or rocks. Water samples from Thirtythree Mile Reservoir and Illco Pond (flow-through systems) showed considerable enrichment in Se over evaporative concentration, presumably due to leaching and desorption of Se from soil and rock. The Se: Cl ratios of irrigation drain water collected from the KRP indicate that leaching and desorption of soluble forms of Se from soils and rocks are the dominant processes in drain water. Results of a Wilcoxon matched-pairs test for 43 paired drain-water samples collected during June and August 1988, indicated there is a statistically larger concentration of Se (0.01 significance level) during the June sampling period. The larger concentrations of Se and other chemical constitutents during the early part of the irrigation season probably were due to dissolution of seleniferous salts that have accumulated in soils within the KRP since the last irrigation season. The large

  20. Promotion of PDT efficacy by HA14-1

    NASA Astrophysics Data System (ADS)

    Kessel, David; Price, Michael; Haagenson, Kelly

    2008-02-01

    Photodynamic therapy (PDT) can target the members of the Bcl-2 family that protect cells from the initiation of apoptosis, a well-known death pathway. We examined the ability of HA14-1, a non-peptidic Bcl-2/Bcl-xL antagonist, to promote the efficacy of PDT. The photosensitizer was the porphycene CPO that causes photodamage to Bcl-2 located in the endoplasmic reticulum. Using low PDT doses together with LD5-20 concentrations of HA14-1, we found a marked synergistic effect. These results indicate that such an effect occurs when PDT is coupled with pharmacologic suppression of Bcl-2 function. HA14-1 is an unstable compound that decomposes in aqueous solution. This resulted in a rapid (~60 sec) burst of fluorescence that closely mimicked the properties of many fluorescent probes, but was traced to an effect produced when HA14-1 contacts serum proteins. Other Bcl-2 antagonists that do not produce any intrinsic fluorescence also promoted PDT efficacy. Moreover, briefly storing HA14-1 in aqueous medium until the fluorescent burst is over does not inhibit a subsequent synergistic promotion of PDT efficacy. We conclude that Bcl-2 antagonists can promote the efficacy of low-dose PDT in a manner unrelated to ROS production. The most likely explanation is an enhanced loss of anti-apoptotic Bcl-2 family function such that a threshold for initiation of apoptosis is crossed.

  1. Potential bioremediation of mercury-contaminated substrate using filamentous fungi isolated from forest soil.

    PubMed

    Kurniati, Evi; Arfarita, Novi; Imai, Tsuyoshi; Higuchi, Takaya; Kanno, Ariyo; Yamamoto, Koichi; Sekine, Masahiko

    2014-06-01

    The use of filamentous fungi in bioremediation of heavy metal contamination has been developed recently. This research aims to observe the capability of filamentous fungi isolated from forest soil for bioremediation of mercury contamination in a substrate. Six fungal strains were selected based on their capability to grow in 25 mg/L Hg(2+)-contaminated potato dextrose agar plates. Fungal strain KRP1 showed the highest ratio of growth diameter, 0.831, thus was chosen for further observation. Identification based on colony and cell morphology carried out by 18S rRNA analysis gave a 98% match to Aspergillus flavus strain KRP1. The fungal characteristics in mercury(II) contamination such as range of optimum pH, optimum temperature and tolerance level were 5.5-7 and 25-35°C and 100 mg/L respectively. The concentration of mercury in the media affected fungal growth during lag phases. The capability of the fungal strain to remove the mercury(II) contaminant was evaluated in 100 mL sterile 10 mg/L Hg(2+)-contaminated potato dextrose broth media in 250 mL Erlenmeyer flasks inoculated with 10(8) spore/mL fungal spore suspension and incubation at 30°C for 7 days. The mercury(II) utilization was observed for flasks shaken in a 130 r/min orbital shaker (shaken) and non-shaken flasks (static) treatments. Flasks containing contaminated media with no fungal spores were also provided as control. All treatments were done in triplicate. The strain was able to remove 97.50% and 98.73% mercury from shaken and static systems respectively. A. flavus strain KRP1 seems to have potential use in bioremediation of aqueous substrates containing mercury(II) through a biosorption mechanism. Copyright © 2014 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

  2. Epigenetic silencing of Bim transcription by Spi-1/PU.1 promotes apoptosis resistance in leukaemia

    PubMed Central

    Ridinger-Saison, M; Evanno, E; Gallais, I; Rimmelé, P; Selimoglu-Buet, D; Sapharikas, E; Moreau-Gachelin, F; Guillouf, C

    2013-01-01

    Deregulation of transcriptional networks contributes to haematopoietic malignancies. The transcription factor Spi-1/PU.1 is a master regulator of haematopoiesis and its alteration leads to leukaemia. Spi-1 overexpression inhibits differentiation and promotes resistance to apoptosis in erythroleukaemia. Here, we show that Spi-1 inhibits mitochondrial apoptosis in vitro and in vivo through the transcriptional repression of Bim, a proapoptotic factor. BIM interacts with MCL-1 that behaves as a major player in the survival of the preleukaemic cells. The repression of BIM expression reduces the amount of BIM-MCL-1 complexes, thus increasing the fraction of potentially active antiapoptotic MCL-1. We then demonstrate that Spi-1 represses Bim transcription by binding to the Bim promoter and by promoting the trimethylation of histone 3 on lysine 27 (H3K27me3, a repressive histone mark) on the Bim promoter. The PRC2 repressive complex of Polycomb is directly responsible for the deposit of H3K27me3 mark at the Bim promoter. SUZ12 and the histone methyltransferase EZH2, two PRC2 subunits bind to the Bim promoter at the same location than H3K27me3, distinct of the Spi-1 DNA binding site. As Spi-1 interacts with SUZ12 and EZH2, these results indicate that Spi-1 modulates the activity of PRC2 without directly recruiting the complex to the site of its activity on the chromatin. Our results identify a new mechanism whereby Spi-1 represses transcription and provide mechanistic insights on the antiapoptotic function of a transcription factor mediated by the epigenetic control of gene expression. PMID:23852375

  3. 26 CFR 1.263(b)-1 - Expenditures for advertising or promotion of good will.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 3 2010-04-01 2010-04-01 false Expenditures for advertising or promotion of... advertising or promotion of good will. See § 1.162-14 for the rules applicable to a corporation which has elected to capitalize expenditures for advertising or the promotion of good will under the provisions of...

  4. Far infrared promotes wound healing through activation of Notch1 signaling.

    PubMed

    Hsu, Yung-Ho; Lin, Yuan-Feng; Chen, Cheng-Hsien; Chiu, Yu-Jhe; Chiu, Hui-Wen

    2017-11-01

    The Notch signaling pathway is critically involved in cell proliferation, differentiation, development, and homeostasis. Far infrared (FIR) has an effect that promotes wound healing. However, the underlying molecular mechanisms are unclear. In the present study, we employed in vivo and HaCaT (a human skin keratinocyte cell line) models to elucidate the role of Notch1 signaling in FIR-promoted wound healing. We found that FIR enhanced keratinocyte migration and proliferation. FIR induced the Notch1 signaling pathway in HaCaT cells and in a microarray dataset from the Gene Expression Omnibus database. We next determined the mRNA levels of NOTCH1 in paired normal and wound skin tissues derived from clinical patients using the microarray dataset and Ingenuity Pathway Analysis software. The result indicated that the Notch1/Twist1 axis plays important roles in wound healing and tissue repair. In addition, inhibiting Notch1 signaling decreased the FIR-enhanced proliferation and migration. In a full-thickness wound model in rats, the wounds healed more rapidly and the scar size was smaller in the FIR group than in the light group. Moreover, FIR could increase Notch1 and Delta1 in skin tissues. The activation of Notch1 signaling may be considered as a possible mechanism for the promoting effect of FIR on wound healing. FIR stimulates keratinocyte migration and proliferation. Notch1 in keratinocytes has an essential role in FIR-induced migration and proliferation. NOTCH1 promotes TWIST1-mediated gene expression to assist wound healing. FIR might promote skin wound healing in a rat model. FIR stimulates keratinocyte migration and proliferation. Notch1 in keratinocytes has an essential role in FIR-induced migration and proliferation. NOTCH1 promotes TWIST1-mediated gene expression to assist wound healing. FIR might promote skin wound healing in a rat model.

  5. Engineering Yarrowia lipolytica to express secretory invertase with strong FBA1IN promoter.

    PubMed

    Hong, Seung-Pyo; Seip, John; Walters-Pollak, Dana; Rupert, Ross; Jackson, Raymond; Xue, Zhixiong; Zhu, Quinn

    2012-02-01

    Oleaginous yeast Yarrowia lipolytica is an important host for the production of lipid-derived compounds or heterologous proteins. Selection of strong promoters and effective expression systems is critical for heterologous protein secretion. To search for a strong promoter in Y. lipolytica, activities of FBA1, TDH1 and GPM1 promoters were compared to that of TEF1 promoter by constructing GUS reporter fusions. The FBA1 promoter activity was 2.2 and 5.5 times stronger than the TDH1 and GPM1 promoters, respectively. The FBA1IN promoter (FBA1 sequence of -826 to +169) containing an intron (+64 to +165) showed five-fold higher expression than the FBA1 promoter (-831 to -1). The transcriptional enhancement by the 5'-region within the FBA1 gene was confirmed by GPM1::FBA1 chimeric promoter construction. Using the strong FBA1IN promoter, four different S. cerevisiae SUC2 expression cassettes were tested for the SUC+ phenotype in Y. lipolytica. Functional invertase secretion was facilitated by the Xpr2 prepro-region with an additional 13 amino acids of mature Xpr2, or by the native Suc2 signal sequence. However, these two secretory signals in tandem, or the mature Suc2 with no secretory signal, did not direct secretion of functional invertase. Unlike previously reported Y. lipolytica SUC+ strains, our engineered stains secreted most of invertase into the medium. Copyright © 2011 John Wiley & Sons, Ltd.

  6. Functional significance of SPINK1 promoter variants in chronic pancreatitis.

    PubMed

    Derikx, Monique H M; Geisz, Andrea; Kereszturi, Éva; Sahin-Tóth, Miklós

    2015-05-01

    Chronic pancreatitis is a progressive inflammatory disorder of the pancreas, which often develops as a result of genetic predisposition. Some of the most frequently identified risk factors affect the serine protease inhibitor Kazal type 1 (SPINK1) gene, which encodes a trypsin inhibitor responsible for protecting the pancreas from premature trypsinogen activation. Recent genetic and functional studies indicated that promoter variants in the SPINK1 gene might contribute to disease risk in carriers. Here, we investigated the functional effects of 17 SPINK1 promoter variants using luciferase reporter gene expression assay in four different cell lines, including three pancreatic acinar cell lines (rat AR42J with or without dexamethasone-induced differentiation and mouse 266-6) and human embryonic kidney 293T cells. We found that most variants caused relatively small changes in promoter activity. Surprisingly, however, we observed significant variations in the effects of the promoter variants in the different cell lines. Only four variants exhibited consistently reduced promoter activity in all acinar cell lines, confirming previous reports that variants c.-108G>T, c.-142T>C, and c.-147A>G are risk factors for chronic pancreatitis and identifying c.-52G>T as a novel risk variant. In contrast, variant c.-215G>A, which is linked with the disease-associated splice-site mutation c.194 + 2T>C, caused increased promoter activity, which may mitigate the overall effect of the pathogenic haplotype. Our study lends further support to the notion that sequence evaluation of the SPINK1 promoter region in patients with chronic pancreatitis is justified as part of the etiological investigation. Copyright © 2015 the American Physiological Society.

  7. Suppression of survivin promoter activity by YM155 involves disruption of Sp1-DNA interaction in the survivin core promoter

    PubMed Central

    Cheng, Qiuying; Ling, Xiang; Haller, Andrew; Nakahara, Takahito; Yamanaka, Kentaro; Kita, Aya; Koutoku, Hiroshi; Takeuchi, Masahiro; Brattain, Michael G; Li, Fengzhi

    2012-01-01

    YM155, a novel survivin suppressant, shows potent antitumor activity against various human cancers and is currently in phase II clinical trials. In this study, we investigated whether YM155 selectively inhibits survivin transcription. We hypothesize that inhibition of survivin transcription plays a role in YM155-mediated survivin inhibition. We found that YM155 inhibited survivin promoter activity, while it showed minimal inhibitory effect on four control gene promoters in transfection and luciferase activity assay experiments, indicating its selectivity. Transfection of various survivin promoter-luciferase constructs followed by luciferase assays revealed that the survivin core promoter (269 bp) plays a major role in YM155-mediated inhibitory effects. However, flow cytometry analysis indicated that inhibition of survivin promoter activity by YM155 is cell cycle-independent without G1 cell arrests. Electrophoretic mobility shift assays (EMSA) identified that YM155 abrogates nuclear proteins binding to the region of -149 to -71, in which Sp1 is a major candidate, and that YM155 treatment induces Sp1 re-subcellular localization without inhibiting its expression. Forced expression of Sp1 neutralized YM155-mediated downregulation of survivin promoter activity. Consistently, mutation of the identified Sp1 sites in the oligonucleotide probe diminished DNA-protein interactions in EMSA experiments, and mutation of the Sp1 sites in the survivin promoter-luciferase construct diminished survivin promoter activity. These findings indicate that YM155 inhibition of survivin expression is at least in part through its inhibition of survivin transcription by disruption of Sp1 interaction with the region of -149 to -71 in the survivin core promoter. PMID:22773958

  8. Enhancer activity of Helitron in sericin-1 gene promoter from Bombyx mori.

    PubMed

    Huang, Ke; Li, Chun-Feng; Wu, Jie; Wei, Jun-Hong; Zou, Yong; Han, Min-Jin; Zhou, Ze-Yang

    2016-06-01

    Sericin is a kind of water-soluble protein expressed specifically in the middle silk gland of Bombyx mori. When the sericin-1 gene promoter was cloned and a transgenic vector was constructed to express a foreign protein, a specific Helitron, Bmhel-8, was identified in the sericin-1 gene promoter sequence in some genotypes of Bombyx mori and Bombyx mandarina. Given that the Bmhel-8 Helitron transposon was present only in some genotypes, it could be the source of allelic variation in the sericin-1 promoter. The length of the sericin-1 promoter sequence is approximately 1063 or 643 bp. The larger size of the sequence or allele is ascribed to the presence of Bmhel-8. Silkworm genotypes can be homozygous for either the shorter or larger promoter sequence or heterozygous, containing both alleles. Bmhel-8 in the sericin-1 promoter exhibits enhancer activity, as demonstrated by a dual-luciferase reporter system in BmE cell lines. Furthermore, Bmhel-8 displays enhancer activity in a sericin-1 promoter-driven gene expression system but does not regulate the tissue-specific expression of sericin-1. © 2016 Institute of Zoology, Chinese Academy of Sciences.

  9. The USP1-UAF1 complex interacts with RAD51AP1 to promote homologous recombination repair.

    PubMed

    Cukras, Scott; Lee, Euiho; Palumbo, Emily; Benavidez, Pamela; Moldovan, George-Lucian; Kee, Younghoon

    2016-10-01

    USP1 deubiquitinating enzyme and its stoichiometric binding partner UAF1 play an essential role in promoting DNA homologous recombination (HR) repair in response to various types of DNA damaging agents. Deubiquitination of FANCD2 may be attributed to the key role of USP1-UAF1 complex in regulating HR repair, however whether USP1-UAF1 promotes HR repair independently of FANCD2 deubiquitination is not known. Here we show evidence that the USP1-UAF1 complex has a FANCD2-independent function in promoting HR repair. Proteomic search of UAF1-interacting proteins revealed that UAF1 associates with RAD51AP1, a RAD51-interacting protein implicated in HR repair. We show that UAF1 mediates the interaction between USP1 and RAD51AP1, and that depletion of USP1 or UAF1 led to a decreased stability of RAD51AP1. Protein interaction mapping analysis identified some key residues within RAD51AP1 required for interacting with the USP1-UAF1 complex. Cells expressing the UAF1 interaction-deficient mutant of RAD51AP1 show increased chromosomal aberrations in response to Mitomycin C treatment. Moreover, similar to the RAD51AP1 depleted cells, the cells expressing UAF1-interaction deficient RAD51AP1 display persistent RAD51 foci following DNA damage exposure, indicating that these factors regulate a later step during the HR repair. These data altogether suggest that the USP1-UAF1 complex promotes HR repair via multiple mechanisms: through FANCD2 deubiquitination, as well as by interacting with RAD51AP1.

  10. The USP1-UAF1 complex interacts with RAD51AP1 to promote homologous recombination repair

    PubMed Central

    Cukras, Scott; Lee, Euiho; Palumbo, Emily; Benavidez, Pamela; Moldovan, George-Lucian; Kee, Younghoon

    2016-01-01

    ABSTRACT USP1 deubiquitinating enzyme and its stoichiometric binding partner UAF1 play an essential role in promoting DNA homologous recombination (HR) repair in response to various types of DNA damaging agents. Deubiquitination of FANCD2 may be attributed to the key role of USP1-UAF1 complex in regulating HR repair, however whether USP1-UAF1 promotes HR repair independently of FANCD2 deubiquitination is not known. Here we show evidence that the USP1-UAF1 complex has a FANCD2-independent function in promoting HR repair. Proteomic search of UAF1-interacting proteins revealed that UAF1 associates with RAD51AP1, a RAD51-interacting protein implicated in HR repair. We show that UAF1 mediates the interaction between USP1 and RAD51AP1, and that depletion of USP1 or UAF1 led to a decreased stability of RAD51AP1. Protein interaction mapping analysis identified some key residues within RAD51AP1 required for interacting with the USP1-UAF1 complex. Cells expressing the UAF1 interaction-deficient mutant of RAD51AP1 show increased chromosomal aberrations in response to Mitomycin C treatment. Moreover, similar to the RAD51AP1 depleted cells, the cells expressing UAF1-interaction deficient RAD51AP1 display persistent RAD51 foci following DNA damage exposure, indicating that these factors regulate a later step during the HR repair. These data altogether suggest that the USP1-UAF1 complex promotes HR repair via multiple mechanisms: through FANCD2 deubiquitination, as well as by interacting with RAD51AP1. PMID:27463890

  11. Human papillomavirus type 16 E7 oncoprotein mediates CCNA1 promoter methylation.

    PubMed

    Chalertpet, Kanwalat; Pakdeechaidan, Watcharapong; Patel, Vyomesh; Mutirangura, Apiwat; Yanatatsaneejit, Pattamawadee

    2015-10-01

    Human papillomavirus (HPV) oncoproteins drive distinctive promoter methylation patterns in cancer. However, the underlying mechanism remains to be elucidated. Cyclin A1 (CCNA1) promoter methylation is strongly associated with HPV-associated cancer. CCNA1 methylation is found in HPV-associated cervical cancers, as well as in head and neck squamous cell cancer. Numerous pieces of evidence suggest that E7 may drive CCNA1 methylation. First, the CCNA1 promoter is methylated in HPV-positive epithelial lesions after transformation. Second, the CCNA1 promoter is methylated at a high level when HPV is integrated into the human genome. Finally, E7 has been shown to interact with DNA methyltransferase 1 (Dnmt1). Here, we sought to determine the mechanism by which E7 increases methylation in cervical cancer by using CCNA1 as a gene model. We investigated whether E7 induces CCNA1 promoter methylation, resulting in the loss of expression. Using both E7 knockdown and overexpression approaches in SiHa and C33a cells, our data showed that CCNA1 promoter methylation decreases with a corresponding increase in expression in E7 siRNA-transfected cells. By contrast, CCNA1 promoter methylation was augmented with a corresponding reduction in expression in E7-overexpressing cells. To confirm whether the binding of the E7-Dnmt1 complex to the CCNA1 promoter induced methylation and loss of expression, ChIP assays were carried out in E7-, del CR3-E7 and vector control-overexpressing C33a cells. The data showed that E7 induced CCNA1 methylation by forming a complex with Dnmt1 at the CCNA1 promoter, resulting in the subsequent reduction of expression in cancers. It is interesting to further explore the genome-wide mechanism of E7 oncoprotein-mediated DNA methylation. © 2015 The Authors. Cancer Science published by Wiley Publishing Asia Pty Ltd on behalf of Japanese Cancer Association.

  12. Determinants that specify the integration pattern of retrotransposon Tf1 in the fbp1 promoter of Schizosaccharomyces pombe.

    PubMed

    Majumdar, Anasuya; Chatterjee, Atreyi Ghatak; Ripmaster, Tracy L; Levin, Henry L

    2011-01-01

    Long terminal repeat (LTR) retrotransposons are closely related to retroviruses and, as such, are important models for the study of viral integration and target site selection. The transposon Tf1 of Schizosaccharomyces pombe integrates with a strong preference for the promoters of polymerase II (Pol II)-transcribed genes. Previous work in vivo with plasmid-based targets revealed that the patterns of insertion were promoter specific and highly reproducible. To determine which features of promoters are recognized by Tf1, we studied integration in a promoter that has been characterized. The promoter of fbp1 has two upstream activating sequences, UAS1 and UAS2. We found that integration was targeted to two windows, one 180 nucleotides (nt) upstream and the other 30 to 40 nt downstream of UAS1. A series of deletions in the promoter showed that the integration activities of these two regions functioned autonomously. Integration assays of UAS2 and of a synthetic promoter demonstrated that strong promoter activity alone was not sufficient to direct integration. The factors that modulate the transcription activities of UAS1 and UAS2 include the activators Atf1p, Pcr1p, and Rst2p as well as the repressors Tup11p, Tup12p, and Pka1p. Strains lacking each of these proteins revealed that Atf1p alone mediated the sites of integration. These data indicate that Atf1p plays a direct and specific role in targeting integration in the promoter of fbp1.

  13. Targeting Sphingosine-1-Phosphate Axis in Obesity-Promoted Breast Cancer

    DTIC Science & Technology

    2016-05-01

    AWARD NUMBER: W81XWH-14-1-0071 TITLE: Targeting Sphingosine-1-Phosphate Axis in Obesity -Promoted Breast Cancer PRINCIPAL INVESTIGATOR...5a. CONTRACT NUMBER Targeting Sphingosine-1-Phosphate Axis in Obesity -Promoted Breast Cancer 5b. GRANT NUMBER W81XWH-14-1-0071 5c. PROGRAM ELEMENT...13. SUPPLEMENTARY NOTES 14. ABSTRACT Obesity , which induces low-grade inflammation, is a known risk factor for worse prognosis in many cancers

  14. Sp1 upregulates the proximal promoter activity of the mouse collagen α1(XI) gene (Col11a1) in chondrocytes.

    PubMed

    Watanabe, Keijirou; Hida, Mariko; Sasaki, Takako; Yano, Hiroyuki; Kawano, Kenji; Yoshioka, Hidekatsu; Matsuo, Noritaka

    2016-02-01

    Type XI collagen is a cartilage-specific extracellular matrix, and is important for collagen fibril formation and skeletal morphogenesis. We have previously reported that NF-Y regulated the proximal promoter activity of the mouse collagen α1(XI) gene (Col11a1) in chondrocytes (Hida et. al. In Vitro Cell. Dev. Biol. Anim. 2014). However, the mechanism of the Col11a1 gene regulation in chondrocytes has not been fully elucidated. In this study, we further characterized the proximal promoter activity of the mouse Col11a1 gene in chondrocytes. Cell transfection experiments with deletion and mutation constructs indicated that the downstream region of the NF-Y binding site (-116 to +1) is also necessary to regulate the proximal promoter activity of the mouse Col11a1 gene. This minimal promoter region has no TATA box and GC-rich sequence; we therefore examined whether the GC-rich sequence (-96 to -67) is necessary for the transcription regulation of the Col11a1 gene. Luciferase assays using a series of mutation constructs exhibited that the GC-rich sequence is a critical element of Col11a1 promoter activity in chondrocytes. Moreover, in silico analysis of this region suggested that one of the most effective candidates was transcription factor Sp1. Consistent with the prediction, overexpression of Sp1 significantly increased the promoter activity. Furthermore, knockdown of Sp1 expression by siRNA transfection suppressed the proximal promoter activity and the expression of endogenous transcript of the mouse Col11a1 gene. Taken together, these results indicate that the transcription factor Sp1 upregulates the proximal promoter activity of the mouse Col11a1 gene in chondrocytes.

  15. The Human Immunodeficiency Virus 1 ASP RNA promotes viral latency by recruiting the Polycomb Repressor Complex 2 and promoting nucleosome assembly

    PubMed Central

    Zapata, Juan C.; Campilongo, Federica; Barclay, Robert A.; DeMarino, Catherine; Iglesias-Ussel, Maria D.; Kashanchi, Fatah; Romerio, Fabio

    2017-01-01

    Various epigenetic marks at the HIV-1 5′LTR suppress proviral expression and promote latency. Cellular antisense transcripts known as long noncoding RNAs (lncRNAs) recruit the polycomb repressor complex 2 (PRC2) to gene promoters, which catalyzes trimethylation of lysine 27 on histone H3 (H3K27me3), thus promoting nucleosome assembly and suppressing gene expression. We found that an HIV-1 antisense transcript expressed from the 3′LTR and encoding the antisense protein ASP promotes proviral latency. Expression of ASP RNA reduced HIV-1 replication in Jurkat cells. Moreover, ASP RNA expression promoted the establishment and maintenance of HIV-1 latency in Jurkat E4 cells. We show that this transcript interacts with and recruits PRC2 to the HIV-1 5′LTR, increasing accumulation of the suppressive epigenetic mark H3K27me3, while reducing RNA Polymerase II and thus proviral transcription. Altogether, our results suggest that the HIV-1 ASP transcript promotes epigenetic silencing of the HIV-1 5′LTR and proviral latency through the PRC2 pathway. PMID:28340355

  16. Aberrant Promoter Methylation and Expression of UTF1 during Cervical Carcinogenesis

    PubMed Central

    Deplus, Rachel; Lampe, Xavier; Krusy, Nathalie; Calonne, Emilie; Delbecque, Katty; Kridelka, Frederic; Fuks, François; Ennaji, My Mustapha; Delvenne, Philippe

    2012-01-01

    Promoter methylation profiles are proposed as potential prognosis and/or diagnosis biomarkers in cervical cancer. Up to now, little is known about the promoter methylation profile and expression pattern of stem cell (SC) markers during tumor development. In this study, we were interested to identify SC genes methylation profiles during cervical carcinogenesis. A genome-wide promoter methylation screening revealed a strong hypermethylation of Undifferentiated cell Transcription Factor 1 (UTF1) promoter in cervical cancer in comparison with normal ectocervix. By direct bisulfite pyrosequencing of DNA isolated from liquid-based cytological samples, we showed that UTF1 promoter methylation increases with lesion severity, the highest level of methylation being found in carcinoma. This hypermethylation was associated with increased UTF1 mRNA and protein expression. By using quantitative RT-PCR and Western Blot, we showed that both UTF1 mRNA and protein are present in epithelial cancer cell lines, even in the absence of its two main described regulators Oct4A and Sox2. Moreover, by immunofluorescence, we confirmed the nuclear localisation of UTF1 in cell lines. Surprisingly, direct bisulfite pyrosequencing revealed that the inhibition of DNA methyltransferase by 5-aza-2′-deoxycytidine was associated with decreased UTF1 gene methylation and expression in two cervical cancer cell lines of the four tested. These findings strongly suggest that UTF1 promoter methylation profile might be a useful biomarker for cervical cancer diagnosis and raise the questions of its role during epithelial carcinogenesis and of the mechanisms regulating its expression. PMID:22880087

  17. Genistein promotes DNA demethylation of the steroidogenic factor 1 (SF-1) promoter in endometrial stromal cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Matsukura, Hiroshi, E-mail: hmatsukura.epi@mri.tmd.ac.jp; Aisaki, Ken-ichi; Igarashi, Katsuhide

    2011-08-26

    Highlights: {yields} Genistein (GEN) is a phytoestrogen found in soy products. {yields} GEN demethylated/unsilenced the steroidogenic factor 1 gene in endometrial tissue. {yields} GEN thus altered mRNA expression in uteri of ovariectomized (OVX) mice. {yields} A high-resolution melting assay was used to screen for epigenetic change. {yields} We isolated an endometrial cell clone that was epigenetically modulated by GEN. -- Abstract: It has recently been demonstrated that genistein (GEN), a phytoestrogen in soy products, is an epigenetic modulator in various types of cells; but its effect on endometrium has not yet been determined. We investigated the effects of GEN onmore » mouse uterine cells, in vivo and in vitro. Oral administration of GEN for 1 week induced mild proliferation of the endometrium in ovariectomized (OVX) mice, which was accompanied by the induction of steroidogenic factor 1 (SF-1) gene expression. GEN administration induced demethylation of multiple CpG sites in the SF-1 promoter; these sites are extensively methylated and thus silenced in normal endometrium. The GEN-mediated promoter demethylation occurred predominantly on the luminal side, as opposed to myometrium side, indicating that the epigenetic change was mainly shown in regenerated cells. Primary cultures of endometrial stromal cell colonies were screened for GEN-mediated alterations of DNA methylation by a high-resolution melting (HRM) method. One out of 20 colony-forming cell clones showed GEN-induced demethylation of SF-1. This clone exhibited a high proliferation capacity with continuous colony formation activity through multiple serial clonings. We propose that only a portion of endometrial cells are capable of receiving epigenetic modulation by GEN.« less

  18. Retrotransposon Tf1 is targeted to pol II promoters by transcription activators

    PubMed Central

    Leem, Young-Eun; Ripmaster, Tracy; Kelly, Felice; Ebina, Hirotaka; Heincelman, Marc; Zhang, Ke; Grewal, Shiv I. S.; Hoffman, Charles S.; Levin, Henry L.

    2008-01-01

    SUMMARY The LTR-retrotransposon Tf1 preserves the coding capacity of its host Schizosaccharomyces pombe by integrating upstream of open reading frames (ORFs). To determine which features of the target sites were recognized by the transposon, we introduced plasmids containing candidate insertion sites into S. pombe and mapped the positions of integration. We found that Tf1 was targeted specifically to the promoters of pol II transcribed genes. A detailed analysis of integration in plasmids that contained either ade6 or fbp1 revealed insertions occurred in the promoters at positions where transcription factors bound. Further experiments revealed that the activator Atf1p and its binding site were required for directing integration to the promoter of fbp1. An interaction between Tf1 integrase and Atf1p was observed indicating that integration at fbp1 was mediated by the activator bound to its promoter. Surprisingly we found Tf1 contained sequences that activated transcription and these substituted for elements of the ade6 promoter disrupted by integration. PMID:18406330

  19. Retrotransposon Tf1 is targeted to Pol II promoters by transcription activators.

    PubMed

    Leem, Young-Eun; Ripmaster, Tracy L; Kelly, Felice D; Ebina, Hirotaka; Heincelman, Marc E; Zhang, Ke; Grewal, Shiv I S; Hoffman, Charles S; Levin, Henry L

    2008-04-11

    The LTR-retrotransposon Tf1 preserves the coding capacity of its host Schizosaccharomyces pombe by integrating upstream of open reading frames (ORFs). To determine which features of the target sites were recognized by the transposon, we introduced plasmids containing candidate insertion sites into S. pombe and mapped the positions of integration. We found that Tf1 was targeted specifically to the promoters of Pol II-transcribed genes. A detailed analysis of integration in plasmids that contained either ade6 or fbp1 revealed insertions occurred in the promoters at positions where transcription factors bound. Further experiments revealed that the activator Atf1p and its binding site were required for directing integration to the promoter of fbp1. An interaction between Tf1 integrase and Atf1p was observed, indicating that integration at fbp1 was mediated by the activator bound to its promoter. Surprisingly, we found Tf1 contained sequences that activated transcription, and these substituted for elements of the ade6 promoter disrupted by integration.

  20. The Human Immunodeficiency Virus 1 ASP RNA promotes viral latency by recruiting the Polycomb Repressor Complex 2 and promoting nucleosome assembly.

    PubMed

    Zapata, Juan C; Campilongo, Federica; Barclay, Robert A; DeMarino, Catherine; Iglesias-Ussel, Maria D; Kashanchi, Fatah; Romerio, Fabio

    2017-06-01

    Various epigenetic marks at the HIV-1 5'LTR suppress proviral expression and promote latency. Cellular antisense transcripts known as long noncoding RNAs (lncRNAs) recruit the polycomb repressor complex 2 (PRC2) to gene promoters, which catalyzes trimethylation of lysine 27 on histone H3 (H3K27me3), thus promoting nucleosome assembly and suppressing gene expression. We found that an HIV-1 antisense transcript expressed from the 3'LTR and encoding the antisense protein ASP promotes proviral latency. Expression of ASP RNA reduced HIV-1 replication in Jurkat cells. Moreover, ASP RNA expression promoted the establishment and maintenance of HIV-1 latency in Jurkat E4 cells. We show that this transcript interacts with and recruits PRC2 to the HIV-1 5'LTR, increasing accumulation of the suppressive epigenetic mark H3K27me3, while reducing RNA Polymerase II and thus proviral transcription. Altogether, our results suggest that the HIV-1 ASP transcript promotes epigenetic silencing of the HIV-1 5'LTR and proviral latency through the PRC2 pathway. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  1. 53BP1 promotes microhomology-mediated end-joining in G1-phase cells

    PubMed Central

    Xiong, Xiahui; Du, Zhanwen; Wang, Ying; Feng, Zhihui; Fan, Pan; Yan, Chunhong; Willers, Henning; Zhang, Junran

    2015-01-01

    Alternative non-homologous end joining (alt-NHEJ) was originally identified as a backup repair mechanism in the absence of classical NHEJ (c-NHEJ) factors but recent studies have demonstrated that alt-NHEJ is active even when c-NHEJ as well as homologous recombination is available. The functions of 53BP1 in NHEJ processes are not well understood. Here, we report that 53BP1 promotes DNA double-strand break (DSB) repair and genomic stability not only in c-NHEJ-proficient but also -deficient human G1-phase cells. Using an array of repair substrates we show that these effects of 53BP1 are correlated with a promotion of microhomology-mediated end-joining (MMEJ), a subtype of alt-NHEJ, in G1-phase. Consistent with a specific role in MMEJ we confirm that 53BP1 status does not affect c-NHEJ. 53BP1 supports sequence deletion during MMEJ consistent with a putative role in facilitating end-resection. Interestingly, promotion of MMEJ by 53BP1 in G1-phase cells is only observed in the presence of functional BRCA1. Depletion of both 53BP1 and BRCA1 increases repair needing microhomology usage and augments loss of DNA sequence, suggesting that MMEJ is a highly regulated DSB repair process. Together, these findings significantly expand our understanding of the cell-cycle-dependent roles of 53BP1 in DSB repair. PMID:25586219

  2. RCP-driven α5β1 recycling suppresses Rac and promotes RhoA activity via the RacGAP1-IQGAP1 complex.

    PubMed

    Jacquemet, Guillaume; Green, David M; Bridgewater, Rebecca E; von Kriegsheim, Alexander; Humphries, Martin J; Norman, Jim C; Caswell, Patrick T

    2013-09-16

    Inhibition of αvβ3 or expression of mutant p53 promotes invasion into fibronectin (FN)-containing extracellular matrix (ECM) by enhancing Rab-coupling protein (RCP)-dependent recycling of α5β1 integrin. RCP and α5β1 cooperatively recruit receptor tyrosine kinases, including EGFR1, to regulate their trafficking and downstream signaling via protein kinase B (PKB)/Akt, which, in turn, promotes invasive migration. In this paper, we identify a novel PKB/Akt substrate, RacGAP1, which is phosphorylated as a consequence of RCP-dependent α5β1 trafficking. Phosphorylation of RacGAP1 promotes its recruitment to IQGAP1 at the tips of invasive pseudopods, and RacGAP1 then locally suppresses the activity of the cytoskeletal regulator Rac and promotes the activity of RhoA in this subcellular region. This Rac to RhoA switch promotes the extension of pseudopodial processes and invasive migration into FN-containing matrices, in a RhoA-dependent manner. Thus, the localized endocytic trafficking of α5β1 within the tips of invasive pseudopods elicits signals that promote the reorganization of the actin cytoskeleton, protrusion, and invasion into FN-rich ECM.

  3. Frequent somatic TERT promoter mutations and CTNNB1 mutations in hepatocellular carcinoma.

    PubMed

    Lee, Seung Eun; Chang, Seong-Hwan; Kim, Wook Youn; Lim, So Dug; Kim, Wan Seop; Hwang, Tea Sook; Han, Hye Seung

    2016-10-25

    Genetic alterations of TERT and CTNNB1 have been documented in hepatocellular carcinoma. TERT promoter mutations are the earliest genetic events in the multistep process of hepatocarcinogenesis related to cirrhosis. However, analyses of TERT promoter and CTNNB1 mutations in hepatocellular carcinoma tumor samples have not been performed in the Korean population, where hepatitis B virus-related hepatocellular carcinoma is prevalent. In order to identify the role of TERT promoter and CTNNB1 mutations in the hepatocarcinogenesis and pathogenesis of recurrent hepatocellular carcinoma, we performed the sequence analyses in 140 hepatocellular nodules (including 107 hepatocellular carcinomas), and 8 pairs of matched primary and relapsed hepatocellular carcinomas. TERT promoter and CTNNB1 mutations were only observed in hepatocellular carcinomas but not in precursor lesions. Of 109 patients with hepatocellular carcinoma, 41 (39.0%) and 15 (14.6%) harbored TERT and CTNNB1 mutations, respectively. TERT promotermutations were significantly more frequent in hepatocellular carcinomas related to hepatitis C virus infection (5/6; 83.3%) compared to tumors of other etiologies (P = 0.001). In two cases, discordance in TERT promoter mutation status was observed between the primary and the corresponding recurrent hepatocellular carcinoma. The two patients with discordant cases had early relapses. In conclusion, we identified TERT promoter and CTNNB1 mutations as the most frequent somatic genetic alterations observed in hepatocellular carcinoma, indicating its pivotal role in hepatocarcinogenesis. Furthermore, we suggest the possibility of intratumoral genetic heterogeneity of TERT promoter mutations in hepatocellular carcinoma as indicated by the discordance in TERT promoter mutations between primary and corresponding recurrent hepatocellular carcinoma.

  4. Selective Activation of Sphingosine 1-Phosphate Receptors 1 and 3 Promotes Local Microvascular Network Growth

    PubMed Central

    Sefcik, Lauren S.; Petrie Aronin, Caren E.; Awojoodu, Anthony O.; Shin, Soo J.; Mac Gabhann, Feilim; MacDonald, Timothy L.; Wamhoff, Brian R.; Lynch, Kevin R.; Peirce, Shayn M.

    2011-01-01

    Proper spatial and temporal regulation of microvascular remodeling is critical to the formation of functional vascular networks, spanning the various arterial, venous, capillary, and collateral vessel systems. Recently, our group has demonstrated that sustained release of sphingosine 1-phosphate (S1P) from biodegradable polymers promotes microvascular network growth and arteriolar expansion. In this study, we employed S1P receptor-specific compounds to activate and antagonize different combinations of S1P receptors to elucidate those receptors most critical for promotion of pharmacologically induced microvascular network growth. We show that S1P1 and S1P3 receptors act synergistically to enhance functional network formation via increased functional length density, arteriolar diameter expansion, and increased vascular branching in the dorsal skinfold window chamber model. FTY720, a potent activator of S1P1 and S1P3, promoted a 107% and 153% increase in length density 3 and 7 days after implantation, respectively. It also increased arteriolar diameters by 60% and 85% 3 and 7 days after implantation. FTY720-stimulated branching in venules significantly more than unloaded poly(D, L-lactic-co-glycolic acid). When implanted on the mouse spinotrapezius muscle, FTY720 stimulated an arteriogenic response characterized by increased tortuosity and collateralization of branching microvascular networks. Our results demonstrate the effectiveness of S1P1 and S1P3 receptor-selective agonists (such as FTY720) in promoting microvascular growth for tissue engineering applications. PMID:20874260

  5. Promoter methylation assay of SASH1 gene in breast cancer.

    PubMed

    Sheyu, Lin; Hui, Liu; Junyu, Zhang; Jiawei, Xu; Honglian, Wang; Qing, Sang; Hengwei, Zhang; Xuhui, Guo; Qinghe, Xing; Lin, He

    2013-01-01

    To analyze the relationship between the expression of SASH1 and its methylation level of SASH1 gene promoter in human breast cancer. Expression levels of SASH1 were examined in breast cancer tissues and adjacent normal tissues with immunohistochemistry and with real time PCR (RT-PCR) methylation analysis was performed with MassArray. Immunohistochemistry showed that SASH1 expression was strongly reduced in breast cancer compared with adjacent normal tissues. Quantitative methylation analysis by MassArray revealed that CpG sites in SASH1 promoter shared similar methylation pattern in tumor tissue and adjacent normal tissue. The CpG sites with significant difference in methylation level were CpG_26.27 and CpG_54.55. Moreover, 5-aza-2'-deoxycytidine (5-Aza-dc) treatment of tumor cell line MDA-MB-231 caused significant elevation of SASH1 mRNA. Based on these data, we propose that increase of DNA methylation level in the promoter region of gene SASH1, particularly CpG_26.27 or CpG_54.55 sites, possibly repressed SASH1 expression in breast cancer.

  6. Immune activation with peptide assemblies carrying Lewis y tumor-associated carbohydrate antigen.

    PubMed

    Yamazaki, Yuji; Watabe, Naoki; Obata, Hiroaki; Hara, Eri; Ohmae, Masashi; Kimura, Shunsaku

    2017-02-01

    Molecular assemblies varying morphologies in a wide range from spherical micelle, nanosheet, curved sheet, nanotube and vesicle were prepared and loaded with Lewis y (Le y ) tumor-associated carbohydrate antigen on the assembly surface. The molecular assemblies were composed of poly(sarcosine) m -block-poly(L-lactic acid) 30 (m = 15 or 50, Lactosome), poly(sarcosine) m -block-(D/L-Leu-Aib) n (m = 22 or 30, n = 6 or 8) and their combinations. The molecular assemblies carrying Le y on the surface were administered in BALB/c nu/nu mice. The major epitopes of the molecular assemblies are commonly Le y and poly(sarcosine). IgM productions upon administrations of the molecular assemblies were assayed by ELISA, showing that anti-poly(sarcosine) IgM was highly produced by Lactosome of spherical micelle but with a negligible amount of anti-Le y IgM. On the other hand, the nanosheet of the interdigitated monolayer triggered the production of anti-Le y IgM but with less anti-poly(sarcosine) IgM production. Taken together, IgM specificity differs according to the molecular environment of the epitopes in the molecular assemblies. The antigenicity of poly(sarcosine) was augmented in polymeric micelle providing loose environment for B cells to penetrate in, whereas a high density of Le y on the molecular assembly was required for anti-Le y IgM production. The antigenicity of Le y is therefore dependent on the molecular assemblies on which Le y is displayed on the surface. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd.

  7. SIRT1 promotes metastasis of human osteosarcoma cells

    PubMed Central

    Zhang, Ning; Xie, Tao; Xian, Miao; Wang, Yi-Jie; Li, Heng-Yuan

    2016-01-01

    Pulmonary metastasis is the leading cause of mortality in patients with osteosarcoma; however, the underlying mechanism remains unclear. The NAD+-dependent deacetylase, sirtuin 1 (SIRT1), has been reported to play a key role in carcinogenesis through deacetylation of important regulatory proteins. Here, we report that SIRT1 promotes osteosarcoma metastasis by regulating the expression of metastatic-associated genes. The SIRT1 protein was significantly upregulated in most primary osteosarcoma tumours, compared with normal tissues, and the SIRT1 expression level may be coupled with metastatic risk in patients with osteosarcoma. Moreover, the results of cell migration and wound-healing assays further suggested that higher expression of SIRT1 promoted invasive activity of osteosarcoma cells. Importantly, downregulating SIRT1 with shRNA inhibited the migration ability of osteosarcoma cells in vitro and suppressed tumour lung metastasis in mice. Finally, a gene expression analysis showed that knockdown of SIRT1 profoundly activated translation of its downstream pathway, particularly at migration and invasion. In summary, high levels of SIRT1 may be a biomarker for a high metastatic rate in osteosarcoma patients; inhibiting SIRT1 could be a potent therapeutic intervention for these patients. PMID:27793039

  8. ADH1B promotes mesothelial clearance and ovarian cancer infiltration.

    PubMed

    Gharpure, Kshipra M; Lara, Olivia D; Wen, Yunfei; Pradeep, Sunila; LaFargue, Chris; Ivan, Cristina; Rupaimoole, Rajesha; Hu, Wei; Mangala, Lingegowda S; Wu, Sherry Y; Nagaraja, Archana S; Baggerly, Keith; Sood, Anil K

    2018-05-18

    Primary debulking surgery followed by adjuvant chemotherapy is the standard treatment for ovarian cancer. Residual disease after primary surgery is associated with poor patient outcome. Previously, we discovered ADH1B to be a molecular biomarker of residual disease. In the current study, we investigated the functional role of ADH1B in promoting ovarian cancer cell invasiveness and contributing to residual disease. We discovered that ADH1B overexpression leads to a more infiltrative cancer cell phenotype, promotes metastasis, increases the adhesion of cancer cells to mesothelial cells, and increases extracellular matrix degradation. Live cell imaging revealed that ADH1B-overexpressing cancer cells efficiently cleared the mesothelial cell layer compared to control cells. Moreover, gene array analysis revealed that ADH1B affects several pathways related to the migration and invasion of cancer cells. We also discovered that hypoxia increases ADH1B expression in ovarian cancer cells. Collectively, these findings indicate that ADH1B plays an important role in the pathways that promote ovarian cancer cell infiltration and may increase the likelihood of residual disease following surgery.

  9. Regulatory single nucleotide polymorphisms (rSNPs) at the promoters 1A and 1B of the human APC gene.

    PubMed

    Matveeva, Marina Yu; Kashina, Elena V; Reshetnikov, Vasily V; Bryzgalov, Leonid O; Antontseva, Elena V; Bondar, Natalia P; Merkulova, Tatiana I

    2016-12-22

    Germline mutations in the coding sequence of the tumour suppressor APC gene give rise to familial adenomatous polyposis (which leads to colorectal cancer) and are associated with many other oncopathologies. The loss of APC function because of deletion of putative promoter 1A or 1B also results in the development of colorectal cancer. Since the regions of promoters 1A and 1B contain many single nucleotide polymorphisms (SNPs), the aim of this study was to perform functional analysis of some of these SNPs by means of an electrophoretic mobility shift assay (EMSA) and a luciferase reporter assay. First, it was shown that both putative promoters of APC (1A and 1B) drive transcription in an in vitro reporter experiment. From eleven randomly selected SNPs of promoter 1A and four SNPs of promoter 1B, nine and two respectively showed differential patterns of binding of nuclear proteins to oligonucleotide probes corresponding to alternative alleles. The luciferase reporter assay showed that among the six SNPs tested, the rs75612255 C allele and rs113017087 C allele in promoter 1A as well as the rs138386816 T allele and rs115658307 T allele in promoter 1B significantly increased luciferase activity in the human erythromyeloblastoid leukaemia cell line K562. In human colorectal cancer HCT-116 cells, none of the substitutions under study had any effect, with the exception of minor allele G of rs79896135 in promoter 1B. This allele significantly decreased the luciferase reporter's activity CONCLUSION: Our results indicate that many SNPs in APC promoters 1A and 1B are functionally relevant and that allele G of rs79896135 may be associated with the predisposition to colorectal cancer.

  10. Tetramethylpyrazine-Inducible Promoter Region from Rhodococcus jostii TMP1.

    PubMed

    Stanislauskienė, Rūta; Kutanovas, Simonas; Kalinienė, Laura; Bratchikov, Maksim; Meškys, Rolandas

    2018-06-25

    An inducible promoter region, P TTMP (tetramethylpyrazine [TTMP]), has been identified upstream of the tpdABC operon, which contains the genes required for the initial degradation of 2,3,5,6-tetramethylpyrazine in Rhodococcus jostii TMP1 bacteria. In this work, the promoter region was fused with the gene for the enhanced green fluorescent protein (EGFP) to investigate the activity of P TTMP by measuring the fluorescence of bacteria. The highest promoter activity was observed when bacteria were grown in a nutrient broth (NB) medium supplemented with 5 mM 2,3,5,6-tetramethylpyrazine for 48 h. Using a primer extension reaction, two transcriptional start sites for tpdA were identified, and the putative −35 and −10 promoter motifs were determined. The minimal promoter along with two 15 bp long direct repeats and two 7 bp inverted sequences were identified. Also, the influence of the promoter elements on the activity of P TTMP were determined using site-directed mutagenesis. Furthermore, P TTMP was shown to be induced by pyrazine derivatives containing methyl groups in the 2- and 5-positions of the heterocyclic ring, in the presence of the LuxR family transcriptional activator TpdR.

  11. YB-1 overexpression promotes a TGF-β1-induced epithelial–mesenchymal transition via Akt activation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ha, Bin; Lee, Eun Byul; Cui, Jun

    2015-03-06

    The Y-box binding protein-1 (YB-1) is a transcription/translation regulatory protein, and the expression thereof is associated with cancer aggressiveness. In the present study, we explored the regulatory effects of YB-1 during the transforming growth factor-β1 (TGF-β1)-induced epithelial-to-mesenchymal transition (EMT) in lung adenocarcinoma cells. Downregulation of YB-1 increased E-cadherin promoter activity, and upregulation of YB-1 decreased promoter activity, suggesting that the YB-1 level may be correlated with the EMT. TGF-β1 induced YB-1 expression, and TGF-β1 translocated cytosolic YB-1 into the nucleus. YB-1 overexpression promoted TGF-β1-induced downregulation of epithelial markers, upregulation of mesenchymal markers, and cell migration. Moreover, YB-1 overexpression enhanced themore » expression of E-cadherin transcriptional repressors via TGF-β1-induced Akt activation. Our findings afford new insights into the role played by YB-1 in the TGF-β1 signaling pathway. - Highlights: • YB-1 regulates E-cadherin expression in A549 cells. • TGF-β1 induces upregulating and nuclear localization of YB-1. • YB-1 overexpression accelerates TGF-β1-induced EMT and cell migration. • YB-1 regulates Snail and Slug expression via Akt activation.« less

  12. A sequential multi-target Mps1 phosphorylation cascade promotes spindle checkpoint signaling.

    PubMed

    Ji, Zhejian; Gao, Haishan; Jia, Luying; Li, Bing; Yu, Hongtao

    2017-01-10

    The master spindle checkpoint kinase Mps1 senses kinetochore-microtubule attachment and promotes checkpoint signaling to ensure accurate chromosome segregation. The kinetochore scaffold Knl1, when phosphorylated by Mps1, recruits checkpoint complexes Bub1-Bub3 and BubR1-Bub3 to unattached kinetochores. Active checkpoint signaling ultimately enhances the assembly of the mitotic checkpoint complex (MCC) consisting of BubR1-Bub3, Mad2, and Cdc20, which inhibits the anaphase-promoting complex or cyclosome bound to Cdc20 (APC/C Cdc20 ) to delay anaphase onset. Using in vitro reconstitution, we show that Mps1 promotes APC/C inhibition by MCC components through phosphorylating Bub1 and Mad1. Phosphorylated Bub1 binds to Mad1-Mad2. Phosphorylated Mad1 directly interacts with Cdc20. Mutations of Mps1 phosphorylation sites in Bub1 or Mad1 abrogate the spindle checkpoint in human cells. Therefore, Mps1 promotes checkpoint activation through sequentially phosphorylating Knl1, Bub1, and Mad1. This sequential multi-target phosphorylation cascade makes the checkpoint highly responsive to Mps1 and to kinetochore-microtubule attachment.

  13. An inter-order horizontal gene transfer event enables the catabolism of compatible solutes by Colwellia psychrerythraea 34H.

    PubMed

    Collins, R Eric; Deming, Jody W

    2013-07-01

    Colwellia is a genus of mostly psychrophilic halophilic Gammaproteobacteria frequently isolated from polar marine sediments and sea ice. In exploring the capacity of Colwellia psychrerythraea 34H to survive and grow in the liquid brines of sea ice, we detected a duplicated 37 kbp genomic island in its genome based on the abnormally high G + C content. This island contains an operon encoding for heterotetrameric sarcosine oxidase and is located adjacent to several genes used in the serial demethylation of glycine betaine, a compatible solute commonly used for osmoregulation, to dimethylglycine, sarcosine, and glycine. Molecular clock inferences of important events in the adaptation of C. psychrerythraea 34H to compatible solute utilization reflect the geological evolution of the polar regions. Validating genomic predictions, C. psychrerythraea 34H was shown to grow on defined media containing either choline or glycine betaine, and on a medium with sarcosine as the sole organic source of carbon and nitrogen. Growth by 8 of 9 tested Colwellia species on a newly developed sarcosine-based defined medium suggested that the ability to catabolize glycine betaine (the catabolic precursor of sarcosine) is likely widespread in the genus Colwellia. This capacity likely provides a selective advantage to Colwellia species in cold, salty environments like sea ice, and may have contributed to the ability of Colwellia to invade these extreme niches.

  14. RCP-driven α5β1 recycling suppresses Rac and promotes RhoA activity via the RacGAP1–IQGAP1 complex

    PubMed Central

    Jacquemet, Guillaume; Green, David M.; Bridgewater, Rebecca E.; von Kriegsheim, Alexander; Humphries, Martin J.; Norman, Jim C.

    2013-01-01

    Inhibition of αvβ3 or expression of mutant p53 promotes invasion into fibronectin (FN)-containing extracellular matrix (ECM) by enhancing Rab-coupling protein (RCP)–dependent recycling of α5β1 integrin. RCP and α5β1 cooperatively recruit receptor tyrosine kinases, including EGFR1, to regulate their trafficking and downstream signaling via protein kinase B (PKB)/Akt, which, in turn, promotes invasive migration. In this paper, we identify a novel PKB/Akt substrate, RacGAP1, which is phosphorylated as a consequence of RCP-dependent α5β1 trafficking. Phosphorylation of RacGAP1 promotes its recruitment to IQGAP1 at the tips of invasive pseudopods, and RacGAP1 then locally suppresses the activity of the cytoskeletal regulator Rac and promotes the activity of RhoA in this subcellular region. This Rac to RhoA switch promotes the extension of pseudopodial processes and invasive migration into FN-containing matrices, in a RhoA-dependent manner. Thus, the localized endocytic trafficking of α5β1 within the tips of invasive pseudopods elicits signals that promote the reorganization of the actin cytoskeleton, protrusion, and invasion into FN-rich ECM. PMID:24019536

  15. FBI-1 enhances ETS-1 signaling activity and promotes proliferation of human colorectal carcinoma cells.

    PubMed

    Zhu, Min; Li, Mingyang; Zhang, Fan; Feng, Fan; Chen, Weihao; Yang, Yutao; Cui, Jiajun; Zhang, Dong; Linghu, Enqiang

    2014-01-01

    In this study, we investigated a potential regulatory role of FBI-1 in transcription factor activity of ETS-1. The protein interaction was identified between ETS-1 and FBI-1 in lovo cells. The accumulating data showed that FBI-1 promoted the recruitment of ETS-1 to endogenous promoter of its target genes and increase ETS-1 accumulation in the nuclear. Our work also indicated that the FBI-1 enhances ETS-1 transcription factor activity via down-regulating p53-mediated inhibition on ETS-1. Further, FBI-1 plays a role in regulation of colorectal carcinoma cells proliferation. These findings supported that FBI-1 might be a potential molecule target for treating colorectal carcinoma.

  16. FBI-1 Enhances ETS-1 Signaling Activity and Promotes Proliferation of Human Colorectal Carcinoma Cells

    PubMed Central

    Chen, Weihao; Yang, Yutao; Cui, Jiajun; Zhang, Dong; Linghu, Enqiang

    2014-01-01

    In this study, we investigated a potential regulatory role of FBI-1 in transcription factor activity of ETS-1. The protein interaction was identified between ETS-1 and FBI-1 in lovo cells. The accumulating data showed that FBI-1 promoted the recruitment of ETS-1 to endogenous promoter of its target genes and increase ETS-1 accumulation in the nuclear. Our work also indicated that the FBI-1 enhances ETS-1 transcription factor activity via down-regulating p53-mediated inhibition on ETS-1. Further, FBI-1 plays a role in regulation of colorectal carcinoma cells proliferation. These findings supported that FBI-1 might be a potential molecule target for treating colorectal carcinoma. PMID:24857950

  17. Study of the Role of siRNA Mediated Promoter Methylation in DNMT3B Knockdown and Alteration of Promoter Methylation of CDH1, GSTP1 Genes in MDA-MB -453 Cell Line.

    PubMed

    Naghitorabi, Mojgan; Mir Mohammad Sadeghi, Hamid; Mohammadi Asl, Javad; Rabbani, Mohammad; Jafarian-Dehkordi, Abbas

    2017-01-01

    Promoter methylation is one of the main epigenetic mechanisms that leads to the inactivation of tumor suppressor genes during carcinogenesis. Due to the reversible nature of DNA methylation, many studies have been performed to correct theses epigenetic defects by inhibiting DNA methyltransferases (DNMTs). In this case novel therapeutics especially siRNA oligonucleotides have been used to specifically knock down the DNMTs at mRNA level. Also many studies have focused on transcriptional gene silencing in mammalian cells via siRNA mediated promoter methylation. The present study was designed to assess the role of siRNA mediated promoter methylation in DNMT3B knockdown and alteration of promoter methylation of Cadherin-1 (CDH1), Glutathione S-Transferase Pi 1(GSTP1), and DNMT3B genes in MDA-MB-453 cell line. MDA-MB-453 cells were transfected with siDNMT targeting DNMT3B promoter and harvested at 24 and 48 h post transfection to monitor gene silencing and promoter methylation respectively. DNMT3B expression was monitored by quantitative RT-PCR method. Promoter methylation was quantitatively evaluated using differential high resolution melting analysis. A non-significant 20% reduction in DNMT3B mRNA level was shown only after first transfection with siDNMT, which was not reproducible. Promoter methylation levels of DNMT3B, CDH1, and GSTP1 were detected at about 15%, 70% and 10% respectively, in the MDA-MB-453 cell line, with no significant change after transfection. Our results indicated that siDNMT sequence were not able to affect promoter methylation and silencing of DNMT3B in MDA-MB-453 cells. However, quantitation of methylation confirmed a hypermethylated phenotype at CDH1 and GSTP1 promoters as well as a differential methylation pattern at DNMT3B promoter in breast cancer.

  18. Determinants That Specify the Integration Pattern of Retrotransposon Tf1 in the fbp1 Promoter of Schizosaccharomyces pombe ▿ †

    PubMed Central

    Majumdar, Anasuya; Chatterjee, Atreyi Ghatak; Ripmaster, Tracy L.; Levin, Henry L.

    2011-01-01

    Long terminal repeat (LTR) retrotransposons are closely related to retroviruses and, as such, are important models for the study of viral integration and target site selection. The transposon Tf1 of Schizosaccharomyces pombe integrates with a strong preference for the promoters of polymerase II (Pol II)-transcribed genes. Previous work in vivo with plasmid-based targets revealed that the patterns of insertion were promoter specific and highly reproducible. To determine which features of promoters are recognized by Tf1, we studied integration in a promoter that has been characterized. The promoter of fbp1 has two upstream activating sequences, UAS1 and UAS2. We found that integration was targeted to two windows, one 180 nucleotides (nt) upstream and the other 30 to 40 nt downstream of UAS1. A series of deletions in the promoter showed that the integration activities of these two regions functioned autonomously. Integration assays of UAS2 and of a synthetic promoter demonstrated that strong promoter activity alone was not sufficient to direct integration. The factors that modulate the transcription activities of UAS1 and UAS2 include the activators Atf1p, Pcr1p, and Rst2p as well as the repressors Tup11p, Tup12p, and Pka1p. Strains lacking each of these proteins revealed that Atf1p alone mediated the sites of integration. These data indicate that Atf1p plays a direct and specific role in targeting integration in the promoter of fbp1. PMID:20980525

  19. Epigenetic regulation of the glucocorticoid receptor promoter 1(7) in adult rats.

    PubMed

    Witzmann, Simone R; Turner, Jonathan D; Mériaux, Sophie B; Meijer, Onno C; Muller, Claude P

    2012-11-01

    Regulation of glucocorticoid receptor (GR) levels is an important stress adaptation mechanism. Transcription factor Nfgi-a and environmentally induced Gr promoter 1 7 methylation have been implicated in fine-tuning the expression of Gr 1 7 transcripts. Here, we investigated Gr promoter 1 7 methylation and Gr 1 7 expression in adult rats exposed to either acute or chronic stress paradigms. A strong negative correlation was observed between the sum of promoter-wide methylation levels and Gr 1 7 transcript levels, independent of the stressor. Methylation of individual sites did not, however, correlate with transcript levels. This suggested that promoter 1 7 was directly regulated by promoter-wide DNA methylation. Although acute stress increased Ngfi-a expression in the hypothalamic paraventricular nucleus (PVN), Gr 1 7 transcript levels remained unaffected despite low methylation levels. Acute stress had little effect on these low methylation levels, except at four hippocampal CpGs. Chronic stress altered the corticosterone response to an acute stressor. In the adrenal and pituitary glands, but not in the brain, this was accompanied by an increase in methylation levels in orchestrated clusters rather than individual CpGs. PVN methylation levels, unaffected by acute or chronic stress, were significantly more variable within- than between-groups, suggesting that they were instated probably during the perinatal period and represent a pre-established trait. Thus, in addition to the known perinatal programming, the Gr 1 7 promoter is epigenetically regulated by chronic stress in adulthood, and retains promoter-wide tissue-specific plasticity. Differences in methylation susceptibility between the PVN in the perinatal period and the peripheral HPA axis tissues in adulthood may represent an important "trait" vs. "state" regulation of the Gr gene.

  20. Serum Bilirubin Levels and Promoter Variations in HMOX1 and UGT1A1 Genes in Patients with Fabry Disease.

    PubMed

    Jirásková, Alena; Bortolussi, Giulia; Dostálová, Gabriela; Eremiášová, Lenka; Golaň, Lubor; Danzig, Vilém; Linhart, Aleš; Vítek, Libor

    2017-01-01

    The aim of our study was to assess the possible relationships among heme oxygenase (HMOX), bilirubin UDP-glucuronosyl transferase (UGT1A1) promoter gene variations, serum bilirubin levels, and Fabry disease (FD). The study included 56 patients with FD (M : F ratio = 0.65) and 185 healthy individuals. Complete standard laboratory and clinical work-up was performed on all subjects, together with the determination of total peroxyl radical-scavenging capacity. The (GT)n and (TA)n dinucleotide variations in the HMOX1 and UGT1A1 gene promoters, respectively, were determined by DNA fragment analysis. Compared to controls, patients with FD had substantially lower serum bilirubin levels (12.0 versus 8.85  μ mol/L, p = 0.003) and also total antioxidant capacity ( p < 0.05), which showed a close positive relationship with serum bilirubin levels ( p = 0.067) and the use of enzyme replacement therapy ( p = 0.036). There was no association between HMOX1 gene promoter polymorphism and manifestation of FD. However, the presence of the TA 7 allele UGT1A1 gene promoter, responsible for higher systemic bilirubin levels, was associated with a twofold lower risk of manifestation of FD (OR = 0.51, 95% CI = 0.27-0.97, p = 0.038). Markedly lower serum bilirubin levels in FD patients seem to be due to bilirubin consumption during increased oxidative stress, although UGT1A1 promoter gene polymorphism may modify the manifestation of FD as well.

  1. Prx1 and 3.2 kb Col1a1 promoters target distinct bone cell populations in transgenic mice

    PubMed Central

    Ouyang, Zhufeng; Chen, Zhijun; Ishikawa, Masakazu; Yue, Xiuzhen; Kawanami, Aya; Leahy, Patrick; Greenfield, Edward M.; Murakami, Shunichi

    2014-01-01

    Bones consist of a number of cell types including osteoblasts and their precursor cells at various stages of differentiation. To analyze cellular organization within the bone, we generated Col1a1CreER-DsRed transgenic mice that express, in osteoblasts, CreER and DsRed under the control of a mouse 3.2 kb Col1a1 promoter. We further crossed Col1a1CreER-DsRed mice with Prx1CreER-GFP mice that express CreER and GFP in osteochondro progenitor cells under the control of a 2.4 kb Prx1 promoter. Since the 3.2 kb Col1a1 promoter becomes active in osteoblasts at early stages of differentiation, and Prx1CreER-GFP-expressing periosteal cells show endogenous Col1a1 expression, we expected to find a cell population in which both the 2.4 kb Prx1 promoter and the 3.2 kb Col1a1 promoter are active. However, our histological and flow cytometric analyses demonstrated that these transgenes are expressed in distinct cell populations. In the periosteum of long bones, Col1a1CreER-DsRed is expressed in the innermost layer directly lining the bone surface, while Prx1CreER-GFP-expressing cells are localized immediately outside of the Col1a1CreER-DsRed-expressing osteoblasts. In the calvaria, Prx1CreER-GFP-expressing cells are also localized in the cranial suture mesenchyme. Our experiments further showed that Col1a1CreER-DsRed-expressing cells lack chondrogenic potential, while the Prx1CreER-GFP-expressing cells show both chondrogenic and osteogenic potential. Our results indicate that Col1a1CreER-DsRed-expressing cells are committed osteoblasts, while Prx1CreER-GFP-expressing cells are osteochondro progenitor cells. The Prx1CreER-GFP and Col1a1CreER-DsRed transgenes will offer novel approaches for analyzing lineage commitment and early stages of osteoblast differentiation under physiologic and pathologic conditions. PMID:24513582

  2. RNAi-Mediated Knockdown of IKK1 in Transgenic Mice Using a Transgenic Construct Containing the Human H1 Promoter

    PubMed Central

    Moreno-Maldonado, Rodolfo; Murillas, Rodolfo; Page, Angustias; Suarez-Cabrera, Cristian; Alameda, Josefa P.; Bravo, Ana; Casanova, M. Llanos

    2014-01-01

    Inhibition of gene expression through siRNAs is a tool increasingly used for the study of gene function in model systems, including transgenic mice. To achieve perdurable effects, the stable expression of siRNAs by an integrated transgenic construct is necessary. For transgenic siRNA expression, promoters transcribed by either RNApol II or III (such as U6 or H1 promoters) can be used. Relatively large amounts of small RNAs synthesis are achieved when using RNApol III promoters, which can be advantageous in knockdown experiments. To study the feasibility of H1 promoter-driven RNAi-expressing constructs for protein knockdown in transgenic mice, we chose IKK1 as the target gene. Our results indicate that constructs containing the H1 promoter are sensitive to the presence of prokaryotic sequences and to transgene position effects, similar to RNApol II promoters-driven constructs. We observed variable expression levels of transgenic siRNA among different tissues and animals and a reduction of up to 80% in IKK1 expression. Furthermore, IKK1 knockdown led to hair follicle alterations. In summary, we show that constructs directed by the H1 promoter can be used for knockdown of genes of interest in different organs and for the generation of animal models complementary to knockout and overexpression models. PMID:24523631

  3. Isolation and characterization of the Jatropha curcas APETALA1 (JcAP1) promoter conferring preferential expression in inflorescence buds.

    PubMed

    Tao, Yan-Bin; He, Liang-Liang; Niu, Longjian; Xu, Zeng-Fu

    2016-08-01

    The 1.5 kb JcAP1 promoter from the biofuel plant Jatropha curcas is predominantly active in the inflorescence buds of transgenic plants, in which the -1313/-1057 region is essential for maintaining the activity. Arabidopsis thaliana APETALA1 (AP1) is a MADS-domain transcription factor gene that functions primarily in flower development. We isolated a homolog of AP1 from Jatropha curcas (designated JcAP1), which was shown to exhibit flower-specific expression in Jatropha. JcAP1 is first expressed in inflorescence buds and continues to be primarily expressed in the sepals. We isolated a 1.5 kb JcAP1 promoter and evaluated its activity in transgenic Arabidopsis and Jatropha using the β-glucuronidase (GUS) reporter gene. In transgenic Arabidopsis and Jatropha, the inflorescence buds exhibited notable GUS activity, whereas the sepals did not. Against expectations, the JcAP1 promoter was active in the anthers of Arabidopsis and Jatropha and was highly expressed in Jatropha seeds. An analysis of promoter deletions in transgenic Arabidopsis revealed that deletion of the -1313/-1057 region resulted in loss of JcAP1 promoter activity in the inflorescence buds and increased activity in the anthers. These results suggested that some regulatory sequences in the -1313/-1057 region are essential for maintaining promoter activity in inflorescence buds and can partly suppress activity in the anthers. Based on these findings, we hypothesized that other elements located upstream of the 1.5 kb JcAP1 promoter may be required for flower-specific activation. The JcAP1 promoter characterized in this study can be used to drive transgene expression in both the inflorescence buds and seeds of Jatropha.

  4. Bovine herpesvirus 1 productive infection and immediate early transcription unit 1 promoter are stimulated by the synthetic corticosteroid dexamethasone.

    PubMed

    Kook, Insun; Henley, Caitlin; Meyer, Florencia; Hoffmann, Federico G; Jones, Clinton

    2015-10-01

    The primary site for life-long latency of bovine herpesvirus 1 (BHV-1) is sensory neurons. The synthetic corticosteroid dexamethasone consistently induces reactivation from latency; however the mechanism by which corticosteroids mediate reactivation is unclear. In this study, we demonstrate for the first time that dexamethasone stimulates productive infection, in part, because the BHV-1 genome contains more than 100 potential glucocorticoid receptor (GR) response elements (GREs). Immediate early transcription unit 1 (IEtu1) promoter activity, but not IEtu2 or VP16 promoter activity, was stimulated by dexamethasone. Two near perfect consensus GREs located within the IEtu1 promoter were necessary for dexamethasone-mediated stimulation. Electrophoretic mobility shift assays and chromatin immunoprecipitation studies demonstrated that the GR interacts with IEtu1 promoter sequences containing the GREs. Although we hypothesize that DEX-mediated stimulation of IEtu1 promoter activity is important during productive infection and perhaps reactivation from latency, stress likely has pleiotropic effects on virus-infected cells. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. A sequential multi-target Mps1 phosphorylation cascade promotes spindle checkpoint signaling

    PubMed Central

    Ji, Zhejian; Gao, Haishan; Jia, Luying; Li, Bing; Yu, Hongtao

    2017-01-01

    The master spindle checkpoint kinase Mps1 senses kinetochore-microtubule attachment and promotes checkpoint signaling to ensure accurate chromosome segregation. The kinetochore scaffold Knl1, when phosphorylated by Mps1, recruits checkpoint complexes Bub1–Bub3 and BubR1–Bub3 to unattached kinetochores. Active checkpoint signaling ultimately enhances the assembly of the mitotic checkpoint complex (MCC) consisting of BubR1–Bub3, Mad2, and Cdc20, which inhibits the anaphase-promoting complex or cyclosome bound to Cdc20 (APC/CCdc20) to delay anaphase onset. Using in vitro reconstitution, we show that Mps1 promotes APC/C inhibition by MCC components through phosphorylating Bub1 and Mad1. Phosphorylated Bub1 binds to Mad1–Mad2. Phosphorylated Mad1 directly interacts with Cdc20. Mutations of Mps1 phosphorylation sites in Bub1 or Mad1 abrogate the spindle checkpoint in human cells. Therefore, Mps1 promotes checkpoint activation through sequentially phosphorylating Knl1, Bub1, and Mad1. This sequential multi-target phosphorylation cascade makes the checkpoint highly responsive to Mps1 and to kinetochore-microtubule attachment. DOI: http://dx.doi.org/10.7554/eLife.22513.001 PMID:28072388

  6. PTP1B inhibitor promotes endothelial cell motility by activating the DOCK180/Rac1 pathway.

    PubMed

    Wang, Yuan; Yan, Feng; Ye, Qing; Wu, Xiao; Jiang, Fan

    2016-04-07

    Promoting endothelial cell (EC) migration is important not only for therapeutic angiogenesis, but also for accelerating re-endothelialization after vessel injury. Several recent studies have shown that inhibition of protein tyrosine phosphatase 1B (PTP1B) may promote EC migration and angiogenesis by enhancing the vascular endothelial growth factor receptor-2 (VEGFR2) signalling. In the present study, we demonstrated that PTP1B inhibitor could promote EC adhesion, spreading and migration, which were abolished by the inhibitor of Rac1 but not RhoA GTPase. PTP1B inhibitor significantly increased phosphorylation of p130Cas, and the interactions among p130Cas, Crk and DOCK180; whereas the phosphorylation levels of focal adhesion kinase, Src, paxillin, or Vav2 were unchanged. Gene silencing of DOCK180, but not Vav2, abrogated the effects of PTP1B inhibitor on EC motility. The effects of PTP1B inhibitor on EC motility and p130Cas/DOCK180 activation persisted in the presence of the VEGFR2 antagonist. In conclusion, we suggest that stimulation of the DOCK180 pathway represents an alternative mechanism of PTP1B inhibitor-stimulated EC motility, which does not require concomitant VEGFR2 activation as a prerequisite. Therefore, PTP1B inhibitor may be a useful therapeutic strategy for promoting EC migration in cardiovascular patients in which the VEGF/VEGFR functions are compromised.

  7. The use of trimethylamine N-oxide as a primary precipitating agent and related methylamine osmolytes as cryoprotective agents for macromolecular crystallography

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Marshall, Haley; Venkat, Murugappan; Hti Lar Seng, Nang San

    2012-01-01

    The stabilizing osmolyte trimethylamine N-oxide (TMAO) is shown to be an efficient primary precipitant for protein crystal growth. In addition to TMAO, two other methylamine osmolytes, sarcosine and betaine, are shown to be effective cryoprotective agents for protein crystal cooling. Both crystallization and cryoprotection are often bottlenecks for high-resolution X-ray structure determination of macromolecules. Methylamine osmolytes are known stabilizers of protein structure. One such osmolyte, trimethylamine N-oxide (TMAO), has seen occasional use as an additive to improve macromolecular crystal quality and has recently been shown to be an effective cryoprotective agent for low-temperature data collection. Here, TMAO and the relatedmore » osmolytes sarcosine and betaine are investigated as primary precipitating agents for protein crystal growth. Crystallization experiments were undertaken with 14 proteins. Using TMAO, seven proteins crystallized in a total of 13 crystal forms, including a new tetragonal crystal form of trypsin. The crystals diffracted well, and eight of the 13 crystal forms could be effectively cryocooled as grown with TMAO as an in situ cryoprotective agent. Sarcosine and betaine produced crystals of four and two of the 14 proteins, respectively. In addition to TMAO, sarcosine and betaine were effective post-crystallization cryoprotective agents for two different crystal forms of thermolysin. Precipitation reactions of TMAO with several transition-metal ions (Fe{sup 3+}, Co{sup 2+}, Cu{sup 2+} and Zn{sup 2+}) did not occur with sarcosine or betaine and were inhibited for TMAO at lower pH. Structures of proteins from TMAO-grown crystals and from crystals soaked in TMAO, sarcosine or betaine were determined, showing osmolyte binding in five of the 12 crystals tested. When an osmolyte was shown to bind, it did so near the protein surface, interacting with water molecules, side chains and backbone atoms, often at crystal contacts.« less

  8. Metal cleaner poisoning

    MedlinePlus

    Metal cleaners contain organic compounds called hydrocarbons, including: 1,2-butylene oxide Boric acid Cocoyl sarcosine Dicarboxylic fatty acid Dimethoxymethane Dodecanedioic acid N-propyl bromide Sodium hydroxide T-butanol

  9. Mit1 Transcription Factor Mediates Methanol Signaling and Regulates the Alcohol Oxidase 1 (AOX1) Promoter in Pichia pastoris*

    PubMed Central

    Wang, Xiaolong; Wang, Qi; Wang, Jinjia; Bai, Peng; Shi, Lei; Shen, Wei; Zhou, Mian; Zhou, Xiangshan; Zhang, Yuanxing; Cai, Menghao

    2016-01-01

    The alcohol oxidase 1 (AOX1) promoter (PAOX1) of Pichia pastoris is the most powerful and commonly used promoter for driving protein expression. However, mechanisms regulating its transcriptional activity are unclear. Here, we identified a Zn(II)2Cys6-type methanol-induced transcription factor 1 (Mit1) and elucidated its roles in regulating PAOX1 activity in response to glycerol and methanol. Mit1 regulated the expression of many genes involved in methanol utilization pathway, including AOX1, but did not participate in peroxisome proliferation and transportation of peroxisomal proteins during methanol metabolism. Structural analysis of Mit1 by performing domain deletions confirmed its specific and critical role in the strict repression of PAOX1 in glycerol medium. Importantly, Mit1, Mxr1, and Prm1, which positively regulated PAOX1 in response to methanol, were bound to PAOX1 at different sites and did not interact with each other. However, these factors cooperatively activated PAOX1 through a cascade. Mxr1 mainly functioned during carbon derepression, whereas Mit1 and Prm1 functioned during methanol induction, with Prm1 transmitting methanol signal to Mit1 by binding to the MIT1 promoter (PMIT1), thus increasingly expressing Mit1 and subsequently activating PAOX1. PMID:26828066

  10. Promoter architecture and transcriptional regulation of Abf1-dependent ribosomal protein genes in Saccharomyces cerevisiae

    PubMed Central

    Fermi, Beatrice; Bosio, Maria Cristina; Dieci, Giorgio

    2016-01-01

    In Saccharomyces cerevisiae, ribosomal protein gene (RPG) promoters display binding sites for either Rap1 or Abf1 transcription factors. Unlike Rap1-associated promoters, the small cohort of Abf1-dependent RPGs (Abf1-RPGs) has not been extensively investigated. We show that RPL3, RPL4B, RPP1A, RPS22B and RPS28A/B share a common promoter architecture, with an Abf1 site upstream of a conserved element matching the sequence recognized by Fhl1, a transcription factor which together with Ifh1 orchestrates Rap1-associated RPG regulation. Abf1 and Fhl1 promoter association was confirmed by ChIP and/or gel retardation assays. Mutational analysis revealed a more severe requirement of Abf1 than Fhl1 binding sites for RPG transcription. In the case of RPS22B an unusual Tbf1 binding site promoted both RPS22B and intron-hosted SNR44 expression. Abf1-RPG down-regulation upon TOR pathway inhibition was much attenuated at defective mutant promoters unable to bind Abf1. TORC1 inactivation caused the expected reduction of Ifh1 occupancy at RPS22B and RPL3 promoters, but unexpectedly it entailed largely increased Abf1 association with Abf1-RPG promoters. We present evidence that Abf1 recruitment upon nutritional stress, also observed for representative ribosome biogenesis genes, favours RPG transcriptional rescue upon nutrient replenishment, thus pointing to nutrient-regulated Abf1 dynamics at promoters as a novel mechanism in ribosome biogenesis control. PMID:27016735

  11. Clinical Implications of Promoter Hypermethylation in RASSF1A and MGMT in Retinoblastoma1

    PubMed Central

    Choy, Kwong Wai; Lee, Tom C; Cheung, Kin Fai; Fan, Dorothy S P; Lo, Kwok Wai; Beaverson, Katherine L; Abramson, David H; Lam, Dennis S C; Yu, Christopher B O; Pang, Chi Pui

    2005-01-01

    Abstract We investigated the epigenetic silencing and genetic changes of the RAS-associated domain family 1A (RASSF1A) gene and the O6-methylguanine-DNA methyltransferase (MGMT) gene in retinoblastoma. We extracted DNA from microdissected tumor and normal retina tissues of the same patient in 68 retinoblastoma cases. Promoter methylation in RASSF1A and MGMT was analyzed by methylation-specific PCR, RASSF1A sequence alterations in all coding exons by direct DNA sequencing, and RASSF1A expression by RT-PCR. Cell cycle staging was analyzed by flow cytometry. We detected RASSF1A promoter hypermethylation in 82% of retinoblastoma, in tumor tissues only but not in adjacent normal retinal tissue cells. There was no expression of RASSF1A transcripts in all hypermethylated samples, but RASSF1A transcripts were restored after 5-aza-2′-deoxycytidine treatment with no changes in cell cycle or apoptosis. No mutation in the RASSF1A sequence was found. MGMT hypermethylation was present in 15% of theretinoblastoma samples, and the absence of MGMT hypermethylation was associated (P = .002) with retinoblastoma at advanced Reese-Ellsworth tumor stage. Our results revealed a high RASSF1A hypermethylation frequency in retinoblastoma. The correlation of MGMT inactivation by promoter hypermethylation with lower-stage diseases indicated that MGMT hypermethylation provides useful prognostic information. Epigenetic mechanism plays an important role in the progression of retinoblastoma. PMID:15799820

  12. Reduced expression of APC-1B but not APC-1A by the deletion of promoter 1B is responsible for familial adenomatous polyposis.

    PubMed

    Yamaguchi, Kiyoshi; Nagayama, Satoshi; Shimizu, Eigo; Komura, Mitsuhiro; Yamaguchi, Rui; Shibuya, Tetsuo; Arai, Masami; Hatakeyama, Seira; Ikenoue, Tsuneo; Ueno, Masashi; Miyano, Satoru; Imoto, Seiya; Furukawa, Yoichi

    2016-05-24

    Germline mutations in the tumor suppressor gene APC are associated with familial adenomatous polyposis (FAP). Here we applied whole-genome sequencing (WGS) to the DNA of a sporadic FAP patient in which we did not find any pathological APC mutations by direct sequencing. WGS identified a promoter deletion of approximately 10 kb encompassing promoter 1B and exon1B of APC. Additional allele-specific expression analysis by deep cDNA sequencing revealed that the deletion reduced the expression of the mutated APC allele to as low as 11.2% in the total APC transcripts, suggesting that the residual mutant transcripts were driven by other promoter(s). Furthermore, cap analysis of gene expression (CAGE) demonstrated that the deleted promoter 1B region is responsible for the great majority of APC transcription in many tissues except the brain. The deletion decreased the transcripts of APC-1B to 39-45% in the patient compared to the healthy controls, but it did not decrease those of APC-1A. Different deletions including promoter 1B have been reported in FAP patients. Taken together, our results strengthen the evidence that analysis of structural variations in promoter 1B should be considered for the FAP patients whose pathological mutations are not identified by conventional direct sequencing.

  13. LMO1 Synergizes with MYCN to Promote Neuroblastoma Initiation and Metastasis.

    PubMed

    Zhu, Shizhen; Zhang, Xiaoling; Weichert-Leahey, Nina; Dong, Zhiwei; Zhang, Cheng; Lopez, Gonzalo; Tao, Ting; He, Shuning; Wood, Andrew C; Oldridge, Derek; Ung, Choong Yong; van Ree, Janine H; Khan, Amish; Salazar, Brittany M; Lummertz da Rocha, Edroaldo; Zimmerman, Mark W; Guo, Feng; Cao, Hong; Hou, Xiaonan; Weroha, S John; Perez-Atayde, Antonio R; Neuberg, Donna S; Meves, Alexander; McNiven, Mark A; van Deursen, Jan M; Li, Hu; Maris, John M; Look, A Thomas

    2017-09-11

    A genome-wide association study identified LMO1, which encodes an LIM-domain-only transcriptional cofactor, as a neuroblastoma susceptibility gene that functions as an oncogene in high-risk neuroblastoma. Here we show that dβh promoter-mediated expression of LMO1 in zebrafish synergizes with MYCN to increase the proliferation of hyperplastic sympathoadrenal precursor cells, leading to a reduced latency and increased penetrance of neuroblastomagenesis. The transgenic expression of LMO1 also promoted hematogenous dissemination and distant metastasis, which was linked to neuroblastoma cell invasion and migration, and elevated expression levels of genes affecting tumor cell-extracellular matrix interaction, including loxl3, itga2b, itga3, and itga5. Our results provide in vivo validation of LMO1 as an important oncogene that promotes neuroblastoma initiation, progression, and widespread metastatic dissemination. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Promoter architecture and transcriptional regulation of Abf1-dependent ribosomal protein genes in Saccharomyces cerevisiae.

    PubMed

    Fermi, Beatrice; Bosio, Maria Cristina; Dieci, Giorgio

    2016-07-27

    In Saccharomyces cerevisiae, ribosomal protein gene (RPG) promoters display binding sites for either Rap1 or Abf1 transcription factors. Unlike Rap1-associated promoters, the small cohort of Abf1-dependent RPGs (Abf1-RPGs) has not been extensively investigated. We show that RPL3, RPL4B, RPP1A, RPS22B and RPS28A/B share a common promoter architecture, with an Abf1 site upstream of a conserved element matching the sequence recognized by Fhl1, a transcription factor which together with Ifh1 orchestrates Rap1-associated RPG regulation. Abf1 and Fhl1 promoter association was confirmed by ChIP and/or gel retardation assays. Mutational analysis revealed a more severe requirement of Abf1 than Fhl1 binding sites for RPG transcription. In the case of RPS22B an unusual Tbf1 binding site promoted both RPS22B and intron-hosted SNR44 expression. Abf1-RPG down-regulation upon TOR pathway inhibition was much attenuated at defective mutant promoters unable to bind Abf1. TORC1 inactivation caused the expected reduction of Ifh1 occupancy at RPS22B and RPL3 promoters, but unexpectedly it entailed largely increased Abf1 association with Abf1-RPG promoters. We present evidence that Abf1 recruitment upon nutritional stress, also observed for representative ribosome biogenesis genes, favours RPG transcriptional rescue upon nutrient replenishment, thus pointing to nutrient-regulated Abf1 dynamics at promoters as a novel mechanism in ribosome biogenesis control. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  15. Mouse alpha1(I)-collagen promoter is the best known promoter to drive efficient Cre recombinase expression in osteoblast.

    PubMed

    Dacquin, Romain; Starbuck, Michael; Schinke, Thorsten; Karsenty, Gérard

    2002-06-01

    Cell- and time-specific gene inactivation should enhance our knowledge of bone biology. Implementation of this technique requires construction of transgenic mouse lines expressing Cre recombinase in osteoblasts, the bone forming cell. We tested several promoter fragments for their ability to drive efficient Cre expression in osteoblasts. In the first mouse transgenic line, the Cre gene was placed under the control of the 2.3-kb proximal fragment of the alpha1(I)-collagen promoter, which is expressed at high levels in osteoblasts throughout their differentiation. Transgenic mice expressing this transgene in bone were bred with the ROSA26 reporter (R26R) strain in which the ROSA26 locus is targeted with a conditional LacZ reporter cassette. In R26R mice, Cre expression and subsequent Cre-mediated recombination lead to expression of the LacZ reporter gene, an event that can be monitored by LacZ staining. LacZ staining was detected in virtually all osteoblasts of alpha1(I)-Cre;R26R mice indicating that homologous recombination occurred in these cells. No other cell type stained blue. In the second line studied, the 1.3-kb fragment of osteocalcin gene 2 (OG2) promoter, which is active in differentiated osteoblasts, was used to drive Cre expression. OG2-Cre mice expressed Cre specifically in bone. However, cross of OG2-Cre mice with R26R mice did not lead to any detectable LacZ staining in osteoblasts. Lastly, we tested a more active artificial promoter derived from the OG2 promoter. The artificial OG2-Cre transgene was expressed by reverse transcriptase-polymerase chain reaction in cartilage and bone samples. After cross of the artificial OG2-Cre mice with R26R mice, we detected a LacZ staining in articular chondrocytes but not in osteoblasts. Our data suggest that the only promoter able to drive Cre expression at a level sufficient to induce recombination in osteoblasts is the alpha1(I)-collagen promoter. Copyright 2002 Wiley-Liss, Inc.

  16. Mit1 Transcription Factor Mediates Methanol Signaling and Regulates the Alcohol Oxidase 1 (AOX1) Promoter in Pichia pastoris.

    PubMed

    Wang, Xiaolong; Wang, Qi; Wang, Jinjia; Bai, Peng; Shi, Lei; Shen, Wei; Zhou, Mian; Zhou, Xiangshan; Zhang, Yuanxing; Cai, Menghao

    2016-03-18

    The alcohol oxidase 1 (AOX1) promoter (P AOX1) of Pichia pastoris is the most powerful and commonly used promoter for driving protein expression. However, mechanisms regulating its transcriptional activity are unclear. Here, we identified a Zn(II)2Cys6-type methanol-induced transcription factor 1 (Mit1) and elucidated its roles in regulating PAOX1 activity in response to glycerol and methanol. Mit1 regulated the expression of many genes involved in methanol utilization pathway, including AOX1, but did not participate in peroxisome proliferation and transportation of peroxisomal proteins during methanol metabolism. Structural analysis of Mit1 by performing domain deletions confirmed its specific and critical role in the strict repression of P AOX1 in glycerol medium. Importantly, Mit1, Mxr1, and Prm1, which positively regulated P AOX1 in response to methanol, were bound to P AOX1 at different sites and did not interact with each other. However, these factors cooperatively activated P AOX1 through a cascade. Mxr1 mainly functioned during carbon derepression, whereas Mit1 and Prm1 functioned during methanol induction, with Prm1 transmitting methanol signal to Mit1 by binding to the MIT1 promoter (P MIT1), thus increasingly expressing Mit1 and subsequently activating P AOX1. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  17. Characterization and functional analysis of the Paralichthys olivaceus prdm1 gene promoter.

    PubMed

    Li, Peizhen; Wang, Bo; Cao, Dandan; Liu, Yuezhong; Zhang, Quanqi; Wang, Xubo

    2017-10-01

    PR domain containing protein 1 (Prdm1) is a transcriptional repressor identified in various species and plays multiple important roles in immune response and embryonic development. However, little is known about the transcriptional regulation of the prdm1 gene. This study aims to characterize the promoter of Paralichthys olivaceus prdm1 (Po-prdm1) gene and determine the regulatory mechanism of Po-prdm1 expression. A 2000bp-long 5'-flanking region (translation initiation site designated as +1) of the Po-prdm1 gene was isolated and characterized. The regulatory elements in this fragment were then investigated and many putative transcription factor (TF) binding sites involved in immunity and multiple tissue development were identified. A 5'-deletion analysis was then conducted, and the ability of the deletion mutants to promote luciferase and green fluorescent protein (GFP) expression in a flounder gill cell line was examined. The results revealed that the minimal promoter is located in the region between -446 and -13bp, and the region between -1415 and -13bp enhanced the promoter activity. Site-directed mutation analysis was subsequently performed on the putative regulatory elements sites, and the results indicated that FOXP1, MSX and BCL6 binding sites play negative functional roles in the regulation of the Po-prdm1 expression in FG cells. In vivo analysis demonstrated that a GFP reporter gene containing 1.4kb-long promoter fragment (-1415/-13) was expressed in the head and trunk muscle fibres of transient transgenic zebrafish embryos. Our study provided the basic information for the exploration of Po-prdm1 regulation and expression. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Prognostic value of MLH1 promoter methylation in male patients with esophageal squamous cell carcinoma.

    PubMed

    Wu, Dongping; Chen, Xiaoying; Xu, Yan; Wang, Haiyong; Yu, Guangmao; Jiang, Luping; Hong, Qingxiao; Duan, Shiwei

    2017-04-01

    The DNA mismatch repair (MMR) gene MutL homolog 1 ( MLH1 ) is critical for the maintenance of genomic integrity. Methylation of the MLH1 gene promoter was identified as a prognostic marker for numerous types of cancer including glioblastoma, colorectal, ovarian and gastric cancer. The present study aimed to determine whether MLH1 promoter methylation was associated with survival in male patients with esophageal squamous cell carcinoma (ESCC). Formalin-fixed, paraffin-embedded ESCC tissues were collected from 87 male patients. MLH1 promoter methylation was assessed using the methylation-specific polymerase chain reaction approach. Kaplan-Meier survival curves and log-rank tests were used to evaluate the association between MLH1 promoter methylation and overall survival (OS) in patients with ESCC. Cox regression analysis was used to obtain crude and multivariate hazard ratios (HR), and 95% confidence intervals (CI). The present study revealed that MLH1 promoter methylation was observed in 53/87 (60.9%) of male patients with ESCC. Kaplan-Meier survival analysis demonstrated that MLH1 promoter hypermethylation was significantly associated with poorer prognosis in patients with ESCC (P=0.048). Multivariate survival analysis revealed that MLH1 promoter hypermethylation was an independent predictor of poor OS in male patients with ESCC (HR=1.716; 95% CI=1.008-2.921). Therefore, MLH1 promoter hypermethylation may be a predictor of prognosis in male patients with ESCC.

  19. Network Commercials Promote Legal Drugs: Outnumber Anti-Drug PSA's 45-to-1.

    ERIC Educational Resources Information Center

    Fedler, Fred; And Others

    1994-01-01

    During the week of September 16-20, 1990, commercials promoting drugs and alcohol outnumbered the networks' news stories, documentaries, and public service announcements (PSAs) about illegal drugs by a ratio of almost 39 to 1. Considering the commercials alone, promotion of drugs and alcohol outnumbered the antidrug promotions by a ratio of almost…

  20. Analysis of tissue-specific region in sericin 1 gene promoter of Bombyx mori

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu Yan; Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031; Yu Lian

    The gene encoding sericin 1 (Ser1) of silkworm (Bombyx mori) is specifically expressed in the middle silk gland cells. To identify element involved in this transcription-dependent spatial restriction, truncation of the 5' terminal from the sericin 1 (Ser1) promoter is studied in vivo. A 209 bp DNA sequence upstream of the transcriptional start site (-586 to -378) is found to be responsible for promoting tissue-specific transcription. Analysis of this 209 bp region by overlapping deletion studies showed that a 25 bp region (-500 to -476) suppresses the ectopic expression of the Ser1 promoter. An unknown factor abundant in fat bodymore » nuclear extracts is shown to bind to this 25 bp fragment. These results suggest that this 25 bp region and the unknown factor are necessary for determining the tissue-specificity of the Ser1 promoter.« less

  1. Regulation of monocarboxylate transporter 1 (MCT1) promoter by butyrate in human intestinal epithelial cells: involvement of NF-kappaB pathway.

    PubMed

    Borthakur, Alip; Saksena, Seema; Gill, Ravinder K; Alrefai, Waddah A; Ramaswamy, Krishnamurthy; Dudeja, Pradeep K

    2008-04-01

    Butyrate, a short chain fatty acid (SCFA) produced by bacterial fermentation of undigested carbohydrates in the colon, constitutes the major fuel for colonocytes. We have earlier shown the role of apically localized monocarboxylate transporter isoform 1 (MCT1) in transport of butyrate into human colonic Caco-2 cells. In an effort to study the regulation of MCT1 gene, we and others have cloned the promoter region of the MCT1 gene and identified cis elements for key transcription factors. A previous study has shown up-regulation of MCT1 expression, and activity by butyrate in AA/C1 human colonic epithelial cells, however, the detailed mechanisms of this up-regulation are not known. In this study, we demonstrate that butyrate, a substrate for MCT1, stimulates MCT1 promoter activity in Caco-2 cells. This effect was dose dependent and specific to butyrate as other predominant SCFAs, acetate, and propionate, were ineffective. Utilizing progressive deletion constructs of the MCT1 promoter, we showed that the putative butyrate responsive elements are in the -229/+91 region of the promoter. Butyrate stimulation of the MCT1 promoter was found to be independent of PKC, PKA, and tyrosine kinases. However, specific inhibitors of the NF-kappaB pathway, lactacystein (LC), and caffeic acid phenyl ester (CAPE) significantly reduced the MCT1 promoter stimulation by butyrate. Also, butyrate directly stimulated NF-kappaB-dependent luciferase reporter activity. Histone deacetylase (HDAC) inhibitor trichostatin A (TSA) also stimulated MCT1 promoter activity, however, unlike butyrate, this stimulation was unaltered by the NF-kappaB inhibitors. Further, the combined effect of butyrate, and TSA on MCT1 promoter activity was additive, indicating that their mechanisms of action were independent. Our results demonstrate the involvement of NF-kappaB pathway in the regulation of MCT1 promoter activity by butyrate. 2007 Wiley-Liss, Inc.

  2. Mutant IDH1 Promotes Glioma Formation In Vivo.

    PubMed

    Philip, Beatrice; Yu, Diana X; Silvis, Mark R; Shin, Clifford H; Robinson, James P; Robinson, Gemma L; Welker, Adam E; Angel, Stephanie N; Tripp, Sheryl R; Sonnen, Joshua A; VanBrocklin, Matthew W; Gibbons, Richard J; Looper, Ryan E; Colman, Howard; Holmen, Sheri L

    2018-05-01

    Isocitrate dehydrogenase 1 (IDH1) is the most commonly mutated gene in grade II-III glioma and secondary glioblastoma (GBM). A causal role for IDH1 R132H in gliomagenesis has been proposed, but functional validation in vivo has not been demonstrated. In this study, we assessed the role of IDH1 R132H in glioma development in the context of clinically relevant cooperating genetic alterations in vitro and in vivo. Immortal astrocytes expressing IDH1 R132H exhibited elevated (R)-2-hydroxyglutarate levels, reduced NADPH, increased proliferation, and anchorage-independent growth. Although not sufficient on its own, IDH1 R132H cooperated with PDGFA and loss of Cdkn2a, Atrx, and Pten to promote glioma development in vivo. These tumors resembled proneural human mutant IDH1 GBM genetically, histologically, and functionally. Our findings support the hypothesis that IDH1 R132H promotes glioma development. This model enhances our understanding of the biology of IDH1 R132H -driven gliomas and facilitates testing of therapeutic strategies designed to combat this deadly disease. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

  3. HIV-1 Tat protein promotes formation of more-processive elongation complexes.

    PubMed Central

    Marciniak, R A; Sharp, P A

    1991-01-01

    The Tat protein of HIV-1 trans-activates transcription in vitro in a cell-free extract of HeLa nuclei. Quantitative analysis of the efficiency of elongation revealed that a majority of the elongation complexes generated by the HIV-1 promoter were not highly processive and terminated within the first 500 nucleotides. Tat trans-activation of transcription from the HIV-1 promoter resulted from an increase in processive character of the elongation complexes. More specifically, the analysis suggests that there exist two classes of elongation complexes initiating from the HIV promoter: a less-processive form and a more-processive form. Addition of purified Tat protein was found to increase the abundance of the more-processive class of elongation complex. The purine nucleoside analog, 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole (DRB) inhibits transcription in this reaction by decreasing the efficiency of elongation. Surprisingly, stimulation of transcription elongation by Tat was preferentially inhibited by the addition of DRB. Images PMID:1756726

  4. RACK1-mediated translation control promotes liver fibrogenesis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Min; Peng, Peike; Wang, Jiajun

    Activation of quiescent hepatic stellate cells (HSCs) is the central event of liver fibrosis. The translational machinery is an optimized molecular network that affects cellular homoeostasis and diseases, whereas the role of protein translation in HSCs activation and liver fibrosis is little defined. Our previous report suggests that up-regulation of receptor for activated C-kinase 1(RACK1) in HSCs is critical for liver fibrogenesis. In this study, we found that RACK1 promoted macrophage conditioned medium (MCM)-induced assembly of eIF4F and phosphorylation of eIF4E in primary HSCs. RACK1 enhanced the translation and expression of pro-fibrogenic factors collagen 1α1, snail and cyclin E1 inducedmore » by MCM. Administration of PP242 or knock-down of eIF4E suppressed RACK1-stimulated collagen 1α1 production, proliferation and migration in primary HSCs. In addition, depletion of eIF4E attenuated thioacetamide (TAA)-induced liver fibrosis in vivo. Our data suggest that RACK1-mediated stimulation of cap-dependent translation plays crucial roles in HSCs activation and liver fibrogenesis, and targeting translation initiation could be a promising strategy for the treatment of liver fibrosis. - Highlights: • RACK1 induces the assembly of eIF4F and phosphorylation of eIF4E in primary HSCs. • RACK1 stimulates the translation of collagen 1α1, snail and cyclin E1 in HSCs. • RACK1 promotes HSCs activation via cap-mediated translation. • Depletion of eIF4E suppresses liver fibrogenesis in vivo.« less

  5. DELLA genes restrict inflorescence meristem function independently of plant height.

    PubMed

    Serrano-Mislata, Antonio; Bencivenga, Stefano; Bush, Max; Schiessl, Katharina; Boden, Scott; Sablowski, Robert

    2017-09-01

    DELLA proteins associate with transcription factors to control plant growth in response to gibberellin 1 . Semi-dwarf DELLA mutants with improved harvest index and decreased lodging greatly improved global food security during the 'green revolution' in the 1960-1970s 2 . However, DELLA mutants are pleiotropic and the developmental basis for their effects on plant architecture remains poorly understood. Here, we show that DELLA proteins have genetically separable roles in controlling stem growth and the size of the inflorescence meristem, where flowers initiate. Quantitative three-dimensional image analysis, combined with a genome-wide screen for DELLA-bound loci in the inflorescence tip, revealed that DELLAs limit meristem size in Arabidopsis by directly upregulating the cell-cycle inhibitor KRP2 in the underlying rib meristem, without affecting the canonical WUSCHEL-CLAVATA meristem size regulators 3 . Mutation of KRP2 in a DELLA semi-dwarf background restored meristem size, but not stem growth, and accelerated flower production. In barley, secondary mutations in the DELLA gain-of-function mutant Sln1d 4 also uncoupled meristem and inflorescence size from plant height. Our work reveals an unexpected and conserved role for DELLA genes in controlling shoot meristem function and suggests how dissection of pleiotropic DELLA functions could unlock further yield gains in semi-dwarf mutants.

  6. Transcription factor EGR1 directs tendon differentiation and promotes tendon repair

    PubMed Central

    Guerquin, Marie-Justine; Charvet, Benjamin; Nourissat, Geoffroy; Havis, Emmanuelle; Ronsin, Olivier; Bonnin, Marie-Ange; Ruggiu, Mathilde; Olivera-Martinez, Isabel; Robert, Nicolas; Lu, Yinhui; Kadler, Karl E.; Baumberger, Tristan; Doursounian, Levon; Berenbaum, Francis; Duprez, Delphine

    2013-01-01

    Tendon formation and repair rely on specific combinations of transcription factors, growth factors, and mechanical parameters that regulate the production and spatial organization of type I collagen. Here, we investigated the function of the zinc finger transcription factor EGR1 in tendon formation, healing, and repair using rodent animal models and mesenchymal stem cells (MSCs). Adult tendons of Egr1–/– mice displayed a deficiency in the expression of tendon genes, including Scx, Col1a1, and Col1a2, and were mechanically weaker compared with their WT littermates. EGR1 was recruited to the Col1a1 and Col2a1 promoters in postnatal mouse tendons in vivo. Egr1 was required for the normal gene response following tendon injury in a mouse model of Achilles tendon healing. Forced Egr1 expression programmed MSCs toward the tendon lineage and promoted the formation of in vitro–engineered tendons from MSCs. The application of EGR1-producing MSCs increased the formation of tendon-like tissues in a rat model of Achilles tendon injury. We provide evidence that the ability of EGR1 to promote tendon differentiation is partially mediated by TGF-β2. This study demonstrates EGR1 involvement in adult tendon formation, healing, and repair and identifies Egr1 as a putative target in tendon repair strategies. PMID:23863709

  7. Air quality in the mountain climate-balneological resort Kislovodsk

    NASA Astrophysics Data System (ADS)

    Chalaya, Elena; Efimenko, Natalia; Povolotckaia, Nina; Senik, Irina; Slepykh, Victor

    2016-04-01

    There has been studied the quality of the surface atmosphere in the mountain climate-balneological resort Kislovodsk (MCBRK) to treat by means of climate and landscape (TCL) of the patients suffering from bronchial asthma (PBA) [1]. 60 children (31 boys and 29 girls at the age of 9-11 years) were examined in the course of 34 days of the resort treatment in MCBRK, PBA (ICD-10 G45,0) in a remission stage. There have been used the data of the long-term bioclimatic monitoring (BCM) that is carried out by PRIC FMBA, aerosol monitoring of IFA RAS, landscape monitoring of SNP in Kislovodsk Resort Park (KRP) as well as the data of medical monitoring, daily testing of meteopathic reactions (MPR), indicators dynamics of bronchial patency, cardiac rhythm, neurovascular reactivity, psychoemotional status of patients. TCL was carried out in the form of walks under the canopy of Betula pendula Roth., Salix f. pendula, acer platanoides globosum, Aesculus hippocastanum L., Phellodendron amurense, Tilia caucasica in KRP daily lasting from 1 till 2 hours. The results of a complex research showed that at TCL in KRP the favourable heat balance had 92% warm relations (TB<600BT/m2 - comfort and weak over comfort); the increased natural aero ionization (∑(N+)+(N-)=1350-1850 ion/cm3 at KUI<0,88); bacteriostatics natural trees 13-58%; the level of the weighed aerosol particles (the size of 500-20000 nanometers) from 1,2 to 3,6 particles/cm3 - (from pure to poorly polluted atmosphere); only 86% of the patients had cases with the increased and high transparency of the atmosphere (0,756-0,849). Under the influence of the course TCL 53(88%) patients had improved indicators of bronchial patency, 58(97%) had signs of increasing qualities of regulatory processes in the organism (vegetative regulation for 14%; neurohumoral regulation for 12%; psychoemotional regulation for 16%; the ability of the organism to adaptation for 17%); 38(63%) patients had vegetative index of Kerde that reached normal

  8. Inhibition of adenovirus replication by the E1A antisense transcript initiated from hsp70 and VA-1 promoters.

    PubMed

    Miroshnichenko, O I; Borisenko, A S; Ponomareva, T I; Tikhonenko, T I

    1990-03-01

    The E1A region of the adenoviral genome, important for initiation of virus infection and activation of other viral genes, was chosen as a target for engineering antisense RNA (asRNA) to inhibit adenovirus 5 (Ad5) replication in COS-1 cell culture in vitro. The hsp70 promoter, taken from the appropriate heat-shock-protein gene of Drosophila melanogaster, and the VA-1 RNA promoter, derived from the Ad5 gene coding for low-molecular-mass VA-1 RNA and recognized by RNA polymerase III were used as regulatory elements of transcription. The two types of recombinant constructs contained E1A fragments of 710 bp (hsp70 constructs) or 380 or 740 bp (VA-1 RNA constructs) in reverse orientation relative to the promoter position, as well as a transcription termination signal, the SV40 ori, and the gene controlling Geneticin (antibiotic G418) resistance (G418R). After selection of transfected COS-1 cells in the presence of G418, a number of stable G418R cell lines were raised which expressed engineered asRNAs. Plating of Ad5 suspensions of known titre on monolayers of transfected COS-1 cells clearly showed strong inhibition of adenovirus replication by asRNAs: 75% with the hsp70 promoter and 90% with the VA-1 RNA promoter.

  9. Sp1 and Sp3 Are the Transcription Activators of Human ek1 Promoter in TSA-Treated Human Colon Carcinoma Cells.

    PubMed

    Kuan, Chee Sian; See Too, Wei Cun; Few, Ling Ling

    2016-01-01

    Ethanolamine kinase (EK) catalyzes the phosphorylation of ethanolamine, the first step in the CDP-ethanolamine pathway for the biosynthesis of phosphatidylethanolamine (PE). Human EK exists as EK1, EK2α and EK2β isoforms, encoded by two separate genes, named ek1 and ek2. EK activity is stimulated by carcinogens and oncogenes, suggesting the involvement of EK in carcinogenesis. Currently, little is known about EK transcriptional regulation by endogenous or exogenous signals, and the ek gene promoter has never been studied. In this report, we mapped the important regulatory regions in the human ek1 promoter. 5' deletion analysis and site-directed mutagenesis identified a Sp site at position (-40/-31) that was essential for the basal transcription of this gene. Treatment of HCT116 cells with trichostatin A (TSA), a histone deacetylase inhibitor, significantly upregulated the ek1 promoter activity through the Sp(-40/-31) site and increased the endogenous expression of ek1. Chromatin immunoprecipitation assay revealed that TSA increased the binding of Sp1, Sp3 and RNA polymerase II to the ek1 promoter in HCT116 cells. The effect of TSA on ek1 promoter activity was cell-line specific as TSA treatment did not affect ek1 promoter activity in HepG2 cells. In conclusion, we showed that Sp1 and Sp3 are not only essential for the basal transcription of the ek1 gene, their accessibility to the target site on the ek1 promoter is regulated by histone protein modification in a cell line dependent manner.

  10. Endometrial Expression of Steroidogenic Factor 1 Promotes Cystic Glandular Morphogenesis

    PubMed Central

    Vasquez, Yasmin M.; Wu, San-Pin; Anderson, Matthew L.; Hawkins, Shannon M.; Creighton, Chad J.; Ray, Madhumita; Tsai, Sophia Y.; Tsai, Ming-Jer; Lydon, John P.

    2016-01-01

    Epigenetic silencing of steroidogenic factor 1 (SF1) is lost in endometriosis, potentially contributing to de novo local steroidogenesis favoring inflammation and growth of ectopic endometrial tissue. In this study, we examine the impact of SF1 expression in the eutopic uterus by a novel mouse model that conditionally expresses SF1 in endometrium. In vivo SF1 expression promoted the development of enlarged endometrial glands and attenuated estrogen and progesterone responsiveness. Endometriosis induction by autotransplantation of uterine tissue to the mesenteric membrane resulted in the increase in size of ectopic lesions from SF1-expressing mice. By integrating the SF1-dependent transcriptome with the whole genome binding profile of SF1, we identified uterine-specific SF1-regulated genes involved in Wingless and Progesterone receptor-Hedgehog-Chicken ovalbumin upstream promoter transcription factor II signaling for gland development and epithelium-stroma interaction, respectively. The present results indicate that SF1 directly contributes to the abnormal uterine gland morphogenesis, an inhibition of steroid hormone signaling and activation of an immune response, in addition to previously postulated estrogen production. PMID:27018534

  11. Two distinct promoters drive transcription of the human D1A dopamine receptor gene.

    PubMed

    Lee, S H; Minowa, M T; Mouradian, M M

    1996-10-11

    The human D1A dopamine receptor gene has a GC-rich, TATA-less promoter located upstream of a small, noncoding exon 1, which is separated from the coding exon 2 by a 116-base pair (bp)-long intron. Serial 3'-deletions of the 5'-noncoding region of this gene, including the intron and 5'-end of exon 2, resulted in 80 and 40% decrease in transcriptional activity of the upstream promoter in two D1A-expressing neuroblastoma cell lines, SK-N-MC and NS20Y, respectively. To investigate the function of this region, the intron and 245 bp at the 5'-end of exon 2 were investigated. Transient expression analyses using various chloramphenicol acetyltransferase constructs showed that the transcriptional activity of the intron is higher than that of the upstream promoter by 12-fold in SK-N-MC cells and by 5.5-fold in NS20Y cells in an orientation-dependent manner, indicating that the D1A intron is a strong promoter. Primer extension and ribonuclease protection assays revealed that transcription driven by the intron promoter is initiated at the junction of intron and exon 2 and at a cluster of nucleotides located 50 bp downstream from this junction. The same transcription start sites are utilized by the chloramphenicol acetyltransferase constructs employed in transfections as well as by the D1A gene expressed within the human caudate. The relative abundance of D1A transcripts originating from the upstream promoter compared with those transcribed from the intron promoter is 1.5-2.9 times in SK-N-MC cells and 2 times in the human caudate. Transcript stability studies in SK-N-MC cells revealed that longer D1A mRNA molecules containing exon 1 are degraded 1.8 times faster than shorter transcripts lacking exon 1. Although gel mobility shift assay could not detect DNA-protein interaction at the D1A intron, competitive co-transfection using the intron as competitor confirmed the presence of trans-acting factors at the intron. These data taken together indicate that the human D1A gene has

  12. Regulation of the syncytin-1 promoter in human astrocytes by multiple sclerosis-related cytokines

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mameli, Giuseppe; Astone, Vito; Khalili, Kamel

    Syncytin-1 has a physiological role during early pregnancy, as mediator of trophoblast fusion into the syncytiotrophoblast layer, hence allowing embryo implantation. In addition, its expression in nerve tissue has been proposed to contribute to the pathogenesis of multiple sclerosis (MS). Syncytin-1 is the env glycoprotein of the ERVWE1 component of the W family of human endogenous retroviruses (HERV), located on chromosome 7q21-22, in a candidate region for genetic susceptibility to MS. The mechanisms of ERVWE1 regulation in nerve tissue remain to be identified. Since there are correlations between some cytokines and MS outcome, we examined the regulation of the syncytin-1more » promoter by MS-related cytokines in human U-87MG astrocytic cells. Using transient transfection assays, we observed that the MS-detrimental cytokines TNF{alpha}, interferon-{gamma}, interleukin-6, and interleukin-1 activate the ERVWE1 promoter, while the MS-protective interferon-{beta} is inhibitory. The effects of cytokines are reduced by the deletion of the cellular enhancer domain of the promoter that contains binding sites for several transcription factors. In particular, we found that TNF{alpha} had the ability to activate the ERVWE1 promoter through an NF-{kappa}B-responsive element located within the enhancer domain of the promoter. Electrophoretic mobility shift and ChIP assays showed that TNF{alpha} enhances the binding of the p65 subunit of NF-{kappa}B, to its cognate site within the promoter. The effect of TNF{alpha} is abolished by siRNA directed against p65. Taken together, these results illustrate a role for p65 in regulating the ERVWE1 promoter and in TNF{alpha}-mediated induction of syncytin-1 in multiple sclerosis.« less

  13. Autocrine CSF-1 and CSF-1 Receptor Co-expression Promotes Renal Cell Carcinoma Growth

    PubMed Central

    Menke, Julia; Kriegsmann, Jörg; Schimanski, Carl Christoph; Schwartz, Melvin M.; Schwarting, Andreas; Kelley, Vicki R.

    2011-01-01

    Renal cell carcinoma is increasing in incidence but the molecular mechanisms regulating its growth remain elusive. Co-expression of the monocytic growth factor CSF-1 and its receptor CSF-1R on renal tubular epithelial cells (TEC) will promote proliferation and anti-apoptosis during regeneration of renal tubules. Here we show that a CSF-1-dependent autocrine pathway is also responsible for the growth of renal cell carcinoma (RCC). CSF-1 and CSF-1R were co-expressed in RCC and TEC proximally adjacent to RCC. CSF-1 engagement of CSF-1R promoted RCC survival and proliferation and reduced apoptosis, in support of the likelihood that CSF-1R effector signals mediate RCC growth. In vivo CSF-1R blockade using a CSF-1R tyrosine kinase inhibitor decreased RCC proliferation and macrophage infiltration in a manner associated with a dramatic reduction in tumor mass. Further mechanistic investigations linked CSF-1 and EGF signaling in RCC. Taken together, our results suggest that budding RCC stimulates the proximal adjacent microenvironment in the kidney to release mediators of CSF-1, CSF-1R and EGF expression in RCC. Further, our findings imply that targeting CSF-1/CSF-1R signaling may be therapeutically effective in RCC. PMID:22052465

  14. The pig CYP2E1 promoter is activated by COUP-TF1 and HNF-1 and is inhibited by androstenone.

    PubMed

    Tambyrajah, Winston S; Doran, Elena; Wood, Jeffrey D; McGivan, John D

    2004-11-15

    Functional analysis of the pig cytochrome P4502E1 (CYP2E1) promoter identified two major activating elements. One corresponded to the hepatic nuclear factor 1 (HNF-1) consensus binding sequence at nucleotides -128/-98 and the other was located in the region -292/-266. The binding of proteins in pig liver nuclear extracts to a synthetic double-stranded oligonucleotide corresponding to this more distal activating sequence was studied by electrophoretic mobility shift assay. The minimum protein binding sequence was identified as TGTTCTGACCTCTGGG. Gel super-shift assays identified the protein binding to this site as chick ovalbumin upstream promoter transcription factor 1 (COUP-TF1). Androstenone inhibited promoter activity in transfection experiments only with constructs which included the COUP-TF1 binding site. Androstenone inhibited COUP-TF1 binding to synthetic oligonucleotides but did not affect HNF-1 binding. The results offer an explanation for the inhibition of CYP2E1 protein expression by androstenone in isolated pig hepatocytes and may be relevant to the low expression of hepatic CYP2E1 in those pigs which accumulate high levels of androstenone in vivo.

  15. PKC-dependent stimulation of the human MCT1 promoter involves transcription factor AP2.

    PubMed

    Saksena, Seema; Dwivedi, Alka; Gill, Ravinder K; Singla, Amika; Alrefai, Waddah A; Malakooti, Jaleh; Ramaswamy, Krishnamurthy; Dudeja, Pradeep K

    2009-02-01

    Monocarboxylate transporter (MCT1) plays an important role in the absorption of short-chain fatty acids (SCFA) such as butyrate in the human colon. Previous studies from our laboratory have demonstrated that phorbol ester, PMA (1 microM, 24 h), upregulates butyrate transport and MCT1 protein expression in human intestinal Caco-2 cells. However, the molecular mechanisms involved in the transcriptional regulation of MCT1 gene expression by PMA in the intestine are not known. In the present study, we showed that PMA (0.1 microM, 24 h) increased the MCT1 promoter activity (-871/+91) by approximately fourfold. A corresponding increase in MCT1 mRNA abundance in response to PMA was also observed. PMA-induced stimulation of MCT1 promoter activity was observed as early as 1 h and persisted until 24 h, suggesting that the effects of PMA are attributable to initial PKC activation. Kinase inhibitor and phosphorylation studies indicated that these effects may be mediated through activation of the atypical PKC-zeta isoform. 5'-deletion studies demonstrated that the MCT1 core promoter region (-229/+91) is the PMA-responsive region. Site-directed mutagenesis studies showed the predominant involvement of potential activator protein 2 (AP2) binding site in the activation of MCT1 promoter activity by PMA. In addition, overexpression of AP2 in Caco-2 cells significantly increased MCT1 promoter activity in a dose-dependent manner. These findings showing the regulation of MCT1 promoter by PKC and AP2 are of significant importance for an understanding of the molecular regulation of SCFA absorption in the human intestine.

  16. Depleting Glycine and Sarcosine in Prostate Cancer Cells as a New Treatment for Advanced Prostate Cancer

    DTIC Science & Technology

    2015-04-01

    expression through a GSK3B-dependent mechanism : a new target for melatonin’s anti-inflammatory action. J Pineal Res. 2013 Nov;55(4):377-87. doi...Myers L, You Z *. Insulin and IGF1 enhance IL- 17-induced chemokine expression through a GSK3B-dependent mechanism : a new target for melatonin’s anti...proliferation and promotion of apoptosis. The molecular mechanism may be that AMPA upregulates the p53 protein level, which subsequently increases p21

  17. 26 CFR 1.162-14 - Expenditures for advertising or promotion of good will.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 2 2010-04-01 2010-04-01 false Expenditures for advertising or promotion of... and Corporations § 1.162-14 Expenditures for advertising or promotion of good will. A corporation... expenditures for advertising or the promotion of good will which it seeks to deduct in the taxable year may not...

  18. Mechanisms of pseudosubstrate inhibition of the anaphase promoting complex by Acm1

    PubMed Central

    Burton, Janet L; Xiong, Yong; Solomon, Mark J

    2011-01-01

    The anaphase promoting complex (APC) is a ubiquitin ligase that promotes the degradation of cell-cycle regulators by the 26S proteasome. Cdc20 and Cdh1 are WD40-containing APC co-activators that bind destruction boxes (DB) and KEN boxes within substrates to recruit them to the APC for ubiquitination. Acm1 is an APCCdh1 inhibitor that utilizes a DB and a KEN box to bind Cdh1 and prevent substrate binding, although Acm1 itself is not a substrate. We investigated what differentiates an APC substrate from an inhibitor. We identified the Acm1 A-motif that interacts with Cdh1 and together with the DB and KEN box is required for APCCdh1 inhibition. A genetic screen identified Cdh1 WD40 domain residues important for Acm1 A-motif interaction and inhibition that appears to reside near Cdh1 residues important for DB recognition. Specific lysine insertion mutations within Acm1 promoted its ubiquitination by APCCdh1 whereas lysine removal from the APC substrate Hsl1 converted it into a potent APCCdh1 inhibitor. These findings suggest that tight Cdh1 binding combined with the inaccessibility of ubiquitinatable lysines contributes to pseudosubstrate inhibition of APCCdh1. PMID:21460798

  19. Hpa1 harpin needs nitroxyl terminus to promote vegetative growth and leaf photosynthesis in Arabidopsis.

    PubMed

    Li, Xiaojie; Han, Liping; Zhao, Yanying; You, Zhenzhen; Dong, Hansong; Zhang, Chunling

    2014-03-01

    Hpa1 is a harpin protein produced by Xanthomonas oryzae, an important bacterial pathogen of rice, and has the growth-promoting activity in plants. To understand the molecular basis for the function of Hpa1, we generated an inactive variant protein, Hpa1 delta NT, by deleting the nitroxyl-terminal region of the Hpa1 sequence and compared Hpa1 delta NT with the full-length protein in terms of the effects on vegetative growth and related physiological responses in Arabidopsis. When Hpa1 was applied to plants, it acted to enhance the vegetative growth but did not affect the floral development. Enhanced plant growth was accompanied by induced expression of growth-promoting genes in plant leaves. The growth-promoting activity of Hpa1 was further correlated with a physiological consequence shown as promoted leaf photosynthesis as a result of facilitated CO2 conduction through leaf stomata and mesophyll cells. On the contrary, plant growth, growth-promoting gene expression, and the physiological consequence changed little in response to the Hpa1 delta NT treatment. These analyses suggest that Hpa1 requires the nitroxyl-terminus to facilitate CO2 transport inside leaf cells and promote leaf photosynthesis and vegetative growth of the plant.

  20. Repression of myoblast proliferation and fibroblast growth factor receptor 1 promoter activity by KLF10 protein.

    PubMed

    Parakati, Rajini; DiMario, Joseph X

    2013-05-10

    FGFR1 gene expression regulates myoblast proliferation and differentiation, and its expression is controlled by Krüppel-like transcription factors. KLF10 interacts with the FGFR1 promoter, repressing its activity and cell proliferation. KLF10 represses FGFR1 promoter activity and thereby myoblast proliferation. A model of transcriptional control of chicken FGFR1 gene regulation during myogenesis is presented. Skeletal muscle development is controlled by regulation of myoblast proliferation and differentiation into muscle fibers. Growth factors such as fibroblast growth factors (FGFs) and their receptors (FGFRs) regulate cell proliferation and differentiation in numerous tissues, including skeletal muscle. Transcriptional regulation of FGFR1 gene expression is developmentally regulated by the Sp1 transcription factor, a member of the Krüppel-like factor (KLF) family of transcriptional regulators. Here, we show that another KLF transcription factor, KLF10, also regulates myoblast proliferation and FGFR1 promoter activity. Expression of KLF10 reduced myoblast proliferation by 86%. KLF10 expression also significantly reduced FGFR1 promoter activity in myoblasts and Sp1-mediated FGFR1 promoter activity in Drosophila SL2 cells. Southwestern blot, electromobility shift, and chromatin immunoprecipitation assays demonstrated that KLF10 bound to the proximal Sp factor binding site of the FGFR1 promoter and reduced Sp1 complex formation with the FGFR1 promoter at that site. These results indicate that KLF10 is an effective repressor of myoblast proliferation and represses FGFR1 promoter activity in these cells via an Sp1 binding site.

  1. Haplotype defined by the MLH1-93G/A polymorphism is associated with MLH1 promoter hypermethylation in sporadic colorectal cancers.

    PubMed

    Miyakura, Yasuyuki; Tahara, Makiko; Lefor, Alan T; Yasuda, Yoshikazu; Sugano, Kokichi

    2014-11-24

    Methylation of the MLH1 promoter region has been suggested to be a major mechanism of gene inactivation in sporadic microsatellite instability-positive (MSI-H) colorectal cancers (CRCs). Recently, single-nucleotide polymorphism (SNP) in the MLH1 promoter region (MLH1-93G/A; rs1800734) has been proposed to be associated with MLH1 promoter methylation, loss of MLH1 protein expression and MSI-H tumors. We examined the association of MLH1-93G/A and six other SNPs surrounding MLH1-93G/A with the methylation status in 210 consecutive sporadic CRCs in Japanese patients. Methylation of the MLH1 promoter region was evaluated by Na-bisulfite polymerase chain reaction (PCR)/single-strand conformation polymorphism (SSCP) analysis. The genotype frequencies of SNPs located in the 54-kb region surrounding the MLH1-93G/A SNP were examined by SSCP analysis. Methylation of the MLH1 promoter region was observed in 28.6% (60/210) of sporadic CRCs. The proportions of MLH1-93G/A genotypes A/A, A/G and G/G were 26% (n=54), 51% (n=108) and 23% (n=48), respectively, and they were significantly associated with the methylation status (p=0.01). There were no significant associations between genotype frequency of the six other SNPs and methylation status. The A-allele of MLH1-93G/A was more common in cases with methylation than the G-allele (p=0.0094), especially in females (p=0.0067). In logistic regression, the A/A genotype of the MLH1-93G/A SNP was shown to be the most significant risk factor for methylation of the MLH1 promoter region (odds ratio 2.82, p=0.003). Furthermore, a haplotype of the A-allele of rs2276807 located -47 kb upstream from the MLH1-93G/A SNP and the A-allele of MLH1-93G/A SNP was significantly associated with MLH1 promoter methylation. These results indicate that individuals, and particularly females, carrying the A-allele at the MLH1-93G/A SNP, especially in association with the A-allele of rs2276807, may harbor an increased risk of methylation of the MLH1 promoter

  2. Preeclampsia is associated with hypermethylation of IGF-1 promoter mediated by DNMT1.

    PubMed

    Ma, Min; Zhou, Qiong-Jie; Xiong, Yu; Li, Bin; Li, Xiao-Tian

    2018-01-01

    Previous studies have demonstrated a dynamic epigenetic regulation of genes expression in placenta trophoblasts and a dynamic imbalance of DNA methylation and hydroxymethylation. Reduced IGF-1 has been observed in preeclampsia. This study was to investigate the interactive roles between IGF-1 and the global DNA methylation/hydroxymethylation, and the status of DNA methylation/hydroxymethylation and associated enzymes such as DNMTs and TETs in peeeclamptic placentas and hypoxic trophoblasts. It was found that IGF-1 was decreased in preeclamptic placentas and hypoxic trophoblasts when compared to the control group using immunohistochemisty, western blot, qRT-PCR and ELISA. Pyrophosphate sequencing showed IGF-1 promoter was significantly hypermethylated in preeclamptic placentas, which was responsible for reduced IGF-1 expression. Preeclamptic placentas and hypoxic trophoblasts were hypermethylated and hypohydroxymethylated accompanied by remarkably higher 5mC, DNMT1 and DNMT3b, and lower DNMT3a, 5hmC, TET1, TET2 and TET3 detected by immunohistochemisty, western blot, qRT-PCR and ELISA. Pearson's correlation confirmed a statistically significant negative correlation between IGF-1 and DNMT1. Furthermore, both treatment with 5-Aza-dc and DNMT1-siRNA significantly increased the expression of IGF-1 in HTR8 cells, indicating the potential mechanism of DNMT1-mediated DNA methylation in IGF-1 regulation. However, IGF-1 didn't change DNA methylation or hydroxymethylation. These findings suggest that preeclampsia is associated with hypermethylation of IGF-1 promoter mediated by DNMT1 and provide new insights into the diagnosis and treatment of preeclampsia.

  3. Preeclampsia is associated with hypermethylation of IGF-1 promoter mediated by DNMT1

    PubMed Central

    Ma, Min; Zhou, Qiong-Jie; Xiong, Yu; Li, Bin; Li, Xiao-Tian

    2018-01-01

    Previous studies have demonstrated a dynamic epigenetic regulation of genes expression in placenta trophoblasts and a dynamic imbalance of DNA methylation and hydroxymethylation. Reduced IGF-1 has been observed in preeclampsia. This study was to investigate the interactive roles between IGF-1 and the global DNA methylation/hydroxymethylation, and the status of DNA methylation/hydroxymethylation and associated enzymes such as DNMTs and TETs in peeeclamptic placentas and hypoxic trophoblasts. It was found that IGF-1 was decreased in preeclamptic placentas and hypoxic trophoblasts when compared to the control group using immunohistochemisty, western blot, qRT-PCR and ELISA. Pyrophosphate sequencing showed IGF-1 promoter was significantly hypermethylated in preeclamptic placentas, which was responsible for reduced IGF-1 expression. Preeclamptic placentas and hypoxic trophoblasts were hypermethylated and hypohydroxymethylated accompanied by remarkably higher 5mC, DNMT1 and DNMT3b, and lower DNMT3a, 5hmC, TET1, TET2 and TET3 detected by immunohistochemisty, western blot, qRT-PCR and ELISA. Pearson’s correlation confirmed a statistically significant negative correlation between IGF-1 and DNMT1. Furthermore, both treatment with 5-Aza-dc and DNMT1-siRNA significantly increased the expression of IGF-1 in HTR8 cells, indicating the potential mechanism of DNMT1-mediated DNA methylation in IGF-1 regulation. However, IGF-1 didn’t change DNA methylation or hydroxymethylation. These findings suggest that preeclampsia is associated with hypermethylation of IGF-1 promoter mediated by DNMT1 and provide new insights into the diagnosis and treatment of preeclampsia. PMID:29422991

  4. DDB1-Mediated CRY1 Degradation Promotes FOXO1-Driven Gluconeogenesis in Liver.

    PubMed

    Tong, Xin; Zhang, Deqiang; Charney, Nicholas; Jin, Ethan; VanDommelen, Kyle; Stamper, Kenneth; Gupta, Neil; Saldate, Johnny; Yin, Lei

    2017-10-01

    Targeted protein degradation through ubiquitination is an important step in the regulation of glucose metabolism. Here, we present evidence that the DDB1-CUL4A ubiquitin E3 ligase functions as a novel metabolic regulator that promotes FOXO1-driven hepatic gluconeogenesis. In vivo, hepatocyte-specific Ddb1 deletion leads to impaired hepatic gluconeogenesis in the mouse liver but protects mice from high-fat diet-induced hyperglycemia. Lack of Ddb1 downregulates FOXO1 protein expression and impairs FOXO1-driven gluconeogenic response. Mechanistically, we discovered that DDB1 enhances FOXO1 protein stability via degrading the circadian protein cryptochrome 1 (CRY1), a known target of DDB1 E3 ligase. In the Cry1 depletion condition, insulin fails to reduce the nuclear FOXO1 abundance and suppress gluconeogenic gene expression. Chronic depletion of Cry1 in the mouse liver not only increases FOXO1 protein but also enhances hepatic gluconeogenesis. Thus, we have identified the DDB1-mediated CRY1 degradation as an important target of insulin action on glucose homeostasis. © 2017 by the American Diabetes Association.

  5. RXRα and LXR activate two promoters in placenta- and tumor-specific expression of PLAC1

    PubMed Central

    Chen, Yaohui; Moradin, Adi; Schlessinger, David; Nagaraja, Ramaiah

    2011-01-01

    PLAC1 expression, first characterized as restricted to developing placenta among normal tissues, is also found in a wide range of tumors and transformed cell lines. To understand the basis for its unusual expression profile, we have analyzed the gene structure and its mode of transcription. We find that the gene has a hitherto unique feature, with two promoters, P1 and P2, separated by 105 kb. P2 has been described before. Here we define P1 and show that it and P2 are activated by RXRα in conjunction with LXRα or LXRβ. In placenta, P2 is the preferred promoter, whereas various tumor cell lines tend to express predominantly either one or the other promoter. Furthermore, when each promoter is fused to a luciferase reporter gene and transfected into cancer cell lines, the promoter corresponding to the more active endogenous promoter is preferentially transcribed. Joint expression of activating nuclear receptors can partially account for the restricted expression of PLAC1 in placenta, and may be co-opted for preferential P1 or P2 PLAC1 expression in various tumor cells. PMID:21937108

  6. MLH1 Promoter Methylation Frequency in Colorectal Cancer Patients and Related Clinicopathological and Molecular Features

    PubMed Central

    Li, Xia; Yao, Xiaoping; Wang, Yibaina; Hu, Fulan; Wang, Fan; Jiang, Liying; Liu, Yupeng; Wang, Da; Sun, Guizhi; Zhao, Yashuang

    2013-01-01

    Purpose To describe the frequency of MLH1 promoter methylation in colorectal cancer (CRC); to explore the associations between MLH1 promoter methylation and clinicopathological and molecular factors using a systematic review and meta-analysis. Methods A literature search of the PubMed and Embase databases was conducted to identify relevant articles published up to September 7, 2012 that described the frequency of MLH1 promoter methylation or its associations with clinicopathological and molecular factors in CRC. The pooled frequency, odds ratio (OR) and 95% confidence intervals (95% CI) were calculated. Results The pooled frequency of MLH1 promoter methylation in unselected CRC was 20.3% (95% CI: 16.8–24.1%). They were 18.7% (95% CI: 14.7–23.6%) and 16.4% (95% CI: 11.9–22.0%) in sporadic and Lynch syndrome (LS) CRC, respectively. Significant associations were observed between MLH1 promoter methylation and gender (pooled OR = 1.641, 95% CI: 1.215–2.215; P = 0.001), tumor location (pooled OR = 3.804, 95% CI: 2.715–5.329; P<0.001), tumor differentiation (pooled OR = 2.131, 95% CI: 1.464–3.102; P<0.001), MSI (OR: 27.096, 95% CI: 13.717–53.526; P<0.001). Significant associations were also observed between MLH1 promoter methylation and MLH1 protein expression, BRAF mutation (OR = 14.919 (95% CI: 6.427–34.631; P<0.001) and 9.419 (95% CI: 2.613–33.953; P = 0.001), respectively). Conclusion The frequency of MLH1 promoter methylation in unselected CRC was 20.3%. They were 18.7% in sporadic CRC and 16.4% in LS CRC, respectively. MLH1 promoter methylation may be significantly associated with gender, tumor location, tumor differentiation, MSI, MLH1 protein expression, and BRAF mutation. PMID:23555617

  7. Fank1 and Jazf1 promote multiciliated cell differentiation in the mouse airway epithelium

    PubMed Central

    Johnson, Jo-Anne; Watson, Julie K.

    2018-01-01

    ABSTRACT The airways are lined by secretory and multiciliated cells which function together to remove particles and debris from the respiratory tract. The transcriptome of multiciliated cells has been extensively studied, but the function of many of the genes identified is unknown. We have established an assay to test the ability of over-expressed transcripts to promote multiciliated cell differentiation in mouse embryonic tracheal explants. Overexpression data indicated that Fibronectin type 3 and ankyrin repeat domains 1 (Fank1) and JAZF zinc finger 1 (Jazf1) promoted multiciliated cell differentiation alone, and cooperatively with the canonical multiciliated cell transcription factor Foxj1. Moreover, knock-down of Fank1 or Jazf1 in adult mouse airway epithelial cultures demonstrated that these factors are both required for ciliated cell differentiation in vitro. This analysis identifies Fank1 and Jazf1 as novel regulators of multiciliated cell differentiation. Moreover, we show that they are likely to function downstream of IL6 signalling and upstream of Foxj1 activity in the process of ciliated cell differentiation. In addition, our in vitro explant assay provides a convenient method for preliminary investigation of over-expression phenotypes in the developing mouse airways. This article has an associated First Person interview with the first author of the paper. PMID:29661797

  8. WIND1 Promotes Shoot Regeneration through Transcriptional Activation of ENHANCER OF SHOOT REGENERATION1 in Arabidopsis[OPEN

    PubMed Central

    Ohnuma, Mariko; Kurata, Tetsuya; Nakata, Masaru; Ohme-Takagi, Masaru

    2017-01-01

    Many plant species display remarkable developmental plasticity and regenerate new organs after injury. Local signals produced by wounding are thought to trigger organ regeneration but molecular mechanisms underlying this control remain largely unknown. We previously identified an AP2/ERF transcription factor WOUND INDUCED DEDIFFERENTIATION1 (WIND1) as a central regulator of wound-induced cellular reprogramming in plants. In this study, we demonstrate that WIND1 promotes callus formation and shoot regeneration by upregulating the expression of the ENHANCER OF SHOOT REGENERATION1 (ESR1) gene, which encodes another AP2/ERF transcription factor in Arabidopsis thaliana. The esr1 mutants are defective in callus formation and shoot regeneration; conversely, its overexpression promotes both of these processes, indicating that ESR1 functions as a critical driver of cellular reprogramming. Our data show that WIND1 directly binds the vascular system-specific and wound-responsive cis-element-like motifs within the ESR1 promoter and activates its expression. The expression of ESR1 is strongly reduced in WIND1-SRDX dominant repressors, and ectopic overexpression of ESR1 bypasses defects in callus formation and shoot regeneration in WIND1-SRDX plants, supporting the notion that ESR1 acts downstream of WIND1. Together, our findings uncover a key molecular pathway that links wound signaling to shoot regeneration in plants. PMID:28011694

  9. Promotion of Preventive Measures in Public Nursery Schools: Lessons From the H1N1 Pandemic.

    PubMed

    Michail, Koralia A; Ioannidou, Christina; Galanis, Petros; Tsoumakas, Kostantinos; Pavlopoulou, Ioanna D

    2017-09-01

    Nursery schools serve as reservoirs of transmission of infectious diseases, and teachers should be able to implement and monitor hygiene measures to prevent them. The aim of the present study was to assess the compliance of nursery school teachers on promoting preventive interventions and to identify associated factors, during the novel H1N1 influenza pandemic. A secondary objective was to evaluate their knowledge and vaccination status regarding the novel virus. A cross-sectional study was performed, with the use of a predesigned anonymous, questionnaire, and distributed to all public nursery teachers of Athens, Greece. General etiquette practices were highly acceptable to over 92% of teachers. Those with longer teaching experience promoted simple preventive measures, such as hand washing and use of hand sanitizer, more often while older children were more likely to familiarize with them. However, teachers presented inadequate knowledge concerning the novel virus and their vaccination rates with the pandemic vaccine were unacceptably low (1.1%). Our study showed that promotion of simple preventive measures is feasible and may contribute to the prevention of outbreaks in nursery schools, although knowledge gaps and fear concerning the pandemic vaccine highlight communication issues.

  10. Loss of Bin1 Promotes the Propagation of Tau Pathology.

    PubMed

    Calafate, Sara; Flavin, William; Verstreken, Patrik; Moechars, Diederik

    2016-10-18

    Tau pathology propagates within synaptically connected neuronal circuits, but the underlying mechanisms are unclear. BIN1-amphiphysin2 is the second most prevalent genetic risk factor for late-onset Alzheimer's disease. In diseased brains, the BIN1-amphiphysin2 neuronal isoform is downregulated. Here, we show that lowering BIN1-amphiphysin2 levels in neurons promotes Tau pathology propagation whereas overexpression of neuronal BIN1-amphiphysin2 inhibits the process in two in vitro models. Increased Tau propagation is caused by increased endocytosis, given our finding that BIN1-amphiphysin2 negatively regulates endocytic flux. Furthermore, blocking endocytosis by inhibiting dynamin also reduces Tau pathology propagation. Using a galectin-3-binding assay, we show that internalized Tau aggregates damage the endosomal membrane, allowing internalized aggregates to leak into the cytoplasm to propagate pathology. Our work indicates that lower BIN1 levels promote the propagation of Tau pathology by efficiently increasing aggregate internalization by endocytosis and endosomal trafficking. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  11. Functionality of promoter microsatellites of arginine vasopressin receptor 1A (AVPR1A): implications for autism.

    PubMed

    Tansey, Katherine E; Hill, Matthew J; Cochrane, Lynne E; Gill, Michael; Anney, Richard Jl; Gallagher, Louise

    2011-03-31

    Arginine vasopressin (AVP) has been hypothesized to play a role in aetiology of autism based on a demonstrated involvement in the regulation of social behaviours. The arginine vasopressin receptor 1A gene (AVPR1A) is widely expressed in the brain and is considered to be a key receptor for regulation of social behaviour. Moreover, genetic variation at AVPR1A has been reported to be associated with autism. Evidence from non-human mammals implicates variation in the 5'-flanking region of AVPR1A in variable gene expression and social behaviour. We examined four tagging single nucleotide polymorphisms (SNPs) (rs3803107, rs1042615, rs3741865, rs11174815) and three microsatellites (RS3, RS1 and AVR) at the AVPR1A gene for association in an autism cohort from Ireland. Two 5'-flanking region polymorphisms in the human AVPR1A, RS3 and RS1, were also tested for their effect on relative promoter activity. The short alleles of RS1 and the SNP rs11174815 show weak association with autism in the Irish population (P = 0.036 and P = 0.008, respectively). Both RS1 and RS3 showed differences in relative promoter activity by length. Shorter repeat alleles of RS1 and RS3 decreased relative promoter activity in the human neuroblastoma cell line SH-SY5Y. These aligning results can be interpreted as a functional route for this association, namely that shorter alleles of RS1 lead to decreased AVPR1A transcription, which may proffer increased susceptibility to the autism phenotype.

  12. Epigenetic modification of the PD-1 (Pdcd1) promoter in effector CD4+ T cells tolerized by peptide immunotherapy

    PubMed Central

    McPherson, Rhoanne C; Konkel, Joanne E; Prendergast, Catriona T; Thomson, John P; Ottaviano, Raffaele; Leech, Melanie D; Kay, Oliver; Zandee, Stephanie E J; Sweenie, Claire H; Wraith, David C; Meehan, Richard R; Drake, Amanda J; Anderton, Stephen M

    2014-01-01

    Clinically effective antigen-based immunotherapy must silence antigen-experienced effector T cells (Teff) driving ongoing immune pathology. Using CD4+ autoimmune Teff cells, we demonstrate that peptide immunotherapy (PIT) is strictly dependent upon sustained T cell expression of the co-inhibitory molecule PD-1. We found high levels of 5-hydroxymethylcytosine (5hmC) at the PD-1 (Pdcd1) promoter of non-tolerant T cells. 5hmC was lost in response to PIT, with DNA hypomethylation of the promoter. We identified dynamic changes in expression of the genes encoding the Ten-Eleven-Translocation (TET) proteins that are associated with the oxidative conversion 5-methylcytosine and 5hmC, during cytosine demethylation. We describe a model whereby promoter demethylation requires the co-incident expression of permissive histone modifications at the Pdcd1 promoter together with TET availability. This combination was only seen in tolerant Teff cells following PIT, but not in Teff that transiently express PD-1. Epigenetic changes at the Pdcd1 locus therefore determine the tolerizing potential of TCR-ligation. DOI: http://dx.doi.org/10.7554/eLife.03416.001 PMID:25546306

  13. Heat Shock Factor 1 Epigenetically Stimulates Glutaminase-1-Dependent mTOR Activation to Promote Colorectal Carcinogenesis.

    PubMed

    Li, Jiaqiu; Song, Ping; Jiang, Tingting; Dai, Dongjun; Wang, Hanying; Sun, Jie; Zhu, Liyuan; Xu, Wenxia; Feng, Lifeng; Shin, Vivian Y; Morrison, Helen; Wang, Xian; Jin, Hongchuan

    2018-04-14

    Heat shock factor 1 (HSF1) generally exhibits its properties under stress conditions. In tumors, HSF1 has a pleiotropic feature in regulating growth, survival, and aggressiveness of cancer cells. In this study, we found HSF1 was increased in colorectal cancer (CRC) and had a positive correlation with shorter disease-free survival (DFS). Knockdown of HSF1 in CRC cells attenuated their growth while inhibiting mTOR activation and glutamine metabolism. HSF1 inhibited the expression of microRNA137 (MIR137), which targeted GLS1 (glutaminase 1), thus stimulating GLS1 protein expression to promote glutaminolysis and mTOR activation. HSF1 bound DNA methyltransferase DNMT3a and recruited it to the promoter of lncRNA MIR137 host gene (MIR137HG), suppressing the generation of primary MIR137. The chemical inhibitor of HSF1 also reduced cell growth, increased apoptosis, and impaired glutamine metabolism in vitro. Moreover, both chemical inhibition and genetic knockout of HSF1 succeeded in increasing MIR137 expression, reducing GLS1 expression, and alleviating colorectal tumorigenesis in azoxymethane (AOM)/dextran sulfate sodium (DSS) mice. In conclusion, HSF1 expression was increased and associated with poor prognosis in CRC. By recruiting DNMT3a to suppress the expression of MIR137 that targets GLS1 mRNA, HSF1 stimulated GLS1-dependent mTOR activation to promote colorectal carcinogenesis. Therefore, targeting HSF1 to attenuate glutaminolysis and mTOR activation could be a promising approach for CRC treatment. Copyright © 2018 The American Society of Gene and Cell Therapy. Published by Elsevier Inc. All rights reserved.

  14. Association and Promoter Analysis of AVPR1A in Finnish Autism Families.

    PubMed

    Kantojärvi, Katri; Oikkonen, Jaana; Kotala, Ilona; Kallela, Jenni; Vanhala, Raija; Onkamo, Päivi; Järvelä, Irma

    2015-10-01

    The arginine vasopressin receptor 1A gene (AVPR1A) is known to affect social communication and has been reported to associate with autism in several studies. Given that the microsatellite RS1 and a few SNPs in the promoter region of the AVPR1A have repeatedly associated with several traits, including autism it is rather surprising that the molecular explanation for these associations has remained unknown, although it has been reported that the allele length of the AVPR1A microsatellites might affect disease risk. Here we carried out an extended association analysis of three microsatellites and 12 tag single nucleotide polymorphisms (SNPs) in and around the AVPR1A gene in 205 Finnish families followed by promoter analysis. FBAT version v2.0.3 was used for family-based genetic association analyses of AVPR1A microsatellites and SNPs. The nearby microsatellite RS1 was found to harbor the best association. Interestingly, there are two potentially relevant transcription factor (TF) binding sites at RS1: for MEF2C and PBX, predicted with the Match algorithm in the TRANSFAC database. Sequence variations changing the affinity of these TFs might partly explain the AVPR1A promoter region associations shown in autism. © 2015 International Society for Autism Research, Wiley Periodicals, Inc.

  15. Epigenetic changes and alternate promoter usage by human colon cancers for expressing DCLK1-isoforms: Clinical Implications

    PubMed Central

    O’Connell, Malaney R.; Sarkar, Shubhashish; Luthra, Gurinder K.; Okugawa, Yoshinaga; Toiyama, Yuji; Gajjar, Aakash H.; Qiu, Suimin; Goel, Ajay; Singh, Pomila

    2015-01-01

    DCLK1 specifically marks colon/pancreatic cancers in mice, and is expressed by human colon adenocarcinomas (hCRCs). Down-regulation of DCLK1 results in loss of cancer-stem-cells (CSCs), and inhibits spheroidal/xenograft growths from hCRC-cells. The 5′-promoter of DCLK1-gene is reportedly hypermethylated in hCRCs, resulting in loss of expression of DCLK1-transcripts, originating from 5′(α)-promoter (termed DCLK1-L, in here). However, in mouse colon-tumors, 5′-promoter of DCLK1-gene remains unchanged, and DCLK1-L, originating from 5′(α)-promoter, is expressed. We hypothesized that elevated levels of DCLK1-protein in hCRC-cells, may be transcribed/translated from an alternate-promoter. Several in silico and molecular biology approaches were used to test our hypothesis. We report for the first time that majority of hCRCs express short-transcripts of DCLK1 (termed DCLK1-S, in here) from an alternate β-promoter in IntronV of the gene, while normal-colons mainly express DCLK1-L from 5′(α)-promoter. We additionally report an important role of β-catenin and TCF4/LEF binding-sites for activating (α)-promoter, while activated NF-κBp65 (bound to NF-κB-cis-element), activates (β)-promoter in cancer-cells. DCLK1-S expression was examined in a cohort of 92 CRC patients; high-expressors had significantly worse overall-survival compared to low-expressors. Our novel findings’ regarding usage of alternate (β)-promoter by hCRCs, suggests that DCLK1-S may represent an important target for preventing/inhibiting colon-cancers, and for eliminating colon-CSCs. PMID:26447334

  16. Vibrational Spectra of Cryogenic Peptide Ions Using H_2 Predissociation Spectroscopy

    NASA Astrophysics Data System (ADS)

    Leavitt, Christopher M.; Wolk, Arron B.; Kamrath, Michael Z.; Garand, Etienne; Johnson, Mark A.; van Stipdonk, Michael J.

    2011-06-01

    H_2 predissociation spectroscopy was used to collect the vibrational spectra of the model protonated peptides, GlyGly, GlySar, SarGly and SarSar (Gly=glycine and Sar=sarcosine). H_2 molecules were condensed onto protonated peptide ions in a quadrupole ion trap cooled to approximately 10 K. The resulting spectra yielded clearly resolved vibrational transitions throughout the mid IR region, 600-4200 Cm-1, with linewidths of approximately 6 Cm-1. Protonation nominally occurred on the amino terminus giving rise to an intramolecular H-bond between the protonated amine and the neighboring amide oxygen. The sarcosine containing peptides incorporate a methyl group onto either the amino group or the amide nitrogen causing the peptide backbone to adopt a different structure, resulting in the shifts in the amide I and II bands and the N-H stretches.

  17. 1,25-Dihydroxyvitamin D3 inhibition of col1a1 promoter expression in calvariae from neonatal transgenic mice

    NASA Technical Reports Server (NTRS)

    Bedalov, A.; Salvatori, R.; Dodig, M.; Kapural, B.; Pavlin, D.; Kream, B. E.; Clark, S. H.; Woody, C. O.; Rowe, D. W.; Lichtler, A. C.

    1998-01-01

    We studied the effect of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) on organ cultures of transgenic mouse calvariae containing segments of the Col1a1 promoter extending to -3518, -2297, -1997, -1794, -1763, and -1719 bp upstream of the transcription start site fused to the chloramphenicol acetyltransferase (CAT) reporter gene. 1,25(OH)2D3 had a dose-dependent inhibitory effect on the expression of the -3518 bp promoter construct (ColCAT3.6), with maximal inhibition of about 50% at 10 nM. This level of inhibition was consistent with the previously observed effect on the endogenous Col1a1 gene in bone cell models. All of the shorter constructs were also inhibited by 10 nM 1,25(OH)2D3, suggesting that the sequences required for 1, 25(OH)2D3 inhibition are downstream of -1719 bp. The inhibitory effect of 1,25(OH)2D3 on transgene mRNA was maintained in the presence of the protein synthesis inhibitor cycloheximide, suggesting that the inhibitory effect on Col1a1 gene transcription does not require de novo protein synthesis. We also examined the in vivo effect of 1,25(OH)2D3 treatment of transgenic mice on ColCAT activity, and found that 48 h treatment caused a dose-dependent inhibition of CAT activity in calvariae comparable to that observed in organ cultures. In conclusion, we demonstrated that 1,25(OH)2D3 inhibits Col1A1 promoter activity in transgenic mouse calvariae, both in vivo and in vitro. The results indicate that there is a 1, 25(OH)2D3 responsive element downstream of -1719 bp. The inhibitory effect does not require new protein synthesis.

  18. Retinoid regulation of the zebrafish cyp26a1 promoter.

    PubMed

    Hu, Ping; Tian, Miao; Bao, Jie; Xing, Guangdong; Gu, Xingxing; Gao, Xiang; Linney, Elwood; Zhao, Qingshun

    2008-12-01

    Cyp26A1 is a major enzyme that controls retinoic acid (RA) homeostasis by metabolizing RA into bio-inactive metabolites. Previous research revealed that the mouse Cyp26A1 promoter has two canonical RA response elements (RAREs) that underlie the regulation of the gene by RA. Analyzing the 2,533-base pairs (2.5 k) genomic sequence upstream of zebrafish cyp26a1 start codon, we report that the two RAREs are conserved in zebrafish cyp26a1 promoter. Mutagenesis demonstrated that the two RAREs work synergistically in RA inducibility of cyp26a1. Fusing the 2.5 k (kilobase pairs) fragment to the enhanced yellow fluorescent protein (eYFP) reporter gene, we have generated two transgenic lines of zebrafish [Tg(cyp26a1:eYFP)]. The transgenic zebrafish display expression patterns similar to that of cyp26a1 gene in vivo. Consistent with the in vitro results, the reporter activity is RA inducible in embryos. Taken together, our results demonstrate that the 2.5 k fragment underlies the regulation of the zebrafish cyp26a1 gene by RA. (c) 2008 Wiley-Liss, Inc.

  19. SAMHD1 Inhibits LINE-1 Retrotransposition by Promoting Stress Granule Formation

    PubMed Central

    Xu, Fengwen; Mei, Shan; Le Duff, Yann; Yin, Lijuan; Pang, Xiaojing; Cen, Shan; Jin, Qi; Liang, Chen; Guo, Fei

    2015-01-01

    The SAM domain and HD domain containing protein 1 (SAMHD1) inhibits retroviruses, DNA viruses and long interspersed element 1 (LINE-1). Given that in dividing cells, SAMHD1 loses its antiviral function yet still potently restricts LINE-1, we propose that, instead of blocking viral DNA synthesis by virtue of its dNTP triphosphohydrolase activity, SAMHD1 may exploit a different mechanism to control LINE-1. Here, we report a new activity of SAMHD1 in promoting cellular stress granule assembly, which correlates with increased phosphorylation of eIF2α and diminished eIF4A/eIF4G interaction. This function of SAMHD1 enhances sequestration of LINE-1 RNP in stress granules and consequent blockade to LINE-1 retrotransposition. In support of this new mechanism of action, depletion of stress granule marker proteins G3BP1 or TIA1 abrogates stress granule formation and overcomes SAMHD1 inhibition of LINE-1. Together, these data reveal a new mechanism for SAMHD1 to control LINE-1 by activating cellular stress granule pathway. PMID:26134849

  20. Identification of Staphylococcal Nuclease Domain-containing 1 (SND1) as a Metadherin-interacting Protein with Metastasis-promoting Functions*

    PubMed Central

    Blanco, Mario Andres; Alečković, Maša; Hua, Yuling; Li, Tuo; Wei, Yong; Xu, Zhen; Cristea, Ileana M.; Kang, Yibin

    2011-01-01

    Metastasis is the deadliest and most poorly understood feature of malignant diseases. Recent work has shown that Metadherin (MTDH) is overexpressed in over 40% of breast cancer patients and promotes metastasis and chemoresistance in experimental models of breast cancer progression. Here we applied mass spectrometry-based screen to identify staphylococcal nuclease domain-containing 1 (SND1) as a candidate MTDH-interacting protein. After confirming the interaction between SND1 and MTDH, we tested the role of SND1 in breast cancer and found that it strongly promotes lung metastasis. SND1 was further shown to promote resistance to apoptosis and to regulate the expression of genes associated with metastasis and chemoresistance. Analyses of breast cancer clinical microarray data indicated that high expression of SND1 in primary tumors is strongly associated with reduced metastasis-free survival in multiple large scale data sets. Thus, we have uncovered SND1 as a novel MTDH-interacting protein and shown that it is a functionally and clinically significant mediator of metastasis. PMID:21478147

  1. Characterization of the rat RALDH1 promoter. A functional CCAAT and octamer motif are critical for basal promoter activity.

    PubMed

    Guimond, Julie; Devost, Dominic; Brodeur, Helene; Mader, Sylvie; Bhat, Pangala V

    2002-12-12

    Retinal dehydrogenase type 1 (RALDH1) catalyzes the oxidation of retinal to retinoic acid (RA), a metabolite of vitamin A important for embryogenesis and tissue differentiation. Rat RALDH1 is expressed to high levels in developing kidney, and in stomach, intestine epithelia. To understand the mechanisms of the transcriptional regulation of rat RALDH1, we cloned a 1360-base pair (bp) 5'-flanking region of RALDH1 gene. Using luciferase reporter constructs transfected into HEK 293 and LLCPK (kidney-derived) cells, basal promoter activity was associated with sequences between -80 and +43. In this minimal promoter region, TATA and CCAAT cis-acting elements as well as SP1, AP1 and octamer (Oct)-binding sites were present. The CCAAT box and Oct-binding site, located between positions -72 and -68 and -56 and -49, respectively, were shown by deletion analysis and site-directed mutation to be critical for promoter activity. Nuclear extracts from kidney cells contain proteins specifically binding the Oct and CCAAT sequences, resulting in the formation of six complexes, while different patterns of complexes were observed with non-kidney cell extracts. Gel shift assays using either single or double mutations of the Oct and CCAAT sequences as well as super shift assays demonstrated single and double occupancy of these two sites by Oct-1 and CBF-A. In addition, unidentified proteins also bound the Oct motif specifically in the absence of CBF-A binding. These results demonstrate specific involvement of Oct and CCAAT-binding proteins in the regulation of RALDH1 gene.

  2. Physical interaction of the activator protein-1 factors c-Fos and c-Jun with Cbfa1 for collagenase-3 promoter activation

    NASA Technical Reports Server (NTRS)

    D'Alonzo, Richard C.; Selvamurugan, Nagarajan; Karsenty, Gerard; Partridge, Nicola C.

    2002-01-01

    Previously, we determined that the activator protein-1 (AP-1)-binding site and the runt domain (RD)-binding site and their binding proteins, c-Fos.c-Jun and Cbfa, regulate the collagenase-3 promoter in parathyroid hormone-treated and differentiating osteoblasts. Here we show that Cbfa1 and c-Fos.c-Jun appear to cooperatively bind the RD- and AP-1-binding sites and form ternary structures in vitro. Both in vitro and in vivo co-immunoprecipitation and yeast two-hybrid studies further demonstrate interaction between Cbfa1 with c-Fos and c-Jun in the absence of phosphorylation and without binding to DNA. Additionally, only the runt domain of Cbfa1 was required for interaction with c-Jun and c-Fos. In mammalian cells, overexpression of Cbfa1 enhanced c-Jun activation of AP-1-binding site promoter activity, demonstrating functional interaction. Finally, insertion of base pairs that disrupted the helical phasing between the AP-1- and RD-binding sites also inhibited collagenase-3 promoter activation. Thus, we provide direct evidence that Cbfa1 and c-Fos.c-Jun physically interact and cooperatively bind the AP-1- and RD-binding sites in the collagenase-3 promoter. Moreover, the AP-1- and RD-binding sites appear to be organized in a specific required helical arrangement that facilitates transcription factor interaction and enables promoter activation.

  3. Mapping of oxidative stress response elements of the caveolin-1 promoter.

    PubMed

    Bartholomew, Janine N; Galbiati, Ferruccio

    2010-01-01

    According to the "free radical theory" of aging, normal aging occurs as the result of tissue damages inflicted by reactive oxygen species (ROS). ROS are known to induce cellular senescence, and senescent cells are believed to contribute to organismal aging. The molecular mechanisms that mediate the cellular response to oxidants remain to be fully identified. We have shown that oxidative stress induces cellular senescence through activation of the caveolin-1 promoter and upregulation of caveolin-1 protein expression. Here, we describe how reactive oxygen species activate the caveolin-1 promoter and how the signaling may be assayed. These approaches provide insight into the functional role of caveolin-1 and potentially allow the identification of novel ROS-regulated genes that are part of the signaling machinery regulating cellular senescence/aging.

  4. Promoter methylation assay of SASH1 gene in hepatocellular carcinoma.

    PubMed

    Peng, Liu; Wei, He; Liren, Li

    2014-01-01

    To analyse the relationship between the expression of SASH1 and its methylation level in human hepatocellular carcinoma. Expression levels of SASH1 were examined with real-time PCR (RT-PCR) in tissues and cells, and methylation analysis was performed with MassArray. The expression levels of SASH1 were strongly reduced in liver cancer tissues compared with adjacent normal tissues. Quantitative methylation analysis by MassArray revealed different CpG sites in SASH1 promoter shared similar methylation pattern between liver cancer tissues and adjacent normal tissues and the CpG sites of significant difference in methylation level were found as follows: CpG_3, CpG_17, CpG_21.22, CpG_25, CpG_26.27, CpG_28, CpG_34.35.36 and CpG_51.52. Moreover, 5-aza-2'-deoxycytidine treatment of Hep-G2 cell line caused significant elevation of SASH1 mRNA. Based on these data, we propose that increase of DNA methylation degree in the promoter region of SASH1 gene, particularly CpG_26.27 sites, possibly repressed SASH1 expression in liver cancer.

  5. Dynamic interactions between the promoter and terminator regions of the mammalian BRCA1 gene.

    PubMed

    Tan-Wong, Sue Mei; French, Juliet D; Proudfoot, Nicholas J; Brown, Melissa A

    2008-04-01

    The 85-kb breast cancer-associated gene BRCA1 is an established tumor suppressor gene, but its regulation is poorly understood. We demonstrate by gene conformation analysis in both human cell lines and mouse mammary tissue that gene loops are imposed on BRCA1 between the promoter, introns, and terminator region. Significantly, association between the BRCA1 promoter and terminator regions change upon estrogen stimulation and during lactational development. Loop formation is transcription-dependent, suggesting that transcriptional elongation plays an active role in BRCA1 loop formation. We show that the BRCA1 terminator region can suppress estrogen-induced transcription and so may regulate BRCA1 expression. Significantly, BRCA1 promoter and terminator interactions vary in different breast cancer cell lines, indicating that defects in BRCA1 chromatin structure may contribute to dysregulated expression of BRCA1 seen in breast tumors.

  6. The promoter of the cereal VERNALIZATION1 gene is sufficient for transcriptional induction by prolonged cold.

    PubMed

    Alonso-Peral, Maria M; Oliver, Sandra N; Casao, M Cristina; Greenup, Aaron A; Trevaskis, Ben

    2011-01-01

    The VERNALIZATION1 (VRN1) gene of temperate cereals is transcriptionally activated by prolonged cold during winter (vernalization) to promote flowering. To investigate the mechanisms controlling induction of VRN1 by prolonged cold, different regions of the VRN1 gene were fused to the GREEN FLUORESCENT PROTEIN (GFP) reporter and expression of the resulting gene constructs was assayed in transgenic barley (Hordeum vulgare). A 2 kb segment of the promoter of VRN1 was sufficient for GFP expression in the leaves and shoot apex of transgenic barley plants. Fluorescence increased at the shoot apex prior to inflorescence initiation and was subsequently maintained in the developing inflorescence. The promoter was also sufficient for low-temperature induction of GFP expression. A naturally occurring insertion in the proximal promoter, which is associated with elevated VRN1 expression and early flowering in some spring wheats, did not abolish induction of VRN1 transcription by prolonged cold, however. A translational fusion of the promoter and transcribed regions of VRN1 to GFP, VRN1::GFP, was localised to nuclei of cells at the shoot apex of transgenic barley plants. The distribution of VRN1::GFP at the shoot apex was similar to the expression pattern of the VRN1 promoter-GFP reporter gene. Fluorescence from the VRN1::GFP fusion protein increased in the developing leaves after prolonged cold treatment. These observations suggest that the promoter of VRN1 is targeted by mechanisms that trigger vernalization-induced flowering in economically important temperate cereal crops.

  7. Astaxanthin prevents pulmonary fibrosis by promoting myofibroblast apoptosis dependent on Drp1-mediated mitochondrial fission

    PubMed Central

    Zhang, Jinjin; Xu, Pan; Wang, Youlei; Wang, Meirong; Li, Hongbo; Lin, Shengcui; Mao, Cuiping; Wang, Bingsi; Song, Xiaodong; Lv, Changjun

    2015-01-01

    Promotion of myofibroblast apoptosis is a potential therapeutic strategy for pulmonary fibrosis. This study investigated the antifibrotic effect of astaxanthin on the promotion of myofibroblast apoptosis based on dynamin-related protein-1 (Drp1)-mediated mitochondrial fission in vivo and in vitro. Results showed that astaxanthin can inhibit lung parenchymal distortion and collagen deposition, as well as promote myofibroblast apoptosis. Astaxanthin demonstrated pro-apoptotic function in myofibroblasts by contributing to mitochondrial fission, thereby leading to apoptosis by increasing the Drp1 expression and enhancing Drp1 translocation into the mitochondria. Two specific siRNAs were used to demonstrate that Drp1 is necessary to promote astaxanthin-induced mitochondrial fission and apoptosis in myofibroblasts. Drp1-associated genes, such as Bcl-2-associated X protein, cytochrome c, tumour suppressor gene p53 and p53-up-regulated modulator of apoptosis, were highly up-regulated in the astaxanthin group compared with those in the sham group. This study revealed that astaxanthin can prevent pulmonary fibrosis by promoting myofibroblast apoptosis through a Drp1-dependent molecular pathway. Furthermore, astaxanthin provides a potential therapeutic value in pulmonary fibrosis treatment. PMID:26119034

  8. GFRA1 promotes cisplatin-induced chemoresistance in osteosarcoma by inducing autophagy

    PubMed Central

    Kim, Mihwa; Jung, Ji-Yeon; Choi, Seungho; Lee, Hyunseung; Morales, Liza D.; Koh, Jeong-Tae; Kim, Sun Hun; Choi, Yoo-Duk; Choi, Chan; Slaga, Thomas J.; Kim, Won Jae; Kim, Dae Joon

    2017-01-01

    ABSTRACT Recent progress in chemotherapy has significantly increased its efficacy, yet the development of chemoresistance remains a major drawback. In this study, we show that GFRA1/GFRα1 (GDNF family receptor α 1), contributes to cisplatin-induced chemoresistance by regulating autophagy in osteosarcoma. We demonstrate that cisplatin treatment induced GFRA1 expression in human osteosarcoma cells. Induction of GFRA1 expression reduced cisplatin-induced apoptotic cell death and it significantly increased osteosarcoma cell survival via autophagy. GFRA1 regulates AMPK-dependent autophagy by promoting SRC phosphorylation independent of proto-oncogene RET kinase. Cisplatin-resistant osteosarcoma cells showed NFKB1/NFκB-mediated GFRA1 expression. GFRA1 expression promoted tumor formation and growth in mouse xenograft models and inhibition of autophagy in a GFRA1-expressing xenograft mouse model during cisplatin treatment effectively reduced tumor growth and increased survival. In cisplatin-treated patients, treatment period and metastatic status were associated with GFRA1-mediated autophagy. These findings suggest that GFRA1-mediated autophagy is a promising novel target for overcoming cisplatin resistance in osteosarcoma. PMID:27754745

  9. GFRA1 promotes cisplatin-induced chemoresistance in osteosarcoma by inducing autophagy.

    PubMed

    Kim, Mihwa; Jung, Ji-Yeon; Choi, Seungho; Lee, Hyunseung; Morales, Liza D; Koh, Jeong-Tae; Kim, Sun Hun; Choi, Yoo-Duk; Choi, Chan; Slaga, Thomas J; Kim, Won Jae; Kim, Dae Joon

    2017-01-02

    Recent progress in chemotherapy has significantly increased its efficacy, yet the development of chemoresistance remains a major drawback. In this study, we show that GFRA1/GFRα1 (GDNF family receptor α 1), contributes to cisplatin-induced chemoresistance by regulating autophagy in osteosarcoma. We demonstrate that cisplatin treatment induced GFRA1 expression in human osteosarcoma cells. Induction of GFRA1 expression reduced cisplatin-induced apoptotic cell death and it significantly increased osteosarcoma cell survival via autophagy. GFRA1 regulates AMPK-dependent autophagy by promoting SRC phosphorylation independent of proto-oncogene RET kinase. Cisplatin-resistant osteosarcoma cells showed NFKB1/NFκB-mediated GFRA1 expression. GFRA1 expression promoted tumor formation and growth in mouse xenograft models and inhibition of autophagy in a GFRA1-expressing xenograft mouse model during cisplatin treatment effectively reduced tumor growth and increased survival. In cisplatin-treated patients, treatment period and metastatic status were associated with GFRA1-mediated autophagy. These findings suggest that GFRA1-mediated autophagy is a promising novel target for overcoming cisplatin resistance in osteosarcoma.

  10. TIM-1 Promotes Hepatitis C Virus Cell Attachment and Infection.

    PubMed

    Wang, Jing; Qiao, Luhua; Hou, Zhouhua; Luo, Guangxiang

    2017-01-15

    Human TIM and TAM family proteins were recently found to serve as phosphatidylserine (PS) receptors which promote infections by many different viruses, including dengue virus, West Nile virus, Ebola virus, Marburg virus, and Zika virus. In the present study, we provide substantial evidence demonstrating that TIM-1 is important for efficient infection by hepatitis C virus (HCV). The knockdown of TIM-1 expression significantly reduced HCV infection but not HCV RNA replication. Likewise, TIM-1 knockout in Huh-7.5 cells remarkably lowered HCV cell attachment and subsequent HCV infection. More significantly, the impairment of HCV infection in the TIM-1 knockout cells could be restored completely by ectopic expression of TIM-1 but not TIM-3 or TIM-4. Additionally, HCV infection and cell attachment were inhibited by PS but not by phosphatidylcholine (PC), demonstrating that TIM-1-mediated enhancement of HCV infection is PS dependent. The exposure of PS on the HCV envelope was confirmed by immunoprecipitation of HCV particles with a PS-specific monoclonal antibody. Collectively, these findings demonstrate that TIM-1 promotes HCV infection by serving as an attachment receptor for binding to PS exposed on the HCV envelope. TIM family proteins were recently found to enhance infections by many different viruses, including several members of the Flaviviridae family. However, their importance in HCV infection has not previously been examined experimentally. The TIM family proteins include three members in humans: TIM-1, TIM-3, and TIM-4. The findings derived from our studies demonstrate that TIM-1, but not TIM-3 or TIM-4, promotes HCV infection by functioning as an HCV attachment factor. Knockout of the TIM-1 gene resulted in a remarkable reduction of HCV cell attachment and infection. PS-containing liposomes blocked HCV cell attachment and subsequent HCV infection. HCV particles could also be precipitated with a PS-specific monoclonal antibody. These findings suggest that TIM-1

  11. Milk—A Nutrient System of Mammalian Evolution Promoting mTORC1-Dependent Translation

    PubMed Central

    Melnik, Bodo C.

    2015-01-01

    Based on own translational research of the biochemical and hormonal effects of cow’s milk consumption in humans, this review presents milk as a signaling system of mammalian evolution that activates the nutrient-sensitive kinase mechanistic target of rapamycin complex 1 (mTORC1), the pivotal regulator of translation. Milk, a mammary gland-derived secretory product, is required for species-specific gene-nutrient interactions that promote appropriate growth and development of the newborn mammal. This signaling system is highly conserved and tightly controlled by the lactation genome. Milk is sufficient to activate mTORC1, the crucial regulator of protein, lipid, and nucleotide synthesis orchestrating anabolism, cell growth and proliferation. To fulfill its mTORC1-activating function, milk delivers four key metabolic messengers: (1) essential branched-chain amino acids (BCAAs); (2) glutamine; (3) palmitic acid; and (4) bioactive exosomal microRNAs, which in a synergistical fashion promote mTORC1-dependent translation. In all mammals except Neolithic humans, postnatal activation of mTORC1 by milk intake is restricted to the postnatal lactation period. It is of critical concern that persistent hyperactivation of mTORC1 is associated with aging and the development of age-related disorders such as obesity, type 2 diabetes mellitus, cancer, and neurodegenerative diseases. Persistent mTORC1 activation promotes endoplasmic reticulum (ER) stress and drives an aimless quasi-program, which promotes aging and age-related diseases. PMID:26225961

  12. P1 interneurons promote a persistent internal state that enhances inter-male aggression in Drosophila

    PubMed Central

    Hoopfer, Eric D; Jung, Yonil; Inagaki, Hidehiko K; Rubin, Gerald M; Anderson, David J

    2015-01-01

    How brains are hardwired to produce aggressive behavior, and how aggression circuits are related to those that mediate courtship, is not well understood. A large-scale screen for aggression-promoting neurons in Drosophila identified several independent hits that enhanced both inter-male aggression and courtship. Genetic intersections revealed that 8-10 P1 interneurons, previously thought to exclusively control male courtship, were sufficient to promote fighting. Optogenetic experiments indicated that P1 activation could promote aggression at a threshold below that required for wing extension. P1 activation in the absence of wing extension triggered persistent aggression via an internal state that could endure for minutes. High-frequency P1 activation promoted wing extension and suppressed aggression during photostimulation, whereas aggression resumed and wing extension was inhibited following photostimulation offset. Thus, P1 neuron activation promotes a latent, internal state that facilitates aggression and courtship, and controls the overt expression of these social behaviors in a threshold-dependent, inverse manner. DOI: http://dx.doi.org/10.7554/eLife.11346.001 PMID:26714106

  13. The pea END1 promoter drives anther-specific gene expression in different plant species.

    PubMed

    Gómez, María D; Beltrán, José-Pío; Cañas, Luis A

    2004-10-01

    END1 was isolated by an immunosubtractive approach intended to identify specific proteins present in the different pea (Pisum sativum L.) floral organs and the genes encoding them. Following this strategy we obtained a monoclonal antibody (mAbA1) that specifically recognized a 26-kDa protein (END1) only detected in anther tissues. Northern blot assays showed that END1 is expressed specifically in the anther. In situ hybridization and immunolocalization assays corroborated the specific expression of END1 in the epidermis, connective, endothecium and middle layer cells during the different stages of anther development. END1 is the first anther-specific gene isolated from pea. The absence of a practicable pea transformation method together with the fact that no END1 homologue gene exists in Arabidopsis prevented us from carrying out END1 functional studies. However, we designed functional studies with the END1 promoter in different dicot species, as the specific spatial and temporal expression pattern of END1 suggested, among other things, the possibility of using its promoter region for biotechnological applications. Using different constructs to drive the uidA (beta-glucuronidase) gene controlled by the 2.7-kb isolated promoter sequence we have proven that the END1 promoter is fully functional in the anthers of transgenic Arabidopsis thaliana (L.) Heynh., Nicotiana tabacum L. (tobacco) and Lycopersicon esculentum Mill. (tomato) plants. The presence in the -330-bp region of the promoter sequence of three putative CArG boxes also suggests that END1 could be a target gene of MADS-box proteins and that, subsequently, it would be activated by genes controlling floral organ identity.

  14. Methylation Status of the RIZ1 Gene Promoter in Human Glioma Tissues and Cell Lines.

    PubMed

    Zhang, Chenran; Meng, Wei; Wang, Jiajia; Lu, Yicheng; Hu, Guohan; Hu, Liuhua; Ma, Jie

    2017-08-01

    Retinoblastoma protein-interacting zinc-finger gene 1 (RIZ1), a strong tumor suppressor, is silenced in many human cancers. Our previous studies showed that RIZ1 expression was negatively correlated with the grade of glioma and was a key predictor of patient survival. Therefore, RIZ1 could be a potential tumor suppressor during glioma pathogenesis, although the mechanism underlying RIZ1 gene inactivation in gliomas is unknown. We investigated the methylation status of the RIZ1 promoter in human glioma tissues and four glioblastoma (GBM) cell lines, and verified the effect of the methyltransferase inhibitor 5-aza-2-deoxycytidine (5-aza-CdR) on RIZ1 transcription and cell proliferation. Methylation-specific PCR (MSP) was performed to determine RIZ1 promoter methylation in human glioma specimens. The correlation between RIZ1 hypermethylation in tumors and clinicopathological features also was analyzed. 5-Aza-CdR treatment was used to reactivate gene expression silenced by hypermethylation in the U87 glioblastoma cell line, and real-time PCR was then used to measure RIZ1 expression. The ability of 5-aza-CdR to inhibit the proliferation of glioma cell lines whose RIZ1 promoters were hypermethylated was measured by bromodeoxyuridine (BrdU) incorporation. Among 51 human glioma specimens, RIZ1 promoter methylation was detected in 23 cases. Clinicopathological evaluation suggested that RIZ1 hypermethylation was negatively associated with tumor grade and patient age (P < 0.05). Hypermethylation of the RIZ1 promoter was detected in the U87 and U251 cell lines. RIZ1 mRNA expression in U87 cells was upregulated after treatment with 5-aza-Cdr, which correlated with inhibition of cell proliferation in a time- and concentration-dependent manner. Promoter hypermethylation may play an important role in the epigenetic silencing of RIZ1 expression in human glioma tissues and GBM cell lines.

  15. A novel mechanism of skin tumor promotion involving interferon-gamma (IFNγ)/signal transducer and activator of transcription-1 (Stat1) signaling.

    PubMed

    Bozeman, Ronald; Abel, Erika L; Macias, Everardo; Cheng, Tianyi; Beltran, Linda; DiGiovanni, John

    2015-08-01

    The current study was designed to explore the role of signal transducer and activator of transcription 1 (Stat1) during tumor promotion using the mouse skin multistage carcinogenesis model. Topical treatment with both 12-O-tetradecanoylphorbol-13-acetate (TPA) and 3-methyl-1,8-dihydroxy-9-anthrone (chrysarobin or CHRY) led to rapid phosphorylation of Stat1 on both tyrosine (Y701) and serine (S727) residues in epidermis. CHRY treatment also led to upregulation of unphosphorylated Stat1 (uStat1) at later time points. CHRY treatment also led to upregulation of interferon regulatory factor 1 (IRF-1) mRNA and protein, which was dependent on Stat1. Further analyses demonstrated that topical treatment with CHRY but not TPA upregulated interferon-gamma (IFNγ) mRNA in the epidermis and that the induction of both IRF-1 and uStat1 was dependent on IFNγ signaling. Stat1 deficient (Stat1(-/-) ) mice were highly resistant to skin tumor promotion by CHRY. In contrast, the tumor response (in terms of both papillomas and squamous cell carcinomas) was similar in Stat1(-/-) mice and wild-type littermates with TPA as the promoter. Maximal induction of both cyclooxygenase-2 and inducible nitric oxide synthase in epidermis following treatment with CHRY was also dependent on the presence of functional Stat1. These studies define a novel mechanism associated with skin tumor promotion by the anthrone class of tumor promoters involving upregulation of IFNγ signaling in the epidermis and downstream signaling through activated (phosphorylated) Stat1, IRF-1 and uStat1. © 2014 Wiley Periodicals, Inc.

  16. DELLA genes restrict inflorescence meristem function independently of plant height

    PubMed Central

    Serrano-Mislata, Antonio; Bencivenga, Stefano; Bush, Max; Schiessl, Katharina; Boden, Scott; Sablowski, Robert

    2017-01-01

    Summary DELLA proteins associate with transcription factors to control plant growth in response to gibberellin 1. Semi-dwarf DELLA mutants with improved harvest index and decreased lodging greatly improved global food security during the “green revolution” in the 1960-70s 2. However, DELLA mutants are pleiotropic and the developmental basis for their effects on plant architecture remains poorly understood. Here, we show that DELLA proteins have genetically separable roles in controlling stem growth and the size of the inflorescence meristem, where flowers initiate. Quantitative 3D image analysis, combined with a genome-wide screen for DELLA-bound loci in the inflorescence tip, revealed that DELLAs limit meristem size in Arabidopsis by directly up-regulating the cell cycle inhibitor KRP2 in the underlying rib meristem, without affecting the canonical WUSCHEL-CLAVATA meristem size regulators3. Mutation of KRP2 in a DELLA semi-dwarf background restored meristem size, but not stem growth, and accelerated flower production. In barley, secondary mutations in the DELLA gain of function mutant Sln1d 4 also uncoupled meristem and inflorescence size from plant height. Our work reveals an unexpected and conserved role for DELLA genes in controlling shoot meristem function and suggests how dissection of pleiotropic DELLA functions could unlock further yield gains in semi-dwarf mutants. PMID:28827519

  17. Blockade of PD-1/PD-L1 Promotes Adoptive T-Cell Immunotherapy in a Tolerogenic Environment

    PubMed Central

    Kenna, Tony J.; Galea, Ryan; Large, Justin; Yagita, Hideo; Steptoe, Raymond J.

    2015-01-01

    Adoptive cellular immunotherapy using in vitro expanded CD8+ T cells shows promise for tumour immunotherapy but is limited by eventual loss of function of the transferred T cells through factors that likely include inactivation by tolerogenic dendritic cells (DC). The co-inhibitory receptor programmed death-1 (PD-1), in addition to controlling T-cell responsiveness at effector sites in malignancies and chronic viral diseases is an important modulator of dendritic cell-induced tolerance in naive T cell populations. The most potent therapeutic capacity amongst CD8+ T cells appears to lie within Tcm or Tcm-like cells but memory T cells express elevated levels of PD-1. Based on established trafficking patterns for Tcm it is likely Tcm-like cells interact with lymphoid-tissue DC that present tumour-derived antigens and may be inherently tolerogenic to develop therapeutic effector function. As little is understood of the effect of PD-1/PD-L1 blockade on Tcm-like CD8+ T cells, particularly in relation to inactivation by DC, we explored the effects of PD-1/PD-L1 blockade in a mouse model where resting DC tolerise effector and memory CD8+ T cells. Blockade of PD-1/PD-L1 promoted effector differentiation of adoptively-transferred Tcm-phenotype cells interacting with tolerising DC. In tumour-bearing mice with tolerising DC, effector activity was increased in both lymphoid tissues and the tumour-site and anti-tumour activity was promoted. Our findings suggest PD-1/PD-L1 blockade may be a useful adjunct for adoptive immunotherapy by promoting effector differentiation in the host of transferred Tcm-like cells. PMID:25741704

  18. Blockade of PD-1/PD-L1 promotes adoptive T-cell immunotherapy in a tolerogenic environment.

    PubMed

    Blake, Stephen J P; Ching, Alan L H; Kenna, Tony J; Galea, Ryan; Large, Justin; Yagita, Hideo; Steptoe, Raymond J

    2015-01-01

    Adoptive cellular immunotherapy using in vitro expanded CD8+ T cells shows promise for tumour immunotherapy but is limited by eventual loss of function of the transferred T cells through factors that likely include inactivation by tolerogenic dendritic cells (DC). The co-inhibitory receptor programmed death-1 (PD-1), in addition to controlling T-cell responsiveness at effector sites in malignancies and chronic viral diseases is an important modulator of dendritic cell-induced tolerance in naive T cell populations. The most potent therapeutic capacity amongst CD8+ T cells appears to lie within Tcm or Tcm-like cells but memory T cells express elevated levels of PD-1. Based on established trafficking patterns for Tcm it is likely Tcm-like cells interact with lymphoid-tissue DC that present tumour-derived antigens and may be inherently tolerogenic to develop therapeutic effector function. As little is understood of the effect of PD-1/PD-L1 blockade on Tcm-like CD8+ T cells, particularly in relation to inactivation by DC, we explored the effects of PD-1/PD-L1 blockade in a mouse model where resting DC tolerise effector and memory CD8+ T cells. Blockade of PD-1/PD-L1 promoted effector differentiation of adoptively-transferred Tcm-phenotype cells interacting with tolerising DC. In tumour-bearing mice with tolerising DC, effector activity was increased in both lymphoid tissues and the tumour-site and anti-tumour activity was promoted. Our findings suggest PD-1/PD-L1 blockade may be a useful adjunct for adoptive immunotherapy by promoting effector differentiation in the host of transferred Tcm-like cells.

  19. Effect of rapid warming of boar semen on sperm morphology and physiology.

    PubMed

    Bamba, K; Cran, D G

    1985-09-01

    The effect of rapid dilution (1:8 with BTS or 1:6.5 with KRP) and temperature change on sperm morphology and physiology were studied using boar spermatozoa pre-diluted in BF5 diluent. Rapid dilution of cold semen (5 degrees C) with a warm solution (37 degrees C) caused marked acrosomal changes which were most prominent in the anterior region. The acrosomal damage appeared to be caused mainly by rapid warming. In contrast to rapid cooling, rapid warming had little effect upon motility, glutamic-oxaloacetic transaminase release and respiration.

  20. Immunopotentiator from Pantoea agglomerans 1 (IP-PA1) Promotes Murine Hair Growth and Human Dermal Papilla Cell Gene Expression.

    PubMed

    Wakame, Koji; Okawa, Hiroshi; Komatsu, Ken-Ich; Nakata, Akifumi; Sato, Keisuke; Ingawa, Hiroyuki; Kohchi, Chie; Nishizawa, Takashi; Soma, Gen-Ichiro

    2016-07-01

    The lipopolysaccharide (LPS)-like compound derived from Pantoea agglomerans (immunopotentiator from Pantoea agglomerans 1 (IP-PA1)) has been used not only as dietary supplement or cosmetic for humans, but also by Japanese veterinarians as an anti-tumor, anti-allergy, "keep a fine coat of fur" and hair growth-promoting functional food for dogs and cats. In the present study, we focused on the hair growth-promoting effects of IP-PA1 on a hair-shaved animal model and its mechanism of action. We also investigated its potential on gene expression after stimulating human dermal papilla cells with IP-PA1. The hair on the back of a C3H/HeN mouse was shaved and IP-PA1 was orally administered or applied to the skin. The status of hair growth was observed and recorded for 14 days. Skin was collected and histological tissue examination was performed with respect to hair growth status using hematoxylin and eosin staining. After IP-PA1 administration (2 and 10 μg/ml) to human dermal papilla cell culture system for 24 h, fibroblast growth factor-7 (FGF-7) and vascular endothelial growth factor (VEGF) mRNA expression were measured using real-time polymerase chain reaction (PCR) analysis. IP-PA1, when given orally, showed a tendency to promote hair growth in mice. In addition, skin application also significantly promoted hair growth, while histopathological examinations further demonstrated hair elongation from dermal papilla cells. In the human dermal papilla cell culture system, significant FGF-7 and VEGF mRNA expressions were observed (p<0.05). An underlying mechanism of gene expression by which IP-PA1 promotes hair growth was suggested to be different from that of medicine and traditional hair tonics, such as minoxidil and adenosine. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  1. NCOA1 promotes angiogenesis in breast tumors by simultaneously enhancing both HIF1α- and AP-1-mediated VEGFa transcription

    PubMed Central

    Qin, Li; Xu, Yan; Xu, Yixiang; Ma, Gang; Liao, Lan; Wu, Yelin; Li, Yi; Wang, Xian; Wang, Xiaosong; Jiang, Jun; Wang, Jin; Xu, Jianming

    2015-01-01

    Nuclear receptor coactivator 1 (NCOA1) is overexpressed in a subset of breast cancer and its increased expression positively correlates with disease recurrence and metastasis. Although NCOA1 is known to promote breast cancer metastasis through working with multiple transcription factors to upregulate the expression of Twist1, ITGA5, CSF-1, SDF1 and CXCR4, the role of NCOA1 in breast tumor angiogenesis has not been investigated. In this study, we found that the microvascular density (MVD) was significantly decreased and increased in Ncoa1-knockout and NCOA1-overexpressing mammary tumors, respectively, in several breast cancer mouse models. Knockout or knockdown of NCOA1 in breast cancer cell lines also markedly compromised their capability to induce angiogenesis in Matrigel plugs embedded subcutaneously in mice, while this compromised capability could be rescued by VEGFa treatment. At the molecular level, NCOA1 upregulates VEGFa expression in both mouse mammary tumors and cultured breast cancer cells, and it does so by associating with both c-Fos, which is recruited to the AP-1 site at bp −938 of the VEGFa promoter, and HIF1α, which is recruited to the HIF1α-binding element at bp −979 of the VEGFa promoter, to enhance VEGFa transcription. In 140 human breast tumors, high NCOA1 protein correlates with high MVD and patients with both high NCOA1 and high MVD showed significantly shorter survival time. In summary, this study revealed a novel mechanism that NCOA1 potentiates breast cancer angiogenesis through upregulating HIF1α and AP-1-mediated VEGFa expression, which reinforces the rational of targeting NCOA1 in controlling breast cancer progression and metastasis. PMID:26287601

  2. Glyphosate catabolism by Pseudomonas sp

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shinabarger, D.L.

    1986-01-01

    The pathway for the degradation of glyphosate (N-phosphonomethylglycine) by Pseudomonas sp. PG2982 has been determined using metabolic radiolabeling experiments. Radiorespirometry experiments utilizing (3-/sup 14/C) glyphosate revealed that approximately 50-59% of the C3 carbon was oxidized to CO/sub 2/. Fractionation of stationary phase cells labeled with (3-/sup 14/C)glyphosate revealed that from 45-47% of the assimilated C3 carbon is distributed to proteins and that amino acids methionine and serine are highly labeled. The nucleic acid bases adenine and guanine received 90% of the C3 label that was incorporated into nucleic acids, and the only pyrimidine base labeled was thymine. Pulse labeling ofmore » PG2982 cells with (3-/sup 14/C)glyphosate revealed that (3-/sup 14/C)sarcosine is an intermediate in glyphosate degradation. Examination of crude extracts prepared from PG2982 cells revealed the presence of an enzyme that oxidizes sarcosine to glycine and formaldehyde. These results indicate that the first step in glyphosate degradation by PG2982 is cleavage of the carbon-phosphorus bond, resulting in the release of sarcosine and a phosphate group. The phosphate group is utilized as a source of phosphorus, and the sarcosine is degraded to glycine and formaldehyde. Phosphonate utilization by Pseudomonas sp. PG2982 was investigated. Each of the ten phosphonates tested were utilized as a sole source of phosphorus by PG2982. Representative compounds tested included alkylphosphonates, 1-amino-substituted alkylphosphonates, amino-terminal phosphonates, and an arylphosphonate. PG2982 cultures degraded phenylphosphonate to benzene and produced methane from methylphosphonate. The data indicate that PG2982 is capable of cleaving the carbon-phosphorus bond of several structurally different phosphonates.« less

  3. Lynch syndrome-associated endometrial carcinoma with MLH1 germline mutation and MLH1 promoter hypermethylation: a case report and literature review.

    PubMed

    Yokoyama, Takanori; Takehara, Kazuhiro; Sugimoto, Nao; Kaneko, Keika; Fujimoto, Etsuko; Okazawa-Sakai, Mika; Okame, Shinichi; Shiroyama, Yuko; Yokoyama, Takashi; Teramoto, Norihiro; Ohsumi, Shozo; Saito, Shinya; Imai, Kazuho; Sugano, Kokichi

    2018-05-21

    Lynch syndrome is an autosomal dominant inherited disease caused by germline mutations in mismatch repair genes. Analysis for microsatellite instability (MSI) and immunohistochemistry (IHC) of protein expressions of disease-associated genes is used to screen for Lynch syndrome in endometrial cancer patients. When losses of both MLH1 and PMS2 proteins are observed by IHC, MLH1 promoter methylation analysis is conducted to distinguish Lynch syndrome-associated endometrial cancer from sporadic cancer. Here we report a woman who developed endometrial cancer at the age of 49 years. She had a family history of colorectal cancer (first-degree relative aged 52 years) and stomach cancer (second-degree relative with the age of onset unknown). No other family history was present, and she failed to meet the Amsterdam II criteria for the diagnosis of Lynch syndrome. Losses of MLH1 and PMS2, but not MSH2 and MSH6, proteins were observed by IHC in endometrial cancer tissues. Because MLH1 promoter hypermethylation was detected in endometrial cancer tissue samples, the epigenetic silencing of MLH1 was suspected as the cause of the protein loss. However, because of the early onset of endometrial cancer and the positive family history, a diagnosis of Lynch syndrome was also suspected. Therefore, we provided her with genetic counseling. After obtaining her consent, MLH1 promoter methylation testing and genetic testing of peripheral blood were performed. MLH1 promoter methylation was not observed in peripheral blood. However, genetic testing revealed a large deletion of exon 5 in MLH1; thus, we diagnosed the presence of Lynch syndrome. Both MLH1 germline mutation and MLH1 promoter hypermethylation may be observed in endometrial cancer. Therefore, even if MLH1 promoter hypermethylation is detected, a diagnosis of Lynch syndrome cannot be excluded.

  4. Promoter Targeting RNAs: Unexpected Contributors to the Control of HIV-1 Transcription.

    PubMed

    Suzuki, Kazuo; Ahlenstiel, Chantelle; Marks, Katherine; Kelleher, Anthony D

    2015-01-27

    In spite of prolonged and intensive treatment with combined antiretroviral therapy (cART), which efficiently suppresses plasma viremia, the integrated provirus of HIV-1 persists in resting memory CD4(+) T cells as latent infection. Treatment with cART does not substantially reduce the burden of latent infection. Once cART is ceased, HIV-1 replication recrudesces from these reservoirs in the overwhelming majority of patients. There is increasing evidence supporting a role for noncoding RNAs (ncRNA), including microRNAs (miRNAs), antisense (as)RNAs, and short interfering (si)RNA in the regulation of HIV-1 transcription. This appears to be mediated by interaction with the HIV-1 promoter region. Viral miRNAs have the potential to act as positive or negative regulators of HIV transcription. Moreover, inhibition of virally encoded long-asRNA can induce positive transcriptional regulation, while antisense strands of siRNA targeting the NF-κB region suppress viral transcription. An in-depth understanding of the interaction between ncRNAs and the HIV-1 U3 promoter region may lead to new approaches for the control of HIV reservoirs. This review focuses on promoter associated ncRNAs, with particular emphasis on their role in determining whether HIV-1 establishes active or latent infection.

  5. Promoter Targeting RNAs: Unexpected Contributors to the Control of HIV-1 Transcription

    PubMed Central

    Suzuki, Kazuo; Ahlenstiel, Chantelle; Marks, Katherine; Kelleher, Anthony D

    2015-01-01

    In spite of prolonged and intensive treatment with combined antiretroviral therapy (cART), which efficiently suppresses plasma viremia, the integrated provirus of HIV-1 persists in resting memory CD4+ T cells as latent infection. Treatment with cART does not substantially reduce the burden of latent infection. Once cART is ceased, HIV-1 replication recrudesces from these reservoirs in the overwhelming majority of patients. There is increasing evidence supporting a role for noncoding RNAs (ncRNA), including microRNAs (miRNAs), antisense (as)RNAs, and short interfering (si)RNA in the regulation of HIV-1 transcription. This appears to be mediated by interaction with the HIV-1 promoter region. Viral miRNAs have the potential to act as positive or negative regulators of HIV transcription. Moreover, inhibition of virally encoded long-asRNA can induce positive transcriptional regulation, while antisense strands of siRNA targeting the NF-κB region suppress viral transcription. An in-depth understanding of the interaction between ncRNAs and the HIV-1 U3 promoter region may lead to new approaches for the control of HIV reservoirs. This review focuses on promoter associated ncRNAs, with particular emphasis on their role in determining whether HIV-1 establishes active or latent infection. PMID:25625613

  6. Astaxanthin prevents pulmonary fibrosis by promoting myofibroblast apoptosis dependent on Drp1-mediated mitochondrial fission.

    PubMed

    Zhang, Jinjin; Xu, Pan; Wang, Youlei; Wang, Meirong; Li, Hongbo; Lin, Shengcui; Mao, Cuiping; Wang, Bingsi; Song, Xiaodong; Lv, Changjun

    2015-09-01

    Promotion of myofibroblast apoptosis is a potential therapeutic strategy for pulmonary fibrosis. This study investigated the antifibrotic effect of astaxanthin on the promotion of myofibroblast apoptosis based on dynamin-related protein-1 (Drp1)-mediated mitochondrial fission in vivo and in vitro. Results showed that astaxanthin can inhibit lung parenchymal distortion and collagen deposition, as well as promote myofibroblast apoptosis. Astaxanthin demonstrated pro-apoptotic function in myofibroblasts by contributing to mitochondrial fission, thereby leading to apoptosis by increasing the Drp1 expression and enhancing Drp1 translocation into the mitochondria. Two specific siRNAs were used to demonstrate that Drp1 is necessary to promote astaxanthin-induced mitochondrial fission and apoptosis in myofibroblasts. Drp1-associated genes, such as Bcl-2-associated X protein, cytochrome c, tumour suppressor gene p53 and p53-up-regulated modulator of apoptosis, were highly up-regulated in the astaxanthin group compared with those in the sham group. This study revealed that astaxanthin can prevent pulmonary fibrosis by promoting myofibroblast apoptosis through a Drp1-dependent molecular pathway. Furthermore, astaxanthin provides a potential therapeutic value in pulmonary fibrosis treatment. © 2015 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  7. The complete sequence and promoter activity of the human A-raf-1 gene (ARAF1)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lee, J.E.; Beck, T.W.; Brennscheidt, U.

    1994-03-01

    The raf proto-oncogenes encode cytoplasmic protein serine/threonine kinases, which play a critical role in cell growth and development. One of these, A-raf-1 (human gene symbol, ARAF1), which is predominantly expressed in mouse urogenital tissues, has been mapped to an evolutionarily conserved linkage group composed of ARAF1, SYN1, TIMP, and properdin located at human chromosome Xp11.2. The authors have isolated human genomic DNA clones containing the expressed gene (ARAF1) on the X chromosome and a pseudogene (ARAF2) on chromosome 7p12-q11.21. Analysis of the nucleotide sequence from the ARAF1 genomic clones demonstrated that it consists of 16 exons encoded by minimally 10,776more » nucleotides. The major transcriptional start site (+1) was determined by RNase protection and primer extension assays. Promoter activity was confirmed by functional assays using DNA fragments fused to a CAT reporter gene. The ARAF1 minimal promoter, located between nucleotides -59 and +93, has a low G + C content and lacks consensus TATA and Inr sequences but shows sequence similarity at position -1 to the E box that is known to interact with USF and TFII-I transcription factors. 65 refs., 7 figs., 1 tab.« less

  8. High density lipoprotein promotes proliferation of adipose-derived stem cells via S1P1 receptor and Akt, ERK1/2 signal pathways.

    PubMed

    Shen, Haitao; Zhou, Enchen; Wei, Xiujing; Fu, Zhiwei; Niu, Chenguang; Li, Yang; Pan, Bing; Mathew, Anna V; Wang, Xu; Pennathur, Subramaniam; Zheng, Lemin; Wang, Yongyu

    2015-05-15

    Adipose-derived stem cells (ADSC) are non-hematopoietic mesenchymal stem cells that have shown great promise in their ability to differentiate into multiple cell lineages. Their ubiquitous nature and the ease of harvesting have attracted the attention of many researchers, and they pose as an ideal candidate for applications in regenerative medicine. Several reports have demonstrated that transplanting ADSC can promote repair of injured tissue and angiogenesis in animal models. Survival of these cells after transplant remains a key limiting factor for the success of ADSC transplantation. Circulating factors like High Density Lipoprotein (HDL) has been known to promote survival of other stems cells like bone marrow derived stem cells and endothelial progenitor cells, both by proliferation and by inhibiting cell apoptosis. The effect of HDL on transplanted adipose-derived stem cells in vivo is largely unknown. This study focused on exploring the effects of plasma HDL on ADSC and delineating the mechanisms involved in their proliferation after entering the bloodstream. Using the MTT and BrdU assays, we tested the effects of HDL on ADSC proliferation. We probed the downstream intracellular Akt and ERK1/2 signaling pathways and expression of cyclin proteins in ADSC using western blot. Our study found that HDL promotes proliferation of ADSC, by binding to sphingosine-1- phosphate receptor-1(S1P1) on the cell membrane. This interaction led to activation of intracellular Akt and ERK1/2 signaling pathways, resulting in increased expression of cyclin D1 and cyclin E, and simultaneous reduction in expression of cyclin-dependent kinase inhibitors p21 and p27, therefore promoting cell cycle progression and cell proliferation. These studies raise the possibility that HDL may be a physiologic regulator of stem cells and increasing HDL concentrations may be valuable strategy to promote ADSC transplantation.

  9. MAGE-A1 promotes melanoma proliferation and migration through C-JUN activation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Dong; The 309th Hospital of China People's Liberation Army, Beijing 100091; Wang, Junyun

    2016-05-13

    MAGE-A1 belongs to the chromosome X-clustered genes of cancer-testis antigen family and is normally expressed in the human germ line but is also overexpressed in various tumors. Previous studies of MAGE-A1 in melanoma mainly focused on methylation changes or its role in immunotherapy, however, its biological functions in melanoma have remained unknown. In order to determine the role of MAGE-A1 in melanoma growth and metastasis, we manipulated melanoma cell lines with overexpression and knockdown of MAGE-A1. Integration of cell proliferation assays, transwell migration and invasion assays, and RNA-Seq analysis revealed that up-regulation of MAGE-A1 dramatically promoted proliferation, migration, and invasionmore » of human melanoma cell lines in vitro, while down-regulation of MAGE-A1 inhibited those characteristics associated with tumor cells. Furthermore, transcriptome sequencing revealed that MAGE-A1 exerts its tumor promoting activity by activating p-C-JUN directly or through ERK-MAPK signaling pathways. Based on our findings, we propose that MAGE-A1 may be a potential therapeutic target for melanoma patients. - Highlights: • MAGE-A1 promotes proliferation and clone formation in melanoma cell lines. • MAGE-A1 enhances tumor cell migration and invasion in melanoma cell lines. • Network including C-JUN, IL8, and ARHGAP29 play critical role in malignant melanoma. • Oncogenic MAGE-A1 increases p-C-JUN levels, possibly via ERK-MAPK signaling pathway.« less

  10. The Necrosome Promotes Pancreas Oncogenesis via CXCL1 and Mincle Induced Immune Suppression

    PubMed Central

    Seifert, Lena; Werba, Gregor; Tiwari, Shaun; Giao Ly, Nancy Ngoc; Alothman, Sara; Alqunaibit, Dalia; Avanzi, Antonina; Barilla, Rocky; Daley, Donnele; Greco, Stephanie H.; Torres-Hernandez, Alejandro; Pergamo, Matthew; Ochi, Atsuo; Zambirinis, Constantinos P.; Pansari, Mridul; Rendon, Mauricio; Tippens, Daniel; Hundeyin, Mautin; Mani, Vishnu R.; Hajdu, Cristina; Engle, Dannielle; Miller, George

    2016-01-01

    Neoplastic pancreatic epithelial cells are widely believed to die via Caspase 8-dependant apoptotic cell death and chemotherapy is thought to further promote tumor apoptosis1. Conversely, disruption of apoptosis is a basic modality cancer cells exploit for survival2,3. However, the role of necroptosis, or programmed necrosis, in pancreatic ductal adenocarcinoma (PDA) is uncertain. There are a multitude of potential inducers of necroptosis in PDA including ligation of TNFR1, CD95, TRAIL receptors, Toll-like receptors, ROS, and Chemotherapeutics4,5. Here we report that the principal components of the necrosome, RIP1 and RIP3, are highly expressed in PDA and are further upregulated by chemotherapy. Blockade of the necrosome in vitro promoted cancer cell proliferation and induced an aggressive oncogenic phenotype. By contrast, in vivo RIP3 deletion or RIP1 inhibition was protective against oncogenic progression and was associated with the development of a highly immunogenic myeloid and T cell infiltrate. The immune-suppressive tumor microenvironment (TME) associated with intact RIP1/RIP3 signaling was in-part contingent on necroptosis-induced CXCL1 expression whereas CXCL1 blockade was protective against PDA. Moreover, we found that cytoplasmic SAP130 was expressed in PDA in a RIP1/RIP3-dependent manner, and Mincle – its cognate receptor – was upregulated in tumor-infiltrating myeloid cells. Mincle ligation by SAP130 promoted oncogenesis whereas Mincle deletion was protective and phenocopied the immunogenic reprogramming of the TME characteristic of RIP3 deletion. Cellular depletion experiments suggested that whereas inhibitory macrophages promote tumorigenesis in PDA, they lose their immune-suppressive effects in the context of RIP3 or Mincle deletion. As such, T cells which are dispensable to PDA progression in hosts with intact RIP3 or Mincle signaling become reprogrammed into indispensable mediators of anti-tumor immunity in absence of RIP3 or Mincle. Our work

  11. An NPC1L1 gene promoter variant is associated with autosomal dominant hypercholesterolemia.

    PubMed

    Martín, B; Solanas-Barca, M; García-Otín, A-L; Pampín, S; Cofán, M; Ros, E; Rodríguez-Rey, J-C; Pocoví, M; Civeira, F

    2010-05-01

    A substantial number of subjects with autosomal dominant hypercholesterolemia (ADH) do not have LDL receptor (LDLR) or apolipoprotein B (APOB) mutations. Some ADH subjects appear to hyperabsorb sterols from the intestine, thus we hypothesized that they could have variants of the Niemann-Pick C1-Like 1 gene (NPC1L1). NPC1L1 encodes a crucial protein involved in intestinal sterol absorption. Four NPC1L1 variants (-133A>G, -18C>A, 1679C>G, 28650A>G) were analyzed in 271 (155 women and 116 men) ADH bearers without mutations in LDLR or APOB aged 30-70years and 274 (180 women and 94 men) control subjects aged 25-65years. The AC haplotype determined by the -133A>G and -18C>A variants was underrepresented in ADH subjects compared to controls (p=0.01). In the ADH group, cholesterol absorption/synthesis markers were significantly lower in AC homozygotes that in all others haplotypes. Electrophoretic mobility shift assay (EMSA) results revealed that the -133A-specific oligonucleotide produced a retarded band stronger than the -133G allele. Luciferase activity with NPC1L1 -133G variant was 2.5-fold higher than with the -133A variant. The -133A>G polymorphism exerts a significant effect on NPC1L1 promoter activity. NPC1L1 promoter variants might explain in part the hypercholesterolemic phenotype of some subjects with nonLDLR/nonAPOB ADH. Copyright 2009 Elsevier B.V. All rights reserved.

  12. Cav-1 promotes atherosclerosis by activating JNK-associated signaling.

    PubMed

    Wang, Dong-Xia; Pan, Yong-Quan; Liu, Bing; Dai, Li

    2018-05-07

    The objective of the study is to calculate the role and underlying the molecular mechanisms of caveolin-1 (Cav-1) in atherosclerosis (AS). Cav-1 was mainly expressed in the endothelial cells of atherosclerotic lesions in both human patients and apolipoprotein E deficient (ApoE -/- ) mice. Cav-1 deficiency (Cav-1 -/- ) attenuated high-fat diet (HFD)-induced atherosclerotic lesions in ApoE -/- mice, supported by the reduced aortic plaques. Cav-1 -/- reduced the macrophage content and decreased the release of inflammation-related cytokines or chemokine in serum or abdominal aortas, accompanied with the inactivation of inhibitor κB kinase κ (IKKβ)/p65/IκBα signaling pathway. Also, the activity of mitogen-activated protein kinases 7/c-Jun-N-terminal kinase (MKK7/JNK) signaling was decreased by Cav-1 -/- . In addition, oxidative stress induced by HFD in ApoE -/- mice was alleviated by Cav-1 -/- . In response to HFD, Cav-1 -/- markedly reduced triglyceride (TG), total cholesterol (TC), low-density lipoprotein-cholesterol (LDLC) and very low-density lipoprotein-cholesterol (VLDLC) in serum of HFD-fed ApoE -/- mice, whereas enhanced high-density lipoprotein-cholesterol (HDLC) contents. Consistent with these findings, haematoxylin and eosin (H&E) and Oil Red O staining showed fewer lipid droplets in the liver of Cav-1-deficient mice. Further, real time-quantitative PCR (RT-qPCR) analysis indicated that Cav-1 -/- alleviated dyslipidemia both in liver and abdominal aortas of ApoE -/- mice fed with HFD. Cav-1 inhibition-induced attenuation of inflammatory response, oxidative stress and dyslipidemia were confirmed in vitro using mouse vascular smooth muscle cells (VSMCs) treated with ox-LDL. Surprisingly, the processes regulated by Cav-1-knockdown could be abolished through promoting JNK activation in ox-LDL-treated VSMCs. In conclusion, Cav-1 expression could promote HFD-induced AS in a JNK-dependent manner. Copyright © 2018. Published by Elsevier Inc.

  13. Cloning of cardiac, kidney, and brain promoters of the feline ncx1 gene.

    PubMed

    Barnes, K V; Cheng, G; Dawson, M M; Menick, D R

    1997-04-25

    The Na+-Ca2+ exchanger (NCX1) plays a major role in calcium efflux and therefore in the control and regulation of intracellular calcium in the heart. The exchanger has been shown to be regulated at several levels including transcription. NCX1 mRNA levels are up-regulated in both cardiac hypertrophy and failure. In this work, the 5'-end of the ncx1 gene has been cloned to study the mechanisms that mediate hypertrophic stimulation and cardiac expression. The feline ncx1 gene has three exons that encode 5'-untranslated sequences that are under the control of three tissue-specific promoters. The cardiac promoter drives expression in cardiocytes, but not in mouse L cells. Although it contains at least one enhancer (-2000 to -1250 base pairs (bp)) and one or more negative elements (-1250 to -250 bp), a minimum promoter (-250 to +200 bp) is sufficient for cardiac expression and alpha-adrenergic stimulation.

  14. Oncogenic Ras regulates BRIP1 expression to induce dissociation of BRCA1 from chromatin, inhibit DNA repair, and promote senescence

    PubMed Central

    Tu, Zhigang; Aird, Katherine M.; Bitler, Benjamin G.; Nicodemus, Jasmine P.; Beeharry, Neil; Xia, Bing; Yen, Tim J.; Zhang, Rugang

    2011-01-01

    Summary Here, we report a cell-intrinsic mechanism by which oncogenic RAS promotes senescence while predisposing cells to senescence bypass by allowing for secondary hits. We show that oncogenic RAS inactivates the BRCA1 DNA repair complex by dissociating BRCA1 from chromatin. This event precedes senescence-associated cell cycle exit and coincides with the accumulation of DNA damage. Downregulation of BRIP1, a physiological partner of BRCA1 in the DNA repair pathway, triggers BRCA1 chromatin dissociation. Conversely, ectopic BRIP1 rescues BRCA1 chromatin dissociation and suppresses RAS-induced senescence and the DNA damage response. Significantly, cells undergoing senescence do not exhibit a BRCA1-dependent DNA repair response when exposed to DNA damage. Overall, our study provides a molecular basis by which oncogenic RAS promotes senescence. Since DNA damage has the potential to produce additional "hits" that promote senescence bypass, our findings may also suggest one way a small minority of cells might bypass senescence and contribute to cancer development. PMID:22137763

  15. HBV core promoter mutations promote cellular proliferation through E2F1-mediated upregulation of S-phase kinase-associated protein 2 transcription.

    PubMed

    Huang, Yuehua; Tai, Andrew W; Tong, Shuping; Lok, Anna S F

    2013-06-01

    Hepatitis B virus (HBV) core promoter (CP) mutations have been associated with an increased risk of hepatocellular carcinoma (HCC) in clinical studies. We previously reported that a combination of CP mutations seen in HCC patients, expressed in HBx gene, increased SKP2 (S-phase kinase-associated protein 2) expression, thereby promoting cellular proliferation. Here, we investigate the possible mechanisms by which CP mutations upregulate SKP2. We used immunoblotting and ATPlite assay to validate the effect of CP mutations in full-length HBV genome on cell cycle regulator levels and cell proliferation. Activation of SKP2 mRNA was assessed by quantitative real-time PCR in primary human hepatocytes (PHH) and HCC cell lines. Effect of CP mutations on SKP2 promoter activity was determined by luciferase assay. Target regulation of E2F1 on SKP2 was analyzed by siRNAs. CP mutations in full-length HBV genome upregulated SKP2 expression, thereby downregulating cell cycle inhibitors and accelerating cellular proliferation. CP mutations enhanced SKP2 promoter activity but had no effect on SKP2 protein stability. Mapping of the SKP2 promoter identified a region necessary for activation by CP mutations that contains an E2F1 response element. Knocking down E2F1 reduced the effects of CP mutations on SKP2 and cellular proliferation. The effect of CP mutations on E2F1 might be mediated through hyperphosphorylation of RB. HBV CP mutations enhance SKP2 transcription by activating the E2F1 transcription factor and in turn downregulate cell cycle inhibitors, thus providing a potential mechanism for an association between CP mutations and HCC. Copyright © 2013 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

  16. The SANT domain of human MI-ER1 interacts with Sp1 to interfere with GC box recognition and repress transcription from its own promoter.

    PubMed

    Ding, Zhihu; Gillespie, Laura L; Mercer, F Corinne; Paterno, Gary D

    2004-07-02

    To gain insight into the regulation of hmi-er1 expression, we cloned a human genomic DNA fragment containing one of the two hmi-er1 promoters and consisting of 1460 bp upstream of the translation initiation codon of hMI-ER1. Computer-assisted sequence analysis revealed that the hmi-er1 promoter region contains a CpG island but lacks an identifiable TATA element, initiator sequence and downstream promoter element. This genomic DNA was able to direct transcription of a luciferase reporter gene in a variety of human cell lines, and the minimal promoter was shown to be located within-68/+144 bp. Several putative Sp1 binding sites were identified, and we show that Sp1 can bind to the hmi-er1 minimal promoter and increase transcription, suggesting that the level of hmi-er1 expression may depend on the availability of Sp1 protein. Functional analysis revealed that hMI-ER1 represses Sp1-activated transcription from the minimal promoter by a histone deacetylase-independent mechanism. Chromatin immunoprecipitation analysis demonstrated that both Sp1 and hMI-ER1 are associated with the chromatin of the hmi-er1 promoter and that overexpression of hMI-ER1 in cell lines that allow Tet-On-inducible expression resulted in loss of detectable Sp1 from the endogenous hmi-er1 promoter. The mechanism by which this occurs does not involve binding of hMI-ER1 to cis-acting elements. Instead, we show that hMI-ER1 physically associates with Sp1 and that endogenous complexes containing the two proteins could be detected in vivo. Furthermore, hMI-ER1 specifically interferes with binding of Sp1 to the hmi-er1 minimal promoter as well as to an Sp1 consensus oligonucleotide. Deletion analysis revealed that this interaction occurs through a region containing the SANT domain of hMI-ER1. Together, these data reveal a functional role for the SANT domain in the action of co-repressor regulatory factors and suggest that the association of hMI-ER1 with Sp1 represents a novel mechanism for the negative

  17. Epigenetics in type 1 diabetes: TNFa gene promoter methylation status in Chilean patients with type 1 diabetes mellitus.

    PubMed

    Arroyo-Jousse, Viviana; Garcia-Diaz, Diego F; Codner, Ethel; Pérez-Bravo, Francisco

    2016-12-01

    TNF-α is a pro-inflammatory cytokine that is involved in type 1 diabetes (T1D) pathogenesis. The TNFa gene is subject of epigenetic regulation in which folate and homocysteine are important molecules because they participate in the methionine cycle where the most important methyl group donor (S-adenosylmethionine) is formed. We investigated whether TNFa gene promoter methylation status in T1D patients was related to blood folate, homocysteine and TNF-α in a transversal case-control study. We studied T1D patients (n 25, mean=13·7 years) and healthy control subjects (n 25, mean=31·1 years), without T1D and/or other autoimmune diseases or direct family history of these diseases. A blood sample was obtained for determination of serum folate, plasma homocysteine and TNF-α concentrations. Whole blood was used for the extraction of DNA to determine the percentage of methylation by real-time PCR and melting-curve analysis. Results are expressed as means and standard deviations for parametric variables and as median (interquartile range) for non-parametric variables. T1D patients showed a higher TNFa gene promoter methylation (39·2 (sd 19·5) %) when compared with control subjects (25·4 (sd 13·7) %) (P=0·008). TNFa gene promoter methylation was positively associated only with homocysteine levels in T1D patients (r 0·55, P=0·007), but not in control subjects (r -0·122, P=0·872). To our knowledge, this is the first work that reports the methylation status of the TNFa gene promoter and its relationship with homocysteine metabolism in Chilean T1D patients without disease complications.

  18. APC promoter 1B deletion in seven American families with familial adenomatous polyposis.

    PubMed

    Snow, A K; Tuohy, T M F; Sargent, N R; Smith, L J; Burt, R W; Neklason, D W

    2015-10-01

    Familial adenomatous polyposis (FAP) is a colorectal cancer predisposition syndrome caused by mutations in the adenomatous polyposis coli (APC) gene. Clinical genetic testing fails to identify disease causing mutations in up to 20% of clinically apparent FAP cases. Following the inclusion of multiplex ligation-dependent probe amplification (MLPA) probes specific for APC promoter 1B, seven probands were identified with a deletion of promoter 1B. Using haplotype analysis spanning the APC locus, the seven families appear to be identical by descent from a common founder. The clinical phenotype of 19 mutation carriers is classical FAP with colectomy at an average age of 24. The majority of cases had a large number of duodenal and gastric polyps. Measurements of allele-specific expression of APC mRNA using TaqMan assay confirmed that relative expression in the allele containing the promoter 1B deletion was reduced 42-98%, depending on tissue type. This study confirms the importance of APC promoter deletions as a cause of FAP and identifies a founder mutation in FAP patients from the United States. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  19. Matrix Metalloproteinase-1 (MMP-1) Promoter Polymorphisms are Well Linked with Lower Stomach Tumor Formation in Eastern Indian Population

    PubMed Central

    Dey, Sanjib; Ghosh, Nillu; Saha, Debjit; Kesh, Kousik; Gupta, Arnab; Swarnakar, Snehasikta

    2014-01-01

    Expression of matrix metalloproteinase-1 (MMP-1), an interstitial collagenase, plays a major role in cellular invasion during development of gastric cancer, a leading cause of death worldwide. A single-nucleotide polymorphism (SNP) −1607 1G/2G site of the MMP-1 gene promoter has been reported to alter transcription level. While the importance’s of other SNPs in the MMP-1 promoter have not yet been studied in gastric cancer, our aim was to investigate MMP-1 gene promoter polymorphisms and gastric cancer susceptibility in eastern Indian population. A total of 145 gastric cancer patients and 145 healthy controls were genotyped for MMP-1 −1607 1G/2G (rs1799750) by PCR-restriction fragment length polymorphism (RFLP), while MMP-1 −519 A/G (rs1144393), MMP-1 −422 T/A (rs475007), MMP-1 −340 T/C (rs514921) and MMP-1 −320 T/C (rs494379) were genotyped by DNA sequencing. A positive association was found with MMP-1 −422 T/A SNP that showed significant risk for regional lymph node metastasis (P = 0.021, Odd’s ratio (OR) = 3.044, Confidence intervals (CI) = 1.187–7.807). In addition, we found a significant association with lower stomach tumor formation among gastric cancer patients for three adjacent polymorphisms near the transcriptional start sites of [MMP-1 −422 T/A (P = 0.043, OR = 2.182, CI = 1.03–4.643), MMP-1 −340 T/C (P = 0.075, OR = 1.97, CI = 0.94–4.158) and MMP-1 −320 T/C (P = 0.034, OR = 2.224, CI = 1.064–40731)]. MMP-1 level in patients’ serum was correlated with MMP-1 promoter haplotypes conferring these three SNPs to evaluate the functional importance of these polymorphisms in lower stomach tumor formation and significant correlation was observed. Furthermore, MMP-1 −519 A/G polymorphism displayed poor cellular differentiation (P = 0.024, OR = 3.8, CI = 1.69–8.56) attributing a higher risk of cancer progression. In conclusion, MMP-1 proximal promoter SNPs are

  20. The left end of rat L1 (L1Rn, long interspersed repeated) DNA which is a CpG island can function as a promoter.

    PubMed Central

    Nur, I; Pascale, E; Furano, A V

    1988-01-01

    Here we report that the 600 bp promoter-like region at the left end of a newly isolated and characterized rat L1 DNA element can activate the prokaryotic chloramphenicol acyltransferase gene in a rat cell line. Activation only occurs when the promoter region is oriented to the transferase gene as it is to the L1 protein encoding sequences and is 75% inhibited by methylation of just 5 of the 22 CpGs present in the promoter. The G + C rich promoter contains enough CpGs to qualify it as a CpG island, but in contrast to other CpG islands, genomic L1 promoters are fully methylated in both somatic cell and sperm DNA as judged by restriction enzyme analysis. Partial demethylation of the genomic promoters by treatment with 5-azacytidine failed to produce discrete L1 transcripts. The relationship of methylation to the evolutionary history and fate of the rat L1 promoter is discussed. Images PMID:2459662

  1. Inhibition of FOXO1/3 promotes vascular calcification.

    PubMed

    Deng, Liang; Huang, Lu; Sun, Yong; Heath, Jack M; Wu, Hui; Chen, Yabing

    2015-01-01

    Vascular calcification is a characteristic feature of atherosclerosis, diabetes mellitus, and end-stage renal disease. We have demonstrated that activation of protein kinase B (AKT) upregulates runt-related transcription factor 2 (Runx2), a key osteogenic transcription factor that is crucial for calcification of vascular smooth muscle cells (VSMC). Using mice with SMC-specific deletion of phosphatase and tensin homolog (PTEN), a major negative regulator of AKT, the present studies uncovered a novel molecular mechanism underlying PTEN/AKT/FOXO (forkhead box O)-mediated Runx2 upregulation and VSMC calcification. SMC-specific PTEN deletion mice were generated by crossing PTEN floxed mice with SM22α-Cre transgenic mice. The PTEN deletion resulted in sustained activation of AKT that upregulated Runx2 and promoted VSMC calcification in vitro and arterial calcification ex vivo. Runx2 knockdown did not affect proliferation but blocked calcification of the PTEN-deficient VSMC, suggesting that PTEN deletion promotes Runx2-depedent VSMC calcification that is independent of proliferation. At the molecular level, PTEN deficiency increased the amount of Runx2 post-transcriptionally by inhibiting Runx2 ubiquitination. AKT activation increased phosphorylation of FOXO1/3 that led to nuclear exclusion of FOXO1/3. FOXO1/3 knockdown in VSMC phenocopied the PTEN deficiency, demonstrating a novel function of FOXO1/3, as a downstream signaling of PTEN/AKT, in regulating Runx2 ubiquitination and VSMC calcification. Using heterozygous SMC-specific PTEN-deficient mice and atherogenic ApoE(-/-) mice, we further demonstrated AKT activation, FOXO phosphorylation, and Runx2 ubiquitination in vascular calcification in vivo. Our studies have determined a new causative effect of SMC-specific PTEN deficiency on vascular calcification and demonstrated that FOXO1/3 plays a crucial role in PTEN/AKT-modulated Runx2 ubiquitination and VSMC calcification. © 2014 American Heart Association, Inc.

  2. Isolation and characterization of cyp19a1a and cyp19a1b promoters in the protogynous hermaphrodite orange-spotted grouper (Epinephelus coioides).

    PubMed

    Zhang, Weimin; Lu, Huijie; Jiang, Haiyan; Li, Mu; Zhang, Shen; Liu, Qiongyou; Zhang, Lihong

    2012-02-01

    Aromatase (CYP19A1) catalyzes the conversion of androgens to estrogens. In teleosts, duplicated copies of cyp19a1 genes, namely cyp19a1a and cyp19a1b, were identified, however, the transcriptional regulation of these two genes remains poorly understood. In the present study, the 5'-flanking regions of the orange-spotted grouper cyp19a1a (gcyp19a1a) and cyp19a1b (gcyp19a1b) genes were isolated and characterized. The proximal promoter regions of both genes were relatively conserved when compared to those of the other teleosts. Notably, a conserved FOXO transcriptional factor binding site was firstly reported in the proximal promoter of gcyp19a1a, and deletion of the region (-112 to -60) containing this site significantly decreased the promoter activities. The deletion of the region (-246 to -112) containing the two conserved FTZ-F1 sites also dramatically decreased the transcriptional activities of gcyp19a1a promoter, and both two FTZ-F1 sites were shown to be stimulatory cis-acting elements. A FTZ-F1 homologue isolated from ricefield eel (eFTZ-F1) up-regulated gcyp19a1a promoter activities possibly via the FTZ-F1 sites, however, a previously identified orange-spotted grouper FTZ-F1 homologue (gFTZ-F1) did not activate the transcription of gcyp19a1a promoter unexpectedly. As to gcyp19a1b promoter, all the deletion constructs did not show good promoter activities in either TM4 or U251-MG cells. Estradiol (100nM) up-regulated gcyp19a1b promoter activities by about 13- and 36-fold in TM4 and U251-MG cells, respectively, via the conserved ERE motif, but did not stimulate gcyp19a1a promoter activities. These results are helpful to further elucidate the regulatory mechanisms of cyp19a1a and cyp19a1b expression in the orange-spotted grouper as well as other teleosts. Copyright © 2011 Elsevier Inc. All rights reserved.

  3. Cloning, cell-type specificity, and regulatory function of the mouse alpha(1B)-adrenergic receptor promoter.

    PubMed

    Zuscik, M J; Piascik, M T; Perez, D M

    1999-12-01

    The functionality of a 3422-base pair promoter fragment from the mouse alpha(1B)-adrenergic receptor (alpha(1B)AR) gene was examined. This fragment, cloned from a mouse genomic library, was found to have significant sequence homology to the known human and rat alpha(1B)AR promoters. However, the consensus motif of several key cis-acting elements is not conserved among the rat, human, and mouse genes, suggesting species specificity. Confirming fidelity of the murine promoter, robust in vitro expression of a chloramphenicol acetyltransferase (CAT) reporter was detected in known alpha(1B)AR-expressing BC(3)H1, NB41A3, and DDT(1)MF-2 cells transiently transfected with a promoter-CAT construct. Conversely, minimal CAT expression was detected in known alpha(1B)AR-negative RAT-1 and R3T3 cells. These findings were extended by transfecting the same promoter-CAT construct into various primary cell types. In support of the hypothesis that alpha(1)ARs are differentially expressed in the smooth muscle of the vasculature, primary cultures of superior mesenteric and renal artery vascular smooth muscle cells showed significantly stronger CAT expression than did vascular smooth muscle cells derived from pulmonary, femoral, and iliac arteries. Primary osteoblastic bone-forming cells, which are known to be alpha(1B)AR negative, showed minimal CAT expression. Indicating regulatory function through cis-acting elements, RAT-1, R3T3, NB41A3, BC(3)H1, and DDT(1)MF2 cells transfected with the promoter-CAT construct all showed increased CAT production when challenged with forskolin or hypoxic conditions. Additionally, tissue-specific regulation of the promoter was observed when cells were simultaneously challenged with both forskolin and hypoxia. These results collectively demonstrate that a 3.4-kb PvuII fragment of the murine alpha(1B)AR gene promoter can: 1) drive tissue-specific production of a CAT reporter in both clonal and primary cell lines; and 2) confer tissue-specific regulation

  4. Long noncoding RNA PVT1 promotes EMT via mediating microRNA-186 targeting of Twist1 in prostate cancer.

    PubMed

    Chang, Zhongwen; Cui, Jun; Song, Yongsheng

    2018-05-15

    The pathogenesis and the underlying mechanism of endothelial-mesenchymal transition in prostate cancer remain unclear. Plasmacytoma variant translocation 1 (PVT1), a novel long non-coding RNA maps to 8q24.21, and in many tumor studies the up-regulation of PVT1 has already been reported. PVT1 is closely related to tumor cell proliferation, invasion, and metastasis. In this study, we employed a combination of techniques to study the role of PVT1 in prostate cancer, which included bioinformatic analysis, Western blotting and cell migration assays of prostate cancer cell lines. We report that PVT1 promotes prostate cancer invasion and metastasis by modulating EMT. Furthermore, PVT1 can promote EMT by up-regulation of Twist1, a transcription factor associated with EMT. We then confirmed that PVT1 acts as a sponge for miRNA-186-5p and positively regulates Twist1 by a sponge effect. Therefore, this study has revealed a novel MECHANISM for the promotion of EMT in prostate cancer by PVT1. Our findings suggest that the PVT1/miR-186/Twist1 regulatory axis may be a new therapeutic target for prostate cancer. Copyright © 2018. Published by Elsevier B.V.

  5. Interplay between Notch1 and Notch3 promotes EMT and tumor initiation in squamous cell carcinoma.

    PubMed

    Natsuizaka, Mitsuteru; Whelan, Kelly A; Kagawa, Shingo; Tanaka, Koji; Giroux, Veronique; Chandramouleeswaran, Prasanna M; Long, Apple; Sahu, Varun; Darling, Douglas S; Que, Jianwen; Yang, Yizeng; Katz, Jonathan P; Wileyto, E Paul; Basu, Devraj; Kita, Yoshiaki; Natsugoe, Shoji; Naganuma, Seiji; Klein-Szanto, Andres J; Diehl, J Alan; Bass, Adam J; Wong, Kwok-Kin; Rustgi, Anil K; Nakagawa, Hiroshi

    2017-11-24

    Notch1 transactivates Notch3 to drive terminal differentiation in stratified squamous epithelia. Notch1 and other Notch receptor paralogs cooperate to act as a tumor suppressor in squamous cell carcinomas (SCCs). However, Notch1 can be stochastically activated to promote carcinogenesis in murine models of SCC. Activated form of Notch1 promotes xenograft tumor growth when expressed ectopically. Here, we demonstrate that Notch1 activation and epithelial-mesenchymal transition (EMT) are coupled to promote SCC tumor initiation in concert with transforming growth factor (TGF)-β present in the tumor microenvironment. We find that TGFβ activates the transcription factor ZEB1 to repress Notch3, thereby limiting terminal differentiation. Concurrently, TGFβ drives Notch1-mediated EMT to generate tumor initiating cells characterized by high CD44 expression. Moreover, Notch1 is activated in a small subset of SCC cells at the invasive tumor front and predicts for poor prognosis of esophageal SCC, shedding light upon the tumor promoting oncogenic aspect of Notch1 in SCC.

  6. Association between arginine vasopressin 1a receptor (AVPR1a) promoter region polymorphisms and prepulse inhibition.

    PubMed

    Levin, Raz; Heresco-Levy, Uriel; Bachner-Melman, Rachel; Israel, Salomon; Shalev, Idan; Ebstein, Richard P

    2009-07-01

    Arginine vasopressin and the arginine vasopressin 1a (AVPR1a) gene contribute to a range of social behaviors both in lower vertebrates and in humans. Human promoter-region microsatellite repeat regions (RS1 and RS3) in the AVPR1a gene region have been associated with autism spectrum disorders, prosocial behavior and social cognition. Prepulse inhibition (PPI) of the startle response to auditory stimuli is a largely autonomic response that resonates with social cognition in both animal models and humans. Reduced PPI has been observed in disorders including schizophrenia that are distinguished by deficits in social skills. In the current investigation association was examined between PPI and the AVPR1a RS1 and RS repeat regions and PPI in a group of 113 nonclinical subjects. Using a robust family-based strategy, association was observed between AVPR1a promoter-region repeat length, especially RS3) and PPI (30 ms: global p=0.04; 60 ms p=0.006; 120 ms p=0.008). Notably, longer RS3 alleles were associated with greater levels of prepulse inhibition. Using a short/long classification scheme for the repeat regions, significant association was also observed between all three PPI intervals (30, 60 and 120 ms) and both RS1 and RS3 polymorphisms (PBAT: FBAT-PC(2) statistic p=0.047). Tests of within-subject effects (SPSS GLM) showed significant sexxRS3 interactions at 30 ms (p=0.045) and 60 ms (p=0.01). Longer alleles, especially in male subjects, are associated with significantly higher PPI response, consistent with a role for the promoter repeat region in partially molding social behavior in both animals and humans. This is the first report in humans demonstrating a role of the AVPR1a gene in contributing to the PPI response to auditory stimuli.

  7. Neuron-derived orphan receptor 1 promoted human pulmonary artery smooth muscle cells proliferation.

    PubMed

    Wang, Chang-Guo; Lei, Wei; Li, Chang; Zeng, Da-Xiong; Huang, Jian-An

    2015-05-01

    As a transcription factor of the nuclear receptor superfamily, neuron-derived orphan receptor 1 (NOR1) is induced rapidly in response to various extracellular stimuli. But, it is still unclear its role in pulmonary artery smooth muscle cells proliferation. Human PASMCs were cultured in vitro and stimulated by serum. The special antisense oligodeoxynucleotides (AS-ODNs) were used to knockdown human NOR1 gene expression. Real-time PCR and Western-blot were used to evaluate the gene expression and protein levels. Fetal bovine serum (FBS) induced human PASMCs proliferation in a dose dependent manner. Furthermore, FBS promoted NOR1 gene expression in a dose dependent manner and a time dependent manner. 10% FBS induced a maximal NOR1 mRNA levels at 2 h. FBS also induced a significant higher NOR1 protein levels as compared with control. The NOR1 over-expressed plasmid significantly promoted DNA synthesis and cells proliferation. Moreover, the special AS-ODNs against human NOR1 not only prevented NOR1 expression but also inhibited DNA synthesis and cells proliferation significantly. The NOR1 over-expression plasmid could up-regulate cyclin D1 expression markedly, but the AS-ODNs inhibited cyclin D1 expression significantly. So, we concluded that NOR1 could promote human PASMCs proliferation. Cyclin D1 might be involved in this process.

  8. Estrogen promotes megakaryocyte polyploidization via estrogen receptor beta-mediated transcription of GATA1.

    PubMed

    Du, C; Xu, Y; Yang, K; Chen, S; Wang, X; Wang, S; Wang, C; Shen, M; Chen, F; Chen, M; Zeng, D; Li, F; Wang, T; Wang, F; Zhao, J; Ai, G; Cheng, T; Su, Y; Wang, J

    2017-04-01

    Estrogen is reported to be involved in thrombopoiesis and the disruption of its signaling may cause myeloproliferative disease, yet the underlying mechanisms remain largely unknown. GATA-binding factor 1 (GATA1) is a key regulator of megakaryocyte (MK) differentiation and its deficiency will lead to megakaryoblastic leukemia. Here we show that estrogen can dose-dependently promote MK polyploidization and maturation via activation of estrogen receptor beta (ERβ), accompanied by a significant upregulation of GATA1. Chromatin immunoprecipitation and a dual luciferase assay demonstrate that ERβ can directly bind the promoter region of GATA1 and activate its transcription. Steroid receptor coactivator 3 (SRC3) is involved in ERβ-mediated GATA1 transcription. The deficiency of ERβ or SRC3, similar to the inhibition of GATA1, leads to the impediment of estrogen-induced MK polyploidization and platelet production. Further investigations reveal that signal transducer and activator of transcription 1 signaling pathway downstream of GATA1 has a crucial role in estrogen-induced MK polyploidization, and ERβ-mediated GATA1 upregulation subsequently enhances nuclear factor erythroid-derived 2 expression, thereby promoting proplatelet formation and platelet release. Our study provides a deep insight into the molecular mechanisms of estrogen signaling in regulating thrombopoiesis and the pathogenesis of ER deficiency-related leukemia.

  9. PON1 promoter polymorphisms contribute to PCOS susceptibility and phenotypic outcomes in Indian women.

    PubMed

    Dadachanji, Roshan; Shaikh, Nuzhat; Patil, Anushree; Shah, Nalini; Mukherjee, Srabani

    2018-06-30

    Polycystic ovary syndrome is a common endocrinopathy characterized by anovulatory infertility, hyperandrogenism, insulin resistance and oxidative stress, which predisposes affected women to reproductive and cardiometabolic complications in later life. We have investigated the association of PON1 promoter polymorphisms with PCOS susceptibility, PON1 activity and its related traits in Indian women. The genotypic and allelic frequency distribution of only -907G/C polymorphism in PON1 promoter showed significant difference between non-hyperandrogenic control and PCOS women, and was significantly associated with reduced susceptibility to PCOS, considering the recessive model. PON1 lactonase and arylesterase activities were also significantly decreased in women with PCOS compared to controls. Further, PON1 promoter polymorphisms were linked to altered insulin and testosterone levels in hyperandrogenic and non-hyperandrogenic women with PCOS. This study highlights PON1 as an important candidate gene influencing genetic pathophysiology of PCOS. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. SAV1 promotes Hippo kinase activation through antagonizing the PP2A phosphatase STRIPAK

    PubMed Central

    Osinski, Adam; Tomchick, Diana R; Brautigam, Chad A

    2017-01-01

    The Hippo pathway controls tissue growth and homeostasis through a central MST-LATS kinase cascade. The scaffold protein SAV1 promotes the activation of this kinase cascade, but the molecular mechanisms remain unknown. Here, we discover SAV1-mediated inhibition of the PP2A complex STRIPAKSLMAP as a key mechanism of MST1/2 activation. SLMAP binding to autophosphorylated MST2 linker recruits STRIPAK and promotes PP2A-mediated dephosphorylation of MST2 at the activation loop. Our structural and biochemical studies reveal that SAV1 and MST2 heterodimerize through their SARAH domains. Two SAV1–MST2 heterodimers further dimerize through SAV1 WW domains to form a heterotetramer, in which MST2 undergoes trans-autophosphorylation. SAV1 directly binds to STRIPAK and inhibits its phosphatase activity, protecting MST2 activation-loop phosphorylation. Genetic ablation of SLMAP in human cells leads to spontaneous activation of the Hippo pathway and alleviates the need for SAV1 in Hippo signaling. Thus, SAV1 promotes Hippo activation through counteracting the STRIPAKSLMAP PP2A phosphatase complex. PMID:29063833

  11. GBP3 promotes glioma cell proliferation via SQSTM1/p62-ERK1/2 axis.

    PubMed

    Xu, Hui; Sun, Lili; Zheng, Yanwen; Yu, Shuye; Ou-Yang, Jia; Han, Hui; Dai, Xingliang; Yu, Xiaoting; Li, Ming; Lan, Qing

    2018-01-01

    Guanylate binding proteins (GBPs) are interferon-inducible large GTPases and play a crucial role in cell-autonomous immunity. However, the biology function of GBPs in cancer remains elusive. GBP3 is specifically expressed in adult brain. Here we show that GBP3 is highly elevated in human glioma tumors and glioma cell lines. Overexpression of GBP3 dramatically increased glioma cell proliferation whereas silencing GBP3 by RNA interference produced opposite effects. We further showed that GBP3 expression was able to induce sequestosome-1(SQSTM1, also named p62) expression and activate extracellular signal-regulated kinase (ERK1/2). The SQSTM1-ERK1/2 signaling cascade was essential for GBP3-promoted cell growth because depletion of SQSTM1 markedly reduced the phosphorylated ERK1/2 levels and GBP3-mediated cell growth, and inhibition of mitogen-activated protein kinase/ERK kinase abolished GBP3-induced glioma cell proliferation. Consistently, GBP3 overexpression significantly promoted glioma tumor growth in vivo and its expression was inversely correlated with the survival rate of glioma patients. Taken together, these results for the first time suggest that GBP3 contributes to the proliferation of glioma cells via regulating SQSTM1-ERK1/2 pathway, and GBP3 might represent as a new potential therapeutic target against glioma. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. HIV-1 Nef-associated Factor 1 Enhances Viral Production by Interacting with CRM1 to Promote Nuclear Export of Unspliced HIV-1 gag mRNA.

    PubMed

    Ren, Xiao-Xin; Wang, Hai-Bo; Li, Chuan; Jiang, Jin-Feng; Xiong, Si-Dong; Jin, Xia; Wu, Li; Wang, Jian-Hua

    2016-02-26

    HIV-1 depends on host-cell-encoded factors to complete its life cycle. A comprehensive understanding of how HIV-1 manipulates host machineries during viral infection can facilitate the identification of host targets for antiviral drugs or gene therapy. The cellular protein Naf1 (HIV-1 Nef-associated factor 1) is a CRM1-dependent nucleo-cytoplasmic shuttling protein, and has been identified to regulate multiple receptor-mediated signal pathways in inflammation. The cytoplasm-located Naf1 can inhibit NF-κB activation through binding to A20, and the loss of Naf1 controlled NF-κB activation is associated with multiple autoimmune diseases. However, the effect of Naf1 on HIV-1 mRNA expression has not been characterized. In this study we found that the nucleus-located Naf1 could promote nuclear export of unspliced HIV-1 gag mRNA. We demonstrated that the association between Naf1 and CRM1 was required for this function as the inhibition or knockdown of CRM1 expression significantly impaired Naf1-promoted HIV-1 production. The mutation of Naf1 nuclear export signals (NESs) that account for CRM1 recruitment for nuclear export decreased Naf1 function. Additionally, the mutation of the nuclear localization signal (NLS) of Naf1 diminished its ability to promote HIV-1 production, demonstrating that the shuttling property of Naf1 is required for this function. Our results reveal a novel role of Naf1 in enhancing HIV-1 production, and provide a potential therapeutic target for controlling HIV-1 infection. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  13. Characterization of strychnine-sensitive glycine receptor in the intact frog retina: modulation by protein kinases.

    PubMed

    Salceda, Rocío; Aguirre-Ramirez, Marisela

    2005-03-01

    We studied 3H-glycine and 3H-strychnine specific binding to glycine receptor (GlyR) in intact isolated frog retinas. To avoid glycine binding to glycine uptake sites, experiments were performed at low ligand concentrations in a sodium-free medium. The binding of both radiolabeled ligands was saturated. Scatchard analysis of bound glycine and strychnine revealed a KD of 2.5 and 2.0 microM, respectively. Specific binding of glycine was displaced by beta-alanine, sarcosine, and strychnine. Strychnine binding was displaced 50% by glycine, and sarcosine. Properties of the strychnine-binding site in the GlyR were modified by sarcosine. Binding of both radioligands was considerably reduced by compounds that inhibit or activate adenylate cyclase and increased cAMP levels. A phorbol ester activator of PKC remarkably decreased glycine and strychnine binding. These results suggest modulation of GlyR in response to endogenous activation of protein kinases A and C, as well as protein phosphorylation modulating GlyR function in retina.

  14. Epigenetic Changes and Suppression of the Nuclear Factor of Activated T Cell 1 (NFATC1) Promoter in Human Lymphomas with Defects in Immunoreceptor Signaling

    PubMed Central

    Akimzhanov, Askar; Krenacs, Laszlo; Schlegel, Timm; Klein-Hessling, Stefan; Bagdi, Enikö; Stelkovics, Eva; Kondo, Eisaku; Chuvpilo, Sergei; Wilke, Philipp; Avots, Andris; Gattenlöhner, Stefan; Müller-Hermelink, Hans-Konrad; Palmetshofer, Alois; Serfling, Edgar

    2008-01-01

    The nuclear factor of activated T cell 1 (Nfatc1) locus is a common insertion site for murine tumorigenic retroviruses, suggesting a role of transcription factor NFATc1 in lymphomagenesis. Although NFATc1 is expressed in most human primary lymphocytes and mature human T- and B-cell neoplasms, we show by histochemical stainings that NFATc1 expression is suppressed in anaplastic large cell lymphomas and classical Hodgkin’s lymphomas (HLs). In HL cell lines, NFATc1 silencing correlated with a decrease in histone H3 acetylation, H3-K4 trimethylation, and Sp1 factor binding but with an increase in HP1 binding to the NFATC1 P1 promoter. Together with DNA hypermethylation of the NFATC1 P1 promoter, which we detected in all anaplastic large cell lymphoma and many HL lines, these observations reflect typical signs of transcriptional silencing. In several lymphoma lines, methylation of NFATC1 promoter DNA resulted in a “window of hypomethylation,” which is flanked by Sp1-binding sites. Together with the under-representation of Sp1 at the NFATC1 P1 promoter in HL cells, this suggests that Sp1 factors can protect P1 DNA methylation in a directional manner. Blocking immunoreceptor signaling led to NFATC1 P1 promoter silencing and to a decrease in H3 acetylation and H3-K4 methylation but not DNA methylation. This shows that histone modifications precede the DNA methylation in NFATC1 promoter silencing. PMID:18156209

  15. Characterization of a spliced variant of human IRF-3 promoter and its regulation by the transcription factor Sp1.

    PubMed

    Ren, Wei; Zhu, Liang-Hua; Xu, Hua-Guo; Jin, Rui; Zhou, Guo-Ping

    2012-06-01

    Interferon regulatory factor 3 (IRF-3), an essential transcriptional regulator of the interferon genes, plays an important role in host defense against viral and microbial infection as well as in cell growth regulation. Promoter plays a crucial role in gene transcription. We have reported the characterization of the wide type of human IRF-3 promoter, but the characterization of the spliced variant of human IRF-3 Int2V1 promoter has not been systematically analyzed. To observe the spliced variant of human IRF-3 promoter, we have cloned the human IRF-3 gene promoter region containing 300 nucleotides upstream the transcription start site (TSS). Transient transfection of 5' deleted promoter-reporter constructs and luciferase assay illustrated the region -159/-100 relative to the TSS is sufficient for full promoter activity. This region contains GATA1 and specific protein-1 (Sp1) transcription factor binding sites. Interestingly, mutation of this Sp1 site reduced the promoter activity by 50%. However, overexpression of Sp1 increased the transcription activity by 2.4-fold. These results indicated that the spliced variant of human IRF-3 gene core promoter was located within the region -159/-100 relative to the TSS. Sp1 transcription factor upregulates the spliced variant of human IRF-3 gene promoter.

  16. CRHR1 promoter hypomethylation: An epigenetic readout of panic disorder?

    PubMed

    Schartner, Christoph; Ziegler, Christiane; Schiele, Miriam A; Kollert, Leonie; Weber, Heike; Zwanzger, Peter; Arolt, Volker; Pauli, Paul; Deckert, Jürgen; Reif, Andreas; Domschke, Katharina

    2017-04-01

    The corticotropin releasing hormone receptor 1 (CRHR1) is crucially involved in the hypothalamic-pituitary-adrenal axis and thus a major regulator of the stress response. CRHR1 gene variation is associated with several mental disorders including anxiety disorders. Studies in rodents have demonstrated epigenetic regulation of CRHR1 gene expression to moderate response to stressful environment. In the present study, we investigated CRHR1 promoter methylation for the first time regarding its role in panic disorder applying a case-control approach (N=131 patients, N=131 controls). In an independent sample of healthy volunteers (N=255), CRHR1 methylation was additionally analyzed for association with the Beck Anxiety Inventory (BAI) score as a dimensional panic-related intermediate phenotype. The functional relevance of altered CRHR1 promoter methylation was investigated by means of luciferase-based reporter gene assays. In panic disorder patients, a significantly decreased CRHR1 methylation was discerned (p<0.001). Accordingly, healthy controls with high BAI scores showed significantly decreased CRHR1 methylation. Functional analyses revealed an increased gene expression in presence of unmethylated as compared to methylated pCpGl_CRHR1 reporter gene vectors. The present study identified a potential role of CRHR1 hypomethylation - conferring increased CRHR1 expression - in panic disorder and a related dimensional intermediate phenotype. This up-regulation of CRHR1 gene expression driven by de-methylation might constitute a link between the stress response and panic disorder risk. Copyright © 2017 Elsevier B.V. and ECNP. All rights reserved.

  17. The necrosome promotes pancreatic oncogenesis via CXCL1 and Mincle-induced immune suppression.

    PubMed

    Seifert, Lena; Werba, Gregor; Tiwari, Shaun; Giao Ly, Nancy Ngoc; Alothman, Sara; Alqunaibit, Dalia; Avanzi, Antonina; Barilla, Rocky; Daley, Donnele; Greco, Stephanie H; Torres-Hernandez, Alejandro; Pergamo, Matthew; Ochi, Atsuo; Zambirinis, Constantinos P; Pansari, Mridul; Rendon, Mauricio; Tippens, Daniel; Hundeyin, Mautin; Mani, Vishnu R; Hajdu, Cristina; Engle, Dannielle; Miller, George

    2016-04-14

    Neoplastic pancreatic epithelial cells are believed to die through caspase 8-dependent apoptotic cell death, and chemotherapy is thought to promote tumour apoptosis. Conversely, cancer cells often disrupt apoptosis to survive. Another type of programmed cell death is necroptosis (programmed necrosis), but its role in pancreatic ductal adenocarcinoma (PDA) is unclear. There are many potential inducers of necroptosis in PDA, including ligation of tumour necrosis factor receptor 1 (TNFR1), CD95, TNF-related apoptosis-inducing ligand (TRAIL) receptors, Toll-like receptors, reactive oxygen species, and chemotherapeutic drugs. Here we report that the principal components of the necrosome, receptor-interacting protein (RIP)1 and RIP3, are highly expressed in PDA and are further upregulated by the chemotherapy drug gemcitabine. Blockade of the necrosome in vitro promoted cancer cell proliferation and induced an aggressive oncogenic phenotype. By contrast, in vivo deletion of RIP3 or inhibition of RIP1 protected against oncogenic progression in mice and was associated with the development of a highly immunogenic myeloid and T cell infiltrate. The immune-suppressive tumour microenvironment associated with intact RIP1/RIP3 signalling depended in part on necroptosis-induced expression of the chemokine attractant CXCL1, and CXCL1 blockade protected against PDA. Moreover, cytoplasmic SAP130 (a subunit of the histone deacetylase complex) was expressed in PDA in a RIP1/RIP3-dependent manner, and Mincle--its cognate receptor--was upregulated in tumour-infiltrating myeloid cells. Ligation of Mincle by SAP130 promoted oncogenesis, whereas deletion of Mincle protected against oncogenesis and phenocopied the immunogenic reprogramming of the tumour microenvironment that was induced by RIP3 deletion. Cellular depletion suggested that whereas inhibitory macrophages promote tumorigenesis in PDA, they lose their immune-suppressive effects when RIP3 or Mincle is deleted. Accordingly, T cells

  18. Phosphorylation of Nanog is Essential to Regulate Bmi1 and Promote Tumorigenesis

    PubMed Central

    Xie, Xiujie; Piao, Longzhu; Cavey, Greg S.; Old, Matthew; Teknos, Theodoros N.; Mapp, Anna K; Pan, Quintin

    2014-01-01

    Emerging evidence indicates that Nanog is intimately involved in tumorigenesis in part through regulation of the cancer initiating cell population. However, the regulation and role of Nanog in tumorigenesis are still poorly understood. In this study, human Nanog was identified to be phosphorylated by human PKCε at multiple residues including T200 and T280. Our work indicated that phosphorylation at T200 and T280 modulates Nanog function through several regulatory mechanisms. Results with phosphorylation-insensitive and phosphorylation-mimetic mutant Nanog revealed that phosphorylation at T200 and T280 enhance Nanog protein stability. Moreover, phosphorylation-insensitive T200A and T280A mutant Nanog had a dominant-negative function to inhibit endogenous Nanog transcriptional activity. Inactivation of Nanog was due to impaired homodimerization, DNA binding, promoter occupancy, and p300, a transcriptional co-activator, recruitment resulting in a defect in target gene promoter activation. Ectopic expression of phosphorylation-insensitive T200A or T280A mutant Nanog reduced cell proliferation, colony formation, invasion, migration, and the cancer initiating cell population in head and neck squamous cell carcinoma (HNSCC) cells. The in vivo cancer initiating ability was severely compromised in HNSCC cells expressing phosphorylation-insensitive T200A or T280A mutant Nanog; 87.5% (14/16), 12.5% (1/8), and 0% (0/8) for control, T200A, and T280A, respectively. Nanog occupied the Bmi1 promoter to directly transactivate and regulate Bmi1. Genetic ablation and rescue experiments demonstrated that Bmi1 is a critical downstream signaling node for the pleiotropic, pro-oncogenic effects of Nanog. Taken together, our study revealed, for the first time, that post-translational phosphorylation of Nanog is essential to regulate Bmi1 and promote tumorigenesis. PMID:23708658

  19. Interaction of the Transcription Start Site Core Region and Transcription Factor YY1 Determine Ascorbate Transporter SVCT2 Exon 1a Promoter Activity

    PubMed Central

    Qiao, Huan; May, James M.

    2012-01-01

    Transcription of the ascorbate transporter, SVCT2, is driven by two distinct promoters in exon 1 of the transporter sequence. The exon 1a promoter lacks a classical transcription start site and little is known about regulation of promoter activity in the transcription start site core (TSSC) region. Here we present evidence that the TSSC binds the multifunctional initiator-binding protein YY1. Electrophoresis shift assays using YY1 antibody showed that YY1 is present as one of two major complexes that specifically bind to the TSSC. The other complex contains the transcription factor NF-Y. Mutations in the TSSC that decreased YY1 binding also impaired the exon 1a promoter activity despite the presence of an upstream activating NF-Y/USF complex, suggesting that YY1 is involved in the regulation of the exon 1a transcription. Furthermore, YY1 interaction with NF-Y and/or USF synergistically enhanced the exon 1a promoter activity in transient transfections and co-activator p300 enhanced their synergistic activation. We propose that the TSSC plays a vital role in the exon 1a transcription and that this function is partially carried out by the transcription factor YY1. Moreover, co-activator p300 might be able to synergistically enhance the TSSC function via a “bridge” mechanism with upstream sequences. PMID:22532872

  20. The promoter of the pepper pathogen-induced membrane protein gene CaPIMP1 mediates environmental stress responses in plants.

    PubMed

    Hong, Jeum Kyu; Hwang, Byung Kook

    2009-01-01

    The promoter of the pepper pathogen-induced membrane protein gene CaPIMP1 was analyzed by an Agrobacterium-mediated transient expression assay in tobacco leaves. Several stress-related cis-acting elements (GT-1, W-box and ABRE) are located within the CaPIMP1 promoter. In tobacco leaf tissues transiently transformed with a CaPIMP1 promoter-beta-glucuronidase (GUS) gene fusion, serially 5'-deleted CaPIMP1 promoters were differentially activated by Pseudomonas syringae pv. tabaci, ethylene, methyl jasmonate, abscisic acid, and nitric oxide. The -1,193 bp region of the CaPIMP1 gene promoter sequence exhibited full promoter activity. The -417- and -593 bp promoter regions were sufficient for GUS gene activation by ethylene and methyl jasmonate treatments, respectively. However, CaPIMP1 promoter sequences longer than -793 bp were required for promoter activation by abscisic acid and sodium nitroprusside treatments. CaPIMP1 expression was activated in pepper leaves by treatment with ethylene, methyl jasmonate, abscisic acid, beta-amino-n-butyric acid, NaCl, mechanical wounding, and low temperature, but not with salicylic acid. Overexpression of CaPIMP1 in Arabidopsis conferred hypersensitivity to mannitol, NaCl, and ABA during seed germination but not during seedling development. In contrast, transgenic plants overexpressing CaPIMP1 exhibited enhanced tolerance to oxidative stress induced by methyl viologen during germination and early seedling stages. These results suggest that CaPIMP1 expression may alter responsiveness to environmental stress, as well as to pathogen infection.

  1. Inhibition of the binding of MSG-intermolt-specific complex, MIC, to the sericin-1 gene promoter and sericin-1 gene expression by POU-M1/SGF-3.

    PubMed

    Kimoto, Mai; Kitagawa, Tsuyuki; Kobayashi, Isao; Nakata, Tomohiro; Kuroiwa, Asato; Takiya, Shigeharu

    2012-11-01

    The sericin-1 gene encoding a glue protein is expressed in the middle silk gland (MSG) of the silkworm, Bombyx mori. A member of the class III POU domain transcription factors, POU-M1, was cloned as the factor bound to the SC site of the sericin-1 promoter and has been proposed to be a positive transcription factor. In this study, we analyzed the expression pattern of the POU-M1 gene in fourth and fifth instars in comparison with the pattern of the sericin-1 gene. The POU-M1 gene was expressed strongly in the region anterior to the sericin-1-expressing portion of the silk gland at both feeding stages. As the sericin-1-expressing region expands from the posterior to middle portions of the MSG in the fifth instar, the POU-M1-expressing region retreated from the middle to anterior portion. Introduction of the expression vector of POU-M1 into the silk glands by gene gun technology repressed promoter activity of the sericin-1 gene, suggesting that POU-M1 regulates the sericin-1 gene negatively. An in vitro binding assay showed that POU-M1 bound not only to the SC site but also to other promoter elements newly detected in vivo. Another spatiotemporal specific factor MIC binds to these elements, and POU-M1 competed with MIC to bind at the -70 site essential for promoter activity. These results suggest that POU-M1 is involved in restricting the anterior boundary of the sericin-1-expressing region in the silk gland by inhibiting the binding of the transcriptional activator to the promoter elements.

  2. Evaluation of promoter methylation status of MLH1 gene in Iranian patients with colorectal tumors and adenoma polyps.

    PubMed

    Zarandi, Ashkan; Irani, Shiva; Savabkar, Sanaz; Chaleshi, Vahid; Ghavideldarestani, Maryam; Mirfakhraie, Reza; Khodadoostan, Mahsa; Nazemalhosseini-Mojarad, Ehsan; Asadzadeh Aghdaei, Hamid

    2017-01-01

    The aim of this study was to evaluate the methylation status of the promoter region of MLH1 gene in colorectal cancer (CRC) and its precursor lesions as well as elucidate its association with various clinicopathological characteristics among Iranian population. Epigenetic silencing of mismatch repair genes, such as MLH1 , by methylation of CpG islands of their promoter region has been proved to be an important mechanism in colorectal carcinogenesis. Fifty colorectal cancer and polyp tissue samples including 13 Primary colorectal tumor and 37 Adenoma polyp samples were enrolled in this study. Methylation-specific polymerase chain reaction (MSP) was performed to find the frequency of MLH1 Promoter Methylation. Promoter methylation of MLH1 gene was detected in 5 out of 13 tumor tissues and 4 out of 37 adenoma polyp. The frequency of MLH1 methylation in tumor samples was significantly higher compared to that in polyp tissues (P= 0.026). No significant association was observed between MLH1 promoter methylation and clinicopathological characteristics of the patients. The frequency of  MLH1  promoter methylation in CRC and colon polyp was 18%. Our findings indicated that methylation of MLH1 promoter region alone cannot be considered as a biomarker for early detection of CRC.

  3. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Moussa, Sana Ben; Bachouâ, Hassen; Gruselle, Michel, E-mail: michel.gruselle@upmc.fr

    The present article details the formation of calcium hydroxyapatite synthesized by the hydrothermal way, in presence of glycine or sarcosine. The presence of these amino-acids during the synthetic processes reduces the crystalline growthing through the formation of hybrid organic-inorganic species The crystallite sizes are decreasing and the morphology is modified with the increase of the amino-acid concentration. - Graphical abstract: Formation of Ca carboxylate salt leading to the grafting of glycine and sarcosine on the Ca=Hap surface (R= H, CH3).

  4. Mutant IDH1 expression drives TERT promoter reactivation as part of the cellular transformation process

    PubMed Central

    Ohba, Shigeo; Mukherjee, Joydeep; Johannessen, Tor-Christian; Mancini, Andrew; Chow, Tracy T.; Wood, Matthew; Jones, Lindsey; Mazor, Tali; Marshall, Roxanne E.; Viswanath, Pavithra; Walsh, Kyle M.; Perry, Arie; Bell, Robert J. A.; Phillips, Joanna J.; Costello, Joseph F.; Ronen, Sabrina M.; Pieper, Russell O.

    2016-01-01

    Mutations in the isocitrate dehydrogenase gene IDH1 are common in lower-grade glioma where they result in the production of 2-hydroxyglutarate (2HG), disrupted patterns of histone methylation and gliomagenesis. IDH1 mutations also co-segregate with mutations in the ATRX gene and the TERT promoter, suggesting that IDH mutation may drive the creation or selection of telomere-stabilizing events as part of immortalization/transformation process. To determine if and how this may occur, we investigated the phenotype of pRb/p53-deficient human astrocytes engineered with IDH1 wild-type (WT) or R132H mutant (IDH1mut) genes as they progressed through their lifespan. IDH1mut expression promoted 2HG production and altered histone methylation within 20 population doublings (PD), but had no effect on telomerase expression or telomere length. Accordingly, cells expressing either IDH1 WT or IDH1mut entered a telomere-induced crisis at PD 70. In contrast, only IDH1mut cells emerged from crisis, grew indefinitely in culture and formed colonies in soft agar and tumors in vivo. Clonal populations of post-crisis IDH1mut cells displayed shared genetic alterations, but no mutations in ATRX or the TERT promoter were detected. Instead, these cells reactivated telomerase and stabilized their telomeres in association with increased histone lysine methylation (H3K4me3) and c-Myc/Max binding at the TERT promoter. Overall, these results show that while IDH1mut does not create or select for ATRX or TERT promoter mutations, it can indirectly reactivate TERT, and in doing so contribute to astrocytic immortalization and transformation. PMID:27758882

  5. DNA Methylation in the Neuropeptide S Receptor 1 (NPSR1) Promoter in Relation to Asthma and Environmental Factors

    PubMed Central

    Reinius, Lovisa E.; Gref, Anna; Sääf, Annika; Acevedo, Nathalie; Joerink, Maaike; Kupczyk, Maciej; D'Amato, Mauro; Bergström, Anna; Melén, Erik; Scheynius, Annika; Dahlén, Sven-Erik; Pershagen, Göran; Söderhäll, Cilla; Kere, Juha

    2013-01-01

    Asthma and allergy are complex disorders influenced by both inheritance and environment, a relationship that might be further clarified by epigenetics. Neuropeptide S Receptor 1 (NPSR1) has been associated with asthma and allergy and a study suggested modulation of the genetic risk by environmental factors. We aimed to study DNA methylation in the promoter region of NPSR1 in relation to asthma and environmental exposures. Electrophoretic Mobility Shift Assay (EMSA) was used to investigate potential functional roles of both genotypes and methylation status in the NPSR1 promoter. DNA methylation was analysed using EpiTYPER in blood samples from two well-characterized cohorts; the BIOAIR study of severe asthma in adults and the Swedish birth cohort BAMSE. We observed that DNA methylation and genetic variants in the promoter influenced the binding of nuclear proteins to DNA, suggesting functional relevance. Significant, although small, differences in methylation were related to both adult severe asthma (p = 0.0001) and childhood allergic asthma (p = 0.01). Furthermore, DNA methylation was associated with exposures such as current smoking in adults for two CpG sites (p = 0.005 and 0.04), parental smoking during infancy in the children (p = 0.02) and in which month the sample was taken (p = 0.01). In summary, DNA methylation levels in the promoter of NPSR1 showed small but significant associations with asthma, both in adults and in children, and to related traits such as allergy and certain environmental exposures. Both genetic variation and the methylated state of CpG sites seem to have an effect on the binding of nuclear proteins in the regulatory region of NPSR1 suggesting complex regulation of this gene in asthma and allergy. PMID:23372674

  6. Repression of Virus-Induced Interferon A Promoters by Homeodomain Transcription Factor Ptx1

    PubMed Central

    Lopez, Sébastien; Island, Marie-Laure; Drouin, Jacques; Bandu, Marie-Thérese; Christeff, Nicolas; Darracq, Nicole; Barbey, Régine; Doly, Janine; Thomas, Dominique; Navarro, Sébastien

    2000-01-01

    Interferon A (IFN-A) genes are differentially expressed after virus induction. The differential expression of individual IFN-A genes is modulated by substitutions in the proximal positive virus responsive element A (VRE-A) of their promoters and by the presence or absence of a distal negative regulatory element (DNRE). The functional feature of the DNRE is to specifically act by repression of VRE-A activity. With the use of the yeast one-hybrid system, we describe here the identification of a specific DNRE-binding protein, the pituitary homeobox 1 (Ptx1 or Pitx1). Ptx1 is detectable in different cell types that differentially express IFN-A genes, and the endogenous Ptx1 protein binds specifically to the DNRE. Upon virus induction, Ptx1 negatively regulates the transcription of DNRE-containing IFN-A promoters, and the C-terminal region, as well as the homeodomain of the Ptx1 protein, is required for this repression. After virus induction, the expression of the Ptx1 antisense RNA leads to a significant increase of endogenous IFN-A gene transcription and is able to modify the pattern of differential expression of individual IFN-A genes. These studies suggest that Ptx1 contributes to the differential transcriptional strength of the promoters of different IFN-A genes and that these genes may provide new targets for transcriptional regulation by a homeodomain transcription factor. PMID:11003649

  7. Bisphenol A promotes cholesterol absorption in Caco-2 cells by up-regulation of NPC1L1 expression.

    PubMed

    Feng, Dan; Zou, Jun; Zhang, Shanshan; Li, Xuechun; Li, Peiyang; Lu, Minqi

    2017-01-06

    Bisphenol A (BPA), an commonly exposed environmental chemicals in humans, has been shown to have a hypercholesterolemic effect with molecular mechanism not clear. Since intestinal cholesterol absorption plays a major role in maintaining total body cholesterol homeostasis, the present study is to investigate whether BPA affects cholesterol absorption in the intestinal Caco-2 cells. The Caco-2 cells were pretreated with BPA at different concentrations for 24 h and then incubated with radioactive micellar cholesterol for 2 h. The absorption of radioactive cholesterol was quantified by liquid scintillation. The expression of Niemann-Pick C1-like 1 (NPC1L1) and sterol regulatory element binding protein-2 (SREBP-2) was analyzed by Western blot and qPCR. We found that confluent Caco-2 cells expressed NPC1L1, and the absorption of cholesterol in the cells was inhibited by ezetimibe, a specific inhibitor of NPC1L1. We then pretreated the cells with 0.1-10 nM BPA for 24 h and found that BPA at 1 and 10 nM doses promoted cholesterol absorption. In addition, we found that the BPA-induced promotion of cholesterol absorption was associated with significant increase in the levels of NPC1L1 protein and NPC1L1 mRNA. Moreover, the stimulatory effects of BPA on cholesterol absorption and NPC1L1 expression could be prevented by blockade of the SREBP-2 pathway. This study provides the first evidence that BPA promotes cholesterol absorption in the intestinal cells and the stimulatory effect of BPA is mediated, at least in part, by SREBP-2-NPC1L1 signaling pathway.

  8. STMN1 Promotes Progesterone Production Via StAR Up-regulation in Mouse Granulosa Cells.

    PubMed

    Dou, Yun-De; Zhao, Han; Huang, Tao; Zhao, Shi-Gang; Liu, Xiao-Man; Yu, Xiao-Chen; Ma, Zeng-Xiang; Zhang, Yu-Chao; Liu, Tao; Gao, Xuan; Li, Lei; Lu, Gang; Chan, Wai-Yee; Gao, Fei; Liu, Hong-Bin; Chen, Zi-Jiang

    2016-06-08

    Stathmin 1 (STMN1) is a biomarker in several types of neoplasms. It plays an important role in cell cycle progression, mitosis, signal transduction and cell migration. In ovaries, STMN1 is predominantly expressed in granulosa cells (GCs). However, little is known about the role of STMN1 in ovary. In this study, we demonstrated that STMN1 is overexpressed in GCs in patients with polycystic ovary syndrome (PCOS). In mouse primary GCs, the overexpression of STMN1 stimulated progesterone production, whereas knockdown of STMN1 decreased progesterone production. We also found that STMN1 positively regulates the expression of Star (steroidogenic acute regulatory protein) and Cyp11a1 (cytochrome P450 family 11 subfamily A member 1). Promoter and ChIP assays indicated that STMN1 increased the transcriptional activity of Star and Cyp11a1 by binding to their promoter regions. The data suggest that STMN1 mediates the progesterone production by modulating the promoter activity of Star and Cyp11a1. Together, our findings provide novel insights into the molecular mechanisms of STMN1 in ovary GC steroidogenesis. A better understanding of this potential interaction between STMN1 and Star in progesterone biosynthesis in GCs will facilitate the discovery of new therapeutic targets in PCOS.

  9. DIXDC1 activates the Wnt signaling pathway and promotes gastric cancer cell invasion and metastasis.

    PubMed

    Tan, Cong; Qiao, Fan; Wei, Ping; Chi, Yayun; Wang, Weige; Ni, Shujuan; Wang, Qifeng; Chen, Tongzhen; Sheng, Weiqi; Du, Xiang; Wang, Lei

    2016-04-01

    DIXDC1 (Dishevelled-Axin domain containing 1) is a DIX (Dishevelled-Axin) domain-possessing protein that promotes colon cancer cell proliferation and increases the invasion and migration ability of non-small-cell lung cancer via the PI3K pathway. As a positive regulator of the Wnt/β-catenin pathway, the biological role of DIXDC1 in human gastric cancer and the relationship between DIXDC1 and the Wnt pathway are unclear. In the current study, the upregulation of DIXDC1 was detected in gastric cancer and was associated with advanced TNM stage cancer, lymph node metastasis, and poor prognosis. We also found that the overexpression of DIXDC1 could promote the invasion and migration of gastric cancer cells. The upregulation of MMPs and the downregulation of E-cadherin were found to be involved in the process. DIXDC1 enhanced β-catenin nuclear accumulation, which activated the Wnt pathway. Additionally, the inhibition of β-catenin in DIXDC1-overexpressing cells reversed the metastasis promotion effects of DIXDC1. These results demonstrate that the expression of DIXDC1 is associated with poor prognosis of gastric cancer patients and that DIXDC1 promotes gastric cancer invasion and metastasis through the activation of the Wnt pathway; E-cadherin and MMPs are also involved in this process. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

  10. The human luteinizing hormone receptor gene promoter: activation by Sp1 and Sp3 and inhibitory regulation.

    PubMed

    Geng, Y; Tsai-Morris, C H; Zhang, Y; Dufau, M L

    1999-09-24

    To understand the transcriptional mechanism(s) of human LH receptor (LHR) gene expression, we have identified the dominant functional cis-elements that regulate the activity of the promoter domain (-1 to -176 bp from ATG). Mutagenesis demonstrated that the promoter activity was dependent on two Sp1 domains (-79 bp, -120 bp) in a transformed normal placental cell (PLC) and the choriocarcinoma JAR cell. Both elements interacted with endogenous Sp1 and Sp3 factors but not with Sp2 or Sp4. In Drosophila SL2 cells, the promoter was activated by either Sp1 or Sp3. An ERE half-site (EREhs) at -174 bp was inhibitory (by 100%), but was unresponsive to estradiol and did not bind the estrogen receptor or orphan receptors ERR1 and SF-1. The 5' upstream sequence (-177 to -2056 bp) inhibited promoter activity in PLC by 60%, but only minimally in JAR cells. Activation of the human LHR promoter through Sp1/3 factors is negatively regulated through EREhs and upstream sequences to exert control of gene expression. Copyright 1999 Academic Press.

  11. [Interactions of 1A2 insulator with promoter of hsp 70 gene in Drosophila melanogaster].

    PubMed

    Chetverina, D A; Elizar'ev, P V; Georgiev, P G; Erokhin, M M

    2013-04-01

    Insulators are regulatory DNA elements that participate in the modulation of the interactions between enhancers and promoters. Depending on the situation, insulators can either stabilize or destroy the contacts between enhancers and promoters. A possible explanation for the activity of insulators is their ability to directly interact with gene promoters. In the present study, it was demonstrated that, in model systems, a 1A2 insulator could interact with the core sequence of an hsp70 promoter. In this case, the insulator protein CP190 is found on the hsp70 promoter, which depends on the presence of an insulator in the transgene. The data obtained are consistent with the model, which implies that direct contacts between insulators and promoters make a considerable contribution to the modulation of the interactions between insulators and promoters.

  12. Metastasis-associated in colon cancer-1 promotes vasculogenic mimicry in gastric cancer by upregulating TWIST1/2

    PubMed Central

    Wang, Lin; Lin, Li; Chen, Xi; Sun, Li; Liao, Yulin; Huang, Na; Liao, Wangjun

    2015-01-01

    Vasculogenic mimicry (VM) is a blood supply modality that is strongly associated with the epithelial-mesenchymal transition (EMT), TWIST1 activation and tumor progression. We previously reported that metastasis-associated in colon cancer-1 (MACC1) induced the EMT and was associated with a poor prognosis of patients with gastric cancer (GC), but it remains unknown whether MACC1 promotes VM and regulates the TWIST signaling pathway in GC. In this study, we investigated MACC1 expression and VM by immunohistochemistry in 88 patients with stage IV GC, and also investigated the role of TWIST1 and TWIST2 in MACC1-induced VM by using nude mice with GC xenografts and GC cell lines. We found that the VM density was significantly increased in the tumors of patients who died of GC and was positively correlated with MACC1 immunoreactivity (p < 0.05). The 3-year survival rate was only 8.6% in patients whose tumors showed double positive staining for MACC1 and VM, whereas it was 41.7% in patients whose tumors were negative for both MACC1 and VM. Moreover, nuclear expression of MACC1, TWIST1, and TWIST2 was upregulated in GC tissues compared with matched adjacent non-tumorous tissues (p < 0.05). Overexpression of MACC1 increased TWIST1/2 expression and induced typical VM in the GC xenografts of nude mice and in GC cell lines. MACC1 enhanced TWIST1/2 promoter activity and facilitated VM, while silencing of TWIST1 or TWIST2 inhibited VM. Hepatocyte growth factor (HGF) increased the nuclear translocation of MACC1, TWIST1, and TWIST2, while a c-Met inhibitor reduced these effects. These findings indicate that MACC1 promotes VM in GC by regulating the HGF/c-Met-TWIST1/2 signaling pathway, which means that MACC1 and this pathway are potential new therapeutic targets for GC. PMID:25895023

  13. Involvement of Sp1 elements in the promoter activity of genes affected in keratoconus.

    PubMed

    Maruyama, Y; Wang, X; Li, Y; Sugar, J; Yue, B Y

    2001-08-01

    Keratoconus is a progressive disease that thins and scars the corneal stroma. In keratoconus corneas, levels of degradative enzymes, including lysosomal acid phosphatase (LAP) and cathepsin B, are elevated, and those of the inhibitors alpha1-proteinase inhibitor (alpha 1-PI) and alpha 2-macroglobulin (alpha 2-M) are reduced, especially in the epithelial layer. An increased expression of the transcription factor Sp1 was also demonstrated. The role of Sp1 in regulation of the genes affected in keratoconus was examined in this study. DNA segments, containing 5'-flanking promoter sequences of the alpha 1-PI, LAP, cathepsin B, and alpha 2-M genes were ligated into the secreted alkaline phosphatase (SEAP) reporter gene vector. These constructs, along with the pSV beta-galactosidase control vector, were transfected into cultured human corneal epithelial and stromal cells and skin fibroblasts. Cotransfection with the Sp1 expression vector was performed in parallel. SEAP and beta-galactosidase enzyme activities were assayed. In corneal epithelial cells, as in stromal cells, alpha 1-PI promoter activity was suppressed by cotransfection of pPacSp1. The LAP, cathepsin B, and alpha 2-M promoters were functional in corneal cells, whereas activities of these promoters were much lower in skin fibroblasts. Cotransfection experiments indicated that the up- or downregulation of LAP, cathepsin B, and alpha 2-M observed in keratoconus-affected corneas was not mediated by Sp1. These results support the theory that the corneal epithelium, along with the stroma, is involved in keratoconus. An upstream role of Sp1 is indicated and the Sp1-mediated downregulation of the alpha 1-PI gene may be a key event in the disease development.

  14. Effects of an orally active vasopressin V1 receptor antagonist.

    PubMed

    Burrell, L M; Phillips, P A; Stephenson, J; Risvanis, J; Hutchins, A M; Johnston, C I

    1993-05-01

    1. This paper reports on the in vitro and in vivo characteristics of a non-peptide vasopressin V1 receptor antagonist 1-(1-[4-(3-acetylaminopropoxy)benzoyl]-4-piperidyl)-3,4-dihydro-2( 1H)- quinolinone (OPC-21268). 2. OPC-21268 caused a concentration-dependent displacement of the selective V1 receptor antagonist radioligand, [125I]-[d(CH2)5, sarcosine7]AVP from vasopressin V1 receptors in rat liver and kidney membranes, inhibitory concentration of 50% (IC50) 4 x 10(-8), 0.3 mol/L liver and 1.5 x 10(-8), 0.2 mol/L kidney. OPC-21268 had little effect on the selective V2 antagonist radioligand [3H]desGly-NH2(9)-d(CH2)5[D-Ileu2, Ileu4]AVP binding to V2 receptors in renal membranes (IC50 > 10(-4) mol/L). 3. After oral administration to rats, OPC-21268 was an effective V1 antagonist to both liver and kidney V1 receptors, in a dose-dependent manner. 4. These studies confirm that OPC-21268 is a potent non-peptide, orally effective V1 vasopressin receptor antagonist.

  15. SAV1 promotes Hippo kinase activation through antagonizing the PP2A phosphatase STRIPAK

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bae, Sung Jun; Ni, Lisheng; Osinski, Adam

    The Hippo pathway controls tissue growth and homeostasis through a central MST-LATS kinase cascade. The scaffold protein SAV1 promotes the activation of this kinase cascade, but the molecular mechanisms remain unknown. Here, we discover SAV1-mediated inhibition of the PP2A complex STRIPAKSLMAP as a key mechanism of MST1/2 activation. SLMAP binding to autophosphorylated MST2 linker recruits STRIPAK and promotes PP2A-mediated dephosphorylation of MST2 at the activation loop. Our structural and biochemical studies reveal that SAV1 and MST2 heterodimerize through their SARAH domains. Two SAV1–MST2 heterodimers further dimerize through SAV1 WW domains to form a heterotetramer, in which MST2 undergoes trans-autophosphorylation. SAV1more » directly binds to STRIPAK and inhibits its phosphatase activity, protecting MST2 activation-loop phosphorylation. Genetic ablation of SLMAP in human cells leads to spontaneous activation of the Hippo pathway and alleviates the need for SAV1 in Hippo signaling. Thus, SAV1 promotes Hippo activation through counteracting the STRIPAKSLMAP PP2A phosphatase complex.« less

  16. INHIBITION OF INDUCED DIFFERENTIATION OF C3H/1OT 1/2 CLONE 8 MOUSE EMBRYO CELLS BY TUMOR PROMOTERS

    EPA Science Inventory

    C3H/10T 1/2 cells were induced to differentiate into muscle cells by treatment with 5-azacytidine, and the effects of tumor promoters, nonpromoters, and inhibitors of tumor promotion on this induced differentiation were investigated. Cell morphology was dramatically changed withi...

  17. Tissue- and agonist-specific regulation of human and murine plasminogen activator inhibitor-1 promoters in transgenic mice.

    PubMed

    Eren, M; Painter, C A; Gleaves, L A; Schoenhard, J A; Atkinson, J B; Brown, N J; Vaughan, D E

    2003-11-01

    Numerous studies have described regulatory factors and sequences that control transcriptional responses in vitro. However, there is a paucity of information on the qualitative and quantitative regulation of heterologous promoters using transgenic strategies. In order to investigate the physiological regulation of human plasminogen activator inhibitor type-1 (hPAI-1) expression in vivo compared to murine PAI-1 (mPAI-1) and to test the physiological relevance of regulatory mechanisms described in vitro, we generated transgenic mice expressing enhanced green fluorescent protein (EGFP) driven by the proximal -2.9 kb of the hPAI-1 promoter. Transgenic animals were treated with Ang II, TGF-beta1 and lipopolysaccharide (LPS) to compare the relative activation of the human and murine PAI-1 promoters. Ang II increased EGFP expression most effectively in brain, kidney and spleen, while mPAI-1 expression was quantitatively enhanced most prominently in heart and spleen. TGF-beta1 failed to induce activation of the hPAI-1 promoter but potently stimulated mPAI-1 in kidney and spleen. LPS administration triggered robust expression of mPAI-1 in liver, kidney, pancreas, spleen and lung, while EGFP was induced only modestly in heart and kidney. These results indicate that the transcriptional response of the endogenous mPAI-1 promoter varies widely in terms of location and magnitude of response to specific stimuli. Moreover, the physiological regulation of PAI-1 expression likely involves a complex interaction of transcription factors and DNA sequences that are not adequately replicated by in vitro functional studies focused on the proximal -2.9 kb promoter.

  18. Tax relieves transcriptional repression by promoting histone deacetylase 1 release from the human T-cell leukemia virus type 1 long terminal repeat.

    PubMed

    Lu, Hanxin; Pise-Masison, Cynthia A; Linton, Rebecca; Park, Hyeon Ung; Schiltz, R Louis; Sartorelli, Vittorio; Brady, John N

    2004-07-01

    Expression of human T-cell leukemia virus type 1 (HTLV-1) is regulated by the viral transcriptional activator Tax. Tax activates viral transcription through interaction with the cellular transcription factor CREB and the coactivators CBP/p300. In this study, we have analyzed the role of histone deacetylase 1 (HDAC1) on HTLV-1 gene expression from an integrated template. First we show that trichostatin A, an HDAC inhibitor, enhances Tax expression in HTLV-1-transformed cells. Second, using a cell line containing a single-copy HTLV-1 long terminal repeat, we demonstrate that overexpression of HDAC1 represses Tax transactivation. Furthermore, a chromatin immunoprecipitation assay allowed us to analyze the interaction of transcription factors, coactivators, and HDACs with the basal and activated HTLV-1 promoter. We demonstrate that HDAC1 is associated with the inactive, but not the Tax-transactivated, HTLV-1 promoter. In vitro and in vivo glutathione S-transferase-Tax pull-down and coimmunoprecipitation experiments demonstrated that there is a direct physical association between Tax and HDAC1. Importantly, biotinylated chromatin pull-down assays demonstrated that Tax inhibits and/or dissociates the binding of HDAC1 to the HTLV-1 promoter. Our results provide evidence that Tax interacts directly with HDAC1 and regulates binding of the repressor to the HTLV-1 promoter.

  19. The inhibition of IGF-1 signaling promotes proteostasis by enhancing protein aggregation and deposition.

    PubMed

    Moll, Lorna; Ben-Gedalya, Tziona; Reuveni, Hadas; Cohen, Ehud

    2016-04-01

    The discovery that the alteration of aging by reducing the activity of the insulin/IGF-1 signaling (IIS) cascade protects nematodes and mice from neurodegeneration-linked, toxic protein aggregation (proteotoxicity) raises the prospect that IIS inhibitors bear therapeutic potential to counter neurodegenerative diseases. Recently, we reported that NT219, a highly efficient IGF-1 signaling inhibitor, protects model worms from the aggregation of amyloid β peptide and polyglutamine peptides that are linked to the manifestation of Alzheimer's and Huntington's diseases, respectively. Here, we employed cultured cell systems to investigate whether NT219 promotes protein homeostasis (proteostasis) in mammalian cells and to explore its underlying mechanisms. We found that NT219 enhances the aggregation of misfolded prion protein and promotes its deposition in quality control compartments known as "aggresomes." NT219 also elevates the levels of certain molecular chaperones but, surprisingly, reduces proteasome activity and impairs autophagy. Our findings show that IGF-1 signaling inhibitors in general and NT219 in particular can promote proteostasis in mammalian cells by hyperaggregating hazardous proteins, thereby bearing the potential to postpone the onset and slow the progression of neurodegenerative illnesses in the elderly.-Moll, L., Ben-Gedalya, T., Reuveni, H., Cohen, E. The inhibition of IGF-1 signaling promotes proteostasis by enhancing protein aggregation and deposition. © FASEB.

  20. Mini-Term: Exploring Career Choices

    ERIC Educational Resources Information Center

    Velcich, Joann; Mitchell, Mary Ellen

    1976-01-01

    Mini-term (an out-of-school, short-term, field experience) was implemented at the University of Knoxville so students could examine the work environment and job responsibilities of a specific career. Increase in student participation and positive student comments have provided the impetus for revising the program to meet future needs. (KRP)

  1. Cysteine Dioxygenase 1 Is a Tumor Suppressor Gene Silenced by Promoter Methylation in Multiple Human Cancers

    PubMed Central

    Brait, Mariana; Ling, Shizhang; Nagpal, Jatin K.; Chang, Xiaofei; Park, Hannah Lui; Lee, Juna; Okamura, Jun; Yamashita, Keishi; Sidransky, David; Kim, Myoung Sook

    2012-01-01

    The human cysteine dioxygenase 1 (CDO1) gene is a non-heme structured, iron-containing metalloenzyme involved in the conversion of cysteine to cysteine sulfinate, and plays a key role in taurine biosynthesis. In our search for novel methylated gene promoters, we have analyzed differential RNA expression profiles of colorectal cancer (CRC) cell lines with or without treatment of 5-aza-2′-deoxycytidine. Among the genes identified, the CDO1 promoter was found to be differentially methylated in primary CRC tissues with high frequency compared to normal colon tissues. In addition, a statistically significant difference in the frequency of CDO1 promoter methylation was observed between primary normal and tumor tissues derived from breast, esophagus, lung, bladder and stomach. Downregulation of CDO1 mRNA and protein levels were observed in cancer cell lines and tumors derived from these tissue types. Expression of CDO1 was tightly controlled by promoter methylation, suggesting that promoter methylation and silencing of CDO1 may be a common event in human carcinogenesis. Moreover, forced expression of full-length CDO1 in human cancer cells markedly decreased the tumor cell growth in an in vitro cell culture and/or an in vivo mouse model, whereas knockdown of CDO1 increased cell growth in culture. Our data implicate CDO1 as a novel tumor suppressor gene and a potentially valuable molecular marker for human cancer. PMID:23028699

  2. Association of a Human FABP1 Gene Promoter Region Polymorphism with Altered Serum Triglyceride Levels.

    PubMed

    Peng, Xian-E; Wu, Yun-Li; Zhu, Yi-Bing; Huang, Rong-Dong; Lu, Qing-Qing; Lin, Xu

    2015-01-01

    Liver fatty acid-binding protein (L-FABP), also known as fatty acid-binding protein 1 (FABP1), is a key regulator of hepatic lipid metabolism. Elevated FABP1 levels are associated with an increased risk of cardiovascular disease (CVD) and metabolic syndromes. In this study, we examine the association of FABP1 gene promoter variants with serum FABP1 and lipid levels in a Chinese population. Four promoter single-nucleotide polymorphisms (SNPs) of FABP1 gene were genotyped in a cross-sectional survey of healthy volunteers (n = 1,182) from Fuzhou city of China. Results showed that only the rs2919872 G>A variant was significantly associated with serum TG concentration(P = 0.032).Compared with the rs2919872 G allele, rs2919872 A allele contributed significantly to reduced serum TG concentration, and this allele dramatically decreased the FABP1 promoter activity(P < 0.05). The rs2919872 A allele carriers had considerably lower serum FABP1 levels than G allele carriers (P < 0.01). In the multivariable linear regression analysis, the rs2919872 A allele was negatively associated with serum FABP1 levels (β = -0.320, P = 0.003), while serum TG levels were positively associated with serum FABP1 levels (β = 0.487, P = 0.014). Our data suggest that compared with the rs2919872 G allele, the rs2919872 A allele reduces the transcriptional activity of FABP1 promoter, and thereby may link FABP1 gene variation to TG level in humans.

  3. A petal-specific InMYB1 promoter from Japanese morning glory: a useful tool for molecular breeding of floricultural crops.

    PubMed

    Azuma, Mirai; Morimoto, Reina; Hirose, Mana; Morita, Yasumasa; Hoshino, Atsushi; Iida, Shigeru; Oshima, Yoshimi; Mitsuda, Nobutaka; Ohme-Takagi, Masaru; Shiratake, Katsuhiro

    2016-01-01

    Production of novel transgenic floricultural crops with altered petal properties requires transgenes that confer a useful trait and petal-specific promoters. Several promoters have been shown to control transgenes in petals. However, all suffer from inherent drawbacks such as low petal specificity and restricted activity during the flowering stage. In addition, the promoters were not examined for their ability to confer petal-specific expression in a wide range of plant species. Here, we report the promoter of InMYB1 from Japanese morning glory as a novel petal-specific promoter for molecular breeding of floricultural crops. First, we produced stable InMYB1_1kb::GUS transgenic Arabidopsis and Eustoma plants and characterized spatial and temporal expression patterns under the control of the InMYB1 promoter by histochemical β-glucuronidase (GUS) staining. GUS staining patterns were observed only in petals. This result showed that the InMYB1 promoter functions as a petal-specific promoter. Second, we transiently introduced the InMYB1_1 kb::GUS construct into Eustoma, chrysanthemum, carnation, Japanese gentian, stock, rose, dendrobium and lily petals by particle bombardment. GUS staining spots were observed in Eustoma, chrysanthemum, carnation, Japanese gentian and stock. These results showed that the InMYB1 promoter functions in most dicots. Third, to show the InMYB1 promoter utility in molecular breeding, a MIXTA-like gene function was suppressed or enhanced under the control of InMYB1 promoter in Arabidopsis. The transgenic plant showed a conspicuous morphological change only in the form of wrinkled petals. Based on these results, the InMYB1 promoter can be used as a petal-specific promoter in molecular breeding of floricultural crops. © 2015 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

  4. Abluminal Stimulation of Sphingosine 1-Phosphate Receptors 1 and 3 Promotes and Stabilizes Endothelial Sprout Formation

    PubMed Central

    Lenz, Steven M.; Awojoodu, Anthony O.

    2015-01-01

    Local delivery of lipid mediators has become a promising new approach for therapeutic angiogenesis and regenerative medicine. In this study, we investigated how gradient stimulation (either abluminal/distal or luminal/proximal) of engineered microvessels with sphingosine 1-phosphate (S1P) receptor-subtype-targeted molecules affects endothelial sprout growth using a microfluidic device. Our studies show that distal stimulation of microvessels with FTY720, an S1P1/3 selective agonist, promotes both arterial and venular sprout growth, whereas proximal stimulation does not. Using novel pharmacological antagonists of S1P receptor subtypes, we further show that S1P3 functionality is necessary for VEGF-induced sprouting, and confirmed these findings ex vivo using a murine aortic ring assay from S1P3-deficient mice. S1P3 agonist stimulation enhanced vascular stability in both cell types via upregulation of the interendothelial junction protein VE-cadherin. Lastly, S1P3 activation under flow promoted endothelial sprouting and branching while decreasing migratory cell fate in the microfluidic device. We used an in vivo murine dorsal skinfold window chamber model to confirm S1P3's role in neovascular branching. Together, these data suggest that a distal transendothelial gradient of S1P1/3-targeted drugs is an effective technique for both enhancing and stabilizing capillary morphogenesis in angiogenic applications. PMID:25315888

  5. Ginsenoside Rb1 promotes browning through regulation of PPARγ in 3T3-L1 adipocytes.

    PubMed

    Mu, Qianqian; Fang, Xin; Li, Xiaoke; Zhao, Dandan; Mo, Fangfang; Jiang, Guangjian; Yu, Na; Zhang, Yi; Guo, Yubo; Fu, Min; Liu, Jun-Li; Zhang, Dongwei; Gao, Sihua

    2015-10-23

    Browning of white adipocyte tissue (WAT) has received considerable attention due to its potential implication in preventing obesity and related comorbidities. Ginsenoside Rb1 is reported to improve glycolipid metabolism and reduce body weight in obese animals. However whether the body reducing effect mediates by browning effect remains unclear. For this purpose, 3T3-L1 adipocytes were used to study the effect of ginsenoside Rb1 on browning adipocytes specific genes and oxygen consumptions. The results demonstrate that 10 μM of ginsenoside Rb1 increases basal glucose uptake and promoted browning evidenced by significant increases in mRNA expressions of UCP-1, PGC-1α and PRDM16 in 3T3-L1 mature adipocytes. Further, ginsenoside Rb1 also increases PPARγ activity. And the browning effect is abrogated by GW9692, a PPARγ antagonist. In addition, ginsenoside Rb1 increases basal respiration rate, ATP production and uncoupling capacity in 3T3-L1 adipocytes. Those effects are also blunted by GW9692. The results suggest that ginsenoside Rb1 promote browning of 3T3-L1 adipocytes through induction of PPARγ. Our finding offer a new source to discover browning agonists and also useful to understand and extend the applications of ginseng and its constituents. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Identification and characterization of an alternative promoter of the human PGC-1{alpha} gene

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yoshioka, Toyo; Inagaki, Kenjiro; Noguchi, Tetsuya, E-mail: noguchi@med.kobe-u.ac.jp

    2009-04-17

    The transcriptional regulator peroxisome proliferator-activated receptor-{gamma} coactivator-1{alpha} (PGC-1{alpha}) controls mitochondrial biogenesis and energy homeostasis. Although physical exercise induces PGC-1{alpha} expression in muscle, the underlying mechanism of this effect has remained incompletely understood. We recently identified a novel muscle-enriched isoform of PGC-1{alpha} transcript (designated PGC-1{alpha}-b) that is derived from a previously unidentified first exon. We have now cloned and characterized the human PGC-1{alpha}-b promoter. The muscle-specific transcription factors MyoD and MRF4 transactivated this promoter through interaction with a proximal E-box motif. Furthermore, either forced expression of Ca{sup 2+}- and calmodulin-dependent protein kinase IV (CaMKIV), calcineurin A, or the p38 mitogen-activated proteinmore » kinase (p38 MAPK) kinase MKK6 or the intracellular accumulation of cAMP activated the PGC-1{alpha}-b promoter in cultured myoblasts through recruitment of cAMP response element (CRE)-binding protein (CREB) to a putative CRE located downstream of the E-box. Our results thus reveal a potential molecular basis for isoform-specific regulation of PGC-1{alpha} expression in contracting muscle.« less

  7. PPARγ and NF-κB regulate the gene promoter activity of their shared repressor, TNIP1

    PubMed Central

    Gurevich, Igor; Zhang, Carmen; Encarnacao, Priscilla C.; Struzynski, Charles P.; Livings, Sarah E.; Aneskievich, Brian J.

    2011-01-01

    Human TNFAIP3 interacting protein 1 (TNIP1) has diverse functions including support of HIV replication through its interaction with viral Nef and matrix proteins, reduction of TNFα-induced signaling through its interaction with NF-κB pathway proteins, and corepression of agonist-bound retinoic acid receptors and peroxisome proliferator-activated receptors (PPAR). The wide tissue distribution of TNIP1 provides the opportunity to influence numerous cellular responses in these roles and defining control of TNIP1 expression would be central to improved understanding of its impact on cell function. We cloned 6kb of the human TNIP1 promoter and performed predictive and functional analyses to identify regulatory elements. The promoter region proximal to the transcription start site is GC-rich without a recognizable TATA box. In contrast to this proximal ~500bp region, 6kb of the promoter increased reporter construct constitutive activity over five-fold. Throughout the 6kb length, in silico analysis identified several potential binding sites for both constitutive and inducible transcription factors; among the latter were candidate NF-κB binding sequences and peroxisome proliferator response elements (PPREs). We tested NF-κB and PPAR regulation of the endogenous TNIP1 gene and cloned promoter by expression studies, electrophoretic mobility shift assays, and chromatin immunoprecipitations. We validated NF-κB sites in the TNIP1 promoter proximal and distal regions as well as one PPRE in the distal region. The ultimate control of the TNIP1 promoter is likely to be a combination of constitutive transcription factors and those subject to activation such as NF-κB and PPAR. PMID:22001530

  8. TET1 promotes cisplatin-resistance via demethylating the vimentin promoter in ovarian cancer.

    PubMed

    Han, Xi; Zhou, Yuanyuan; You, Yuanyi; Lu, Jiaojiao; Wang, Lijie; Hou, Huilian; Li, Jing; Chen, Wei; Zhao, Le; Li, Xu

    2017-04-01

    The development of chemo-resistance impairs the outcome of the first line platinum-based chemotherapies for ovarian cancer. Deregulation of DNA methylation/demethylation provides a critical mechanism for the occurrence of chemo-resistance. The ten-eleven translocation (TET) family of dioxygenases including TET1/2/3 plays an important part in DNA demethylation, but their roles in cisplatin resistance have not been elucidated. Using cisplatin-sensitive and cisplatin-resistant ovarian cancer cell models, we found that TET1 was significantly upregulated in cisplatin-resistant CP70 cells compared with that in cisplatin-sensitive A2780 cells. Ectopic expression of TET1 in A2780 cells promoted cisplatin resistance and decreased cytotoxicity induced by cisplatin, while inhibition of TET1 by siRNA transfection in CP70 cells attenuated cisplatin resistance and enhanced cytotoxicity of cisplatin. Increased TET1 induced re-expression of vimentin through active DNA demethylation, and cause partial epithelial-to-mesenchymal (EMT) in A2780 cells. Contrarily, knocking down of TET1 in CP70 cells reduced vimentin expression and reversed EMT process. Immunohistochemical analysis of TET1 in human ovarian cancer tissues revealed that TET1 existed in nucleus and cytoplasm in ovarian cancer tissues. And the expression of nuclear TET1 was positively correlated with residual tumor and chemotherapeutic response. Thus, TET1 expression causes resistance to cisplatin and one of the targets of TET1 action is vimentin in ovarian cancer. © 2017 International Federation for Cell Biology.

  9. Growth-promoting Sphingomonas paucimobilis ZJSH1 associated with Dendrobium officinale through phytohormone production and nitrogen fixation

    PubMed Central

    Yang, Suijuan; Zhang, Xinghai; Cao, Zhaoyun; Zhao, Kaipeng; Wang, Sai; Chen, Mingxue; Hu, Xiufang

    2014-01-01

    Growth-promoting Sphingomonas paucimobilis ZJSH1, associated with Dendrobium officinale, a traditional Chinese medicinal plant, was characterized. At 90 days post-inoculation, strain ZJSH1 significantly promoted the growth of D. officinale seedlings, with increases of stems by 8.6% and fresh weight by 7.5%. Interestingly, the polysaccharide content extracted from the inoculated seedlings was 0.6% higher than that of the control. Similar growth promotion was observed with the transplants inoculated with strain ZJSH1. The mechanism of growth promotion was attributed to a combination of phytohormones and nitrogen fixation. Strain ZJSH1 was found using the Kjeldahl method to have a nitrogen fixation activity of 1.15 mg l−1, which was confirmed by sequencing of the nifH gene. Using high-performance liquid chromatography-mass spectrometry, strain ZJSH1 was found to produce various phytohormones, including salicylic acid (SA), indole-3-acetic acid (IAA), Zeatin and abscisic acid (ABA). The growth curve showed that strain ZJSH1 grew well in the seedlings, especially in the roots. Accordingly, much higher contents of SA, ABA, IAA and c-ZR were detected in the inoculated seedlings, which may play roles as both phytohormones and ‘Systemic Acquired Resistance’ drivers. Nitrogen fixation and secretion of plant growth regulators (SA, IAA, Zeatin and ABA) endow S. paucimobilis ZJSH1 with growth-promoting properties, which provides a potential for application in the commercial growth of D. officinale. PMID:25142808

  10. PLK1 (polo like kinase 1) inhibits MTOR complex 1 and promotes autophagy.

    PubMed

    Ruf, Stefanie; Heberle, Alexander Martin; Langelaar-Makkinje, Miriam; Gelino, Sara; Wilkinson, Deepti; Gerbeth, Carolin; Schwarz, Jennifer Jasmin; Holzwarth, Birgit; Warscheid, Bettina; Meisinger, Chris; van Vugt, Marcel A T M; Baumeister, Ralf; Hansen, Malene; Thedieck, Kathrin

    2017-03-04

    Mechanistic target of rapamycin complex 1 (MTORC1) and polo like kinase 1 (PLK1) are major drivers of cancer cell growth and proliferation, and inhibitors of both protein kinases are currently being investigated in clinical studies. To date, MTORC1's and PLK1's functions are mostly studied separately, and reports on their mutual crosstalk are scarce. Here, we identify PLK1 as a physical MTORC1 interactor in human cancer cells. PLK1 inhibition enhances MTORC1 activity under nutrient sufficiency and in starved cells, and PLK1 directly phosphorylates the MTORC1 component RPTOR/RAPTOR in vitro. PLK1 and MTORC1 reside together at lysosomes, the subcellular site where MTORC1 is active. Consistent with an inhibitory role of PLK1 toward MTORC1, PLK1 overexpression inhibits lysosomal association of the PLK1-MTORC1 complex, whereas PLK1 inhibition promotes lysosomal localization of MTOR. PLK1-MTORC1 binding is enhanced by amino acid starvation, a condition known to increase autophagy. MTORC1 inhibition is an important step in autophagy activation. Consistently, PLK1 inhibition mitigates autophagy in cancer cells both under nutrient starvation and sufficiency, and a role of PLK1 in autophagy is also observed in the invertebrate model organism Caenorhabditis elegans. In summary, PLK1 inhibits MTORC1 and thereby positively contributes to autophagy. Since autophagy is increasingly recognized to contribute to tumor cell survival and growth, we propose that cautious monitoring of MTORC1 and autophagy readouts in clinical trials with PLK1 inhibitors is needed to develop strategies for optimized (combinatorial) cancer therapies targeting MTORC1, PLK1, and autophagy.

  11. Mps1 promotes rapid centromere accumulation of Aurora B.

    PubMed

    van der Waal, Maike S; Saurin, Adrian T; Vromans, Martijn J M; Vleugel, Mathijs; Wurzenberger, Claudia; Gerlich, Daniel W; Medema, René H; Kops, Geert J P L; Lens, Susanne M A

    2012-09-01

    Aurora B localization to mitotic centromeres, which is required for proper chromosome alignment during mitosis, relies on Haspin-dependent histone H3 phosphorylation and on Bub1-dependent histone H2A phosphorylation--which interacts with Borealin through a Shugoshin (Sgo) intermediate. We demonstrate that Mps1 stimulates the latter recruitment axis. Mps1 activity enhances H2A-T120ph and is critical for Sgo1 recruitment to centromeres, thereby promoting Aurora B centromere recruitment in early mitosis. Importantly, chromosome biorientation defects caused by Mps1 inhibition are improved by restoring Aurora B centromere recruitment. As Mps1 kinetochore localization reciprocally depends on Aurora B, we propose that this Aurora B-Mps1 recruitment circuitry cooperates with the Aurora B-Haspin feedback loop to ensure rapid centromere accumulation of Aurora B at the onset of mitosis.

  12. Allelic combinations of promoter and exon 2 in DQB1 in dogs and wolves.

    PubMed

    Berggren, Karin T; Seddon, Jennifer M

    2008-07-01

    Polymorphism of PBRs of the major histocompatibility complex (MHC) genes is well recognized, but the polymorphism also extends to proximal promoter regions. Examining DQB1 variability in dogs and wolves, we identified 7 promoter variants and 13 exon 2 alleles among 89 dogs, including a previously unknown DQB1 exon 2 allele, and 8 promoter variants and 9 exon 2 alleles among 85 wolves. As expected from previous studies and from a close chromosomal location, strong linkage disequilibrium was demonstrated in both wolves and dogs by having significantly fewer promoter/exon 2 combinations than expected from simulations of randomized data sets. Interestingly, we noticed weaker haplotypic associations in dogs than in wolves. Dogs had twice as many promoter/exon 2 combinations as wolves and an almost 2-fold difference in the number of exon 2 alleles per promoter variant. This difference was not caused by an admixture of breeds in our group of dogs because the high ratio of observed to expected number of haplotypes persisted within a single dog breed, the German Shepherd. Ewens-Watterson tests indicated that both the promoter and exon 2 are under the balancing selection, and both regions appear to be more recently derived in the dog than in the wolf. Hence, although reasons for the differences are unknown, they may relate to altered selection pressure on patterns of expression. Deviations from normal MHC expression patterns have been associated with autoimmune diseases, which occur frequently in several dog breeds. Further knowledge about these deviations may help us understand the source of such diseases.

  13. NFATc1 regulation of the human β3 integrin promoter in osteoclast differentiation

    PubMed Central

    Crotti, Tania N.; Flannery, Merrilee; Walsh, Nicole C.; Fleming, Joseph D.; Goldring, Steven R.; McHugh, Kevin P.

    2006-01-01

    The transcription factor NFATc1 plays an essential role in transducing signals from RANKL in osteoclast differentiation. To date, however, the specific transcriptional targets of NFATc1 are unknown. Expression of the β3 integrin is required for normal osteoclast function. We therefore examined the role of NFATc1 in human β3 integrin expression in osteoclast differentiation. Analysis of the mouse and human β3 gene promoters revealed considerable sequence homology across a 1.3 kb region upstream of the transcription start site (TSS), with conserved NFAT binding elements present. The region −1242 to +29 (relative to the TSS) was cloned as a luciferase reporter construct (pB3-1.3) and a deletion construct removing to −997 (pB3-1) made. The deletion of 245 bp 5′ removed three conserved NFAT sites including a consensus NFAT:AP-1 site. The pB3-1.3 reporter construct was induced by treatment with RANKL in the range 2.5–40 ng/ml and dose-dependently induced by co-transfection with human NFATc1 in RAW264.7 cells. The pB3-1 deletion construct was minimally induced with RANKL treatment and unresponsive to co-transfected NFATc1. Direct NFAT binding to two of the consensus NFAT sites within this 245 bp 5′ region was demonstrated by EMSA and supershift with anti-NFAT antibodies. Mutation of two of the conserved NFAT sites in the −1242 to −997 fragment was required to prevent binding. The double NFAT mutant, in the context of the full-length promoter was unresponsive to RANKL treatment or co-transfected NFATc1. We generated cell-permeable TAT-dominant-negative (dn)NFATc1 fusion proteins to assess the effect of blockade of NFAT signaling. Transduction with dnNFAT inhibited RANKL induction of the human β3 integrin promoter. Involvement of the NFATc1-calcineurin pathway in regulating the human β3 integrin promoter was further confirmed using the calcineurin pathway inhibitory peptide 11R-VIVIT. Together these results establish the β3 gene as a direct target of

  14. Bilirubin UDP-Glucuronosyltransferase 1A1 (UGT1A1) Gene Promoter Polymorphisms and HPRT, Glycophorin A, and Micronuclei Mutant Frequencies in Human Blood

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Grant, D; Hall, I J; Eastmond, D

    2004-10-06

    A dinucleotide repeat polymorphism (5-, 6-, 7-, or 8-TA units) has been identified within the promoter region of UDP-glucuronosyltransferase 1A1 gene (UGT1A1). The 7-TA repeat allele has been associated with elevated serum bilirubin levels that cause a mild hyperbilirubinemia (Gilbert's syndrome). Studies suggest that promoter transcriptional activity of UGT1A1 is inversely related to the number of TA repeats and that unconjugated bilirubin concentration increases directly with the number of TA repeat elements. Because bilirubin is a known antioxidant, we hypothesized that UGT1A1 repeats associated with higher bilirubin may be protective against oxidative damage. We examined the effect of UGT1A1 genotypemore » on somatic mutant frequency in the hypoxanthine-guanine phosphoribosyl-transferase (HPRT) gene in human lymphocytes and the glycophorin A (GPA) gene of red blood cells (both N0, NN mutants), and the frequency of lymphocyte micronuclei (both kinetochore (K) positive or micronuclei K negative) in 101 healthy smoking and nonsmoking individuals. As hypothesized, genotypes containing 7-TA and 8-TA displayed marginally lower GPA{_}NN mutant frequency relative to 5/5, 5/6, 6/6 genotypes (p<0.05). In contrast, our analysis showed that lower expressing UGT1A1 alleles (7-TA and 8-TA) were associated with modestly increased HPRT mutation frequency (p<0.05) while the same low expression genotypes were not significantly associated with micronuclei frequencies (K-positive or K-negative) when compared to high expression genotypes (5-TA and 6-TA). We found weak evidence that UGT1A1 genotypes containing 7-TA and 8-TA were associated with increased GPA{_}N0 mutant frequency relative to 5/5, 5/6, 6/6 genotypes (p<0.05). These data suggest that UGT1A1 genotype may modulate somatic mutation of some types, in some cell lineages, by a mechanism not involving bilirubin antioxidant activity. More detailed studies examining UGT1A1 promoter variation, oxidant/antioxidant balance and

  15. A functional SNP in the promoter region of TCOF1 is associated with reduced gene expression and YY1 DNA-protein interaction.

    PubMed

    Masotti, Cibele; Armelin-Correa, Lucia M; Splendore, Alessandra; Lin, Chin J; Barbosa, Angela; Sogayar, Mari C; Passos-Bueno, Maria Rita

    2005-10-10

    Treacher Collins syndrome (TCS) is an autosomal dominant craniofacial malformation caused by null mutations in the TCOF1 gene. High inter and intra familial clinical variability, ranging from mild malar hypoplasia to perinatal death due to airway collapse is observed, but, to date, no genotype-phenotype correlation has been reported. Considering haploinsufficiency as the molecular mechanism underlying the disease, we have hypothesized that mutations in the promoter region of the gene, which has never been previously characterized, in trans with a pathogenic mutation, could modulate the phenotype. Therefore, the aims of the present study were to determine the TCOF1 gene's core promoter and to identify mutations in this region that could contribute to the phenotypic variation observed in this syndrome. We have delimitated the minimal promoter to a region of less than 150 bp, with 63% of identity among 5 different species. We screened 1.2 kbp of the TCOF1 5' flanking sequence in the DNA obtained from 21 patients and 51 controls and identified four new single nucleotide polymorphisms (SNPs), one of which (-346C>T), was proved to be functional, as it decreased the promoter activity by 38%. Electrophoretic mobility shift assay (EMSA) analysis demonstrated that the -346T allele impairs DNA-binding to the YY1 transcription factor. This promoter variant represents a candidate allele to explain the clinical variability in patients bearing TCS.

  16. Sumoylation of Rap1 mediates the recruitment of TFIID to promote transcription of ribosomal protein genes

    PubMed Central

    Chymkowitch, Pierre; Nguéa P, Aurélie; Aanes, Håvard; Koehler, Christian J.; Thiede, Bernd; Lorenz, Susanne; Meza-Zepeda, Leonardo A.; Klungland, Arne; Enserink, Jorrit M.

    2015-01-01

    Transcription factors are abundant Sumo targets, yet the global distribution of Sumo along the chromatin and its physiological relevance in transcription are poorly understood. Using Saccharomyces cerevisiae, we determined the genome-wide localization of Sumo along the chromatin. We discovered that Sumo-enriched genes are almost exclusively involved in translation, such as tRNA genes and ribosomal protein genes (RPGs). Genome-wide expression analysis showed that Sumo positively regulates their transcription. We also discovered that the Sumo consensus motif at RPG promoters is identical to the DNA binding motif of the transcription factor Rap1. We demonstrate that Rap1 is a molecular target of Sumo and that sumoylation of Rap1 is important for cell viability. Furthermore, Rap1 sumoylation promotes recruitment of the basal transcription machinery, and sumoylation of Rap1 cooperates with the target of rapamycin kinase complex 1 (TORC1) pathway to promote RPG transcription. Strikingly, our data reveal that sumoylation of Rap1 functions in a homeostatic feedback loop that sustains RPG transcription during translational stress. Taken together, Sumo regulates the cellular translational capacity by promoting transcription of tRNA genes and RPGs. PMID:25800674

  17. Proteomic identification of an embryo-specific 1Cys-Prx promoter and analysis of its activity in transgenic rice.

    PubMed

    Kim, Je Hein; Jung, In Jung; Kim, Dool Yi; Fanata, Wahyu Indra; Son, Bo Hwa; Yoo, Jae Yong; Harmoko, Rikno; Ko, Ki Seong; Moon, Jeong Chan; Jang, Ho Hee; Kim, Woe Yeon; Kim, Jae-Yean; Lim, Chae Oh; Lee, Sang Yeol; Lee, Kyun Oh

    2011-04-29

    Proteomic analysis of a rice callus led to the identification of 10 abscisic acid (ABA)-induced proteins as putative products of the embryo-specific promoter candidates. 5'-flanking sequence of 1 Cys-Prx, a highly-induced protein gene, was cloned and analyzed. The transcription initiation site of 1 Cys-Prx maps 96 nucleotides upstream of the translation initiation codon and a TATA-box and putative seed-specific cis-acting elements, RYE and ABRE, are located 26, 115 and 124 bp upstream of the transcription site, respectively. β-glucuronidase (GUS) expression driven by the 1 Cys-Prx promoters was strong in the embryo and aleurone layer and the activity reached up to 24.9 ± 3.3 and 40.5 ± 2.1 pmol (4 MU/min/μg protein) in transgenic rice seeds and calluses, respectively. The activity of the 1 Cys-Prx promoters is much higher than that of the previously-identified embryo-specific promoters, and comparable to that of strong endosperm-specific promoters in rice. GUS expression driven by the 1 Cys-Prx promoters has been increased by ABA treatment and rapidly induced by wounding in callus and at the leaf of the transgenic plants, respectively. Furthermore, ectopic expression of the GUS construct in Arabidopsis suggested that the 1 Cys-Prx promoter also has strong activity in seeds of dicot plants. Copyright © 2011 Elsevier Inc. All rights reserved.

  18. Insulin/IGF-1 signaling mutants reprogram ER stress response regulators to promote longevity.

    PubMed

    Henis-Korenblit, Sivan; Zhang, Peichuan; Hansen, Malene; McCormick, Mark; Lee, Seung-Jae; Cary, Michael; Kenyon, Cynthia

    2010-05-25

    When unfolded proteins accumulate in the endoplasmic reticulum (ER), the unfolded protein response is activated. This ER stress response restores ER homeostasis by coordinating processes that decrease translation, degrade misfolded proteins, and increase the levels of ER-resident chaperones. Ribonuclease inositol-requiring protein-1 (IRE-1), an endoribonuclease that mediates unconventional splicing, and its target, the XBP-1 transcription factor, are key mediators of the unfolded protein response. In this study, we show that in Caenorhabditis elegans insulin/IGF-1 pathway mutants, IRE-1 and XBP-1 promote lifespan extension and enhance resistance to ER stress. We show that these effects are not achieved simply by increasing the level of spliced xbp-1 mRNA and expression of XBP-1's normal target genes. Instead, in insulin/IGF-1 pathway mutants, XBP-1 collaborates with DAF-16, a FOXO-transcription factor that is activated in these mutants, to enhance ER stress resistance and to activate new genes that promote longevity.

  19. Hypermethylation of the TSLC1 Gene Promoter in Primary Gastric Cancers and Gastric Cancer Cell Lines

    PubMed Central

    Honda, Teiichiro; Waki, Takayoshi; Jin, Zhe; Sato, Kiyoshi; Motoyama, Teiichi; Kawata, Sumio; Kimura, Wataru; Nishizuka, Satoshi; Murakami, Yoshinori

    2002-01-01

    The TSLC1 (tumor suppressor in lung cancer–1) gene is a novel tumor suppressor gene on chromosomal region 11q23.2, and is frequently inactivated by concordant promoter hypermethylation and loss of heterozygosity (LOH) in non‐small cell lung cancer (NSCLC). Because LOH on 11q has also been observed frequently in other human neoplasms including gastric cancer, we investigated the promoter methylation status of TSLC1 in 10 gastric cancer cell lines and 97 primary gastric cancers, as well as the corresponding non‐cancerous gastric tissues, by bisulfite‐SSCP analysis followed by direct sequencing. Allelic status of the TSLC1 gene was also investigated in these cell lines and primary gastric cancers. The TSLC1 promoter was methylated in two gastric cancer cell lines, KATO‐III and ECC10, and in 15 out of 97 (16%) primary gastric cancers. It was not methylated in non‐cancerous gastric tissues, suggesting that this hypermethylation is a cancer‐specific alteration. KATO‐III and ECC10 cells retained two alleles of TSLC1, both of which showed hypermethylation, associated with complete loss of gene expression. Most of the primary gastric cancers with promoter methylation also retained heterozygosity at the TSLC1 locus on 11q23.2. These data indicate that bi‐allelic hypermethylation of the TSLC1 promoter and resulting gene silencing occur in a subset of primary gastric cancers. PMID:12716461

  20. Regulation of the tumor marker Fascin by the viral oncoprotein Tax of human T-cell leukemia virus type 1 (HTLV-1) depends on promoter activation and on a promoter-independent mechanism.

    PubMed

    Mohr, Caroline F; Gross, Christine; Bros, Matthias; Reske-Kunz, Angelika B; Biesinger, Brigitte; Thoma-Kress, Andrea K

    2015-11-01

    Adult T-cell leukemia/lymphoma is a highly infiltrative neoplasia of CD4(+) T-lymphocytes that occurs in about 5% of carriers infected with the deltaretrovirus human T-cell leukemia virus type 1 (HTLV-1). The viral oncoprotein Tax perturbs cellular signaling pathways leading to upregulation of host cell factors, amongst them the actin-bundling protein Fascin, an invasion marker of several types of cancer. However, transcriptional regulation of Fascin by Tax is poorly understood. In this study, we identified a triple mode of transcriptional induction of Fascin by Tax, which requires (1) NF-κB-dependent promoter activation, (2) a Tax-responsive region in the Fascin promoter, and (3) a promoter-independent mechanism sensitive to the Src family kinase inhibitor PP2. Thus, Tax regulates Fascin by a multitude of signals. Beyond, using Tax-expressing and virus-transformed lymphocytes as a model system, our study is the first to identify the invasion marker Fascin as a novel target of PP2, an inhibitor of metastasis. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Puerarin promotes ABCA1-mediated cholesterol efflux and decreases cellular lipid accumulation in THP-1 macrophages.

    PubMed

    Li, Cong-Hui; Gong, Duo; Chen, Ling-Yan; Zhang, Min; Xia, Xiao-Dan; Cheng, Hai-Peng; Huang, Chong; Zhao, Zhen-Wang; Zheng, Xi-Long; Tang, Xiao-Er; Tang, Chao-Ke

    2017-09-15

    It was reported that puerarin decreases the total cholesterol, low-density lipoprotein cholesterol (LDL-C), triglyceride (TG) and increases high-density lipoprotein cholesterol (HDL-C) level, but the underlying mechanism is unclear. This study was designed to determine whether puerarin decreased lipid accumulation via up-regulation of ABCA1-mediated cholesterol efflux in THP-1 macrophage-derived foam cells. Our results showed that puerarin significantly promoted the expression of ATP-binding cassette transporter A1 (ABCA1) mRNA and protein via the AMP-activated protein kinase (AMPK)-peroxisome proliferator-activated receptor gamma (PPARγ)-liver X receptor-alpha (LXR-α) pathway and decreased cellular lipid accumulation in human THP-1 macrophage-derived foam cells. The miR-7 directly targeted 3' untranslated region of STK11 (Serine/Threonine Kinase 11), which activated the AMPK pathway. Transfection with miR-7 mimic significantly reduced STK11 expression in puerarin-treated macrophages, decreased the phosphorylation of AMPK, down-regulated the expression of the PPARγ-LXR-α-ABCA1 expression. Additionally, treatment with miR-7 decreased cholesterol efflux and increased cholesterol levels in THP-1 macrophage-derived foam cells. Our study demonstrates that puerarin promotes ABCA1-mediated cholesterol efflux and decreases intracellular cholesterol levels through the pathway involving miR-7, STK11, and the AMPK-PPARγ-LXR-α-ABCA1 cascade. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Negative modulation of the chicken infectious anemia virus promoter by COUP-TF1 and an E box-like element at the transcription start site binding deltaEF1.

    PubMed

    Miller, Myrna M; Jarosinski, Keith W; Schat, Karel A

    2008-12-01

    Expression of enhanced green fluorescent protein (EGFP) under control of the promoter-enhancer of chicken infectious anemia virus (CAV) is increased in an oestrogen receptor-enhanced cell line when treated with oestrogen and the promoter-enhancer binds unidentified proteins that recognize a consensus oestrogen response element (ERE). Co-transfection assays with the CAV promoter and the nuclear receptor chicken ovalbumin upstream promoter transcription factor 1 (COUP-TF1) showed that expression of EGFP was decreased by 50 to 60 % in DF-1 and LMH cells. The CAV promoter that included sequences at and downstream of the transcription start point had less expression than a short promoter construct. Mutation of a putative E box at this site restored expression levels. Electromobility shift assays showed that the transcription regulator delta-EF1 (deltaEF1) binds to this E box region. These findings indicate that the CAV promoter activity can be affected directly or indirectly by COUP-TF1 and deltaEF1.

  3. Association of a Human FABP1 Gene Promoter Region Polymorphism with Altered Serum Triglyceride Levels

    PubMed Central

    Zhu, Yi-bing; Huang, Rong-dong; Lu, Qing-Qing; Lin, Xu

    2015-01-01

    Liver fatty acid-binding protein (L-FABP), also known as fatty acid-binding protein 1 (FABP1), is a key regulator of hepatic lipid metabolism. Elevated FABP1 levels are associated with an increased risk of cardiovascular disease (CVD) and metabolic syndromes. In this study, we examine the association of FABP1 gene promoter variants with serum FABP1 and lipid levels in a Chinese population. Four promoter single-nucleotide polymorphisms (SNPs) of FABP1 gene were genotyped in a cross-sectional survey of healthy volunteers (n = 1,182) from Fuzhou city of China. Results showed that only the rs2919872 G>A variant was significantly associated with serum TG concentration(P = 0.032).Compared with the rs2919872 G allele, rs2919872 A allele contributed significantly to reduced serum TG concentration, and this allele dramatically decreased the FABP1 promoter activity(P < 0.05). The rs2919872 A allele carriers had considerably lower serum FABP1 levels than G allele carriers (P < 0.01). In the multivariable linear regression analysis, the rs2919872 A allele was negatively associated with serum FABP1 levels (β = —0.320, P = 0.003), while serum TG levels were positively associated with serum FABP1 levels (β = 0.487, P = 0.014). Our data suggest that compared with the rs2919872 G allele, the rs2919872 A allele reduces the transcriptional activity of FABP1 promoter, and thereby may link FABP1 gene variation to TG level in humans. PMID:26439934

  4. Set1/COMPASS and Mediator are repurposed to promote epigenetic transcriptional memory.

    PubMed

    D'Urso, Agustina; Takahashi, Yoh-Hei; Xiong, Bin; Marone, Jessica; Coukos, Robert; Randise-Hinchliff, Carlo; Wang, Ji-Ping; Shilatifard, Ali; Brickner, Jason H

    2016-06-23

    In yeast and humans, previous experiences can lead to epigenetic transcriptional memory: repressed genes that exhibit mitotically heritable changes in chromatin structure and promoter recruitment of poised RNA polymerase II preinitiation complex (RNAPII PIC), which enhances future reactivation. Here, we show that INO1 memory in yeast is initiated by binding of the Sfl1 transcription factor to the cis-acting Memory Recruitment Sequence, targeting INO1 to the nuclear periphery. Memory requires a remodeled form of the Set1/COMPASS methyltransferase lacking Spp1, which dimethylates histone H3 lysine 4 (H3K4me2). H3K4me2 recruits the SET3C complex, which plays an essential role in maintaining this mark. Finally, while active INO1 is associated with Cdk8(-) Mediator, during memory, Cdk8(+) Mediator recruits poised RNAPII PIC lacking the Kin28 CTD kinase. Aspects of this mechanism are generalizable to yeast and conserved in human cells. Thus, COMPASS and Mediator are repurposed to promote epigenetic transcriptional poising by a highly conserved mechanism.

  5. MicroRNA-194 promotes osteoblast differentiation via downregulating STAT1

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, Jun; He, Xijing; Wei, Wenzhi

    Osteoblast differentiation is a vital process in maintaining bone homeostasis in which various transcriptional factors, signaling molecules, and microRNAs (miRNAs) are involved. Recently, signal transducer and activator of transcription 1 (STAT1) has been found to play an important role in regulating osteoblast differentiation. Here, we identified that STAT1 expression was regulated by miR-194. Using mouse bone mesenchymal stem cells (BMSCs), we found that miR-194 expression was significantly increased following osteoblast differentiation induction. Overexpression of miR-194 by lentivirus-mediated gene transfer markedly increased osteoblast differentiation, whereas inhibition of miR-194 significantly suppressed osteoblast differentiation of BMSCs. Using a dual-luciferase reporter assay, a directmore » interaction between miR-194 and the 3′-untranslated region (UTR) of STAT1 was confirmed. Additionally, miR-194 regulated mRNA and protein expression of STAT1 in BMSCs. Further analysis showed that miR-194 overexpression promoted the nuclear translocation of runt-related transcription factor 2 (Runx2), which is critical for osteoblast differentiation. In contrast, inhibition of miR-194 blocked the nuclear translocation of Runx2. Moreover, overexpression of STAT1 significantly blocked Runx2 nuclear translocation and osteoblast differentiation mediated by miR-194 overexpression. Taken together, our data suggest that miR-194 regulates osteoblast differentiation through modulating STAT1-mediated Runx2 nuclear translocation. - Highlights: • Overexpression of miR-194 significantly increased osteoblast differentiation. • miR-194 directly targeted the 3′- UTR of STAT1. • miR-194 regulated the expression of STAT1. • Overexpression of miR-194 promoted the nuclear translocation of Runx2.« less

  6. Tumour MLH1 promoter region methylation testing is an effective prescreen for Lynch Syndrome (HNPCC).

    PubMed

    Newton, K; Jorgensen, N M; Wallace, A J; Buchanan, D D; Lalloo, F; McMahon, R F T; Hill, J; Evans, D G

    2014-12-01

    Lynch syndrome (LS) patients have DNA mismatch repair deficiency and up to 80% lifetime risk of colorectal cancer (CRC). Screening of mutation carriers reduces CRC incidence and mortality. Selection for constitutional mutation testing relies on family history (Amsterdam and Bethesda Guidelines) and tumour-derived biomarkers. Initial biomarker analysis uses mismatch repair protein immunohistochemistry and microsatellite instability. Abnormalities in either identify mismatch repair deficiency but do not differentiate sporadic epigenetic defects, due to MLH1 promoter region methylation (13% of CRCs) from LS (4% of CRCs). A diagnostic biomarker capable of making this distinction would be valuable. This study compared two biomarkers in tumours with mismatch repair deficiency; quantification of methylation of the MLH1 promoter region using a novel assay and BRAF c.1799T>A, p.(Val600Glu) mutation status in the identification of constitutional mutations. Tumour DNA was extracted (formalin fixed, paraffin embedded, FFPE tissue) and pyrosequencing used to test for MLH1 promoter methylation and presence of the BRAF c.1799T>A, p.(Val600Glu) mutation 71 CRCs from individuals with pathogenic MLH1 mutations and 73 CRCs with sporadic MLH1 loss. Specificity and sensitivity was compared. Unmethylated MLH1 promoter: sensitivity 94.4% (95% CI 86.2% to 98.4%), specificity 87.7% (95% CI 77.9% to 94.2%), Wild-type BRAF (codon 600): sensitivity 65.8% (95% CI 53.7% to 76.5%), specificity 98.6% (95% CI 92.4% to 100.0%) for the identification of those with pathogenic MLH1 mutations. Quantitative MLH1 promoter region methylation using pyrosequencing is superior to BRAF codon 600 mutation status in identifying constitutional mutations in mismatch repair deficient tumours. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  7. Exosomes-mediated transfer of long noncoding RNA ZFAS1 promotes gastric cancer progression.

    PubMed

    Pan, Lei; Liang, Wei; Fu, Min; Huang, Zhen-Hua; Li, Xia; Zhang, Wen; Zhang, Peng; Qian, Hui; Jiang, Peng-Cheng; Xu, Wen-Rong; Zhang, Xu

    2017-06-01

    ZFAS1 is a newly identified long noncoding RNA (lncRNA) that promotes tumor growth and metastasis. Exosomes mediate cellular communications in cancer by transmitting active molecules. The presence of ZFAS1 in the circulating exosomes and the roles of exosomal ZFAS1 in gastric cancer (GC) remains unknown. The aim of this study was to investigate the potential roles of exosomal ZFAS1 in GC. The expression of ZFAS1 was examined in the tumor tissues, serum samples, serum exosomes of GC patients and cell lines using qRT-PCR. The correlation between ZFAS1 expression and the clinicopathological characteristics was analyzed. The characteristics of exosomes were identified using transmission electron microscope (TEM), Nanoparticle Tracking Analysis (NTA), and western blot. The biological roles of ZFAS1 in GC cell growth and mobility were investigated using cell counting, cell colony formation, and transwell migration assay. The potential mechanism of ZFAS1 was demonstrated using flow cytometry, western blot, and qRT-PCR. ZFAS1 expression was elevated in GC cells, tumor tissues, serum and serum exosomes of GC patients. The increased ZFAS1 expression was significantly correlated with lymphatic metastasis and TNM stage. ZFAS1 knockdown inhibited the proliferation and migration of GC cells by suppressing cell cycle progression, inducing apoptosis, and inhibiting epithelial-mesenchymal transition (EMT). On the contrary, ZFAS1 overexpression promoted the proliferation and migration of GC cells. Moreover, ZFAS1 was present in exosomes and could be transmitted by exosomes to enhance GC cell proliferation and migration. ZFAS1 could be delivered by exosomes to promote GC progression, which suggests that ZFAS1 may serve as a potential diagnostic and prognostic biomarker for GC.

  8. FOXO1 promotes wound healing through the up-regulation of TGF-β1 and prevention of oxidative stress

    PubMed Central

    Ponugoti, Bhaskar; Xu, Fanxing; Zhang, Chenying; Tian, Chen; Pacios, Sandra

    2013-01-01

    Keratinocyte mobilization is a critical aspect of wound re-epithelialization, but the mechanisms that control its precise regulation remain poorly understood. We set out to test the hypothesis that forkhead box O1 (FOXO1) has a negative effect on healing because of its capacity to inhibit proliferation and promote apoptosis. Contrary to expectations, FOXO1 is required for keratinocyte transition to a wound-healing phenotype that involves increased migration and up-regulation of transforming growth factor β1 (TGF-β1) and its downstream targets, integrin-α3 and -β6 and MMP-3 and -9. Furthermore, we show that FOXO1 functions in keratinocytes to reduce oxidative stress, which is necessary to maintain cell migration and prevent cell death in a TGF-β1–independent manner. Thus, our studies identify a novel function for FOXO1 in coordinating the response of keratinocytes to wounding through up-regulation of TGF-β1 and other factors needed for keratinocyte migration and protection against oxidative stress, which together promote migration and decrease apoptosis. PMID:24145170

  9. The tumor promoter arsenite stimulates AP-1 activity by inhibiting a JNK phosphatase.

    PubMed Central

    Cavigelli, M; Li, W W; Lin, A; Su, B; Yoshioka, K; Karin, M

    1996-01-01

    Trivalent arsenic (As3+) is highly carcinogenic, but devoid of known mutagenic activity. Therefore, it is likely to act as a tumor promoter. To understand the molecular basis for the tumor-promoting activity of As3+, we examined its effect on transcription factor AP-1, whose activity is stimulated by several other tumor promoters. We found that As3+, but not As5+, which is toxic but not carcinogenic, is a potent stimulator of AP-1 transcriptional activity and an efficient inducer of c-fos and c-jun gene expression. Induction of c-jun and c-fos transcription by As3+ correlates with activation of Jun kinases (JNKs) and p38/Mpk2, which phosphorylate transcription factors that activate these immediate early genes. No effect on ERK activity was observed. As5+, on the other hand, had a negligible effect on JNK or p38/Mpk2 activity. Biochemical analysis and co-transfection experiments strongly suggest that the primary mechanism by which As3+ stimulates JNK activity involves the inhibition of a constitutive dual-specificity JNK phosphatase. This phosphatase activity appears to be responsible for maintaining low basal JNK activity in non-stimulated cells and its inhibition may lead to tumor promotion through induction of proto-oncogenes such as c-jun and c-fos, and stimulation of AP-1 activity. The same phosphatase may also regulate p38/Mpk2 activity. Images PMID:8947050

  10. Peripheral leukocyte expression of the potential biomarker proteins Bdnf, Sirt1, and Psen1 is not regulated by promoter methylation in Alzheimer's disease patients.

    PubMed

    Carboni, Lucia; Lattanzio, Francesca; Candeletti, Sanzio; Porcellini, Elisa; Raschi, Elena; Licastro, Federico; Romualdi, Patrizia

    2015-09-25

    The identification of Alzheimer's disease (AD) biomarkers is crucial to support drug discovery. Within putative biomarkers, peripheral Bdnf levels correlate with cognitive decline and AD, although conflicting findings are reported. Sirtuin 1 (Sirt1) serum levels are lower in AD patients and Presenilin 1 (Psen1) is expressed by blood cells. DNA methylation is altered in AD patients, suggesting that epigenetic mechanisms play a role in AD pathophysiology. The objective of this study was to investigate promoter methylation levels of potential biomarkers in AD cases and controls. Peripheral blood DNA methylation levels were analysed by methylation-specific primer real-time PCR. Bdnf promoter methylation levels did not differ between AD patients and controls. Similarly, Sirt1 promoter revealed minimal levels of methylation which did not display significant differences between groups. No significant difference was revealed between AD patients and controls also in Psen1 methylation, showing a large variability of values among subjects. Although peripheral Bdnf expression is associated with differential promoter methylation in psychiatric and neurological disorders, our results suggest that different mechanisms take place in AD. The finding that the control of Sirt1 protein levels in blood is not exerted through the repression of mRNA expression by promoter hypermethylation is in agreement with previous data. In contrast, other studies reported that Psen1 methylation may be increased or decreased in AD patients, suggesting that additional studies are required. In conclusion, this study shows that peripheral levels of the potential AD biomarker proteins Bdnf, Sirt1, and Psen1 are not regulated by different promoter methylation. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  11. Hypoxia-inducible factor 1–mediated human GATA1 induction promotes erythroid differentiation under hypoxic conditions

    PubMed Central

    Zhang, Feng-Lin; Shen, Guo-Min; Liu, Xiao-Ling; Wang, Fang; Zhao, Ying-Ze; Zhang, Jun-Wu

    2012-01-01

    Abstract Hypoxia-inducible factor promotes erythropoiesis through coordinated cell type–specific hypoxia responses. GATA1 is essential to normal erythropoiesis and plays a crucial role in erythroid differentiation. In this study, we show that hypoxia-induced GATA1 expression is mediated by HIF1 in erythroid cells. Under hypoxic conditions, significantly increased GATA1 mRNA and protein levels were detected in K562 cells and erythroid induction cultures of CD34+ haematopoietic stem/progenitor cells. Enforced HIF1α expression increased GATA1 expression, while HIF1α knockdown by RNA interference decreased GATA1 expression. In silico analysis revealed one potential hypoxia response element (HRE). The results from reporter gene and mutation analysis suggested that this element is necessary for hypoxic response. Chromatin immunoprecipitation (ChIP)-PCR showed that the putative HRE was recognized and bound by HIF1 in vivo. These results demonstrate that the up-regulation of GATA1 during hypoxia is directly mediated by HIF1.The mRNA expression of some erythroid differentiation markers was increased under hypoxic conditions, but decreased with RNA interference of HIF1α or GATA1. Flow cytometry analysis also indicated that hypoxia, desferrioxamine or CoCl2 induced expression of erythroid surface markers CD71 and CD235a, while expression repression of HIF1α or GATA1 by RNA interference led to a decreased expression of CD235a. These results suggested that HIF1-mediated GATA1 up-regulation promotes erythropoiesis in order to satisfy the needs of an organism under hypoxic conditions. PMID:22050843

  12. L1 Peptide-Conjugated Fibrin Hydrogels Promote Salivary Gland Regeneration.

    PubMed

    Nam, K; Wang, C-S; Maruyama, C L M; Lei, P; Andreadis, S T; Baker, O J

    2017-07-01

    Hyposalivation contributes to dental caries, periodontitis, and microbial infections. Additionally, it impairs activities of daily living (e.g., speaking, chewing, and swallowing). Treatments for hyposalivation are currently limited to medications (e.g., the muscarinic receptor agonists pilocarpine and cevimeline) that induce saliva secretion from residual acinar cells and the use of saliva substitutes. However, given that these therapies provide only temporary relief, the development of alternative treatments to restore gland function is essential. Previous studies demonstrated that laminin 1 (L1) is critical for intact salivary cell cluster formation and organization. However, the full L1 sequence is not suitable for clinical applications, as each protein domain may contribute to unwanted effects, such as degradation, tumorigenesis, and immune responses that, when compounded, outweigh the potential benefits provided by their sum. Although the L1 peptides YIGSR and A99 linked to fibrin hydrogels (FHs) promote intact salivary epithelial formation in vitro, little is known about their role during salivary gland regeneration in vivo. Therefore, the goal of this study was to demonstrate whether L1 peptides conjugated to FHs promote tissue regeneration in a wound-healing model of mouse submandibular glands (mSMGs). Our results suggest that YIGSR-A99 peptides, chemically conjugated to FHs and applied to wounded mSMGs in vivo, formed new organized salivary tissue. In contrast, wounded mSMGs treated with FHs alone or in the absence of a scaffold showed disorganized collagen formation and poor tissue healing. Together these studies indicate that damaged salivary gland tissue can grow and differentiate when treated with FHs containing L1 peptides.

  13. Mxi1 is a repressor of the c-Myc promoter and reverses activation by USF.

    PubMed

    Lee, T C; Ziff, E B

    1999-01-08

    The basic region/helix-loop-helix/leucine zipper (B-HLH-LZ) oncoprotein c-Myc is abundant in proliferating cells and forms heterodimers with Max protein that bind to E-box sites in DNA and stimulate genes required for proliferation. A second B-HLH-LZ protein, Mxi1, is induced during terminal differentiation, and forms heterodimers with Max that also bind E-boxes but tether the mSin3 transcriptional repressor protein along with histone deacetylase thereby antagonizing Myc-dependent activation. We show that Mxi1 also antagonizes Myc by a second pathway, repression of transcription from the major c-myc promoter, P2. Repression was independent of Mxi1 binding to mSin3 but dependent on the Mxi1 LZ and COOH-terminal sequences, including putative casein kinase II phosphorylation sites. Repression targeted elements of the myc P2 promoter core (-35/+10), where it reversed transactivation by the constitutive transcription factor, USF. We show that Zn2+ induction of a stably transfected, metallothionein promoter-regulated mxi1 gene blocked the ability of serum to induce transcription of the endogenous c-myc gene and cell entry into S phase. Thus, induction of Mxi1 in terminally differentiating cells may block Myc function by repressing the c-myc gene P2 promoter, as well as by antagonizing Myc-dependent transactivation through E-boxes.

  14. Characterization of promoter of EgPAL1, a novel PAL gene from the oil palm Elaeis guineensis Jacq.

    PubMed

    Yusuf, Chong Yu Lok; Abdullah, Janna Ong; Shaharuddin, Noor Azmi; Abu Seman, Idris; Abdullah, Mohd Puad

    2018-02-01

    The oil palm EgPAL1 gene promoter and its regulatory region were functional as a promoter in the heterologous system of Arabidopsis according to the cis-acting elements present in that region. The promoter was developmentally regulated, vascular tissue specific and responsive to water stress agents. Phenylalanine ammonia lyase (PAL, EC 4.3.1.24) is the key enzyme of the phenylpropanoid pathway which plays important roles in plant development and adaptation. To date, there is no report on the study of PAL from oil palm (Elaeis guineensis), an economically important oil crop. In this study, the 5' regulatory sequence of a highly divergent oil palm PAL gene (EgPAL1) was isolated and fused with GUS in Arabidopsis to create two transgenic plants carrying the minimal promoter with (2302 bp) and without its regulatory elements (139 bp). The regulatory sequence contained cis-acting elements known to be important for plant development and stress response including the AC-II element for lignin biosynthesis and several stress responsive elements. The promoter and its regulatory region were fully functional in Arabidopsis. Its activities were characterised by two common fundamental features of PAL which are responsive to plant internal developmental programme and external factors. The promoter was developmentally regulated in certain organs; highly active in young organs but less active or inactive in mature organs. The presence of the AC elements and global activity of the EgPAL1 promoter in all organs resembled the property of lignin-related genes. The existence of the MBS element and enhancement of the promoter activity by PEG reflected the behaviour of drought-responsive genes. Our findings provide a platform for evaluating oil palm gene promoters in the heterologous system of Arabidopsis and give insights into the activities of EgPAL1 promoter in oil palm.

  15. Sumoylation of Rap1 mediates the recruitment of TFIID to promote transcription of ribosomal protein genes.

    PubMed

    Chymkowitch, Pierre; Nguéa, Aurélie P; Aanes, Håvard; Koehler, Christian J; Thiede, Bernd; Lorenz, Susanne; Meza-Zepeda, Leonardo A; Klungland, Arne; Enserink, Jorrit M

    2015-06-01

    Transcription factors are abundant Sumo targets, yet the global distribution of Sumo along the chromatin and its physiological relevance in transcription are poorly understood. Using Saccharomyces cerevisiae, we determined the genome-wide localization of Sumo along the chromatin. We discovered that Sumo-enriched genes are almost exclusively involved in translation, such as tRNA genes and ribosomal protein genes (RPGs). Genome-wide expression analysis showed that Sumo positively regulates their transcription. We also discovered that the Sumo consensus motif at RPG promoters is identical to the DNA binding motif of the transcription factor Rap1. We demonstrate that Rap1 is a molecular target of Sumo and that sumoylation of Rap1 is important for cell viability. Furthermore, Rap1 sumoylation promotes recruitment of the basal transcription machinery, and sumoylation of Rap1 cooperates with the target of rapamycin kinase complex 1 (TORC1) pathway to promote RPG transcription. Strikingly, our data reveal that sumoylation of Rap1 functions in a homeostatic feedback loop that sustains RPG transcription during translational stress. Taken together, Sumo regulates the cellular translational capacity by promoting transcription of tRNA genes and RPGs. © 2015 Chymkowitch et al.; Published by Cold Spring Harbor Laboratory Press.

  16. The Wnt-1 (int-1) oncogene promoter and its mechanism of activation by insertion of proviral DNA of the mouse mammary tumor virus.

    PubMed Central

    Nusse, R; Theunissen, H; Wagenaar, E; Rijsewijk, F; Gennissen, A; Otte, A; Schuuring, E; van Ooyen, A

    1990-01-01

    Wnt-1 (int-1) is a cellular oncogene often activated by insertion of proviral DNA of the mouse mammary tumor virus. We have mapped the 5' end and the promoter area of the Wnt-1 gene by nuclease protection and primer extension assays. In differentiating P19 embryonal carcinoma cells, in which Wnt-1 is naturally expressed, two start sites of transcription were found, one preceded by two TATA boxes and one preceded by several GC boxes. In P19 cells, a 1-kilobase upstream sequence of Wnt-1 was able to confer differentiation-specific expression on a heterologous gene. We have investigated how Wnt-1 transcription was affected by mouse mammary tumor virus proviral integrations in various configurations near the promoters of the gene. One provirus has been inserted in the 5' nontranslated part of Wnt-1, in the same transcriptional orientation, and has functionally replaced the Wnt-1 promoters. Wnt-1 transcription in this tumor starts in the right long terminal repeat of the provirus, with considerable readthrough transcription from the left long terminal repeat. Another provirus has been inserted in the orientation opposite that of Wnt-1 into a GC box, disrupting the first Wnt-1 transcription start site but not the downstream start site. Most insertions have not structurally altered the Wnt-1 transcripts and have enhanced the activity of the normal two promoters. Images PMID:1695322

  17. miR-4295 promotes cell proliferation and invasion in anaplastic thyroid carcinoma via CDKN1A

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shao, Mingchen; Geng, Yiwei; Laboratory of Tumor Biology, Zhengzhou University, Zhengzhou

    2015-09-04

    MicroRNAs (miRNAs) play important roles in the pathogenesis of many types of cancers by negatively regulating gene expression at posttranscriptional level. However, the role of microRNAs in anaplastic thyroid carcinoma (ATC), has remained elusive. Here, we identified that miR-4295 promotes ATC cell proliferation by negatively regulates its target gene CDKN1A. In ATC cell lines, CCK-8 proliferation assay indicated that the cell proliferation was promoted by miR-4295, while miR-4295 inhibitor significantly inhibited the cell proliferation. Transwell assay showed that miR-4295 mimics significantly promoted the migration and invasion of ATC cells, whereas miR-4295 inhibitors significantly reduced cell migration and invasion. luciferase assaysmore » confirmed that miR-4295 directly bound to the 3'untranslated region of CDKN1A, and western blotting showed that miR-4295 suppressed the expression of CDKN1A at the protein levels. This study indicated that miR-4295 negatively regulates CDKN1A and promotes proliferation and invasion of ATC cell lines. Thus, miR-4295 may represent a potential therapeutic target for ATC intervention. - Highlights: • miR-4295 mimics promote the proliferation and invasion of ATC cells. • miR-4295 inhibitors inhibit the proliferation and invasion of ATC cells. • miR-4295 targets 3′UTR of CDKN1A in ATC cells. • miR-4295 negatively regulates CDKN1A in ATC cells.« less

  18. IRE-1α promotes viral infection by conferring resistance to apoptosis

    PubMed Central

    Fink, Susan L.; Jayewickreme, Teshika R.; Molony, Ryan D.; Iwawaki, Takao; Landis, Charles S.; Lindenbach, Brett D.; Iwasaki, Akiko

    2017-01-01

    The unfolded protein response (UPR) is an ancient cellular pathway that detects and alleviates protein-folding stresses. The UPR components X-box binding protein 1 (XBP1) and inositol-requiring enzyme 1α (IRE1α) promote type I interferon (IFN) responses. Here, we found that Xbp1-deficient mouse embryonic fibroblasts and macrophages had impaired antiviral resistance. Unexpectedly, this was not because of a defect in type I IFN responses, but rather an inability of Xbp1-deficient cells to undergo viral-induced apoptosis. The ability to undergo apoptosis directly limited infection in WT cells. Xbp1-deficient cells were generally resistant to the intrinsic pathway of apoptosis through an indirect mechanism involving activation of the nuclease IRE1α. We observed an IRE1α-dependent reduction in the abundance of the pro-apoptotic microRNA miR-125a, and a corresponding increase in the amounts of the members of the anti-apoptotic Bcl2 family. The activation of IRE1α by the hepatitis C virus (HCV) protein NS4B in Xbp1-proficient cells also conferred apoptosis resistance and promoted viral replication. Furthermore, we found evidence of IRE1α activation and decreased miR-125a abundance in liver biopsies from patients infected with HCV compared to those in the livers of healthy controls. Our results reveal a pro-survival role for IRE1α in virally infected cells, and suggest a possible target for IFN-independent antiviral therapy. PMID:28588082

  19. Targeting the FANCJ–BRCA1 interaction promotes a switch from recombination to polη-dependent bypass

    PubMed Central

    Xie, J; Litman, R; Wang, S; Peng, M; Guillemette, S; Rooney, T; Cantor, SB

    2010-01-01

    BRCA1 and the DNA helicase FANCJ (also known as BACH1 or BRIP1) have common functions in breast cancer suppression and DNA repair. However, the functional significance of the direct interaction between BRCA1 and FANCJ remains unclear. Here, we have discovered that BRCA1 binding to FANCJ regulates DNA damage repair choice. Thus, when FANCJ binding to BRCA1 is ablated, the molecular mechanism chosen for the repair of damaged DNA is dramatically altered. Specifically, a FANCJ protein that cannot be phosphorylated at serine 990 or bind BRCA1 inhibits DNA repair via homologous recombination and promotes polη-dependent bypass. Furthermore, the polη-dependent bypass promoted by FANCJ requires the direct binding to the mismatch repair (MMR) protein, MLH1. Together, our findings implicate that in human cells BRCA1 binding to FANCJ is critical to regulate DNA repair choice and promote genomic stability. Moreover, unregulated FANCJ function could be associated with cancer and/or chemoresistance. PMID:20173781

  20. The mRNA cap-binding protein Cbc1 is required for high and timely expression of genes by promoting the accumulation of gene-specific activators at promoters.

    PubMed

    Li, Tianlu; De Clercq, Nikki; Medina, Daniel A; Garre, Elena; Sunnerhagen, Per; Pérez-Ortín, José E; Alepuz, Paula

    2016-02-01

    The highly conserved Saccharomyces cerevisiae cap-binding protein Cbc1/Sto1 binds mRNA co-transcriptionally and acts as a key coordinator of mRNA fate. Recently, Cbc1 has also been implicated in transcription elongation and pre-initiation complex (PIC) formation. Previously, we described Cbc1 to be required for cell growth under osmotic stress and to mediate osmostress-induced translation reprogramming. Here, we observe delayed global transcription kinetics in cbc1Δ during osmotic stress that correlates with delayed recruitment of TBP and RNA polymerase II to osmo-induced promoters. Interestingly, we detect an interaction between Cbc1 and the MAPK Hog1, which controls most gene expression changes during osmostress, and observe that deletion of CBC1 delays the accumulation of the activator complex Hot1-Hog1 at osmostress promoters. Additionally, CBC1 deletion specifically reduces transcription rates of highly transcribed genes under non-stress conditions, such as ribosomal protein (RP) genes, while having low impact on transcription of weakly expressed genes. For RP genes, we show that recruitment of the specific activator Rap1, and subsequently TBP, to promoters is Cbc1-dependent. Altogether, our results indicate that binding of Cbc1 to the capped mRNAs is necessary for the accumulation of specific activators as well as PIC components at the promoters of genes whose expression requires high and rapid transcription. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Bax Interacting Factor-1 Promotes Survival and Mitochondrial Elongation in Neurons

    PubMed Central

    Wang, David B.; Uo, Takuma; Kinoshita, Chizuru; Sopher, Bryce L.; Lee, Rona J.; Murphy, Sean P.; Kinoshita, Yoshito; Garden, Gwenn A.; Wang, Hong-Gang

    2014-01-01

    Bax-interacting factor 1 (Bif-1, also known as endophilin B1) is a multifunctional protein involved in the regulation of apoptosis, mitochondrial morphology, and autophagy. Previous studies in non-neuronal cells have shown that Bif-1 is proapoptotic and promotes mitochondrial fragmentation. However, the role of Bif-1 in postmitotic neurons has not been investigated. In contrast to non-neuronal cells, we now report that in neurons Bif-1 promotes viability and mitochondrial elongation. In mouse primary cortical neurons, Bif-1 knockdown exacerbated apoptosis induced by the DNA-damaging agent camptothecin. Neurons from Bif-1-deficient mice contained fragmented mitochondria and Bif-1 knockdown in wild-type neurons also resulted in fragmented mitochondria which were more depolarized, suggesting mitochondrial dysfunction. During ischemic stroke, Bif-1 expression was downregulated in the penumbra of wild-type mice. Consistent with Bif-1 being required for neuronal viability, Bif-1-deficient mice developed larger infarcts and an exaggerated astrogliosis response following ischemic stroke. Together, these data suggest that, in contrast to non-neuronal cells, Bif-1 is essential for the maintenance of mitochondrial morphology and function in neurons, and that loss of Bif-1 renders neurons more susceptible to apoptotic stress. These unique actions may relate to the presence of longer, neuron-specific Bif-1 isoforms, because only these forms of Bif-1 were able to rescue deficiencies caused by Bif-1 suppression. This finding not only demonstrates an unexpected role for Bif-1 in the nervous system but this work also establishes Bif-1 as a potential therapeutic target for the treatment of neurological diseases, especially degenerative disorders characterized by alterations in mitochondrial dynamics. PMID:24523556

  2. Silencing of microRNA-138-5p promotes IL-1β-induced cartilage degradation in human chondrocytes by targeting FOXC1: miR-138 promotes cartilage degradation.

    PubMed

    Yuan, Y; Zhang, G Q; Chai, W; Ni, M; Xu, C; Chen, J Y

    2016-10-01

    Osteoarthritis (OA) is characterised by articular cartilage degradation. MicroRNAs (miRNAs) have been identified in the development of OA. The purpose of our study was to explore the functional role and underlying mechanism of miR-138-5p in interleukin-1 beta (IL-1β)-induced extracellular matrix (ECM) degradation of OA cartilage. Human articular cartilage was obtained from patients with and without OA, and chondrocytes were isolated and stimulated by IL-1β. The expression levels of miR-138-5p in cartilage and chondrocytes were both determined. After transfection with miR-138-5p mimics, allele-specific oligonucleotide (ASO)-miR-138-5p, or their negative controls, the messenger RNA (mRNA) levels of aggrecan (ACAN), collagen type II and alpha 1 (COL2A1), the protein levels of glycosaminoglycans (GAGs), and both the mRNA and protein levels of matrix metalloproteinase (MMP)-13 were evaluated. Luciferase reporter assay, quantitative real-time polymerase chain reaction (qRT-PCR), and Western blot were performed to explore whether Forkhead Box C1 (FOCX1) was a target of miR-138-5p. Further, we co-transfected OA chondrocytes with miR-138-5p mimics and pcDNA3.1 (+)-FOXC1 and then stimulated with IL-1β to determine whether miR-138-5p-mediated IL-1β-induced cartilage matrix degradation resulted from targeting FOXC1. MiR-138-5p was significantly increased in OA cartilage and in chondrocytes in response to IL-1β-stimulation. Overexpression of miR-138-5p significantly increased the IL-1β-induced downregulation of COL2A1, ACAN, and GAGs, and increased the IL-1β-induced over expression of MMP-13.We found that FOXC1 is directly regulated by miR-138-5p. Additionally, co-transfection with miR-138-5p mimics and pcDNA3.1 (+)-FOXC1 resulted in higher levels of COL2A1, ACAN, and GAGs, but lower levels of MMP-13. miR-138-5p promotes IL-1β-induced cartilage degradation in human chondrocytes, possibly by targeting FOXC1.Cite this article: Y. Yuan, G. Q. Zhang, W. Chai,M. Ni, C. Xu, J

  3. Mediator subunit MED1 is a T3-dependent and T3-independent coactivator on the thyrotropin β gene promoter

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Matsui, Keiji; Oda, Kasumi; Mizuta, Shumpei

    2013-10-11

    Highlights: •MED1 is a bona fide T3-dependent coactivator on TSHB promoter. •Mice with LxxLL-mutant MED1 have attenuated TSHβ mRNA and thyroid hormone levels. •MED1 activates TSHB promoter T3-dependently in cultured cells. •T3-dependent MED1 action is enhanced when SRC1/SRC2 or HDAC2 is downregulated. •MED1 is also a T3-independent GATA2/Pit1 coactivator on TSHB promoter. -- Abstract: The MED1 subunit of the Mediator transcriptional coregulator complex is a nuclear receptor-specific coactivator. A negative feedback mechanism of thyroid-stimulating hormone (TSH, or thyrotropin) expression in the thyrotroph in the presence of triiodothyronine (T3) is employed by liganded thyroid hormone receptor β (TRβ) on the TSHβmore » gene promoter, where conventional histone-modifying coactivators act as corepressors. We now provide evidence that MED1 is a ligand-dependent positive cofactor on this promoter. TSHβ gene transcription was attenuated in MED1 mutant mice in which the nuclear receptor-binding ability of MED1 was specifically disrupted. MED1 stimulated GATA2- and Pit1-mediated TSHβ gene promoter activity in a ligand-independent manner in cultured cells. MED1 also stimulated transcription from the TSHβ gene promoter in a T3-dependent manner. The transcription was further enhanced when the T3-dependent corepressors SRC1, SRC2, and HDAC2 were downregulated. Hence, MED1 is a T3-dependent and -independent coactivator on the TSHβ gene promoter.« less

  4. COMP-1 promotes competitive advantage of nematode sperm.

    PubMed

    Hansen, Jody M; Chavez, Daniela R; Stanfield, Gillian M

    2015-03-19

    Competition among sperm to fertilize oocytes is a ubiquitous feature of sexual reproduction as well as a profoundly important aspect of sexual selection. However, little is known about the cellular mechanisms sperm use to gain competitive advantage or how these mechanisms are regulated genetically. In this study, we utilize a forward genetic screen in Caenorhabditis elegans to identify a gene, comp-1, whose function is specifically required in competitive contexts. We show that comp-1 functions in sperm to modulate their migration through and localization within the reproductive tract, thereby promoting their access to oocytes. Contrary to previously described models, comp-1 mutant sperm show no defects in size or velocity, thereby defining a novel pathway for preferential usage. Our results indicate not only that sperm functional traits can influence the outcome of sperm competition, but also that these traits can be modulated in a context-dependent manner depending on the presence of competing sperm.

  5. Nac1 promotes self-renewal of embryonic stem cells through direct transcriptional regulation of c-Myc.

    PubMed

    Ruan, Yan; He, Jianrong; Wu, Wei; He, Ping; Tian, Yanping; Xiao, Lan; Liu, Gaoke; Wang, Jiali; Cheng, Yuda; Zhang, Shuo; Yang, Yi; Xiong, Jiaxiang; Zhao, Ke; Wan, Ying; Huang, He; Zhang, Junlei; Jian, Rui

    2017-07-18

    The pluripotency transcriptional network in embryonic stem cells (ESCs) is composed of distinct functional units including the core and Myc units. It is hoped that dissection of the cellular functions and interconnections of network factors will aid our understanding of ESC and cancer biology. Proteomic and genomic approaches have identified Nac1 as a member of the core pluripotency network. However, previous studies have predominantly focused on the role of Nac1 in psychomotor stimulant response and cancer pathogenesis. In this study, we report that Nac1 is a self-renewal promoting factor, but is not required for maintaining pluripotency of ESCs. Loss of function of Nac1 in ESCs results in a reduced proliferation rate and an enhanced differentiation propensity. Nac1 overexpression promotes ESC proliferation and delays ESC differentiation in the absence of leukemia inhibitory factor (LIF). Furthermore, we demonstrated that Nac1 directly binds to the c-Myc promoter and regulates c-Myc transcription. The study also revealed that the function of Nac1 in promoting ESC self-renewal appears to be partially mediated by c-Myc. These findings establish a functional link between the core and c-Myc-centered networks and provide new insights into mechanisms of stemness regulation in ESCs and cancer.

  6. Actin microfilaments participate in the regulation of the COL1A1 promoter activity in ROS17/2.8 cells under simulated microgravity

    NASA Astrophysics Data System (ADS)

    Dai, Zhongquan; Li, Yinghui; Ding, Bai; Zhang, Xiaoyou; Tan, Yingjun; Wan, Yumin

    2006-01-01

    IntroductionMicrogravity is thought to decrease osteoblastic activity and induce osteoporosis during spaceflight, but the mechanisms, particularly the attendant changes in gene expression, are not well understood. It is suspected that the cytoskeletal system is involved in the manifold changes of cell shape, function, and signaling under microgravity conditions. MethodsWe constructed cell lines stably transfected with pJI36EGFP and pJI23EGFP, which contained a 3.6 and a 2.3 kb fragment, respectively, of the α1(I) collagen gene (COL1A1) promoter fused with the enhanced green fluorescence protein (EGFP) reporter gene. We then developed a semi-quantitative analysis of EGFP fluorescence intensity to evaluate the effects of clinorotation and/or cytochalasin B on the activity of the COL1A1 promoter. Simultaneously, we assessed the collagen type I protein content versus total protein content in clinorotated or control osteoblasts, using immunocytochemistry and the Bradford method, respectively. ResultsThe fluorescence intensity analysis revealed that the expression of COL1A1-EGFP increased in GFP-ROS cells clinorotated for 24 or 48 h, as compared with stationary control cultures. We observed a similar trend in collagen type I content, as assessed by immunocytochemistry. We found that the osteoblast microfilaments tended to disassemble and show a reduction in stress fibers under space flight and clinorotation. Treatment with cytochalasin B in normal gravity resulted in a dose-dependent increase of EGFP fluorescence intensity, indicating that disruption of the actin system was associated with increased activity of the COL1A1 promoter. ConclusionOur study demonstrates that disrupting the actin cytoskeleton by treatment with cytochalasin B and real or simulated microgravity conditions led to altered COL1A1 promoter activity. Together, these results suggest that actin may participate in the regulation of the COL1A1 promoter activity under microgravity conditions.

  7. A strategy for promoting astaxanthin accumulation in Haematococcus pluvialis by 1-aminocyclopropane-1-carboxylic acid application.

    PubMed

    Lee, Changsu; Choi, Yoon-E; Yun, Yeoung-Sang

    2016-10-20

    The green algae Haematococcus pluvialis is a freshwater unicellular microalga belonging to Chlorophyceae. It is one of the best natural sources of astaxanthin, a secondary metabolite commonly used as an antioxidant and anti-inflammatory agent. Due to the importance of astaxanthin, various efforts have been made to increase its production. In this study, we attempted to develop a strategy for promoting astaxanthin accumulation in H. pluvialis using 1-aminocyclopropane-1-carboxylic acid (ACC), a precursor of ethylene (normally known as an aging hormone in plants). Our results demonstrated that ACC could enhance the growth of H. pluvialis, thereby promoting astaxanthin accumulation. Therefore, ACC has an indirect influence on astaxanthin production. We further verified the effect of ACC with a direct treatment of ethylene originated from banana peels. These results indicate that ethylene could be applied as an indirect method for enhancing growth and astaxanthin biosynthesis in H. pluvialis. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Dystroglycan modulates the ability of insulin-like growth factor-1 to promote oligodendrocyte differentiation.

    PubMed

    Galvin, Jason; Eyermann, Christopher; Colognato, Holly

    2010-11-15

    The adhesion receptor dystroglycan positively regulates terminal differentiation of oligodendrocytes, but the mechanism by which this occurs remains unclear. Using primary oligodendrocyte cultures, we identified and examined a connection between dystroglycan and the ability of insulin-like growth factor-1 (IGF-1) to promote oligodendrocyte differentiation. Consistent with previous reports, treatment with exogenous IGF-1 caused an increase in MBP protein that was preceded by activation of PI3K (AKT) and MAPK (ERK) signaling pathways. The extracellular matrix protein laminin was further shown to potentiate the effect of IGF-1 on oligodendrocyte differentiation. Depletion of the laminin receptor dystroglycan using siRNA, however, blocked the ability of IGF-1 to promote oligodendrocyte differentiation of cells grown on laminin, suggesting a role for dystroglycan in IGF-1-mediated differentiation. Indeed, loss of dystroglycan led to a reduction in the ability of IGF-1 to activate MAPK, but not PI3K, signaling pathways. Pharmacological inhibition of MAPK signaling also prevented IGF-1-induced increases in myelin basic protein (MBP), indicating that MAPK signaling was necessary to drive IGF-1-mediated enhancement of oligodendrocyte differentiation. Using immunoprecipitation, we found that dystroglycan, the adaptor protein Grb2, and insulin receptor substrate-1 (IRS-1), were associated in a protein complex. Taken together, our results suggest that the positive regulatory effect of laminin on oligodendrocyte differentiation may be attributed, at least in part, to dystroglycan's ability to promote IGF-1-induced differentiation.

  9. Differential utilization of TATA box-binding protein (TBP) and TBP-related factor 1 (TRF1) at different classes of RNA polymerase III promoters.

    PubMed

    Verma, Neha; Hung, Ko-Hsuan; Kang, Jin Joo; Barakat, Nermeen H; Stumph, William E

    2013-09-20

    In the fruit fly Drosophila melanogaster, RNA polymerase III transcription was found to be dependent not upon the canonical TATA box-binding protein (TBP) but instead upon the TBP-related factor 1 (TRF1) (Takada, S., Lis, J. T., Zhou, S., and Tjian, R. (2000) Cell 101, 459-469). Here we confirm that transcription of fly tRNA genes requires TRF1. However, we unexpectedly find that U6 snRNA gene promoters are occupied primarily by TBP in cells and that knockdown of TBP, but not TRF1, inhibits U6 transcription in cells. Moreover, U6 transcription in vitro effectively utilizes TBP, whereas TBP cannot substitute for TRF1 to promote tRNA transcription in vitro. Thus, in fruit flies, different classes of RNA polymerase III promoters differentially utilize TBP and TRF1 for the initiation of transcription.

  10. TOR Signaling Promotes Accumulation of BZR1 to Balance Growth with Carbon Availability in Arabidopsis.

    PubMed

    Zhang, Zhenzhen; Zhu, Jia-Ying; Roh, Jeehee; Marchive, Chloé; Kim, Seong-Ki; Meyer, Christian; Sun, Yu; Wang, Wenfei; Wang, Zhi-Yong

    2016-07-25

    For maintenance of cellular homeostasis, the actions of growth-promoting hormones must be attenuated when nutrient and energy become limiting. The molecular mechanisms that coordinate hormone-dependent growth responses with nutrient availability remain poorly understood in plants [1, 2]. The target of rapamycin (TOR) kinase is an evolutionarily conserved master regulator that integrates nutrient and energy signaling to regulate growth and homeostasis in both animals and plants [3-7]. Here, we show that sugar signaling through TOR controls the accumulation of the brassinosteroid (BR)-signaling transcription factor BZR1, which is essential for growth promotion by multiple hormonal and environmental signals [8-11]. Starvation, caused by shifting of light-grown Arabidopsis seedlings into darkness, as well as inhibition of TOR by inducible RNAi, led to plant growth arrest and reduced expression of BR-responsive genes. The growth arrest caused by TOR inactivation was partially recovered by BR treatment and the gain-of-function mutation bzr1-1D, which causes accumulation of active forms of BZR1 [12]. Exogenous sugar promoted BZR1 accumulation and seedling growth, but such sugar effects were largely abolished by inactivation of TOR, whereas the effect of TOR inactivation on BZR1 degradation is abolished by inhibition of autophagy and by the bzr1-1D mutation. These results indicate that cellular starvation leads sequentially to TOR inactivation, autophagy, and BZR1 degradation. Such regulation of BZR1 accumulation by glucose-TOR signaling allows carbon availability to control the growth promotion hormonal programs, ensuring supply-demand balance in plant growth. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. O-GlcNAcylation of RACK1 promotes hepatocellular carcinogenesis.

    PubMed

    Duan, Fangfang; Wu, Hao; Jia, Dongwei; Wu, Weicheng; Ren, Shifang; Wang, Lan; Song, Shushu; Guo, Xinying; Liu, Fenglin; Ruan, Yuanyuan; Gu, Jianxin

    2018-06-01

    Aberrant oncogenic mRNA translation and protein O-linked β-N-acetylglucosaminylation (O-GlcNAcylation) are general features during tumorigenesis. Nevertheless, whether and how these two pathways are interlinked remain unknown. Our previous study indicated that ribosomal receptor for activated C-kinase 1 (RACK1) promoted chemoresistance and growth in hepatocellular carcinoma (HCC). The aim of this study is to examine the role of RACK1 O-GlcNAcylation in oncogene translation and HCC carcinogenesis. The site(s) of RACK1 for O-GlcNAcylation was mapped by mass spectrometry analysis. HCC cell lines were employed to examine the effects of RACK1 O-GlcNAcylation on the translation of oncogenic factors and behaviors of tumor cells in vitro. Transgenic knock-in mice were used to detect the role of RACK1 O-GlcNAcylation in modulating HCC tumorigenesis in vivo. The correlation of RACK1 O-GlcNAcylation with tumor progression and relapse were analyzed in clinical HCC samples. We found that ribosomal RACK1 was highly modified by O-GlcNAc at Ser122. O-GlcNAcylation of RACK1 enhanced its protein stability, ribosome binding and interaction with PKCβII (PRKCB), leading to increased eukaryotic translation initiation factor 4E phosphorylation and translation of potent oncogenes in HCC cells. Genetic ablation of RACK1 O-GlcNAcylation at Ser122 dramatically suppressed tumorigenesis, angiogenesis, and metastasis in vitro and in diethylnitrosamine (DEN)-induced HCC mouse model. Increased RACK1 O-GlcNAcylation was also observed in HCC patient samples and correlated with tumor development and recurrence after chemotherapy. These findings demonstrate that RACK1 acts as key mediator linking O-GlcNAc metabolism to cap-dependent translation during HCC tumorigenesis. Targeting RACK1 O-GlcNAcylation provides promising options for HCC treatment. O-GlcNAcylation of ribosomal receptor for activated C-kinase 1 at the amino acid serine122 promotes its stability, ribosome localization and interaction

  12. EMP-1 promotes tumorigenesis of NSCLC through PI3K/AKT pathway.

    PubMed

    Lai, Senyan; Wang, Guihua; Cao, Xiaonian; Li, Zhaoming; Hu, Junbo; Wang, Jing

    2012-12-01

    This study examined the role of EMP-1 in tumorigenesis of non-small cell lung carcinoma (NSCLC) and the possible mechanism. Specimens were collected from 28 patients with benign lung diseases and 28 with NSCLC, and immunohistochemically detected to evaluate the correlation of EMP-1 expression to the clinical features of NSCLC. Recombinant adenovirus was constructed to over-express EMP-1 and then infect PC9 cells. Cell proliferation was measured by Ki67 staining. Western blotting was performed to examine the effect of EMP-1 on the PI3K/AKT signaling. Moreover, tumor xenografts were established by subcutaneous injection of PC9 cell suspension (about 5×10(7)/mL in 100 μL of PBS) into the right hind limbs of athymic nude mice. The results showed EMP-1 was significantly up-regulated in NSCLC patients as compared with those with benign lung diseases. Over-expression of EMP-1 promoted proliferation of PC9 cells, which coincided with the activation of the PI3K/AKT pathway. EMP-1 promoted the growth of xenografts of PC9 cells in athymic nude mice. It was concluded that EMP-1 expression may contribute to the development and progress of NSCLC by activating PI3K/AKT pathway.

  13. AMPK activation represses the human gene promoter of the cardiac isoform of acetyl-CoA carboxylase: Role of nuclear respiratory factor-1

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Adam, Tasneem; Opie, Lionel H.; Essop, M. Faadiel, E-mail: mfessop@sun.ac.za

    Research highlights: {yields} AMPK inhibits acetyl-CoA carboxylase beta gene promoter activity. {yields} Nuclear respiratory factor-1 inhibits acetyl-CoA carboxylase beta promoter activity. {yields} AMPK regulates acetyl-CoA carboxylase beta at transcriptional level. -- Abstract: The cardiac-enriched isoform of acetyl-CoA carboxylase (ACC{beta}) produces malonyl-CoA, a potent inhibitor of carnitine palmitoyltransferase-1. AMPK inhibits ACC{beta} activity, lowering malonyl-CoA levels and promoting mitochondrial fatty acid {beta}-oxidation. Previously, AMPK increased promoter binding of nuclear respiratory factor-1 (NRF-1), a pivotal transcriptional modulator controlling gene expression of mitochondrial proteins. We therefore hypothesized that NRF-1 inhibits myocardial ACC{beta} promoter activity via AMPK activation. A human ACC{beta} promoter-luciferase construct was transientlymore » transfected into neonatal cardiomyocytes {+-} a NRF-1 expression construct. NRF-1 overexpression decreased ACC{beta} gene promoter activity by 71 {+-} 4.6% (p < 0.001 vs. control). Transfections with 5'-end serial promoter deletions revealed that NRF-1-mediated repression of ACC{beta} was abolished with a pPII{beta}-18/+65-Luc deletion construct. AMPK activation dose-dependently reduced ACC{beta} promoter activity, while NRF-1 addition did not further decrease it. We also investigated NRF-1 inhibition in the presence of upstream stimulatory factor 1 (USF1), a known transactivator of the human ACC{beta} gene promoter. Here NRF-1 blunted USF1-dependent induction of ACC{beta} promoter activity by 58 {+-} 7.5% (p < 0.001 vs. control), reversed with a dominant negative NRF-1 construct. NRF-1 also suppressed endogenous USF1 transcriptional activity by 55 {+-} 6.2% (p < 0.001 vs. control). This study demonstrates that NRF-1 is a novel transcriptional inhibitor of the human ACC{beta} gene promoter in the mammalian heart. Our data extends AMPK regulation of ACC{beta} to the transcriptional

  14. One-pot microwave assisted stereoselective synthesis of novel dihydro-2'H-spiro[indene-2,1'-pyrrolo-[3,4-c]pyrrole]-tetraones and evaluation of their antimycobacterial activity and inhibition of AChE.

    PubMed

    Bharkavi, Chelliah; Vivek Kumar, Sundaravel; Ashraf Ali, Mohamed; Osman, Hasnah; Muthusubramanian, Shanmugam; Perumal, Subbu

    2017-07-15

    An efficient one-pot microwave assisted stereoselective synthesis of novel dihydro-2'H-spiro[indene-2,1'-pyrrolo[3,4-c]pyrrole]-tetraone derivatives through three-component 1,3-dipolar cycloaddition of azomethine ylides generated in situ from ninhydrin and sarcosine with a series of 1-aryl-1H-pyrrole-2,5-diones is described. The synthesised compounds were screened for their antimycobacterial and AChE inhibition activities. Compound 4b (IC 50 1.30µM) has been found to display twelve fold antimycobacterial activity compared to cycloserine and it is thirty seven times more active than pyrimethamine. Compound 4h displays maximum AchE inhibitory activity with IC 50 value of 0.78±0.01µmol/L. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Ascophyllan Purified from Ascophyllum nodosum Induces Th1 and Tc1 Immune Responses by Promoting Dendritic Cell Maturation

    PubMed Central

    Zhang, Wei; Du, Jiang-Yuan; Jiang, Zedong; Okimura, Takasi; Oda, Tatsuya; Yu, Qing; Jin, Jun-O

    2014-01-01

    Marine-derived sulfated polysaccharides have been shown to possess certain anti-virus, anti-tumor, anti-inflammatory and anti-coagulant activities. However, the in vivo immunomodulatory effects of marine-derived pure compounds have been less well characterized. In this study, we investigated the effect of ascophyllan, a sulfated polysaccharide purified from Ascophyllum nodosum, on the maturation of mouse dendritic cells (DCs) in vitro and in vivo. Ascophyllan induced up-regulation of co-stimulatory molecules and production of pro-inflammatory cytokines in bone marrow-derived DCs (BMDCs). Moreover, in vivo administration of ascophyllan promotes up-regulation of CD40, CD80, CD86, MHC class I and MHC class II and production of IL-6, IL-12 and TNF-α in spleen cDCs. Interestingly, ascophyllan induced a higher degree of co-stimulatory molecule up-regulation and pro-inflammatory cytokine production than fucoidan, a marine-derived polysaccharide with well-defined effect for promoting DC maturation. Ascophyllan also promoted the generation of IFN-γ-producing Th1 and Tc1 cells in the presence of DCs in an IL-12-dependent manner. Finally, myeloid differentiation primary response 88 (MyD88) signaling pathway was essential for DC maturation induced by ascophyllan. Taken together, these results demonstrate that ascophyllan induces DC maturation, and consequently enhances Th1 and Tc1 responses in vivo. This knowledge could facilitate the development of novel therapeutic strategies to combat infectious diseases and cancer. PMID:25026264

  16. Phlpp1 facilitates post-traumatic osteoarthritis and is induced by inflammation and promoter demethylation in human osteoarthritis

    PubMed Central

    Bradley, Elizabeth W.; Carpio, Lomeli R.; McGee-Lawrence, Meghan E.; Becerra, Clara Castillejo; Amanatullah, Derek F.; Ta, Lauren E.; Otero, Miguel; Goldring, Mary B.; Kakar, Sanjeev; Westendorf, Jennifer J.

    2016-01-01

    OBJECTIVE Osteoarthritis (OA) is the most common form of arthritis and a leading cause of disability. OA is characterized by articular chondrocyte deterioration, subchondral bone changes and debilitating pain. One strategy to promote cartilage regeneration and repair is to accelerate proliferation and matrix production of articular chondrocytes. We previously reported that the protein phosphatase Phlpp1 controls chondrocyte differentiation by regulating the activities of anabolic kinases. Here we examined the role of Phlpp1 in osteoarthritis progression in a murine model. We also assessed PHLPP1 expression and promoter methylation. DESIGN Knee joints of WT and Phlpp1−/− mice were surgically destabilized by transection of the medial meniscal ligament (DMM). Mice were assessed for signs of OA progression via radiographic and histological analyses, and pain assessment for mechanical hypersensitivity using the von Frey assay. Methylation of the PHLPP1 promoter and PHLPP1 expression was evaluated in human articular cartilage and chondrocyte cell lines. RESULTS Following DMM surgeries, Phlpp1 deficient mice showed fewer signs of OA and cartilage degeneration. Mechanical allodynia associated with DMM surgeries was also attenuated in Phlpp1−/− mice. PHLPP1 was highly expressed in human articular cartilage from OA patients, but was undetectable in cartilage specimens from femoral neck fractures. Higher PHLPP1 levels correlated with less PHLPP1 promoter CpG methylation in cartilage from OA patients. Blocking cytosine methylation or treatment with inflammatory mediators enhanced PHLPP1 expression in human chondrocyte cell lines. CONCLUSION Phlpp1 deficiency protects against OA progression while CpG demethylation and inflammatory responses promote PHLPP1 expression. PMID:26746148

  17. Regulation of the intronic promoter of rat estrogen receptor alpha gene, responsible for truncated estrogen receptor product-1 expression.

    PubMed

    Schausi, Diane; Tiffoche, Christophe; Thieulant, Marie-Lise

    2003-07-01

    We have characterized the intronic promoter of the rat estrogen receptor (ER) alpha gene, responsible for the lactotrope-specific truncated ER product (TERP)-1 isoform expression. Transcriptional regulation was investigated by transient transfections using 5'-deletion constructs. TERP promoter constructs were highly active in MMQ cells, a pure lactotrope cell line, whereas a low basal activity was detected in alphaT3-1 gonadotrope cells or in COS-7 monkey kidney cells. Serial deletion analysis revealed that 1) a minimal -693-bp region encompassing the TATA box is sufficient to allow lactotrope-specific expression; 2) the promoter contains strong positive cis-acting elements both in the distal and proximal regions, and 3) the region spanning the -1698/-1194 region includes repressor elements. Transient transfection studies, EMSAs, and gel shifts demonstrated that estrogen activates the TERP promoter via an estrogen-responsive element (ERE1) located within the proximal region. Mutation of ERE1 site completely abolishes the estradiol-dependent transcription, indicating that ERE1 site is sufficient to confer estrogen responsiveness to TERP promoter. In addition, ERalpha action was synergized by transfection of the pituitary-specific factor Pit-1. EMSAs showed that a single Pit-1 DNA binding element in the vicinity of the TATA box is sufficient to confer response by the TERP promoter. In conclusion, we demonstrated, for the first time, that TERP promoter regulation involves ERE and Pit-1 cis-elements and corresponding trans-acting factors, which could play a role in the physiological changes that occur in TERP-1 transcription in lactotrope cells.

  18. Activation of stress response gene SIRT1 by BCR-ABL promotes leukemogenesis

    PubMed Central

    Yuan, Hongfeng; Wang, Zhiqiang; Li, Ling; Zhang, Hao; Modi, Hardik; Horne, David

    2012-01-01

    The tyrosine kinase inhibitor imatinib is highly effective in the treatment of chronic myelogenous leukemia (CML), but primary and acquired resistance of CML cells to the drug offset its efficacy. Molecular mechanisms for resistance of CML to tyrosine kinase inhibitors are not fully understood. In the present study, we show that BCR-ABL activates the expression of the mammalian stress response gene SIRT1 in hematopoietic progenitor cells and that this involves STAT5 signaling. SIRT1 activation promotes CML cell survival and proliferation associated with deacetylation of multiple SIRT1 substrates, including FOXO1, p53, and Ku70. Imatinib-mediated inhibition of BCR-ABL kinase activity partially reduces SIRT1 expression and SIRT1 inhibition further sensitizes CML cells to imatinib-induced apoptosis. Knockout of SIRT1 suppresses BCR-ABL transformation of mouse BM cells and the development of a CML-like myeloproliferative disease, and treatment of mice with the SIRT1 inhibitor tenovin-6 deters disease progression. The combination of SIRT1 gene knockout and imatinib treatment further extends the survival of CML mice. Our results suggest that SIRT1 is a novel survival pathway activated by BCR-ABL expression in hematopoietic progenitor cells, which promotes oncogenic transformation and leukemogenesis. Our findings suggest further exploration of SIRT1 as a therapeutic target for CML treatment to overcome resistance. PMID:22207735

  19. Human hnRNP protein A1 gene expression. Structural and functional characterization of the promoter.

    PubMed

    Biamonti, G; Bassi, M T; Cartegni, L; Mechta, F; Buvoli, M; Cobianchi, F; Riva, S

    1993-03-05

    hnRNP protein A1 (34 kDa, pl 9.5) is a prominent member of the family of proteins (hnRNP proteins) that associate with the nascent transcripts of RNA polymerase II and that accompany the hnRNA through the maturation process and the export to the cytoplasm. New evidence suggests an active and specific role for some of these proteins, including protein A1, in splicing and transport. Contrary to the other hnRNP proteins, the intracellular level of protein A1 was reported to change as a function of proliferation state and cell type. In this work we analyse the A1 gene expression in different cells under different growth and differentiation conditions. Proliferation dependent expression was observed in lymphocytes and fibroblasts while purified neurons express high A1 mRNA levels both in the proliferative (before birth) and in the quiescent (after birth) state. Transformed cell lines exhibit very high (proliferation independent) A1 mRNA levels compared to differentiated tissues. A structural and functional characterization of the A1 gene promoter was carried out by means of DNase I footprinting and CAT assays. The observed promoter features can account for both elevated and regulated mRNA transcription. At least 12 control elements are contained in the 734 nucleotides upstream of the transcription start site. Assays with the deleted and/or mutated promoter indicate a co-operation of multiple transcriptional elements, distributed over the entire promoter, in determining the overall activity and the response to proliferative stimuli (serum).

  20. The interaction between NOLC1 and IAV NS1 protein promotes host cell apoptosis and reduces virus replication.

    PubMed

    Zhu, Chunyu; Zheng, Fangliang; Zhu, Junfeng; Liu, Meichen; Liu, Na; Li, Xue; Zhang, Li; Deng, Zaidong; Zhao, Qi; Liu, Hongsheng

    2017-11-07

    NS1 of the influenza virus plays an important role in the infection ability of the influenza virus. Our previous research found that NS1 protein interacts with the NOLC1 protein of host cells, however, the function of the interaction is unknown. In the present study, the role of the interaction between the two proteins in infection was further studied. Several analyses, including the use of a pull-down assay, Co-IP, western blot analysis, overexpression, RNAi, flow cytometry, etc., were used to demonstrate that the NS1 protein of H3N2 influenza virus interacts with host protein NOLC1 and reduces the quantity of NOLC1. The interaction also promotes apoptosis in A549 host cells, while the suppression of NOLC1 protein reduces the proliferation of the H3N2 virus. Based on these data, it was concluded that during the process of infection, NS1 protein interacts with NOLC1 protein, reducing the level of NOLC1, and that the interaction between the two proteins promotes apoptosis of host cells, thus reducing the proliferation of the virus. These findings provide new information on the biological function of the interaction between NS1 and NOLC1.

  1. Estrogen and progesterone promote breast cancer cell proliferation by inducing cyclin G1 expression.

    PubMed

    Tian, J-M; Ran, B; Zhang, C-L; Yan, D-M; Li, X-H

    2018-01-23

    Breast cancer is the most common cause of cancer among women in most countries (WHO). Ovarian hormone disorder is thought to be associated with breast tumorigenesis. The present study investigated the effects of estrogen and progesterone administration on cell proliferation and underlying mechanisms in breast cancer MCF-7 cells. It was found that a single administration of estradiol (E2) or progesterone increased MCF-7 cell viability in a dose-dependent manner and promoted cell cycle progression by increasing the percentage of cells in the G2/M phase. A combination of E2 and progesterone led to a stronger effect than single treatment. Moreover, cyclin G1 was up-regulated by E2 and/or progesterone in MCF-7 cells. After knockdown of cyclin G1 in MCF-7 cells using a specific shRNA, estradiol- and progesterone-mediated cell viability and clonogenic ability were significantly limited. Additionally, estradiol- and progesterone-promoted cell accumulation in the G2/M phase was reversed after knockdown of cyclin G1. These data indicated that estrogen and progesterone promoted breast cancer cell proliferation by inducing the expression of cyclin G1. Our data indicated that novel therapeutics against cyclin G1 are promising for the treatment of estrogen- and progesterone-mediated breast cancer progression.

  2. An ABA-responsive element in the AtSUC1 promoter is involved in the regulation of AtSUC1 expression.

    PubMed

    Hoth, Stefan; Niedermeier, Matthias; Feuerstein, Andrea; Hornig, Julia; Sauer, Norbert

    2010-09-01

    Abscisic acid (ABA) and sugars regulate many aspects of plant growth and development, and we are only just beginning to understand the complex interactions between ABA and sugar signaling networks. Here, we show that ABA-dependent transcription factors bind to the promoter of the Arabidopsis thaliana AtSUC1 (At1g71880) sucrose transporter gene in vitro. We present the characterization of a cis-regulatory element by truncation of the AtSUC1 promoter and by electrophoretic mobility shift assays that is identical to a previously characterized ABA-responsive element (ABRE). In yeast 1-hybrid analyses we identified ABI5 (AtbZIP39; At2g36270) and AREB3 (AtbZIP66; At3g56850) as potential interactors. Analyses of plants expressing the beta-glucuronidase reporter gene under the control of ABI5 or AREB3 promoter sequences demonstrated that both transcription factor genes are co-expressed with AtSUC1 in pollen and seedlings, the primary sites of AtSUC1 action. Mutational analyses of the identified cis-regulatory element verified its importance for AtSUC1 expression in young seedlings. In abi5-4 seedlings, we observed an increase of sucrose-dependent anthocyanin accumulation and AtSUC1 mRNA levels. This suggests that ABI5 prevents an overshoot of sucrose-induced AtSUC1 expression and confirmed a novel cross-link between sugar and ABA signaling.

  3. Lissencephaly-1 promotes the recruitment of dynein and dynactin to transported mRNAs

    PubMed Central

    Dix, Carly I.; Soundararajan, Harish Chandra; Dzhindzhev, Nikola S.; Begum, Farida; Suter, Beat; Ohkura, Hiroyuki; Stephens, Elaine

    2013-01-01

    Microtubule-based transport mediates the sorting and dispersal of many cellular components and pathogens. However, the mechanisms by which motor complexes are recruited to and regulated on different cargos remain poorly understood. Here we describe a large-scale biochemical screen for novel factors associated with RNA localization signals mediating minus end–directed mRNA transport during Drosophila development. We identified the protein Lissencephaly-1 (Lis1) and found that minus-end travel distances of localizing transcripts are dramatically reduced in lis1 mutant embryos. Surprisingly, given its well-documented role in regulating dynein mechanochemistry, we uncovered an important requirement for Lis1 in promoting the recruitment of dynein and its accessory complex dynactin to RNA localization complexes. Furthermore, we provide evidence that Lis1 levels regulate the overall association of dynein with dynactin. Our data therefore reveal a critical role for Lis1 within the mRNA localization machinery and suggest a model in which Lis1 facilitates motor complex association with cargos by promoting the interaction of dynein with dynactin. PMID:23918939

  4. Human FAN1 promotes strand incision in 5'-flapped DNA complexed with RPA.

    PubMed

    Takahashi, Daisuke; Sato, Koichi; Hirayama, Emiko; Takata, Minoru; Kurumizaka, Hitoshi

    2015-09-01

    Fanconi anaemia (FA) is a human infantile recessive disorder. Seventeen FA causal proteins cooperatively function in the DNA interstrand crosslink (ICL) repair pathway. Dual DNA strand incisions around the crosslink are critical steps in ICL repair. FA-associated nuclease 1 (FAN1) is a DNA structure-specific endonuclease that is considered to be involved in DNA incision at the stalled replication fork. Replication protein A (RPA) rapidly assembles on the single-stranded DNA region of the stalled fork. However, the effect of RPA on the FAN1-mediated DNA incision has not been determined. In this study, we purified human FAN1, as a bacterially expressed recombinant protein. FAN1 exhibited robust endonuclease activity with 5'-flapped DNA, which is formed at the stalled replication fork. We found that FAN1 efficiently promoted DNA incision at the proper site of RPA-coated 5'-flapped DNA. Therefore, FAN1 possesses the ability to promote the ICL repair of 5'-flapped DNA covered by RPA. © The Authors 2015. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

  5. A core functional region of the RFP1 promoter from Chinese wild grapevine is activated by powdery mildew pathogen and heat stress.

    PubMed

    Yu, Yihe; Xu, Weirong; Wang, Jie; Wang, Lei; Yao, Wenkong; Xu, Yan; Ding, Jiahua; Wang, Yuejin

    2013-01-01

    RING-finger proteins (RFP) function as ubiquitin ligases and play key roles in plant responses to biotic and abiotic stresses. However, little information is available on the regulation of RFP expression. Here, we isolate and characterize the RFP promoter sequence from the disease-resistant Chinese wild grape Vitis pseudoreticulata accession Baihe-35-1. Promoter-GUS fusion assays revealed that defense signaling molecules, powdery mildew infection, and heat stress induce VpRFP1 promoter activity. By contrast, the RFP1 promoter isolated from Vitis vinifera was only slightly induced by pathogen infection and heat treatment. By promoter deletion analysis, we found that the -148 bp region of the VpRFP1 promoter was the core functional promoter region. We also found that, in Arabidopsis, VpRFP1 expressed under its own promoter activated defense-related gene expression and improved disease resistance, but the same construct using the VvRFP1 promoter slightly improve disease resistance. Our results demonstrated that the -148 bp region of the VpRFP1 promoter plays a key role in response to pathogen and heat stress, and suggested that expression differences between VpRFP1 and VvRFP1 may be key for the differing disease resistance phenotypes of the two Vitis genotypes.

  6. Rab-coupling protein coordinates recycling of alpha5beta1 integrin and EGFR1 to promote cell migration in 3D microenvironments.

    PubMed

    Caswell, Patrick T; Chan, May; Lindsay, Andrew J; McCaffrey, Mary W; Boettiger, David; Norman, Jim C

    2008-10-06

    Here we show that blocking the adhesive function of alphavbeta3 integrin with soluble RGD ligands, such as osteopontin or cilengitide, promoted association of Rab-coupling protein (RCP) with alpha5beta1 integrin and drove RCP-dependent recycling of alpha5beta1 to the plasma membrane and its mobilization to dynamic ruffling protrusions at the cell front. These RCP-driven changes in alpha5beta1 trafficking led to acquisition of rapid/random movement on two-dimensional substrates and to a marked increase in fibronectin-dependent migration of tumor cells into three-dimensional matrices. Recycling of alpha5beta1 integrin did not affect its regulation or ability to form adhesive bonds with substrate fibronectin. Instead, alpha5beta1 controlled the association of EGFR1 with RCP to promote the coordinate recycling of these two receptors. This modified signaling downstream of EGFR1 to increase its autophosphorylation and activation of the proinvasive kinase PKB/Akt. We conclude that RCP provides a scaffold that promotes the physical association and coordinate trafficking of alpha5beta1 and EGFR1 and that this drives migration of tumor cells into three-dimensional matrices.

  7. Hypoxia-induced secretion of TGF-β1 in mesenchymal stem cell promotes breast cancer cell progression.

    PubMed

    Hung, Shun-Pei; Yang, Muh-Hwa; Tseng, Kuo-Fung; Lee, Oscar K

    2013-01-01

    In solid tumors, a decreased oxygen and nutrient supply creates a hypoxic microenvironment in the central region. This hypoxic condition induces molecular responses of normal and cancer cells in the local area, including angiogenesis, metabolic changes, and metastasis. In addition, other cells including mesenchymal stem cells (MSCs) have been reported to be recruited into the hypoxic area of solid tumors. In our previous study, we found that hypoxic condition induces the secretion of growth factors and cytokines in MSCs, and here we demonstrate that elevated secretion of transforming growth factor-β1 (TGF-β1) by MSCs under hypoxia promotes the growth, motility, and invasive ability of breast cancer cells. It was found that TGF-β1 promoter activity was regulated by hypoxia, and the major hypoxia-regulated element was located between bp -1030 to -666 in front of the TGF-β1 promoter region. In ChIP assay, the results revealed that HIF-1 was bound to the hypoxia response element (HRE) of TGF-β1 promoter. Collectively, the results indicate that hypoxia microenvironment can enhance cancer cell growth through the paracrine effects of the MSCs by driving their TGF-β1 gene expression and secretion. Therefore, extra caution has to be exercised when considering hypoxia pretreatment of MSCs before cell transplantation into patients for therapeutic purposes, particularly in patients susceptible to tumor growth.

  8. Tumour MLH1 promoter region methylation testing is an effective pre-screen for Lynch Syndrome (HNPCC)

    PubMed Central

    Newton, K; Jorgensen, NM; Wallace, AJ; Buchanan, DD; Lalloo, F; McMahon, RFT; Hill, J; Evans, DG

    2016-01-01

    Background & Aims Lynch syndrome patients have DNA mismatch repair deficiency and up to 80% life-time risk of colorectal cancer. Screening of mutation carriers reduces colorectal cancer incidence and mortality. Selection for constitutional mutation testing relies on family history (Amsterdam and Bethesda Guidelines) and tumour derived biomarkers. Initial biomarker analysis uses mismatch repair protein immunohistochemistry and microsatellite instability. Abnormalities in either identify mismatch repair deficiency but do not differentiate sporadic epigenetic defects, due to MLH1 promoter region methylation (13% of CRCs) from Lynch Syndrome (4% of CRCs). A diagnostic biomarker capable of making this distinction would be valuable. This study compared two biomarkers in tumours with mismatch repair deficiency; quantification of methylation of the MLH1 promoter region using a novel assay and BRAF c.1799T>A, p.(Val600Glu) mutation status in the identification of constitutional mutations. Methods Tumour DNA was extracted (FFPE tissue) and pyrosequencing used to test for MLH1 promoter methylation and presence of the BRAF c.1799T>A, p.(Val600Glu) mutation 71 CRCs from individuals with pathogenic MLH1 mutations and 73 CRCs with sporadic MLH1 loss. Specificity and sensitivity was compared. Findings Unmethylated MLH1 promoter: sensitivity 94.4% (95% CI 86.2–98.4%), specificity 87.7% (95% CI 77.9–94.2%), Wild-type BRAF (codon 600): sensitivity 65.8% (95% CI 53.7–76.5%), specificity 98.6% (95% CI 92.4–100.0%) for the identification of those with pathogenic MLH1 mutations. Conclusions Quantitative MLH1 promoter region methylation using pyrosequencing is superior to BRAF codon 600 mutation status in identifying constitutional mutations in mismatch repair deficient tumours. PMID:25280751

  9. Analysis of Msx1 and Msx2 transactivation function in the context of the heat shock 70 (Hspa1b) gene promoter.

    PubMed

    Zhuang, Fengfeng; Nguyen, Manuel P; Shuler, Charles; Liu, Yi-Hsin

    2009-04-03

    Previous studies have shown that Msx proteins control gene transcription predominantly through repression mechanisms. However, gene expression studies using either the gain-of-function or the loss-of-function mutants revealed many gene targets whose expression require functional Msx proteins. To date, investigations into the mechanisms of Msx-dependent transactivation have been hindered by the lack of a responsive promoter. Here, we demonstrated the usefulness of the mouse Hspa1b promoter in probing Msx-dependent mechanisms of gene activation. We showed that Msx protein activates Hspa1b promoter via its C-terminal domain. The activation absolutely depends on the HSEs and physical interactions between Msx proteins and heat shock factors may play a contributing role.

  10. Ubiquitin carboxyl-terminal hydrolase 1 (UCHL1) is a potential tumour suppressor in prostate cancer and is frequently silenced by promoter methylation

    PubMed Central

    2011-01-01

    Background We have previously reported significant downregulation of ubiquitin carboxyl-terminal hydrolase 1 (UCHL1) in prostate cancer (PCa) compared to the surrounding benign tissue. UCHL1 plays an important role in ubiquitin system and different cellular processes such as cell proliferation and differentiation. We now show that the underlying mechanism of UCHL1 downregulation in PCa is linked to its promoter hypermethylation. Furthermore, we present evidences that UCHL1 expression can affect the behavior of prostate cancer cells in different ways. Results Methylation specific PCR analysis results showed a highly methylated promoter region for UCHL1 in 90% (18/20) of tumor tissue compared to 15% (3/20) of normal tissues from PCa patients. Pyrosequencing results confirmed a mean methylation of 41.4% in PCa whereas only 8.6% in normal tissues. To conduct functional analysis of UCHL1 in PCa, UCHL1 is overexpressed in LNCaP cells whose UCHL1 expression is normally suppressed by promoter methylation and found that UCHL1 has the ability to decrease the rate of cell proliferation and suppresses anchorage-independent growth of these cells. In further analysis, we found evidence that exogenous expression of UCHL1 suppress LNCaP cells growth probably via p53-mediated inhibition of Akt/PKB phosphorylation and also via accumulation of p27kip1 a cyclin dependant kinase inhibitor of cell cycle regulating proteins. Notably, we also observed that exogenous expression of UCHL1 induced a senescent phenotype that was detected by using the SA-ß-gal assay and might be due to increased p14ARF, p53, p27kip1 and decreased MDM2. Conclusion From these results, we propose that UCHL1 downregulation via promoter hypermethylation plays an important role in various molecular aspects of PCa biology, such as morphological diversification and regulation of proliferation. PMID:21999842

  11. Rev-erb beta regulates the Srebp-1c promoter and mRNA expression in skeletal muscle cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ramakrishnan, Sathiya N.; Lau, Patrick; Crowther, Lisa M.

    2009-10-30

    The nuclear hormone receptor, Rev-erb beta operates as a transcriptional silencer. We previously demonstrated that exogenous expression of Rev-erb{beta}{Delta}E in skeletal muscle cells increased Srebp-1c mRNA expression. We validated these in vitro observations by injection of an expression vector driving Rev-erb{beta}{Delta}E expression into mouse tibialis muscle that resulted in increased Srebp-1c mRNA expression. Paradoxically, Rev-erb{beta} siRNA expression in skeletal muscle cells repressed Srebp-1c expression, and indicated that Rev-erb{beta} expression was necessary for Srebp-1c expression. ChIP analysis demonstrated that Rev-erb{beta} was recruited to the Srebp-1c promoter. Moreover, Rev-erb{beta} trans-activated the Srebp-1c promoter, in contrast, Rev-erb{beta} efficiently repressed the Rev-erb{alpha} promoter, amore » previously characterized target gene. Finally, treatment with the Rev-erb agonist (hemin) (i) increased the trans-activation of the Srebp-1c promoter by Rev-erb{beta}; and (ii) increased Rev-erb{beta} and Srebp-1c mRNA expression. These data suggest that Rev-erb{beta} has the potential to activate gene expression, and is a positive regulator of Srebp-1c, a regulator of lipogenesis.« less

  12. Influence of dioxygen on the promotional effect of Bi during Pt-catalyzed oxidation of 1,6-hexanediol

    DOE PAGES

    Xie, Jiahan; Huang, Benjamin; Yin, Kehua; ...

    2016-05-24

    In this study, a series of carbon-supported, Bi-promoted Pt catalysts with various Bi/Pt atomic ratios was prepared by selectively depositing Bi on Pt nanoparticles. The catalysts were evaluated for 1,6-hexanediol oxidation activity in aqueous solvent under different dioxygen pressures. The rate of diol oxidation on the basis of Pt loading over a Bi-promoted catalyst was 3 times faster than that of an unpromoted Pt catalyst under 0.02 MPa of O 2, whereas the unpromoted catalyst was more active than the promoted catalyst under 1 MPa of O 2. After liquid-phase catalyst pretreatment and 1,6-hexanediol oxidation, migration of Bi on themore » carbon support was observed. The reaction order in O 2 was 0 over Bi-promoted Pt/C in comparison to 0.75 over unpromoted Pt/C in the range of 0.02–0.2 MPa of O 2. Under low O 2 pressure, rate measurements in D 2O instead of H 2O solvent revealed a moderate kinetic isotope effect (rate H2O/rate D2O) on 1,6-hexanediol oxidation over Pt/C (KIE = 1.4), whereas a negligible effect was observed on Bi-Pt/C (KIE = 0.9), indicating that the promotional effect of Bi could be related to the formation of surface hydroxyl groups from the reaction of dioxygen and water. No significant change in product distribution or catalyst stability was observed with Bi promotion, regardless of the dioxygen pressure.« less

  13. FGF1 and IGF1-conditioned 3D culture system promoted the amplification and cancer stemness of lung cancer cells.

    PubMed

    Liu, Pengpeng; Zhang, Rui; Yu, Wenwen; Ye, Yingnan; Cheng, Yanan; Han, Lei; Dong, Li; Chen, Yongzi; Wei, Xiyin; Yu, Jinpu

    2017-12-01

    Lung cancer stem cells (LCSCs) are considered as the cellular origins of metastasis and relapse of lung cancer. However, routine two-dimensional culture system (2D-culture) hardly mimics the growth and functions of LCSCs in vivo and therefore significantly decreases the stemness activity of LCSCs. In this study, we constructed a special BME-based three-dimensional culture system (3D-culture) to amplify LCSCs in human lung adenocarcinoma cell line A549 cells and found 3D-culture promoted the enrichment and amplification of LCSCs in A549 cells displaying higher proliferation potential and invasion activity, but lower apoptosis. The expression and secretion levels of FGF1 and IGF1 were dramatically elevated in 3D-culture compared to 2D-culture. After growing in FGF1 and IGF1-conditioned 3D-culture, the proportion of LCSCs with specific stemness phenotypes in A549 cells significantly increased compared to that in conventional 3D suspension culture system. Further results indicated that FGF1 and IGF1 promoted the amplification and cancer stemness of LCSCs dependent on MAPK signaling pathway. Our data firstly established a growth factors-conditioned 3D-culture for LCSCs and demonstrated the effects of FGF1 and IGF1 in promoting the enrichment and amplification of LCSCs which might provide a feasible cell model in vitro for both mechanism study and translational research on lung cancer. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Reactive glia promote development of CD103+ CD69+ CD8+ T-cells through programmed cell death-ligand 1 (PD-L1).

    PubMed

    Prasad, Sujata; Hu, Shuxian; Sheng, Wen S; Chauhan, Priyanka; Lokensgard, James R

    2018-06-01

    Previous work from our laboratory has demonstrated in vivo persistence of CD103 + CD69 + brain resident memory CD8 + T-cells (bT RM ) following viral infection, and that the PD-1: PD-L1 pathway promotes development of these T RM cells within the brain. Although glial cells express low basal levels of PD-L1, its expression is upregulated upon IFN-γ-treatment, and they have been shown to modulate antiviral T-cell effector responses through the PD-1: PD-L1 pathway. We performed flow cytometric analysis of cells from co-cultures of mixed glia and CD8 + T-cells obtained from wild type mice to investigate the role of glial cells in the development of bT RM . In this study, we show that interactions between reactive glia and anti-CD3 Ab-stimulated CD8 + T-cells promote development of CD103 + CD69 + CD8 + T-cells through engagement of the PD-1: PD-L1 pathway. These studies used co-cultures of primary murine glial cells obtained from WT animals along with CD8 + T-cells obtained from either WT or PD-1 KO mice. We found that αCD3 Ab-stimulated CD8 + T-cells from WT animals increased expression of CD103 and CD69 when co-cultured with primary murine glial cells. In contrast, significantly reduced expression of CD103 and CD69 was observed using CD8 + T-cells from PD-1 KO mice. We also observed that reactive glia promoted high levels of CD127, a marker of memory precursor effector cells (MPEC), on CD69 + CD8 + T-cells, which promotes development of T RM cells. Interestingly, results obtained using T-cells from PD-1 KO animals showed significantly reduced expression of CD127 on CD69 + CD8 + cells. Additionally, blocking of glial PD-L1 resulted in decreased expression of CD103, along with reduced CD127 on CD69 + CD8 + T-cells. Taken together, these results demonstrate a role for activated glia in promoting development of bT RM through the PD-1: PD-L1 pathway. © 2018 The Authors. Immunity, Inflammation and Disease Published by John Wiley & Sons Ltd.

  15. Lynch syndrome associated with two MLH1 promoter variants and allelic imbalance of MLH1 expression.

    PubMed

    Hesson, Luke B; Packham, Deborah; Kwok, Chau-To; Nunez, Andrea C; Ng, Benedict; Schmidt, Christa; Fields, Michael; Wong, Jason W H; Sloane, Mathew A; Ward, Robyn L

    2015-06-01

    Lynch syndrome is a hereditary cancer syndrome caused by a constitutional mutation in one of the mismatch repair genes. The implementation of predictive testing and targeted preventative surveillance is hindered by the frequent finding of sequence variants of uncertain significance in these genes. We aimed to determine the pathogenicity of previously reported variants (c.-28A>G and c.-7C>T) within the MLH1 5'untranslated region (UTR) in two individuals from unrelated suspected Lynch syndrome families. We investigated whether these variants were associated with other pathogenic alterations using targeted high-throughput sequencing of the MLH1 locus. We also determined their relationship to gene expression and epigenetic alterations at the promoter. Sequencing revealed that the c.-28A>G and c.-7C>T variants were the only potentially pathogenic alterations within the MLH1 gene. In both individuals, the levels of transcription from the variant allele were reduced to 50% compared with the wild-type allele. Partial loss of expression occurred in the absence of constitutional epigenetic alterations within the MLH1 promoter. We propose that these variants may be pathogenic due to constitutional partial loss of MLH1 expression, and that this may be associated with intermediate penetrance of a Lynch syndrome phenotype. Our findings provide further evidence of the potential importance of noncoding variants in the MLH1 5'UTR in the pathogenesis of Lynch syndrome. © 2015 The Authors. **Human Mutation published by Wiley Periodicals, Inc.

  16. Lynch Syndrome Associated with Two MLH1 Promoter Variants and Allelic Imbalance of MLH1 Expression

    PubMed Central

    Hesson, Luke B; Packham, Deborah; Kwok, Chau-To; Nunez, Andrea C; Ng, Benedict; Schmidt, Christa; Fields, Michael; Wong, Jason WH; Sloane, Mathew A; Ward, Robyn L

    2015-01-01

    Lynch syndrome is a hereditary cancer syndrome caused by a constitutional mutation in one of the mismatch repair genes. The implementation of predictive testing and targeted preventative surveillance is hindered by the frequent finding of sequence variants of uncertain significance in these genes. We aimed to determine the pathogenicity of previously reported variants (c.-28A>G and c.-7C>T) within the MLH1 5′untranslated region (UTR) in two individuals from unrelated suspected Lynch syndrome families. We investigated whether these variants were associated with other pathogenic alterations using targeted high-throughput sequencing of the MLH1 locus. We also determined their relationship to gene expression and epigenetic alterations at the promoter. Sequencing revealed that the c.-28A>G and c.-7C>T variants were the only potentially pathogenic alterations within the MLH1 gene. In both individuals, the levels of transcription from the variant allele were reduced to 50% compared with the wild-type allele. Partial loss of expression occurred in the absence of constitutional epigenetic alterations within the MLH1 promoter. We propose that these variants may be pathogenic due to constitutional partial loss of MLH1 expression, and that this may be associated with intermediate penetrance of a Lynch syndrome phenotype. Our findings provide further evidence of the potential importance of noncoding variants in the MLH1 5′UTR in the pathogenesis of Lynch syndrome. PMID:25762362

  17. An APOA1 promoter polymorphism is associated with cognitive performance in patients with multiple sclerosis.

    PubMed

    Koutsis, G; Panas, M; Giogkaraki, E; Karadima, G; Sfagos, C; Vassilopoulos, D

    2009-02-01

    Elevated ApoA1 levels have been associated with decreased dementia risk. The A-allele of the APOA1 -75G/A promoter polymorphism has been associated with elevated ApoA1 levels. We sought to investigate the effect of the APOA1 -75G/A promoter polymorphism on cognitive performance in patients with multiple sclerosis (MS). A total of 138 patients with MS and 43 controls were studied and underwent neuropsychological assessment with Rao's Brief Repeatable Battery and the Stroop test. All patients were genotyped for APOA1. APOA1 A-allele carriers displayed superior overall cognitive performance compared with non-carriers (P 0.008) and had a three-fold decrease in the relative risk of overall cognitive impairment (OR 0.29, 95% CI 0.11-0.74). Regarding performance on individual cognitive domains, although APOA1 A-allele carriers performed better than non-carriers on all tests, this was significant only for semantic verbal fluency and the Stroop interference task (P 0.036 and 0.018, respectively). We found an association of the APOA1 -75G/A promoter polymorphism with cognitive performance in MS. This effect was most prominent on semantic verbal fluency and the Stroop interference task.

  18. Single-Nucleotide-Specific Targeting of the Tf1 Retrotransposon Promoted by the DNA-Binding Protein Sap1 of Schizosaccharomyces pombe.

    PubMed

    Hickey, Anthony; Esnault, Caroline; Majumdar, Anasuya; Chatterjee, Atreyi Ghatak; Iben, James R; McQueen, Philip G; Yang, Andrew X; Mizuguchi, Takeshi; Grewal, Shiv I S; Levin, Henry L

    2015-11-01

    Transposable elements (TEs) constitute a substantial fraction of the eukaryotic genome and, as a result, have a complex relationship with their host that is both adversarial and dependent. To minimize damage to cellular genes, TEs possess mechanisms that target integration to sequences of low importance. However, the retrotransposon Tf1 of Schizosaccharomyces pombe integrates with a surprising bias for promoter sequences of stress-response genes. The clustering of integration in specific promoters suggests that Tf1 possesses a targeting mechanism that is important for evolutionary adaptation to changes in environment. We report here that Sap1, an essential DNA-binding protein, plays an important role in Tf1 integration. A mutation in Sap1 resulted in a 10-fold drop in Tf1 transposition, and measures of transposon intermediates support the argument that the defect occurred in the process of integration. Published ChIP-Seq data on Sap1 binding combined with high-density maps of Tf1 integration that measure independent insertions at single-nucleotide positions show that 73.4% of all integration occurs at genomic sequences bound by Sap1. This represents high selectivity because Sap1 binds just 6.8% of the genome. A genome-wide analysis of promoter sequences revealed that Sap1 binding and amounts of integration correlate strongly. More important, an alignment of the DNA-binding motif of Sap1 revealed integration clustered on both sides of the motif and showed high levels specifically at positions +19 and -9. These data indicate that Sap1 contributes to the efficiency and position of Tf1 integration. Copyright © 2015 by the Genetics Society of America.

  19. Single-Nucleotide-Specific Targeting of the Tf1 Retrotransposon Promoted by the DNA-Binding Protein Sap1 of Schizosaccharomyces pombe

    PubMed Central

    Hickey, Anthony; Esnault, Caroline; Majumdar, Anasuya; Chatterjee, Atreyi Ghatak; Iben, James R.; McQueen, Philip G.; Yang, Andrew X.; Mizuguchi, Takeshi; Grewal, Shiv I. S.; Levin, Henry L.

    2015-01-01

    Transposable elements (TEs) constitute a substantial fraction of the eukaryotic genome and, as a result, have a complex relationship with their host that is both adversarial and dependent. To minimize damage to cellular genes, TEs possess mechanisms that target integration to sequences of low importance. However, the retrotransposon Tf1 of Schizosaccharomyces pombe integrates with a surprising bias for promoter sequences of stress-response genes. The clustering of integration in specific promoters suggests that Tf1 possesses a targeting mechanism that is important for evolutionary adaptation to changes in environment. We report here that Sap1, an essential DNA-binding protein, plays an important role in Tf1 integration. A mutation in Sap1 resulted in a 10-fold drop in Tf1 transposition, and measures of transposon intermediates support the argument that the defect occurred in the process of integration. Published ChIP-Seq data on Sap1 binding combined with high-density maps of Tf1 integration that measure independent insertions at single-nucleotide positions show that 73.4% of all integration occurs at genomic sequences bound by Sap1. This represents high selectivity because Sap1 binds just 6.8% of the genome. A genome-wide analysis of promoter sequences revealed that Sap1 binding and amounts of integration correlate strongly. More important, an alignment of the DNA-binding motif of Sap1 revealed integration clustered on both sides of the motif and showed high levels specifically at positions +19 and −9. These data indicate that Sap1 contributes to the efficiency and position of Tf1 integration. PMID:26358720

  20. COMP-1 promotes competitive advantage of nematode sperm

    PubMed Central

    Hansen, Jody M; Chavez, Daniela R; Stanfield, Gillian M

    2015-01-01

    Competition among sperm to fertilize oocytes is a ubiquitous feature of sexual reproduction as well as a profoundly important aspect of sexual selection. However, little is known about the cellular mechanisms sperm use to gain competitive advantage or how these mechanisms are regulated genetically. In this study, we utilize a forward genetic screen in Caenorhabditis elegans to identify a gene, comp-1, whose function is specifically required in competitive contexts. We show that comp-1 functions in sperm to modulate their migration through and localization within the reproductive tract, thereby promoting their access to oocytes. Contrary to previously described models, comp-1 mutant sperm show no defects in size or velocity, thereby defining a novel pathway for preferential usage. Our results indicate not only that sperm functional traits can influence the outcome of sperm competition, but also that these traits can be modulated in a context-dependent manner depending on the presence of competing sperm. DOI: http://dx.doi.org/10.7554/eLife.05423.001 PMID:25789512

  1. Heme Oxygenase-1 Promotes Delayed Wound Healing in Diabetic Rats

    PubMed Central

    Chen, Qing-Ying; Wang, Guo-Guang; Li, Wei; Jiang, Yu-Xin; Lu, Xiao-Hua; Zhou, Ping-Ping

    2016-01-01

    Diabetic ulcers are one of the most serious and costly chronic complications for diabetic patients. Hyperglycemia-induced oxidative stress may play an important role in diabetes and its complications. The aim of the study was to explore the effect of heme oxygenase-1 on wound closure in diabetic rats. Diabetic wound model was prepared by making an incision with full thickness in STZ-induced diabetic rats. Wounds from diabetic rats were treated with 10% hemin ointment for 21 days. Increase of HO-1 protein expression enhanced anti-inflammation and antioxidant in diabetic rats. Furthermore, HO-1 increased the levels of VEGF and ICAM-1 and expressions of CBS and CSE protein. In summary, HO-1 promoted the wound closure by augmenting anti-inflammation, antioxidant, and angiogenesis in diabetic rats. PMID:26798657

  2. A functional study of proximal goat β-casein promoter and intron 1 in immortalized goat mammary epithelial cells.

    PubMed

    Kung, M H; Lee, Y J; Hsu, J T; Huang, M C; Ju, Y T

    2015-06-01

    Goat β-casein (CSN2) promoter has been extensively used to derive expression of recombinant therapeutic protein in transgenic goats; however, little direct evidence exists for signaling molecules and the cis-elements of goat CSN2 promoter in response to lactogenic hormone stimulation in goat mammary epithelial cells. Here, we use an immortalized caprine mammary epithelial cell line (CMC) to search for evidence of the above. Serial 5'-flanking regions deleted of promoter and intron 1 in goat CSN2 (-4,047 to +2,054) driven by firefly luciferase reporter gene were constructed and applied to measure promoter activity in CMC. The intron 1 region (+393 to +501) significantly decreased basal activity of the promoter. This finding contradicts other studies of the role of intron 1. The signal transducer and activator of transcription (STAT)5a played a significant role in activating promoter activity by prolactin stimulation. Hydrocortisone enhanced and prolonged the activity of STAT5a and promoter in CMC, but was independent of the glucocorticoid receptor response element. The minimum length of the CSN2 promoter segment in response to lactogenic stimulation was confirmed by 5' serial deletions. A cis-element located from -300 to -90 in proximal goat CSN2 promoter that is absent in bovine and human CSN2 promoter was newly identified. We demonstrated the presence of a STAT5a binding site (-102 to -82) and preservation of the guanosine nucleotide at position -90 based on responses to the presence of lactogenic hormone using internal deletions and point mutations of the predicted STAT5a binding site, and chromatin immunoprecipitation assay. Together, these findings demonstrate that the proximal -300 bp of goat CSN2 promoter containing the STAT5a binding site (-102 to -82) is the response element for lactogenic hormone stimulation. Additionally, intron 1 may be required for tissue or developmental stage-specific expression in mammary gland. The role of the far-distal regions of

  3. Draft Genome Sequences of Three Novel Low-Abundance Species Strains Isolated from Kefir Grain.

    PubMed

    Kim, Yongkyu; Blasche, Sonja; Patil, Kiran R

    2017-09-28

    We report here the genome sequences of three novel bacterial species strains- Bacillus kefirresidentii Opo, Rothia kefirresidentii KRP, and Streptococcus kefirresidentii YK-isolated from kefir grains collected in Germany. The draft genomes of these isolates were remarkably dissimilar (average nucleotide identities, 77.80%, 89.01%, and 92.10%, respectively) to those of the previously sequenced strains. Copyright © 2017 Kim et al.

  4. Elucidating the functional role of endoreduplication in tomato fruit development

    PubMed Central

    Chevalier, Christian; Nafati, Mehdi; Mathieu-Rivet, Elodie; Bourdon, Matthieu; Frangne, Nathalie; Cheniclet, Catherine; Renaudin, Jean-Pierre; Gévaudant, Frédéric; Hernould, Michel

    2011-01-01

    Background Endoreduplication is the major source of endopolyploidy in higher plants. The process of endoreduplication results from the ability of cells to modify their classical cell cycle into a partial cell cycle where DNA synthesis occurs independently from mitosis. Despite the ubiquitous occurrence of the phenomenon in eukaryotic cells, the physiological meaning of endoreduplication remains vague,although several roles during plant development have been proposed, mostly related to cell differentiation and cell size determination. Scope Here recent advances in the knowledge of endoreduplication and fruit organogenesis are reviewed, focusing on tomato (Solanum lycopersicum) as a model, and the functional analyses of endoreduplication-associated regulatory genes in tomato fruit are described. Conclusions The cyclin-dependent kinase inhibitory kinase WEE1 and the anaphase promoting complex activator CCS52A both participate in the control of cell size and the endoreduplication process driving cell expansion during early fruit development in tomato. Moreover the fruit-specific functional analysis of the tomato CDK inhibitor KRP1 reveals that cell size and fruit size determination can be uncoupled from DNA ploidy levels, indicating that endoreduplication acts rather as a limiting factor for cell growth. The overall functional data contribute to unravelling the physiological role of endoreduplication in growth induction of fleshy fruits. PMID:21199834

  5. FERMT1 promoter mutations in patients with Kindler syndrome.

    PubMed

    Has, C; Chmel, N; Levati, L; Neri, I; Sonnenwald, T; Pigors, M; Godbole, K; Dudhbhate, A; Bruckner-Tuderman, L; Zambruno, G; Castiglia, D

    2015-09-01

    Mutations in the FERMT1 gene, encoding the focal adhesion protein kindlin-1 underlie the Kindler syndrome (KS), an autosomal recessive skin disorder with a phenotype comprising skin blistering, photosensitivity, progressive poikiloderma with extensive skin atrophy, and propensity to skin cancer. The FERMT1 mutational spectrum comprises gross genomic deletions, splice site, nonsense, and frameshift mutations, which are scattered over the coding region spanning exon 2-15. We now report three KS families with mutations affecting the promoter region of FERMT1. Two of these mutations are large deletions (∼38.0 and 1.9 kb in size) and one is a single nucleotide variant (c.-20A>G) within the 5' untranslated region (UTR). Each mutation resulted in loss of gene expression in patient skin or cultured keratinocytes. Reporter assays showed the functional relevance of the genomic regions deleted in our patients for FERMT1 gene transcription and proved the causal role of the c.-20A>G variant in reducing transcriptional activity. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Anyalysis of Msx1 and Msx2 Transactivation Function in the Context of the Heat Shock 70 (Hspa1b) Gene Promoter

    PubMed Central

    Zhuang, Fengfeng; Nguyen, Manuel P.; Shuler, Charles; Liu, Yi-Hsin

    2009-01-01

    Previous studies have shown that Msx proteins control gene transcription predominantly through repression mechanisms. However, gene expression studies using either the gain-of-function or the loss-of-function mutants revealed many gene targets whose expression require functional Msx proteins. To date, investigations into the mechanisms of Msx-dependent trans-activation have been hindered by the lack of a responsive promoter. Here, we demonstrated the usefulness of the mouse Hspa1b promoter in probing Msx-dependent mechanisms of gene activation. We showed that Msx protein activates Hspa1b promoter via its C-terminal domain. The activation absolutely depends on the HSEs and physical interactions between Msx proteins and Heat shock factors may play a contributing role. PMID:19338779

  7. Effect of folate deficiency on promoter methylation and gene expression of Esr1, Cav1, and Elavl1, and its influence on spermatogenesis.

    PubMed

    Yuan, Hong-Fang; Zhao, Kai; Zang, Yu; Liu, Chun-Yan; Hu, Zhi-Yong; Wei, Jia-Jing; Zhou, Ting; Li, Ying; Zhang, Hui-Ping

    2017-04-11

    This study aims to investigate the effect of folate deficiency on the male reproductive function and the underlying mechanism. A total of 269 screened participants from 421 recruitments were enrolled in this study. An animal model of folate deficiency was constructed. Folate concentration was measured in the ejaculate, and its association with semen parameters was then determined. The expression and promoter methylation status of ESR1, CAV1, and ELAVL1 were also evaluated. Results showed that seminal plasma folate level was significantly lower among subjects with azoospermia than those with normozoospermia. Low folate level was significantly correlated with low sperm concentration in men with normozoospermia. Folate deficiency significantly reduced the expression of ESR1, CAV1, and ELAVL1, which are critical to spermatogenesis. However, low folate levels did not increase the methylation levels of the promoter regions of ESR1, CAV1, and ELAVL1 in human sperm DNA. Thus, folate deficiency impairs spermatogenesis may partly due to inhibiting the expression of these genes. Thus future research should determine the significance of sufficient folate status in male fertilization and subsequent pregnancy outcomes.

  8. Id-1 promotes osteosarcoma cell growth and inhibits cell apoptosis via PI3K/AKT signaling pathway

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hao, Liang; Liao, Qi; Tang, Qiang

    2016-02-12

    Accumulating evidence reveals that Id-1 is upregulated and functions as a potential tumor promoter in several human cancer types. However, the role of Id-1 in osteosarcoma (OS) is unknown. In present study, we found that Id-1 expression was elevated in OS tissues than adjacent normal bone tissues. More importantly, we demonstrated that overexpression of Id-1 is significantly correlated with tumor progression and poor survival in OS patients. Furthermore, increased expression of Id-1 was observed in OS cell lines and ectopic expression of Id-1 significantly enhanced in vitro cell proliferation and promoted in vivo tumor growth, whereas knockdown of Id-1 suppressed OS cellsmore » growth. Moreover, our experimental data revealed that Id-1 promotes cell proliferation by facilitating cell cycle progression and inhibits cell apoptosis. Mechanistically, the effects of Id-1 in OS cells is at least partly through activation of PI3K/Akt signaling pathway. Therefore, we identified a tumorigenic role of Id-1 in OS and suggested a potential therapeutic target for OS patients. - Highlights: • Id-1 expression is positively correlated in OS patients with poor prognosis. • Overexpression of Id-1 promotes OS cell growth in vitro and in vivo. • Id-1induces cell cycle progression and inhibits cell apoptosis. • PI3K/Akt signaling pathway contributed to the oncogenic effects of Id-1 in OS cells.« less

  9. Epigenetic silencing of RASSF1A deregulates cytoskeleton and promotes malignant behavior of adrenocortical carcinoma

    PubMed Central

    2013-01-01

    Background Adrenocortical carcinoma (ACC) is a rare endocrine malignancy with high mutational heterogeneity and a generally poor clinical outcome. Despite implicated roles of deregulated TP53, IGF-2 and Wnt signaling pathways, a clear genetic association or unique mutational link to the disease is still missing. Recent studies suggest a crucial role for epigenetic modifications in the genesis and/or progression of ACC. This study specifically evaluates the potential role of epigenetic silencing of RASSF1A, the most commonly silenced tumor suppressor gene, in adrenocortical malignancy. Results Using adrenocortical tumor and normal tissue specimens, we show a significant reduction in expression of RASSF1A mRNA and protein in ACC. Methylation-sensitive and -dependent restriction enzyme based PCR assays revealed significant DNA hypermethylation of the RASSF1A promoter, suggesting an epigenetic mechanism for RASSF1A silencing in ACC. Conversely, the RASSF1A promoter methylation profile in benign adrenocortical adenomas (ACAs) was found to be very similar to that found in normal adrenal cortex. Enforced expression of ectopic RASSF1A in the SW-13 ACC cell line reduced the overall malignant behavior of the cells, which included impairment of invasion through the basement membrane, cell motility, and solitary cell survival and growth. On the other hand, expression of RASSF1A/A133S, a loss-of-function mutant form of RASSF1A, failed to elicit similar malignancy-suppressing responses in ACC cells. Moreover, association of RASSF1A with the cytoskeleton in RASSF1A-expressing ACC cells and normal adrenal cortex suggests a role for RASSF1A in modulating microtubule dynamics in the adrenal cortex, and thereby potentially blocking malignant progression. Conclusions Downregulation of RASSF1A via promoter hypermethylation may play a role in the malignant progression of adrenocortical carcinoma possibly by abrogating differentiation-promoting RASSF1A- microtubule interactions. PMID

  10. FOXA1 promotes tumor cell proliferation through AR involving the Notch pathway in endometrial cancer

    PubMed Central

    2014-01-01

    Background Increasing evidence suggests that forkhead box A1 (FOXA1) is frequently dysregulated in many types of human cancers. However, the exact function and mechanism of FOXA1 in human endometrial cancer (EC) remains unclear. Methods FOXA1 expression, androgen receptor (AR) expression, and the relationships of these two markers with clinicopathological factors were determined by immunohistochemistry analysis. FOXA1 and AR were up-regulated by transient transfection with plasmids, and were down-regulated by transfection with siRNA or short hairpin RNA (shRNA). The effects of FOXA1 depletion and FOXA1 overexpression on AR-mediated transcription as well as Notch pathway and their impact on EC cell proliferation were examined by qRT-PCR, western blotting, co-immunoprecipitation, ChIP-PCR, MTT, colony-formation, and xenograft tumor–formation assays. Results We found that the expression of FOXA1 and AR in ECs was significantly higher than that in a typical hyperplasia and normal tissues. FOXA1 expression was significantly correlated with AR expression in clinical tissues. High FOXA1 levels positively correlated with pathological grade and depth of myometrial invasion in EC. High AR levels also positively correlated with pathological grade in EC. Moreover, the expression of XBP1, MYC, ZBTB16, and UHRF1, which are downstream targets of AR, was promoted by FOXA1 up-regulation or inhibited by FOXA1 down-regulation. Co-immunoprecipitation showed that FOXA1 interacted with AR in EC cells. ChIP-PCR assays showed that FOXA1 and AR could directly bind to the promoter and enhancer regions upstream of MYC. Mechanistic investigation revealed that over-expression of Notch1 and Hes1 proteins by FOXA1 could be reversed by AR depletion. In addition, we showed that down-regulation of AR attenuated FOXA1-up-regulated cell proliferation. However, AR didn’t influence the promotion effect of FOXA1 on cell migration and invasion. In vivo xenograft model, FOXA1 knockdown reduced the

  11. Tyrosine Phosphorylation of the Pioneer Transcription Factor FoxA1 Promotes Activation of Estrogen Signaling.

    PubMed

    Yamaguchi, Noritaka; Shibazaki, Misato; Yamada, Chiaki; Anzai, Erina; Morii, Mariko; Nakayama, Yuji; Kuga, Takahisa; Hashimoto, Yuuki; Tomonaga, Takeshi; Yamaguchi, Naoto

    2017-06-01

    The pioneer transcription factor FoxA1 plays an important role in estrogen signaling by opening closed chromatin and promoting recruitment of the estrogen receptor to its target regions in DNA. In this study, we analyzed tyrosine phosphorylation of FoxA1 by the non-receptor-type tyrosine kinase c-Abl. c-Abl was shown to phosphorylate FoxA1 at multiple sites, especially in the N- and C-terminal regions. Tyr429 and Tyr464 were identified as the major phosphorylation sites in the FoxA1 C-terminal region. The phosphomimetic and nonphosphorylatable FoxA1 mutants were generated by glutamic acid and phenylalanine substitutions at these tyrosine residues, respectively. The phosphomimetic FoxA1 promoted the activation of estrogen signaling, whereas the nonphosphorylatable FoxA1 suppressed its activation. Stimulation with the epidermal growth factor, which activates c-Abl, enhanced the activation of estrogen signaling. In contrast, the c-Abl inhibitor imatinib reduced its activation. The phosphomimetic FoxA1 mutant showed a higher affinity toward histone H3 than the wild-type. These results suggest that c-Abl-mediated phosphorylation of FoxA1 promotes the activation of estrogen signaling by inducing its binding to histones. J. Cell. Biochem. 118: 1453-1461, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  12. Sema-1a Reverse Signaling Promotes Midline Crossing in Response to Secreted Semaphorins.

    PubMed

    Hernandez-Fleming, Melissa; Rohrbach, Ethan W; Bashaw, Greg J

    2017-01-03

    Commissural axons must cross the midline to form functional midline circuits. In the invertebrate nerve cord and vertebrate spinal cord, midline crossing is mediated in part by Netrin-dependent chemoattraction. Loss of crossing, however, is incomplete in mutants for Netrin or its receptor Frazzled/DCC, suggesting the existence of additional pathways. We identified the transmembrane Semaphorin, Sema-1a, as an important regulator of midline crossing in the Drosophila CNS. We show that in response to the secreted Semaphorins Sema-2a and Sema-2b, Sema-1a functions as a receptor to promote crossing independently of Netrin. In contrast to other examples of reverse signaling where Sema1a triggers repulsion through activation of Rho in response to Plexin binding, in commissural neurons Sema-1a acts independently of Plexins to inhibit Rho to promote attraction to the midline. These findings suggest that Sema-1a reverse signaling can elicit distinct axonal responses depending on differential engagement of distinct ligands and signaling effectors. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  13. Differential vitamin D 24-hydroxylase/CYP24A1 gene promoter methylation in endothelium from benign and malignant human prostate

    PubMed Central

    Karpf, Adam R; Omilian, Angela R; Bshara, Wiam; Tian, Lili; Tangrea, Michael A; Morrison, Carl D; Johnson, Candace S

    2011-01-01

    Epigenetic alterations occur in tumor-associated vessels in the tumor microenvironment. Methylation of the CYP24A1 gene promoter differs in endothelial cells isolated from tumors and non-tumor microenvironments in mice. The epigenetic makeup of endothelial cells of human tumor-associated vasculature is unknown due to difficulty of isolating endothelial cells populations from a heterogeneous tissue microenvironment. To ascertain CYP24A1 promoter methylation in tumor-associated endothelium, we utilized laser microdissection guided by CD31 immunohistochemistry to procure endothelial cells from human prostate tumor specimens. Prostate tissues were obtained following robotic radical prostatectomy from men with clinically localized prostate cancer. Adjacent histologically benign prostate tissues were used to compare endothelium from benign versus tumor microenvironments. Sodium bisulfite sequencing of CYP24A1 promoter region showed that the average CYP24A1 promoter methylation in the endothelium was 20% from the tumor microenvironment compared with 8.2% in the benign microenvironment (p < 0.05). A 2-fold to 17-fold increase in CYP24A1 promoter methylation was observed in the prostate tumor endothelium compared with the matched benign prostate endothelium in four patient samples, while CYP24A1 promoter methylation remained unchanged in two patient samples. In addition, there is no correlation of the level of CYP24A1 promoter methylation in prostate tumor-associated endothelium with that of epithelium/stroma. This study demonstrates that the CYP24A1 promoter is methylated in tumor-associated endothelium, indicating that epigenetic alterations in CYP24A1 may play a role in determining the phenotype of tumor-associated vasculature in the prostate tumor microenvironment. PMID:21725204

  14. Tissue Inhibitor of Matrix Metalloproteinase-1 Promotes Myocardial Fibrosis by Mediating CD63-Integrin β1 Interaction.

    PubMed

    Takawale, Abhijit; Zhang, Pu; Patel, Vaibhav B; Wang, Xiuhua; Oudit, Gavin; Kassiri, Zamaneh

    2017-06-01

    Myocardial fibrosis is excess accumulation of the extracellular matrix fibrillar collagens. Fibrosis is a key feature of various cardiomyopathies and compromises cardiac systolic and diastolic performance. TIMP1 (tissue inhibitor of metalloproteinase-1) is consistently upregulated in myocardial fibrosis and is used as a marker of fibrosis. However, it remains to be determined whether TIMP1 promotes tissue fibrosis by inhibiting extracellular matrix degradation by matrix metalloproteinases or via an matrix metalloproteinase-independent pathway. We examined the function of TIMP1 in myocardial fibrosis using Timp1 -deficient mice and 2 in vivo models of myocardial fibrosis (angiotensin II infusion and cardiac pressure overload), in vitro analysis of adult cardiac fibroblasts, and fibrotic myocardium from patients with dilated cardiomyopathy (DCM). Timp1 deficiency significantly reduced myocardial fibrosis in both in vivo models of cardiomyopathy. We identified a novel mechanism for TIMP1 action whereby, independent from its matrix metalloproteinase-inhibitory function, it mediates an association between CD63 (cell surface receptor for TIMP1) and integrin β1 on cardiac fibroblasts, initiates activation and nuclear translocation of Smad2/3 and β-catenin, leading to de novo collagen synthesis. This mechanism was consistently observed in vivo, in cultured cardiac fibroblasts, and in human fibrotic myocardium. In addition, after long-term pressure overload, Timp1 deficiency persistently reduced myocardial fibrosis and ameliorated diastolic dysfunction. This study defines a novel matrix metalloproteinase-independent function of TIMP1 in promoting myocardial fibrosis. As such targeting TIMP1 could prove to be a valuable approach in developing antifibrosis therapies. © 2017 American Heart Association, Inc.

  15. Physiological cyclic strain promotes endothelial cell survival via the induction of heme oxygenase-1

    PubMed Central

    Liu, Xiao-ming; Peyton, Kelly J.

    2013-01-01

    Endothelial cells (ECs) are constantly subjected to cyclic strain that arises from periodic change in vessel wall diameter as a result of pulsatile blood flow. Application of physiological levels of cyclic strain inhibits EC apoptosis; however, the underlying mechanism is not known. Since heme oxygenase-1 (HO-1) is a potent inhibitor of apoptosis, the present study investigated whether HO-1 contributes to the antiapoptotic action of cyclic strain. Administration of physiological cyclic strain (6% at 1 Hz) to human aortic ECs stimulated an increase in HO-1 activity, protein, and mRNA expression. The induction of HO-1 was preceded by a rise in reactive oxygen species (ROS) and Nrf2 protein expression. Cyclic strain also stimulated an increase in HO-1 promoter activity that was prevented by mutating the antioxidant responsive element in the promoter or by overexpressing dominant-negative Nrf2. In addition, the strain-mediated induction of HO-1 and activation of Nrf2 was abolished by the antioxidant N-acetyl-l-cysteine. Finally, application of cyclic strain blocked inflammatory cytokine-mediated EC death and apoptosis. However, the protective action of cyclic strain was reversed by the HO inhibitor tin protoporphyrin-IX and was absent in ECs isolated from HO-1-deficient mice. In conclusion, the present study demonstrates that a hemodynamically relevant level of cyclic strain stimulates HO-1 gene expression in ECs via the ROS-Nrf2 signaling pathway to inhibit EC death. The ability of cyclic strain to induce HO-1 expression may provide an important mechanism by which hemodynamic forces promote EC survival and vascular homeostasis. PMID:23604711

  16. The HIP1 binding site is required for growth regulation of the dihydrofolate reductase gene promoter.

    PubMed

    Means, A L; Slansky, J E; McMahon, S L; Knuth, M W; Farnham, P J

    1992-03-01

    The transcription rate of the dihydrofolate reductase (DHFR) gene increases at the G1/S boundary of the proliferative cell cycle. Through analysis of transiently and stably transfected NIH 3T3 cells, we have now demonstrated that DHFR promoter sequences extending from -270 to +20 are sufficient to confer similar regulation on a reporter gene. Mutation of a protein binding site that spans sequences from -16 to +11 in the DHFR promoter resulted in loss of the transcriptional increase at the G1/S boundary. Purification of an activity from HeLa nuclear extract that binds to this region enriched for a 180-kDa polypeptide (HIP1). Using this HIP1 preparation, we have identified specific positions within the binding site that are critical for efficient protein-DNA interactions. An analysis of association and dissociation rates suggests that bound HIP1 protein can exchange rapidly with free protein. This rapid exchange may facilitate the burst of transcriptional activity from the DHFR promoter at the G1/S boundary.

  17. The HIP1 binding site is required for growth regulation of the dihydrofolate reductase gene promoter.

    PubMed Central

    Means, A L; Slansky, J E; McMahon, S L; Knuth, M W; Farnham, P J

    1992-01-01

    The transcription rate of the dihydrofolate reductase (DHFR) gene increases at the G1/S boundary of the proliferative cell cycle. Through analysis of transiently and stably transfected NIH 3T3 cells, we have now demonstrated that DHFR promoter sequences extending from -270 to +20 are sufficient to confer similar regulation on a reporter gene. Mutation of a protein binding site that spans sequences from -16 to +11 in the DHFR promoter resulted in loss of the transcriptional increase at the G1/S boundary. Purification of an activity from HeLa nuclear extract that binds to this region enriched for a 180-kDa polypeptide (HIP1). Using this HIP1 preparation, we have identified specific positions within the binding site that are critical for efficient protein-DNA interactions. An analysis of association and dissociation rates suggests that bound HIP1 protein can exchange rapidly with free protein. This rapid exchange may facilitate the burst of transcriptional activity from the DHFR promoter at the G1/S boundary. Images PMID:1545788

  18. Promoter hypermethylation of mismatch repair gene hMLH1 predicts the clinical response of malignant astrocytomas to nitrosourea.

    PubMed

    Fukushima, Takao; Katayama, Yoichi; Watanabe, Takao; Yoshino, Atsuo; Ogino, Akiyoshi; Ohta, Takashi; Komine, Chiaki

    2005-02-15

    In certain types of human cancers, transcriptional inactivation of hMLH1 by promoter hypermethylation plays a causal role in the loss of mismatch repair functions that modulate cytotoxic pathways in response to DNA-damaging agents. The aim of the present study was to investigate the role of promoter methylation of the hMLH1 gene in malignant astrocytomas. We examined the hMLH1 promoter methylation in a homogeneous cohort of patients with 41 malignant astrocytomas treated by 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-2(2-chloroethyl)-3-nitrosourea chemotherapy in combination with radiation and interferon therapy, and assessed the correlation of such methylation with clinical outcome. hMLH1 promoter methylation was found in 6 (15%) of the 41 newly diagnosed malignant astrocytomas. Hypermethylation of the hMLH1 promoter corresponded closely with a loss of immunohistochemical staining for hMLH1 protein (P = 0.0013). Patients with hMLH1-methylated tumors displayed a greater chance of responding to adjuvant therapy as compared with those with hMLH1-unmethylated tumors (P = 0.0150). The presence of hMLH1 hypermethylation was significantly associated with a longer progression-free survival on both univariate analysis (P = 0.0340) and multivariate analysis (P = 0.0161). The present study identified hMLH1 methylation status as a predictor of the clinical response of malignant astrocytomas to chloroethylnitrosourea-based adjuvant therapy. The findings obtained suggest that determination of the methylation status of hMLH1 could provide a potential basis for designing rational chemotherapeutic strategies, as well as for predicting prognosis.

  19. A Baculovirus Immediate-Early Gene, ie1, Promoter Drives Efficient Expression of a Transgene in Both Drosophila melanogaster and Bombyx mori

    PubMed Central

    Masumoto, Mika; Ohde, Takahiro; Shiomi, Kunihiro; Yaginuma, Toshinobu; Niimi, Teruyuki

    2012-01-01

    Many promoters have been used to drive expression of heterologous transgenes in insects. One major obstacle in the study of non-model insects is the dearth of useful promoters for analysis of gene function. Here, we investigated whether the promoter of the immediate-early gene, ie1, from the Bombyx mori nucleopolyhedrovirus (BmNPV) could be used to drive efficient transgene expression in a wide variety of insects. We used a piggyBac-based vector with a 3xP3-DsRed transformation marker to generate a reporter construct; this construct was used to determine the expression patterns driven by the BmNPV ie1 promoter; we performed a detailed investigation of the promoter in transgene expression pattern in Drosophila melanogaster and in B. mori. Drosophila and Bombyx belong to different insect orders (Diptera and Lepidoptera, respectively); however, and to our surprise, ie1 promoter-driven expression was evident in several tissues (e.g., prothoracic gland, midgut, and tracheole) in both insects. Furthermore, in both species, the ie1 promoter drove expression of the reporter gene from a relatively early embryonic stage, and strong ubiquitous ie1 promoter-driven expression continued throughout the larval, pupal, and adult stages by surface observation. Therefore, we suggest that the ie1 promoter can be used as an efficient expression driver in a diverse range of insect species. PMID:23152896

  20. Estrogens and Progesterone Promote Persistent CCND1 Gene Activation during G1 by Inducing Transcriptional Derepression via c-Jun/c-Fos/Estrogen Receptor (Progesterone Receptor) Complex Assembly to a Distal Regulatory Element and Recruitment of Cyclin D1 to Its Own Gene Promoter

    PubMed Central

    Cicatiello, Luigi; Addeo, Raffaele; Sasso, Annarita; Altucci, Lucia; Petrizzi, Valeria Belsito; Borgo, Raphaelle; Cancemi, Massimo; Caporali, Simona; Caristi, Silvana; Scafoglio, Claudio; Teti, Diana; Bresciani, Francesco; Perillo, Bruno; Weisz, Alessandro

    2004-01-01

    Transcriptional activation of the cyclin D1 gene (CCND1) plays a pivotal role in G1-phase progression, which is thereby controlled by multiple regulatory factors, including nuclear receptors (NRs). Appropriate CCND1 gene activity is essential for normal development and physiology of the mammary gland, where it is regulated by ovarian steroids through a mechanism(s) that is not fully elucidated. We report here that CCND1 promoter activation by estrogens in human breast cancer cells is mediated by recruitment of a c-Jun/c-Fos/estrogen receptor α complex to the tetradecanoyl phorbol acetate-responsive element of the gene, together with Oct-1 to a site immediately adjacent. This process coincides with the release from the same DNA region of a transcriptional repressor complex including Yin-Yang 1 (YY1) and histone deacetylase 1 and is sufficient to induce the assembly of the basal transcription machinery on the promoter and to lead to initial cyclin D1 accumulation in the cell. Later on in estrogen stimulation, the cyclin D1/Cdk4 holoenzyme associates with the CCND1 promoter, where E2F and pRb can also be found, contributing to the long-lasting gene enhancement required to drive G1-phase completion. Interestingly, progesterone triggers similar regulatory events through its own NRs, suggesting that the gene regulation cascade described here represents a crossroad for the transcriptional control of G1-phase progression by different classes of NRs. PMID:15282324

  1. OSD1 promotes meiotic progression via APC/C inhibition and forms a regulatory network with TDM and CYCA1;2/TAM.

    PubMed

    Cromer, Laurence; Heyman, Jefri; Touati, Sandra; Harashima, Hirofumi; Araou, Emilie; Girard, Chloe; Horlow, Christine; Wassmann, Katja; Schnittger, Arp; De Veylder, Lieven; Mercier, Raphael

    2012-01-01

    Cell cycle control is modified at meiosis compared to mitosis, because two divisions follow a single DNA replication event. Cyclin-dependent kinases (CDKs) promote progression through both meiosis and mitosis, and a central regulator of their activity is the APC/C (Anaphase Promoting Complex/Cyclosome) that is especially required for exit from mitosis. We have shown previously that OSD1 is involved in entry into both meiosis I and meiosis II in Arabidopsis thaliana; however, the molecular mechanism by which OSD1 controls these transitions has remained unclear. Here we show that OSD1 promotes meiotic progression through APC/C inhibition. Next, we explored the functional relationships between OSD1 and the genes known to control meiotic cell cycle transitions in Arabidopsis. Like osd1, cyca1;2/tam mutation leads to a premature exit from meiosis after the first division, while tdm mutants perform an aberrant third meiotic division after normal meiosis I and II. Remarkably, while tdm is epistatic to tam, osd1 is epistatic to tdm. We further show that the expression of a non-destructible CYCA1;2/TAM provokes, like tdm, the entry into a third meiotic division. Finally, we show that CYCA1;2/TAM forms an active complex with CDKA;1 that can phosphorylate OSD1 in vitro. We thus propose that a functional network composed of OSD1, CYCA1;2/TAM, and TDM controls three key steps of meiotic progression, in which OSD1 is a meiotic APC/C inhibitor.

  2. Nurr1 promotes intestinal regeneration after ischemia/reperfusion injury by inhibiting the expression of p21 (Waf1/Cip1).

    PubMed

    Zu, Guo; Yao, Jihong; Ji, Anlong; Ning, Shili; Luo, Fuwen; Li, Zhenlu; Feng, Dongcheng; Rui, Yiqi; Li, Yang; Wang, Guangzhi; Tian, Xiaofeng

    2017-01-01

    Intestinal ischemia/reperfusion (I/R) injury is a potentially life-threatening condition that can cause injuries to remote organs at the end stage. The damage caused by intestinal I/R insult induces changes in the barrier functions of the intestine, and the intrinsic mechanism of regeneration is often insufficient to restore barrier functions, as indicated by the high mortality rate of patients experiencing intestinal I/R injury. However, little is known about the mechanisms of intestinal regeneration after I/R injury. Here, we reported that nuclear receptor-related protein 1 (Nurr1), a nuclear orphan receptor, was induced during intestinal regeneration after I/R. Our findings showed that Nurr1 expression was consistent with the expression of Ki-67 and phosphorylated histone H3 (pH 3) in the intestine after I/R injury. Nurr1 knockdown led to G1-phase arrest mediated by p21 (Waf1/Cip1) activation, but Nurr1 overexpression reduced the proportion of IEC-6 cells in G1 phase as a result of p21 inhibition in a p53-independent manner. Using chromatin immunoprecipitation assays, luciferase assays, and mutational analysis, we demonstrated that Nurr1 directly inhibited the transcription of p21. These results define a novel Nurr1/p21 pathway that is involved in intestinal regeneration after I/R injury. These findings provide novel molecular insights into the pathogenesis of intestinal regeneration after I/R and possibly support the development of new potential therapies for intestinal I/R injury. Nurr1 was induced during intestinal regeneration after I/R injury. Nurr1 promoted proliferation of intestinal epithelial cells after H/R injury. Nurr1 inhibited p21 expression in a p53-independent manner. Nurr1 inhibited p21 gene transcription by binding to p21 promoter directly.

  3. Dimethylglycine Provides Salt and Temperature Stress Protection to Bacillus subtilis

    PubMed Central

    Bashir, Abdallah; Hoffmann, Tamara; Smits, Sander H. J.

    2014-01-01

    Glycine betaine is a potent osmotic and thermal stress protectant of many microorganisms. Its synthesis from glycine results in the formation of the intermediates monomethylglycine (sarcosine) and dimethylglycine (DMG), and these compounds are also produced when it is catabolized. Bacillus subtilis does not produce sarcosine or DMG, and it cannot metabolize these compounds. Here we have studied the potential of sarcosine and DMG to protect B. subtilis against osmotic, heat, and cold stress. Sarcosine, a compatible solute that possesses considerable protein-stabilizing properties, did not serve as a stress protectant of B. subtilis. DMG, on the other hand, proved to be only moderately effective as an osmotic stress protectant, but it exhibited good heat stress-relieving and excellent cold stress-relieving properties. DMG is imported into B. subtilis cells primarily under osmotic and temperature stress conditions via OpuA, a member of the ABC family of transporters. Ligand-binding studies with the extracellular solute receptor (OpuAC) of the OpuA system showed that OpuAC possesses a moderate affinity for DMG, with a Kd value of approximate 172 μM; its Kd for glycine betaine is about 26 μM. Docking studies using the crystal structures of the OpuAC protein with the sulfur analog of DMG, dimethylsulfonioacetate, as a template suggest a model of how the DMG molecule can be stably accommodated within the aromatic cage of the OpuAC ligand-binding pocket. Collectively, our data show that the ability to acquire DMG from exogenous sources under stressful environmental conditions helps the B. subtilis cell to cope with growth-restricting osmotic and temperature challenges. PMID:24561588

  4. A simplified characterization of S-adenosyl-l-methionine-consuming enzymes with 1-Step EZ-MTase: a universal and straightforward coupled-assay for in vitro and in vivo setting† †Electronic supplementary information (ESI) available: Experimental materials and methods, characterization of all compounds (1H–1H COSY NMR, 1H–13C edited HSQC NMR, MS analysis), supplementary figures and tables, worksheets for the 1-Step EZ-MTase assay using both UV- and fluorescence-detection mode, a worksheet for the determination of glycine N-methyltransferase activity within biological samples. Samples of purified TM0936 will be distributed upon request. See DOI: 10.1039/c7sc02830j

    PubMed Central

    Walters, Ryan O.; Huffman, Derek M.

    2017-01-01

    Methyltransferases use S-adenosyl-l-methionine (SAM) to deposit methyl marks. Many of these epigenetic ‘writers’ are associated with gene regulation. As cancer etiology is highly correlated with misregulated methylation patterns, methyltransferases are emerging therapeutic targets. Successful assignment of methyltransferases' roles within intricate biological networks relies on (1) the access to enzyme mechanistic insights and (2) the efficient screening of chemical probes against these targets. To characterize methyltransferases in vitro and in vivo, we report a highly-sensitive one-step deaminase-linked continuous assay where the S-adenosyl-l-homocysteine (SAH) enzyme-product is rapidly and quantitatively catabolized to S-inosyl-l-homocysteine (SIH). To highlight the broad capabilities of this assay, we established enzymatic characteristics of two protein arginine methyltransferases (PRMT5 and PRMT7), a histone-lysine N-methyltransferase (DIM-5) and a sarcosine/dimethylglycine N-methyltransferase (SDMT). Since the coupling deaminase TM0936 displays robust activity over a broad pH-range we determined the pH dependence of SDMT reaction rates. TM0936 reactions are monitored at 263 nm, so a drawback may arise when methyl acceptor substrates absorb within this UV-range. To overcome this limitation, we used an isosteric fluorescent SAM-analog: S-8-aza-adenosyl-l-methionine. Most enzymes tolerated this probe and sustained methyltransfers were efficiently monitored through loss of fluorescence at 360 nm. Unlike discontinuous radioactive- and antibody-based assays, our assay provides a simple, versatile and affordable approach towards the characterization of methyltransferases. Supported by three logs of linear dynamic range, the 1-Step EZ-MTase can detect methylation rates as low as 2 μM h–1, thus making it possible to quantify low nanomolar concentrations of glycine N-methyltransferase within crude biological samples. With Z′-factors above 0.75, this assay is

  5. Promoter/repressor system of Lactobacillus plantarum phage og1e: characterization of the promoters pR49-pR-pL and overproduction of the cro-like protein cng in Escherichia coli.

    PubMed

    Kakikawa, M; Watanabe, N; Funawatashi, T; Oki, M; Yasukawa, H; Taketo, A; Kodaira, K I

    1998-07-30

    The Lactobacillus plantarum phage og1e (42259bp) has two repressor-like genes cng and cpg oriented oppositely, accompanied by three potential promoters pR, pL and pR49, and seven operator-like sequences (GATAC-boxes) (Kodaira et al., 1997). In this study, the og1e putative promoters were introduced into the Escherichia coli promoter-detecting plasmid pKK232-8. In E. coli CK111, pR (pKPR1), pL (pKPL1) and pR49 (pKPR49) exhibited distinct CAT activities. When pKPR1 or pKPL1 was coexistent with a compatible plasmid pACYC184 carrying pR-cng (pA4PRCN1), the CAT activity was decreased significantly. On the other hand, cng directed a protein (Cng) of 10.1 kDa in E. coli under the control of T7 promoter. Gel mobility-shift assays demonstrated that Cng binds specifically to a DNA region containing the GATAC-boxes. In addition, primer extension analyses demonstrated that the two sequences pR and pL act as a promoter in L. plantarum as well as in E. coli. These results suggested that the potential promoters pR and pL probably function for the lytic and lysogenic pathways, respectively, and Cng may act as a repressor presumably through the GATAC-boxes as operators.

  6. Clinicopathological significance of plasminogen activator inhibitor-1 promoter 4G/5G polymorphism in breast cancer: a meta-analysis.

    PubMed

    Lee, Ju-Han; Kim, Younghye; Choi, Jung-Woo; Kim, Young-Sik

    2013-01-01

    Plasminogen activator inhibitor type 1 (PAI-1) is associated with poor prognosis in breast cancer. Transcriptional expression of the PAI-1 can be controlled by PAI-1 promoter 4G/5G polymorphism. However, the significance of PAI-1 promoter 4G/5G polymorphism in breast cancer patients is contentious. To address this controversy, we conducted a meta-analysis for the relationships between PAI-1 promoter polymorphism and clinicopathological characteristics of breast cancer. Relevant published studies were identified using a search of PubMed, Embase, and the ISI Web of Science. The effect sizes of PAI-1 promoter 4G/5G polymorphism on breast cancer risk, lymph node metastasis, histologic grade, and overall survival were calculated by odds ratio (OR) or hazard ratio. The effect sizes were combined using a random-effects model. Individuals with 4G/4G genotype had a higher risk of breast cancer than those with the combined 4G/5G and 5G/5G genotypes (OR = 1.388; p = 0.031). Breast cancer patients with the 5G/5G genotype displayed lymph node metastasis more than patients with either the combined other genotypes (OR = 1.495; p = 0.027) or with the 4G/4G genotype (OR = 1.623; p = 0.018). However, the PAI-1 promoter 4G/5G polymorphism was not associated with histological grade or overall survival. PAI-1 promoter 4G/5G polymorphism is associated with a relatively increased risk of breast cancer development and lymph node metastasis. Copyright © 2013 IMSS. Published by Elsevier Inc. All rights reserved.

  7. Prognostic role of APC and RASSF1A promoter methylation status in cell free circulating DNA of operable gastric cancer patients.

    PubMed

    Balgkouranidou, I; Matthaios, D; Karayiannakis, A; Bolanaki, H; Michailidis, P; Xenidis, N; Amarantidis, K; Chelis, L; Trypsianis, G; Chatzaki, E; Lianidou, E S; Kakolyris, S

    2015-08-01

    Gastric carcinogenesis is a multistep process including not only genetic mutations but also epigenetic alterations. The best known and more frequent epigenetic alteration is DNA methylation affecting tumor suppressor genes that may be involved in various carcinogenetic pathways. The aim of the present study was to investigate the methylation status of APC promoter 1A and RASSF1A promoter in cell free DNA of operable gastric cancer patients. Using methylation specific PCR, we examined the methylation status of APC promoter 1A and RASSF1A promoter in 73 blood samples obtained from patients with gastric cancer. APC and RASSF1A promoters were found to be methylated in 61 (83.6%) and 50 (68.5%) of the 73 gastric cancer samples examined, but in none of the healthy control samples (p < 0.001). A significant association between methylated RASSF1A promoter status and lymph node positivity was observed (p = 0.005). Additionally, a significant correlation between a methylated APC promoter and elevated CEA (p = 0.033) as well as CA-19.9 (p = 0.032) levels, was noticed. The Kaplan-Meier estimates of survival, significantly favored patients with a non-methylated APC promoter status (p = 0.008). No other significant correlations between APC and RASSF1A methylation status and different tumor variables examined was observed. Serum RASSF1A and APC promoter hypermethylation is a frequent epigenetic event in patients with early operable gastric cancer. The observed correlations between APC promoter methylation status and survival as well as between a hypermethylated RASSF1A promoter and nodal positivity may be indicative of a prognostic role for those genes in early operable gastric cancer. Additional studies, in a larger cohort of patients are required to further explore whether these findings could serve as potential molecular biomarkers of survival and/or response to specific treatments. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Id-1 promotes TGF-{beta}1-induced cell motility through HSP27 activation and disassembly of adherens junction in prostate epithelial cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Di Kaijun; Wong, Y.C.; Wang Xianghong

    Id-1 (inhibitor of differentiation or DNA binding-1) has been positively associated with cell proliferation, cell cycle progression, and invasiveness during tumorigenesis. In addition, Id-1 has been shown to modulate cellular sensitivity to TGF-{beta}1 (transforming growth factor {beta}1). Here we demonstrate a novel role of Id-1 in promoting TGF-{beta}1-induced cell motility in a non-malignant prostate epithelial cell line, NPTX. We found that Id-1 promoted F-actin stress fiber formation in response to TGF-{beta}1, which was associated with increased cell-substrate adhesion and cell migration in NPTX cells. In addition, this positive effect of Id-1 on TGF-{beta}1-induced cell motility was mediated through activation ofmore » MEK-ERK signaling pathway and subsequent phosphorylation of HSP27 (heat shock protein 27). Furthermore, Id-1 disrupted the adherens junction complex in TGF-{beta}1-treated cells through down-regulation of E-cadherin, redistribution of {beta}-catenin, along with up-regulation of N-cadherin. These lines of evidence reveal a novel tumorigenic role of Id-1 through reorganization of actin cytoskeleton and disassembly of cell-cell adhesion in response to TGF-{beta}1 in human prostate epithelial cells, and suggest that intracellular Id-1 levels might be a determining factor for switching TGF-{beta}1 from a growth inhibitor to a tumor promoter during prostate carcinogenesis.« less

  9. PD-L1 Expression Promotes Epithelial to Mesenchymal Transition in Human Esophageal Cancer.

    PubMed

    Chen, Lujun; Xiong, Yuqi; Li, Jing; Zheng, Xiao; Zhou, Qi; Turner, Abbey; Wu, Changping; Lu, Binfeng; Jiang, Jingting

    2017-01-01

    PD-L1 (Programmed cell death 1 ligand 1, PD-L1), an essential immune checkpoint molecule in the tumor microenvironment, is an important target for cancer immunotherapy. We have previously reported that its expression in human gastric and esophageal cancer tissues is significantly associated with cancer progression and patients' postoperative prognoses. Its expression in cancer cells is well known to inhibit the T cell-mediated anti-tumor response, and this mechanism of action has been targeted for cancer immunotherapy. As of now, the autonomous effect of PD-L1 on cancer cells is not well understood, thus our present study aimed to examine the role of PD-L1 intervention in cellular biological functions, especially epithelial to mesenchymal transition (EMT), of the human esophageal cancer cell line, Eca-109 cells. Immunohistochemistry assay was used to investigate the correlation between expression of PD-L1 and EMT markers in human esophageal cancer tissues. Intervention of PD-L1 by using RNAi and over-expression methods were used to study the role of PD-L1 in regulation of biological behaviors and EMT in Eca-109 cells. Our clinical and pathological data demonstrated that tumor samples in the EMT positive subgroup had higher PD-L1 expression than those in the EMT negative subgroup. By manipulating PD-L1 expression in Eca-109 cells either through ablation or overexpression of wild type and the cytoplasmic domain-truncated mutant, we demonstrated that PD-L1 expression significantly promoted the cell viability, migration and EMT phenotype. Furthermore, our study also indicated that PD-1 fusion protein mediated stimulation of PD-L1 and the cytoplasmic domain of PD-L1 played a critical role in promoting EMT phenotype of Eca-109 cells, thereby suggesting that PD-1 receptor usually by triggering the reverse signaling can effect PD-L1 mediated regulation of esophageal cancer cell response. Our present study reveals a tumor cell-autonomous role of PD-L1 signaling in promoting

  10. LuFLA1PRO and LuBGAL1PRO promote gene expression in the phloem fibres of flax (Linum usitatissimum).

    PubMed

    Hobson, Neil; Deyholos, Michael K

    2013-04-01

    Cell type-specific promoters were identified that drive gene expression in an industrially important product. To identify flax (Linum usitatissimum) gene promoters, we analyzed the genomic regions upstream of a fasciclin-like arabinogalactan protein (LuFLA1) and a beta-galactosidase (LuBGAL1). Both of these genes encode transcripts that have been found to be highly enriched in tissues bearing phloem fibres. Using a beta-glucuronidase (GUS) reporter construct, we found that a 908-bp genomic sequence upstream of LuFLA1 (LuFLA1PRO) directed GUS expression with high specificity to phloem fibres undergoing secondary cell wall development. The DNA sequence upstream of LuBGAL1 (LuBGAL1PRO) likewise produced GUS staining in phloem fibres with developing secondary walls, as well as in tissues of developing flowers and seed bolls. These data provide further evidence of a specific role for LuFLA1 in phloem fibre development, and demonstrate the utility of LuFLA1PRO and LuBGAL1PRO as tools for biotechnology and further investigations of phloem fibre development.

  11. tRNAs promote nuclear import of HIV-1 intracellular reverse transcription complexes.

    PubMed

    Zaitseva, Lyubov; Myers, Richard; Fassati, Ariberto

    2006-10-01

    Infection of non-dividing cells is a biological property of HIV-1 crucial for virus transmission and AIDS pathogenesis. This property depends on nuclear import of the intracellular reverse transcription and pre-integration complexes (RTCs/PICs). To identify cellular factors involved in nuclear import of HIV-1 RTCs, cytosolic extracts were fractionated by chromatography and import activity examined by the nuclear import assay. A near-homogeneous fraction was obtained, which was active in inducing nuclear import of purified and labeled RTCs. The active fraction contained tRNAs, mostly with defective 3' CCA ends. Such tRNAs promoted HIV-1 RTC nuclear import when synthesized in vitro. Active tRNAs were incorporated into and recovered from virus particles. Mutational analyses indicated that the anticodon loop mediated binding to the viral complex whereas the T-arm may interact with cellular factors involved in nuclear import. These tRNA species efficiently accumulated into the nucleus on their own in a energy- and temperature-dependent way. An HIV-1 mutant containing MLV gag did not incorporate tRNA species capable of inducing HIV-1 RTC nuclear import and failed to infect cell cycle-arrested cells. Here we provide evidence that at least some tRNA species can be imported into the nucleus of human cells and promote HIV-1 nuclear import.

  12. Sulforaphane inhibits CYP1A1 activity and promotes genotoxicity induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin in vitro

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yang, Fangxing, E-mail: fxyang@zju.edu.cn; Zhuang, Shulin; Zhang, Chao

    2013-06-15

    Increasing environmental pollution by carcinogens such as some of persistent organic pollutants (POPs) has prompted growing interest in searching for chemopreventive compounds which are readily obtainable. Sulforaphane (SFN) is isolated from cruciferous vegetables and has the potentials to reduce carcinogenesis through various pathways. In this study, we studied the effects of SFN on CYP1A1 activity and genotoxicity induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). The results showed that SFN inhibited TCDD-induced CYP1A1 activity in H4IIE cells by directly inhibiting CYP1A1 activity, probably through binding to aryl hydrocarbon receptor and/or CYP1A1 revealed by molecular docking. However, SFN promoted TCDD-induced DNA damage in yeast cellsmore » and reduced the viability of initiated yeast cells. Besides, it is surprising that SFN also failed to reduce genotoxicity induced by other genotoxic reagents which possess different mechanisms to lead to DNA damage. Currently, it is difficult to predict whether SFN has the potentials to reduce the risk of TCDD based on the conflicting observations in the study. Therefore, further studies should be urgent to reveal the function and mechanism of SFN in the stress of such POPs on human health. - Highlights: • Sulforaphane inhibited TCDD-induced CYP1A1 activity in H4IIE cells. • Sulforaphane may bind to aryl hydrocarbon receptor and/or CYP1A1. • Sulforaphane promoted TCDD-induced DNA damage in yeast cells. • Sulforaphane may promote DNA damage by DNA strand breaks or DNA alkylation.« less

  13. Promoter of lncRNA Gene PVT1 Is a Tumor-Suppressor DNA Boundary Element. | Office of Cancer Genomics

    Cancer.gov

    Noncoding mutations in cancer genomes are frequent but challenging to interpret. PVT1 encodes an oncogenic lncRNA, but recurrent translocations and deletions in human cancers suggest alternative mechanisms. Here, we show that the PVT1 promoter has a tumor-suppressor function that is independent of PVT1 lncRNA. CRISPR interference of PVT1 promoter enhances breast cancer cell competition and growth in vivo.

  14. Rictor forms a complex with Cullin-1 to promote SGK1 ubiquitination and destruction

    PubMed Central

    Gao, Daming; Wan, Lixin; Inuzuka, Hiroyuki; Berg, Anders H.; Tseng, Alan; Zhai, Bo; Shaik, Shavali; Bennett, Eric; Tron, Adriana E.; Gasser, Jessica A.; Lau, Alan; Gygi, Steven; Harper, J. Wade; DeCaprio, James A.; Toker, Alex; Wei, Wenyi

    2010-01-01

    Summary The Rictor/mTOR complex (also known as mTORC2) plays a critical role in cellular homeostasis by phosphorylating AGC kinases such as Akt and SGK at their hydrophobic motifs to activate downstream signaling. However, the regulation of mTORC2 and whether it has additional function(s), remains largely unknown. Here we report that Rictor associates with Cullin-1 to form a functional E3 ubiquitin ligase. Rictor, but not Raptor or mTOR alone promotes SGK1 ubiquitination. Loss of Rictor/Cullin-1-mediated ubiquitination leads to increased SGK1 protein levels as detected in Rictor null cells. Moreover, as part of a feedback mechanism, phosphorylation of Rictor at T1135 by multiple AGC kinases disrupts the interaction between Rictor and Cullin-1 to impair SGK1 ubiquitination. These findings indicate that the Rictor/Cullin-1 E3 ligase activity is regulated by a specific signal relay cascade and that misregulation of this mechanism may contribute to the frequent overexpression of SGK1 in various human cancers. PMID:20832730

  15. SMAD3 augments FoxO3-induced MuRF-1 promoter activity in a DNA-binding-dependent manner

    PubMed Central

    Bollinger, Lance M.; Witczak, Carol A.; Houmard, Joseph A.

    2014-01-01

    Muscle-specific RING finger-1 (MuRF-1), a ubiquitin ligase and key regulator of proteasome-dependent protein degradation, is highly expressed during skeletal muscle atrophy. The transcription factor forkhead box O3 (FoxO3) induces MuRF-1 expression, but the direct role of other major atrophy-related transcription factors, such as SMAD3, is largely unknown. The goal of this study was to determine whether SMAD3 individually regulates, or with FoxO3 coordinately regulates, MuRF-1 expression. In cultured myotubes or human embryonic kidney cells, MuRF-1 mRNA content and promoter activity were increased by FoxO3 but not by SMAD3 overexpression. However, FoxO3 and SMAD3 coexpression synergistically increased MuRF-1 mRNA and promoter activity. Mutation of the SMAD-binding element (SBE) in the proximal MuRF-1 promoter or overexpression of a SMAD3 DNA-binding mutant attenuated FoxO3-dependent MuRF-1 promoter activation, showing that SMAD binding to DNA is required for optimal activation of FoxO3-induced transcription of MuRF-1. Using chromatin immunoprecipitation, SMAD3 DNA binding increased FoxO3 abundance and SBE mutation reduced FoxO3 abundance on the MuRF-1 promoter. Furthermore, SMAD3 overexpression dose-dependently increased FoxO3 protein content, and coexpression of FoxO3 and SMAD3 synergistically increased FoxO-dependent gene transcription [assessed with a FoxO response element (FRE)-driven reporter]. Collectively, these results show that SMAD3 regulates transcription of MuRF-1 by increasing FoxO3 binding at a conserved FRE-SBE motif within the proximal promoter region, and by increasing FoxO3 protein content and transcriptional activity. These data are the first to indicate that two major transcription factors regulating protein degradation, FoxO3 and SMAD3, converge to coordinately and directly regulate transcription of MuRF-1. PMID:24920680

  16. Essential and Unexpected Role of YY1 to Promote Mesodermal Cardiac Differentiation

    PubMed Central

    Gregoire, Serge; Karra, Ravi; Passer, Derek; Deutsch, Marcus-Andre; Krane, Markus; Feistritzer, Rebecca; Sturzu, Anthony; Domian, Ibrahim; Saga, Yumiko; Wu, Sean M.

    2013-01-01

    Rational Cardiogenesis is regulated by a complex interplay between transcription factors. However, little is known about how these interactions regulate the transition from mesodermal precursors to cardiac progenitor cells (CPCs). Objective To identify novel regulators of mesodermal cardiac lineage commitment. Methods and Results We performed a bioinformatic-based transcription factor binding site analysis on upstream promoter regions of genes that are enriched in embryonic stem cell (ESC)-derived CPCs. From 32 candidate transcription factors screened, we found that YY1, a repressor of sarcomeric gene expression, is present in CPCs in vivo. Interestingly, we uncovered the ability of YY1 to transcriptionally activate Nkx2.5, a key marker of early cardiogenic commitment. YY1 regulates Nkx2.5 expression via a 2.1 kb cardiac-specific enhancer as demonstrated by in vitro luciferase-based assays and in vivo chromatin immunoprecipitation (ChIP) and genome-wide sequencing analysis. Furthermore, the ability of YY1 to activate Nkx2.5 expression depends on its cooperative interaction with Gata4 at a nearby chromatin. Cardiac mesoderm-specific loss-of-function of YY1 resulted in early embryonic lethality. This was corroborated in vitro by ESC-based assays where we show that the overexpression of YY1 enhanced the cardiogenic differentiation of ESCs into CPCs. Conclusion These results demonstrate an essential and unexpected role for YY1 to promote cardiogenesis as a transcriptional activator of Nkx2.5 and other CPC-enriched genes. PMID:23307821

  17. Microsatellite polymorphism in the P1 promoter region of the IGF-1 gene is associated with endometrial cancer

    PubMed Central

    KWASNIEWSKI, WOJCIECH; GOZDZICKA-JOZEFIAK, ANNA; WOLUN-CHOLEWA, MARIA; POLAK, GRZEGORZ; SIEROCINSKA-SAWA, JADWIGA; KWASNIEWSKA, ANNA; KOTARSKI, JAN

    2016-01-01

    Endometrial carcinoma (EC) is the most common type of gynecological malignancy. Studies have demonstrated that the insulin growth factor (IGF) pathway is implicated in the development of endometrial tumors and that the serum levels of IGF-1 are affected by estrogen. Most EC cells with high microsatellite instability (MSI-H) accumulate mutations at a microsatellite sequence in the IGF-1 gene. The present study investigated the CA repeat polymorphism in the P1 promoter region of the IGF-1 gene among Caucasian females with endometrial hyperplasia, EC and healthy control subjects, whose blood serum and surgical tissue specimens were analyzed. Differences or correlations between the analyzed parameters [serum levels of IGF-1 and IGF binding protein (IGFBP)-1 and IGFBP-3 as well as estrogens among the polymorphisms] were verified using the χ2, Mann-Whitney U, Kruskal-Wallis or Spearman's rank correlation tests. A PCR amplification and DNA sequencing analysis was used for identification of (CA)n repeats in the P1 region of IGF-1. ELISA was used to determine the blood serum levels of IGF-1, IGFBP-1, IGFBP-3 and estrogens. Furthermore, IGF-1 was assessed in endometrial tissues by immunohistochemical analysis. The present study indicated no statistically significant differences between serum levels of IGF-1, IGFBP-1, IGFBP-3 and estrone, estriol and estradiol in the control and study groups. A significant correlation was identified between the IGF-1 levels and estrone levels in the MSI-H polymorphism (r=−0.41, P=0.012) as well as a highly negative correlation between IGF-1 levels and the estradiol levels in the MSI-H polymorphism (r=−0.6, P=0.002). Genotypes without the 19 CA allele were predominantly found in EC. Furthermore, statistical analysis indicated that the number of IGF-1-expressing cells was significantly elevated in MSI-H type 18-20 (P= 0.0072), MSI-L type 19-20 (P=0.025) and microsatellite-stable MSS type 19-19 (P=0.024) compared with those in the MSI-H 20

  18. MACF1 Overexpression by Transfecting the 21 kbp Large Plasmid PEGFP-C1A-ACF7 Promotes Osteoblast Differentiation and Bone Formation.

    PubMed

    Zhang, Yan; Yin, Chong; Hu, Lifang; Chen, Zhihao; Zhao, Fan; Li, Dijie; Ma, Jianhua; Ma, Xiaoli; Su, Peihong; Qiu, Wuxia; Yang, Chaofei; Wang, Pai; Li, Siyu; Zhang, Ge; Wang, Liping; Qian, Airong; Xian, Cory J

    2018-02-01

    Microtubule actin crosslinking factor 1 (MACF1) is a large spectraplakin protein known to have crucial roles in regulating cytoskeletal dynamics, cell migration, growth, and differentiation. However, its role and action mechanism in bone remain unclear. The present study investigated optimal conditions for effective transfection of the large plasmid PEGFP-C1A-ACF7 (∼21 kbp) containing full-length human MACF1 cDNA, as well as the potential role of MACF1 in bone formation. To enhance MACF1 expression, the plasmid was transfected into osteogenic cells by electroporation in vitro and into mouse calvaria with nanoparticles. Then, transfection efficiency, osteogenic marker expression, calvarial thickness, and bone formation were analyzed. Notably, MACF1 overexpression triggered a drastic increase in osteogenic gene expression, alkaline phosphatase activity, and matrix mineralization in vitro. Mouse calvarial thickness, mineral apposition rate, and osteogenic marker protein expression were significantly enhanced by local transfection. In addition, MACF1 overexpression promoted β-catenin expression and signaling. In conclusion, MACF1 overexpression by transfecting the large plasmid containing full-length MACF1 cDNA promotes osteoblast differentiation and bone formation via β-catenin signaling. Current data will provide useful experimental parameters for the transfection of large plasmids and a novel strategy based on promoting bone formation for prevention and therapy of bone disorders.

  19. Cell cycle in egg cell and its progression during zygotic development in rice.

    PubMed

    Sukawa, Yumiko; Okamoto, Takashi

    2018-03-01

    Rice egg is arrested at G1 phase probably by OsKRP2. After fusion with sperm, karyogamy, OsWEE1-mediated parental DNA integrity in zygote nucleus, zygote progresses cell cycle to produce two-celled embryo. In angiosperms, female and male gametes exist in gametophytes after the complementation of meiosis and the progression of nuclear/cell division of the haploid cell. Within the embryo sac, the egg cell is specially differentiated for fertilization and subsequent embryogenesis, and cellular programs for embryonic development, such as restarting the cell cycle and de novo gene expression, are halted. There is only limited knowledge about how the cell cycle in egg cells restarts toward zygotic division, although the conversion of the cell cycle from a quiescent and arrested state to an active state is the most evident transition of cell status from egg cell to zygote. This is partly due to the difficulty in direct access and analysis of egg cells, zygotes and early embryos, which are deeply embedded in ovaries. In this study, precise relative DNA amounts in the nuclei of egg cells, developing zygotes and cells of early embryos were measured, and the cell cycle of a rice egg cell was estimated as the G1 phase with a 1C DNA level. In addition, increases in DNA content in zygote nuclei via karyogamy and DNA replication were also detectable according to progression of the cell cycle. In addition, expression profiles for cell cycle-related genes in egg cells and zygotes were also addressed, and it was suggested that OsKRP2 and OsWEE1 function in the inhibition of cell cycle progression in egg cells and in checkpoint of parental DNA integrity in zygote nucleus, respectively.

  20. Identification of constitutional MLH1 epimutations and promoter variants in colorectal cancer patients from the Colon Cancer Family Registry

    PubMed Central

    Ward, Robyn L.; Dobbins, Timothy; Lindor, Noralane M.; Rapkins, Robert W.; Hitchins, Megan P.

    2013-01-01

    Purpose: Constitutional MLH1 epimutations manifest as promoter methylation and silencing of the affected allele in normal tissues, predisposing to Lynch syndrome–associated cancers. This study investigated their frequency and inheritance. Methods: A total of 416 individuals with a colorectal cancer showing loss of MLH1 expression and without deleterious germline mutations in MLH1 were ascertained from the Colon Cancer Family Registry (C-CFR). Constitutive DNA samples were screened for MLH1 methylation in all 416 subjects and for promoter sequence changes in 357 individuals. Results: Constitutional MLH1 epimutations were identified in 16 subjects. Of these, seven (1.7%) had mono- or hemi-allelic methylation and eight had low-level methylation (2%). In one subject the epimutation was linked to the c.-27C>A promoter variant. Testing of 37 relatives from nine probands revealed paternal transmission of low-level methylation segregating with a c.+27G>A variant in one case. Five additional probands had a promoter variant without an MLH1 epimutation, with three showing diminished promoter activity in functional assays. Conclusion: Although rare, sequence changes in the regulatory region of MLH1 and aberrant methylation may alone or together predispose to the development of cancer. Screening for these changes is warranted in individuals who have a negative germline sequence screen of MLH1 and loss of MLH1 expression in their tumor. PMID:22878509

  1. Astrocyte Elevated Gene 1 Interacts with Acetyltransferase p300 and c-Jun To Promote Tumor Aggressiveness

    PubMed Central

    Liu, Liping; Guan, Hongyu; Li, Yun; Ying, Zhe; Wu, Jueheng; Zhu, Xun; Song, Libing

    2016-01-01

    ABSTRACT Astrocyte elevated gene 1 (AEG-1) is an oncoprotein that strongly promotes the development and progression of cancers. However, the detailed underlying mechanisms through which AEG-1 enhances tumor development and progression remain to be determined. In this study, we identified c-Jun and p300 to be novel interacting partners of AEG-1 in gliomas. AEG-1 promoted c-Jun transcriptional activity by interacting with the c-Jun/p300 complex and inducing c-Jun acetylation. Furthermore, the AEG-1/c-Jun/p300 complex was found to bind the promoter of c-Jun downstream targeted genes, consequently establishing an acetylated chromatin state that favors transcriptional activation. Importantly, AEG-1/p300-mediated c-Jun acetylation resulted in the development of a more aggressive malignant phenotype in gliomas through a drastic increase in glioma cell proliferation and angiogenesis in vitro and in vivo. Consistently, the AEG-1 expression levels in clinical glioma specimens correlated with the status of c-Jun activation. Taken together, our results suggest that AEG-1 mediates a novel epigenetic mechanism that enhances c-Jun transcriptional activity to induce glioma progression and that AEG-1 might be a novel, potential target for the treatment of gliomas. PMID:27956703

  2. Casein Kinase II Regulation of the Hot1 Transcription Factor Promotes Stochastic Gene Expression*

    PubMed Central

    Burns, Laura T.; Wente, Susan R.

    2014-01-01

    In Saccharomyces cerevisiae, Hog1 MAPK is activated and induces a transcriptional program in response to hyperosmotic stress. Several Hog1-responsive genes exhibit stochastic transcription, resulting in cell-to-cell variability in mRNA and protein levels. However, the mechanisms governing stochastic gene activity are not fully defined. Here we uncover a novel role for casein kinase II (CK2) in the cellular response to hyperosmotic stress. CK2 interacts with and phosphorylates the Hot1 transcription factor; however, Hot1 phosphorylation is not sufficient for controlling the stochastic response. The CK2 protein itself is required to negatively regulate mRNA expression of Hot1-responsive genes and Hot1 enrichment at target promoters. Single-cell gene expression analysis reveals altered activation of Hot1-targeted STL1 in ck2 mutants, resulting in a bimodal to unimodal shift in expression. Together, this work reveals a novel CK2 function during the hyperosmotic stress response that promotes cell-to-cell variability in gene expression. PMID:24817120

  3. Influenza A Virus NS1 Protein Promotes Efficient Nuclear Export of Unspliced Viral M1 mRNA.

    PubMed

    Pereira, Carina F; Read, Eliot K C; Wise, Helen M; Amorim, Maria J; Digard, Paul

    2017-08-01

    Influenza A virus mRNAs are transcribed by the viral RNA-dependent RNA polymerase in the cell nucleus before being exported to the cytoplasm for translation. Segment 7 produces two major transcripts: an unspliced mRNA that encodes the M1 matrix protein and a spliced transcript that encodes the M2 ion channel. Export of both mRNAs is dependent on the cellular NXF1/TAP pathway, but it is unclear how they are recruited to the export machinery or how the intron-containing but unspliced M1 mRNA bypasses the normal quality-control checkpoints. Using fluorescent in situ hybridization to monitor segment 7 mRNA localization, we found that cytoplasmic accumulation of unspliced M1 mRNA was inefficient in the absence of NS1, both in the context of segment 7 RNPs reconstituted by plasmid transfection and in mutant virus-infected cells. This effect was independent of any major effect on steady-state levels of segment 7 mRNA or splicing but corresponded to a ∼5-fold reduction in the accumulation of M1. A similar defect in intronless hemagglutinin (HA) mRNA nuclear export was seen with an NS1 mutant virus. Efficient export of M1 mRNA required both an intact NS1 RNA-binding domain and effector domain. Furthermore, while wild-type NS1 interacted with cellular NXF1 and also increased the interaction of segment 7 mRNA with NXF1, mutant NS1 polypeptides unable to promote mRNA export did neither. Thus, we propose that NS1 facilitates late viral gene expression by acting as an adaptor between viral mRNAs and the cellular nuclear export machinery to promote their nuclear export. IMPORTANCE Influenza A virus is a major pathogen of a wide variety of mammalian and avian species that threatens public health and food security. A fuller understanding of the virus life cycle is important to aid control strategies. The virus has a small genome that encodes relatively few proteins that are often multifunctional. Here, we characterize a new function for the NS1 protein, showing that, as well as

  4. Human TERT promoter mutation enables survival advantage from MGMT promoter methylation in IDH1 wild-type primary glioblastoma treated by standard chemoradiotherapy.

    PubMed

    Nguyen, HuyTram N; Lie, Amy; Li, Tie; Chowdhury, Reshmi; Liu, Fei; Ozer, Byram; Wei, Bowen; Green, Richard M; Ellingson, Benjamin M; Wang, He-Jing; Elashoff, Robert; Liau, Linda M; Yong, William H; Nghiemphu, Phioanh L; Cloughesy, Timothy; Lai, Albert

    2017-03-01

    Promoter mutation in the human telomerase reverse transcriptase gene (hTERT) occurs in ~75% of primary glioblastoma (GBM). Although the mutation appears to upregulate telomerase expression and contributes to the maintenance of telomere length, its clinical significance remains unclear. We performed hTERT promoter genotyping on 303 isocitrate dehydrogenase 1 wild-type GBM tumors treated with standard chemoradiotherapy. We also stratified 190 GBM patients from the database of The Cancer Genome Atlas (TCGA) by hTERT gene expression. We analyzed overall and progression-free survival by Kaplan-Meier and Cox regression. We detected hTERT promoter mutation in 75% of the patients. When included as the only biomarker, hTERT mutation was not prognostic in our patient cohort by Cox regression analysis. However, when hTERT and O6-DNA methylguanine-methyltransferase (MGMT) were included together, we observed an interaction between these 2 factors. To further investigate this interaction, we performed pairwise comparison of the 4 patient subcohorts grouped by hTERT-MGMT status (MUT-M, WT-M, MUT-U, and WT-U). MGMT methylated patients showed improved survival only in the presence of hTERT promoter mutation: MUT-M versus MUT-U (overall survival of 28.3 vs 15.9 mos, log-rank P < .0001 and progression-free survival of 15.4 vs 7.86 mo, log-rank P < .0001). These results were confirmed by Cox analyses. Analogously, the cohort from TCGA demonstrated survival benefit of MGMT promoter methylation only in patients with high hTERT expression. In addition, hTERT mutation was negatively prognostic in our MGMT unmethylated patients, while the analogous association with high expression was not observed in the cohort from TCGA. The prognostic influence of MGMT promoter methylation depends on hTERT promoter mutation. This interaction warrants further mechanistic investigation. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights

  5. Regulation of HFE expression by Poly(ADP-ribose) polymerase-1 (PARP1) through an inverted repeat DNA sequence in the distal promoter

    PubMed Central

    Rodova, Marianna; Rudolph, Angela; Chipps, Elizabeth; Islam, M. Rafiq

    2013-01-01

    Hereditary hemochromatosis (HH) is a common autosomal recessive disorder of iron overload among Caucasians of northern European descent. Over 85% of all cases with HH are due to mutations in the hemochromatosis protein (HFE) involved in iron metabolism. Although the importance in iron homeostasis is well recognized, the mechanism of sensing and regulating iron absorption by HFE, especially in the absence of iron response element in its gene, is not fully understood. In this report, we have identified an inverted repeat sequence (ATGGTcttACCTA) within 1700 bp (−1675/+35) of the HFE promoter capable to form cruciform structure that binds PARP1 and strongly represses HFE promoter. Knockdown of PARP1 increases HFE mRNA and protein. Similarly, hemin or FeCl3 treatments resulted in increase in HFE expression by reducing nuclear PARP1 pool via its apoptosis induced cleavage, leading to upregulation of the iron regulatory hormone hepcidin mRNA. Thus, PARP1 binding to the inverted repeat sequence on the HFE promoter may serve as a novel iron sensing mechanism as increased iron level can trigger PARP1 cleavage and relief of HFE transcriptional repression. PMID:24184271

  6. Regulation of HFE expression by poly(ADP-ribose) polymerase-1 (PARP1) through an inverted repeat DNA sequence in the distal promoter.

    PubMed

    Pelham, Christopher; Jimenez, Tamara; Rodova, Marianna; Rudolph, Angela; Chipps, Elizabeth; Islam, M Rafiq

    2013-12-01

    Hereditary hemochromatosis (HH) is a common autosomal recessive disorder of iron overload among Caucasians of northern European descent. Over 85% of all cases with HH are due to mutations in the hemochromatosis protein (HFE) involved in iron metabolism. Although the importance in iron homeostasis is well recognized, the mechanism of sensing and regulating iron absorption by HFE, especially in the absence of iron response element in its gene, is not fully understood. In this report, we have identified an inverted repeat sequence (ATGGTcttACCTA) within 1700bp (-1675/+35) of the HFE promoter capable to form cruciform structure that binds PARP1 and strongly represses HFE promoter. Knockdown of PARP1 increases HFE mRNA and protein. Similarly, hemin or FeCl3 treatments resulted in increase in HFE expression by reducing nuclear PARP1 pool via its apoptosis induced cleavage, leading to upregulation of the iron regulatory hormone hepcidin mRNA. Thus, PARP1 binding to the inverted repeat sequence on the HFE promoter may serve as a novel iron sensing mechanism as increased iron level can trigger PARP1 cleavage and relief of HFE transcriptional repression. © 2013.

  7. AML1/ETO trans-activates c-KIT expression through the long range interaction between promoter and intronic enhancer.

    PubMed

    Tian, Ying; Wang, Genjie; Hu, Qingzhu; Xiao, Xichun; Chen, Shuxia

    2018-04-01

    The AML1/ETO onco-fusion protein is crucial for the genesis of t(8;21) acute myeloid leukemia (AML) and is well documented as a transcriptional repressor through dominant-negative effect. However, little is known about the transactivation mechanism of AML1/ETO. Through large cohort of patient's expression level data analysis and a series of experimental validation, we report here that AML1/ETO transactivates c-KIT expression through directly binding to and mediating the long-range interaction between the promoter and intronic enhancer regions of c-KIT. Gene expression analyses verify that c-KIT expression is significantly high in t(8;21) AML. Further ChIP-seq analysis and motif scanning identify two regulatory regions located in the promoter and intronic enhancer region of c-KIT, respectively. Both regions are enriched by co-factors of AML1/ETO, such as AML1, CEBPe, c-Jun, and c-Fos. Further luciferase reporter assays show that AML1/ETO trans-activates c-KIT promoter activity through directly recognizing the AML1 motif and the co-existence of co-factors. The induction of c-KIT promoter activity is reinforced with the existence of intronic enhancer region. Furthermore, ChIP-3C-qPCR assays verify that AML1/ETO mediates the formation of DNA-looping between the c-KIT promoter and intronic enhancer region through the long-range interaction. Collectively, our data uncover a novel transcriptional activity mechanism of AML1/ETO and enrich our knowledge of the onco-fusion protein mediated transcription regulation. © 2017 Wiley Periodicals, Inc.

  8. Polycystin-1 promotes PKC{alpha}-mediated NF-{kappa}B activation in kidney cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Banzi, Manuela; Aguiari, Gianluca; Trimi, Viky

    2006-11-17

    Polycystin-1 (PC1), the PKD1 gene product, is a membrane receptor which regulates many cell functions, including cell proliferation and apoptosis, both typically increased in cyst lining cells in autosomal dominant polycystic kidney disease. Here we show that PC1 upregulates the NF-{kappa}B signalling pathway in kidney cells to prevent cell death. Human embryonic kidney cell lines (HEK293{sup CTT}), stably expressing a PC1 cytoplasmic terminal tail (CTT), presented increased NF-{kappa}B nuclear levels and NF-{kappa}B-mediated luciferase promoter activity. This, consistently, was reduced in HEK293 cells in which the endogenous PC1 was depleted by RNA interference. CTT-dependent NF-{kappa}B promoter activation was mediated by PKC{alpha}more » because it was blocked by its specific inhibitor Ro-320432. Furthermore, it was observed that apoptosis, which was increased in PC1-depleted cells, was reduced in HEK293{sup CTT} cells and in porcine kidney LtTA cells expressing a doxycycline-regulated CTT. Staurosporine, a PKC inhibitor, and parthenolide, a NF-{kappa}B inhibitor, significantly reduced the CTT-dependent antiapoptotic effect. These data reveal, therefore, a novel pathway by which polycystin-1 activates a PKC{alpha}-mediated NF-{kappa}B signalling and cell survival.« less

  9. O-GlcNAcylation of histone deacetylases 1 in hepatocellular carcinoma promotes cancer progression.

    PubMed

    Zhu, Guizhou; Tao, Tao; Zhang, Dongmei; Liu, Xiaojuan; Qiu, Huiyuan; Han, LiJian; Xu, Zhiwei; Xiao, Ying; Cheng, Chun; Shen, Aiguo

    2016-08-01

    Hepatocellular carcinoma (HCC) is a malignant tumor originating in the liver. Previous studies have indicated that O-GlcNAc transferase (OGT) and histone deacetylase-1 (HDAC1) play important roles in the pathogenesis of HCC. In the present study, we investigated the physical link between OGT and HDAC1. The O-GlcNAcylation of HDAC1 is overexpressed in HCC. We found that HDAC1 has two major sites of O-GlcNAcylation in its histone deacetylase domain. HDAC1 O-GlcNAcylation increases the activated phosphorylation of HDAC1, which enhances its enzyme activity. HDAC1 O-GlcNAc mutants promote the p21 transcription regulation through affecting the acetylation levels of histones from chromosome, and then influence the proliferation of HCC cells. We also found that mutants of O-GlcNAcylation site of HDAC1 affect invasion and migration of HepG2 cells. E-cadherin level is highly up-regulated in HDAC1 O-GlcNAc mutant-treated liver cancer cells, which inhibit the occurrence and development of HCC. Our findings suggest that OGT promotes the O-GlcNAc modification of HDAC1in the development of HCC. Therefore, inhibiting O-GlcNAcylation of HDAC1 may repress the progression of HCC. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. TaALMT1 promoter sequence compositions, acid tolerance, and Al tolerance in wheat cultivars and landraces from Sichuan in China.

    PubMed

    Han, C; Dai, S F; Liu, D C; Pu, Z J; Wei, Y M; Zheng, Y L; Wen, D J; Zhao, L; Yan, Z H

    2013-11-18

    Previous genetic studies on wheat from various sources have indicated that aluminum (Al) tolerance may have originated independently in USA, Brazil, and China. Here, TaALMT1 promoter sequences of 92 landraces and cultivars from Sichuan, China, were sequenced. Five promoter types (I', II, III, IV, and V) were observed in 39 cultivars, and only three promoter types (I, II, and III) were observed in 53 landraces. Among the wheat collections worldwide, only the Chinese Spring (CS) landrace native to Sichuan, China, carried the TaALMT1 promoter type III. Besides CS, two other Sichuan-bred landraces and six cultivars with TaALMT1 promoter type III were identified in this study. In the phylogenetic tree constructed based on the TaALMT1 promoter sequences, type III formed a separate branch, which was supported by a high bootstrap value. It is likely that TaALMT1 promoter type III originated from Sichuan-bred wheat landraces of China. In addition, the landraces with promoter type I showed the lowest Al tolerance among all landraces and cultivars. Furthermore, the cultivars with promoter type IV showed better Al tolerance than landraces with promoter type II. A comparison of acid tolerance and Al tolerance between cultivars and landraces showed that the landraces had better acid tolerance than the cultivars, whereas the cultivars showed better Al tolerance than the landraces. Moreover, significant difference in Al tolerance was also observed between the cultivars raised by the National Ministry of Agriculture and by Sichuan Province. Among the landraces from different regions, those from the East showed better acid tolerance and Al tolerance than those from the South and West of Sichuan. Additional Al-tolerant and acid-tolerant wheat lines were also identified.

  11. Tubulin polymerization promoting protein 1 (Tppp1) phosphorylation by Rho-associated coiled-coil kinase (rock) and cyclin-dependent kinase 1 (Cdk1) inhibits microtubule dynamics to increase cell proliferation.

    PubMed

    Schofield, Alice V; Gamell, Cristina; Suryadinata, Randy; Sarcevic, Boris; Bernard, Ora

    2013-03-15

    Tubulin polymerization promoting protein 1 (Tppp1) regulates microtubule (MT) dynamics via promoting MT polymerization and inhibiting histone deacetylase 6 (Hdac6) activity to increase MT acetylation. Our results reveal that as a consequence, Tppp1 inhibits cell proliferation by delaying the G1/S-phase and the mitosis to G1-phase transitions. We show that phosphorylation of Tppp1 by Rho-associated coiled-coil kinase (Rock) prevents its Hdac6 inhibitory activity to enable cells to enter S-phase. Whereas, our analysis of the role of Tppp1 during mitosis revealed that inhibition of its MT polymerizing and Hdac6 regulatory activities were necessary for cells to re-enter the G1-phase. During this investigation, we also discovered that Tppp1 is a novel Cyclin B/Cdk1 (cyclin-dependent kinase) substrate and that Cdk phosphorylation of Tppp1 inhibits its MT polymerizing activity. Overall, our results show that dual Rock and Cdk phosphorylation of Tppp1 inhibits its regulation of the cell cycle to increase cell proliferation.

  12. Critical Role of HAX-1 in Promoting Avian Influenza Virus Replication in Lung Epithelial Cells

    PubMed Central

    He, Ganlin; Cardona, Carol J.

    2018-01-01

    The PB1-F2 protein of influenza A virus has been considered a virulence factor, but its function in inducing apoptosis may be of disadvantage to viral replication. Host mechanisms to regulate PB1-F2-induced apoptosis remain unknown. We generated a PB1-F2-deficient avian influenza virus (AIV) H9N2 and found that the mutant virus replicated less efficiently in human lung epithelial cells. The PB1-F2-deficient virus produced less apoptotic cells, indicating that PB1-F2 of the H9N2 virus promotes apoptosis, occurring at the early stage of infection, in the lung epithelial cells. To understand how host cells regulate PB1-F2-induced apoptosis, we explored to identify cellular proteins interacting with PB1-F2 and found that HCLS1-associated protein X-1 (HAX-1), located mainly in the mitochondria as an apoptotic inhibitor, interacted with PB1-F2. Increased procaspase-9 activations, induced by PB1-F2, could be suppressed by HAX-1. In HAX-1 knockdown A549 cells, the replication of AIV H9N2 was suppressed in parallel to the activation of caspase-3 activation, which increased at the early stage of infection. We hypothesize that HAX-1 promotes AIV replication by interacting with PB1-F2, resulting in the suppression of apoptosis, prolonged cell survival, and enhancement of viral replication. Our data suggest that HAX-1 may be a promoting factor for AIV H9N2 replication through desensitizing PB1-F2 from its apoptotic induction in human lung epithelial cells. PMID:29576744

  13. Blockade of Tumor-Expressed PD-1 promotes lung cancer growth

    PubMed Central

    Du, Shisuo; McCall, Neal; Park, Kyewon; Guan, Qing; Fontina, Paolo; Ertel, Adam; Zhan, Tingting; Dicker, Adam P.; Lu, Bo

    2018-01-01

    ABSTRACT Anti-PD-1 immunotherapy is the standard of care for treating many patients with non-small cell lung cancer (NSCLC), yet mechanisms of treatment failure are emerging. We present a case of NSCLC, who rapidly progressed during a trial (NCT02318771) combining palliative radiotherapy and pembrolizumab. Planned tumor biopsy demonstrated PD-1 expression by NSCLC cells. We validated this observation by detecting PD-1 transcript in lung cancer cells and by co-localizing PD-1 and lung cancer-specific markers in resected lung cancer tissues. We further investigated the biological role of cancer-intrinsic PD-1 in a mouse lung cancer cell line, M109. Knockout or antibody blockade of PD-1 enhanced M109 viability in-vitro, while PD-1 overexpression and exposure to recombinant PD-L1 diminished viability. PD-1 blockade accelerated growth of M109-xenograft tumors with increased proliferation and decreased apoptosis in immune-deficient mice. This represents a first-time report of NSCLC-intrinsic PD-1 expression and a potential mechanism by which PD-1 blockade may promote cancer growth. PMID:29632720

  14. OTX1 promotes colorectal cancer progression through epithelial-mesenchymal transition

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yu, Kun; Cai, Xin-Yi; Li, Qiang

    2014-01-31

    Highlights: • OTX1 is overexpression in colorectal cancer tissues. • Overexpression of OTX1 promotes colorectal cancer cell proliferation and invasion in vitro and tumor growth in vivo. • Depletion of OTX1 inhibits colorectal cancer cell proliferation and invasion in vitro. • Overexpression of OTX1 is linked to the EMT-like phenotype. - Abstract: Orthodenticle homeobox 1 (OTX1), a transcription factor containing a bicoid-like homeodomain, plays a role in brain and sensory organ development. In this study, we report that OTX1 is overexpressed in human colorectal cancer (CRC) and OTX1 overexpression is associated with higher stage. Functional analyses reveal that overexpression ofmore » OTX1 results in accumulation of CRC cell proliferation and invasion in vitro and tumor growth in vivo, whereas ablation of OTX1 expression significantly inhibits the proliferative and invasive capability of CRC cells in vitro. Together, our results indicate that OTX1 is involved in human colon carcinogenesis and may serve as a potential therapeutic target for human colorectal cancer.« less

  15. Blockade of Tumor-Expressed PD-1 promotes lung cancer growth.

    PubMed

    Du, Shisuo; McCall, Neal; Park, Kyewon; Guan, Qing; Fontina, Paolo; Ertel, Adam; Zhan, Tingting; Dicker, Adam P; Lu, Bo

    2018-01-01

    Anti-PD-1 immunotherapy is the standard of care for treating many patients with non-small cell lung cancer (NSCLC), yet mechanisms of treatment failure are emerging. We present a case of NSCLC, who rapidly progressed during a trial (NCT02318771) combining palliative radiotherapy and pembrolizumab. Planned tumor biopsy demonstrated PD-1 expression by NSCLC cells. We validated this observation by detecting PD-1 transcript in lung cancer cells and by co-localizing PD-1 and lung cancer-specific markers in resected lung cancer tissues. We further investigated the biological role of cancer-intrinsic PD-1 in a mouse lung cancer cell line, M109. Knockout or antibody blockade of PD-1 enhanced M109 viability in-vitro, while PD-1 overexpression and exposure to recombinant PD-L1 diminished viability. PD-1 blockade accelerated growth of M109-xenograft tumors with increased proliferation and decreased apoptosis in immune-deficient mice. This represents a first-time report of NSCLC-intrinsic PD-1 expression and a potential mechanism by which PD-1 blockade may promote cancer growth.

  16. A Rb1 promoter variant with reduced activity contributes to osteosarcoma susceptibility in irradiated mice

    PubMed Central

    2014-01-01

    Background Syndromic forms of osteosarcoma (OS) account for less than 10% of all recorded cases of this malignancy. An individual OS predisposition is also possible by the inheritance of low penetrance alleles of tumor susceptibility genes, usually without evidence of a syndromic condition. Genetic variants involved in such a non-syndromic form of tumor predisposition are difficult to identify, given the low incidence of osteosarcoma cases and the genetic heterogeneity of patients. We recently mapped a major OS susceptibility QTL to mouse chromosome 14 by comparing alpha-radiation induced osteosarcoma in mouse strains which differ in their tumor susceptibility. Methods Tumor-specific allelic losses in murine osteosacoma were mapped along chromosome 14 using microsatellite markers and SNP allelotyping. Candidate gene search in the mapped interval was refined using PosMed data mining and mRNA expression analysis in normal osteoblasts. A strain-specific promoter variant in Rb1 was tested for its influence on mRNA expression using reporter assay. Results A common Rb1 allele derived from the BALB/cHeNhg strain was identified as the major determinant of radiation-induced OS risk at this locus. Increased OS-risk is linked with a hexanucleotide deletion in the promoter region which is predicted to change WT1 and SP1 transcription factor-binding sites. Both in-vitro reporter and in-vivo expression assays confirmed an approx. 1.5 fold reduced gene expression by this promoter variant. Concordantly, the 50% reduction in Rb1 expression in mice bearing a conditional hemizygous Rb1 deletion causes a significant rise of OS incidence following alpha-irradiation. Conclusion This is the first experimental demonstration of a functional and genetic link between reduced Rb1 expression from a common promoter variant and increased tumor risk after radiation exposure. We propose that a reduced Rb1 expression by common variants in regulatory regions can modify the risk for a malignant

  17. Effects of Gene Orientation and Use of Multiple Promoters on the Expression of XYL1 and XYL2 in Saccharomyces cerevisiae

    NASA Astrophysics Data System (ADS)

    Bae, Ju Yun; Laplaza, José; Jeffries, Thomas W.

    Orientation of adjacent genes has been reported to affect their expression in eukaryotic systems, and metabolic engineering also often makes repeated use of a few promoters to obtain high expression. To improve transcriptional control in heterologous expression, we examined how these factors affect gene expression and enzymatic activity in Saccharomyces cerevisiae. We assembled d-xylose reductase (XYL1) and d-xylitol dehydrogenase (XYL2) in four ways. Each pair of genes was placed in two different tandem (l→2→ or √1√2), convergent (1→√2), and divergent (√1 2→) orientations in autonomous plasmids. The TEF1 promoter was used to drive XYL1 and the TDH3 promoter to drive XYL2 in each of the constructs. The effects of gene orientation on growth, transcription, and enzyme activity were analyzed. The transcription level as measured by quantitative PCR (q-PCR) correlated with enzyme activities, but our data did not show a significant effect of gene orientation. To test the possible dilution of promoter strength due to multiple use of the same promoter, we examined the level of expression of XYL1 driven by either the TEF1 or TDH3 promoter when carried on a single copy plasmid. We then coexpressed XYL2 from either a single or multicopy plasmid, which was also driven by the same promoter. XYL2 transcript and enzyme expression increased with plasmid copy number, while the expression of XYLl was constant regardless of the number of other TEF1 or TDH3 promoters present in the cell. According to our data, there is no significant effect of gene orientation or multiple promoter use on gene transcription and translation when genes are expressed from plasmids; however, other factors could affect expression of adjacent genes in chromosomes.

  18. Lentiviral Gene Therapy Using Cellular Promoters Cures Type 1 Gaucher Disease in Mice

    PubMed Central

    Dahl, Maria; Doyle, Alexander; Olsson, Karin; Månsson, Jan-Eric; Marques, André R A; Mirzaian, Mina; Aerts, Johannes M; Ehinger, Mats; Rothe, Michael; Modlich, Ute; Schambach, Axel; Karlsson, Stefan

    2015-01-01

    Gaucher disease is caused by an inherited deficiency of the enzyme glucosylceramidase. Due to the lack of a fully functional enzyme, there is progressive build-up of the lipid component glucosylceramide. Insufficient glucosylceramidase activity results in hepatosplenomegaly, cytopenias, and bone disease in patients. Gene therapy represents a future therapeutic option for patients unresponsive to enzyme replacement therapy and lacking a suitable bone marrow donor. By proof-of-principle experiments, we have previously demonstrated a reversal of symptoms in a murine disease model of type 1 Gaucher disease, using gammaretroviral vectors harboring strong viral promoters to drive glucosidase β-acid (GBA) gene expression. To investigate whether safer vectors can correct the enzyme deficiency, we utilized self-inactivating lentiviral vectors (SIN LVs) with the GBA gene under the control of human phosphoglycerate kinase (PGK) and CD68 promoter, respectively. Here, we report prevention of, as well as reversal of, manifest disease symptoms after lentiviral gene transfer. Glucosylceramidase activity above levels required for clearance of glucosylceramide from tissues resulted in reversal of splenomegaly, reduced Gaucher cell infiltration and a restoration of hematological parameters. These findings support the use of SIN-LVs with cellular promoters in future clinical gene therapy protocols for type 1 Gaucher disease. PMID:25655314

  19. The transcription factor CCAAT-binding factor CBF/NF-Y regulates the proximal promoter activity in the human alpha 1(XI) collagen gene (COL11A1).

    PubMed

    Matsuo, Noritaka; Yu-Hua, Wang; Sumiyoshi, Hideaki; Sakata-Takatani, Keiko; Nagato, Hitoshi; Sakai, Kumiko; Sakurai, Mami; Yoshioka, Hidekatsu

    2003-08-29

    We have characterized the proximal promoter region of the human COL11A1 gene. Transient transfection assays indicate that the segment from -199 to +1 is necessary for the activation of basal transcription. Electrophoretic mobility shift assays (EMSAs) demonstrated that the ATTGG sequence, within the -147 to -121 fragment, is critical to bind nuclear proteins in the proximal COL11A1 promoter. We demonstrated that the CCAAT binding factor (CBF/NF-Y) bound to this region using an interference assay with consensus oligonucleotides and a supershift assay with specific antibodies in an EMSA. In a chromatin immunoprecipitation assay and EMSA using DNA-affinity-purified proteins, CBF/NF-Y proteins directly bound this region in vitro and in vivo. We also showed that four tandem copies of the CBF/NF-Y-binding fragment produced higher transcriptional activity than one or two copies, whereas the absence of a CBF/NF-Y-binding fragment suppressed the COL11A1 promoter activity. Furthermore, overexpression of a dominant-negative CBF-B/NF-YA subunit significantly inhibited promoter activity in both transient and stable cells. These results indicate that the CBF/NF-Y proteins regulate the transcription of COL11A1 by directly binding to the ATTGG sequence in the proximal promoter region.

  20. Comprehensive analysis of the MLH1 promoter region in 480 patients with colorectal cancer and 1150 controls reveals new variants including one with a heritable constitutional MLH1 epimutation.

    PubMed

    Morak, Monika; Ibisler, Ayseguel; Keller, Gisela; Jessen, Ellen; Laner, Andreas; Gonzales-Fassrainer, Daniela; Locher, Melanie; Massdorf, Trisari; Nissen, Anke M; Benet-Pagès, Anna; Holinski-Feder, Elke

    2018-04-01

    Germline defects in MLH1 , MSH2 , MSH6 and PMS2 predisposing for Lynch syndrome (LS) are mainly based on sequence changes, whereas a constitutional epimutation of MLH1 (CEM) is exceptionally rare. This abnormal MLH1 promoter methylation is not hereditary when arising de novo, whereas a stably heritable and variant-induced CEM was described for one single allele. We searched for MLH1 promoter variants causing a germline or somatic methylation induction or transcriptional repression. We analysed the MLH1 promoter sequence in five different patient groups with colorectal cancer (CRC) (n=480) composed of patients with i) CEM (n=16), ii) unsolved loss of MLH1 expression in CRC (n=37), iii) CpG-island methylator-phenotype CRC (n=102), iv) patients with LS (n=83) and v) MLH1-proficient CRC (n=242) as controls. 1150 patients with non-LS tumours also served as controls to correctly judge the results. We detected 10 rare MLH1 promoter variants. One novel, complex MLH1 variant c.-63_-58delins18 is present in a patient with CRC with CEM and his sister, both showing a complete allele-specific promoter methylation and transcriptional silencing. The other nine promoter variants detected in 17 individuals were not associated with methylation. For four of these, a normal, biallelic MLH1 expression was found in the patients' cDNA. We report the second promoter variant stably inducing a hereditary CEM. Concerning the classification of promoter variants, we discuss contradictory results from the literature for two variants, describe classification discrepancies between existing rules for five variants, suggest the (re-)classification of five promoter variants to (likely) benign and regard four variants as functionally unclear. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  1. TGF-β promotes glioma cell growth via activating Nodal expression through Smad and ERK1/2 pathways

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sun, Jing; Liu, Su-zhi; Lin, Yan

    Highlights: •TGF-β promoted Nodal expression in glioma cells. •TGF-β promoted Nodal expression via activating Smad and ERK1/2 pathways. •TGF-β promotes glioma cell growth via activating Nodal expression. -- Abstract: While there were certain studies focusing on the mechanism of TGF-β promoting the growth of glioma cells, the present work revealed another novel mechanism that TGF-β may promote glioma cell growth via enhancing Nodal expression. Our results showed that Nodal expression was significantly upregulated in glioma cells when TGF-β was added, whereas the TGF-β-induced Nodal expression was evidently inhibited by transfection Smad2 or Smad3 siRNAs, and the suppression was especially significantmore » when the Smad3 was downregulated. Another, the attenuation of TGF-β-induced Nodal expression was observed with blockade of the ERK1/2 pathway also. Further detection of the proliferation, apoptosis, and invasion of glioma cells indicated that Nodal overexpression promoted the proliferation and invasion of tumor cells and inhibited their apoptosis, resembling the effect of TGF-β addition. Downregulation of Nodal expression via transfection Nodal-specific siRNA in the presence of TGF-β weakened the promoting effect of the latter on glioma cells growth, and transfecting Nodal siRNA alone in the absence of exogenous TGF-β more profoundly inhibited the growth of glioma cells. These results demonstrated that while both TGF-β and Nodal promoted glioma cells growth, the former might exert such effect by enhancing Nodal expression, which may form a new target for glioma therapy.« less

  2. HDM2 promotes WIP1-mediated medulloblastoma growth

    PubMed Central

    Buss, Meghan C.; Read, Tracy-Ann; Schniederjan, Matthew J.; Gandhi, Khanjan; Castellino, Robert C.

    2012-01-01

    Medulloblastoma is the most common malignant childhood brain tumor. The protein phosphatase and oncogene WIP1 is over-expressed or amplified in a significant number of primary human medulloblastomas and cell lines. In the present study, we examine an important mechanism by which WIP1 promotes medulloblastoma growth using in vitro and in vivo models. Human cell lines and intracerebellar xenografted animal models were used to study the role of WIP1 and the major TP53 regulator, HDM2, in medulloblastoma growth. Stable expression of WIP1 enhances growth of TP53 wild-type medulloblastoma cells, compared with cells with stable expression of an empty-vector or mutant WIP1. In an animal model, WIP1 enhances proliferation and reduces the survival of immunodeficient mice bearing intracerebellar xenografted human medulloblastoma cells. Cells with increased WIP1 expression also exhibit increased expression of HDM2. HDM2 knockdown or treatment with the HDM2 inhibitor Nutlin-3a, the active enantomer of Nutlin-3, specifically inhibits the growth of medulloblastoma cells with increased WIP1 expression. Nutlin-3a does not affect growth of medulloblastoma cells with stable expression of an empty vector or of mutant WIP1. Knockdown of WIP1 or treatment with the WIP1 inhibitor CCT007093 results in increased phosphorylation of known WIP1 targets, reduced HDM2 expression, and reduced growth specifically in WIP1 wild-type and high-expressing medulloblastoma cells. Combined WIP1 and HDM2 inhibition is more effective than WIP1 inhibition alone in blocking growth of WIP1 high-expressing medulloblastoma cells. Our preclinical study supports a role for therapies that target WIP1 and HDM2 in the treatment of medulloblastoma. PMID:22379189

  3. Epigenetic marker (LINE-1 promoter) methylation level was associated with occupational lead exposure.

    PubMed

    Li, Chunping; Yang, Xiaolin; Xu, Ming; Zhang, Jinlong; Sun, Na

    2013-05-01

    Occupational and environmental exposures to lead (Pb) are a worldwide concern. DNA methylation plays an important role in the development of Pb toxicity. Here, we try to find out the evidence to prove that the methylation of the LINE-1 promoter may be involved in Pb toxicity. To determine whether the methylation level of the LINE-1 is associated with the risk of Pb poisoning, we first constructed a Pb acetate-treated cell model to detect the association between LINE-1 methylation and Pb exposure. A case-control study involving 53 workers from a battery plant and 57 healthy volunteers with matching age and gender distribution was carried out. We employed methylation-specific real-time PCR to determine the relationship between LINE-1 methylation level and Pb exposure. In the cell model, Pb exposure significantly decreased the level of LINE-1 methylation (p = 0.009). Significant difference in methylation frequencies was found between the exposed and control samples (p < 0.001). We also found a decreasing trend of LINE-1 methylation level with increasing blood Pb level (p < 0.001). Therefore, the LINE-1 promoter methylation might contribute to the risk of Pb poisoning and identified a possible epigenetic biomarker for Pb toxicity, especially in individuals occupationally exposed to Pb.

  4. IGFBP1 increases β-cell regeneration by promoting α- to β-cell transdifferentiation.

    PubMed

    Lu, Jing; Liu, Ka-Cheuk; Schulz, Nadja; Karampelias, Christos; Charbord, Jérémie; Hilding, Agneta; Rautio, Linn; Bertolino, Philippe; Östenson, Claes-Göran; Brismar, Kerstin; Andersson, Olov

    2016-09-15

    There is great interest in therapeutically harnessing endogenous regenerative mechanisms to increase the number of β cells in people with diabetes. By performing whole-genome expression profiling of zebrafish islets, we identified 11 secreted proteins that are upregulated during β-cell regeneration. We then tested the proteins' ability to potentiate β-cell regeneration in zebrafish at supraphysiological levels. One protein, insulin-like growth factor (Igf) binding-protein 1 (Igfbp1), potently promoted β-cell regeneration by potentiating α- to β-cell transdifferentiation. Using various inhibitors and activators of the Igf pathway, we show that Igfbp1 exerts its regenerative effect, at least partly, by inhibiting Igf signaling. Igfbp1's effect on transdifferentiation appears conserved across species: Treating mouse and human islets with recombinant IGFBP1 in vitro increased the number of cells co-expressing insulin and glucagon threefold. Moreover, a prospective human study showed that having high IGFBP1 levels reduces the risk of developing type-2 diabetes by more than 85%. Thus, we identify IGFBP1 as an endogenous promoter of β-cell regeneration and highlight its clinical importance in diabetes. © 2016 The Authors. Published under the terms of the CC BY NC ND 4.0 license.

  5. Identification of HMX1 target genes: A predictive promoter model approach

    PubMed Central

    Boulling, Arnaud; Wicht, Linda

    2013-01-01

    Purpose A homozygous mutation in the H6 family homeobox 1 (HMX1) gene is responsible for a new oculoauricular defect leading to eye and auricular developmental abnormalities as well as early retinal degeneration (MIM 612109). However, the HMX1 pathway remains poorly understood, and in the first approach to better understand the pathway’s function, we sought to identify the target genes. Methods We developed a predictive promoter model (PPM) approach using a comparative transcriptomic analysis in the retina at P15 of a mouse model lacking functional Hmx1 (dmbo mouse) and its respective wild-type. This PPM was based on the hypothesis that HMX1 binding site (HMX1-BS) clusters should be more represented in promoters of HMX1 target genes. The most differentially expressed genes in the microarray experiment that contained HMX1-BS clusters were used to generate the PPM, which was then statistically validated. Finally, we developed two genome-wide target prediction methods: one that focused on conserving PPM features in human and mouse and one that was based on the co-occurrence of HMX1-BS pairs fitting the PPM, in human or in mouse, independently. Results The PPM construction revealed that sarcoglycan, gamma (35kDa dystrophin-associated glycoprotein) (Sgcg), teashirt zinc finger homeobox 2 (Tshz2), and solute carrier family 6 (neurotransmitter transporter, glycine) (Slc6a9) genes represented Hmx1 targets in the mouse retina at P15. Moreover, the genome-wide target prediction revealed that mouse genes belonging to the retinal axon guidance pathway were targeted by Hmx1. Expression of these three genes was experimentally validated using a quantitative reverse transcription PCR approach. The inhibitory activity of Hmx1 on Sgcg, as well as protein tyrosine phosphatase, receptor type, O (Ptpro) and Sema3f, two targets identified by the PPM, were validated with luciferase assay. Conclusions Gene expression analysis between wild-type and dmbo mice allowed us to develop a PPM

  6. Epigenetic activation of SIN1 promotes NSCLC cell proliferation and metastasis by affecting the epithelial–mesenchymal transition

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hu, Zhongwu; Wang, Yaqin; Wang, Yuemei

    Stress-activated protein kinase (SAPK) interacting protein 1 (SIN1) is an essential component of mTORC2. Previous studies have shown that SIN1 is a key regulator of Akt pathway which plays an important role in various pathological conditions including cancer. While its effects and mechanisms on the progression of NSCLC remain unknown. In this study, we report that SIN1 is able to promote the growth and migration of NSCLC cells both in vitro and in vivo. Overexpression of SIN1 promoted A549 and H1299 cells proliferation by both MTT and colony formation assays. Consistently, knockdown of SIN1 inhibited the proliferation of these cells. In transwell assay,more » overexpression of SIN1 increased the migration of A549 and H1299 cells, while SIN1 knockdown reduced their migration. In a tumor xenograft model, overexpression of SIN1 promoted tumor growth of A549 cells in vivo, while SIN1 knockdown suppresses the tumor growth. We also found a mechanistic link between SIN1 and H3K4me3, H3K4me3 is involved in SIN1 upregulation. Moreover, SIN1 can significantly promote the in vitro migration and invasion of NSCLC cells via induction epithelial mesenchymal transition (EMT) process, which subsequently leads to transcriptional downregulation of epithelial marker E-cadherin and upregulation of mesenchymal markers N-cadherin and Vimentin expression. Together, our results reveal that SIN1 plays an important role in NSCLC and SIN1 is a potential biomarker and a promising target in the treatment of NSCLC.« less

  7. A novel polymorphism in the PAI-1 gene promoter enhances gene expression. A novel pro-thrombotic risk factor?

    PubMed

    Liguori, Renato; Quaranta, Sandro; Di Fiore, Rosanna; Elce, Ausilia; Castaldo, Giuseppe; Amato, Felice

    2014-12-01

    Plasminogen activator inhibitor-1 (PAI-1) is the major physiological inhibitor of tissue-type plasminogen activator in plasma and the most important regulator of the fibrinolytic pathway. The 4G/5G polymorphism (rs1799889) in the PAI-1 promoter is associated with altered PAI-1 transcription. We have identified a new 4G/5G allele, in which a T is inserted near the 4G tract or replaces a G in the 5G tract, forming a T plus 4G (T4G) region. This new variant was first identified in two women, one had experienced juvenile myocardial infarction, the other repeated miscarriage; both had increased PAI-1 plasma activity. In view of the important influence of this promoter region on PAI-1 protein plasma level, we performed in vitro evaluation of the effects of the T4G variant on the transcription activity of the PAI-1 gene promoter. In silico prediction analysis showed that presence of the T4G allele disrupts the E-Box region upstream of the T4G variant, altering the affinity of the target sequence for E-Box binding factors like upstream stimulatory factor-1 (USF-1). Basal T4G promoter activity was 50% higher compared to 4G and 5G variants, but it was less stimulated by USF-1 overexpression. We also analyzed the effects of IL-1β and IL-6 on the PAI-1 promoter activity of our three constructs and showed that the T4G variant was less affected by IL-1β than the other variants. These findings indicate that the T4G variant may be a novel risk factor for thrombotic events. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Melanoma cell-intrinsic PD-1 receptor functions promote tumor growth

    PubMed Central

    Kleffel, Sonja; Posch, Christian; Barthel, Steven R.; Mueller, Hansgeorg; Schlapbach, Christoph; Guenova, Emmanuella; Elco, Christopher P.; Lee, Nayoung; Juneja, Vikram R.; Zhan, Qian; Lian, Christine G.; Thomi, Rahel; Hoetzenecker, Wolfram; Cozzio, Antonio; Dummer, Reinhard; Mihm, Martin C.; Flaherty, Keith T.; Frank, Markus H.; Murphy, George F.; Sharpe, Arlene H.; Kupper, Thomas S.; Schatton, Tobias

    2015-01-01

    SUMMARY Therapeutic antibodies targeting programmed cell death-1 (PD-1) activate tumor-specific immunity and have shown remarkable efficacy in the treatment of melanoma. Yet, little is known about tumor cell-intrinsic PD-1 pathway effects. Here we show that murine and human melanomas contain PD-1-expressing cancer subpopulations and demonstrate that melanoma cell-intrinsic PD-1 promotes tumorigenesis, even in mice lacking adaptive immunity. PD-1 inhibition on melanoma cells by RNA interference, blocking antibodies, or mutagenesis of melanoma-PD-1 signaling motifs suppresses tumor growth in immunocompetent, immunocompromised and PD-1-deficient tumor graft recipient mice. Conversely, melanoma-specific PD-1 overexpression enhances tumorigenicity, as does engagement of melanoma-PD-1 by its ligand, PD-L1, whereas melanoma-PD-L1 inhibition or knockout of host-PD-L1 attenuate growth of PD-1-positive melanomas. Mechanistically, the melanoma-PD-1 receptor modulates downstream effectors of mTOR signaling. Our results identify melanoma cell-intrinsic functions of the PD-1:PD-L1 axis in tumor growth and suggest that blocking melanoma-PD-1 might contribute to the striking clinical efficacy of anti-PD-1 therapy. PMID:26359984

  9. Organizational requirements of the SaeR binding sites for a functional P1 promoter of the sae operon in Staphylococcus aureus.

    PubMed

    Cho, Hoonsik; Jeong, Do-Won; Li, Chunling; Bae, Taeok

    2012-06-01

    In Staphylococcus aureus, the SaeRS two-component system controls the expression of multiple virulence factors. Of the two promoters in the sae operon, P1 is autoinduced and has two binding sites for the response regulator SaeR. In this study, we examined the organizational requirements of the SaeR binding sites in P1 for transcription activation. Mutational studies showed that both binding sites are essential for binding to phosphorylated SaeR (P-SaeR) and transcription activation. When the 21-bp distance between the centers of the two SaeR binding sites was altered to 26 bp, 31 bp, 36 bp, or 41 bp, only the 31-bp mutant retained approximately 40% of the original promoter activity. When the -1-bp spacing (i.e.,1-bp overlap) between the primary SaeR binding site and the -35 promoter region was altered, all mutant P1 promoters failed to initiate transcription; however, when the first nucleotide of the -35 region was changed from A to T, the mutants with 0-bp or 22-bp spacing showed detectable promoter activity. Although P-SaeR was essential for the binding of RNA polymerase to P1, it was not essential for the binding of the enzyme to the alpha-hemolysin promoter. When the nonoptimal spacing between promoter elements in P1 or the coagulase promoter was altered to the optimal spacing of 17 bp, both promoters failed to initiate transcription. These results suggest that SaeR binding sites are under rather strict organizational restrictions and provide clues for understanding the molecular mechanism of sae-mediated transcription activation.

  10. mTORC1 promotes T-bet phosphorylation to regulate Th1 differentiation

    PubMed Central

    Chornoguz, Olesya; Hagan, Robert S.; Haile, Azeb; Arwood, Matthew L.; Gamper, Christopher J.; Banerjee, Arnob; Powell, Jonathan D.

    2017-01-01

    CD4+ T cells lacking the mTORC1 activator Rheb fail to secrete IFNγ under Th1 polarizing conditions. We hypothesized that this phenotype is due to defects in regulation of the canonical Th1 transcription factor T-bet at the level of protein phosphorylation downstream of mTORC1. To test this hypothesis, we employed targeted mass-spectrometry proteomic analysis – multiple reaction monitoring mass spectrometry (MRM-MS). We used MRM-MS to detect and quantify predicted phospho-peptides derived from T-bet. By analyzing activated murine WT and Rheb deficient CD4+ T cells, as well as murine CD4+ T cells activated in the presence of rapamycin, a pharmacologic inhibitor of mTORC1, we were able to identify 6 T-bet phosphorylation sites. Five of these are novel, and 4 sites are consistently dephosphorylated in both Rheb deficient CD4+ T-cells and T-cells treated with rapamycin, suggesting mTORC1 signaling controls their phosphorylation. Alanine mutagenesis of each of the 6 phosphorylation sites was tested for the ability to impair IFNγ expression. Single phosphorylation site mutants still support induction of IFNγ expression, however simultaneous mutation of 3 of the mTORC1-dependent sites results in significantly reduced IFNγ expression. The reduced activity of the triple mutant T-bet is associated with its failure to recruit chromatin remodeling complexes to the Ifng gene promoter. These results establish a novel mechanism by which mTORC1 regulates Th1 differentiation, through control of T-bet phosphorylation. PMID:28424242

  11. Hox proteins activate the IGFBP-1 promoter and suppress the function of hPR in human endometrial cells.

    PubMed

    Gao, Jiaguo; Mazella, James; Tseng, Linda

    2002-11-01

    Previous studies have shown that progestin activates the transcription of IGFBP-1 (insulin-like growth factor binding protein-1). Four regions in the IGFBP-1 promotor have been identified to enhance the transcription. Two of the regions, located at -73 to -65 bp and -319 to -311 bp formed identical DNA-protein complexes with the nuclear extracts of endometrial stromal/decidual cells. To identify the binding protein(s) in endometrial cells that interact with these two regions, we have used the TGTCAATTA repeats (-319 to -11 bp of the IGFBP-1 promoter) to screen the human decidual cDNA library by yeast one-hybrid system. We found that Hox A10, HoxA11, HoxB2, HoxB4, and HoxD11 interacted with the TGTCAATTA repeats in yeast cells. Among these hox genes, the full-length coding region of HoxA10, HoxA11, and HoxB4 were used for functional analysis in three types of endometrial cells, undifferentiated endometrial stromal cells, decidual cells (differentiated stromal cells) and endometrial adenocarcinoma cell line (HEC1-B). All these endometrial cells produce IGFBP-1. Transient transfection assay showed that HoxA10 expression vector increased the promoter activity (the IGFBP-1 proximal promoter containing TGC/TCAATTA and two functional PRE sites) in endometrial stromal cells and in HEC-1B cells, but not in decidual cells. HoxB4 enhanced the promoter activity only in decidual cells, while HoxA11 had no apparent effect in all three types of cells. To evaluate whether Hox proteins would interact with progesterone receptor (hPR), cells were transfected with the promoter construct, Hox and hPR expression vectors. hPR alone activated the IGFBP-1 promoter activity, but expression of Hox gene suppressed the activation. Hox proteins also suppressed the hPR enhanced promoter activities of MMTV (containing consensus-PRE sites) and glycodelin (GdA, containing Sp1 site which mediates the hPR function). These data showed that Hox genes selectively activate the transcription of the IGFBP

  12. Cardiac-specific expression and hypertrophic upregulation of the feline Na(+)-Ca(2+) exchanger gene H1-promoter in a transgenic mouse model.

    PubMed

    Müller, Joachim G; Isomatsu, Yukihisa; Koushik, Srinagesh V; O'Quinn, Michael; Xu, Lin; Kappler, Christiana S; Hapke, Elizabeth; Zile, Michael R; Conway, Simon J; Menick, Donald R

    2002-02-08

    The NCX1 gene contains three promoters (H1, K1, and Br1), and as a result of alternative promoter usage and alternative splicing, there are multiple tissue-specific variants of the Na(+)-Ca(2+) exchanger. We have proposed that for NCX1, the H1 promoter regulates expression in the heart, the K1 promoter regulates expression in the kidney, and the Br1 promoter regulates expression in the brain as well as low-level ubiquitous expression. Here, using a transgenic mouse model, we test the role of the DNA region including -1831 to 67 bp of intron 1, encompassing exon H1 of the feline NCX1 gene (NCX1H1). The NCX1H1 promoter was sufficient for driving the normal spatiotemporal pattern of NCX1 expression in cardiac development. The luciferase reporter gene was expressed in a heart-restricted pattern both in early embryos (embryonic days 8 to 14) and in later embryos (after embryonic day 14), when NCX1 is also expressed in other tissues. In the adult, no luciferase activity was detected in the kidney, liver, spleen, uterus, or skeletal muscle; minimal activity was detected in the brain; and very high levels of luciferase expression were detected in the heart. Transverse aortic constriction-operated mice showed significantly increased left ventricular mass after 7 days. In addition, there was a 2-fold upregulation of NCX1H1 promoter activity in the left ventricle in animals after 7 days of pressure overload compared with both control and sham-operated animals. This work demonstrates that the NCX1H1 promoter directs cardiac-specific expression of the exchanger in both the embryo and adult and is also sufficient for the upregulation of NCX1 in response to pressure overload.

  13. Histone Deacetylase-1 Is Enriched at the Platelet-derived Growth Factor-D Promoter in Response to Interleukin-1β and Forms a Cytokine-inducible Gene-silencing Complex with NF-κB p65 and Interferon Regulatory Factor-1*

    PubMed Central

    Liu, Mary Y.; Khachigian, Levon M.

    2009-01-01

    Understanding the mechanisms governing cytokine control of growth factor expression in smooth muscle cells would provide invaluable insight into the molecular regulation of vascular phenotypes and create future opportunities for therapeutic intervention. Here, we report that the proinflammatory cytokine interleukin (IL)-1β suppresses platelet-derived growth factor (PDGF)-D promoter activity and mRNA and protein expression in smooth muscle cells. NF-κB p65, induced by IL-1β, interacts with a novel element in the PDGF-D promoter and inhibits PDGF-D transcription. Interferon regulatory factor-1 (IRF-1) is also induced by IL-1β and binds to a different element upstream in the promoter. Immunoprecipitation and chromatin immunoprecipitation experiments showed that IL-1β stimulates p65 interaction with IRF-1 and the accumulation of both factors at the PDGF-D promoter. Mutation of the IRF-1 and p65 DNA-binding elements relieved the promoter from IL-1β-mediated repression. PDGF-D repression by IL-1β involves histone deacetylation and interaction of HDAC-1 with IRF-1 and p65. HDAC-1 small interfering RNA ablates complex formation with IRF-1 and p65 and abrogates IRF-1 and p65 occupancy of the PDGF-D promoter. Thus, HDAC-1 is enriched at the PDGF-D promoter in cells exposed to IL-1β and forms a cytokine-inducible gene-silencing complex with p65 and IRF-1. PMID:19843519

  14. PARP1 restricts Epstein Barr Virus lytic reactivation by binding the BZLF1 promoter.

    PubMed

    Lupey-Green, Lena N; Moquin, Stephanie A; Martin, Kayla A; McDevitt, Shane M; Hulse, Michael; Caruso, Lisa B; Pomerantz, Richard T; Miranda, Jj L; Tempera, Italo

    2017-07-01

    The Epstein Barr virus (EBV) genome persists in infected host cells as a chromatinized episome and is subject to chromatin-mediated regulation. Binding of the host insulator protein CTCF to the EBV genome has an established role in maintaining viral latency type, and in other herpesviruses, loss of CTCF binding at specific regions correlates with viral reactivation. Here, we demonstrate that binding of PARP1, an important cofactor of CTCF, at the BZLF1 lytic switch promoter restricts EBV reactivation. Knockdown of PARP1 in the Akata-EBV cell line significantly increases viral copy number and lytic protein expression. Interestingly, CTCF knockdown has no effect on viral reactivation, and CTCF binding across the EBV genome is largely unchanged following reactivation. Moreover, EBV reactivation attenuates PARP activity, and Zta expression alone is sufficient to decrease PARP activity. Here we demonstrate a restrictive function of PARP1 in EBV lytic reactivation. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  15. Expression and promoter DNA methylation of MLH1 in colorectal cancer and lung cancer.

    PubMed

    Ma, Yunxia; Chen, Yuan; Petersen, Iver

    2017-04-01

    Aberrant DNA methylation is a common molecular feature in human cancer. The aims of this study were to analyze the methylation status of MLH1, one of the DNA mismatch repair (MMR) genes, in human colorectal and lung cancer and to evaluate its clinical relevance. The expression of MLH1 was analyzed in 8 colorectal cancer (CRC) and 8 lung cancer cell lines by real-time RT-PCR and western blotting. The MLH1 protein expression was evaluated by immunohistochemistry on tissue microarrays including 121 primary CRC and 90 lung cancer patient samples. In cancer cell lines, the methylation status of MLH1 promoter and exon 2 was investigated by bisulfite sequencing (BS). Methylation-specific-PCR (MSP) was used to evaluate methylation status of MLH1. The expression of MLH1 mRNA was detected in 8 CRC cell lines as well as normal colonic fibroblast cells CCD-33Co. At protein levels, MLH1 was lost in one CRC cell line HCT-116 and normal cells CCD-33Co. No methylation was found in the promoter and exon 2 of MLH1 in CRC cell lines. MLH1 was expressed in 8 lung cancer cell lines at both mRNA and protein levels. Compared to cancer cells, normal bronchial epithelial cells (HBEC) had lower expression of MLH1 protein. In primary CRC, 54.5% of cases exhibited positive staining, while 47.8% of lung tumors were positive for MLH1 protein. MSP analysis showed that 58 out of 92 (63.0%) CRC and 41 out of 73 (56.2%) lung cancer exhibited MLH1 methylation. In CRC, the MLH1 methylation was significantly associated with tumor invasion in veins (P=0.012). However, no significant links were found between MLH1 expression and promoter methylation in both tumor entities. MLH1 methylation is a frequent molecular event in CRC and lung cancer patients. In CRC, methylation of MLH1 could be linked to vascular invasiveness. Copyright © 2017 Elsevier GmbH. All rights reserved.

  16. Heme Oxygenase-1 Promotes Survival of Renal Cancer Cells through Modulation of Apoptosis- and Autophagy-regulating Molecules*

    PubMed Central

    Banerjee, Pallavi; Basu, Aninda; Wegiel, Barbara; Otterbein, Leo E.; Mizumura, Kenji; Gasser, Martin; Waaga-Gasser, Ana Maria; Choi, Augustine M.; Pal, Soumitro

    2012-01-01

    The cytoprotective enzyme heme oxygenase-1 (HO-1) is often overexpressed in different types of cancers and promotes cancer progression. We have recently shown that the Ras-Raf-ERK pathway induces HO-1 to promote survival of renal cancer cells. Here, we examined the possible mechanisms underlying HO-1-mediated cell survival. Considering the growing evidence about the significance of apoptosis and autophagy in cancer, we tried to investigate how HO-1 controls these events to regulate survival of cancer cells. Rapamycin (RAPA) and sorafenib, two commonly used drugs for renal cancer treatment, were found to induce HO-1 expression in renal cancer cells Caki-1 and 786-O; and the apoptotic effect of these drugs was markedly enhanced upon HO-1 knockdown. Overexpression of HO-1 protected the cells from RAPA- and sorafenib-induced apoptosis and also averted drug-mediated inhibition of cell proliferation. HO-1 induced the expression of anti-apoptotic Bcl-xL and decreased the expression of autophagic proteins Beclin-1 and LC3B-II; while knockdown of HO-1 down-regulated Bcl-xL and markedly increased LC3B-II. Moreover, HO-1 promoted the association of Beclin-1 with Bcl-xL and Rubicon, a novel negative regulator of autophagy. Drug-induced dissociation of Beclin-1 from Rubicon and the induction of autophagy were also inhibited by HO-1. Together, our data signify that HO-1 is up-regulated in renal cancer cells as a survival strategy against chemotherapeutic drugs and promotes growth of tumor cells by inhibiting both apoptosis and autophagy. Thus, application of chemotherapeutic drugs along with HO-1 inhibitor may elevate therapeutic efficiency by reducing the cytoprotective effects of HO-1 and by simultaneous induction of both apoptosis and autophagy. PMID:22843690

  17. The OXI1 Kinase Pathway Mediates Piriformospora indica-Induced Growth Promotion in Arabidopsis

    PubMed Central

    Camehl, Iris; Drzewiecki, Corinna; Vadassery, Jyothilakshmi; Shahollari, Bationa; Sherameti, Irena; Forzani, Celine; Munnik, Teun; Hirt, Heribert; Oelmüller, Ralf

    2011-01-01

    Piriformospora indica is an endophytic fungus that colonizes roots of many plant species and promotes growth and resistance to certain plant pathogens. Despite its potential use in agriculture, little is known on the molecular basis of this beneficial plant-fungal interaction. In a genetic screen for plants, which do not show a P. indica- induced growth response, we isolated an Arabidopsis mutant in the OXI1 (Oxidative Signal Inducible1) gene. OXI1 has been characterized as a protein kinase which plays a role in pathogen response and is regulated by H2O2 and PDK1 (3-PHOSPHOINOSITIDE-DEPENDENT PROTEIN KINASE1). A genetic analysis showed that double mutants of the two closely related PDK1.1 and PDK1.2 genes are defective in the growth response to P. indica. While OXI1 and PDK1 gene expression is upregulated in P. indica-colonized roots, defense genes are downregulated, indicating that the fungus suppresses plant defense reactions. PDK1 is activated by phosphatidic acid (PA) and P. indica triggers PA synthesis in Arabidopsis plants. Under beneficial co-cultivation conditions, H2O2 formation is even reduced by the fungus. Importantly, phospholipase D (PLD)α1 or PLDδ mutants, which are impaired in PA synthesis do not show growth promotion in response to fungal infection. These data establish that the P. indica-stimulated growth response is mediated by a pathway consisting of the PLD-PDK1-OXI1 cascade. PMID:21625539

  18. Active form Notch4 promotes the proliferation and differentiation of 3T3-L1 preadipocytes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lai, Peng-Yeh; Tsai, Chong-Bin; Department of Ophthalmology, Chiayi Christian Hospital, Chiayi 600, Taiwan, ROC

    2013-01-18

    Highlights: ► Notch4IC modulates the ERK pathway and cell cycle to promote 3T3-L1 proliferation. ► Notch4IC facilitates 3T3-L1 differentiation by up-regulating proadipogenic genes. ► Notch4IC promotes proliferation during the early stage of 3T3-L1 adipogenesis. ► Notch4IC enhances differentiation during subsequent stages of 3T3-L1 adipogenesis. -- Abstract: Adipose tissue is composed of adipocytes, which differentiate from precursor cells in a process called adipogenesis. Many signal molecules are involved in the transcriptional control of adipogenesis, including the Notch pathway. Previous adipogenic studies of Notch have focused on Notch1 and HES1; however, the role of other Notch receptors in adipogenesis remains unclear. Q-RT-PCRmore » analyses showed that the augmentation of Notch4 expression during the differentiation of 3T3-L1 preadipocytes was comparable to that of Notch1. To elucidate the role of Notch4 in adipogenesis, the human active form Notch4 (N4IC) was transiently transfected into 3T3-L1 cells. The expression of HES1, Hey1, C/EBPδ and PPARγ was up-regulated, and the expression of Pref-1, an adipogenic inhibitor, was down-regulated. To further characterize the effect of N4IC in adipogenesis, stable cells expressing human N4IC were established. The expression of N4IC promoted proliferation and enhanced differentiation of 3T3-L1 cells compared with those of control cells. These data suggest that N4IC promoted proliferation through modulating the ERK pathway and the cell cycle during the early stage of 3T3-L1 adipogenesis and facilitated differentiation through up-regulating adipogenic genes such as C/EBPα, PPARγ, aP2, LPL and HSL during the middle and late stages of 3T3-L1 adipogenesis.« less

  19. Hmo1 directs pre-initiation complex assembly to an appropriate site on its target gene promoters by masking a nucleosome-free region

    PubMed Central

    Kasahara, Koji; Ohyama, Yoshifumi; Kokubo, Tetsuro

    2011-01-01

    Saccharomyces cerevisiae Hmo1 binds to the promoters of ∼70% of ribosomal protein genes (RPGs) at high occupancy, but is observed at lower occupancy on the remaining RPG promoters. In Δhmo1 cells, the transcription start site (TSS) of the Hmo1-enriched RPS5 promoter shifted upstream, while the TSS of the Hmo1-limited RPL10 promoter did not shift. Analyses of chimeric RPS5/RPL10 promoters revealed a region between the RPS5 upstream activating sequence (UAS) and core promoter, termed the intervening region (IVR), responsible for strong Hmo1 binding and an upstream TSS shift in Δhmo1 cells. Chromatin immunoprecipitation analyses showed that the RPS5-IVR resides within a nucleosome-free region and that pre-initiation complex (PIC) assembly occurs at a site between the IVR and a nucleosome overlapping the TSS (+1 nucleosome). The PIC assembly site was shifted upstream in Δhmo1 cells on this promoter, indicating that Hmo1 normally masks the RPS5-IVR to prevent PIC assembly at inappropriate site(s). This novel mechanism ensures accurate transcriptional initiation by delineating the 5′- and 3′-boundaries of the PIC assembly zone. PMID:21288884

  20. Ergot alkaloid transport across ruminant gastric tissues.

    PubMed

    Hill, N S; Thompson, F N; Stuedemann, J A; Rottinghaus, G W; Ju, H J; Dawe, D L; Hiatt, E E

    2001-02-01

    Ergot alkaloids cause fescue toxicosis when livestock graze endophyte-infected tall fescue. It is generally accepted that ergovaline is the toxic component of endophyte-infected tall fescue, but there is no direct evidence to support this hypothesis. The objective of this study was to examine relative and potential transport of ergoline and ergopeptine alkaloids across isolated gastric tissues in vitro. Sheep ruminal and omasal tissues were surgically removed and placed in parabiotic chambers. Equimolar concentrations of lysergic acid, lysergol, ergonovine, ergotamine, and ergocryptine were added to a Kreb's Ringer phosphate (KRP) solution on the mucosal side of the tissue. Tissue was incubated in near-physiological conditions for 240 min. Samples were taken from KRP on the serosal side of the chambers at times 0, 30, 60, 120, 180, and 240 min and analyzed for ergot alkaloids by competitive ELISA. The serosal KRP remaining after incubation was freeze-dried and the alkaloid species quantified by HPLC. The area of ruminal and omasal tissues was measured and the potential transportable alkaloids calculated by multiplying the moles of transported alkaloids per square centimeter of each tissue type by the surface area of the tissue. Studies were conducted to compare alkaloid transport in reticular, ruminal, and omasal tissues and to determine whether transport was active or passive. Ruminal tissue had greater ergot alkaloid transport potential than omasal tissue (85 vs 60 mmol) because of a larger surface area. The ruminal posterior dorsal sac had the greatest potential for alkaloid transport, but the other ruminal tissues were not different from one another. Alkaloid transport was less among reticular tissues than among ruminal tissues. Transport of alkaloids seemed to be an active process. The alkaloids with greatest transport potential were lysergic acid and lysergol. Ergopeptine alkaloids tended to pass across omasal tissues in greater quantities than across ruminal

  1. Acrylamide effects on kinesin-related proteins of the mitotic/meiotic spindle

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sickles, Dale W.; Sperry, Ann O.; Testino, Angie

    The microtubule (MT) motor protein kinesin is a vital component of cells and organs expressing acrylamide (ACR) toxicity. As a mechanism of its potential carcinogenicity, we determined whether kinesins involved in cell division are inhibited by ACR similar to neuronal kinesin [Sickles, D.W., Brady, S.T., Testino, A.R., Friedman, M.A., and Wrenn, R.A. (1996). Direct effect of the neurotoxicant acrylamide on kinesin-based microtubule motility. Journal of Neuroscience Research 46, 7-17.] Kinesin-related genes were isolated from rat testes [Navolanic, P.M., and Sperry, A.O. (2000). Identification of isoforms of a mitotic motor in mammalian spermatogenesis. Biology of Reproduction 62, 1360-1369.], their kinesin-like proteinsmore » expressed in bacteria using recombinant DNA techniques and the effects of ACR, glycidamide (GLY) and propionamide (a non-neurotoxic metabolite) on the function of two of the identified kinesin motors were tested. KIFC5A MT bundling activity, required for mitotic spindle formation, was measured in an MT-binding assay. Both ACR and GLY caused a similar concentration-dependent reduction in the binding of MT; concentrations of 100 {mu}M ACR or GLY reduced its activity by 60%. KRP2 MT disassembling activity was assayed using the quantity of tubulin disassembled from taxol-stabilized MT. Both ACR and GLY inhibited KRP2-induced MT disassembly. GLY was substantially more potent; significant reductions of 60% were achieved by 500 {mu}M, a comparable inhibition by ACR required a 5 mM concentration. Propionamide had no significant effect on either kinesin, except KRP2 at 10 mM. This is the first report of ACR inhibition of a mitotic/meiotic motor protein. ACR (or GLY) inhibition of kinesin may be an alternative mechanism to DNA adduction in the production of cell division defects and potential carcinogenicity. We conclude that ACR may act on multiple kinesin family members and produce toxicities in organs highly dependent on microtubule-based functions.« less

  2. FOXM1 promotes the progression of prostate cancer by regulating PSA gene transcription.

    PubMed

    Liu, Youhong; Liu, Yijun; Yuan, Bowen; Yin, Linglong; Peng, Yuchong; Yu, Xiaohui; Zhou, Weibing; Gong, Zhicheng; Liu, Jianye; He, Leye; Li, Xiong

    2017-03-07

    Androgen/AR is the primary contributor to prostate cancer (PCa) progression by regulating Prostate Specific Antigen (PSA) gene transcription. The disease inevitably evolves to androgen-independent (AI) status. Other mechanisms by which PSA is regulated and develops to AI have not yet been fully determined. FOXM1 is a cell proliferation-specific transcription factor highly expressed in PCa cells compared to non-malignant prostate epithelial cells, suggesting that the aberrant overexpression of FOXM1 contributes to PCa development. In addition to regulating AR gene transcription and cell cycle-regulatory genes, FOXM1 selectively regulates the gene transcription of KLK2 and PSA, typical androgen responsive genes. Screening the potential FOXM1-binding sites by ChIP-PCR, we found that FOXM1 directly binds to the FHK binding motifs in the PSA promoter/enhancer regions. AI C4-2 cells have more FOXM1 binding sites than androgen dependent LNCaP cells. The depletion of FOXM1 by small molecular inhibitors significantly improves the suppression of PSA gene transcription by the anti-AR agent Cadosax. This is the first report showing that FOXM1 promotes PCa progression by regulating PSA gene transcription, particularly in AI PCa cells. The combination of anti-AR agents and FOXM1 inhibitors has the potential to greatly improve therapy for late-stage PCa patients by suppressing PSA levels.

  3. Role of activator protein-1 on the effect of arginine-glycine-aspartic acid containing peptides on transforming growth factor-beta1 promoter activity.

    PubMed

    Ruiz-Torres, M P; Perez-Rivero, G; Diez-Marques, M L; Griera, M; Ortega, R; Rodriguez-Puyol, M; Rodríguez-Puyol, D

    2007-01-01

    While arginine-glycine-aspartic acid-based peptidomimetics have been employed for the treatment of cardiovascular disorders and cancer, their use in other contexts remains to be explored. Arginine-glycine-aspartic acid-serine induces Transforming growth factor-beta1 transcription in human mesangial cells, but the molecular mechanisms involved have not been studied extensively. We explored whether this effect could be due to Activator protein-1 activation and studied the potential pathways involved. Addition of arginine-glycine-aspartic acid-serine promoted Activator protein-1 binding to its cognate sequence within the Transforming growth factor-beta1 promoter as well as c-jun and c-fos protein abundance. Moreover, this effect was suppressed by curcumin, a c-Jun N terminal kinase inhibitor, and was absent when the Activator protein-1 cis-regulatory element was deleted. Activator protein-1 binding was dependent on the activity of integrin linked kinase, as transfection with a dominant negative mutant suppressed both Activator protein-1 binding and c-jun and c-fos protein increment. Integrin linked kinase was, in turn, dependent on Phosphoinositol-3 kinase activity. Arginine-glycine-aspartic acid-serine stimulated Phosphoinositol-3 kinase activity, and Transforming growth factor-beta1 promoter activation was abrogated by the use of Phosphoinositol-3 kinase specific inhibitors. In summary, we propose that arginine-glycine-aspartic acid-serine activates Integrin linked kinase via the Phosphoinositol-3 kinase pathway and this leads to activation of c-jun and c-fos and increased Activator protein-1 binding and Transforming growth factor-beta1 promoter activity. These data may contribute to understand the molecular mechanisms involved in the cellular actions of arginine-glycine-aspartic acid-related peptides and enhance their relevance as these products evolve into clinical therapeutic use.

  4. Promoter analysis reveals cis-regulatory motifs associated with the expression of the WRKY transcription factor CrWRKY1 in Catharanthus roseus.

    PubMed

    Yang, Zhirong; Patra, Barunava; Li, Runzhi; Pattanaik, Sitakanta; Yuan, Ling

    2013-12-01

    WRKY transcription factors (TFs) are emerging as an important group of regulators of plant secondary metabolism. However, the cis-regulatory elements associated with their regulation have not been well characterized. We have previously demonstrated that CrWRKY1, a member of subgroup III of the WRKY TF family, regulates biosynthesis of terpenoid indole alkaloids in the ornamental and medicinal plant, Catharanthus roseus. Here, we report the isolation and functional characterization of the CrWRKY1 promoter. In silico analysis of the promoter sequence reveals the presence of several potential TF binding motifs, indicating the involvement of additional TFs in the regulation of the TIA pathway. The CrWRKY1 promoter can drive the expression of a β-glucuronidase (GUS) reporter gene in native (C. roseus protoplasts and transgenic hairy roots) and heterologous (transgenic tobacco seedlings) systems. Analysis of 5'- or 3'-end deletions indicates that the sequence located between positions -140 to -93 bp and -3 to +113 bp, relative to the transcription start site, is critical for promoter activity. Mutation analysis shows that two overlapping as-1 elements and a CT-rich motif contribute significantly to promoter activity. The CrWRKY1 promoter is induced in response to methyl jasmonate (MJ) treatment and the promoter region between -230 and -93 bp contains a putative MJ-responsive element. The CrWRKY1 promoter can potentially be used as a tool to isolate novel TFs involved in the regulation of the TIA pathway.

  5. The Solanum tuberosum KST1 partial promoter as a tool for guard cell expression in multiple plant species.

    PubMed

    Kelly, Gilor; Lugassi, Nitsan; Belausov, Eduard; Wolf, Dalia; Khamaisi, Belal; Brandsma, Danja; Kottapalli, Jayaram; Fidel, Lena; Ben-Zvi, Batsheva; Egbaria, Aiman; Acheampong, Atiako Kwame; Zheng, Chuanlin; Or, Etti; Distelfeld, Assaf; David-Schwartz, Rakefet; Carmi, Nir; Granot, David

    2017-05-17

    To date, guard cell promoters have been examined in only a few species, primarily annual dicots. A partial segment of the potato (Solanum tuberosum) KST1 promoter (KST1 partial promoter, KST1ppro) has previously been shown to confer guard cell expression in potato, tomato (Solanum lycopersicum), citrus [Troyer citrange (C. sinensis×Poncirus trifoliata)], and Arabidopsis (Arabidopsis thaliana). Here, we describe an extensive analysis of the expression pattern of KST1ppro in eight (previously reported, as well as new) species from five different angiosperm families, including the Solanaceae and the Cucurbitaceae, Arabidopsis, the monocot barley (Hordeum vulgare), and two perennial species: grapevine (Vitis vinifera) and citrus. Using confocal imaging and three-dimensional movies, we demonstrate that KST1ppro drives guard cell expression in all of these species, making it the first dicot-originated guard cell promoter shown to be active in a monocot and the first promoter reported to confer guard cell expression in barley and cucumber (Cucumis sativus). The results presented here indicate that KST1ppro can be used to drive constitutive guard cell expression in monocots and dicots and in both annual and perennial plants. In addition, we show that the KST1ppro is active in guard cells shortly after the symmetric division of the guard mother cell and generates stable expression in mature guard cells. This allows us to follow the spatial and temporal distribution of stomata in cotyledons and true leaves. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  6. Loss of CX3CR1 increases accumulation of inflammatory monocytes and promotes gliomagenesis

    PubMed Central

    Feng, Xi; Chen, Zhihong; Heinzmann, David; Rasmussen, Rikke Darling; Alvarez-Garcia, Virginia; Kim, Yeonghwan; Wang, Bingcheng; Tamagno, Ilaria; Zhou, Hao; Li, Xiaoxia; Kettenmann, Helmut; Ransohoff, Richard M.; Hambardzumyan, Dolores

    2015-01-01

    The most abundant populations of non-neoplastic cells in the glioblastoma (GBM) microenvironment are resident microglia, macrophages and infiltrating monocytes from the blood circulation. The mechanisms by which monocytes infiltrate into GBM, their fate following infiltration, and their role in GBM growth are not known. Here we tested the hypothesis that loss of the fractalkine receptor CX3CR1 in microglia and monocytes would affect gliomagenesis. Deletion of Cx3cr1 from the microenvironment resulted in increased tumor incidence and shorter survival times in glioma-bearing mice. Loss of Cx3cr1 did not affect accumulation of microglia/macrophages in peri-tumoral areas, but instead indirectly promoted the trafficking of CD11b+CD45hiCX3CR1lowLy-6ChiLy-6G−F4/80−/low circulating inflammatory monocytes into the CNS, resulting in their increased accumulation in the perivascular area. Cx3cr1-deficient microglia/macrophages and monocytes demonstrated upregulation of IL1β expression that was inversely proportional to Cx3cr1 gene dosage. The Proneural subgroup of the TCGA GBM patient dataset with high IL1β expression showed shorter survival compared to patients with low IL1β. IL1β promoted tumor growth and increased the cancer stem cell phenotype in murine and human Proneural glioma stem cells (GSCs). IL1β activated the p38 MAPK signaling pathway and expression of monocyte chemoattractant protein (MCP-1/CCL2) by tumor cells. Loss of Cx3cr1 in microglia in a monocyte-free environment had no impact on tumor growth and did not alter microglial migration. These data suggest that enhancing signaling to CX3CR1 or inhibiting IL1β signaling in intra-tumoral macrophages can be considered as potential strategies to decrease the tumor-promoting effects of monocytes in Proneural GBM. PMID:25987130

  7. SOX10 Regulates Expression of the SH3-Domain Kinase Binding Protein 1 (Sh3kbp1) locus in Schwann Cells via an Alternative Promoter

    PubMed Central

    Hodonsky, Chani J.; Kleinbrink, Erica L.; Charney, Kira N.; Prasad, Megana; Bessling, Seneca L.; Jones, Erin A.; Srinivasan, Rajini; Svaren, John; McCallion, Andrew S.; Antonellis, Anthony

    2011-01-01

    The transcription factor SOX10 has essential roles in neural crest-derived cell populations, including myelinating Schwann cells—specialized glial cells responsible for ensheathing axons in the peripheral nervous system. Importantly, SOX10 directly regulates the expression of genes essential for proper myelin function. To date, only a handful of SOX10 target loci have been characterized in Schwann cells. Addressing this lack of knowledge will provide a better understanding of Schwann cell biology and candidate loci for relevant diseases such as demyelinating peripheral neuropathies. We have identified a highly-conserved SOX10 binding site within an alternative promoter at the SH3-domain kinase binding protein 1 (Sh3kbp1) locus. The genomic segment identified at Sh3kbp1 binds to SOX10 and displays strong promoter activity in Schwann cells in vitro and in vivo. Mutation of the SOX10 binding site ablates promoter activity, and ectopic expression of SOX10 in SOX10-negative cells promotes the expression of endogenous Sh3kbp1. Combined, these data reveal Sh3kbp1 as a novel target of SOX10 and raise important questions regarding the function of SH3KBP1 isoforms in Schwann cells. PMID:22037207

  8. An Expedient Regio- and Diastereoselective Synthesis of Hybrid Frameworks with Embedded Spiro[9,10]dihydroanthracene [9,3']-pyrrolidine and Spiro[oxindole-3,2'-pyrrolidine] Motifs via an Ionic Liquid-Mediated Multicomponent Reaction.

    PubMed

    Arumugam, Natarajan; Almansour, Abdulrahman I; Kumar, Raju Suresh; Menéndez, J Carlos; Sultan, Mujeeb A; Karama, Usama; Ghabbour, Hazem A; Fun, Hoong-Kun

    2015-09-03

    A series of hitherto unreported anthracene-embedded dispirooxindoles has been synthesized via a one-pot three-component 1,3-dipolar cycloaddition reaction of an azomethine ylide, generated in situ from the reaction of isatin and sarcosine to 10-benzylideneanthracen-9(10H)-one as a dipolarophile in 1-butyl-3-methylimidazolium bromide([bmim]Br), an ionic liquid. This reaction proceeded regio- and diastereoselectively, in good to excellent yields.

  9. Mesenchymal stem cells promote pancreatic adenocarcinoma cells invasion by transforming growth factor-β1 induced epithelial-mesenchymal transition.

    PubMed

    Zhou, Hai-Sen; Su, Xiao-Fang; Fu, Xing-Li; Wu, Guo-Zhong; Luo, Kun-Lun; Fang, Zheng; Yu, Feng; Liu, Hong; Hu, Hong-Juan; Chen, Liu-Sheng; Cai, Bing; Tian, Zhi-Qiang

    2016-07-05

    Mesenchymal stem cells (MSCs) could be ideal delivery vehicles for antitumor biological agents in pancreatic adenocarcinoma (PA). While the role of MSCs in tumor growth is elusive. Inflammation is an important feature of PA. In this study, we reported that MSCs pre-stimulated with the combination of TNF-α and IFN-γ promote PA cells invasion. The invasion of PA cell lines were evaluate by wound healing assay and transwell assay in vitro and liver metastasis in nude mice. We observed MSCs pre-stimulated with the combination of TNF-α and IFN-γ promoted PA cells invasion in vitro and in vivo. Consistent with MSCs promoting PA cells invasion, PA cells were found undergo epithelial-mesenchymal transition (EMT). We demonstrated that MSCs pre-stimulated with both of TNF-α and IFN-γ provoked expression transforming growth factor-β1 (TGF-β1). MSCs promoting EMT-mediated PA cells invasion could be reversed by short interfering RNA of TGF-β1. Our results suggest that MSCs could promote PA cells invasion in inflammation microenvironment and should be cautious as delivery vehicles in molecular target therapy.

  10. Osteoblast-secreted WISP-1 promotes adherence of prostate cancer cells to bone via the VCAM-1/integrin α4β1 system.

    PubMed

    Chang, An-Chen; Chen, Po-Chun; Lin, Yu-Feng; Su, Chen-Ming; Liu, Ju-Fang; Lin, Tien-Huang; Chuang, Show-Mei; Tang, Chih-Hsin

    2018-07-10

    Bone metastasis is a frequent occurrence in prostate cancer (PCa) that is associated with severe complications such as fracture, bone pain and hypercalcemia. The cross-talk between metastatic cancer cells and bone is critical to the development and progression of bone metastases. In our previous data, we have described how the involvement of the Wnt-induced secreted protein-1/vascular cell adhesion molecule-1 (WISP-1/VCAM-1) system in this tumor-bone interaction contributes to human PCa cell motility. In this study, we found that WISP-1 regulates bone mineralization by inducing bone morphogenetic protein-2 (BMP2), BMP4 and osteopontin (OPN) expression in osteoblasts. We also found that WISP-1 inhibited RANKL-dependent osteoclastogenesis. Moreover, osteoblast-derived WISP-1 enhanced VCAM-1 expression in PCa cells and subsequently promoted the adherence of cancer cells to osteoblasts. Furthermore, endothelin-1 (ET-1) expression in PCa cells was regulated by osteoblast-derived WISP-1, which promoted integrin α4β1 expression in osteoblasts via the MAPK pathway. Pretreatment of PCa cells with VCAM-1 antibody or osteoblasts with integrin α4β1 antibody attenuated the adherence of PCa cells to osteoblasts, suggesting that integrin α4β1 serves as a ligand that captures VCAM-1 + metastatic tumor cells adhering to osteoblasts. Our findings reveal that osteoblast-derived WISP-1 plays a key role in regulating the adhesion of PCa cells to osteoblasts via the VCAM-1/integrin α4β1 system. Osteoblast-derived WISP-1 is a promising target for the prevention and inhibition of PCa-bone interaction. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Activated mTORC1 promotes long-term cone survival in retinitis pigmentosa mice

    PubMed Central

    Venkatesh, Aditya; Ma, Shan; Le, Yun Z.; Hall, Michael N.; Rüegg, Markus A.; Punzo, Claudio

    2015-01-01

    Retinitis pigmentosa (RP) is an inherited photoreceptor degenerative disorder that results in blindness. The disease is often caused by mutations in genes that are specific to rod photoreceptors; however, blindness results from the secondary loss of cones by a still unknown mechanism. Here, we demonstrated that the mammalian target of rapamycin complex 1 (mTORC1) is required to slow the progression of cone death during disease and that constitutive activation of mTORC1 in cones is sufficient to maintain cone function and promote long-term cone survival. Activation of mTORC1 in cones enhanced glucose uptake, retention, and utilization, leading to increased levels of the key metabolite NADPH. Moreover, cone death was delayed in the absence of the NADPH-sensitive cell death protease caspase 2, supporting the contribution of reduced NADPH in promoting cone death. Constitutive activation of mTORC1 preserved cones in 2 mouse models of RP, suggesting that the secondary loss of cones is caused mainly by metabolic deficits and is independent of a specific rod-associated mutation. Together, the results of this study address a longstanding question in the field and suggest that activating mTORC1 in cones has therapeutic potential to prolong vision in RP. PMID:25798619

  12. TIMP3 Promoter Methylation Represents an Epigenetic Marker of BRCA1ness Breast Cancer Tumours.

    PubMed

    Maleva Kostovska, Ivana; Jakimovska, Milena; Popovska-Jankovic, Katerina; Kubelka-Sabit, Katerina; Karagjozov, Mitko; Plaseska-Karanfilska, Dijana

    2018-03-09

    Tumours presenting BRCAness profile behave more aggressively and are more invasive as a consequence of their complex genetic and epigenetic alterations, caused by impaired fidelity of the DNA repair processes. Methylation of promoter CpG islands represents an alternative mechanism to inactivate DNA repair and tumour suppressor genes. In our study, we analyzed the frequency of methylation changes of 24 tumour suppressor genes and explored their association with BRCAness profile. BRCA1ness profile and aberrant methylation were studied in 233 fresh frozen breast tumour tissues by Multiplex Ligation-dependent Probe Amplification (MLPA) and Methylation Specific (MS)-MLPA methods, respectively. Our analyses revealed that 12.4% of the breast cancer (BC) patients had tumours with a BRCA1ness profile. TIMP3 showed significantly higher (p = 5.8х10 -5 ) methylation frequency in tumours with BRCA1ness, while methylation of APC, GSTP1 and RASSF1 promoters was negatively associated with BRCA1ness (р = 0.0017, р = 0.007 and р = 0.046, respectively). TIMP3 methylation was also associated with triple negative (TN) BC. Furthermore, TN tumours showing BRCA1ness showed stronger association with TIMP3 methylation (p = 0.0008) in comparison to TN tumours without BRCA1ness (p = 0.009). In conclusion, we confirmed that TIMP3 methylation is a marker for TN tumours and furthermore we showed for the first time that TIMP3 promoter methylation is an epigenetic marker of BRCA1ness tumours.

  13. BRCA1 and FancJ cooperatively promote interstrand crosslinker induced centrosome amplification through the activation of polo-like kinase 1

    PubMed Central

    Zou, Jianqiu; Zhang, Deli; Qin, Guang; Chen, Xiangming; Wang, Hongmin; Zhang, Dong

    2014-01-01

    DNA damage response (DDR) and the centrosome cycle are 2 of the most critical cellular processes affecting the genome stability in animal cells. Yet the cross-talks between DDR and the centrosome are poorly understood. Here we showed that deficiency of the breast cancer 1, early onset gene (BRCA1) induces centrosome amplification in non-stressed cells as previously reported while attenuating DNA damage-induced centrosome amplification (DDICA) in cells experiencing prolonged genotoxic stress. Mechanistically, the function of BRCA1 in promoting DDICA is through binding and recruiting polo-like kinase 1 (PLK1) to the centrosome. In a recent study, we showed that FancJ also suppresses centrosome amplification in non-stressed cells while promoting DDICA in both hydroxyurea and mitomycin C treated cells. FancJ is a key component of the BRCA1 B-complex. Here, we further demonstrated that, in coordination with BRCA1, FancJ promotes DDICA by recruiting both BRCA1 and PLK1 to the centrosome in the DNA damaged cells. Thus, we have uncovered a novel role of BRCA1 and FancJ in the regulation of DDICA. Dysregulation of DDR or centrosome cycle leads to aneuploidy, which is frequently seen in both solid and hematological cancers. BRCA1 and FancJ are known tumor suppressors and have well-recognized functions in DNA damage checkpoint and DNA repair. Together with our recent findings, we demonstrated here that BRCA1 and FancJ also play an important role in centrosome cycle especially in DDICA. DDICA is thought to be an alternative fail-safe mechanism to prevent cells experiencing severe DNA damage from becoming carcinogenic. Therefore, BRCA1 and FancJ are potential liaisons linking early DDR with the DDICA. We propose that together with their functions in DDR, the role of BRCA1 and FancJ in the activation of DDICA is also crucial for their tumor suppression functions in vivo. PMID:25483079

  14. A conserved intronic U1 snRNP-binding sequence promotes trans-splicing in Drosophila

    PubMed Central

    Gao, Jun-Li; Fan, Yu-Jie; Wang, Xiu-Ye; Zhang, Yu; Pu, Jia; Li, Liang; Shao, Wei; Zhan, Shuai; Hao, Jianjiang

    2015-01-01

    Unlike typical cis-splicing, trans-splicing joins exons from two separate transcripts to produce chimeric mRNA and has been detected in most eukaryotes. Trans-splicing in trypanosomes and nematodes has been characterized as a spliced leader RNA-facilitated reaction; in contrast, its mechanism in higher eukaryotes remains unclear. Here we investigate mod(mdg4), a classic trans-spliced gene in Drosophila, and report that two critical RNA sequences in the middle of the last 5′ intron, TSA and TSB, promote trans-splicing of mod(mdg4). In TSA, a 13-nucleotide (nt) core motif is conserved across Drosophila species and is essential and sufficient for trans-splicing, which binds U1 small nuclear RNP (snRNP) through strong base-pairing with U1 snRNA. In TSB, a conserved secondary structure acts as an enhancer. Deletions of TSA and TSB using the CRISPR/Cas9 system result in developmental defects in flies. Although it is not clear how the 5′ intron finds the 3′ introns, compensatory changes in U1 snRNA rescue trans-splicing of TSA mutants, demonstrating that U1 recruitment is critical to promote trans-splicing in vivo. Furthermore, TSA core-like motifs are found in many other trans-spliced Drosophila genes, including lola. These findings represent a novel mechanism of trans-splicing, in which RNA motifs in the 5′ intron are sufficient to bring separate transcripts into close proximity to promote trans-splicing. PMID:25838544

  15. Identification of the minimum pharmacophore of lipid-phosphatidylserine (PS) binding peptide-peptoid hybrid PPS1D1.

    PubMed

    Singh, Jaspal; Shukla, Satya Prakash; Desai, Tanvi J; Udugamasooriya, D Gomika

    2016-09-15

    We previously reported a unique peptide-peptoid hybrid, PPS1 that specifically recognizes lipid-phosphatidylserine (PS) and a few other negatively charged phospholipids, but not neutral phospholipids, on the cell membrane. The dimeric version of PPS1, i.e., PPS1D1 triggers strong cancer cell cytotoxicity and has been validated in lung cancer models both in vitro and in vivo. Given that PS and other negatively charged phospholipids are abundant in almost all tumor microenvironments, PPS1D1 is an attractive drug lead that can be developed into a globally applicable anti-cancer agent. Therefore, it is extremely important to identify the minimum pharmacophore of PPS1D1. In this study, we have synthesized alanine/sarcosine derivatives as well as truncated derivatives of PPS1D1. We performed ELISA-like competitive binding assay to evaluate the PS-recognition potential and standard MTS cell viability assay on HCC4017 lung cancer cells to validate the cell cytotoxicity effects of these derivatives. Our studies indicate that positively charged residues at the second and third positions, as well as four hydrophobic residues at the fifth through eighth positions, are imperative for the binding and activity of PPS1D1. Methionine at the first position was not essential, whereas the positively charged Nlys at the fourth position was minimally needed, as two derivatives that were synthesized replacing this residue were almost as active as PPS1D1. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Tumour-derived Interleukin 35 promotes pancreatic ductal adenocarcinoma cell extravasation and metastasis by inducing ICAM1 expression

    PubMed Central

    Huang, Chongbiao; Li, Na; Li, Zengxun; Chang, Antao; Chen, Yanan; Zhao, Tiansuo; Li, Yang; Wang, Xiuchao; Zhang, Wei; Wang, Zhimin; Luo, Lin; Shi, Jingjing; Yang, Shengyu; Ren, He; Hao, Jihui

    2017-01-01

    Interleukin 35 (IL-35) is a novel member of the IL-12 family, consisting of an EBV-induced gene 3 (EBI3) subunit and a P35 subunit. IL-35 is an immune-suppressive cytokine mainly produced by regulatory T cells. However, the role of IL-35 in cancer metastasis and progression is not well understood. Here we demonstrate that IL-35 is overexpressed in human pancreatic ductal adenocarcinoma (PDAC) tissues, and that IL-35 overexpression is associated with poor prognosis in PDAC patients. IL-35 has critical roles in PDAC cell extravasation and metastasis by facilitating the adhesion to endothelial cells and transendothelial extravasation. Mechanistically, IL-35 promotes ICAM1 overexpression through a GP130-STAT1 signalling pathway, which facilitates endothelial adhesion and transendothelial migration via an ICAM1–fibrinogen–ICAM1 bridge. In an orthotopic xenograft model, IL-35 promotes spontaneous pancreatic cancer metastasis in an ICAM1-dependent manner. Together, our results indicate additional functions of IL-35 in promoting PDAC metastasis through mediating ICAM1 expression. PMID:28102193

  17. Methods for promoting wound healing and muscle regeneration with the cell signaling protein nell1

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Culiat, Cymbeline T.

    The present invention provides methods for promoting wound healing and treating muscle atrophy in a mammal in need. The method comprises administering to the mammal a Nell1 protein or a Nell1 nucleic acid molecule.

  18. Methods for promoting wound healing and muscle regeneration with the cell signaling protein Nell1

    DOEpatents

    Culiat, Cymbeline T

    2014-11-04

    The present invention provides methods for promoting wound healing and treating muscle atrophy in a mammal in need. The method comprises administering to the mammal a Nell1 protein or a Nell1 nucleic acid molecule.

  19. Methods for promoting wound healing and muscle regeneration with the cell signaling protein Nell1

    DOEpatents

    Culiat, Cymbeline T [Oak Ridge, TN

    2011-03-22

    The present invention provides methods for promoting wound healing and treating muscle atrophy in a mammal in need. The method comprises administering to the mammal a Nell1 protein or a Nell1 nucleic acid molecule.

  20. Derlin-1 promotes ubiquitylation and degradation of the epithelial Na+ channel, ENaC.

    PubMed

    You, Hui; Ge, Yamei; Zhang, Jian; Cao, Yizhi; Xing, Jing; Su, Dongming; Huang, Yujie; Li, Min; Qu, Shen; Sun, Fei; Liang, Xiubin

    2017-03-15

    Ubiquitylation of the epithelial Na + channel (ENaC) plays a critical role in cellular functions, including transmembrane transport of Na + , Na + and water balance, and blood pressure stabilization. Published studies have suggested that ENaC subunits are targets of ER-related degradation (ERAD) in yeast systems. However, the molecular mechanism underlying proteasome-mediated degradation of ENaC subunits remains to be established. Derlin-1, an E3 ligase mediator, links recognized target proteins to ubiquitin-mediated proteasomal degradation in the cytosol. In the present study, we found that derlin-1 suppressed the expression of ENaC at the protein level and that the subunit α-ENaC (also known as SCNN1A) physically interacted with derlin-1 at the membrane-anchored domains or the loop regions, and that derlin-1 initiated α-ENaC retrotranslocation. In addition, HUWE1, an endoplasmic reticulum (ER)-resident E3 ubiquitin ligase, was recruited and promoted K11-linked polyubiquitylation of α-ENaC and, hence, formation of an α-ENaC ubiquitin-mediated degradation complex. These findings suggest that derlin-1 promotes ENaC ubiquitylation and enhances ENaC ubiquitin- mediated proteasome degradation. The derlin-1 pathway therefore may represent a significant early checkpoint in the recognition and degradation of ENaC in mammalian cells. © 2017. Published by The Company of Biologists Ltd.

  1. Primary Tr1 cells from metastatic melanoma eliminate tumor-promoting macrophages through granzyme B- and perforin-dependent mechanisms.

    PubMed

    Yan, Hongxia; Zhang, Ping; Kong, Xue; Hou, Xianglian; Zhao, Li; Li, Tianhang; Yuan, Xiaozhou; Fu, Hongjun

    2017-04-01

    In malignant melanoma, tumor-associated macrophages play multiple roles in promoting tumor growth, such as inducing the transformation of melanocytes under ultraviolet irradiation, increasing angiogenesis in melanomas, and suppressing antitumor immunity. Because granzyme B- and perforin-expressing Tr1 cells could specifically eliminate antigen-presenting cells of myeloid origin, we examined whether Tr1 cells in melanoma could eliminate tumor-promoting macrophages and how the interaction between Tr1 cells and macrophages could affect the growth of melanoma cells. Tr1 cells were characterized by high interleukin 10 secretion and low Foxp3 expression and were enriched in the CD4 + CD49b + LAG-3 + T-cell fraction. Macrophages derived from peripheral blood monocytes in the presence of modified melanoma-conditioned media demonstrated tumor-promoting capacity, exemplified by improving the proliferation of cocultured A375 malignant melanoma cells. But when primary Tr1 cells were present in the macrophage-A375 coculture, the growth of A375 cells was abrogated. The conventional CD25 + Treg cells, however, were unable to inhibit macrophage-mediated increase in tumor cell growth. Further analyses showed that Tr1 cells did not directly eliminate A375 cells, but mediated the killing of tumor-promoting macrophages through the secretion of granzyme B and perforin. The tumor-infiltrating interleukin 10 + Foxp3 - CD4 + T cells expressed very low levels of granzyme B and perforin, possibly suggested the downregulation of Tr1 cytotoxic capacity in melanoma tumors. Together, these data demonstrated an antitumor function of Tr1 cells through the elimination of tumor-promoting macrophages, which was not shared by conventional Tregs.

  2. Thioredoxin-1 promotes colorectal cancer invasion and metastasis through crosstalk with S100P.

    PubMed

    Lin, Feiyan; Zhang, Peili; Zuo, Zhigui; Wang, Fule; Bi, Ruichun; Shang, Wenjing; Wu, Aihua; Ye, Ju; Li, Shaotang; Sun, Xuecheng; Wu, Jianbo; Jiang, Lei

    2017-08-10

    Thioredoxin-1 (Trx-1) is a small redox-regulating protein, which plays an important role in several cellular functions. Despite recent advances in understanding the biology of Trx-1, the role of Trx-1 and its underlying signaling mechanism in colorectal cancer (CRC) metastasis have not been extensively studied. In this study, we observed that Trx-1 expression is increased in CRC tissues compared to the paired non-cancerous tissues and is significantly correlated with clinical staging, lymph node metastasis and poor survival. Overexpression of Trx-1 enhanced CRC cell invasion and metastasis in vitro and in vivo. Conversely, suppression of Trx-1 expression decreased cell invasion and metastasis in vitro and in vivo. Moreover, Trx-1 activates S100P gene transcription. S100P, in turn, promotes Trx-1 expression and nuclear localization by upregulating p-ERK1/2 and downregulating TXNIP expression. Our finding provides new insight into the mechanism of Trx-1/S100P axis in the promotion of CRC metastasis, and suggests that the Trx-1/S100P axis and their related signaling pathways could be novel targets for the treatment of metastatic CRC. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. DEPS-1 promotes P-granule assembly and RNA interference in C. elegans germ cells

    PubMed Central

    Spike, Caroline A.; Bader, Jason; Reinke, Valerie; Strome, Susan

    2008-01-01

    P granules are germ-cell-specific cytoplasmic structures containing RNA and protein, and required for proper germ cell development in C. elegans. PGL-1 and GLH-1 were previously identified as critical components of P granules. We have identified a new P-granule-associated protein, DEPS-1, the loss of which disrupts P-granule structure and function. DEPS-1 is required for the proper localization of PGL-1 to P granules, the accumulation of glh-1 mRNA and protein, and germ cell proliferation and fertility at elevated temperatures. In addition, DEPS-1 is required for RNA interference (RNAi) of germline-expressed genes, possibly because DEPS-1 promotes the accumulation of RDE-4, a dsRNA-binding protein required for RNAi. A genome wide analysis of gene expression in deps-1 mutant germ lines identified additional targets of DEPS-1 regulation, many of which are also regulated by the RNAi factor RDE-3. Our studies suggest that DEPS-1 is a key component of the P-granule assembly pathway and that its roles include promoting accumulation of some mRNAs, such as glh-1 and rde-4, and reducing accumulation of other mRNAs, perhaps by collaborating with RDE-3 to generate endogenous short interfering RNAs (endo-siRNAs). PMID:18234720

  4. DEPS-1 promotes P-granule assembly and RNA interference in C. elegans germ cells.

    PubMed

    Spike, Caroline A; Bader, Jason; Reinke, Valerie; Strome, Susan

    2008-03-01

    P granules are germ-cell-specific cytoplasmic structures containing RNA and protein, and required for proper germ cell development in C. elegans. PGL-1 and GLH-1 were previously identified as critical components of P granules. We have identified a new P-granule-associated protein, DEPS-1, the loss of which disrupts P-granule structure and function. DEPS-1 is required for the proper localization of PGL-1 to P granules, the accumulation of glh-1 mRNA and protein, and germ cell proliferation and fertility at elevated temperatures. In addition, DEPS-1 is required for RNA interference (RNAi) of germline-expressed genes, possibly because DEPS-1 promotes the accumulation of RDE-4, a dsRNA-binding protein required for RNAi. A genome wide analysis of gene expression in deps-1 mutant germ lines identified additional targets of DEPS-1 regulation, many of which are also regulated by the RNAi factor RDE-3. Our studies suggest that DEPS-1 is a key component of the P-granule assembly pathway and that its roles include promoting accumulation of some mRNAs, such as glh-1 and rde-4, and reducing accumulation of other mRNAs, perhaps by collaborating with RDE-3 to generate endogenous short interfering RNAs (endo-siRNAs).

  5. STIM1 Overexpression Promotes Colorectal Cancer Progression, Cell Motility and COX-2 Expression

    PubMed Central

    Wang, Jaw-Yuan; Sun, Jianwei; Huang, Ming-Yii; Wang, Yu-Shiuan; Hou, Ming-Feng; Sun, Yan; He, Huifang; Krishna, Niveditha; Chiu, Siou-Jin; Lin, Shengchen; Yang, Shengyu; Chang, Wei-Chiao

    2014-01-01

    Tumor metastasis is the major cause of death among cancer patients, with more than 90% of cancer-related death attributable to the spreading of metastatic cells to secondary organs. Store-operated Ca2+ entry (SOCE) is the predominant Ca2+ entry mechanism in most cancer cells, and STIM1 is the endoplasmic reticulum (ER) Ca2+ sensor for store-operated channels (SOC). Here we reported that the STIM1 was overexpressed in colorectal cancer (CRC) patients. STIM1 overexpression in CRC was significantly associated with tumor size, depth of invasion, lymphnode metastasis status and serum levels of carcinoembryonic antigen. Furthermore, ectopic expression of STIM1 promoted CRC cell motility, while depletion of STIM1 with shRNA inhibited CRC cell migration. Our data further suggested that STIM1 promoted CRC cell migration through increasing the expression of cyclooxygenase-2 (COX-2) and production of prostaglandin E2 (PGE2). Importantly, ectopically expressed COX-2 or exogenous PGE2 were able to rescue migration defect in STIM1 knockdown CRC cells, and inhibition of COX-2 with ibuprofen and indomethacin abrogated STIM1-mediated CRC cell motility. In short, our data provided clinicopathological significance for STIM1 and store-operated Ca2+ entry in CRC progression, and implicated a role for COX-2 in STIM1-mediated CRC metastasis. Our studies also suggested a new approach to inhibit STIM1-mediated metastasis with COX-2 inhibitors. PMID:25381814

  6. miR-543 promotes gastric cancer cell proliferation by targeting SIRT1

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, Juan; Dong, Guoying; Wang, Bo

    SIRT1, a class III histone deacetylase, exerts inhibitory effects on tumorigenesis and is downregulated in gastric cancer. However, the role of microRNAs in the regulation of SIRT1 in gastric cancer is still largely unknown. Here, we identified miR-543 as a predicted upstream regulator of SIRT1 using 3 different bioinformatics databases. Mimics of miR-543 significantly inhibited the expression of SIRT1, whereas an inhibitor of miR-543 increased SIRT1 expression. MiR-543 directly targeted the 3′-UTR of SIRT1, and both of the two binding sites contributed to the inhibitory effects. In gastric epithelium-derived cell lines, miR-543 promoted cell proliferation and cell cycle progression, andmore » overexpression of SIRT1 rescued the above effects of miR-543. The inhibitory effects of miR-543 on SIRT1 were also validated using clinical gastric cancer samples. Moreover, we found that miR-543 expression was positively associated with tumor size, clinical grade, TNM stage and lymph node metastasis in gastric cancer patients. Our results identify a new regulatory mechanism of miR-543 on SIRT1 expression in gastric cancer, and raise the possibility that the miR-543/SIRT1 pathway may serve as a potential target for the treatment of gastric cancer. - Highlights: • SIRT1 is a novel target of miR-543. • miR-543 promotes gastric cancer cell proliferation and cell cycle progression by targeting SIRT1. • miR-543 is upregulated in GC and positively associated with tumor size, clinical grade, TNM stage and lymph node metastasis. • miR-543 is negatively correlated with SIRT1 expression in gastric cancer tissues.« less

  7. Resolvin D1 prevents smoking-induced emphysema and promotes lung tissue regeneration.

    PubMed

    Kim, Kang-Hyun; Park, Tai Sun; Kim, You-Sun; Lee, Jae Seung; Oh, Yeon-Mok; Lee, Sang-Do; Lee, Sei Won

    2016-01-01

    Emphysema is an irreversible disease that is characterized by destruction of lung tissue as a result of inflammation caused by smoking. Resolvin D1 (RvD1), derived from docosahexaenoic acid, is a novel lipid that resolves inflammation. The present study tested whether RvD1 prevents smoking-induced emphysema and promotes lung tissue regeneration. C57BL/6 mice, 8 weeks of age, were randomly divided into four groups: control, RvD1 only, smoking only, and smoking with RvD1 administration. Four different protocols were used to induce emphysema and administer RvD1: mice were exposed to smoking for 4 weeks with poly(I:C) or to smoking only for 24 weeks, and RvD1 was injected within the smoking exposure period to prevent regeneration or after completion of smoking exposure to assess regeneration. The mean linear intercept and inflammation scores were measured in the lung tissue, and inflammatory cells and cytokines were measured in the bronchoalveolar lavage fluid. Measurements of mean linear intercept showed that RvD1 significantly attenuated smoking-induced lung destruction in all emphysema models. RvD1 also reduced smoking-induced inflammatory cell infiltration, which causes the structural derangements observed in emphysema. In the 4-week prevention model, RvD1 reduced the smoking-induced increase in eosinophils and interleukin-6 in the bronchoalveolar lavage fluid. In the 24-week prevention model, RvD1 also reduced the increased neutrophils and total cell counts induced by smoking. RvD1 attenuated smoking-induced emphysema in vivo by reducing inflammation and promoting tissue regeneration. This result suggests that RvD1 may be useful in the prevention and treatment of emphysema.

  8. PD-1 and PD-L1 Up-regulation Promotes T-cell Apoptosis in Gastric Adenocarcinoma.

    PubMed

    Chiu, Ying-Ming; Tsai, Chung-Lin; Kao, Jung-Ta; Hsieh, Chin-Tung; Shieh, Dong-Chen; Lee, Yi-Ju; Tsay, Gregory J; Cheng, Ken-Sheng; Wu, Yi-Ying

    2018-04-01

    The programmed death 1 (PD-1) receptor and its ligand (PD-L1) play pivotal roles in regulating host immune responses. However, the inhibitory effects of this pathway on the function of tumor infiltrating T lymphocytes in gastric adenocarcinoma patients are not well-defined. We characterized the expression of PD-1 and PD-L1 in peripheral blood and tumor infiltrating cells and analyzed the association between PD-1/PD-L1 expression and disease progression in a cohort of 60 patients with Helicobacter pylori infection, including 18 with gastric adenocarcinoma, 23 with gastritis, and 19 asymptomatic controls. Relative to controls, the expression of PD-1 on peripheral blood and tumor infiltrating T cells increased with disease progression. In vitro, T cells induced PD-L1 expression on primary gastric adenocarcinoma epithelial cells in an IFN-γ-dependent manner, which in turn promoted T cells apoptosis. Blocking of PD-L1 reversed this effect. This study provides evidence for a new therapeutic target in gastric adenocarcinoma patients. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  9. Long non-coding RNA SNHG1 predicts a poor prognosis and promotes colon cancer tumorigenesis.

    PubMed

    Yang, Huan; Wang, Shuang; Kang, Yu-Jun; Wang, Chuan; Xu, Yongzhu; Zhang, Yi; Jiang, Zheng

    2018-05-02

    Colon cancer is the main cause of cancer mortality worldwide. Its poor prognosis is mainly ascribed to high recurrence rates. Identifying novel prognostic biomarkers and therapeutic key points for management is crucial and important. Long non-coding RNAs (lncRNAs) are a class of RNAs, which have various roles in carcinogenicity and molecular mechanisms. The lncRNA small nucleolar RNA host gene 1 (SNHG1) contributes to the promotion of tumor development, however, the connections between SNHG1 and colon cancer are still unclear. The aim of the present study was to investigate the clinical significance, the biological functions, and the potential mechanism of SNHG1 in colon cancer. In the present study, we referred to the Oncomine database and used RT-qPCR to determine that SNHG1 expression was significantly higher both in colon cancer tissues and cancerous cell lines than in normal samples. Cell functional experiments were performed after knockdown of SNHG1, including Cell Counting Kit-8 assay, colony formation assay, Transwell® assay, and flow cytometric analyses of cell apoptosis, which suggested that SNHG1 stimulated colon cancer cell proliferation, promoted cell invasion and migration, and inhibited apoptosis. Immunohistochemical staining and western blotting experiments revealed that in colon cancer cells with SNHG1 knockdown, β-catenin, c-Myc and cyclin D1 protein levels were decreased, while E-cadherin was increased, which suggested that SNHG1 promoted colon cancer cell proliferation, migration and invasion through the Wnt/β-catenin signaling pathway. Our results indicated that SNHG1 and its interrelated components may be future therapeutic targets of carcinoma of the colon.

  10. NADPH oxidase-mediated redox signaling promotes oxidative stress resistance and longevity through memo-1 in C. elegans

    PubMed Central

    Ewald, Collin Yvès; Hourihan, John M; Bland, Monet S; Obieglo, Carolin; Katic, Iskra; Moronetti Mazzeo, Lorenza E; Alcedo, Joy; Blackwell, T Keith; Hynes, Nancy E

    2017-01-01

    Transient increases in mitochondrially-derived reactive oxygen species (ROS) activate an adaptive stress response to promote longevity. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidases produce ROS locally in response to various stimuli, and thereby regulate many cellular processes, but their role in aging remains unexplored. Here, we identified the C. elegans orthologue of mammalian mediator of ErbB2-driven cell motility, MEMO-1, as a protein that inhibits BLI-3/NADPH oxidase. MEMO-1 is complexed with RHO-1/RhoA/GTPase and loss of memo-1 results in an enhanced interaction of RHO-1 with BLI-3/NADPH oxidase, thereby stimulating ROS production that signal via p38 MAP kinase to the transcription factor SKN-1/NRF1,2,3 to promote stress resistance and longevity. Either loss of memo-1 or increasing BLI-3/NADPH oxidase activity by overexpression is sufficient to increase lifespan. Together, these findings demonstrate that NADPH oxidase-induced redox signaling initiates a transcriptional response that protects the cell and organism, and can promote both stress resistance and longevity. DOI: http://dx.doi.org/10.7554/eLife.19493.001 PMID:28085666

  11. Erythrocyte plasma membrane-bound ERK1/2 activation promotes ICAM-4-mediated sickle red cell adhesion to endothelium.

    PubMed

    Zennadi, Rahima; Whalen, Erin J; Soderblom, Erik J; Alexander, Susan C; Thompson, J Will; Dubois, Laura G; Moseley, M Arthur; Telen, Marilyn J

    2012-02-02

    The core pathology of sickle cell disease (SCD) starts with the erythrocyte (RBC). Aberration in MAPK/ERK1/2 signaling, which can regulate cell adhesion, occurs in diverse pathologies. Because RBCs contain abundant ERK1/2, we predicted that ERK1/2 is functional in sickle (SS) RBCs and promotes adherence, a hallmark of SCD. ERK1/2 remained active in SS but not normal RBCs. β(2)-adrenergic receptor stimulation by epinephrine can enhance ERK1/2 activity only in SS RBCs via PKA- and tyrosine kinase p72(syk)-dependent pathways. ERK signaling is implicated in RBC ICAM-4 phosphorylation, promoting SS RBC adhesion to the endothelium. SS RBC adhesion and phosphorylation of both ERK and ICAM-4 all decreased with continued cell exposure to epinephrine, implying that activation of ICAM-4-mediated SS RBC adhesion is temporally associated with ERK1/2 activation. Furthermore, recombinant ERK2 phosphorylated α- and β-adducins and dematin at the ERK consensus motif. Cytoskeletal protein 4.1 also showed dynamic phosphorylation but not at the ERK consensus motif. These results demonstrate that ERK activation induces phosphorylation of cytoskeletal proteins and the adhesion molecule ICAM-4, promoting SS RBC adhesion to the endothelium. Thus, blocking RBC ERK1/2 activation, such as that promoted by catecholamine stress hormones, could ameliorate SCD pathophysiology.

  12. PLOD2 regulated by transcription factor FOXA1 promotes metastasis in NSCLC

    PubMed Central

    Du, Hongzhi; Chen, Yulong; Hou, Xiaoying; Huang, Yue; Wei, Xiaohui; Yu, Xiaowen; Feng, Shuyun; Wu, Yao; Zhan, Meixiao; Shi, Xin; Lin, Sensen; Lu, Ligong; Yuan, Shengtao; Sun, Li

    2017-01-01

    In multiple types of tumors, fibrotic collagen is regarded as the 'highway' for cancer cell migration, which is mainly modified by lysyl hydroxylase 2 (PLOD2). The previous findings have demonstrated that the expression of PLOD2 was regulated by multiple factors, including HIF-1α, TGF-β and microRNA-26a/b. Although PLOD2 was confirmed to be related to poor prognosis in lung adenocarcinoma, the regulatory mechanism and function of PLOD2 in human lung adenocarcinoma is poorly understood. On the other hand, upregulation or hyperactivation of epidermal growth factor receptor is considered as a prognostic marker in many cancers, especially in non-small-cell lung cancer (NSCLC). In this study, we found that PLOD2 was elevated in NSCLC specimens and positively links to NSCLC poor prognosis. Gain- and loss-of-function studies and orthotopic implantation metastasis model pinpointed that PLOD2 promotes NSCLC metastasis directly by enhancing migration and indirectly by inducing collagen reorganization. In addition, we revealed that PLOD2 was regulated by PI3K/AKT-FOXA1 axis. The transcription factor FOXA1 directly bound to the PLOD2 promoter, and turned on PLOD2 transcription. In summary, our findings revealed a regulatory mechanism of NSCLC metastasis through EGFR-PI3K/AKT-FOXA1-PLOD2 pathway, and provided PLOD2 as a therapeutic target for NSCLC treatment. PMID:29072684

  13. The 15-LO-1/15-HETE system promotes angiogenesis by upregulating VEGF in ischemic brains.

    PubMed

    Chen, Li; Zhu, Yan-Mei; Li, Yu-Nong; Li, Peng-Yan; Wang, Di; Liu, Yu; Qu, You-Yang; Zhu, Da-Ling; Zhu, Yu-Lan

    2017-09-01

    Angiogenesis promotes neurobehavioral recovery after cerebral ischemic stroke. 15(S)-hydroxyeicosatetraenoic acid (15-HETE) is one of the major metabolites of arachidonic acid by 15-lipoxygenase (15-LO) and stimulates the production of vascular endothelial growth factor (VEGF), thus, inducing autocrine-mediated angiogenesis. The present study aimed to investigate the role of 15-LO/15-HETE system on VEGF expression and angiogenesis in brain ischemia. Rat cerebral arterial vascular endothelial cells were used to set up a cell injury model of oxygen-glucose deprivation and reoxygenation (OGD/R), mimicking a condition of brain ischemia. A mouse model of middle cerebral artery occlusion (MCAO) was established. Oxygen-glucose deprivation increased cellular expression of 15-LO-1 and VEGF. Transfection of 15-LO-1 siRNA depleted cells of 15-LO-1, and sequentially induced downregulation of VEGF expression; while, incubation of 15-HETE increased the expression of VEGF. Incubation of 15-HETE attenuated the reduction in cell viability induced by oxygen-glucose deprivation, and promoted cell migration, while transfection of 15-LO-1 siRNA showed an opposite effect. In animal experiments, the density of microvessels in hypoxic regions of brains was significantly increased after MCAO, while intracerebroventricular delivery of 15-LO-1 siRNA significantly reduced the density of microvessels, and downregulates VEGF expression. The results indicate that the 15-LO-1/15-HETE system promotes angiogenesis in ischemic brains by upregulation of VEGF, representing a potential target for improving neurobehavioral recovery after cerebral ischemic stroke.

  14. Activation of GLP-1 Receptor Promotes Bone Marrow Stromal Cell Osteogenic Differentiation through β-Catenin

    PubMed Central

    Meng, Jingru; Ma, Xue; Wang, Ning; Jia, Min; Bi, Long; Wang, Yunying; Li, Mingkai; Zhang, Huinan; Xue, Xiaoyan; Hou, Zheng; Zhou, Ying; Yu, Zhibin; He, Gonghao; Luo, Xiaoxing

    2016-01-01

    Summary Glucagon-like peptide 1 (GLP-1) plays an important role in regulating bone remodeling, and GLP-1 receptor agonist shows a positive relationship with osteoblast activity. However, GLP-1 receptor is not found in osteoblast, and the mechanism of GLP-1 receptor agonist on regulating bone remodeling is unclear. Here, we show that the GLP-1 receptor agonist exendin-4 (Ex-4) promoted bone formation and increased bone mass and quality in a rat unloading-induced bone loss model. These functions were accompanied by an increase in osteoblast number and serum bone formation markers, while the adipocyte number was decreased. Furthermore, GLP-1 receptor was detected in bone marrow stromal cells (BMSCs), but not in osteoblast. Activation of GLP-1 receptor by Ex-4 promoted the osteogenic differentiation and inhibited BMSC adipogenic differentiation through regulating PKA/β-catenin and PKA/PI3K/AKT/GSK3β signaling. These findings reveal that GLP-1 receptor regulates BMSC osteogenic differentiation and provide a molecular basis for therapeutic potential of GLP-1 against osteoporosis. PMID:26947974

  15. Sphingosine-1-phosphate promotes erythrocyte glycolysis and oxygen release for adaptation to high-altitude hypoxia

    PubMed Central

    Sun, Kaiqi; Zhang, Yujin; D'Alessandro, Angelo; Nemkov, Travis; Song, Anren; Wu, Hongyu; Liu, Hong; Adebiyi, Morayo; Huang, Aji; Wen, Yuan E.; Bogdanov, Mikhail V.; Vila, Alejandro; O'Brien, John; Kellems, Rodney E.; Dowhan, William; Subudhi, Andrew W.; Jameson-Van Houten, Sonja; Julian, Colleen G.; Lovering, Andrew T.; Safo, Martin; Hansen, Kirk C.; Roach, Robert C.; Xia, Yang

    2016-01-01

    Sphingosine-1-phosphate (S1P) is a bioactive signalling lipid highly enriched in mature erythrocytes, with unknown functions pertaining to erythrocyte physiology. Here by employing nonbiased high-throughput metabolomic profiling, we show that erythrocyte S1P levels rapidly increase in 21 healthy lowland volunteers at 5,260 m altitude on day 1 and continue increasing to 16 days with concurrently elevated erythrocyte sphingonisne kinase 1 (Sphk1) activity and haemoglobin (Hb) oxygen (O2) release capacity. Mouse genetic studies show that elevated erythrocyte Sphk1-induced S1P protects against tissue hypoxia by inducing O2 release. Mechanistically, we show that intracellular S1P promotes deoxygenated Hb anchoring to the membrane, enhances the release of membrane-bound glycolytic enzymes to the cytosol, induces glycolysis and thus the production of 2,3-bisphosphoglycerate (2,3-BPG), an erythrocyte-specific glycolytic intermediate, which facilitates O2 release. Altogether, we reveal S1P as an intracellular hypoxia-responsive biolipid promoting erythrocyte glycolysis, O2 delivery and thus new therapeutic opportunities to counteract tissue hypoxia. PMID:27417539

  16. The regulation of the Z- and G-box containing promoters by light signaling components, SPA1 and MYC2, in Arabidopsis.

    PubMed

    Gangappa, Sreeramaiah N; Maurya, Jay P; Yadav, Vandana; Chattopadhyay, Sudip

    2013-01-01

    Although many transcription factors and regulatory proteins have been identified and functionally characterized in light signaling pathways, photoperception to transcription remains largely fragmented. The Z-box is one of the LREs (Light responsive elements) that plays important role in the regulation of transcription during light-controlled Arabidopsis seedling development. The involvement of photoreceptors in the modulation of the activity of the Z-box containing promoters has been demonstrated. However, the role of downstream signaling components such as SPA1 and MYC2/ZBF1, which are functionally interrelated, remains unknown. In this study, we have investigated the regulation of the Z-box containing synthetic and native promoters by SPA1 and MYC2 by using stable transgenic lines. Our studies suggest that SPA1 negatively regulates the expression of CAB1 native promoter. MYC2 negatively regulates the activity of Z- and/or G-box containing synthetic as well as native promoters irrespective of light quality. Moreover, MYC2 negatively regulates the expression of Z/G-NOS101-GUS even in the darkness. Furthermore, analyses of tissue specific expression in adult plants suggest that MYC2 strongly regulates the activity of Z- and G-box containing promoters specifically in leaves and stems. In roots, whereas MYC2 positively regulates the activity of the Z-box containing synthetic promoter, it does not seem to control the activity of the G-box containing promoters. Taken together, these results provide insights into SPA1- and MYC2-mediated transcriptional regulation of the Z- and G-box containing promoters in light signaling pathways.

  17. NLR Nod1 signaling promotes survival of BCR-engaged mature B cells through up-regulated Nod1 as a positive outcome

    PubMed Central

    Asano, Masanao; Li, Yue-Sheng; Núñez, Gabriel

    2017-01-01

    Although B cell development requires expression of the B cell antigen receptor (BCR), it remains unclear whether engagement of self-antigen provides a positive impact for most B cells. Here, we show that BCR engagement by self-ligand during development in vivo results in up-regulation of the Nod-like receptor member Nod1, which recognizes the products of intestinal commensal bacteria. In anti-thymocyte/Thy-1 autoreactive BCR knock-in mice lacking self–Thy-1 ligand, immunoglobulin light chain editing occurred, generating B cells with up-regulated Nod1, including follicular and marginal zone B cells with natural autoreactivity. This BCR editing with increased Nod1 resulted in preferential survival. In normal adult mice, most mature B cells are enriched for Nod1 up-regulated cells, and signaling through Nod1 promotes competitive survival of mature B cells. These findings demonstrate a role for microbial products in promoting survival of mature B cells through up-regulated Nod1, providing a positive effect of BCR engagement on development of most B cells. PMID:28878001

  18. Selective Inhibition of the Human tie-1 Promoter with Triplex-Forming Oligonucleotides Targeted to Ets Binding Sites

    PubMed Central

    Hewett, Peter W; Daft, Emma L; Laughton, Charles A; Ahmad, Shakil; Ahmed, Asif; Murray, J Clifford

    2006-01-01

    The Tie receptors (Tie-1 and Tie-2/Tek) are essential for angiogenesis and vascular remodeling/integrity. Tie receptors are up-regulated in tumor-associated endothelium, and their inhibition disrupts angiogenesis and can prevent tumor growth as a consequence. To investigate the potential of anti-gene approaches to inhibit tie gene expression for anti-angiogenic therapy, we have examined triple-helical (triplex) DNA formation at 2 tandem Ets transcription factor binding motifs (designated E-1 and E-2) in the human tie-1 promoter. Various tie-1 promoter deletion/mutation luciferase reporter constructs were generated and transfected into endothelial cells to examine the relative activities of E-1 and E-2. The binding of antiparallel and parallel (control) purine motif oligonucleotides (21–22 bp) targeted to E-1 and E-2 was assessed by plasmid DNA fragment binding and electrophoretic mobility shift assays. Triplex-forming oligonucleotides were incubated with tie-1 reporter constructs and transfected into endothelial cells to determine their activity. The Ets binding motifs in the E-1 sequence were essential for human tie-1 promoter activity in endothelial cells, whereas the deletion of E-2 had no effect. Antiparallel purine motif oligonucleotides targeted at E-1 or E-2 selectively formed strong triplex DNA (Kd ~10−7 M) at 37 °C. Transfection of tie-1 reporter constructs with triplex DNA at E-1, but not E-2, specifically inhibited tie-1 promoter activity by up to 75% compared with control oligonucleotides in endothelial cells. As similar multiple Ets binding sites are important for the regulation of several endothelial-restricted genes, this approach may have broad therapeutic potential for cancer and other pathologies involving endothelial proliferation/dysfunction. PMID:16838069

  19. Selective inhibition of the human tie-1 promoter with triplex-forming oligonucleotides targeted to Ets binding sites.

    PubMed

    Hewett, Peter W; Daft, Emma L; Laughton, Charles A; Ahmad, Shakil; Ahmed, Asif; Murray, J Clifford

    2006-01-01

    The Tie receptors (Tie-1 and Tie-2/Tek) are essential for angiogenesis and vascular remodeling/integrity. Tie receptors are up-regulated in tumor-associated endothelium, and their inhibition disrupts angiogenesis and can prevent tumor growth as a consequence. To investigate the potential of anti-gene approaches to inhibit tie gene expression for anti-angiogenic therapy, we have examined triple-helical (triplex) DNA formation at 2 tandem Ets transcription factor binding motifs (designated E-1 and E-2) in the human tie-1 promoter. Various tie-1 promoter deletion/mutation luciferase reporter constructs were generated and transfected into endothelial cells to examine the relative activities of E-1 and E-2. The binding of antiparallel and parallel (control) purine motif oligonucleotides (21-22 bp) targeted to E-1 and E-2 was assessed by plasmid DNA fragment binding and electrophoretic mobility shift assays. Triplex-forming oligonucleotides were incubated with tie-1 reporter constructs and transfected into endothelial cells to determine their activity. The Ets binding motifs in the E-1 sequence were essential for human tie-1 promoter activity in endothelial cells, whereas the deletion of E-2 had no effect. Antiparallel purine motif oligonucleotides targeted at E-1 or E-2 selectively formed strong triplex DNA (K(d) approximately 10(-7) M) at 37 degrees C. Transfection of tie-1 reporter constructs with triplex DNA at E-1, but not E-2, specifically inhibited tie-1 promoter activity by up to 75% compared with control oligonucleotides in endothelial cells. As similar multiple Ets binding sites are important for the regulation of several endothelial-restricted genes, this approach may have broad therapeutic potential for cancer and other pathologies involving endothelial proliferation/dysfunction.

  20. Progesterone and HMOX-1 promote fetal growth by CD8+ T cell modulation

    PubMed Central

    Solano, María Emilia; Kowal, Mirka Katharina; O’Rourke, Greta Eugenia; Horst, Andrea Kristina; Modest, Kathrin; Plösch, Torsten; Barikbin, Roja; Remus, Chressen Catharina; Berger, Robert G.; Jago, Caitlin; Ho, Hoang; Sass, Gabriele; Parker, Victoria J.; Lydon, John P.; DeMayo, Francesco J.; Hecher, Kurt; Karimi, Khalil; Arck, Petra Clara

    2015-01-01

    Intrauterine growth restriction (IUGR) affects up to 10% of pregnancies in Western societies. IUGR is a strong predictor of reduced short-term neonatal survival and impairs long-term health in children. Placental insufficiency is often associated with IUGR; however, the molecular mechanisms involved in the pathogenesis of placental insufficiency and IUGR are largely unknown. Here, we developed a mouse model of fetal-growth restriction and placental insufficiency that is induced by a midgestational stress challenge. Compared with control animals, pregnant dams subjected to gestational stress exhibited reduced progesterone levels and placental heme oxygenase 1 (Hmox1) expression and increased methylation at distinct regions of the placental Hmox1 promoter. These stress-triggered changes were accompanied by an altered CD8+ T cell response, as evidenced by a reduction of tolerogenic CD8+CD122+ T cells and an increase of cytotoxic CD8+ T cells. Using progesterone receptor– or Hmox1-deficient mice, we identified progesterone as an upstream modulator of placental Hmox1 expression. Supplementation of progesterone or depletion of CD8+ T cells revealed that progesterone suppresses CD8+ T cell cytotoxicity, whereas the generation of CD8+CD122+ T cells is supported by Hmox1 and ameliorates fetal-growth restriction in Hmox1 deficiency. These observations in mice could promote the identification of pregnancies at risk for IUGR and the generation of clinical interventional strategies. PMID:25774501

  1. UDP-glucose:glycoprotein glucosyltransferase (UGGT1) promotes substrate solubility in the endoplasmic reticulum

    PubMed Central

    Ferris, Sean P.; Jaber, Nikita S.; Molinari, Maurizio; Arvan, Peter; Kaufman, Randal J.

    2013-01-01

    Protein folding in the endoplasmic reticulum (ER) is error prone, and ER quality control (ERQC) processes ensure that only correctly folded proteins are exported from the ER. Glycoproteins can be retained in the ER by ERQC, and this retention contributes to multiple human diseases, termed ER storage diseases. UDP-glucose:glycoprotein glucosyltransferase (UGGT1) acts as a central component of glycoprotein ERQC, monoglucosylating deglucosylated N-glycans of incompletely folded glycoproteins and promoting subsequent reassociation with the lectin-like chaperones calreticulin and calnexin. The extent to which UGGT1 influences glycoprotein folding, however, has only been investigated for a few selected substrates. Using mouse embryonic fibroblasts lacking UGGT1 or those with UGGT1 complementation, we investigated the effect of monoglucosylation on the soluble/insoluble distribution of two misfolded α1-antitrypsin (AAT) variants responsible for AAT deficiency disease: null Hong Kong (NHK) and Z allele. Whereas substrate solubility increases directly with the number of N-linked glycosylation sites, our results indicate that additional solubility is conferred by UGGT1 enzymatic activity. Monoglucosylation-dependent solubility decreases both BiP association with NHK and unfolded protein response activation, and the solubility increase is blocked in cells deficient for calreticulin. These results suggest that UGGT1-dependent monoglucosylation of N-linked glycoproteins promotes substrate solubility in the ER. PMID:23864712

  2. Recruitment of CREB1 and Histone Deacetylase 2 (HDAC2) to the Mouse Ltbp-1 Promoter Regulates its Constitutive Expression in a Dioxin Receptor-dependent Manner

    PubMed Central

    Gomez-Duran, Aurea; Ballestar, Esteban; Carvajal-Gonzalez, Jose M.; Marlowe, Jennifer L.; Puga, Alvaro; Esteller, Manel; Fernandez-Salguero, Pedro M.

    2010-01-01

    Latent TGFβ-binding protein 1 (LTBP-1) is a key regulator of TGFβ targeting and activation in the extracellular matrix. LTBP-1 is recognized as a major docking molecule to localize, and possibly to activate, TGFβ in the extracellular matrix. Despite this relevant function, the molecular mechanisms regulating Ltbp-1 transcription remain largely unknown. Previous results from our laboratory revealed that mouse embryonic fibroblasts (MEF) lacking dioxin receptor (AhR) had increased Ltbp-1 mRNA expression and elevated TGFβ activity, suggesting that AhR repressed Ltbp-1 transcription. Here, we have cloned the mouse Ltbp-1 gene promoter and analysed its mechanism of transcriptional repression by AhR. Reporter gene assays, AhR over-expression and site-directed mutagenesis showed that basal Ltbp-1 transcription is AhR-dependent. Chromatin immunoprecipitation (ChIP) and RNA interference (RNAi) revealed that AhR regulates Ltbp-1 transcription by a mechanism involving recruitment of co-activators such as CREB1 and co-repressors such as HDAC2 to the Ltbp-1 promoter. In AhR-expressing (AhR+/+) MEF cells, the recruitment of HDAC1, 2 and 4 correlated with decreased K8H4 acetylation and impaired binding of pCREBSer133 to the Ltbp-1 promoter, likely maintaining a constitutive repressed state. AhR−/− MEF cells had the opposite pattern of HDACs and pCREB1Ser133 binding to Ltbp-1 promoter, and therefore, over-expressed Ltbp-1 mRNA. In agreement, siRNA for HDAC2 increased Ltbp-1 expression and K8H4 acetylation in AhR+/+ but not in AhR−/− MEF cells. We suggest that HDAC2 binding keeps Ltbp-1 promoter repressed in AhR+/+ MEF cells, whereas in AhR-null MEF cells the absence of HDAC2 and the binding of pCREBSer133 allow Ltbp-1 transcription. Thus, epigenetics can contribute to constitutive Ltbp-1 repression by a mechanism requiring AhR activity. PMID:18508077

  3. Resolvin D1 promotes corneal epithelial wound healing and restoration of mechanical sensation in diabetic mice.

    PubMed

    Zhang, Zhenzhen; Hu, Xiaoli; Qi, Xia; Di, Guohu; Zhang, Yangyang; Wang, Qian; Zhou, Qingjun

    2018-01-01

    To investigate the effect and mechanism of proresolving lipid mediator resolvin D1 (RvD1) on the corneal epithelium and the restoration of mechanical sensation in diabetic mice. Type 1 diabetes was induced in mice with intraperitoneal streptozocin injections. The healthy and diabetic mice underwent removal of the central corneal epithelium, and then 100 ng/ml RvD1 or its formyl peptide receptor 2 (FPR2) antagonist WRW4 was used to treat the diabetic mice. Regeneration of the corneal epithelium and nerves was observed with sodium fluorescein staining and whole-mount anti-β3-tubulin fluorescence staining. The inflammatory response level was measured with hematoxylin and eosin staining (inflammatory cell infiltration), enzyme-linked immunosorbent assay (tumor necrosis factor alpha and interleukin-1 beta content), myeloperoxidase activity, and fluorescence staining (macrophage content). The reactive oxygen species (ROS) and glutathione (GSH) levels were examined with incubation with fluorescent probes, and oxidative stress-related protein expression levels were evaluated with fluorescence staining and western blotting. Topical application of RvD1 promoted regeneration of the corneal epithelium in diabetic mice, accompanied by the reactivation of signaling and inflammation resolution related to regeneration of the epithelium. Furthermore, RvD1 directly attenuated the accumulation of ROS and nicotinamide adenine dinucleotide phosphate oxidase 2/4 expression, while RvD1 enhanced GSH synthesis and reactivated the Nrf2-ARE signaling pathway that was impaired in the corneal epithelium in the diabetic mice. More interestingly, topical application of RvD1 promoted regeneration of corneal nerves and completely restored impaired mechanical sensitivity of the cornea in diabetic mice. In addition, the promotion of corneal epithelial wound healing by RvD1 in diabetic mice was abolished by its FPR2 antagonist WRW4. Topical application of RvD1 promotes corneal epithelial wound

  4. Anti-DKK1 antibody promotes bone fracture healing through activation of β-catenin signaling

    PubMed Central

    Jin, Hongting; Wang, Baoli; Li, Jia; Xie, Wanqing; Mao, Qiang; Li, Shan; Dong, Fuqiang; Sun, Yan; Ke, Hua-Zhu; Babij, Philip; Tong, Peijian; Chen, Di

    2015-01-01

    In this study we investigated if Wnt/β-catenin signaling in mesenchymal progenitor cells plays a role in bone fracture repair and if DKK1-Ab promotes fracture healing through activation of β-catenin signaling. Unilateral open transverse tibial fractures were created in CD1 mice and in β-cateninPrx1ER conditional knockout (KO) and Cre-negative control mice (C57BL/6 background). Bone fracture callus tissues were collected and analyzed by radiography, micro-CT (μCT), histology, biomechanical testing and gene expression analysis. The results demonstrated that treatment with DKK1-Ab promoted bone callus formation and increased mechanical strength during the fracture healing processinCD1 mice. DKK1-Ab enhanced fracture repair by activation of endochondral ossification. The normal rate of bone repair was delayed when the β-catenin gene was conditionally deleted in mesenchymal progenitor cells during the early stages of fracture healing. DKK1-Ab appeared to act through β-catenin signaling to enhance bone repair since the beneficial effect of DKK1-Ab was abrogated in β-cateninPrx1ER conditional KO mice. Further understanding of the signaling mechanism of DKK1-Ab in bone formation and bone regeneration may facilitate the clinical translation of this anabolic agent into therapeutic intervention. PMID:25263522

  5. Thrombospondin-1 modified bone marrow mesenchymal stem cells (BMSCs) promote neurite outgrowth and functional recovery in rats with spinal cord injury

    PubMed Central

    Pu, Yujie; Meng, Ke; Gu, Chuanlong; Wang, Linlin; Zhang, Xiaoming

    2017-01-01

    Stem cell therapies are currently gaining momentum in the treatment of spinal cord injury (SCI). However, unsatisfied intrinsic neurite growth capacity constitutes significant obstacles for injured spinal cord repair and ultimately results in neurological dysfunction. The present study assessed the efficacy of thrombospondin-1 (TSP-1), a neurite outgrowth-promoting molecule, modified bone marrow mesenchymal stem cells (BMSCs) on promoting neurite outgrowth in vitro and in vivo of Oxygen–Glucose Deprivation (OGD) treated motor neurons and SCI rat models. The present results demonstrated that the treatment of BMSCs+TSP-1 could promote the neurite length, neuronal survival, and functional recovery after SCI. Additionally, TSP-1 could activate transforming growth factor-β1 (TGF-β1) then induced the smad2 phosphorylation, and expedited the expression of GAP-43 to promote neurite outgrowth. The present study for the first time demonstrated that BMSCs+TSP-1 could promote neurite outgrowth and functional recovery after SCI partly through the TGF-β1/p-Samd2 pathway. The study provided a novel encouraging evidence for the potential treatment of BMSCs modification with TSP-1 in patients with SCI. PMID:29221205

  6. Heme controls ferroportin1 (FPN1) transcription involving Bach1, Nrf2 and a MARE/ARE sequence motif at position -7007 of the FPN1 promoter.

    PubMed

    Marro, Samuele; Chiabrando, Deborah; Messana, Erika; Stolte, Jens; Turco, Emilia; Tolosano, Emanuela; Muckenthaler, Martina U

    2010-08-01

    Macrophages of the reticuloendothelial system play a key role in recycling iron from hemoglobin of senescent or damaged erythrocytes. Heme oxygenase 1 degrades the heme moiety and releases inorganic iron that is stored in ferritin or exported to the plasma via the iron export protein ferroportin. In the plasma, iron binds to transferrin and is made available for de novo red cell synthesis. The aim of this study was to gain insight into the regulatory mechanisms that control the transcriptional response of iron export protein ferroportin to hemoglobin in macrophages. Iron export protein ferroportin mRNA expression was analyzed in RAW264.7 mouse macrophages in response to hemoglobin, heme, ferric ammonium citrate or protoporphyrin treatment or to siRNA mediated knockdown or overexpression of Btb And Cnc Homology 1 or nuclear accumulation of Nuclear Factor Erythroid 2-like. Iron export protein ferroportin promoter activity was analyzed using reporter constructs that contain specific truncations of the iron export protein ferroportin promoter or mutations in a newly identified MARE/ARE element. We show that iron export protein ferroportin is transcriptionally co-regulated with heme oxygenase 1 by heme, a degradation product of hemoglobin. The protoporphyrin ring of heme is sufficient to increase iron export protein ferroportin transcriptional activity while the iron released from the heme moiety controls iron export protein ferroportin translation involving the IRE in the 5'untranslated region. Transcription of iron export protein ferroportin is inhibited by Btb and Cnc Homology 1 and activated by Nuclear Factor Erythroid 2-like involving a MARE/ARE element located at position -7007/-7016 of the iron export protein ferroportin promoter. This finding suggests that heme controls a macrophage iron recycling regulon involving Btb and Cnc Homology 1 and Nuclear Factor Erythroid 2-like to assure the coordinated degradation of heme by heme oxygenase 1, iron storage and

  7. IQGAP1 promotes CXCR4 chemokine receptor function and trafficking via EEA-1+ endosomes

    PubMed Central

    Bamidele, Adebowale O.; Kremer, Kimberly N.; Hirsova, Petra; Clift, Ian C.; Gores, Gregory J.; Billadeau, Daniel D.

    2015-01-01

    IQ motif–containing GTPase-activating protein 1 (IQGAP1) is a cytoskeleton-interacting scaffold protein. CXCR4 is a chemokine receptor that binds stromal cell–derived factor-1 (SDF-1; also known as CXCL12). Both IQGAP1 and CXCR4 are overexpressed in cancer cell types, yet it was unclear whether these molecules functionally interact. Here, we show that depleting IQGAP1 in Jurkat T leukemic cells reduced CXCR4 expression, disrupted trafficking of endocytosed CXCR4 via EEA-1+ endosomes, and decreased efficiency of CXCR4 recycling. SDF-1–induced cell migration and activation of extracellular signal-regulated kinases 1 and 2 (ERK) MAPK were strongly inhibited, even when forced overexpression restored CXCR4 levels. Similar results were seen in KMBC and HEK293 cells. Exploring the mechanism, we found that SDF-1 treatment induced IQGAP1 binding to α-tubulin and localization to CXCR4-containing endosomes and that CXCR4-containing EEA-1+ endosomes were abnormally located distal from the microtubule (MT)-organizing center (MTOC) in IQGAP1-deficient cells. Thus, IQGAP1 critically mediates CXCR4 cell surface expression and signaling, evidently by regulating EEA-1+ endosome interactions with MTs during CXCR4 trafficking and recycling. IQGAP1 may similarly promote CXCR4 functions in other cancer cell types. PMID:26195666

  8. The Bro1-Domain Protein, EGO-2, Promotes Notch Signaling in Caenorhabditis elegans

    PubMed Central

    Liu, Ying; Maine, Eleanor M.

    2007-01-01

    In Caenorhabditis elegans, as in other animals, Notch-type signaling mediates numerous inductive events during development. The mechanism of Notch-type signaling involves proteolytic cleavage of the receptor and subsequent transport of the receptor intracellular domain to the nucleus, where it acts as a transcriptional regulator. Notch-type signaling activity is modulated by post-translational modifications and endocytosis of ligand and receptor. We previously identified the ego-2 (enhancer of glp-1) gene as a positive regulator of germline proliferation that interacts genetically with the GLP-1/Notch signaling pathway in the germline. Here, we show that ego-2 positively regulates signaling in various tissues via both GLP-1 and the second C. elegans Notch-type receptor, LIN-12. ego-2 activity also promotes aspects of development not known to require GLP-1 or LIN-12. The EGO-2 protein contains a Bro1 domain, which is known in other systems to localize to certain endosomal compartments. EGO-2 activity in the soma promotes GLP-1 signaling in the germline, consistent with a role for EGO-2 in production of active ligand. Another C. elegans Bro1-domain protein, ALX-1, is known to interact physically with LIN-12/Notch. We document a complex phenotypic interaction between ego-2 and alx-1, consistent with their relationship being antagonistic with respect to some developmental processes and agonistic with respect to others. PMID:17603118

  9. Generation of recombinant European bat lyssavirus type 1 and inter-genotypic compatibility of lyssavirus genotype 1 and 5 antigenome promoters.

    PubMed

    Orbanz, Jeannette; Finke, Stefan

    2010-10-01

    Bat lyssaviruses (Fam. Rhabdoviridae) represent a source for the infection of terrestial mammals and the development of rabies disease. Molecular differences in the replication of bat and non-bat lyssaviruses and their contribution to pathogenicity, however, are unknown. One reason for this is the lack of reverse genetics systems for bat-restricted lyssaviruses. To investigate bat lyssavirus replication and host adaptation, we developed a reverse genetics system for European bat lyssavirus type 1 (EBLV-1; genotype 5). This was achieved by co-transfection of HEK-293T cells with a full-length EBLV-1 genome cDNA and expression plasmids for EBLV-1 proteins, resulting in recombinant EBLV-1 (rEBLV-1). Replication of rEBLV-1 was comparable to that of parental virus, showing that rEBLV-1 is a valid tool to investigate EBLV-1 replication functions. In a first approach, we tested whether the terminal promoter sequences of EBLV-1 are genotype-specific. Although genotype 1 (rabies virus) minigenomes were successfully amplified by EBLV-1 helper virus, in the context of the complete virus, only the antigenome promoter (AGP) sequence of EBLV-1 was replaceable, as indicated by comparable replication of rEBLV-1 and the chimeric virus. These analyses demonstrate that the terminal AGPs of genotype 1 and genotype 5 lyssaviruses are compatible with those of the heterologous genotype.

  10. Human FGF1 promoter is active in ependymal cells and dopaminergic neurons in the brains of F1B-GFP transgenic mice.

    PubMed

    Chen, Mei-Shu; Lin, Hua-Kuo; Chiu, Hsun; Lee, Don-Ching; Chung, Yu-Fen; Chiu, Ing-Ming

    2015-03-01

    FGF1 is involved in multiple biological functions and exhibits the importance in neuroprotective effects. Our previous studies indicated that, in human brain and retina, the FGF1B promoter controlled the expression of FGF1. However, the exact function and regulation of FGF1 in brain is still unclear. Here, we generated F1B-GFP transgenic mice that expressed the GFP reporter gene under the control of human FGF1B promoter (-540 to +31). Using the fresh brain sections of F1B-GFP transgenic mice, we found that the F1B-GFP cells expressed strong fluorescent signals in the ventricular system throughout the brain. The results of immunohistochemistry further showed that two distinct populations of F1B-GFP(+) cells existed in the brains of F1B-GFP transgenic mice. We demonstrated that one population of F1B-GFP(+) cells was ependymal cells, which distributed along the entire ventricles, and the second population of F1B-GFP(+) cells was neuronal cells that projected their long processes into multiple directions in specific areas of the brain. The double labeling of F1B-GFP(+) cells and tyrosine hydroxylase indicated that a subpopulation of F1B-GFP(+) -neuronal cells was dopaminergic neurons. Importantly, these F1B-GFP(+) /TH(+) cells were distributed in the main dopaminergic neuronal groups including hypothalamus, ventral tegmental area, and raphe nuclei. These results suggested that human FGF1B promoter was active in ependymal cells, neurons, and a portion of dopaminergic neurons. Thus, the F1B-GFP transgenic mice provide an animal model not only for studying FGF1 gene expression in vivo but also for understanding the role of FGF1 contribution in neurodegenerative disorders such as Parkinson's disease and Alzheimer's disease. © 2014 The Authors Developmental Neurobiology Published by Wiley Periodicals, Inc.

  11. DNA replication checkpoint promotes G1-S transcription by inactivating the MBF repressor Nrm1

    PubMed Central

    de Bruin, R. A. M.; Kalashnikova, T. I.; Aslanian, A.; Wohlschlegel, J.; Chahwan, C.; Yates, J. R.; Russell, P.; Wittenberg, C.

    2008-01-01

    The cell cycle transcriptional program imposes order on events of the cell-cycle and is a target for signals that regulate cell-cycle progression, including checkpoints required to maintain genome integrity. Neither the mechanism nor functional significance of checkpoint regulation of the cell-cycle transcription program are established. We show that Nrm1, an MBF-specific transcriptional repressor acting at the transition from G1 to S phase of the cell cycle, is at the nexus between the cell cycle transcriptional program and the DNA replication checkpoint in fission yeast. Phosphorylation of Nrm1 by the Cds1 (Chk2) checkpoint protein kinase, which is activated in response to DNA replication stress, promotes its dissociation from the MBF transcription factor. This leads to the expression of genes encoding components that function in DNA replication and repair pathways important for cell survival in response to arrested DNA replication. PMID:18682565

  12. The oncoprotein HBXIP upregulates PDGFB via activating transcription factor Sp1 to promote the proliferation of breast cancer cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Yingyi; Zhao, Yu; Li, Leilei

    2013-05-03

    Highlights: •HBXIP is able to upregulate the expression of PDGFB in breast cancer cells. •HBXIP serves as a coactivator of activating transcription factor Sp1. •HBXIP stimulates the PDGFB promoter via activating transcription factor Sp1. •HBXIP promotes the proliferation of breast cancer cell via upregulating PDGFB. -- Abstract: We have reported that the oncoprotein hepatitis B virus X-interacting protein (HBXIP) acts as a novel transcriptional coactivator to promote proliferation and migration of breast cancer cells. Previously, we showed that HBXIP was able to activate nuclear factor-κB (NF-κB) in breast cancer cells. As an oncogene, the platelet-derived growth factor beta polypeptide (PDGFB)more » plays crucial roles in carcinogenesis. In the present study, we found that both HBXIP and PDGFB were highly expressed in breast cancer cell lines. Interestingly, HBXIP was able to increase transcriptional activity of NF-κB through PDGFB, suggesting that HBXIP is associated with PDGFB in the cells. Moreover, HBXIP was able to upregulate PDGFB at the levels of mRNA, protein and promoter in the cells. Then, we identified that HBXIP stimulated the promoter of PDGFB through activating transcription factor Sp1. In function, HBXIP enhanced the proliferation of breast cancer cells through PDGFB in vitro. Thus, we conclude that HBXIP upregulates PDGFB via activating transcription factor Sp1 to promote proliferation of breast cancer cells.« less

  13. Differential SLC1A2 Promoter Methylation in Bipolar Disorder With or Without Addiction

    PubMed Central

    Jia, Yun-Fang; Choi, YuBin; Ayers-Ringler, Jennifer R.; Biernacka, Joanna M.; Geske, Jennifer R.; Lindberg, Daniel R.; McElroy, Susan L.; Frye, Mark A.; Choi, Doo-Sup; Veldic, Marin

    2017-01-01

    While downregulation of excitatory amino acid transporter 2 (EAAT2), the main transporter removing glutamate from the synapse, has been recognized in bipolar disorder (BD), the underlying mechanisms of downregulation have not been elucidated. BD is influenced by environmental factors, which may, via epigenetic modulation of gene expression, differentially affect illness presentation. This study thus focused on epigenetic DNA methylation regulation of SLC1A2, encoding for EAAT2, in BD with variable environmental influences of addiction. High resolution melting PCR (HRM-PCR) and thymine–adenine (TA) cloning with sequence analysis were conducted to examine methylation of the promoter region of the SLC1A2. DNA was isolated from blood samples drawn from BD patients (N = 150) with or without addiction to alcohol, nicotine, or food, defined as binge eating, and matched controls (N = 32). In comparison to controls, the SLC1A2 promoter region was hypermethylated in BD without addiction but was hypomethylated in BD with addiction. After adjusting for age and sex, the association of methylation levels with nicotine addiction (p = 0.0009) and binge eating (p = 0.0002) remained significant. Consistent with HRM-PCR, direct sequencing revealed increased methylation in CpG site 6 in BD, but decreased methylation in three CpG sites (6, 48, 156) in BD with alcohol and nicotine addictions. These results suggest that individual point methylation within the SLC1A2 promoter region may be modified by exogenous addiction and may have a potential for developing clinically valuable epigenetic biomarkers for BD diagnosis and monitoring. PMID:28785205

  14. Differential SLC1A2 Promoter Methylation in Bipolar Disorder With or Without Addiction.

    PubMed

    Jia, Yun-Fang; Choi, YuBin; Ayers-Ringler, Jennifer R; Biernacka, Joanna M; Geske, Jennifer R; Lindberg, Daniel R; McElroy, Susan L; Frye, Mark A; Choi, Doo-Sup; Veldic, Marin

    2017-01-01

    While downregulation of excitatory amino acid transporter 2 (EAAT2), the main transporter removing glutamate from the synapse, has been recognized in bipolar disorder (BD), the underlying mechanisms of downregulation have not been elucidated. BD is influenced by environmental factors, which may, via epigenetic modulation of gene expression, differentially affect illness presentation. This study thus focused on epigenetic DNA methylation regulation of SLC1A2 , encoding for EAAT2, in BD with variable environmental influences of addiction. High resolution melting PCR (HRM-PCR) and thymine-adenine (TA) cloning with sequence analysis were conducted to examine methylation of the promoter region of the SLC1A2 . DNA was isolated from blood samples drawn from BD patients ( N = 150) with or without addiction to alcohol, nicotine, or food, defined as binge eating, and matched controls ( N = 32). In comparison to controls, the SLC1A2 promoter region was hypermethylated in BD without addiction but was hypomethylated in BD with addiction. After adjusting for age and sex, the association of methylation levels with nicotine addiction ( p = 0.0009) and binge eating ( p = 0.0002) remained significant. Consistent with HRM-PCR, direct sequencing revealed increased methylation in CpG site 6 in BD, but decreased methylation in three CpG sites (6, 48, 156) in BD with alcohol and nicotine addictions. These results suggest that individual point methylation within the SLC1A2 promoter region may be modified by exogenous addiction and may have a potential for developing clinically valuable epigenetic biomarkers for BD diagnosis and monitoring.

  15. PAI-1 expression and its regulation by promoter 4G/5G polymorphism in clear cell renal cell carcinoma.

    PubMed

    Choi, Jung-Woo; Lee, Ju-Han; Park, Hong Seok; Kim, Young-Sik

    2011-10-01

    To characterise patients with high plasminogen activator inhibitor-1 (PAI-1) expression as oral PAI-1 antagonists are currently in preclinical trials, and to determine whether the PAI-1 promoter 4G/5G polymorphism regulates PAI-1 expression in clear cell renal cell carcinoma (CCRCC). PAI-1 expression was examined by immunohistochemistry in 69 CCRCC specimens. In addition, the promoter 4G/5G polymorphism was investigated by both allele-specific PCR and direct DNA sequencing. PAI-1 was overexpressed in 25/69 (36.2%) patients with CCRCC. PAI-1 staining was intense in tumour cells with a high Fuhrman nuclear grade and in spindle-shaped tumour cells. PAI-1 expression was significantly associated with older age at diagnosis (p=0.027), high nuclear grade (p<0.001), advanced clinical stage (p=0.030) and distant metastasis (p=0.009). In survival analyses, PAI-1 expression was correlated with disease-free survival in Kaplan-Meier curves (p=0.015) but was not significant in the Cox hazards model (p=0.527). The frequencies of the promoter polymorphism were 24.6% (17/69) 4G/4G, 43.5% (30/69) 4G/5G and 31.9% (22/69) 5G/5G. The homozygous 4G/4G or 5G/5G group showed a tendency for a high nuclear grade (p=0.05) but the 4G/5G polymorphism was not related to other prognostic parameters. PAI-1 expression was poorly correlated with its promoter 4G/5G polymorphism (Spearman ρ=0.088). CCRCC with high PAI-1 expression is characterised by older age, high nuclear grade, advanced stage, distant metastasis and/or shortened disease-free survival. PAI-1 expression is not affected by the promoter 4G/5G polymorphism.

  16. Caveolin 1-related autophagy initiated by aldosterone-induced oxidation promotes liver sinusoidal endothelial cells defenestration.

    PubMed

    Luo, Xiaoying; Dan Wang; Luo, Xuan; Zhu, Xintao; Wang, Guozhen; Ning, Zuowei; Li, Yang; Ma, Xiaoxin; Yang, Renqiang; Jin, Siyi; Huang, Yun; Meng, Ying; Li, Xu

    2017-10-01

    Aldosterone, with pro-oxidation and pro-autophagy capabilities, plays a key role in liver fibrosis. However, the mechanisms underlying aldosterone-promoted liver sinusoidal endothelial cells (LSECs) defenestration remain unknown. Caveolin 1 (Cav1) displays close links with autophagy and fenestration. Hence, we aim to investigate the role of Cav1-related autophagy in LSECs defenestration. We found the increase of aldosterone/MR (mineralocorticoid receptor) level, oxidation, autophagy, and defenestration in LSECs in the human fibrotic liver, BDL or hyperaldosteronism models; while antagonizing aldosterone or inhibiting autophagy relieved LSECs defenestration in BDL-induced fibrosis or hyperaldosteronism models. In vitro, fenestrae of primary LSECs gradually shrank, along with the down-regulation of the NO-dependent pathway and the augment of the AMPK-dependent autophagy; these effects were aggravated by rapamycin (an autophagy activator) or aldosterone treatment. Additionally, aldosterone increased oxidation mediated by Cav1, reduced ATP generation, and subsequently induced the AMPK-dependent autophagy, leading to the down-regulation of the NO-dependent pathway and LSECs defenestration. These effects were reversed by MR antagonist spironolactone, antioxidants or autophagy inhibitors. Besides, aldosterone enhanced the co-immunoprecipitation of Cav1 with p62 and ubiquitin, and induced Cav1 co-immunofluorescence staining with LC3, ubiquitin, and F-actin in the perinuclear area of LSECs. Furthermore, aldosterone treatment increased the membrane protein level of Cav1, whereas decrease the cytoplasmic protein level of Cav1, indicating that aldosterone induced Cav1-related selective autophagy and F-actin remodeling to promote defenestration. Consequently, Cav1-related selective autophagy initiated by aldosterone-induced oxidation promotes LSECs defenestration via activating the AMPK-ULK1 pathway and inhibiting the NO-dependent pathway. Copyright © 2017 The Authors

  17. IQGAP1 mediates the disruption of adherens junctions to promote Escherichia coli K1 invasion of brain endothelial cells.

    PubMed

    Krishnan, Subramanian; Fernandez, G Esteban; Sacks, David B; Prasadarao, Nemani V

    2012-09-01

    The transcellular entry of Escherichia coli K1 through human brain microvascular endothelial cells (HBMEC) is responsible for tight junction disruption, leading to brain oedema in neonatal meningitis. Previous studies demonstrated that outer membrane protein A (OmpA) of E. coli K1 interacts with its receptor, Ecgp96, to induce PKC-α phosphorylation, adherens junction (AJ) disassembly (by dislodging β-catenin from VE-cadherin), and remodelling of actin in HBMEC. We report here that IQGAP1 mediates β-catenin dissociation from AJs to promote actin polymerization required for E. coli K1 invasion of HBMEC. Overexpression of C-terminal truncated IQGAP1 (IQΔC) that cannot bind β-catenin prevents both AJ disruption and E. coli K1 entry. Of note, phospho-PKC-α interacts with the C-terminal portion of Ecgp96 as well as with VE-cadherin after IQGAP1-mediated AJ disassembly. HBMEC overexpressing either C-terminal truncated Ecgp96 (Ecgp96Δ200) or IQΔC upon infection with E. coli showed no interaction of phospho-PKC-α with Ecgp96. These data indicate that the binding of OmpA to Ecgp96 induces PKC-α phosphorylation and association of phospho-PKC-α with Ecgp96, and then signals IQGAP1 to detach β-catenin from AJs. Subsequently, IQGAP1/β-catenin bound actin translocates to the site of E. coli K1 attachment to promote invasion. © 2012 Blackwell Publishing Ltd.

  18. IQGAP1 mediates the disruption of adherens junctions to promote Escherichia coli K1 invasion of brain endothelial cells

    PubMed Central

    Krishnan, Subramanian; Fernandez, G. Esteban; Sacks, David B.; Prasadarao, Nemani V.

    2012-01-01

    The transcellular entry of E. coli K1 through human brain microvascular endothelial cells (HBMEC) is responsible for tight junction disruption, leading to brain edema in neonatal meningitis. Previous studies demonstrated that outer membrane protein A (OmpA) of E. coli K1 interacts with its receptor, Ecgp96 to induce PKC-α phosphorylation, adherens junction (AJ) disassembly (by dislodging β-catenin from VE-cadherin), and remodeling of actin in HBMEC. We report here that IQGAP1 mediates β-catenin dissociation from AJs to promote actin polymerization required for E. coli K1 invasion of HBMEC. Overexpression of C-terminal truncated IQGAP1 (IQΔC) that cannot bind β-catenin prevents both AJ disruption and E. coli K1 entry. Of note, phospho-PKC-α interacts with the C-terminal portion of Ecgp96 as well as with VE-cadherin after IQGAP1 mediated AJ disassembly. HBMEC overexpressing either C-terminal truncated Ecgp96 (Ecgp96Δ200) or IQΔC upon infection with E. coli showed no interaction of phospho-PKC-α with Ecgp96. These data indicate that the binding of OmpA to Ecgp96 induces PKC-α phosphorylation and association of phospho-PKC-α with Ecgp96, and then signals IQGAP1 to detach β-catenin from AJs. Subsequently, IQGAP1/β-catenin bound actin translocates to the site of E. coli K1 attachment to promote invasion. PMID:22519731

  19. E2F mediates induction of the Sp1-controlled promoter of the human DNA polymerase ɛ B-subunit gene POLE2

    PubMed Central

    Huang, Deqi; Jokela, Maarit; Tuusa, Jussi; Skog, Sven; Poikonen, Kari; Syväoja, Juhani E.

    2001-01-01

    The B-subunits of replicative DNA polymerases from Archaea to humans belong to the same protein family, suggesting that they share a common fundamental function. We report here the gene structure for the B-subunit of human DNA polymerase ɛ (POLE2), whose expression and transcriptional regulation is typical for replication proteins with some unique features. The 75 bp core promoter region, located within exon 1, contains an Sp1 element that is a critical determinant of promoter activity as shown by the luciferase reporter, electrophoretic mobility shift and DNase I footprinting assays. Two overlapping E2F elements adjacent to the Sp1 element are essential for full promoter activity and serum response. Binding sites for E2F1 and NF-1 reside immediately downstream from the core promoter region. Our results suggest that human POLE2 is regulated by two E2F–pocket protein complexes, one associated with Sp1 and the other with NF-1. So far, only one replicative DNA polymerase B-subunit gene promoter, POLA2 encoding the B-subunit of DNA polymerase α, has been characterized. Mitogenic activation of the POLE2 promoter by an E2F-mediated mechanism resembles that of POLA2, but the regulation of basal promoter activity is different between these two genes. PMID:11433027

  20. Beta-adrenergic signaling promotes tumor angiogenesis and prostate cancer progression through HDAC2-mediated suppression of thrombospondin-1.

    PubMed

    Hulsurkar, M; Li, Z; Zhang, Y; Li, X; Zheng, D; Li, W

    2017-03-01

    Chronic behavioral stress and beta-adrenergic signaling have been shown to promote cancer progression, whose underlying mechanisms are largely unclear, especially the involvement of epigenetic regulation. Histone deacetylase-2 (HDAC2), an epigenetic regulator, is critical for stress-induced cardiac hypertrophy. It is unknown whether it is necessary for beta-adrenergic signaling-promoted cancer progression. Using xenograft models, we showed that chronic behavioral stress and beta-adrenergic signaling promote angiogenesis and prostate cancer progression. HDAC2 was induced by beta-adrenergic signaling in vitro and in mouse xenografts. We next uncovered that HDAC2 is a direct target of cAMP response element-binding protein (CREB) that is activated by beta-adrenergic signaling. Notably, HDAC2 is necessary for beta-adrenergic signaling to induce angiogenesis. We further demonstrated that, upon CREB activation, HDAC2 represses thrombospondin-1 (TSP1), a potent angiogenesis inhibitor, through epigenetic regulation. Together, these data establish a novel pathway that HDAC2 and TSP1 act downstream of CREB activation in beta-adrenergic signaling to promote cancer progression.

  1. Sp1-CD147 positive feedback loop promotes the invasion ability of ovarian cancer.

    PubMed

    Zhao, Jing; Ye, Wei; Wu, Juan; Liu, Lijuan; Yang, Lina; Gao, Lu; Chen, Biliang; Zhang, Fanglin; Yang, Hong; Li, Yu

    2015-07-01

    CD147 is a novel cancer biomarker that has been confirmed to be overexpressed in ovarian carcinoma, which is significantly associated with poor prognosis. Although the Sp1 protein regulates the expression level of CD147, it remains unclear whether Sp1 phosphorylation plays a role in this regulation. A dual-luciferase assay revealed that T453 and T739 mutations decreased the activity of Sp1 binding to the promoter of CD147, followed by a decrease in CD147 mRNA and protein expression. Western blot analysis showed that CD147 promoted Sp1 phosphorylation at T453 and T739 through the PI3K/AKT and MAPK/ERK pathways. In addition, blocking the Sp1-CD147 positive feedback loop reduced the invasion ability of HO-8910pm cells. Immunohistochemical staining showed that the components of the feedback loop were overexpressed in ovarian cancer tissues. The correlation analysis revealed a significant correlation between phospho-Sp1 (T453), phospho-Sp1 (T739) and CD147 expression levels, with correlation coefficients of r=0.477 and r=0.461, respectively. Collectively, our results suggest that a Sp1-CD147 positive feedback loop plays a critical role in the invasion ability of ovarian cancer cells.

  2. The SRE Motif in the Human PNPLA3 Promoter (-97 to -88 bp) Mediates Transactivational Effects of SREBP-1c.

    PubMed

    Liang, Hua; Xu, Jing; Xu, Fen; Liu, Hongxia; Yuan, Ding; Yuan, Shuhua; Cai, Mengyin; Yan, Jinhua; Weng, Jianping

    2015-09-01

    Patatin-like phospholipase domain containing 3 (PNPLA3) is a non-secreted protein primarily expressed in liver and adipose tissue. Recently, numerous genetic studies have shown that PNPLA3 is a major susceptibility gene for nonalcoholic fatty liver disease (NAFLD). However, the mechanism involved in transcriptional regulation of the PNPLA3 gene remains unknown. We performed a detailed analysis of the human PNPLA3 gene promoter and identified two novel cis-acting elements (SRE and NFY binding motifs) located at -97/-88 and -26/-22 bp, respectively. Overexpression of SREBP-1c in HepG2 cells significantly increased PNPLA3 promoter activity. Mutation of either of the putative SRE or NFY binding motifs blocked the transactivation effects of SREBP-1c on the promoter. Overexpression of SREBP-1c and NFY together increased PNPLA3 promoter activity twice as much as that of SREBP-1c or NFY expression alone. This result suggests that SREBP-1c and NFY synergistically transactivate the human PNPLA3 gene. The ability of SREBP-1c and NFY to bind these cis-elements was confirmed using gel shift analysis. Putative SRE and NFY motifs also mediated synergistic insulin-induced transactivation of the PNPLA3 promoter in HepG2 cells. Additionally, the ability of SREBP-1c to bind to the PNPLA3 promoter was increased by insulin in a dose-dependent manner. Moreover, the treatment of HepG2 cells with the PI3K inhibitor LY294002 led to reduced insulin promoter-activating ability accompanied by a decrease in PNPLA3 and SREBP-1c protein expression. These results demonstrate that SREBP-1c is a direct activator of the human PNPLA3 gene and insulin transactivates the PNPLA3 gene via the PI3K-SREBP-1c/NFY pathway in HepG2 cells. © 2015 Wiley Periodicals, Inc.

  3. Fluid shear stress activates YAP1 to promote cancer cell motility

    NASA Astrophysics Data System (ADS)

    Lee, Hyun Jung; Diaz, Miguel F.; Price, Katherine M.; Ozuna, Joyce A.; Zhang, Songlin; Sevick-Muraca, Eva M.; Hagan, John P.; Wenzel, Pamela L.

    2017-01-01

    Mechanical stress is pervasive in egress routes of malignancy, yet the intrinsic effects of force on tumour cells remain poorly understood. Here, we demonstrate that frictional force characteristic of flow in the lymphatics stimulates YAP1 to drive cancer cell migration; whereas intensities of fluid wall shear stress (WSS) typical of venous or arterial flow inhibit taxis. YAP1, but not TAZ, is strictly required for WSS-enhanced cell movement, as blockade of YAP1, TEAD1-4 or the YAP1-TEAD interaction reduces cellular velocity to levels observed without flow. Silencing of TEAD phenocopies loss of YAP1, implicating transcriptional transactivation function in mediating force-enhanced cell migration. WSS dictates expression of a network of YAP1 effectors with executive roles in invasion, chemotaxis and adhesion downstream of the ROCK-LIMK-cofilin signalling axis. Altogether, these data implicate YAP1 as a fluid mechanosensor that functions to regulate genes that promote metastasis.

  4. [Promoter hypermethylation status of the mismatch repair gene hMLH1 in patients with sporadic renal cell carcinoma].

    PubMed

    Salinas-Sánchez, Antonio S; Rubio-del-Campo, Antonio; Sánchez-Sánchez, Francisco; Giménez-Bachs, José M; Donate-Moreno, María J; García-Olmo, Dolores C; Escribano-Martínez, Julio

    2006-04-01

    Epigenetic inactivation is a gene function abnormality that produces no changes in the DNA sequence, with the most frequent epigenetic alteration being hypermethylation of CpG islands in the promoter regions of the genes. Based on recent indications of a potential relationship between mismatch repair genes and renal cell carcinoma (RCC), we were interested in investigating the existence of promoter hypermethylation of the hMLH1 gene in tumor DNA samples from patients with sporadic RCC. Sixty-five tumor tissue specimens were collected consecutively. The DNA was first obtained and purified, then digested with the restriction enzymes Hpa II and Msp I, followed by polimerase chain reaction amplification of 3 promoter regions of the hMLH1 gene, agarose gel electrophoresis, and densitometric analysis of the images of the amplified bands. Mean patient age was 63.7 years. The most frequent cell type was clear cell carcinoma (67.7%). 73.9% of tumors were diagnosed in stages below pT2, 9.3% had gland involvement and 20%, distant metastasis. No somatic hypermethylation was detected in the promoter region of the hMLH1 gene in any of the patients studied. Our data indicate that promoter hypermethylation of the hMLH1 gene is not implicated in the pathogenesis of sporadic RCC, and therefore the existence of another type of mutation, microsatellite instability and/or loss of heterozygosity should be examined to determine the possible role of this gene in sporadic RCC.

  5. Health-promoting schools: an opportunity for oral health promotion.

    PubMed Central

    Kwan, Stella Y. L.; Petersen, Poul Erik; Pine, Cynthia M.; Borutta, Annerose

    2005-01-01

    Schools provide an important setting for promoting health, as they reach over 1 billion children worldwide and, through them, the school staff, families and the community as a whole. Health promotion messages can be reinforced throughout the most influential stages of children's lives, enabling them to develop lifelong sustainable attitudes and skills. Poor oral health can have a detrimental effect on children's quality of life, their performance at school and their success in later life. This paper examines the global need for promoting oral health through schools. The WHO Global School Health Initiative and the potential for setting up oral health programmes in schools using the health-promoting school framework are discussed. The challenges faced in promoting oral health in schools in both developed and developing countries are highlighted. The importance of using a validated framework and appropriate methodologies for the evaluation of school oral health projects is emphasized. PMID:16211159

  6. mTORC1 Inhibition via Rapamycin Promotes Triacylglycerol Lipolysis and Release of Free Fatty Acids in 3T3-L1 Adipocytes

    PubMed Central

    Soliman, Ghada A.; Acosta-Jaquez, Hugo A.; Fingar, Diane C.

    2017-01-01

    Signaling by mTOR complex 1 (mTORC1) promotes anabolic cellular processes in response to growth factors, nutrients, and hormonal cues. Numerous clinical trials employing the mTORC1 inhibitor rapamycin (aka sirolimus) to immuno-suppress patients following organ transplantation have documented the development of hypertriglyceridemia and elevated serum free fatty acids (FFA). We therefore investigated the cellular role of mTORC1 in control of triacylglycerol (TAG) metabolism using cultured murine 3T3-L1 adipocytes. We found that treatment of adipocytes with rapamycin reduced insulin-stimulated TAG storage ~50%. To determine whether rapamycin reduces TAG storage by upregulating lipolytic rate, we treated adipocytes in the absence and presence of rapamycin and isoproterenol, a β2-adrenergic agonist that activates the cAMP/protein kinase A (PKA) pathway to promote lipolysis. We found that rapamycin augmented isoproterenol-induced lipolysis without altering cAMP levels. Rapamycin enhanced the isoproterenol-stimulated phosphorylation of hormone sensitive lipase (HSL) on Ser-563 (a PKA site), but had no effect on the phosphorylation of HSL S565 (an AMPK site). Additionally, rapamycin did not affect the isoproterenol-mediated phosphorylation of perilipin, a protein that coats the lipid droplet to initiate lipolysis upon phosphorylation by PKA. These data demonstrate that inhibition of mTORC1 signaling synergizes with the β-adrenergic-cAMP/PKA pathway to augment phosphorylation of HSL to promote hormone-induced lipolysis. Moreover, they reveal a novel metabolic function for mTORC1; mTORC1 signaling suppresses lipolysis, thus augmenting TAG storage. PMID:21042876

  7. Chk1 promotes replication fork progression by controlling replication initiation

    PubMed Central

    Petermann, Eva; Woodcock, Mick; Helleday, Thomas

    2010-01-01

    DNA replication starts at initiation sites termed replication origins. Metazoan cells contain many more potential origins than are activated (fired) during each S phase. Origin activation is controlled by the ATR checkpoint kinase and its downstream effector kinase Chk1, which suppresses origin firing in response to replication blocks and during normal S phase by inhibiting the cyclin-dependent kinase Cdk2. In addition to increased origin activation, cells deficient in Chk1 activity display reduced rates of replication fork progression. Here we investigate the causal relationship between increased origin firing and reduced replication fork progression. We use the Cdk inhibitor roscovitine or RNAi depletion of Cdc7 to inhibit origin firing in Chk1-inhibited or RNAi-depleted cells. We report that Cdk inhibition and depletion of Cdc7 can alleviate the slow replication fork speeds in Chk1-deficient cells. Our data suggest that increased replication initiation leads to slow replication fork progression and that Chk1 promotes replication fork progression during normal S phase by controlling replication origin activity. PMID:20805465

  8. PINK1 deficiency impairs mitochondrial homeostasis and promotes lung fibrosis

    PubMed Central

    Bueno, Marta; Lai, Yen-Chun; Romero, Yair; Brands, Judith; St. Croix, Claudette M.; Kamga, Christelle; Corey, Catherine; Herazo-Maya, Jose D.; Sembrat, John; Lee, Janet S.; Duncan, Steve R.; Rojas, Mauricio; Shiva, Sruti; Chu, Charleen T.; Mora, Ana L.

    2014-01-01

    Although aging is a known risk factor for idiopathic pulmonary fibrosis (IPF), the pathogenic mechanisms that underlie the effects of advancing age remain largely unexplained. Some age-related neurodegenerative diseases have an etiology that is related to mitochondrial dysfunction. Here, we found that alveolar type II cells (AECIIs) in the lungs of IPF patients exhibit marked accumulation of dysmorphic and dysfunctional mitochondria. These mitochondrial abnormalities in AECIIs of IPF lungs were associated with upregulation of ER stress markers and were recapitulated in normal mice with advancing age in response to stimulation of ER stress. We found that impaired mitochondria in IPF and aging lungs were associated with low expression of PTEN-induced putative kinase 1 (PINK1). Knockdown of PINK1 expression in lung epithelial cells resulted in mitochondria depolarization and expression of profibrotic factors. Moreover, young PINK1-deficient mice developed similarly dysmorphic, dysfunctional mitochondria in the AECIIs and were vulnerable to apoptosis and development of lung fibrosis. Our data indicate that PINK1 deficiency results in swollen, dysfunctional mitochondria and defective mitophagy, and promotes fibrosis in the aging lung. PMID:25562319

  9. Computational prediction and experimental verification of HVA1-like abscisic acid responsive promoters in rice (Oryza sativa).

    PubMed

    Ross, Christian; Shen, Qingxi J

    2006-09-01

    Abscisic acid (ABA) is one of the central plant hormones, responsible for controlling both maturation and germination in seeds, as well as mediating adaptive responses to desiccation, injury, and pathogen infection in vegetative tissues. Thorough analyses of two barley genes, HVA1 and HVA22, indicate that their response to ABA relies on the interaction of two cis-acting elements in their promoters, an ABA response element (ABRE) and a coupling element (CE). Together, they form an ABA response promoter complex (ABRC). Comparison of promoters of barley HVA1 and it rice orthologue indicates that the structures and sequences of their ABRCs are highly similar. Prediction of ABA responsive genes in the rice genome is then tractable to a bioinformatics approach based on the structures of the well-defined barley ABRCs. Here we describe a model developed based on the consensus, inter-element spacing and orientations of experimentally determined ABREs and CEs. Our search of the rice promoter database for promoters that fit the model has generated a partial list of genes in rice that have a high likelihood of being involved in the ABA signaling network. The ABA inducibility of some of the rice genes identified was validated with quantitative reverse transcription PCR (QPCR). By limiting our input data to known enhancer modules and experimentally derived rules, we have generated a high confidence subset of ABA-regulated genes. The results suggest that the pathways by which cereals respond to biotic and abiotic stresses overlap significantly, and that regulation is not confined to the level transcription. The large fraction of putative regulatory genes carrying HVA1-like enhancer modules in their promoters suggests the ABA signal enters at multiple points into a complex regulatory network that remains largely unmapped.

  10. Regulation and function of the pepper pectin methylesterase inhibitor (CaPMEI1) gene promoter in defense and ethylene and methyl jasmonate signaling in plants.

    PubMed

    An, Soo Hyun; Choi, Hyong Woo; Hong, Jeum Kyu; Hwang, Byung Kook

    2009-11-01

    Analysis of the promoters of defense-related genes is valuable for determining stress signaling and transcriptional activation during pathogen infection. Here, we have isolated and functionally characterized the promoter region of the pepper (Capsicum annuum) pectin methylesterase inhibitor 1 (CaPMEI1) gene in transiently transformed tobacco plants and stably transformed Arabidopsis plants. Among four 5' deletion constructs analyzed, the -958-bp CaPMEI1 promoter induced a high level of GUS reporter activity in tobacco leaf tissue, driven by pathogen infection as well as by ethylene and methyl jasmonate (MeJA) treatment. The 204-bp region from -958 bp to -754 bp of the CaPMEI1 promoter is responsible for the stress-responsive expression. In addition, the pepper transcription factor CARAV1 activated the CaPMEI1 promoter in tobacco leaves, whereas the transcription factor CAbZIP1 did not. In the transgenic Arabidopsis plants, the -958 bp CaPMEI1 promoter was functionally regulated by developmental cues, bacterial and oomycete pathogen infections, and treatment with ethylene and MeJA. Histochemical GUS staining analyses of Arabidopsis tissues revealed that the CaPMEI1 promoter was mainly activated in leaf veins in response to various biotic and abiotic stimuli. Together, these results suggest that CaPMEI1 promoter activation may be a critical molecular event for host defense response and ethylene- and MeJA-mediated CaPMEI1 gene expression.

  11. Pregnancy and Smoothelin-like Protein 1 (SMTNL1) Deletion Promote the Switching of Skeletal Muscle to a Glycolytic Phenotype in Human and Mice.

    PubMed

    Lontay, Beata; Bodoor, Khaldon; Sipos, Adrienn; Weitzel, Douglas H; Loiselle, David; Safi, Rachid; Zheng, Donghai; Devente, James; Hickner, Robert C; McDonnell, Donald P; Ribar, Thomas; Haystead, Timothy A

    2015-07-17

    Pregnancy promotes physiological adaptations throughout the body, mediated by the female sex hormones progesterone and estrogen. Changes in the metabolic properties of skeletal muscle enable the female body to cope with the physiological challenges of pregnancy and may also be linked to the development of insulin resistance. We conducted global microarray, proteomic, and metabolic analyses to study the role of the progesterone receptor and its transcriptional regulator, smoothelin-like protein 1 (SMTNL1) in the adaptation of skeletal muscle to pregnancy. We demonstrate that pregnancy promotes fiber-type changes from an oxidative to glycolytic isoform in skeletal muscle. This phenomenon is regulated through an interaction between SMTNL1 and progesterone receptor, which alters the expression of contractile and metabolic proteins. smtnl1(-/-) mice are metabolically less efficient and show impaired glucose tolerance. Pregnancy antagonizes these effects by inducing metabolic activity and increasing glucose tolerance. Our results suggest that SMTNL1 has a role in mediating the actions of steroid hormones to promote fiber switching in skeletal muscle during pregnancy. Our findings also bear on the management of gestational diabetes that develops as a complication of pregnancy in ~4% of women. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  12. Y-box-binding protein-1 (YB-1) promotes cell proliferation, adhesion and drug resistance in diffuse large B-cell lymphoma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Miao, Xiaobing; Wu, Yaxun; Wang, Yuchan

    YB-1 is a multifunctional protein, which has been shown to correlate with resistance to treatment of various tumor types. This study investigated the expression and biologic function of YB-1 in diffuse large B-cell lymphoma (DLBCL). Immunohistochemical analysis showed that the expression statuses of YB-1 and pYB-1{sup S102} were reversely correlated with the clinical outcomes of DLBCL patients. In addition, we found that YB-1 could promote the proliferation of DLBCL cells by accelerating the G1/S transition. Ectopic expression of YB-1 could markedly increase the expression of cell cycle regulators cyclin D1 and cyclin E. Furthermore, we found that adhesion of DLBCLmore » cells to fibronectin (FN) could increase YB-1 phosphorylation at Ser102 and pYB-1{sup S102} nuclear translocation. In addition, overexpression of YB-1 could increase the adhesion of DLBCL cells to FN. Intriguingly, we found that YB-1 overexpression could confer drug resistance through cell-adhesion dependent and independent mechanisms in DLBCL. Silencing of YB-1 could sensitize DLBCL cells to mitoxantrone and overcome cell adhesion-mediated drug resistance (CAM-DR) phenotype in an AKT-dependent manner. - Highlights: • The expression statuses of YB-1 and pYB-1{sup S102} are reversely correlated with outcomes of DLBCL patients. • YB-1 promotes cell proliferation by accelerating G1/S transition in DLBCL. • YB-1 confers drug resistance to mitoxantrone in DLBCL.« less

  13. COL1A1 promotes metastasis in colorectal cancer by regulating the WNT/PCP pathway

    PubMed Central

    Zhang, Zheying; Wang, Yongxia; Zhang, Jinghang; Zhong, Jiateng; Yang, Rui

    2018-01-01

    Colorectal cancer (CRC) is the third leading cause of cancer-associated mortality, and is a major health problem. Collagen type I α 1 (COL1A1) is a major component of collagen type I. Recently, it was reported to be overexpressed in a variety of tumor tissues and cells. However, the function of COL1A1 in CRC remains unclear. Herein, the present study demonstrated that COL1A1 was upregulated in CRC tissues and the paired lymph node tissues. Transwell assays showed that COL1A1 promoted CRC cell migration in vitro. Moreover, it was revealed that COL1A1 levels were correlated with those of WNT/planar cell polarity (PCP) signaling pathway genes; inhibition of COL1A1 decreased the expression levels of Ras-related C3 botulinum toxin substrate 1-GTP, phosphorylated-c-Jun N-terminal kinase, and RhoA-GTP, all of which are key genes in the WNT/PCP signaling pathway. These results may indicate the mechanisms underlying the oncogenic role of COL1A1 in CRC. In summary, the present data indicated that COL1A1 may serve as an oncoprotein, and that it may be used as a potential therapeutic target in CRC. PMID:29393423

  14. Ethanol disrupts chondrification of the neurocranial cartilages in medaka embryos without affecting aldehyde dehydrogenase 1A2 (Aldh1A2) promoter methylation

    PubMed Central

    Hu, Yuhui; Willett, Kristine L.; Khan, Ikhlas A.; Scheffler, Brian E.; Dasmahapatra, Asok K.

    2009-01-01

    Medaka (Oryzias latipes) embryos at different developmental stages were exposed to ethanol for 48 h, then allowed to hatch. Teratogenic effects were evaluated in hatchlings after examining chondrocranial cartilage deformities. Ethanol disrupted cartilage development in medaka in a dose and developmental stage-specific manner. Compared to controls, the linear length of the neurocranium and other cartilages were reduced in ethanol-treated groups. Moreover, the chondrification in cartilages, specifically trabeculae and polar cartilages, were inhibited by ethanol. To understand the mechanism of ethanol teratogenesis, NAD+: NADH status during embryogenesis and the methylation pattern of Aldh1A2 promoter in whole embryos and adult tissues (brain, eye, heart and liver) were analyzed. Embryos 6 dpf had higher NAD+ than embryos 0 or 2 dpf. Ethanol (200 or 400 mM) was able to reduce NAD+ content in 2 and 6 dpf embryos. However, in both cases reductions were not significantly different from the controls. Moreover, no significant difference in either NADH content or in NAD+: NADH status of the ethanol-treated embryos, with regard to controls, was observed. The promoter of Aldh1A2 contains 31 CpG dinucleotides (-705 to +154, ATG = +1); none of which were methylated. Compared to controls, embryonic ethanol exposure (100 and 400 mM) was unable to alter Aldh1A2 promoter methylation in embryos or in the tissues of adults (breeding) developmentally exposed to ethanol (300 mM, 48 hpf). From these data we conclude that ethanol teratogenesis in medaka does not induce alteration in the methylation pattern of Aldh1A2 promoter, but does change cartilage development. PMID:19651241

  15. Live-cell analysis of endogenous GFP-RPB1 uncovers rapid turnover of initiating and promoter-paused RNA Polymerase II.

    PubMed

    Steurer, Barbara; Janssens, Roel C; Geverts, Bart; Geijer, Marit E; Wienholz, Franziska; Theil, Arjan F; Chang, Jiang; Dealy, Shannon; Pothof, Joris; van Cappellen, Wiggert A; Houtsmuller, Adriaan B; Marteijn, Jurgen A

    2018-05-08

    Initiation and promoter-proximal pausing are key regulatory steps of RNA Polymerase II (Pol II) transcription. To study the in vivo dynamics of endogenous Pol II during these steps, we generated fully functional GFP-RPB1 knockin cells. GFP-RPB1 photobleaching combined with computational modeling revealed four kinetically distinct Pol II fractions and showed that on average 7% of Pol II are freely diffusing, while 10% are chromatin-bound for 2.4 seconds during initiation, and 23% are promoter-paused for only 42 seconds. This unexpectedly high turnover of Pol II at promoters is most likely caused by premature termination of initiating and promoter-paused Pol II and is in sharp contrast to the 23 minutes that elongating Pol II resides on chromatin. Our live-cell-imaging approach provides insights into Pol II dynamics and suggests that the continuous release and reinitiation of promoter-bound Pol II is an important component of transcriptional regulation. Copyright © 2018 the Author(s). Published by PNAS.

  16. Adenovirus E4ORF1-induced MYC activation promotes host cell anabolic glucose metabolism and virus replication

    PubMed Central

    Thai, Minh; Graham, Nicholas A; Braas, Daniel; Nehil, Michael; Komisopoulou, Evangelia; Kurdistani, Siavash K.; McCormick, Frank; Graeber, Thomas G.; Christofk, Heather R.

    2014-01-01

    SUMMARY Virus infections trigger metabolic changes in host cells that support the bioenergetic and biosynthetic demands of viral replication. While recent studies have characterized virus-induced changes in host cell metabolism (Munger et al., 2008; Terry et al., 2012), the molecular mechanisms by which viruses reprogram cellular metabolism have remained elusive. Here we show that the gene product of adenovirus E4ORF1 is necessary for adenovirus-induced upregulation of host cell glucose metabolism and sufficient to promote enhanced glycolysis in cultured epithelial cells by activation of MYC. E4ORF1 localizes to the nucleus, binds to MYC, and enhances MYC binding to glycolytic target genes, resulting in elevated expression of specific glycolytic enzymes. E4ORF1 activation of MYC promotes increased nucleotide biosynthesis from glucose intermediates and enables optimal adenovirus replication in primary lung epithelial cells. Our findings show how a viral protein exploits host cell machinery to reprogram cellular metabolism and promote optimal progeny virion generation. PMID:24703700

  17. Parkin Protects Against Misfolded SOD1 Toxicity by Promoting Its Aggresome Formation and Autophagic Clearance.

    PubMed

    Yung, Cheryl; Sha, Di; Li, Lian; Chin, Lih-Shen

    2016-11-01

    Mutations in Cu/Zn superoxide dismutase (SOD1) cause autosomal dominant amyotrophic lateral sclerosis (ALS), a devastating neurodegenerative disease with no effective treatment. Despite ample evidence indicating involvement of mutation-induced SOD1 protein misfolding and aggregation in ALS pathogenesis, the molecular mechanisms that control cellular management of misfolded, aggregation-prone SOD1 mutant proteins remain unclear. Here, we report that parkin, an E3 ubiquitin-protein ligase which is linked to Parkinson's disease, is a novel regulator of cellular defense against toxicity induced by ALS-associated SOD1 mutant proteins. We find that parkin mediates K63-linked polyubiquitination of SOD1 mutants in cooperation with the UbcH13/Uev1a E2 enzyme and promotes degradation of these misfolded SOD1 proteins by the autophagy-lysosome system. In response to strong proteotoxic stress associated with proteasome impairment, parkin promotes sequestration of misfolded and aggregated SOD1 proteins to form perinuclear aggresomes, regulates positioning of lysosomes around misfolded SOD1 aggresomes, and facilitates aggresome clearance by autophagy. Our findings reveal parkin-mediated cytoprotective mechanisms against misfolded SOD1 toxicity and suggest that enhancing parkin-mediated cytoprotection may provide a novel therapeutic strategy for treating ALS.

  18. TRF2 Recruits RTEL1 to Telomeres in S Phase to Promote T-Loop Unwinding

    PubMed Central

    Sarek, Grzegorz; Vannier, Jean-Baptiste; Panier, Stephanie; Petrini, John H.J.; Boulton, Simon J.

    2015-01-01

    Summary The helicase RTEL1 promotes t-loop unwinding and suppresses telomere fragility to maintain the integrity of vertebrate telomeres. An interaction between RTEL1 and PCNA is important to prevent telomere fragility, but how RTEL1 engages with the telomere to promote t-loop unwinding is unclear. Here, we establish that the shelterin protein TRF2 recruits RTEL1 to telomeres in S phase, which is required to prevent catastrophic t-loop processing by structure-specific nucleases. We show that the TRF2-RTEL1 interaction is mediated by a metal-coordinating C4C4 motif in RTEL1, which is compromised by the Hoyeraal-Hreidarsson syndrome (HHS) mutation, RTEL1R1264H. Conversely, we define a TRF2I124D substitution mutation within the TRFH domain of TRF2, which eliminates RTEL1 binding and phenocopies the RTEL1R1264H mutation, giving rise to aberrant t-loop excision, telomere length heterogeneity, and loss of the telomere as a circle. These results implicate TRF2 in the recruitment of RTEL1 to facilitate t-loop disassembly at telomeres in S phase. PMID:25620558

  19. TRF2 recruits RTEL1 to telomeres in S phase to promote t-loop unwinding.

    PubMed

    Sarek, Grzegorz; Vannier, Jean-Baptiste; Panier, Stephanie; Petrini, John H J; Boulton, Simon J

    2015-02-19

    The helicase RTEL1 promotes t-loop unwinding and suppresses telomere fragility to maintain the integrity of vertebrate telomeres. An interaction between RTEL1 and PCNA is important to prevent telomere fragility, but how RTEL1 engages with the telomere to promote t-loop unwinding is unclear. Here, we establish that the shelterin protein TRF2 recruits RTEL1 to telomeres in S phase, which is required to prevent catastrophic t-loop processing by structure-specific nucleases. We show that the TRF2-RTEL1 interaction is mediated by a metal-coordinating C4C4 motif in RTEL1, which is compromised by the Hoyeraal-Hreidarsson syndrome (HHS) mutation, RTEL1(R1264H). Conversely, we define a TRF2(I124D) substitution mutation within the TRFH domain of TRF2, which eliminates RTEL1 binding and phenocopies the RTEL1(R1264H) mutation, giving rise to aberrant t-loop excision, telomere length heterogeneity, and loss of the telomere as a circle. These results implicate TRF2 in the recruitment of RTEL1 to facilitate t-loop disassembly at telomeres in S phase. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  20. Regulation of IL-8 promoter activity by verrucarin A in human monocytic THP-1 cells.

    PubMed

    Liu, Jun; Simmons, Steve O; Pei, Ruoting

    2014-01-01

    Macrocyclic trichothecenes have been frequently detected in fungi in water-damaged buildings and exhibited higher toxicity than the well-studied trichothecenes; however, the mechanism underlying their toxicity has been poorly understood. In this study, transcriptional regulation of the cytokine interleukin (IL)-8 by a macrocyclic trichothecene, verrucarin A (VA), in human monocytic THP-1 cells is reported. Consistent with previous findings, VA was 100-fold more cytotoxic than deoxynivalenol (DON), while ochratoxin A (OA) was not cytotoxic. In cells transduced with the wild-type IL-8 promoter luciferase construct, VA induced a biphasic dose response composed of an upregulation of luciferase expression at low concentrations of 0.01-1 ng/ml and a downregulation at high levels of 10 ng/ml and higher. In contrast, DON induced a sigmoid-shaped dose response with the EC50 of 11.6 ng/ml, while OA did not markedly affect the IL-8 expression. When cells were transduced with IL-8 promoter with a mutation of transcription factor nuclear factor-κB (NF-κB)-binding site, VA (1 ng/ml), DON (1000 ng/ml), and tumor necrosis factor (TNF) α (20 ng/ml)-induced luciferase expression were impaired. In addition, the NF-κB inhibitor caffeic acid phenethyl ester inhibited VA-, DON-, and TNFα-induced luciferase expression. Mutation of the CCAAT/enhancer-binding protein (CEBP) β binding site of the IL-8 promoter affected only DON-, but not VA- and TNFα-induced luciferase expression. Taken together, these results suggested that VA activated IL-8 promoter via an NF-κB-dependent, but not CEBPβ-dependent, pathway in human monocytes.

  1. Casein Kinase 1 Promotes Synchrony of the Circadian Clock Network

    PubMed Central

    Zheng, Xiangzhong; Sowcik, Mallory; Chen, Dechun

    2014-01-01

    Casein kinase 1, known as DOUBLETIME (DBT) in Drosophila melanogaster, is a critical component of the circadian clock that phosphorylates and promotes degradation of the PERIOD (PER) protein. However, other functions of DBT in circadian regulation are not clear, in part because severe reduction of dbt causes preadult lethality. Here we report the molecular and behavioral phenotype of a viable dbtEY02910 loss-of-function mutant. We found that DBT protein levels are dramatically reduced in adult dbtEY02910 flies, and the majority of mutant flies display arrhythmic behavior, with a few showing weak, long-period (∼32 h) rhythms. Peak phosphorylation of PER is delayed, and both hyper- and hypophosphorylated forms of the PER and CLOCK proteins are present throughout the day. In addition, molecular oscillations of the circadian clock are dampened. In the central brain, PER and TIM expression is heterogeneous and decoupled in the canonical clock neurons of the dbtEY02910 mutants. We also report an interaction between dbt and the signaling pathway involving pigment dispersing factor (PDF), a synchronizing peptide in the clock network. These data thus demonstrate that overall reduction of DBT causes long and arrhythmic behavior, and they reveal an unexpected role of DBT in promoting synchrony of the circadian clock network. PMID:24820422

  2. Cysteine dioxygenase type 1 promotes adipogenesis via interaction with peroxisome proliferator-activated receptor gamma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Deng, Peng; Chen, Yi; Ji, Ning

    Mammalian cysteine dioxygenase type 1 (CDO1) is an essential enzyme for taurine biosynthesis and the biodegradation of toxic cysteine. As previously suggested, Cdo1 may be a marker of liposarcoma progression and adipogenic differentiation, but the role of Cdo1 in adipogenesis has yet been reported. In this study, we found that the expression of Cdo1 is dramatically elevated during adipogenic differentiation of 3T3-L1 pre-adipocytes and mouse bone marrow-derived mesenchymal stem cells (mBMSCs). Conversely, knockdown of Cdo1 inhibited expression of adipogenic specific genes and lipid droplet formation in 3T3-L1 cells and mBMSCs. Mechanistically, we found Cdo1 interacted with Pparγ in response tomore » adipogenic stimulus. Further, depletion of Cdo1 reduced the recruitment of Pparγ to the promoters of C/EBPα and Fabp4. Collectively, our finding indicates that Cdo1 may be a co-activator of Pparγ in adipogenesis, and may contribute to the development of disease associated with excessive adipose tissue. - Highlights: • Cdo1expression is highly up-regulated during adipogenic differentiation of 3T3-L1 and mBMSCs. • Depletion of Cdo1 inhibited expression of adipogenic specific genes and lipid droplet formation. • Cdo1interacts with Pparγ during adipogenesis. • Knockdown of Cdo1 inhibited Pparγ binding to the promoters of C/EBPα and Fabp4.« less

  3. Nucleus Accumbens Shell and mPFC but Not Insula Orexin-1 Receptors Promote Excessive Alcohol Drinking

    PubMed Central

    Lei, Kelly; Wegner, Scott A.; Yu, Ji Hwan; Mototake, Arisa; Hu, Bing; Hopf, Frederic W.

    2016-01-01

    Addiction to alcohol remains a major social and economic problem, in part because of the high motivation for alcohol that humans exhibit and the hazardous binge intake this promotes. Orexin-1-type receptors (OX1Rs) promote reward intake under conditions of strong drives for reward, including excessive alcohol intake. While systemic modulation of OX1Rs can alter alcohol drinking, the brain regions that mediate this OX1R enhancement of excessive drinking remain unknown. Given the importance of the nucleus accumbens (NAc) and anterior insular cortex (aINS) in driving many addictive behaviors, including OX1Rs within these regions, we examined the importance of OX1Rs in these regions on excessive alcohol drinking in C57BL/6 mice during limited-access alcohol drinking in the dark cycle. Inhibition of OX1Rs with the widely used SB-334867 within the medial NAc Shell (mNAsh) significantly reduced drinking of alcohol, with no effect on saccharin intake, and no effect on alcohol consumption when infused above the mNAsh. In contrast, intra-mNAsh infusion of the orexin-2 receptor TCS-OX2-29 had no impact on alcohol drinking. In addition, OX1R inhibition within the aINS had no effect on excessive drinking, which was surprising given the importance of aINS-NAc circuits in promoting alcohol consumption and the role for aINS OX1Rs in driving nicotine intake. However, OX1R inhibition within the mPFC did reduce alcohol drinking, indicating cortical OXR involvement in promoting intake. Also, in support of the critical role for mNAsh OX1Rs, SB within the mNAsh also significantly reduced operant alcohol self-administration in rats. Finally, orexin ex vivo enhanced firing in mNAsh neurons from alcohol-drinking mice, with no effect on evoked EPSCs or input resistance; a similar orexin increase in firing without a change in input resistance was observed in alcohol-naïve mice. Taken together, our results suggest that OX1Rs within the mNAsh and mPFC, but not the aINS, play a central role in

  4. Heat shock transcription factor 1 promotes the proliferation, migration and invasion of osteosarcoma cells.

    PubMed

    Zhou, Zhenhua; Li, Yan; Jia, Qi; Wang, Zhiwei; Wang, Xudong; Hu, Jingjing; Xiao, Jianru

    2017-08-01

    Osteosarcoma is the most commonly diagnosed primary malignancy of bone and its overall survival rate is still very low. The molecular mechanisms underlying the progression of osteosarcoma have not been clearly illuminated. Heat shock transcription factor 1 (HSF1) is a key regulator of the heat shock response and also plays important roles in many cancers, but its function in osteosarcoma remains unexplored. In this study, the proliferation of osteosarcoma cells was determined by Cell Counting Kit-8 assays and colony formation assays. Transwell assays were used to demonstrate the migration and invasion abilities of osteosarcoma cells. A tumour formation assay in a nude mouse model was performed to assess the effect of HSF1 on osteosarcoma cell growth in vivo. The protein levels of HSF1 were analysed with immunohistochemical staining in samples from osteosarcoma patients. We demonstrated that knockdown of HSF1 reduced the proliferation, migration and invasion of osteosarcoma cells, while overexpression of HSF1 promoted the proliferation, migration and invasion of osteosarcoma cells. Furthermore, HSF1 promoted the proliferation of osteosarcoma cells in vivo. In addition, high levels of HSF1 were associated with a poor prognosis in osteosarcoma. These data highlight an important role of HSF1 in proliferation, migration and invasion of osteosarcoma cells. Moreover, the expression of HSF1 was associated with prognosis in osteosarcoma. © 2017 John Wiley & Sons Ltd.

  5. Endothelial cell SHP-2 negatively regulates neutrophil adhesion and promotes transmigration by enhancing ICAM-1-VE-cadherin interaction.

    PubMed

    Yan, Meiping; Zhang, Xinhua; Chen, Ao; Gu, Wei; Liu, Jie; Ren, Xiaojiao; Zhang, Jianping; Wu, Xiaoxiong; Place, Aaron T; Minshall, Richard D; Liu, Guoquan

    2017-11-01

    Intercellular adhesion molecule-1 (ICAM-1) mediates the firm adhesion of leukocytes to endothelial cells and initiates subsequent signaling that promotes their transendothelial migration (TEM). Vascular endothelial (VE)-cadherin plays a critical role in endothelial cell-cell adhesion, thereby controlling endothelial permeability and leukocyte transmigration. This study aimed to determine the molecular signaling events that originate from the ICAM-1-mediated firm adhesion of neutrophils that regulate VE-cadherin's role as a negative regulator of leukocyte transmigration. We observed that ICAM-1 interacts with Src homology domain 2-containing phosphatase-2 (SHP-2), and SHP-2 down-regulation via silencing of small interfering RNA in endothelial cells enhanced neutrophil adhesion to endothelial cells but inhibited neutrophil transmigration. We also found that VE-cadherin associated with the ICAM-1-SHP-2 complex. Moreover, whereas the activation of ICAM-1 leads to VE-cadherin dissociation from ICAM-1 and VE-cadherin association with actin, SHP-2 down-regulation prevented ICAM-1-VE-cadherin association and promoted VE-cadherin-actin association. Furthermore, SHP-2 down-regulation in vivo promoted LPS-induced neutrophil recruitment in mouse lung but delayed neutrophil extravasation. These results suggest that SHP-2- via association with ICAM-1-mediates ICAM-1-induced Src activation and modulates VE-cadherin switching association with ICAM-1 or actin, thereby negatively regulating neutrophil adhesion to endothelial cells and enhancing their TEM.-Yan, M., Zhang, X., Chen, A., Gu, W., Liu, J., Ren, X., Zhang, J., Wu, X., Place, A. T., Minshall, R. D., Liu, G. Endothelial cell SHP-2 negatively regulates neutrophil adhesion and promotes transmigration by enhancing ICAM-1-VE-cadherin interaction. © FASEB.

  6. M1-muscarinic receptors promote fear memory consolidation via phospholipase C and the M-current.

    PubMed

    Young, Matthew B; Thomas, Steven A

    2014-01-29

    Neuromodulators released during and after a fearful experience promote the consolidation of long-term memory for that experience. Because overconsolidation may contribute to the recurrent and intrusive memories of post-traumatic stress disorder, neuromodulatory receptors provide a potential pharmacological target for prevention. Stimulation of muscarinic receptors promotes memory consolidation in several conditioning paradigms, an effect primarily associated with the M1 receptor (M1R). However, neither inhibiting nor genetically disrupting M1R impairs the consolidation of cued fear memory. Using the M1R agonist cevimeline and antagonist telenzepine, as well as M1R knock-out mice, we show here that M1R, along with β2-adrenergic (β2AR) and D5-dopaminergic (D5R) receptors, regulates the consolidation of cued fear memory by redundantly activating phospholipase C (PLC) in the basolateral amygdala (BLA). We also demonstrate that fear memory consolidation in the BLA is mediated in part by neuromodulatory inhibition of the M-current, which is conducted by KCNQ channels and is known to be inhibited by muscarinic receptors. Manipulating the M-current by administering the KCNQ channel blocker XE991 or the KCNQ channel opener retigabine reverses the effects on consolidation caused by manipulating β2AR, D5R, M1R, and PLC. Finally, we show that cAMP and protein kinase A (cAMP/PKA) signaling relevant to this stage of consolidation is upstream of these neuromodulators and PLC, suggesting an important presynaptic role for cAMP/PKA in consolidation. These results support the idea that neuromodulatory regulation of ion channel activity and neuronal excitability is a critical mechanism for promoting consolidation well after acquisition has occurred.

  7. HTLV-1 Tax Stabilizes MCL-1 via TRAF6-Dependent K63-Linked Polyubiquitination to Promote Cell Survival and Transformation

    PubMed Central

    Choi, Young Bong; Harhaj, Edward William

    2014-01-01

    The human T-cell leukemia virus type 1 (HTLV-1) Tax protein hijacks the host ubiquitin machinery to activate IκB kinases (IKKs) and NF-κB and promote cell survival; however, the key ubiquitinated factors downstream of Tax involved in cell transformation are unknown. Using mass spectrometry, we undertook an unbiased proteome-wide quantitative survey of cellular proteins modified by ubiquitin in the presence of Tax or a Tax mutant impaired in IKK activation. Tax induced the ubiquitination of 22 cellular proteins, including the anti-apoptotic BCL-2 family member MCL-1, in an IKK-dependent manner. Tax was found to promote the nondegradative lysine 63 (K63)-linked polyubiquitination of MCL-1 that was dependent on the E3 ubiquitin ligase TRAF6 and the IKK complex. Tax interacted with and activated TRAF6, and triggered its mitochondrial localization, where it conjugated four carboxyl-terminal lysine residues of MCL-1 with K63-linked polyubiquitin chains, which stabilized and protected MCL-1 from genotoxic stress-induced degradation. TRAF6 and MCL-1 played essential roles in the survival of HTLV-1 transformed cells and the immortalization of primary T cells by HTLV-1. Therefore, K63-linked polyubiquitination represents a novel regulatory mechanism controlling MCL-1 stability that has been usurped by a viral oncogene to precipitate cell survival and transformation. PMID:25340740

  8. Cocaine promotes both initiation and elongation phase of HIV-1 transcription by activating NF-κB and MSK1 and inducing selective epigenetic modifications at HIV-1 LTR

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sahu, Geetaram; Farley, Kalamo; El-Hage, Nazira

    Cocaine accelerates human immunodeficiency virus (HIV-1) replication by altering specific cell-signaling and epigenetic pathways. We have elucidated the underlying molecular mechanisms through which cocaine exerts its effect in myeloid cells, a major target of HIV-1 in central nervous system (CNS). We demonstrate that cocaine treatment promotes HIV-1 gene expression by activating both nuclear factor-kappa B (NF-ĸB) and mitogen- and stress-activated kinase 1 (MSK1). MSK1 subsequently catalyzes the phosphorylation of histone H3 at serine 10, and p65 subunit of NF-ĸB at 276th serine residue. These modifications enhance the interaction of NF-ĸB with P300 and promote the recruitment of the positive transcriptionmore » elongation factor b (P-TEFb) to the HIV-1 LTR, supporting the development of an open/relaxed chromatin configuration, and facilitating the initiation and elongation phases of HIV-1 transcription. Results are also confirmed in primary monocyte derived macrophages (MDM). Overall, our study provides detailed insights into cocaine-driven HIV-1 transcription and replication. - Highlights: • Cocaine induces the initiation phase of HIV transcription by activating NF-ĸB. • Cocaine induced NF-ĸB phosphorylation promotes its interaction with P300. • Cocaine enhances the elongation phase of HIV transcription by stimulating MSK1. • Cocaine activated MSK1 catalyzes the phosphorylation of histone H3 at its Ser10. • Cocaine induced H3S10 phosphorylation facilitates the recruitment of P-TEFb at LTR.« less

  9. Health promoting schools.

    PubMed

    1998-01-01

    Promoting the health of children through schools has long been an important task of the WHO. Guided by the recommendations of the Expert Committee on Comprehensive School Health Education and Promotion, the Initiative seeks to strengthen health promotion and education activities at the local, national, regional, and global levels. It aims to increase the number of schools that can truly be called "Health-Promoting Schools". The four strategies undertaken by WHO in creating Health-Promoting Schools are: 1) strengthening the ability to advocate for improved school health programs, 2) creating networks and alliances for the development of Health-Promoting Schools, 3) strengthening national capacities, and 4) research to improve school health program. Finally, WHO recognizes that the success of the Global School Health Initiative lies on the extent to which partnerships can be formed at local, national, and international levels.

  10. Functional Incompatibility between the Generic NF-κB Motif and a Subtype-Specific Sp1III Element Drives the Formation of the HIV-1 Subtype C Viral Promoter

    PubMed Central

    Verma, Anjali; Rajagopalan, Pavithra; Lotke, Rishikesh; Varghese, Rebu; Selvam, Deepak; Kundu, Tapas K.

    2016-01-01

    ABSTRACT Of the various genetic subtypes of human immunodeficiency virus types 1 and 2 (HIV-1 and HIV-2) and simian immunodeficiency virus (SIV), only in subtype C of HIV-1 is a genetically variant NF-κB binding site found at the core of the viral promoter in association with a subtype-specific Sp1III motif. How the subtype-associated variations in the core transcription factor binding sites (TFBS) influence gene expression from the viral promoter has not been examined previously. Using panels of infectious viral molecular clones, we demonstrate that subtype-specific NF-κB and Sp1III motifs have evolved for optimal gene expression, and neither of the motifs can be replaced by a corresponding TFBS variant. The variant NF-κB motif binds NF-κB with an affinity 2-fold higher than that of the generic NF-κB site. Importantly, in the context of an infectious virus, the subtype-specific Sp1III motif demonstrates a profound loss of function in association with the generic NF-κB motif. An additional substitution of the Sp1III motif fully restores viral replication, suggesting that the subtype C-specific Sp1III has evolved to function with the variant, but not generic, NF-κB motif. A change of only two base pairs in the central NF-κB motif completely suppresses viral transcription from the provirus and converts the promoter into heterochromatin refractory to tumor necrosis factor alpha (TNF-α) induction. The present work represents the first demonstration of functional incompatibility between an otherwise functional NF-κB motif and a unique Sp1 site in the context of an HIV-1 promoter. Our work provides important leads as to the evolution of the HIV-1 subtype C viral promoter with relevance for gene expression regulation and viral latency. IMPORTANCE Subtype-specific genetic variations provide a powerful tool to examine how these variations offer a replication advantage to specific viral subtypes, if any. Only in subtype C of HIV-1 are two genetically distinct

  11. Tumor-extrinsic discoidin domain receptor 1 promotes mammary tumor growth by regulating adipose stromal interleukin 6 production in mice.

    PubMed

    Sun, Xiujie; Gupta, Kshama; Wu, Bogang; Zhang, Deyi; Yuan, Bin; Zhang, Xiaowen; Chiang, Huai-Chin; Zhang, Chi; Curiel, Tyler J; Bendeck, Michelle P; Hursting, Stephen; Hu, Yanfen; Li, Rong

    2018-02-23

    Discoidin domain receptor 1 (DDR1) is a collagen receptor that mediates cell communication with the extracellular matrix (ECM). Aberrant expression and activity of DDR1 in tumor cells are known to promote tumor growth. Although elevated DDR1 levels in the stroma of breast tumors are associated with poor patient outcome, a causal role for tumor-extrinsic DDR1 in cancer promotion remains unclear. Here we report that murine mammary tumor cells transplanted to syngeneic recipient mice in which Ddr1 has been knocked out (KO) grow less robustly than in WT mice. We also found that the tumor-associated stroma in Ddr1- KO mice exhibits reduced collagen deposition compared with the WT controls, supporting a role for stromal DDR1 in ECM remodeling of the tumor microenvironment. Furthermore, the stromal-vascular fraction (SVF) of Ddr1 knockout adipose tissue, which contains committed adipose stem/progenitor cells and preadipocytes, was impaired in its ability to stimulate tumor cell migration and invasion. Cytokine array-based screening identified interleukin 6 (IL-6) as a cytokine secreted by the SVF in a DDR1-dependent manner. SVF-produced IL-6 is important for SVF-stimulated tumor cell invasion in vitro , and, using antibody-based neutralization, we show that tumor promotion by IL-6 in vivo requires DDR1. In conclusion, our work demonstrates a previously unrecognized function of DDR1 in promoting tumor growth. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

  12. Heteroduplex DNA Position Defines the Roles of the Sgs1, Srs2, and Mph1 Helicases in Promoting Distinct Recombination Outcomes

    PubMed Central

    Mitchel, Katrina; Lehner, Kevin; Jinks-Robertson, Sue

    2013-01-01

    The contributions of the Sgs1, Mph1, and Srs2 DNA helicases during mitotic double-strand break (DSB) repair in yeast were investigated using a gap-repair assay. A diverged chromosomal substrate was used as a repair template for the gapped plasmid, allowing mismatch-containing heteroduplex DNA (hDNA) formed during recombination to be monitored. Overall DSB repair efficiencies and the proportions of crossovers (COs) versus noncrossovers (NCOs) were determined in wild-type and helicase-defective strains, allowing the efficiency of CO and NCO production in each background to be calculated. In addition, the products of individual NCO events were sequenced to determine the location of hDNA. Because hDNA position is expected to differ depending on whether a NCO is produced by synthesis-dependent-strand-annealing (SDSA) or through a Holliday junction (HJ)–containing intermediate, its position allows the underlying molecular mechanism to be inferred. Results demonstrate that each helicase reduces the proportion of CO recombinants, but that each does so in a fundamentally different way. Mph1 does not affect the overall efficiency of gap repair, and its loss alters the CO-NCO by promoting SDSA at the expense of HJ–containing intermediates. By contrast, Sgs1 and Srs2 are each required for efficient gap repair, strongly promoting NCO formation and having little effect on CO efficiency. hDNA analyses suggest that all three helicases promote SDSA, and that Sgs1 and Srs2 additionally dismantle HJ–containing intermediates. The hDNA data are consistent with the proposed role of Sgs1 in the dissolution of double HJs, and we propose that Srs2 dismantles nicked HJs. PMID:23516370

  13. De novo disruption of promoter and exon 1 of STAR gene reveals essential role for gonadal development.

    PubMed

    Piya, Anil; Kaur, Jasmeet; Rice, Alan M; Bose, Himangshu S

    2017-01-01

    Cholesterol transport into the mitochondria is required for synthesis of the first steroid, pregnenolone. Cholesterol is transported by the steroidogenic acute regulatory protein (STAR), which acts at the outer mitochondrial membrane prior to its import. Mutations in the STAR protein result in lipoid congenital adrenal hyperplasia (CAH). Although the STAR protein consists of seven exons, biochemical analysis in nonsteroidogenic COS-1 cells showed that the first two were not essential for pregnenolone synthesis. Here, we present a patient with ambiguous genitalia, salt-lossing crisis within two weeks after birth and low cortisol levels. Sequence analysis of the STAR , including the exon-intron boundaries, showed the complete deletion of exon 1 as well as more than 50 nucleotides upstream of STAR promoter. Mitochondrial protein import with the translated protein through synthesis cassette of the mutant STAR lacking exon 1 showed protein translation, but it is less likely to have synthesized without a promoter in our patient. Thus, a full-length STAR gene is necessary for physiological mitochondrial cholesterol transport in vivo . STAR exon 1 deletion caused lipoid CAH.Exon 1 substitution does not affect biochemical activity.StAR promoter is responsible for gonadal development.

  14. De novo disruption of promoter and exon 1 of STAR gene reveals essential role for gonadal development

    PubMed Central

    Piya, Anil; Kaur, Jasmeet; Rice, Alan M

    2017-01-01

    Summary Cholesterol transport into the mitochondria is required for synthesis of the first steroid, pregnenolone. Cholesterol is transported by the steroidogenic acute regulatory protein (STAR), which acts at the outer mitochondrial membrane prior to its import. Mutations in the STAR protein result in lipoid congenital adrenal hyperplasia (CAH). Although the STAR protein consists of seven exons, biochemical analysis in nonsteroidogenic COS-1 cells showed that the first two were not essential for pregnenolone synthesis. Here, we present a patient with ambiguous genitalia, salt-lossing crisis within two weeks after birth and low cortisol levels. Sequence analysis of the STAR, including the exon–intron boundaries, showed the complete deletion of exon 1 as well as more than 50 nucleotides upstream of STAR promoter. Mitochondrial protein import with the translated protein through synthesis cassette of the mutant STAR lacking exon 1 showed protein translation, but it is less likely to have synthesized without a promoter in our patient. Thus, a full-length STAR gene is necessary for physiological mitochondrial cholesterol transport in vivo. Learning points: STAR exon 1 deletion caused lipoid CAH. Exon 1 substitution does not affect biochemical activity. StAR promoter is responsible for gonadal development. PMID:28458886

  15. The relationship between RASSF1A promoter methylation and thyroid carcinoma: A meta-analysis of 14 articles and a bioinformatics of 2 databases (PRISMA).

    PubMed

    Niu, Heng; Yang, Jingyu; Yang, Kunxian; Huang, Yingze

    2017-11-01

    DNA promoter methylation can suppresses gene expression and shows an important role in the biological functions of Ras association domain family 1A (RASSF1A). Many studies have performed to elucidate the role of RASSF1A promoter methylation in thyroid carcinoma, while the results were conflicting and heterogeneous. Here, we analyzed the data of databases to determine the relationship between RASSF1A promoter methylation and thyroid carcinoma. We used the data from 14 cancer-normal studies and Gene Expression Omnibus (GEO) database to analyze RASSF1A promoter methylation in thyroid carcinoma susceptibility. The data from the Cancer Genome Atlas project (TCGA) database was used to analyze the relationship between RASSF1A promoter methylation and thyroid carcinoma susceptibility, clinical characteristics, prognosis. Odds ratios were estimated for thyroid carcinoma susceptibility and hazard ratios were estimated for thyroid carcinoma prognosis. The heterogeneity between studies of meta-analysis was explored using H, I values, and meta-regression. We adopted quality criteria to classify the studies of meta-analysis. Subgroup analyses were done for thyroid carcinoma susceptibility according to ethnicity, methods, and primers. Result of meta-analysis indicated that RASSF1A promoter methylation is associated with higher susceptibility to thyroid carcinoma with small heterogeneity. Similarly, the result from GEO database also showed that a significant association between RASSF1A gene promoter methylation and thyroid carcinoma susceptibility. For the results of TCGA database, we found that RASSF1A promoter methylation is associated with susceptibility and poor disease-free survival (DFS) of thyroid carcinoma. In addition, we also found a close association between RASSF1A promoter methylation and patient tumor stage and age, but not in patients of different genders. The methylation status of RASSF1A promoter is strongly associated with thyroid carcinoma susceptibility and DFS

  16. JunD/AP-1 Antagonizes the Induction of DAPK1 To Promote the Survival of v-Src-Transformed Cells.

    PubMed

    Maślikowski, Bart M; Wang, Lizhen; Wu, Ying; Fielding, Ben; Bédard, Pierre-André

    2017-01-01

    The increase in AP-1 activity is a hallmark of cell transformation by tyrosine kinases. Previously, we reported that blocking AP-1 using the c-Jun dominant negative mutant TAM67 induced senescence, adipogenesis, or apoptosis in v-Src-transformed chicken embryo fibroblasts (CEFs) whereas inhibition of JunD by short hairpin RNA (shRNA) specifically induced apoptosis. To investigate the role of AP-1 in Src-mediated transformation, we undertook a gene profiling study to characterize the transcriptomes of v-Src-transformed CEFs expressing either TAM67 or the JunD shRNA. Our study revealed a cluster of 18 probe sets upregulated exclusively in response to AP-1/JunD impairment and v-Src transformation. Four of these probe sets correspond to genes involved in the interferon pathway. One gene in particular, death-associated protein kinase 1 (DAPK1), is a C/EBPβ-regulated mediator of apoptosis in gamma interferon (IFN-γ)-induced cell death. Here, we show that inhibition of DAPK1 abrogates cell death in v-Src-transformed cells expressing the JunD shRNA. Chromatin immunoprecipitation data indicated that C/EBPβ was recruited to the DAPK1 promoter while the expression of a dominant negative mutant of C/EBPβ abrogated the induction of DAPK1 in response to the inhibition of AP-1. In contrast, as determined by chromatin immunoprecipitation (ChIP) assays, JunD was not detected on the DAPK1 promoter under any conditions, suggesting that JunD promotes survival by indirectly antagonizing the expression of DAPK1 in v-Src transformed cells. Transformation by the v-Src oncoprotein causes extensive changes in gene expression in primary cells such as chicken embryo fibroblasts. These changes, determining the properties of transformed cells, are controlled in part at the transcriptional level. Much attention has been devoted to transcription factors such as AP-1 and NF-κB and the control of genes associated with a more aggressive phenotype. In this report, we describe a novel mechanism

  17. Tobacco Translationally Controlled Tumor Protein Interacts with Ethylene Receptor Tobacco Histidine Kinase1 and Enhances Plant Growth through Promotion of Cell Proliferation1[OPEN

    PubMed Central

    Tao, Jian-Jun; Cao, Yang-Rong; Chen, Hao-Wei; Wei, Wei; Li, Qing-Tian; Ma, Biao; Zhang, Wan-Ke; Chen, Shou-Yi; Zhang, Jin-Song

    2015-01-01

    Ethylene is an important phytohormone in the regulation of plant growth, development, and stress response throughout the lifecycle. Previously, we discovered that a subfamily II ethylene receptor tobacco (Nicotiana tabacum) Histidine Kinase1 (NTHK1) promotes seedling growth. Here, we identified an NTHK1-interacting protein translationally controlled tumor protein (NtTCTP) by the yeast (Saccharomyces cerevisiae) two-hybrid assay and further characterized its roles in plant growth. The interaction was further confirmed by in vitro glutathione S-transferase pull down and in vivo coimmunoprecipitation and bimolecular fluorescence complementation assays, and the kinase domain of NTHK1 mediates the interaction with NtTCTP. The NtTCTP protein is induced by ethylene treatment and colocalizes with NTHK1 at the endoplasmic reticulum. Overexpression of NtTCTP or NTHK1 reduces plant response to ethylene and promotes seedling growth, mainly through acceleration of cell proliferation. Genetic analysis suggests that NtTCTP is required for the function of NTHK1. Furthermore, association of NtTCTP prevents NTHK1 from proteasome-mediated protein degradation. Our data suggest that plant growth inhibition triggered by ethylene is regulated by a unique feedback mechanism, in which ethylene-induced NtTCTP associates with and stabilizes ethylene receptor NTHK1 to reduce plant response to ethylene and promote plant growth through acceleration of cell proliferation. PMID:25941315

  18. Rb1 haploinsufficiency promotes telomere attrition and radiation-induced genomic instability.

    PubMed

    Gonzalez-Vasconcellos, Iria; Anastasov, Natasa; Sanli-Bonazzi, Bahar; Klymenko, Olena; Atkinson, Michael J; Rosemann, Michael

    2013-07-15

    Germline mutations of the retinoblastoma gene (RB1) predispose to both sporadic and radiation-induced osteosarcoma, tumors characterized by high levels of genomic instability, and activation of alternative lengthening of telomeres. Mice with haploinsufficiency of the Rb1 gene in the osteoblastic lineage reiterate the radiation susceptibility to osteosarcoma seen in patients with germline RB1 mutations. We show that the susceptibility is accompanied by an increase in genomic instability, resulting from Rb1-dependent telomere erosion. Radiation exposure did not accelerate the rate of telomere loss but amplified the genomic instability resulting from the dysfunctional telomeres. These findings suggest that telomere maintenance is a noncanonical caretaker function of the retinoblastoma protein, such that its deficiency in cancer may potentiate DNA damage-induced carcinogenesis by promoting formation of chromosomal aberrations, rather than simply by affecting cell-cycle control. ©2013 AACR.

  19. Sebacina vermifera Promotes the Growth and Fitness of Nicotiana attenuata by Inhibiting Ethylene Signaling1[W

    PubMed Central

    Barazani, Oz; von Dahl, Caroline C.; Baldwin, Ian T.

    2007-01-01

    Sebacina vermifera, a growth-promoting endophytic fungus, significantly increases Nicotiana attenuata's growth but impairs both its herbivore resistance and its accumulation of the costly, jasmonic acid (JA)-regulated defense protein, trypsin proteinase inhibitor (TPI). To determine if the fungi's growth-promoting effects can be attributed to lower TPI-related defense costs, we inoculated transformed N. attenuata plants silenced in their ability to synthesize JA, JA-isoleucine, and TPI by antisense (lipoxygenase 3 [as-lox3] and Thr deaminase [as-td]) and inverted repeat (ir-tpi) expression, and found that inoculation promoted plant growth as in untransformed wild-type plants. Moreover, herbivore-elicited increases in JA and JA-isoleucine concentrations did not differ between inoculated and uninoculated wild-type plants. However, inoculation significantly reduced the morphological effect of 1-aminocyclopropane-1-carboxylic acid on wild-type seedlings in a triple response assay, suggesting that ethylene signaling was impaired. Furthermore, S. vermifera failed to promote the growth of N. attenuata plants transformed to silence ethylene production (1-aminocyclopropane-1-carboxylic acid oxidase [ir-aco]). Inoculating wild-type plants with S. vermifera decreased the ethylene burst elicited by applying Manduca sexta oral secretions to mechanical wounds. Accordingly, oral secretion-elicited transcript levels of the ethylene synthesis genes NaACS3, NaACO1, and NaACO3 in inoculated plants were significantly lower compared to these levels in uninoculated wild-type plants. Inoculation accelerated germination in wild-type seeds; however, uninoculated wild-type seeds germinated as rapidly as inoculated seeds in the presence of the ethylene scrubber KMnO4. In contrast, neither inoculation nor KMnO4 exposure influenced the germination of ir-aco seeds. We conclude that S. vermifera increases plant growth by impairing ethylene production independently of JA signaling and TPI

  20. Ciliary dyslexia candidate genes DYX1C1 and DCDC2 are regulated by Regulatory Factor X (RFX) transcription factors through X-box promoter motifs

    PubMed Central

    Tammimies, Kristiina; Bieder, Andrea; Lauter, Gilbert; Sugiaman-Trapman, Debora; Torchet, Rachel; Hokkanen, Marie-Estelle; Burghoorn, Jan; Castrén, Eero; Kere, Juha; Tapia-Páez, Isabel; Swoboda, Peter

    2016-01-01

    DYX1C1, DCDC2, and KIAA0319 are three of the most replicated dyslexia candidate genes (DCGs). Recently, these DCGs were implicated in functions at the cilium. Here, we investigate the regulation of these DCGs by Regulatory Factor X transcription factors (RFX TFs), a gene family known for transcriptionally regulating ciliary genes. We identify conserved X-box motifs in the promoter regions of DYX1C1, DCDC2, and KIAA0319 and demonstrate their functionality, as well as the ability to recruit RFX TFs using reporter gene and electrophoretic mobility shift assays. Furthermore, we uncover a complex regulation pattern between RFX1, RFX2, and RFX3 and their significant effect on modifying the endogenous expression of DYX1C1 and DCDC2 in a human retinal pigmented epithelial cell line immortalized with hTERT (hTERT-RPE1). In addition, induction of ciliogenesis increases the expression of RFX TFs and DCGs. At the protein level, we show that endogenous DYX1C1 localizes to the base of the cilium, whereas DCDC2 localizes along the entire axoneme of the cilium, thereby validating earlier localization studies using overexpression models. Our results corroborate the emerging role of DCGs in ciliary function and characterize functional noncoding elements, X-box promoter motifs, in DCG promoter regions, which thus can be targeted for mutation screening in dyslexia and ciliopathies associated with these genes.—Tammimies, K., Bieder, A., Lauter, G., Sugiaman-Trapman, D., Torchet, R., Hokkanen, M.-E., Burghoorn, J., Castrén, E., Kere, J., Tapia-Páez, I., Swoboda, P. Ciliary dyslexia candidate genes DYX1C1 and DCDC2 are regulated by Regulatory Factor (RF) X transcription factors through X-box promoter motifs. PMID:27451412