Nectin-like molecule 1 inhibits the migration and invasion of U251 glioma cells by regulating the expression of an extracellular matrix protein osteopontin.

PubMed

Yin, Bin; Li, Ke-han; An, Tai; Chen, Tao; Peng, Xiao-zhong

2010-06-01

To investigate the molecular mechanism of nectin-like molecule 1 (NECL1) inhibiting the migration and invasion of U251 glioma cells. We infected U251 glioma cells with adeno-nectin-like molecule 1 (Ad-NECL1) or empty adenovirus (Ad). Transwell and wound healing assays were performed to observe the migration of U251 cells incubated with the cell supernatant from Ad-NECL1 or Ad infected U251 cells. DNA microarray was applied to screen the gene expression profile after the restoration of NECL1 in U251 glioma cell lines. The differential expression of osteopontin (OPN), a gene related to migration and invasion, was further analyzed with semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR), Western blot, and immunohistochemistry. The restoration of NECL1 inhibited migration of U251 cells significantly (P<0.05). Altogether 195 genes were found differentially expressed by microarray, in which 175 were up-regulated and 20 down-regulated, including 9 extracellular matrix proteins involved in the migration of cells. Both mRNA and protein expressions of OPN, the most markedly reduced extracellular matrix protein, were found decreased in U251 cells after restoration of NECL1. Immunohistochemical assay also detected an increase of OPN in glioma tissues, related with the progressing of malignant grade. A link might exist between NECL1 and the extracellular matrix protein OPN in inhibiting the migration and invasion of U251 glioma cells.

Neural cell adhesion molecule-deficient beta-cell tumorigenesis results in diminished extracellular matrix molecule expression and tumour cell-matrix adhesion.

PubMed

Håkansson, Joakim; Xian, Xiaojie; He, Liqun; Ståhlberg, Anders; Nelander, Sven; Samuelsson, Tore; Kubista, Mikael; Semb, Henrik

2005-01-01

To understand by which mechanism neural cell adhesion molecule (N-CAM) limits beta tumour cell disaggregation and dissemination, we searched for potential downstream genes of N-CAM during beta tumour cell progression by gene expression profiling. Here, we show that N-CAM-deficient beta-cell tumorigenesis is associated with changes in the expression of genes involved in cell-matrix adhesion and cytoskeletal dynamics, biological processes known to affect the invasive and metastatic behaviour of tumour cells. The extracellular matrix (ECM) molecules emerged as the primary target, i.e. N-CAM deficiency resulted in down-regulated mRNA expression of a broad range of ECM molecules. Consistent with this result, deficient deposition of major ECM stromal components, such as fibronectin, laminin 1 and collagen IV, was observed. Moreover, N-CAM-deficient tumour cells displayed defective matrix adhesion. These results offer a potential mechanism for tumour cell disaggregation during N-CAM-deficient beta tumour cell progression. Prospective consequences of these findings for the role of N-CAM in beta tumour cell dissemination are discussed.

LINE1 family member is negative regulator of HLA-G expression.

PubMed

Ikeno, Masashi; Suzuki, Nobutaka; Kamiya, Megumi; Takahashi, Yuji; Kudoh, Jun; Okazaki, Tsuneko

2012-11-01

Class Ia molecules of human leucocyte antigen (HLA-A, -B and -C) are widely expressed and play a central role in the immune system by presenting peptides derived from the lumen of the endoplasmic reticulum. In contrast, class Ib molecules such as HLA-G serve novel functions. The distribution of HLA-G is mostly limited to foetal trophoblastic tissues and some tumour tissues. The mechanism required for the tissue-specific regulation of the HLA-G gene has not been well understood. Here, we investigated the genomic regulation of HLA-G by manipulating one copy of a genomic DNA fragment on a human artificial chromosome. We identified a potential negative regulator of gene expression in a sequence upstream of HLA-G that overlapped with the long interspersed element (LINE1); silencing of HLA-G involved a DNA secondary structure generated in LINE1. The presence of a LINE1 gene silencer may explain the limited expression of HLA-G compared with other class I genes.

Lymphatic function is regulated by a coordinated expression of lymphangiogenic and anti-lymphangiogenic cytokines

PubMed Central

Zampell, Jamie C.; Avraham, Tomer; Yoder, Nicole; Fort, Nicholas; Yan, Alan; Weitman, Evan S.

2012-01-01

Lymphangiogenic cytokines such as vascular endothelial growth factor-C (VEGF-C) are critically required for lymphatic regeneration; however, in some circumstances, lymphatic function is impaired despite normal or elevated levels of these cytokines. The recent identification of anti-lymphangiogenic molecules such as interferon-γ (IFN-γ), transforming growth factor-β1, and endostatin has led us to hypothesize that impaired lymphatic function may represent a dysregulated balance in the expression of pro/anti-lymphangiogenic stimuli. We observed that nude mice have significantly improved lymphatic function compared with wild-type mice in a tail model of lymphedema. We show that gradients of lymphatic fluid stasis regulate the expression of lymphangiogenic cytokines (VEGF-A, VEGF-C, and hepatocyte growth factor) and that paradoxically the expression of these molecules is increased in wild-type mice. More importantly, we show that as a consequence of T-cell-mediated inflammation, these same gradients also regulate expression patterns of anti-lymphangiogenic molecules corresponding temporally and spatially with impaired lymphatic function in wild-type mice. We show that neutralization of IFN-γ significantly increases inflammatory lymph node lymphangiogenesis independently of changes in VEGF-A or VEGF-C expression, suggesting that alterations in the balance of pro- and anti-lymphangiogenic cytokine expression can regulate lymphatic vessel formation. In conclusion, we show that gradients of lymphatic fluid stasis regulate not only the expression of pro-lymphangiogenic cytokines but also potent suppressors of lymphangiogenesis as a consequence of T-cell inflammation and that modulation of the balance between these stimuli can regulate lymphatic function. PMID:21940662

Dragon (repulsive guidance molecule b) inhibits IL-6 expression in macrophages.

PubMed

Xia, Yin; Cortez-Retamozo, Virna; Niederkofler, Vera; Salie, Rishard; Chen, Shanzhuo; Samad, Tarek A; Hong, Charles C; Arber, Silvia; Vyas, Jatin M; Weissleder, Ralph; Pittet, Mikael J; Lin, Herbert Y

2011-02-01

Repulsive guidance molecule (RGM) family members RGMa, RGMb/Dragon, and RGMc/hemojuvelin were found recently to act as bone morphogenetic protein (BMP) coreceptors that enhance BMP signaling activity. Although our previous studies have shown that hemojuvelin regulates hepcidin expression and iron metabolism through the BMP pathway, the role of the BMP signaling mediated by Dragon remains largely unknown. We have shown previously that Dragon is expressed in neural cells, germ cells, and renal epithelial cells. In this study, we demonstrate that Dragon is highly expressed in macrophages. Studies with RAW264.7 and J774 macrophage cell lines reveal that Dragon negatively regulates IL-6 expression in a BMP ligand-dependent manner via the p38 MAPK and Erk1/2 pathways but not the Smad1/5/8 pathway. We also generated Dragon knockout mice and found that IL-6 is upregulated in macrophages and dendritic cells derived from whole lung tissue of these mice compared with that in respective cells derived from wild-type littermates. These results indicate that Dragon is an important negative regulator of IL-6 expression in immune cells and that Dragon-deficient mice may be a useful model for studying immune and inflammatory disorders.

A tetracycline inducible expression vector for Corynebacterium glutamicum allowing tightly regulable gene expression.

PubMed

Lausberg, Frank; Chattopadhyay, Ava Rebecca; Heyer, Antonia; Eggeling, Lothar; Freudl, Roland

2012-09-01

Here we report on the construction of a tetracycline inducible expression vector that allows a tightly regulable gene expression in Corynebacterium glutamicum which is used in industry for production of small molecules such as amino acids. Using the green fluorescent protein (GFP) as a reporter protein we show that this vector, named pCLTON1, is characterized by tight repression under non-induced conditions as compared to a conventional IPTG inducible expression vector, and that it allows gradual GFP synthesis upon gradual increase of anhydrotetracycline addition. Copyright © 2012 Elsevier Inc. All rights reserved.

Highly sensitivity adhesion molecules detection in hereditary haemochromatosis patients reveals altered expression.

PubMed

Norris, S; White, M; Mankan, A K; Lawless, M W

2010-04-01

Several abnormalities in the immune status of patients with hereditary haemochromatosis (HH) have been reported, suggesting an imbalance in their immune function. This may include persistent production of, or exposure to, altered immune signalling contributing to the pathogenesis of this disorder. Adhesion molecules L-, E- and P-Selectin, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) are some of the major regulators of the immune processes and altered levels of these proteins have been found in pathological states including cardiovascular diseases, arthritis and liver cancer. The aim of this study was to assess L-, E- and P-Selectin, ICAM-1 and VCAM-1 expression in patients with HH and correlate these results with HFE mutation status and iron indexes. A total of 139 subjects were diagnosed with HH (C282Y homozygotes = 87, C282Y/H63D = 26 heterozygotes, H63D homozygotes = 26), 27 healthy control subjects with no HFE mutation (N/N), 18 normal subjects heterozygous for the H63D mutation served as age-sex-matched controls. We observed a significant decrease in L-selectin (P = 0.0002) and increased E-selectin and ICAM-1 (P = 0.0006 and P = 0.0059) expression in HH patients compared with healthy controls. This study observes for the first time that an altered adhesion molecules profile occurs in patients with HH that is associated with specific HFE genetic component for iron overload, suggesting that differential expression of adhesion molecules may play a role in the pathogenesis of HH.

Sarcoptes scabiei (Acari: Sarcoptidae) Mite Extract Modulates Expression of Cytokines and Adhesion Molecules by Human Dermal Microvascular Endothelial Cells.

PubMed Central

Elder, B. Laurel; Arlian, Larry G.; Morgan, Marjorie S.

2007-01-01

The inflammatory and immune responses seen with the worldwide disease scabies (caused by the mite Sarcoptes scabiei) are complex. Clinical symptoms are delayed for weeks in patients when they are infested with scabies for the first time. This study was undertaken to elucidate the role of the human dermal microvascular endothelial cell (HMVEC-D) in modulating the inflammatory and immune responses in the skin to S. scabiei. Extracts of S. scabiei were incubated with HMVEC-D and the expression of adhesion molecules and chemokine receptors on the cells and the secretion of selected cytokines were determined by ELISA. S. scabiei extract was found to inhibit HMVEC-D expression of E-selectin and vascular cell adhesion molecule-1 (VCAM-1) although not intercellular adhesion molecule-1 (ICAM-1). The secretion of interleukin-8 (IL-8) was also inhibited by S. scabiei extract. S. scabiei extract increased expression of the chemokine receptor CXCR-1, and both down-regulated and up-regulated expression of CXCR-2 depending on the concentration tested. These findings help explain the delayed inflammatory reaction to infestation with S. scabiei. PMID:17017228

Regulated necrosis-related molecule mRNA expression in humans and mice and in murine acute tissue injury and systemic autoimmunity leading to progressive organ damage, and progressive fibrosis.

PubMed

Honarpisheh, Mohsen; Desai, Jyaysi; Marschner, Julian A; Weidenbusch, Marc; Lech, Maciej; Vielhauer, Volker; Anders, Hans-Joachim; Mulay, Shrikant R

2016-12-01

The species-specific, as well as organ-specific expression of regulated necrosis (RN)-related molecules, is not known. We determined the expression levels of tumour necrosis factor receptor-1 (TNFR1), receptor activated protein kinase (RIPK)1, RIPK3, mixed lineage kinase domain-like (MLKL), CASP8, Fas-associated protein with death domain (FADD), cellular inhibitor of apoptosis protein (CIAP)1, CIAP2, glutathione peroxidase-4 (GPX4), cyclophilin D (CYPD), CASP1, NLRP3 and poly(ADP-ribose) polymerase-1 (PARP1) in human and mouse solid organs. We observed significant differences in expression of these molecules between human and mice. In addition, we characterized their expression profiles in acute as well as persistent tissue injury and chronic tissue remodelling using acute and chronic kidney injury models. We observed that the degree and pattern of induction of RN-related molecules were highly dependent on the trigger and disease pathogenesis. Furthermore, we studied their expression patterns in mice with lupus-like systemic autoimmunity, which revealed that the expression of MLKL, GPX4 and PARP1 significantly increased in the spleen along disease progression and CASP1, RIPK1, RIPK3 and CYPD were higher at the earlier stages but were significantly decreased in the later stages. In contrast, in the kidney, the expression of genes involved in pyroptosis, e.g. NLRP3 and CASP1 were significantly increased and TNFR1, RIPK1, RIPK3, CIAP1/2 and GPX4 were significantly decreased along the progression of lupus nephritis (LN). Thus, the organ- and species-specific expression of RN-related molecules should be considered during designing experiments, interpreting the results as well as extrapolating the conclusions from one species or organ to another species or organ respectively. © 2016 The Author(s).

Regulated necrosis-related molecule mRNA expression in humans and mice and in murine acute tissue injury and systemic autoimmunity leading to progressive organ damage, and progressive fibrosis

PubMed Central

Honarpisheh, Mohsen; Desai, Jyaysi; Marschner, Julian A.; Weidenbusch, Marc; Lech, Maciej; Vielhauer, Volker; Anders, Hans-Joachim; Mulay, Shrikant R.

2016-01-01

The species-specific, as well as organ-specific expression of regulated necrosis (RN)-related molecules, is not known. We determined the expression levels of tumour necrosis factor receptor-1 (TNFR1), receptor activated protein kinase (RIPK)1, RIPK3, mixed lineage kinase domain-like (MLKL), CASP8, Fas-associated protein with death domain (FADD), cellular inhibitor of apoptosis protein (CIAP)1, CIAP2, glutathione peroxidase-4 (GPX4), cyclophilin D (CYPD), CASP1, NLRP3 and poly(ADP-ribose) polymerase-1 (PARP1) in human and mouse solid organs. We observed significant differences in expression of these molecules between human and mice. In addition, we characterized their expression profiles in acute as well as persistent tissue injury and chronic tissue remodelling using acute and chronic kidney injury models. We observed that the degree and pattern of induction of RN-related molecules were highly dependent on the trigger and disease pathogenesis. Furthermore, we studied their expression patterns in mice with lupus-like systemic autoimmunity, which revealed that the expression of MLKL, GPX4 and PARP1 significantly increased in the spleen along disease progression and CASP1, RIPK1, RIPK3 and CYPD were higher at the earlier stages but were significantly decreased in the later stages. In contrast, in the kidney, the expression of genes involved in pyroptosis, e.g. NLRP3 and CASP1 were significantly increased and TNFR1, RIPK1, RIPK3, CIAP1/2 and GPX4 were significantly decreased along the progression of lupus nephritis (LN). Thus, the organ- and species-specific expression of RN-related molecules should be considered during designing experiments, interpreting the results as well as extrapolating the conclusions from one species or organ to another species or organ respectively. PMID:27811014

Stimulation of nuclear receptor REV-ERBs regulates tumor necrosis factor-induced expression of proinflammatory molecules in C6 astroglial cells

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

Morioka, Norimitsu, E-mail: mnori@hiroshima-u.ac.jp; Tomori, Mizuki; Zhang, Fang Fang

Under physiological conditions, astrocytes maintain homeostasis in the CNS. Following inflammation and injury to the CNS, however, activated astrocytes produce neurotoxic molecules such as cytokines and chemokines, amplifying the initial molecular-cellular events evoked by inflammation and injury. Nuclear receptors REV-ERBα and REV-ERBβ (REV-ERBs) are crucial in the regulation of inflammation- and metabolism-related gene transcription. The current study sought to elucidate a role of REV-ERBs in rat C6 astroglial cells on the expression of inflammatory molecules following stimulation with the neuroinflammatory cytokine tumor necrosis factor (TNF). Stimulation of C6 cells with TNF (10 ng/ml) significantly increased the mRNA expression of CCL2, interleukin-6more » (IL-6), inducible nitric oxide synthase (iNOS), and matrix metalloprotease (MMP)-9, but not fibroblast growth factor-2 (FGF-2), cyclooxygenase-2 (COX-2) and MMP-2. Treatment with either REV-ERB agonists GSK4112 or SR9009 significantly blocked TNF-induced upregulation of CCL2 mRNA and MMP-9 mRNA, but not IL-6 mRNA and iNOS mRNA expression. Furthermore, treatment with RGFP966, a selective histone deacetylase 3 (HDAC3) inhibitor, potently reversed the inhibitory effects of GSK4112 on TNF-induced expression of MMP-9 mRNA, but not CCL2 mRNA. Expression of Rev-erbs mRNA in C6 astroglial cells, primary cultured rat cortical and spinal astrocytes was confirmed by reverse transcription polymerase chain reaction. Together, the findings demonstrate an anti-inflammatory effect, downregulating of MMP-9 and CCL2 transcription, of astroglial REV-ERBs activation through HDAC3-dependent and HDAC3-independent mechanisms. - Highlights: • Rev-erbα mRNA and Rev-erbβ mRNA are expressed in C6 astroglial cells. • TNF increases the expression of CCL2, IL-6, MMP-9 and iNOS mRNA. • REV-ERB activation inhibits CCL2 mRNA and MMP-9 mRNA expression. • HDAC3 activity is involved in the inhibitory effect of REV-ERB on MMP-9

[Expression of cell adhesion molecules in acute leukemia cell].

PubMed

Ju, Xiaoping; Peng, Min; Xu, Xiaoping; Lu, Shuqing; Li, Yao; Ying, Kang; Xie, Yi; Mao, Yumin; Xia, Fang

2002-11-01

To investigate the role of cell adhesion molecule in the development and extramedullary infiltration (EI) of acute leukemia. The expressions of neural cell adhesion molecule (NCAM) gene, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule (VCAM-1) genes in 25 acute leukemia patients bone marrow cells were detected by microarray and reverse transcriptase-polymerase chain reaction (RT-PCR). The expressions of NCAM, ICAM-1 and VCAM-1 gene were significantly higher in acute leukemia cells and leukemia cells with EI than in normal tissues and leukemia cells without EI, respectively, both by cDNA microarray and by RT-PCR. The cDNA microarray is a powerful technique in analysis of acute leukemia cells associated genes. High expressions of cell adhesion molecule genes might be correlated with leukemia pathogenesis and infiltration of acute leukemia cell.

Withaferin A inhibits tumor necrosis factor-alpha-induced expression of cell adhesion molecules by inactivation of Akt and NF-kappaB in human pulmonary epithelial cells.

PubMed

Oh, Jung Hwa; Kwon, Taeg Kyu

2009-05-01

We here investigated the functional effect of withaferin A on airway inflammation and its action mechanism. Withaferin A inhibited the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in human lung epithelial A549 cells stimulated with tumor necrosis factor-alpha (TNF-alpha), resulting in the suppression of leukocyte adhesion to lung epithelial A549 cells. In addition, withaferin A inhibited TNF-alpha-induced expression of adhesion molecules (ICAM-1 and VCAM-1) protein and mRNA in a dose-dependent manner. Withaferin A prevented DNA binding activity of nuclear factor-kappaB (NF-kappaB) and nuclear translocation of NF-kappaB. It also inhibited phosphorylation of Akt and extracellular signal-regulated kinase (ERK), which are upstream in the regulation of adhesion molecules by TNF-alpha. Furthermore, withaferin A inhibited U937 monocyte adhesion to A549 cells stimulated by TNF-alpha, suggesting that it may inhibit the binding of these cells by regulating the expression of critical adhesion molecules by TNF-alpha. Taken together, these results suggest that withaferin A inhibits cell adhesion through inhibition of ICAM-1 and VCAM-1 expression, at least in part, by blocking Akt and down-regulating NF-kappaB activity.

Epigenetic Mechanisms Regulate MHC and Antigen Processing Molecules in Human Embryonic and Induced Pluripotent Stem Cells

PubMed Central

Suárez-Álvarez, Beatriz; Rodriguez, Ramón M.; Calvanese, Vincenzo; Blanco-Gelaz, Miguel A.; Suhr, Steve T.; Ortega, Francisco; Otero, Jesus; Cibelli, Jose B.; Moore, Harry; Fraga, Mario F.; López-Larrea, Carlos

2010-01-01

Background Human embryonic stem cells (hESCs) are an attractive resource for new therapeutic approaches that involve tissue regeneration. hESCs have exhibited low immunogenicity due to low levels of Mayor Histocompatibility Complex (MHC) class-I and absence of MHC class-II expression. Nevertheless, the mechanisms regulating MHC expression in hESCs had not been explored. Methodology/Principal Findings We analyzed the expression levels of classical and non-classical MHC class-I, MHC class-II molecules, antigen-processing machinery (APM) components and NKG2D ligands (NKG2D-L) in hESCs, induced pluripotent stem cells (iPSCs) and NTera2 (NT2) teratocarcinoma cell line. Epigenetic mechanisms involved in the regulation of these genes were investigated by bisulfite sequencing and chromatin immunoprecipitation (ChIP) assays. We showed that low levels of MHC class-I molecules were associated with absent or reduced expression of the transporter associated with antigen processing 1 (TAP-1) and tapasin (TPN) components in hESCs and iPSCs, which are involved in the transport and load of peptides. Furthermore, lack of β2-microglobulin (β2m) light chain in these cells limited the expression of MHC class I trimeric molecule on the cell surface. NKG2D ligands (MICA, MICB) were observed in all pluripotent stem cells lines. Epigenetic analysis showed that H3K9me3 repressed the TPN gene in undifferentiated cells whilst HLA-B and β2m acquired the H3K4me3 modification during the differentiation to embryoid bodies (EBs). Absence of HLA-DR and HLA-G expression was regulated by DNA methylation. Conclusions/Significance Our data provide fundamental evidence for the epigenetic control of MHC in hESCs and iPSCs. Reduced MHC class I and class II expression in hESCs and iPSCs can limit their recognition by the immune response against these cells. The knowledge of these mechanisms will further allow the development of strategies to induce tolerance and improve stem cell allograft acceptance

Vascular cell adhesion molecule-1 (VCAM-1) gene transcription and expression are regulated through an antioxidant-sensitive mechanism in human vascular endothelial cells.

PubMed Central

Marui, N; Offermann, M K; Swerlick, R; Kunsch, C; Rosen, C A; Ahmad, M; Alexander, R W; Medford, R M

1993-01-01

Oxidative stress and expression of the vascular cell adhesion molecule-1 (VCAM-1) on vascular endothelial cells are early features in the pathogenesis of atherosclerosis and other inflammatory diseases. Regulation of VCAM-1 gene expression may be coupled to oxidative stress through specific reduction-oxidation (redox) sensitive transcriptional or posttranscriptional regulatory factors. In cultured human umbilical vein endothelial (HUVE) cells, the cytokine interleukin 1 beta (IL-1 beta) activated VCAM-1 gene expression through a mechanism that was repressed approximately 90% by the antioxidants pyrrolidine dithiocarbamate (PDTC) and N-acetylcysteine (NAC). Furthermore, PDTC selectively inhibited the induction of VCAM-1, but not intercellular adhesion molecule-1 (ICAM-1), mRNA and protein accumulation by the cytokine tumor necrosis factor-alpha (TNF alpha) as well as the noncytokines bacterial endotoxin lipopolysaccharide (LPS) and double-stranded RNA, poly(I:C) (PIC). PDTC also markedly attenuated TNF alpha induction of VCAM-1-mediated cellular adhesion. In a distinct pattern, PDTC partially inhibited E-selectin gene expression in response to TNF alpha but not to LPS, IL-1 beta, or PIC. TNF alpha and LPS-mediated transcriptional activation of the human VCAM-1 promoter through NF-kappa B-like DNA enhancer elements and associated NF-kappa B-like DNA binding proteins was inhibited by PDTC. These studies suggest a molecular linkage between an antioxidant sensitive transcriptional regulatory mechanism and VCAM-1 gene expression that expands on the notion of oxidative stress as an important regulatory signal in the pathogenesis of atherosclerosis. Images PMID:7691889

The role of MicroRNA molecules and MicroRNA-regulating machinery in the pathogenesis and progression of epithelial ovarian cancer.

PubMed

Wang, Xiyin; Ivan, Mircea; Hawkins, Shannon M

2017-11-01

MicroRNA molecules are small, single-stranded RNA molecules that function to regulate networks of genes. They play important roles in normal female reproductive tract biology, as well as in the pathogenesis and progression of epithelial ovarian cancer. DROSHA, DICER, and Argonaute proteins are components of the microRNA-regulatory machinery and mediate microRNA production and function. This review discusses aberrant expression of microRNA molecules and microRNA-regulating machinery associated with clinical features of epithelial ovarian cancer. Understanding the regulation of microRNA molecule production and function may facilitate the development of novel diagnostic and therapeutic strategies to improve the prognosis of women with epithelial ovarian cancer. Additionally, understanding microRNA molecules and microRNA-regulatory machinery associations with clinical features may influence prevention and early detection efforts. Copyright © 2017 Elsevier Inc. All rights reserved.

Altered expression of CD1d molecules and lipid accumulation in the human hepatoma cell line HepG2 after iron loading.

PubMed

Cabrita, Marisa; Pereira, Carlos F; Rodrigues, Pedro; Cardoso, Elsa M; Arosa, Fernando A

2005-01-01

Iron overload in the liver may occur in clinical conditions such as hemochromatosis and nonalcoholic steatohepatitis, and may lead to the deterioration of the normal liver architecture by mechanisms not well understood. Although a relationship between the expression of ICAM-1, and classical major histocompatibility complex (MHC) class I molecules, and iron overload has been reported, no relationship has been identified between iron overload and the expression of unconventional MHC class I molecules. Herein, we report that parameters of iron metabolism were regulated in a coordinated-fashion in a human hepatoma cell line (HepG2 cells) after iron loading, leading to increased cellular oxidative stress and growth retardation. Iron loading of HepG2 cells resulted in increased expression of Nor3.2-reactive CD1d molecules at the plasma membrane. Expression of classical MHC class I and II molecules, ICAM-1 and the epithelial CD8 ligand, gp180 was not significantly affected by iron. Considering that intracellular lipids regulate expression of CD1d at the cell surface, we examined parameters of lipid metabolism in iron-loaded HepG2 cells. Interestingly, increased expression of CD1d molecules by iron-loaded HepG2 cells was associated with increased phosphatidylserine expression in the outer leaflet of the plasma membrane and the presence of many intracellular lipid droplets. These data describe a new relationship between iron loading, lipid accumulation and altered expression of CD1d, an unconventional MHC class I molecule reported to monitor intracellular and plasma membrane lipid metabolism, in the human hepatoma cell line HepG2.

Differential Expression of Osteo-Modulatory Molecules in Periodontal Ligament Stem Cells in Response to Modified Titanium Surfaces

PubMed Central

Kim, So Yeon; Yoo, Ji-Yeon; Ohe, Joo-Young; Lee, Jung-Woo; Moon, Ji-Hoi; Kwon, Yong-Dae; Heo, Jung Sun

2014-01-01

This study assessed differential gene expression of signaling molecules involved in osteogenic differentiation of periodontal ligament stem cells (PDLSCs) subjected to different titanium (Ti) surface types. PDLSCs were cultured on tissue culture polystyrene (TCPS), and four types of Ti discs (PT, SLA, hydrophilic PT (pmodPT), and hydrophilic SLA (modSLA)) with no osteoinductive factor and then osteogenic activity, including alkaline phosphatase (ALP) activity, mRNA expression of runt-related gene 2, osterix, FOSB, FRA1, and protein levels of osteopontin and collagen type IA, were examined. The highest osteogenic activity appeared in PDLSCs cultured on SLA, compared with the TCPS and other Ti surfaces. The role of surface properties in affecting signaling molecules to modulate PDLSC behavior was determined by examining the regulation of Wnt pathways. mRNA expression of the canonical Wnt signaling molecules, Wnt3a and β-catenin, was higher on SLA and modSLA than on smooth surfaces, but gene expression of the calcium-dependent Wnt signaling molecules Wnt5a, calmodulin, and NFATc1 was increased significantly on PT and pmodPT. Moreover, integrin α2/β1, sonic hedgehog, and Notch signaling molecules were affected differently by each surface modification. In conclusion, surface roughness and hydrophilicity can affect differential Wnt pathways and signaling molecules, targeting the osteogenic differentiation of PDLSCs. PMID:25057487

Differential expression of osteo-modulatory molecules in periodontal ligament stem cells in response to modified titanium surfaces.

PubMed

Kim, So Yeon; Yoo, Ji-Yeon; Ohe, Joo-Young; Lee, Jung-Woo; Moon, Ji-Hoi; Kwon, Yong-Dae; Heo, Jung Sun

2014-01-01

This study assessed differential gene expression of signaling molecules involved in osteogenic differentiation of periodontal ligament stem cells (PDLSCs) subjected to different titanium (Ti) surface types. PDLSCs were cultured on tissue culture polystyrene (TCPS), and four types of Ti discs (PT, SLA, hydrophilic PT (pmodPT), and hydrophilic SLA (modSLA)) with no osteoinductive factor and then osteogenic activity, including alkaline phosphatase (ALP) activity, mRNA expression of runt-related gene 2, osterix, FOSB, FRA1, and protein levels of osteopontin and collagen type IA, were examined. The highest osteogenic activity appeared in PDLSCs cultured on SLA, compared with the TCPS and other Ti surfaces. The role of surface properties in affecting signaling molecules to modulate PDLSC behavior was determined by examining the regulation of Wnt pathways. mRNA expression of the canonical Wnt signaling molecules, Wnt3a and β-catenin, was higher on SLA and modSLA than on smooth surfaces, but gene expression of the calcium-dependent Wnt signaling molecules Wnt5a, calmodulin, and NFATc1 was increased significantly on PT and pmodPT. Moreover, integrin α2/β1, sonic hedgehog, and Notch signaling molecules were affected differently by each surface modification. In conclusion, surface roughness and hydrophilicity can affect differential Wnt pathways and signaling molecules, targeting the osteogenic differentiation of PDLSCs.

Expression of Inflammation-related Intercellular Adhesion Molecules in Cardiomyocytes In Vitro and Modulation by Pro-inflammatory Agents.

PubMed

El-Battrawy, Ibrahim; Tülümen, Erol; Lang, Siegfried; Akin, Ibrahim; Behnes, Michael; Zhou, Xiabo; Mavany, Martin; Bugert, Peter; Bieback, Karen; Borggrefe, Martin; Elmas, Elif

2016-01-01

Cell-surface adhesion molecules regulate multiple intercellular and intracellular processes and play important roles in inflammation by facilitating leukocyte endothelial transmigration. Whether cardiomyocytes express surface-adhesion molecules related to inflammation and the effect of pro-inflammatory mediators remain unknown. In the present study, the expression of different cell-adhesion molecules (CD11a, CD11b, CD31, CD62P, CD162, F11 receptor and mucosal vascular addressin cell adhesion molecule 1 (MADCAM1)) and the effect of pro-inflammatory mediators were investigated in an in vitro model of human cardiomyocytes. Cells were supplied as a primary culture of cardiac alpha actin-positive cells from human heart tissue. The cells were incubated for 24 h with 1 U/ml thrombin or 700 ng/ml lipopolysaccharide (LPS) or with a combination of both. The expression of the cell adhesion molecules was measured by flow cytometry. In cultured human cardiomyocytes, 22.8% of cells expressed CD31, 7.1% MADCAM1 and 2.6% F11R. CD11a, CD11b, CD62P and CD162 were expressed by fewer than 2% of the cells at baseline. CD31 expression increased on incubation of cardiomyocytes with thrombin by 26% (p<0.05) and with LPS by 26% (p=0.06). The combination of thrombin and LPS did not result in increased levels of CD31 (p>0.10). The pro-inflammatory agents LPS and thrombin had no effect on the expression of MADCAM1 and F11R. Inflammation-related cell-adhesion molecules CD31, MADCAM1 and F11R were shown to be expressed on the surface of human cardiomyocytes in an in vitro model. Incubation with LPS or thrombin resulted in increased expression of CD31, however, it did not modify the expression of the cell adhesion molecules MADCAM1 and F11R. Copyright © 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Adaptive Control Model Reveals Systematic Feedback and Key Molecules in Metabolic Pathway Regulation

PubMed Central

Moffitt, Richard A.; Merrill, Alfred H.; Wang, May D.

2011-01-01

Abstract Robust behavior in metabolic pathways resembles stabilized performance in systems under autonomous control. This suggests we can apply control theory to study existing regulation in these cellular networks. Here, we use model-reference adaptive control (MRAC) to investigate the dynamics of de novo sphingolipid synthesis regulation in a combined theoretical and experimental case study. The effects of serine palmitoyltransferase over-expression on this pathway are studied in vitro using human embryonic kidney cells. We report two key results from comparing numerical simulations with observed data. First, MRAC simulations of pathway dynamics are comparable to simulations from a standard model using mass action kinetics. The root-sum-square (RSS) between data and simulations in both cases differ by less than 5%. Second, MRAC simulations suggest systematic pathway regulation in terms of adaptive feedback from individual molecules. In response to increased metabolite levels available for de novo sphingolipid synthesis, feedback from molecules along the main artery of the pathway is regulated more frequently and with greater amplitude than from other molecules along the branches. These biological insights are consistent with current knowledge while being new that they may guide future research in sphingolipid biology. In summary, we report a novel approach to study regulation in cellular networks by applying control theory in the context of robust metabolic pathways. We do this to uncover potential insight into the dynamics of regulation and the reverse engineering of cellular networks for systems biology. This new modeling approach and the implementation routines designed for this case study may be extended to other systems. Supplementary Material is available at www.liebertonline.com/cmb. PMID:21314456

Major histocompatibility complex class II molecule expression on muscle cells is regulated by differentiation: implications for the immunopathogenesis of muscle autoimmune diseases.

PubMed

Mantegazza, R; Gebbia, M; Mora, M; Barresi, R; Bernasconi, P; Baggi, F; Cornelio, F

1996-08-01

Major histocompatibility complex (MHC) class II molecules are expressed on myoblasts after interferon-gamma (IFN-gamma) treatment, suggesting a muscle cell involvement in antigen presentation in inflammatory myopathies. However, they were not observed on normal or pathological myofibers. This discrepancy might be related to different responsiveness of developmentally differentiated muscle cells to IFN-gamma. Myoblasts expressed class II transcripts and proteins after IFN-gamma, while myotubes and innervated contracting muscle cells did not show staining for class II molecules. At all cell stages no loss of IFN-gamma receptor was detected indicating that myofiber maturation blocks their capacity to express MHC class II molecules. This suggests that completely differentiated myofibers cannot participate in class II restricted immunological reactions.

Vitamins K2, K3 and K5 exert in vivo antitumor effects on hepatocellular carcinoma by regulating the expression of G1 phase-related cell cycle molecules.

PubMed

Kuriyama, Shigeki; Hitomi, Misuzu; Yoshiji, Hitoshi; Nonomura, Takako; Tsujimoto, Tatsuhiro; Mitoro, Akira; Akahane, Takami; Ogawa, Mutsumi; Nakai, Seiji; Deguchi, Akihiro; Masaki, Tsutomu; Uchida, Naohito

2005-08-01

A number of studies have shown that various vitamins K, specifically vitamin K2, possessed antitumor activity on various types of rodent- and human-derived neoplastic cell lines. However, there are only a small number of reports demonstrating in vivo antitumor effects of vitamins K. Furthermore, the mechanism of antitumor effects of vitamins K still remains to be examined. In the present study, we examined the antitumor effects of vitamins K2, K3 and K5 on PLC/PRF/5 human hepatocellular carcinoma (HCC) cells in vivo. Furthermore, to examine the mechanism of antitumor actions of these vitamins K, mRNA expression levels of various G1 phase-related cell cycle molecules were evaluated by using a real-time reverse transcription-polymerase chain reaction (RT-PCR) method. HCC-bearing animals were produced by implanting PLC/PRF/5 cells subcutaneously into athymic nude mice, and drinking water containing vitamin K2, K3 or K5 was given to the animals. Treatments with vitamins K2, K3 and K5 were shown to markedly inhibit the growth of HCC tumors. To examine the mechanism of in vivo antitumor effects of vitamins K, total RNA was extracted from HCC tumors, and the expression of G1 phase-related cell cycle molecules was quantitatively examined. Real-time RT-PCR demonstrated that the expression of the cell cycle-driving molecule, cyclin-dependent kinase 4 (Cdk4), in HCC was significantly reduced by the treatments with vitamin K2, K3 and K5. Conversely, the expression of the cell cycle-suppressing molecules, Cdk inhibitor p16INK4a and retinoblastoma, in HCC was significantly enhanced by the treatments with vitamins K2, K3 and K5. These results indicate that vitamins K2, K3 and K5 exert antitumor effects on HCC by regulating the expression of G1 phase-related cell cycle molecules. These results also indicate that vitamins K2, K3 and K5 may be useful agents for the treatment of patients with HCC.

Reversible epigenetic down-regulation of MHC molecules by devil facial tumour disease illustrates immune escape by a contagious cancer

PubMed Central

Siddle, Hannah V.; Kreiss, Alexandre; Tovar, Cesar; Yuen, Chun Kit; Cheng, Yuanyuan; Belov, Katherine; Swift, Kate; Pearse, Anne-Maree; Hamede, Rodrigo; Jones, Menna E.; Skjødt, Karsten; Woods, Gregory M.; Kaufman, Jim

2013-01-01

Contagious cancers that pass between individuals as an infectious cell line are highly unusual pathogens. Devil facial tumor disease (DFTD) is one such contagious cancer that emerged 16 y ago and is driving the Tasmanian devil to extinction. As both a pathogen and an allograft, DFTD cells should be rejected by the host–immune response, yet DFTD causes 100% mortality among infected devils with no apparent rejection of tumor cells. Why DFTD cells are not rejected has been a question of considerable confusion. Here, we show that DFTD cells do not express cell surface MHC molecules in vitro or in vivo, due to down-regulation of genes essential to the antigen-processing pathway, such as β2-microglobulin and transporters associated with antigen processing. Loss of gene expression is not due to structural mutations, but to regulatory changes including epigenetic deacetylation of histones. Consequently, MHC class I molecules can be restored to the surface of DFTD cells in vitro by using recombinant devil IFN-γ, which is associated with up-regulation of the MHC class II transactivator, a key transcription factor with deacetylase activity. Further, expression of MHC class I molecules by DFTD cells can occur in vivo during lymphocyte infiltration. These results explain why T cells do not target DFTD cells. We propose that MHC-positive or epigenetically modified DFTD cells may provide a vaccine to DFTD. In addition, we suggest that down-regulation of MHC molecules using regulatory mechanisms allows evolvability of transmissible cancers and could affect the evolutionary trajectory of DFTD. PMID:23479617

Ezrin Inhibition Up-regulates Stress Response Gene Expression*

PubMed Central

Çelik, Haydar; Bulut, Gülay; Han, Jenny; Graham, Garrett T.; Minas, Tsion Z.; Conn, Erin J.; Hong, Sung-Hyeok; Pauly, Gary T.; Hayran, Mutlu; Li, Xin; Özdemirli, Metin; Ayhan, Ayşe; Rudek, Michelle A.; Toretsky, Jeffrey A.; Üren, Aykut

2016-01-01

Ezrin is a member of the ERM (ezrin/radixin/moesin) family of proteins that links cortical cytoskeleton to the plasma membrane. High expression of ezrin correlates with poor prognosis and metastasis in osteosarcoma. In this study, to uncover specific cellular responses evoked by ezrin inhibition that can be used as a specific pharmacodynamic marker(s), we profiled global gene expression in osteosarcoma cells after treatment with small molecule ezrin inhibitors, NSC305787 and NSC668394. We identified and validated several up-regulated integrated stress response genes including PTGS2, ATF3, DDIT3, DDIT4, TRIB3, and ATF4 as novel ezrin-regulated transcripts. Analysis of transcriptional response in skin and peripheral blood mononuclear cells from NSC305787-treated mice compared with a control group revealed that, among those genes, the stress gene DDIT4/REDD1 may be used as a surrogate pharmacodynamic marker of ezrin inhibitor compound activity. In addition, we validated the anti-metastatic effects of NSC305787 in reducing the incidence of lung metastasis in a genetically engineered mouse model of osteosarcoma and evaluated the pharmacokinetics of NSC305787 and NSC668394 in mice. In conclusion, our findings suggest that cytoplasmic ezrin, previously considered a dormant and inactive protein, has important functions in regulating gene expression that may result in down-regulation of stress response genes. PMID:27137931

Circular RNA Expression: Its Potential Regulation and Function.

PubMed

Salzman, Julia

2016-05-01

In 2012, a new feature of eukaryotic gene expression emerged: ubiquitous expression of circular RNA (circRNA) from genes traditionally thought to express messenger or linear noncoding (nc)RNA only. CircRNAs are covalently closed, circular RNA molecules that typically comprise exonic sequences and are spliced at canonical splice sites. This feature of gene expression was first recognized in humans and mouse, but it quickly emerged that it was common across essentially all eukaryotes studied by molecular biologists. CircRNA abundance, and even which alternatively spliced circRNA isoforms are expressed, varies by cell type and can exceed the abundance of the traditional linear mRNA or ncRNA transcript. CircRNAs are enriched in the brain and increase in abundance during fetal development. Together, these features raise fundamental questions regarding the regulation of circRNA in cis and in trans, and its function. Copyright © 2016. Published by Elsevier Ltd.

Artificial dental pulp exposure injury up-regulates antigen-presenting cell-related molecules in rat central nervous system.

PubMed

Kaneko, Tomoatsu; Kaneko, Mitsuhiro; Chokechanachaisakul, Uraiwan; Kawamura, Jun; Kaneko, Reika; Sunakawa, Mitsuhiro; Okiji, Takashi; Suda, Hideaki

2010-03-01

Bacterial infection and resulting inflammation of the dental pulp might not only trigger neuroimmune interactions in this tissue but also sensitize the central nervous system (CNS) such as the thalamus via nociceptive neurons. Thus, immunopathologic changes in the rat thalamus that take place after pulp inflammation were investigated. Pulp exposure was made in mandibular right first molars of 5-week-old Wistar rats. After 24 hours, the thalamus was retrieved and subjected to either immunohistochemistry for class II major histocompatibility complex (MHC) molecules and glial fibrillary acidic protein (GFAP) or mRNA expression analysis of antigen-presenting cell-related molecules and N-methyl-D-aspartate receptor 2D subunit (NR2D) by means of reverse transcription-polymerase chain reaction (RT-PCR) and real-time PCR. At 24 hours after pulp exposure, the density of class II MHC molecule-expressing and GFAP-expressing cells was increased in the contralateral thalamus. Gene expression analysis revealed the up-regulation of class II MHC molecules, CD80, CD83, CD86, and NR2D in the contralateral thalamus, as compared with the ipsilateral thalamus. These results suggest the signal of pulp inflammation induces neuronal activation in the CNS. Copyright (c) 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

CD1 molecule expression on human monocytes induced by granulocyte-macrophage colony-stimulating factor.

PubMed

Kasinrerk, W; Baumruker, T; Majdic, O; Knapp, W; Stockinger, H

1993-01-15

In this paper we demonstrate that granulocyte-macrophage CSF (GM-CSF) specifically induces the expression of CD1 molecules, CD1a, CD1b and CD1c, upon human monocytes. CD1 molecules appeared upon monocytes on day 1 of stimulation with rGM-CSF, and expression was up-regulated until day 3. Monocytes cultured in the presence of LPS, FMLP, PMA, recombinant granulocyte-CSF, rIFN-gamma, rTNF-alpha, rIL-1 alpha, rIL-1 beta, and rIL-6 remained negative. The induction of CD1 molecules by rGM-CSF was restricted to monocytes, since no such effect was observed upon peripheral blood granulocytes, PBL, and the myeloid cell lines Monomac1, Monomac6, MV4/11, HL60, U937, THP1, KG1, and KG1A. CD1a mRNA was detectable in rGM-CSF-induced monocytes but not in those freshly isolated. SDS-PAGE and immunoblotting analyses of CD1a mAb VIT6 immunoprecipitate from lysate of rGM-CSF-activated monocytes revealed an appropriate CD1a polypeptide band of 49 kDa associated with beta 2-microglobulin. Expression of CD1 molecules on monocytes complements the distribution of these structures on accessory cells, and their specific induction by GM-CSF strengthens the suggestion that CD1 is a family of crucial structures required for interaction between accessory cells and T cells.

ZDHHC3 Tyrosine Phosphorylation Regulates Neural Cell Adhesion Molecule Palmitoylation

PubMed Central

Lievens, Patricia Marie-Jeanne; Kuznetsova, Tatiana; Kochlamazashvili, Gaga; Cesca, Fabrizia; Gorinski, Natalya; Galil, Dalia Abdel; Cherkas, Volodimir; Ronkina, Natalia; Lafera, Juri; Gaestel, Matthias

2016-01-01

The neural cell adhesion molecule (NCAM) mediates cell-cell and cell-matrix adhesion. It is broadly expressed in the nervous system and regulates neurite outgrowth, synaptogenesis, and synaptic plasticity. Previous in vitro studies revealed that palmitoylation of NCAM is required for fibroblast growth factor 2 (FGF2)-stimulated neurite outgrowth and identified the zinc finger DHHC (Asp-His-His-Cys)-containing proteins ZDHHC3 and ZDHHC7 as specific NCAM-palmitoylating enzymes. Here, we verified that FGF2 controlled NCAM palmitoylation in vivo and investigated molecular mechanisms regulating NCAM palmitoylation by ZDHHC3. Experiments with overexpression and pharmacological inhibition of FGF receptor (FGFR) and Src revealed that these kinases control tyrosine phosphorylation of ZDHHC3 and that ZDHHC3 is phosphorylated by endogenously expressed FGFR and Src proteins. By site-directed mutagenesis, we found that Tyr18 is an FGFR1-specific ZDHHC3 phosphorylation site, while Tyr295 and Tyr297 are specifically phosphorylated by Src kinase in cell-based and cell-free assays. Abrogation of tyrosine phosphorylation increased ZDHHC3 autopalmitoylation, enhanced interaction with NCAM, and upregulated NCAM palmitoylation. Expression of ZDHHC3 with tyrosine mutated in cultured hippocampal neurons promoted neurite outgrowth. Our findings for the first time highlight that FGFR- and Src-mediated tyrosine phosphorylation of ZDHHC3 modulates ZDHHC3 enzymatic activity and plays a role in neuronal morphogenesis. PMID:27247265

Zebrafish E-cadherin: expression during early embryogenesis and regulation during brain development.

PubMed

Babb, S G; Barnett, J; Doedens, A L; Cobb, N; Liu, Q; Sorkin, B C; Yelick, P C; Raymond, P A; Marrs, J A

2001-06-01

Zebrafish E-cadherin (cdh1) cell adhesion molecule cDNAs were cloned. We investigated spatial and temporal expression of cdh1 during early embryogenesis. Expression was observed in blastomeres, the anterior mesoderm during gastrulation, and developing epithelial structures. In the developing nervous system, cdh1 was detected at the pharyngula stage (24 hpf) in the midbrain-hindbrain boundary (MHB). Developmental regulation of MHB formation involves wnt1 and pax2.1. wnt1 expression preceded cdh1 expression during MHB formation, and cdh1 expression in the MHB was dependent on normal development of this structure. Copyright 2001 Wiley-Liss, Inc.

IL-10 down-regulates T cell activation by antigen-presenting liver sinusoidal endothelial cells through decreased antigen uptake via the mannose receptor and lowered surface expression of accessory molecules.

PubMed

Knolle, P A; Uhrig, A; Hegenbarth, S; Löser, E; Schmitt, E; Gerken, G; Lohse, A W

1998-12-01

Our study demonstrates that antigen-presenting liver sinusoidal endothelial cells (LSEC) induce production of interferon-gamma (IFN-gamma) from cloned Th1 CD4+ T cells. We show that LSEC used the mannose receptor for antigen uptake, which further strengthened the role of LSEC as antigen-presenting cell (APC) population in the liver. The ability of LSEC to activate cloned CD4+ T cells antigen-specifically was down-regulated by exogenous prostaglandin E2 (PGE2) and by IL-10. We identify two separate mechanisms by which IL-10 down-regulated T cell activation through LSEC. IL-10 decreased the constitutive surface expression of MHC class II as well as of the accessory molecules CD80 and CD86 on LSEC. Furthermore, IL-10 diminished mannose receptor activity in LSEC. Decreased antigen uptake via the mannose receptor and decreased expression of accessory molecules may explain the down-regulation of T cell activation through IL-10. Importantly, the expression of low numbers of antigen on MHC II in the absence of accessory signals on LSEC may lead to induction of anergy in T cells. Because PGE2 and IL-10 are released from LSEC or Kupffer cells (KC) in response to those concentrations of endotoxin found physiologically in portal venous blood, it is possible that the continuous presence of these mediators and their negative effect on the local APC may explain the inability of the liver to induce T cell activation and to clear chronic infections. Our results support the notion that antigen presentation by LSEC in the hepatic microenvironment contributes to the observed inability to mount an effective cell-mediated immune response in the liver.

Expression of cell adhesion molecules in the normal and T3 blocked development of the tadpole's kidney of Bufo arenarum (Amphibian, Anuran, Bufonidae).

PubMed

Izaguirre, M F; García-Sancho, M N; Miranda, L A; Tomas, J; Casco, V H

2008-08-01

Cell adhesion molecules act as signal transducers from the extracellular environment to the cytoskeleton and the nucleus and consequently induce changes in the expression pattern of structural proteins. In this study, we showed the effect of thyroid hormone (TH) inhibition and arrest of metamorphosis on the expression of E-cadherin, beta-and alpha-catenin in the developing kidney of Bufo arenarum. Cell adhesion molecules have selective temporal and spatial expression during development suggesting a specific role in nephrogenesis. In order to study mechanisms controlling the expression of adhesion molecules during renal development, we blocked the B. arenarum metamorphosis with a goitrogenic substance that blocks TH synthesis. E-cadherin expression in the proximal tubules is independent of thyroid control. However, the blockage of TH synthesis causes up-regulation of E-cadherin in the collecting ducts, the distal tubules and the glomeruli. The expression of beta-and alpha-catenin in the collecting ducts, the distal tubules, the glomeruli and the mesonephric mesenchyme is independent of TH. TH blockage causes up-regulation of beta-and alpha-catenin in the proximal tubules. In contrast to E-cadherin, the expression of the desmosomal cadherin desmoglein 1 (Dsg-1) is absent in the control of the larvae kidney during metamorphosis and is expressed in some interstitial cells in the KClO4 treated larvae. According to this work, the Dsg-1 expression is down-regulated by TH. We demonstrated that the expression of E-cadherin, Dsg-1, beta-catenin and alpha-catenin are differentially affected by TH levels, suggesting a hormone-dependent role of these proteins in the B. arenarum renal metamorphosis.

Ezrin Inhibition Up-regulates Stress Response Gene Expression.

PubMed

Çelik, Haydar; Bulut, Gülay; Han, Jenny; Graham, Garrett T; Minas, Tsion Z; Conn, Erin J; Hong, Sung-Hyeok; Pauly, Gary T; Hayran, Mutlu; Li, Xin; Özdemirli, Metin; Ayhan, Ayşe; Rudek, Michelle A; Toretsky, Jeffrey A; Üren, Aykut

2016-06-17

Ezrin is a member of the ERM (ezrin/radixin/moesin) family of proteins that links cortical cytoskeleton to the plasma membrane. High expression of ezrin correlates with poor prognosis and metastasis in osteosarcoma. In this study, to uncover specific cellular responses evoked by ezrin inhibition that can be used as a specific pharmacodynamic marker(s), we profiled global gene expression in osteosarcoma cells after treatment with small molecule ezrin inhibitors, NSC305787 and NSC668394. We identified and validated several up-regulated integrated stress response genes including PTGS2, ATF3, DDIT3, DDIT4, TRIB3, and ATF4 as novel ezrin-regulated transcripts. Analysis of transcriptional response in skin and peripheral blood mononuclear cells from NSC305787-treated mice compared with a control group revealed that, among those genes, the stress gene DDIT4/REDD1 may be used as a surrogate pharmacodynamic marker of ezrin inhibitor compound activity. In addition, we validated the anti-metastatic effects of NSC305787 in reducing the incidence of lung metastasis in a genetically engineered mouse model of osteosarcoma and evaluated the pharmacokinetics of NSC305787 and NSC668394 in mice. In conclusion, our findings suggest that cytoplasmic ezrin, previously considered a dormant and inactive protein, has important functions in regulating gene expression that may result in down-regulation of stress response genes. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Prognostic implications of adhesion molecule expression in colorectal cancer.

PubMed

Seo, Kyung-Jin; Kim, Maru; Kim, Jeana

2015-01-01

Research on the expression of adhesion molecules, E-cadherin (ECAD), CD24, CD44 and osteopontin (OPN) in colorectal cancer (CRC) has been limited, even though CRC is one of the leading causes of cancer-related deaths. This study was conducted to evaluate the expression of adhesion molecules in CRC and to determine their relationships with clinicopathologic variables, and the prognostic significance. The expression of ECAD, CD24, CD44 and OPN was examined in 174 stage II and III CRC specimens by immunohistochemistry of TMA. Negative ECAD expression was significantly correlated with advanced nodal stage and poor tumor differentiation. Multivariate analysis showed that both negative expression of ECAD and positive expression of CD24 were independent prognostic factors for disease-free survival (DFS) in CRC patients (P<0.001, relative risk [RR] = 5.596, 95% CI = 2.712-11.549; P = 0.038, RR = 3.768, 95% CI = 1.077-13.185, respectively). However, for overall survival (OS), only ECAD negativity showed statistically significant results in multivariate analysis (P<0.001, RR = 4.819, 95% CI = 2.515-9.234). Positive expression of CD24 was associated with poor OS in univariate analysis but was of no prognostic value in multivariate analysis. In conclusion, our study suggests that among these four adhesion molecules, ECAD and CD24 expression can be considered independent prognostic factors. The role of CD44 and OPN may need further evaluation.

Prognostic implications of adhesion molecule expression in colorectal cancer

PubMed Central

Seo, Kyung-Jin; Kim, Maru; Kim, Jeana

2015-01-01

Research on the expression of adhesion molecules, E-cadherin (ECAD), CD24, CD44 and osteopontin (OPN) in colorectal cancer (CRC) has been limited, even though CRC is one of the leading causes of cancer-related deaths. This study was conducted to evaluate the expression of adhesion molecules in CRC and to determine their relationships with clinicopathologic variables, and the prognostic significance. The expression of ECAD, CD24, CD44 and OPN was examined in 174 stage II and III CRC specimens by immunohistochemistry of TMA. Negative ECAD expression was significantly correlated with advanced nodal stage and poor tumor differentiation. Multivariate analysis showed that both negative expression of ECAD and positive expression of CD24 were independent prognostic factors for disease-free survival (DFS) in CRC patients (P<0.001, relative risk [RR] = 5.596, 95% CI = 2.712-11.549; P = 0.038, RR = 3.768, 95% CI = 1.077-13.185, respectively). However, for overall survival (OS), only ECAD negativity showed statistically significant results in multivariate analysis (P<0.001, RR = 4.819, 95% CI = 2.515-9.234). Positive expression of CD24 was associated with poor OS in univariate analysis but was of no prognostic value in multivariate analysis. In conclusion, our study suggests that among these four adhesion molecules, ECAD and CD24 expression can be considered independent prognostic factors. The role of CD44 and OPN may need further evaluation. PMID:26097606

Amphiregulin enhances intercellular adhesion molecule-1 expression and promotes tumor metastasis in human osteosarcoma

PubMed Central

Liu, Ju-Fang; Tsao, Ya-Ting; Hou, Chun-Han

2015-01-01

Osteosarcoma is a common, high malignant, and metastatic bone cancer. Amphiregulin (AREG) has been associated with cancer cellular activities. However, the effect of AREG on metastasis activity in human osteosarcoma cells has yet to be determined. We determined that AREG increases the expression of intercellular adhesion molecule-1 (ICAM-1) through PI3K/Akt signaling pathway via its interaction with the epidermal growth factor receptor, thus resulting in the enhanced cell migration of osteosarcoma. Furthermore, AREG stimulation increased the association of NF-κB to ICAM-1 promoter which then up-regulated ICAM-1 expression. Finally, we observed that shRNA silencing of AREG decreased osteosarcoma metastasis in vivo. Our findings revealed a relationship between osteosarcoma metastatic potential and AREG expression and the modulating effect of AREG on ICAM-1 expression. PMID:26503469

Single-molecule quantification of lipotoxic expression of activating transcription factor 3

PubMed Central

Wilson, Dennis W.; Rutledge, John C.

2014-01-01

Activating transcription factor 3 (ATF3) is a member of the mammalian activation transcription factor/cAMP, physiologically important in the regulation of pro- and anti-inflammatory target genes. We compared the induction of ATF3 protein as measured by Western blot analysis with single-molecule localization microscopy dSTORM to quantify the dynamics of accumulation of intranuclear ATF3 of triglyceride-rich (TGRL) lipolysis product-treated HAEC (Human Aortic Endothelial Cells). The ATF3 expression rate within the first three hours after treatment with TGRL lipolysis products is about 3500/h. After three hours we detected 33,090 ± 3,491 single-molecule localizations of ATF3. This was accompanied by significant structural changes in the F-actin network of the cells at ~3-fold increased localization precision compared to widefield microscopy after treatment. Additionally, we discovered a cluster size of approximately 384 nanometers of ATF3 molecules. We show for the first time the time course of ATF3 accumulation in the nucleus undergoing lipotoxic injury. Furthermore, we demonstrate ATF3 accumulation associated with increased concentrations of TGRL lipolysis products occurs in large aggregates. PMID:25189785

Tissue distribution, regulation and intracellular localization of murine CD1 molecules.

PubMed

Mandal, M; Chen, X R; Alegre, M L; Chiu, N M; Chen, Y H; Castaño, A R; Wang, C R

1998-06-01

CD1 molecules are MHC-unlinked class Ib molecules consisting of classical (human CD 1a-c) and non-classical subsets (human CD1d and murine CD1). The characterization of non-classical subsets of CD1 is limited due to the lack of reagents. In this study, we have generated two new anti-mouse CD1 monoclonal antibodies, 3H3 and 5C6, by immunization of hamsters with purified CD1 protein. These antibodies recognize CD1-transfected cells and have no reactivity to cells isolated from CD1-/- mice. Both antibodies precipitate the 52 kDa heavy chain and 12 kDa beta2m from thymocytes and splenocytes by radio-immunoprecipitation. Deglycosylation of CD1 reduces molecular mass of the heavy chain by 7.5 kDa, which can be detected by 3H3 but not 5C6. 3H3 and 5C6 detect surface CD1 expression on cells from the thymus, spleen, lymph node and bone marrow, but not on intestinal epithelial cells. Developmentally, CD1 is expressed on thymocytes prior to TCR rearrangement and remains constant throughout thymic development. CD1 is expressed early in the fetal liver (day 14) and remains expressed in hepatocytes postnatally. These data support evidence of a role for CD1 in the selection and/or expansion of NK1- T cells of both thymic origin and extrathymic origin. Unlike classical class I molecules, murine CD1 levels are not affected by IFN-gamma, but like human CD1b can be up-regulated by IL-4 and GM-CSF although only moderately. Similar to human CD1b, murine CD1 is found by immunofluorescence microscopy on the cell surface, and in various intracellular vesicles, including early and late endosomes. Localization in endocytic compartments indicates that murine CD1 may be capable of binding endocytosed antigens.

Neuroprotective effect of treadmill exercise possibly via regulation of lysosomal degradation molecules in mice with pharmacologically induced Parkinson's disease.

PubMed

Hwang, Dong-Joo; Koo, Jung-Hoon; Kwon, Ki-Cheon; Choi, Dong-Hoon; Shin, Sung-Deuk; Jeong, Jae-Hoon; Um, Hyun-Seob; Cho, Joon-Yong

2017-12-19

Dysfunction of mitophagy, which is a selective degradation of defective mitochondria for quality control, is known to be implicated in the pathogenesis of Parkinson's disease (PD). However, how treadmill exercise (TE) regulates mitophagy-related molecules in PD remains to be elucidated. Therefore, we aimed to investigate how TE regulates α-synuclein (α-syn)-induced neurotoxicity and mitophagy-related molecules in the nigro-striatal region of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-mice. Our data showed that TE exhibited a significant restoration of tyrosine hydroxylase and motor coordination with suppression of α-syn expression, hallmarks of PD, possibly via up-regulation of lysosomal degradation molecules, LAMP-2 and cathepsin L, with down-regulation of p62, LC3-II/LC3-I ratio, PINK1 and parkin in the substantia nigra of MPTP mice. Therefore, these results suggest that treadmill exercise can be used as a non-invasive intervention to improve the pathological features and maintain a healthier mitochondrial network through appropriate elimination of defective mitochondria in PD.

The Temporal Dynamics of Arc Expression Regulate Cognitive Flexibility.

PubMed

Wall, Mark J; Collins, Dawn R; Chery, Samantha L; Allen, Zachary D; Pastuzyn, Elissa D; George, Arlene J; Nikolova, Viktoriya D; Moy, Sheryl S; Philpot, Benjamin D; Shepherd, Jason D; Müller, Jürgen; Ehlers, Michael D; Mabb, Angela M; Corrêa, Sonia A L

2018-06-27

Neuronal activity regulates the transcription and translation of the immediate-early gene Arc/Arg3.1, a key mediator of synaptic plasticity. Proteasome-dependent degradation of Arc tightly limits its temporal expression, yet the significance of this regulation remains unknown. We disrupted the temporal control of Arc degradation by creating an Arc knockin mouse (ArcKR) where the predominant Arc ubiquitination sites were mutated. ArcKR mice had intact spatial learning but showed specific deficits in selecting an optimal strategy during reversal learning. This cognitive inflexibility was coupled to changes in Arc mRNA and protein expression resulting in a reduced threshold to induce mGluR-LTD and enhanced mGluR-LTD amplitude. These findings show that the abnormal persistence of Arc protein limits the dynamic range of Arc signaling pathways specifically during reversal learning. Our work illuminates how the precise temporal control of activity-dependent molecules, such as Arc, regulates synaptic plasticity and is crucial for cognition. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Curcumin inhibits cancer progression through regulating expression of microRNAs.

PubMed

Zhou, Siying; Zhang, Sijie; Shen, Hongyu; Chen, Wei; Xu, Hanzi; Chen, Xiu; Sun, Dawei; Zhong, Shanliang; Zhao, Jianhua; Tang, Jinhai

2017-02-01

Curcumin, a major yellow pigment and spice in turmeric and curry, is a powerful anti-cancer agent. The anti-tumor activities of curcumin include inhibition of tumor proliferation, angiogenesis, invasion and metastasis, induction of tumor apoptosis, increase of chemotherapy sensitivity, and regulation of cell cycle and cancer stem cell, indicating that curcumin maybe a strong therapeutic potential through modulating various cancer progression. It has been reported that microRNAs as small noncoding RNA molecules are related to cancer progression, which can be regulated by curcumin. Dysregulated microRNAs play vital roles in tumor biology via regulating expressions of target genes and then influencing multiple cancer-related signaling pathways. In this review, we focused on the inhibition effect of curcumin on various cancer progression by regulating expression of multiple microRNAs. Curcumin-induced dysregulation of microRNAs may activate or inactivate a set of signaling pathways, such as Akt, Bcl-2, PTEN, p53, Notch, and Erbb signaling pathways. A better understanding of the relation between curcumin and microRNAs may provide a potential therapeutic target for various cancers.

Regulation of Bacteria-Induced Intercellular Adhesion Molecule-1 by CCAAT/Enhancer Binding Proteins

PubMed Central

Manzel, Lori J.; Chin, Cecilia L.; Behlke, Mark A.; Look, Dwight C.

2009-01-01

Direct interaction between bacteria and epithelial cells may initiate or amplify the airway response through induction of epithelial defense gene expression by nuclear factor-κB (NF-κB). However, multiple signaling pathways modify NF-κB effects to modulate gene expression. In this study, the effects of CCAAT/enhancer binding protein (C/EBP) family members on induction of the leukocyte adhesion glycoprotein intercellular adhesion molecule-1 (ICAM-1) was examined in primary cultures of human tracheobronchial epithelial cells incubated with nontypeable Haemophilus influenzae. Increased ICAM-1 gene transcription in response to H. influenzae required gene sequences located at −200 to −135 in the 5′-flanking region that contain a C/EBP-binding sequence immediately upstream of the NF-κB enhancer site. Constitutive C/EBPβ was found to have an important role in epithelial cell ICAM-1 regulation, while the adjacent NF-κB sequence binds the RelA/p65 and NF-κB1/p50 members of the NF-κB family to induce ICAM-1 expression in response to H. influenzae. The expression of C/EBP proteins is not regulated by p38 mitogen-activated protein kinase activation, but p38 affects gene transcription by increasing the binding of TATA-binding protein to TATA-box–containing gene sequences. Epithelial cell ICAM-1 expression in response to H. influenzae was decreased by expressing dominant-negative protein or RNA interference against C/EBPβ, confirming its role in ICAM-1 regulation. Although airway epithelial cells express multiple constitutive and inducible C/EBP family members that bind C/EBP sequences, the results indicate that C/EBPβ plays a central role in modulation of NF-κB–dependent defense gene expression in human airway epithelial cells after exposure to H. influenzae. PMID:18703796

Costimulatory molecule expression following exposure to orthopaedic implants wear debris.

PubMed

Bainbridge, J A; Revell, P A; Al-Saffar, N

2001-03-05

Patients with long-term orthopedic implants may develop inflammatory reactions due to the accumulation of biomaterial particles both around the implant and in distant organs. The exact impact of these particles on the normal immune cell function still remain relatively unclear. Activation of T-cells following exposure to biomaterial particles is driven by macrophages and requires synergistic signals primed by both antigen presentation and costimulation. The pattern of costimulatory molecule expression (CD80,CD86) was primarily examined using immunohistochemistry on tissue specimens of bone/implant interface membranes taken from sites of bone erosion. Additionally, costimulatory molecule expression was also assessed in the monocytic leukemia cell line U937 following exposure to clinically relevant titanium aluminum vanadium (TiAlV) and stainless steel particles (FeCrNi) cultured in vitro. This study demonstrates the induction and prominent expression of CD86 on almost all macrophage subsets at the bone/implant interface, including fused forms and large multinucleated giant cells (MNGC). In vitro analysis also indicated phagocytosis of metal particles by differentiated U937 caused significant induction of both CD80 and CD86 (p < 0.01), although the expression of CD86 dominated following prolonged exposure. The data presented highlights that CD86 is the predominant costimulatory molecule ligating to the complementary CD28 molecule at the inflammatory lesion of the interface. We propose that the intracellular presence of indigestible implant material, in addition to elevated costimulatory molecule expression, may promote T-cell inflammatory reactions at sites close to and distant from the orthopedic implant.

Src-like adaptor protein regulates TCR expression on thymocytes by linking the ubiquitin ligase c-Cbl to the TCR complex.

PubMed

Myers, Margaret D; Sosinowski, Tomasz; Dragone, Leonard L; White, Carmen; Band, Hamid; Gu, Hua; Weiss, Arthur

2006-01-01

The adaptor molecule SLAP and E3 ubiquitin ligase c-Cbl each regulate expression of T cell receptor (TCR)-CD3 on thymocytes. Here we provide genetic and biochemical evidence that both molecules function in the same pathway. TCR-CD3 expression was similar in the absence of SLAP and/or c-Cbl. SLAP and c-Cbl were found to interact, and their expression together downregulated CD3epsilon. This required multiple domains in SLAP and the ring finger of c-Cbl. Furthermore, expression of SLAP and c-Cbl together induced TCRzeta ubiquitination and degradation, preventing the accumulation of fully assembled recycling TCR complexes. These studies indicate that SLAP links the E3 ligase activity of c-Cbl to the TCR, allowing for stage-specific regulation of TCR expression.

A Clb/Cdk1-mediated regulation of Fkh2 synchronizes CLB expression in the budding yeast cell cycle.

PubMed

Linke, Christian; Chasapi, Anastasia; González-Novo, Alberto; Al Sawad, Istabrak; Tognetti, Silvia; Klipp, Edda; Loog, Mart; Krobitsch, Sylvia; Posas, Francesc; Xenarios, Ioannis; Barberis, Matteo

2017-01-01

Precise timing of cell division is achieved by coupling waves of cyclin-dependent kinase (Cdk) activity with a transcriptional oscillator throughout cell cycle progression. Although details of transcription of cyclin genes are known, it is unclear which is the transcriptional cascade that modulates their expression in a timely fashion. Here, we demonstrate that a Clb/Cdk1-mediated regulation of the Fkh2 transcription factor synchronizes the temporal mitotic CLB expression in budding yeast. A simplified kinetic model of the cyclin/Cdk network predicts a linear cascade where a Clb/Cdk1-mediated regulation of an activator molecule drives CLB3 and CLB2 expression. Experimental validation highlights Fkh2 as modulator of CLB3 transcript levels, besides its role in regulating CLB2 expression. A Boolean model based on the minimal number of interactions needed to capture the information flow of the Clb/Cdk1 network supports the role of an activator molecule in the sequential activation, and oscillatory behavior, of mitotic Clb cyclins. This work illustrates how transcription and phosphorylation networks can be coupled by a Clb/Cdk1-mediated regulation that synchronizes them.

p38 Mitogen-Activated Protein Kinase/Signal Transducer and Activator of Transcription-3 Pathway Signaling Regulates Expression of Inhibitory Molecules in T Cells Activated by HIV-1–Exposed Dendritic Cells

PubMed Central

Che, Karlhans Fru; Shankar, Esaki Muthu; Muthu, Sundaram; Zandi, Sasan; Sigvardsson, Mikael; Hinkula, Jorma; Messmer, Davorka; Larsson, Marie

2012-01-01

Human immunodeficiency virus type 1 (HIV-1) infection enhances the expression of inhibitory molecules on T cells, leading to T-cell impairment. The signaling pathways underlying the regulation of inhibitory molecules and subsequent onset of T-cell impairment remain elusive. We showed that both autologous and allogeneic T cells exposed to HIV-pulsed dendritic cells (DCs) upregulated cytotoxic T-lymphocyte antigen (CTLA-4), tumor-necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), lymphocyte-activation gene-3 (LAG3), T-cell immunoglobulin mucin-3 (TIM-3), CD160 and certain suppression-associated transcription factors, such as B-lymphocyte induced maturation protein-1 (BLIMP-1), deltex homolog 1 protein (DTX1) and forkhead box P3 (FOXP3), leading to T-cell suppression. This induction was regulated by p38 mitogen-activated protein kinase/signal transducer and activator of transcription-3 (P38MAPK/STAT3) pathways, because their blockade significantly abrogated expression of all the inhibitory molecules studied and a subsequent recovery in T-cell proliferation. Neither interleukin-6 (IL-6) nor IL-10 nor growth factors known to activate STAT3 signaling events were responsible for STAT3 activation. Involvement of the P38MAPK/STAT3 pathways was evident because these proteins had a higher level of phosphorylation in the HIV-1–primed cells. Furthermore, blockade of viral CD4 binding and fusion significantly reduced the negative effects DCs imposed on primed T cells. In conclusion, HIV-1 interaction with DCs modulated their functionality, causing them to trigger the activation of the P38MAPK/STAT3 pathway in T cells, which was responsible for the upregulation of inhibitory molecules. PMID:22777388

Dmrta1 regulates proneural gene expression downstream of Pax6 in the mammalian telencephalon.

PubMed

Kikkawa, Takako; Obayashi, Takeshi; Takahashi, Masanori; Fukuzaki-Dohi, Urara; Numayama-Tsuruta, Keiko; Osumi, Noriko

2013-08-01

The transcription factor Pax6 balances cell proliferation and neuronal differentiation in the mammalian developing neocortex by regulating the expression of target genes. Using microarray analysis, we observed the down-regulation of Dmrta1 (doublesex and mab-3-related transcription factor-like family A1) in the telencephalon of Pax6 homozygous mutant rats (rSey(2) /rSey(2) ). Dmrta1 expression was restricted to the neural stem/progenitor cells of the dorsal telencephalon. Overexpression of Dmrta1 induced the expression of the proneural gene Neurogenin2 (Neurog2) and conversely repressed Ascl1 (Mash1), a proneural gene expressed in the ventral telencephalon. We found that another Dmrt family molecule, Dmrt3, induced Neurog2 expression in the dorsal telencephalon. Our novel findings suggest that dual regulation of proneural genes mediated by Pax6 and Dmrt family members is crucial for cortical neurogenesis. © 2013 The Authors Genes to Cells © 2013 by the Molecular Biology Society of Japan and Wiley Publishing Asia Pty Ltd.

Conserved regulation of mesenchymal gene expression by Fgf-8 in face and limb development.

PubMed

Tucker, A S; Al Khamis, A; Ferguson, C A; Bach, I; Rosenfeld, M G; Sharpe, P T

1999-01-01

Clim-2 (NLI, Lbd1) is one of two related mouse proteins that interact with Lim-domain homeoproteins. In the mouse, embryonic expression of Clim-2 is particularly pronounced in facial ectomesenchyme and limb bud mesenchyme in association with Lim genes, Lhx-6 and Lmx-1 respectively. We show that in common with both these Lim genes, Clim-2 expression is regulated by signals from overlying epithelium. In both the developing face and the limb buds we identify Fgf-8 as the likely candidate signalling molecule that regulates Clim-2 expression. We show that in the mandibular arch, as in the limb, Fgf-8 functions in combination with CD44, a cell surface binding protein, and that blocking CD44 binding results in inhibition of Fgf8-induced expression of Clim-2 and Lhx-6. Regulation of gene expression by Fgf8 in association with CD44 is thus conserved between limb and mandibular arch development.

The coffee diterpene kahweol inhibits tumor necrosis factor-{alpha}-induced expression of cell adhesion molecules in human endothelial cells

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

Kim, Hyung Gyun; Kim, Ji Young; Hwang, Yong Pil

2006-12-15

Endothelial cells produce adhesion molecules after being stimulated with various inflammatory cytokines. These adhesion molecules play an important role in the development of atherogenesis. Recent studies have highlighted the chemoprotective and anti-inflammatory effects of kahweol, a coffee-specific diterpene. This study examined the effects of kahweol on the cytokine-induced monocyte/human endothelial cell interaction, which is a crucial early event in atherogenesis. Kahweol inhibited the adhesion of TNF{alpha}-induced monocytes to endothelial cells and suppressed the TNF{alpha}-induced protein and mRNA expression of the cell adhesion molecules, VCAM-1 and ICAM-1. Furthermore, kahweol inhibited the TNF{alpha}-induced JAK2-PI3K/Akt-NF-{kappa}B activation pathway in these cells. Overall, kahweol hasmore » anti-inflammatory and anti-atherosclerotic activities, which occurs partly by down-regulating the pathway that affects the expression and interaction of the cell adhesion molecules on endothelial cells.« less

Expression of adhesion molecules and cytokeratin 20 in merkel cell carcinomas.

PubMed

Tanaka, Yasushi; Sano, Toshiaki; Qian, Zhi Rong; Hirokawa, Mitsuyoshi

2004-01-01

Merkel cell carcinoma (MCC) is an aggressive neuroendocrine carcinoma of the skin. MCCs often show characteristic paranuclear dot-like immunopositivity for cytokeratin 20 (CK20), a globular aggregation of CK20 intermediate filaments. These aggregates typically form rhabdoid features and fibrous bodies and may be associated with a down-regulation in adhesion molecules (AMs). To date, the relationship between the expression of AMs and CK20 and clinicopathological findings in MCC has not been well examined. In this immunohistochemical study, we assessed the expression of AMs, CK20, and chromogranin A (CgA) on MCCs in 8 men and 23 women with this disease, and also characterized their clinicopathological features. This study is the largest of its kind that has been undertaken to date in Japanese patients. Compared to normal tissue, E-cadherin and alpha- and beta-catenins showed reduced membranous expression in 95.7%, 46.7%, and 45.2% of MCCs, respectively. Nuclear E-cadherin localization was seen in four tumors, all of which predominantly showed a CK20 dot pattern. However, there was no significant relationship between the membranous expression of AMs and a CK20 dot pattern. E-cadherin expression was significantly lower in tumors of > or =2 cm, and tumors negative for E-cadherin more frequently developed outside of the head and neck than within those regions. CgA was more intensely expressed in tumors with uniform nuclei and a dense lymphocytic infiltrate than in those that showed pleomorphisms and that had few, if any, infiltrating lymphocytes. These findings suggest that MCCs have a reduced expression of AMs and that down-regulation of E-cadherin expression may correlate with increased tumor aggressiveness. The fact that no significant relationship was demonstrable between the membranous expression of AMs and the CK20 expression pattern suggests that the mechanism of aggregation of intermediate filaments may be different in different types of tumors.

Myostatin signaling regulates Akt activity via the regulation of miR-486 expression.

PubMed

Hitachi, Keisuke; Nakatani, Masashi; Tsuchida, Kunihiro

2014-02-01

Myostatin, also known as growth and differentiation factor-8, is a pivotal negative regulator of skeletal muscle mass and reduces muscle protein synthesis by inhibiting the insulin-like growth factor-1 (IGF-1)/Akt/mammalian target of rapamycin (mTOR) pathway. However, the precise mechanism by which myostatin inhibits the IGF-1/Akt/mTOR pathway remains unclear. In this study, we investigated the global microRNA expression profile in myostatin knockout mice and identified miR-486, a positive regulator of the IGF-1/Akt pathway, as a novel target of myostatin signaling. In myostatin knockout mice, the expression level of miR-486 in skeletal muscle was significantly increased. In addition, we observed increased expression of the primary transcript of miR-486 (pri-miR-486) and Ankyrin 1.5 (Ank1.5), the host gene of miR-486, in myostatin knockout mice. In C2C12 cells, myostatin negatively regulated the expression of Ank1.5. Moreover, canonical myostatin signaling repressed the skeletal muscle-specific promoter activity of miR-486/Ank1.5. This repression was partially mediated by the E-box elements in the proximal region of the promoter. We also show that overexpression of miR-486 induced myotube hypertrophy in vitro and that miR-486 was essential to maintain skeletal muscle size both in vitro and in vivo. In addition, inhibition of miR-486 led to a decrease in Akt activity in C2C12 myotubes. Our findings indicate that miR-486 is one of the intermediary molecules connecting myostatin signaling and the IGF-1/Akt/mTOR pathway in the regulation of skeletal muscle size. Copyright © 2013 Elsevier Ltd. All rights reserved.

Modulation of extracellular matrix/adhesion molecule expression by BRG1 is associated with increased melanoma invasiveness.

PubMed

Saladi, Srinivas Vinod; Keenen, Bridget; Marathe, Himangi G; Qi, Huiling; Chin, Khew-Voon; de la Serna, Ivana L

2010-10-22

Metastatic melanoma is an aggressive malignancy that is resistant to therapy and has a poor prognosis. The progression of primary melanoma to metastatic disease is a multi-step process that requires dynamic regulation of gene expression through currently uncharacterized epigenetic mechanisms. Epigenetic regulation of gene expression often involves changes in chromatin structure that are catalyzed by chromatin remodeling enzymes. Understanding the mechanisms involved in the regulation of gene expression during metastasis is important for developing an effective strategy to treat metastatic melanoma. SWI/SNF enzymes are multisubunit complexes that contain either BRG1 or BRM as the catalytic subunit. We previously demonstrated that heterogeneous SWI/SNF complexes containing either BRG1 or BRM are epigenetic modulators that regulate important aspects of the melanoma phenotype and are required for melanoma tumorigenicity in vitro. To characterize BRG1 expression during melanoma progression, we assayed expression of BRG1 in patient derived normal skin and in melanoma specimen. BRG1 mRNA levels were significantly higher in stage IV melanomas compared to stage III tumors and to normal skin. To determine the role of BRG1 in regulating the expression of genes involved in melanoma metastasis, we expressed BRG1 in a melanoma cell line that lacks BRG1 expression and examined changes in extracellular matrix and adhesion molecule expression. We found that BRG1 modulated the expression of a subset of extracellular matrix remodeling enzymes and adhesion proteins. Furthermore, BRG1 altered melanoma adhesion to different extracellular matrix components. Expression of BRG1 in melanoma cells that lack BRG1 increased invasive ability while down-regulation of BRG1 inhibited invasive ability in vitro. Activation of metalloproteinase (MMP) 2 expression greatly contributed to the BRG1 induced increase in melanoma invasiveness. We found that BRG1 is recruited to the MMP2 promoter and

MicroRNA-8 promotes robust motor axon targeting by coordinate regulation of cell adhesion molecules during synapse development.

PubMed

Lu, Cecilia S; Zhai, Bo; Mauss, Alex; Landgraf, Matthias; Gygi, Stephen; Van Vactor, David

2014-09-26

Neuronal connectivity and specificity rely upon precise coordinated deployment of multiple cell-surface and secreted molecules. MicroRNAs have tremendous potential for shaping neural circuitry by fine-tuning the spatio-temporal expression of key synaptic effector molecules. The highly conserved microRNA miR-8 is required during late stages of neuromuscular synapse development in Drosophila. However, its role in initial synapse formation was previously unknown. Detailed analysis of synaptogenesis in this system now reveals that miR-8 is required at the earliest stages of muscle target contact by RP3 motor axons. We find that the localization of multiple synaptic cell adhesion molecules (CAMs) is dependent on the expression of miR-8, suggesting that miR-8 regulates the initial assembly of synaptic sites. Using stable isotope labelling in vivo and comparative mass spectrometry, we find that miR-8 is required for normal expression of multiple proteins, including the CAMs Fasciclin III (FasIII) and Neuroglian (Nrg). Genetic analysis suggests that Nrg and FasIII collaborate downstream of miR-8 to promote accurate target recognition. Unlike the function of miR-8 at mature larval neuromuscular junctions, at the embryonic stage we find that miR-8 controls key effectors on both sides of the synapse. MiR-8 controls multiple stages of synapse formation through the coordinate regulation of both pre- and postsynaptic cell adhesion proteins.

MicroRNA-8 promotes robust motor axon targeting by coordinate regulation of cell adhesion molecules during synapse development

PubMed Central

Lu, Cecilia S.; Zhai, Bo; Mauss, Alex; Landgraf, Matthias; Gygi, Stephen; Van Vactor, David

2014-01-01

Neuronal connectivity and specificity rely upon precise coordinated deployment of multiple cell-surface and secreted molecules. MicroRNAs have tremendous potential for shaping neural circuitry by fine-tuning the spatio-temporal expression of key synaptic effector molecules. The highly conserved microRNA miR-8 is required during late stages of neuromuscular synapse development in Drosophila. However, its role in initial synapse formation was previously unknown. Detailed analysis of synaptogenesis in this system now reveals that miR-8 is required at the earliest stages of muscle target contact by RP3 motor axons. We find that the localization of multiple synaptic cell adhesion molecules (CAMs) is dependent on the expression of miR-8, suggesting that miR-8 regulates the initial assembly of synaptic sites. Using stable isotope labelling in vivo and comparative mass spectrometry, we find that miR-8 is required for normal expression of multiple proteins, including the CAMs Fasciclin III (FasIII) and Neuroglian (Nrg). Genetic analysis suggests that Nrg and FasIII collaborate downstream of miR-8 to promote accurate target recognition. Unlike the function of miR-8 at mature larval neuromuscular junctions, at the embryonic stage we find that miR-8 controls key effectors on both sides of the synapse. MiR-8 controls multiple stages of synapse formation through the coordinate regulation of both pre- and postsynaptic cell adhesion proteins. PMID:25135978

[Down-regulatory effect of Nucleostemin expression on signal molecule of PI3K/AKT/mTOR pathway in HL-60 cells].

PubMed

Jia, Yu; Wei, Yuan-Yu; Zhang, Fan; Li, Zhao-Bo; Liu, Shuai; Yue, Bao-Hong

2014-02-01

This study was purpose to explore the down-regulatory effect of nucleostemin (NS) expression on signal molecules of PI3K/AKT/mTOR pathway belonged to candidate ways of p53-independent signal pathway in the leukemia cells. The expression of NS was interfered by using recombinant lentivirus expression vector NS-RNAi-GV248 to transfect HL-60 cells of p53 deficiency. The expression of NS and signal molecules of PI3K/AKT/mTOR pathway were detected by using Real-time PCR. The results of showed that the HL-60 cells were transfected by recombinant lentivirus vector NS-RNAi-GV248 successfully and with transfection rate up to 80%. According to results of Real-time PCR detection, the inhibition rate of NS gene was 56.5% in HL-60 cells. And the expression levels of PI3K,AKT and GβL mRNA (0.491 ± 0.084,0.398 ± 0.164, 0.472 ± 0.097 respectively) were obviously down-regulated by silencing NS, and showed statistical difference (P < 0.05) in comparison with control (1.002 ± 0.171, 1.000 ± 0.411, 1.001 ± 0.206 respectively) . It is concluded that the changes of signal molecules of PI3K/AKT/mTOR pathway positively correlate with NS down-regulation, which provides evidence for confirming PI3K/AKT/mTOR signal pathway possible as a type of NS p53-independent pathway.

Small and Smaller-sRNAs and MicroRNAs in the Regulation of Toxin Gene Expression in Prokaryotic Cells: A Mini-Review.

PubMed

Bloch, Sylwia; Węgrzyn, Alicja; Węgrzyn, Grzegorz; Nejman-Faleńczyk, Bożena

2017-05-30

Non-coding small RNAs (sRNAs) have been identified in the wide range of bacteria (also pathogenic species) and found to play an important role in the regulation of many processes, including toxin gene expression. The best characterized prokaryotic sRNAs regulate gene expression by base pairing with mRNA targets and fall into two broad classes: cis -encoded sRNAs (also called antisense RNA) and trans -acting sRNAs. Molecules from the second class are frequently considered as the most related to eukaryotic microRNAs. Interestingly, typical microRNA-size RNA molecules have also been reported in prokaryotic cells, although they have received little attention up to now. In this work we have collected information about all three types of small prokaryotic RNAs in the context of the regulation of toxin gene expression.

Generation of small molecules to interfere with regulated necrosis.

PubMed

Degterev, Alexei; Linkermann, Andreas

2016-06-01

Interference with regulated necrosis for clinical purposes carries broad therapeutic relevance and, if successfully achieved, has a potential to revolutionize everyday clinical routine. Necrosis was interpreted as something that no clinician might ever be able to prevent due to the unregulated nature of this form of cell death. However, given our growing understanding of the existence of regulated forms of necrosis and the roles of key enzymes of these pathways, e.g., kinases, peroxidases, etc., the possibility emerges to identify efficient and selective small molecule inhibitors of pathologic necrosis. Here, we review the published literature on small molecule inhibition of regulated necrosis and provide an outlook on how combination therapy may be most effective in treatment of necrosis-associated clinical situations like stroke, myocardial infarction, sepsis, cancer and solid organ transplantation.

PD-1 ligand expression by human colonic myofibroblasts/fibroblasts regulates CD4+ T-cell activity.

PubMed

Pinchuk, Irina V; Saada, Jamal I; Beswick, Ellen J; Boya, Gushyalatha; Qiu, Sumin M; Mifflin, Randy C; Raju, Gottumukkala S; Reyes, Victor E; Powell, Don W

2008-10-01

A prominent role for inhibitory molecules PD-L1 and PD-L2 in peripheral tolerance has been proposed. However, the phenotype and function of PD-L-expressing cells in human gut remains unclear. Recent studies suggest that colonic myofibroblasts (CMFs) and fibroblasts are important in the switch from acute inflammation to adaptive immunity. In the normal human colon, CMFs represent a distinct population of major histocompatibility complex class II(+) cells involved in the regulation of mucosal CD4(+) T-cell responses. PD-L1 and PD-L2 expression on human CMFs was determined using Western blot, fluorescence-activated cell sorter analysis and confocal microscopy. Lymphoproliferation assays and cytokine enzyme-linked immunosorbent assays were used to evaluate the role of B7 costimulators expressed by CMFs with regard to the regulation of preactivated T-helper cell responses. We demonstrate here the expression of PD-L1/2 molecules by normal human CMF and fibroblasts in situ and in culture. Both molecules support suppressive functions of CMFs in the regulation of activated CD4(+) T-helper cell proliferative responses; blocking this interaction reverses the suppressive effect of CMFs on T-cell proliferation and leads to increased production of the major T-cell growth factor, interleukin (IL)-2. PD-L1/2-mediated CMF suppressive functions are mainly due to the inhibition of IL-2 production, because supplementation of the coculture media with exogenous IL-2 led to partial recovery of activated T-cell proliferation. Our data suggest that stromal myofibroblasts and fibroblasts may limit T-helper cell proliferative activity in the gut and, thus, might play a prominent role in mucosal intestinal tolerance.

Expression of adhesion molecules, chemokines and matrix metallo- proteinases (MMPs) in viable and degenerating stage of Taenia solium metacestode in swine neurocysticercosis.

PubMed

Singh, Satyendra K; Singh, Aloukick K; Prasad, Kashi N; Singh, Amrita; Singh, Avinash; Rai, Ravi P; Tripathi, Mukesh; Gupta, Rakesh K; Husain, Nuzhat

2015-11-30

Neurocysticercosis (NCC) is a parasitic infection of central nervous system (CNS). Expression of adhesion molecules, chemokines and matrix metalloproteinases (MMPs) were investigated on brain tissues surrounding viable (n=15) and degenerating cysticerci (n=15) of Taenia solium in swine by real-time RT-PCR and ELISA. Gelatin gel zymography was performed for MMPs activity. ICAM-1 (intercellular adhesion molecule-1), E-selectin, MIP-1α (macrophage inflammatory protein-1α), Eotaxin-1 and RANTES (regulated on activation, normal T cell expressed and secreted) were associated with degenerating cysticerci (cysts). However, VCAM-1 (vascular cell adhesion molecule-1), MCP-1 (monocyte chemotactic protein-1), MMP-2 and MMP-9 were associated with both viable and degenerating cysts. In conclusion, viable and degenerating cysticerci have different immune molecule profiles and role of these molecules in disease pathogenesis needs to be investigated. Copyright © 2015 Elsevier B.V. All rights reserved.

Cell-type-specific expression of neural cell adhesion molecule (N-CAM) in Ito cells of rat liver. Up-regulation during in vitro activation and in hepatic tissue repair.

PubMed

Knittel, T; Aurisch, S; Neubauer, K; Eichhorst, S; Ramadori, G

1996-08-01

Ito cells (lipocytes, stellate cells) are regarded as the principle matrix-producing cell of the liver and have been shown recently to express glial fibrillary acidic protein, an intermediate filament typically found in glia cells of the nervous system. The present study examines 1) whether Ito cells of rat liver express central nervous system typical adhesion molecules, namely, neural cell adhesion molecule (N-CAM), in a cell-type-specific manner and 2) whether N-CAM expression is affected by activation of Ito cells in vitro and during rat liver injury in vivo. As assessed by reverse transcriptase polymerase chain reaction, Northern blotting, Western blotting, and immunocytochemistry of freshly isolated and cultivated hepatic cells, N-CAM expression was restricted to Ito cells and was absent in hepatocytes, Kupffer cells, and sinusoidal endothelial cells. Ito cells expressed predominantly N-CAM-coding transcripts of 6.1 and 4.8 kb in size and 140-kd isoforms of the N-CAM protein, which was localized on the cell surface membrane of Ito cells. In parallel to glial fibrillary acidic protein down-regulation and smooth muscle alpha-actin up-regulation, N-CAM expression was increased during in vitro transformation of Ito cells from resting to activated (myofibroblast-like) cells and by the fibrogenic mediator transforming growth factor-beta 1. By immunohistochemistry, N-CAM was detected in normal rat liver in the portal field as densely packed material and in a spot as well as fiber-like pattern probably representing nerve structures. However, after liver injury, N-CAM expression became detectable in mesenchymal cells within and around the necrotic area and within fibrotic septae. In serially cut tissue sections, N-CAM-positive cells were predominantly co-distributed with smooth muscle alpha-actin-positive cells rather than glial fibrillary acidic protein-positive cells, especially in fibrotic livers. The experimental results illustrate that N-CAM positivity in the

Synemin acts as a regulator of signalling molecules during skeletal muscle hypertrophy.

PubMed

Li, Zhenlin; Parlakian, Ara; Coletti, Dario; Alonso-Martin, Sonia; Hourdé, Christophe; Joanne, Pierre; Gao-Li, Jacqueline; Blanc, Jocelyne; Ferry, Arnaud; Paulin, Denise; Xue, Zhigang; Agbulut, Onnik

2014-11-01

Synemin, a type IV intermediate filament (IF) protein, forms a bridge between IFs and cellular membranes. As an A-kinase-anchoring protein, it also provides temporal and spatial targeting of protein kinase A (PKA). However, little is known about its functional roles in either process. To better understand its functions in muscle tissue, we generated synemin-deficient (Synm(-) (/-)) mice. Synm(-) (/-) mice displayed normal development and fertility but showed a mild degeneration and regeneration phenotype in myofibres and defects in sarcolemma membranes. Following mechanical overload, Synm(-) (/-) mice muscles showed a higher hypertrophic capacity with increased maximal force and fatigue resistance compared with control mice. At the molecular level, increased remodelling capacity was accompanied by decreased myostatin (also known as GDF8) and atrogin (also known as FBXO32) expression, and increased follistatin expression. Furthermore, the activity of muscle-mass control molecules (the PKA RIIα subunit, p70S6K and CREB1) was increased in mutant mice. Finally, analysis of muscle satellite cell behaviour suggested that the absence of synemin could affect the balance between self-renewal and differentiation of these cells. Taken together, our results show that synemin is necessary to maintain membrane integrity and regulates signalling molecules during muscle hypertrophy. © 2014. Published by The Company of Biologists Ltd.

Small and Smaller—sRNAs and MicroRNAs in the Regulation of Toxin Gene Expression in Prokaryotic Cells: A Mini-Review

PubMed Central

Bloch, Sylwia; Węgrzyn, Alicja; Węgrzyn, Grzegorz; Nejman-Faleńczyk, Bożena

2017-01-01

Non-coding small RNAs (sRNAs) have been identified in the wide range of bacteria (also pathogenic species) and found to play an important role in the regulation of many processes, including toxin gene expression. The best characterized prokaryotic sRNAs regulate gene expression by base pairing with mRNA targets and fall into two broad classes: cis-encoded sRNAs (also called antisense RNA) and trans-acting sRNAs. Molecules from the second class are frequently considered as the most related to eukaryotic microRNAs. Interestingly, typical microRNA-size RNA molecules have also been reported in prokaryotic cells, although they have received little attention up to now. In this work we have collected information about all three types of small prokaryotic RNAs in the context of the regulation of toxin gene expression. PMID:28556797

Ablation of CD11c(hi) dendritic cells exacerbates Japanese encephalitis by regulating blood-brain barrier permeability and altering tight junction/adhesion molecules.

PubMed

Kim, Jin Hyoung; Hossain, Ferdaus Mohd Altaf; Patil, Ajit Mahadev; Choi, Jin Young; Kim, Seong Bum; Uyangaa, Erdenebelig; Park, Sang-Youel; Lee, John-Hwa; Kim, Bumseok; Kim, Koanhoi; Eo, Seong Kug

2016-10-01

Japanese encephalitis (JE), characterized by extensive neuroinflammation following infection with neurotropic JE virus (JEV), is becoming a leading cause of viral encephalitis due to rapid changes in climate and demography. The blood-brain barrier (BBB) plays an important role in restricting neuroinvasion of peripheral leukocytes and virus, thereby regulating the progression of viral encephalitis. In this study, we explored the role of CD11c(hi) dendritic cells (DCs) in regulating BBB integrity and JE progression using a conditional depletion model of CD11c(hi) DCs. Transient ablation of CD11c(hi) DCs resulted in markedly increased susceptibility to JE progression along with highly increased neuro-invasion of JEV. In addition, exacerbated JE progression in CD11c(hi) DC-ablated hosts was closely associated with increased expression of proinflammatory cytokines (IFN-β, IL-6, and TNF-α) and CC chemokines (CCL2, CCL3, CXCL2) in the brain. Moreover, our results revealed that the exacerbation of JE progression in CD11c(hi) DC-ablated hosts was correlated with enhanced BBB permeability and reduced expression of tight junction and adhesion molecules (claudin-5, ZO-1, occluding, JAMs). Ultimately, our data conclude that the ablation of CD11c(hi) DCs provided a subsidiary impact on BBB integrity and the expression of tight junction/adhesion molecules, thereby leading to exacerbated JE progression. These findings provide insight into the secondary role of CD11c(hi) DCs in JE progression through regulation of BBB integrity and the expression of tight junction/adhesion molecules. Copyright © 2016 Elsevier Ltd. All rights reserved.

Outer membrane protein A of Escherichia coli K1 selectively enhances the expression of intercellular adhesion molecule-1 in brain microvascular endothelial cells.

PubMed

Selvaraj, Suresh K; Periandythevar, Parameswaran; Prasadarao, Nemani V

2007-04-01

Escherichia coli K1 meningitis is a serious central nervous system disease with unchanged mortality and morbidity rates for last few decades. Intercellular adhesion molecule 1 (ICAM-1) is a cell adhesion molecule involved in leukocyte trafficking toward inflammatory stimuli at the vascular endothelium; however, the effect of E. coli invasion of endothelial cells on the expression of ICAM-1 is not known. We demonstrate here that E. coli K1 invasion of human brain microvascular endothelial cells (HBMEC) selectively up-regulates the expression of ICAM-1, which occurs only in HBMEC invaded by the bacteria. The interaction of outer membrane protein A (OmpA) of E. coli with its receptor, Ecgp, on HBMEC was critical for the up-regulation of ICAM-1 and was depend on PKC-alpha and PI3-kinase signaling. Of note, the E. coli-induced up-regulation of ICAM-1 was not due to the cytokines secreted by HBMEC upon bacterial infection. Activation of NF-kappaB was required for E. coli mediated expression of ICAM-1, which was significantly inhibited by over-expressing the dominant negative forms of PKC-alpha and p85 subunit of PI3-kinase. The increased expression of ICAM-1 also enhanced the binding of THP-1 cells to HBMEC. Taken together, these data suggest that localized increase in ICAM-1 expression in HBMEC invaded by E. coli requires a novel interaction between OmpA and its receptor, Ecgp.

HDL-transferred microRNA-223 regulates ICAM-1 expression in endothelial cells

PubMed Central

Tabet, Fatiha; Vickers, Kasey C.; Cuesta Torres, Luisa F.; Wiese, Carrie B.; Shoucri, Bassem M.; Lambert, Gilles; Catherinet, Claire; Prado-Lourenco, Leonel; Levin, Michael G.; Thacker, Seth; Sethupathy, Praveen; Barter, Philip J.; Remaley, Alan T.; Rye, Kerry-Anne

2014-01-01

High-density lipoproteins (HDL) have many biological functions, including reducing endothelial activation and adhesion molecule expression. We recently reported that HDL transport and deliver functional microRNAs (miRNA). Here we show that HDL suppresses expression of intercellular adhesion molecule 1 (ICAM-1) through the transfer of miR-223 to endothelial cells. After incubation of endothelial cells with HDL, mature miR-223 levels are significantly increased in endothelial cells and decreased on HDL. However, miR-223 is not transcribed in endothelial cells and is not increased in cells treated with HDL from miR-223−/− mice. HDL inhibit ICAM-1 protein levels, but not in cells pretreated with miR-223 inhibitors. ICAM-1 is a direct target of HDL-transferred miR-223 and this is the first example of an extracellular miRNA regulating gene expression in cells where it is not transcribed. Collectively, we demonstrate that HDL’s anti-inflammatory properties are conferred, in part, through HDL-miR-223 delivery and translational repression of ICAM-1 in endothelial cells. PMID:24576947

Urea uptake enhances barrier function and antimicrobial defense in humans by regulating epidermal gene expression

PubMed Central

Grether-Beck, Susanne; Felsner, Ingo; Brenden, Heidi; Kohne, Zippora; Majora, Marc; Marini, Alessandra; Jaenicke, Thomas; Rodriguez-Martin, Marina; Trullas, Carles; Hupe, Melanie; Elias, Peter M.; Krutmann, Jean

2012-01-01

Urea is an endogenous metabolite, known to enhance stratum corneum hydration. Yet, topical urea anecdotally also improves permeability barrier function, and it appears to exhibit antimicrobial activity. Hence, we hypothesized that urea is not merely a passive metabolite, but a small-molecule regulator of epidermal structure and function. In 21 human volunteers, topical urea improved barrier function in parallel with enhanced antimicrobial peptide (LL-37 and β-defensin-2) expression. Urea both stimulates expression of, and is transported into keratinocytes by two urea transporters, UT-A1 and UT-A2, and by aquaporin 3, 7 and 9. Inhibitors of these urea transporters block the downstream biological effects of urea, which include increased mRNA and protein levels for: (i) transglutaminase-1, involucrin, loricrin and filaggrin; (ii) epidermal lipid synthetic enzymes, and (iii) cathelicidin/LL-37 and β-defensin-2. Finally, we explored the potential clinical utility of urea, showing that topical urea applications normalized both barrier function and antimicrobial peptide expression in a murine model of atopic dermatitis (AD). Together, these results show that urea is a small-molecule regulator of epidermal permeability barrier function and antimicrobial peptide expression after transporter uptake, followed by gene regulatory activity in normal epidermis, with potential therapeutic applications in diseased skin. PMID:22418868

Heterogeneous expression and regulation of CD40 in human hepatocellular carcinoma.

PubMed

Holub, Margareta; Zakeri, Schaker M; Lichtenberger, Cornelia; Pammer, Johannes; Paolini, Pierre; Leifeld, Ludger; Rockenschaub, Susanne; Wolschek, Markus F; Steger, Günther; Willheim, Martin; Gangl, Alfred; Reinisch, Walter

2003-02-01

CD40, a member of the tumour necrosis factor receptor family, plays a major role in adaptive immune responses and contributes to cancer surveillance. Conflicting results have been reported recently on the expression and function of CD40 in carcinomas. The aim of the present study was to investigate the role of CD40 in human hepatoma. CD40 expression was examined in hepatomas and derived cell lines by immunohistochemistry, flow cytometry and reverse transcriptase polymerase chain reaction. We investigated in hepatoma cell lines the regulation of CD40 by pro-inflammatory cytokines and the effects of its ligation with soluble CD40L on the expression of co-stimulatory and pro-apoptotic cell-surface molecules and survival. CD40 was detected with a similar frequency of about 40% in hepatoma specimens and derived cell lines but not in normal hepatocytes. Tumour necrosis factor alpha and its combination with interferon gamma upregulated CD40 only in intrinsically positive cell lines. CD40 ligation had no effect on cell viability or surface expression of CD54, CD80, CD86 or CD95. CD40 is expressed variably in human hepatoma and enhanced by distinct pro-inflammatory cytokines. The lack of detectable effects of CD40 ligation does not support a major role of this molecule in hepatocellular carcinoma biology.

Cell Adhesion Molecule and Lymphocyte Activation Marker Expression during Experimental Vaginal Candidiasis

PubMed Central

Wormley, Floyd L.; Chaiban, Joseph; Fidel, Paul L.

2001-01-01

Cell-mediated immunity by Th1-type CD4+ T cells is the predominant host defense mechanism against mucosal candidiasis. However, studies using an estrogen-dependent murine model of vaginal candidiasis have demonstrated little to no change in resident vaginal T cells during infection and no systemic T-cell infiltration despite the presence of Candida-specific systemic Th1-type responses in infected mice. The present study was designed to further investigate these observations by characterizing T-cell activation and cell adhesion molecule expression during primary and secondary C. albicans vaginal infections. While flow cytometry analysis of activation markers showed some evidence for activation of CD3+ draining lymph node and/or vaginal lymphocytes during both primary and secondary vaginal Candida infection, CD3+ cells expressing the homing receptors and integrins α4β7, αM290β7, and α4β1 in draining lymph nodes of mice with primary and secondary infections were reduced compared to results for uninfected mice. At the local level, few vaginal lymphocytes expressed integrins, with only minor changes observed during both primary and secondary infections. On the other hand, immunohistochemical analysis of vaginal cell adhesion molecule expression showed increases in mucosal addressin cell adhesion molecule 1 and vascular cell adhesion molecule 1 expression during both primary and secondary infections. Altogether, these data suggest that although the vaginal tissue is permissive to cellular infiltration during a vaginal Candida infection, the reduced numbers of systemic cells expressing the reciprocal cellular adhesion molecules may preempt cellular infiltration, thereby limiting Candida-specific T-cell responses against infection. PMID:11447188

Mouse CD23 regulates monocyte activation through an interaction with the adhesion molecule CD11b/CD18.

PubMed

Lecoanet-Henchoz, S; Plater-Zyberk, C; Graber, P; Gretener, D; Aubry, J P; Conrad, D H; Bonnefoy, J Y

1997-09-01

CD23 is expressed on a variety of hemopoietic cells. Recently, we have reported that blocking CD23 interactions in a murine model of arthritis resulted in a marked improvement of disease severity. Here, we demonstrate that CD11b, the alpha chain of the beta 2 integrin adhesion molecule complex CD11b/CD18 expressed on monocytes interacts with CD23. Using a recombinant fusion protein (ZZ-CD23), murine CD23 was shown to bind to peritoneal macrophages and peripheral blood cells isolated from mice as well as the murine macrophage cell line, RAW. The interactions between mouse ZZ-CD23 and CD11b/CD18-expressing cells were significantly inhibited by anti-CD11b monoclonal antibodies. A functional consequence was then demonstrated by inducing an up-regulation of interleukin-6 (IL-6) production following ZZ-CD23 incubation with monocytes. The addition of Fab fragments generated from the monoclonal antibody CD11b impaired this cytokine production by 50%. Interestingly, a positive autocrine loop was identified as IL-6 was shown to increase CD23 binding to macrophages. These results demonstrate that similar to findings using human cells, murine CD23 binds to the surface adhesion molecule, CD11b, and these interactions regulate biological activities of murine myeloid cells.

A gene expression system offering multiple levels of regulation: the Dual Drug Control (DDC) system.

PubMed

Sudomoina, Marina; Latypova, Ekaterina; Favorova, Olga O; Golemis, Erica A; Serebriiskii, Ilya G

2004-04-29

Whether for cell culture studies of protein function, construction of mouse models to enable in vivo analysis of disease epidemiology, or ultimately gene therapy of human diseases, a critical enabling step is the ability to achieve finely controlled regulation of gene expression. Previous efforts to achieve this goal have explored inducible drug regulation of gene expression, and construction of synthetic promoters based on two-hybrid paradigms, among others. In this report, we describe the combination of dimerizer-regulated two-hybrid and tetracycline regulatory elements in an ordered cascade, placing expression of endpoint reporters under the control of two distinct drugs. In this Dual Drug Control (DDC) system, a first plasmid expresses fusion proteins to DBD and AD, which interact only in the presence of a small molecule dimerizer; a second plasmid encodes a cassette transcriptionally responsive to the first DBD, directing expression of the Tet-OFF protein; and a third plasmid encodes a reporter gene transcriptionally responsive to binding by Tet-OFF. We evaluate the dynamic range and specificity of this system in comparison to other available systems. This study demonstrates the feasibility of combining two discrete drug-regulated expression systems in a temporally sequential cascade, without loss of dynamic range of signal induction. The efficient layering of control levels allowed by this combination of elements provides the potential for the generation of complex control circuitry that may advance ability to regulate gene expression in vivo.

Dynamic expression patterns of ECM molecules in the developing mouse olfactory pathway

PubMed Central

Shay, Elaine L.; Greer, Charles A.; Treloar, Helen B.

2009-01-01

Olfactory sensory neuron (OSN) axons follow stereotypic spatio-temporal paths in the establishment of the olfactory pathway. Extracellular matrix (ECM) molecules are expressed early in the developing pathway and are proposed to have a role in its initial establishment. During later embryonic development, OSNs sort out and target specific glomeruli to form precise, complex topographic projections. We hypothesized that ECM cues may help to establish this complex topography. The aim of this study was to characterize expression of ECM molecules during the period of glomerulogenesis, when synaptic contacts are forming. We examined expression of laminin-1, perlecan, tenascin-C and CSPGs and found a coordinated pattern of expression of these cues in the pathway. These appear to restrict axons to the pathway while promoting axon outgrowth within. Thus, ECM molecules are present in dynamic spatio-temporal positions to affect OSN axons as they navigate to the olfactory bulb and establish synapses. PMID:18570250

Energy Balance Regulating Neuropeptides Are Expressed through Pregnancy and Regulated by Interleukin-6 Deficiency in Mouse Placenta.

PubMed

Pazos, Patricia; Lima, Luis; Diéguez, Carlos; García, María C

2014-01-01

The placenta produces a number of signaling molecules including metabolic and reproductive hormones as well as several inflammatory mediators. Among them, Interleukin-6 (IL-6), a well-known immune and metabolic regulator, acts peripherally modulating metabolic function and centrally increasing energy expenditure and reducing body fat. IL-6 interacts with key hypothalamic neuropeptidergic systems controlling energy homeostasis such as those producing the orexigenic/anabolic: neuropeptide Y (NPY) and agouti-related peptide (AgRP) and anorectic/catabolic neuropeptides: proopiomelanocortin (POMC) and cocaine and amphetamine regulated transcript (CART). Human and rat placenta have been identified as source of these neuropeptides, but their expression and regulation in murine placental tissues remain unknown. Therefore, placental mRNA levels of IL-6, NPY, AgRP, POMC, and CART at different pregnancy stages (gestational days 13, 15, and 18) were analyzed by real time PCR, as were the effect of IL-6 deficiency (IL-6 knockout mice) on their placental expression. Our results showed that placenta-derived neuropeptides were regulated by gestational age and IL-6 throughout the second half of mouse pregnancy. These data suggest that IL-6 may participate in the fine tune control of energy balance during pregnancy by extending its action as a metabolic signal to the main organ at the fetomaternal interface: the placenta.

Energy Balance Regulating Neuropeptides Are Expressed through Pregnancy and Regulated by Interleukin-6 Deficiency in Mouse Placenta

PubMed Central

Pazos, Patricia; Lima, Luis; Diéguez, Carlos; García, María C.

2014-01-01

The placenta produces a number of signaling molecules including metabolic and reproductive hormones as well as several inflammatory mediators. Among them, Interleukin-6 (IL-6), a well-known immune and metabolic regulator, acts peripherally modulating metabolic function and centrally increasing energy expenditure and reducing body fat. IL-6 interacts with key hypothalamic neuropeptidergic systems controlling energy homeostasis such as those producing the orexigenic/anabolic: neuropeptide Y (NPY) and agouti-related peptide (AgRP) and anorectic/catabolic neuropeptides: proopiomelanocortin (POMC) and cocaine and amphetamine regulated transcript (CART). Human and rat placenta have been identified as source of these neuropeptides, but their expression and regulation in murine placental tissues remain unknown. Therefore, placental mRNA levels of IL-6, NPY, AgRP, POMC, and CART at different pregnancy stages (gestational days 13, 15, and 18) were analyzed by real time PCR, as were the effect of IL-6 deficiency (IL-6 knockout mice) on their placental expression. Our results showed that placenta-derived neuropeptides were regulated by gestational age and IL-6 throughout the second half of mouse pregnancy. These data suggest that IL-6 may participate in the fine tune control of energy balance during pregnancy by extending its action as a metabolic signal to the main organ at the fetomaternal interface: the placenta. PMID:24744782

Postnatal expression and androgen regulation of HOXBES2 homeoprotein in rat epididymis.

PubMed

Prabagaran, Esakki; Hegde, Uma C; Moodbidri, Sudhir B; Bandivdekar, Atmaram H; Raghavan, Vijaya P

2007-01-01

The multifunctional and androgen-regulated epididymis is known to provide a conducive microenvironment for the maturation and storage of mature spermatozoa. HOXB2 homeodomain-containing epididymis-specific sperm protein (HOXBES2), a molecule first reported by our group, exhibits cell- and region-specific expression. It was found in the cytoplasm of the principal epithelial cells with maximum in the distal segments of the rat epididymis. The present study was undertaken to determine whether HOXBES2 expression is regulated by androgens and postnatal epididymal development. Toward this, the epididymis was disallowed access to circulating androgens either by chemical or biologic castration. In bilaterally orchidectomized animals, the levels of immunoreactive HOXBES2 declined to <5 % of those seen in sham-operated animals. Exogenous dihydrotestosterone (DHT) supplementation (250 microg/kg body weight) for 7 days restored the expression levels to >or= 90 % of that observed in intact animals. Ethylene dimethane sulfonate (EDS) administration completely abolished HOXBES2 expression in the epididymis, and supplementation with DHT or DHT + estradiol for 10 days re-established HOXBES2 expression to near normalcy. However, in the estradiol alone-supplemented EDS-treated group, HOXBES2 remained undetected. The unaltered HOXBES2 expression following efferent duct ligation suggested that HOXBES2 is not critically dependent on testicular factors. During postnatal development, protein expression in the epididymis begins to appear from day 40 and 50 and increased from day 60 onward, coinciding with the mature levels of circulating androgens and the well-differentiated epididymis. Thus, the data obtained from this study suggests that HOXBES2 expression could be regulated by androgens, and its expression level is closely associated with the postnatal development of the epididymis.

Selective loss of mouse embryos due to the expression of transgenic major histocompatibility class I molecules early in embryogenesis.

PubMed

Aït-Azzouzene, D; Langkopf, A; Cohen, J; Bleux, C; Gendron, M C; Kanellopoulos-Langevin, C

1998-05-01

Among the numerous hypotheses proposed to explain the absence of fetal rejection by the mother in mammals, it has been suggested that regulation of expression of the polymorphic major histocompatibility complex (MHC) at the fetal-maternal interface plays a major role. In addition to a lack of MHC gene expression in the placenta throughout gestation, the absence of polymorphic MHC molecules on the early embryo, as well as their low level of expression after midgestation, could contribute to this important biologic phenomenon. In order to test this hypothesis, we have produced transgenic mice able to express polymorphic MHC class I molecules early in embryogenesis. We have placed the MHC class la gene H-2Kb under the control of a housekeeping gene promoter, the hydroxy-methyl-glutaryl coenzyme A reductase (HMG) gene minimal promoter. This construct has been tested for functionality after transfection into mouse fibroblast L cells. The analysis of three founder transgenic mice and their progeny suggested that fetoplacental units that could express the H-2Kb heavy chains are unable to survive in utero beyond midgestation. We have shown further that a much higher resorption rate, on days 11 to 13 of embryonic development, is observed among transgenic embryos developing from eggs microinjected at the one-cell stage with the pHMG-Kb construct than in control embryos. This lethality is not due to immune phenomena, since it is observed in histocompatible combinations between mother and fetus. These results are discussed in the context of what is currently known about the regulation of MHC expression at the fetal-maternal interface and in various transgenic mouse models.

Increase in the adhesion molecule P-selectin in endothelium overlying atherosclerotic plaques. Coexpression with intercellular adhesion molecule-1.

PubMed Central

Johnson-Tidey, R. R.; McGregor, J. L.; Taylor, P. R.; Poston, R. N.

1994-01-01

P-selectin (GMP-140) is an adhesion molecule present within endothelial cells that is rapidly translocated to the cell membrane upon activation, where it mediates endothelial-leukocyte interactions. Immunohistochemical analysis of human atherosclerotic plaques has shown strong expression of P-selectin by the endothelium overlying active atherosclerotic plaques. P-selectin is not, however, detected in normal arterial endothelium or in endothelium overlying inactive fibrous plaques. Color image analysis was used to quantitate the degree of P-selectin expression in the endothelium and demonstrates a statistically significant increase in P-selectin expression by atherosclerotic endothelial cells. Double immunofluorescence shows that some of this P-selectin is expressed on the luminal surface of the endothelial cells. Previous work has demonstrated a significant up-regulation in the expression of the intercellular adhesion molecule-1 in atherosclerotic endothelium and a study on the expression of intercellular adhesion molecule-1 and P-selectin in atherosclerosis shows a highly positive correlation. These results suggest that the selective and cooperative expression of P-selectin and intercellular adhesion molecule-1 may be involved in the recruitment of monocytes into sites of atherosclerosis. Images Figure 1 Figure 3 Figure 4 Figure 5 PMID:7513951

MicroRNAs: regulators of gene expression and cell differentiation

PubMed Central

Shivdasani, Ramesh A.

2006-01-01

The existence and roles of a class of abundant regulatory RNA molecules have recently come into sharp focus. Micro-RNAs (miRNAs) are small (approximately 22 bases), non–protein-coding RNAs that recognize target sequences of imperfect complementarity in cognate mRNAs and either destabilize them or inhibit protein translation. Although mechanisms of miRNA biogenesis have been elucidated in some detail, there is limited appreciation of their biological functions. Reported examples typically focus on miRNA regulation of a single tissue-restricted transcript, often one encoding a transcription factor, that controls a specific aspect of development, cell differentiation, or physiology. However, computational algorithms predict up to hundreds of putative targets for individual miRNAs, single transcripts may be regulated by multiple miRNAs, and miRNAs may either eliminate target gene expression or serve to finetune transcript and protein levels. Theoretical considerations and early experimental results hence suggest diverse roles for miRNAs as a class. One appealing possibility, that miRNAs eliminate low-level expression of unwanted genes and hence refine unilineage gene expression, may be especially amenable to evaluation in models of hematopoiesis. This review summarizes current understanding of miRNA mechanisms, outlines some of the important outstanding questions, and describes studies that attempt to define miRNA functions in hematopoiesis. PMID:16882713

Cell recognition molecule L1 promotes embryonic stem cell differentiation through the regulation of cell surface glycosylation

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

Li, Ying; Department of Clinical Laboratory, Second Affiliated Hospital of Dalian Medical University, Dalian 116023; Huang, Xiaohua

2013-10-25

Highlights: •Down-regulating FUT9 and ST3Gal4 expression blocks L1-induced neuronal differentiation of ESCs. •Up-regulating FUT9 and ST3Gal4 expression in L1-ESCs depends on the activation of PLCγ. •L1 promotes ESCs to differentiate into neuron through regulating cell surface glycosylation. -- Abstract: Cell recognition molecule L1 (CD171) plays an important role in neuronal survival, migration, differentiation, neurite outgrowth, myelination, synaptic plasticity and regeneration after injury. Our previous study has demonstrated that overexpressing L1 enhances cell survival and proliferation of mouse embryonic stem cells (ESCs) through promoting the expression of FUT9 and ST3Gal4, which upregulates cell surface sialylation and fucosylation. In the present study,more » we examined whether sialylation and fucosylation are involved in ESC differentiation through L1 signaling. RNA interference analysis showed that L1 enhanced differentiation of ESCs into neurons through the upregulation of FUT9 and ST3Gal4. Furthermore, blocking the phospholipase Cγ (PLCγ) signaling pathway with either a specific PLCγ inhibitor or knockdown PLCγ reduced the expression levels of both FUT9 and ST3Gal4 mRNAs and inhibited L1-mediated neuronal differentiation. These results demonstrate that L1 promotes neuronal differentiation from ESCs through the L1-mediated enhancement of FUT9 and ST3Gal4 expression.« less

Regulatory RNAs in Bacillus subtilis: a Gram-Positive Perspective on Bacterial RNA-Mediated Regulation of Gene Expression.

PubMed

Mars, Ruben A T; Nicolas, Pierre; Denham, Emma L; van Dijl, Jan Maarten

2016-12-01

Bacteria can employ widely diverse RNA molecules to regulate their gene expression. Such molecules include trans-acting small regulatory RNAs, antisense RNAs, and a variety of transcriptional attenuation mechanisms in the 5' untranslated region. Thus far, most regulatory RNA research has focused on Gram-negative bacteria, such as Escherichia coli and Salmonella. Hence, there is uncertainty about whether the resulting insights can be extrapolated directly to other bacteria, such as the Gram-positive soil bacterium Bacillus subtilis. A recent study identified 1,583 putative regulatory RNAs in B. subtilis, whose expression was assessed across 104 conditions. Here, we review the current understanding of RNA-based regulation in B. subtilis, and we categorize the newly identified putative regulatory RNAs on the basis of their conservation in other bacilli and the stability of their predicted secondary structures. Our present evaluation of the publicly available data indicates that RNA-mediated gene regulation in B. subtilis mostly involves elements at the 5' ends of mRNA molecules. These can include 5' secondary structure elements and metabolite-, tRNA-, or protein-binding sites. Importantly, sense-independent segments are identified as the most conserved and structured potential regulatory RNAs in B. subtilis. Altogether, the present survey provides many leads for the identification of new regulatory RNA functions in B. subtilis. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Regulatory RNAs in Bacillus subtilis: a Gram-Positive Perspective on Bacterial RNA-Mediated Regulation of Gene Expression

PubMed Central

Mars, Ruben A. T.; Nicolas, Pierre; Denham, Emma L.

2016-01-01

SUMMARY Bacteria can employ widely diverse RNA molecules to regulate their gene expression. Such molecules include trans-acting small regulatory RNAs, antisense RNAs, and a variety of transcriptional attenuation mechanisms in the 5′ untranslated region. Thus far, most regulatory RNA research has focused on Gram-negative bacteria, such as Escherichia coli and Salmonella. Hence, there is uncertainty about whether the resulting insights can be extrapolated directly to other bacteria, such as the Gram-positive soil bacterium Bacillus subtilis. A recent study identified 1,583 putative regulatory RNAs in B. subtilis, whose expression was assessed across 104 conditions. Here, we review the current understanding of RNA-based regulation in B. subtilis, and we categorize the newly identified putative regulatory RNAs on the basis of their conservation in other bacilli and the stability of their predicted secondary structures. Our present evaluation of the publicly available data indicates that RNA-mediated gene regulation in B. subtilis mostly involves elements at the 5′ ends of mRNA molecules. These can include 5′ secondary structure elements and metabolite-, tRNA-, or protein-binding sites. Importantly, sense-independent segments are identified as the most conserved and structured potential regulatory RNAs in B. subtilis. Altogether, the present survey provides many leads for the identification of new regulatory RNA functions in B. subtilis. PMID:27784798

The Drosophila cell adhesion molecule Neuroglian regulates Lissencephaly-1 localisation in circulating immunosurveillance cells.

PubMed

Williams, Michael J

2009-03-25

When the parasitoid wasp Leptopilina boulardi lays its eggs in Drosophila larvae phagocytic cells called plasmatocytes and specialized cells known as lamellocytes encapsulate the egg. This requires these circulating immunosurveillance cells (haemocytes) to change from a non-adhesive to an adhesive state enabling them to bind to the invader. Interestingly, attachment of leukocytes, platelets, and insect haemocytes requires the same adhesion complexes as epithelial and neuronal cells. Here evidence is presented showing that the Drosophila L1-type cell adhesion molecule Neuroglian (Nrg) is required for haemocytes to encapsulate L. boulardi wasp eggs. The amino acid sequence FIGQY containing a conserved phosphorylated tyrosine is found in the intracellular domain of all L1-type cell adhesion molecules. This conserved tyrosine is phosphorylated at the cell periphery of plasmatocytes and lamellocytes prior to parasitisation, but dephosphorylated after immune activation. Intriguingly, another pool of Nrg located near the nucleus of plasmatocytes remains phosphorylated after parasitisation. In mammalian neuronal cells phosphorylated neurofascin, another L1-type cell adhesion molecule interacts with a nucleokinesis complex containing the microtubule binding protein lissencephaly-1 (Lis1) 1. Interestingly in plasmatocytes from Nrg mutants the nucleokinesis regulating protein Lissencephaly-1 (Lis1) fails to localise properly around the nucleus and is instead found diffuse throughout the cytoplasm and at unidentified perinuclear structures. After attaching to the wasp egg control plasmatocytes extend filopodia laterally from their cell periphery; as well as extending lateral filopodia plasmatocytes from Nrg mutants also extend many filopodia from their apical surface. The Drosophila cellular adhesion molecule Neuroglian is expressed in haemocytes and its activity is required for the encapsulation of L. boularli eggs. At the cell periphery of haemocytes Neuroglian may be

The Drosophila cell adhesion molecule Neuroglian regulates Lissencephaly-1 localisation in circulating immunosurveillance cells

PubMed Central

Williams, Michael J

2009-01-01

Background When the parasitoid wasp Leptopilina boulardi lays its eggs in Drosophila larvae phagocytic cells called plasmatocytes and specialized cells known as lamellocytes encapsulate the egg. This requires these circulating immunosurveillance cells (haemocytes) to change from a non-adhesive to an adhesive state enabling them to bind to the invader. Interestingly, attachment of leukocytes, platelets, and insect haemocytes requires the same adhesion complexes as epithelial and neuronal cells. Results Here evidence is presented showing that the Drosophila L1-type cell adhesion molecule Neuroglian (Nrg) is required for haemocytes to encapsulate L. boulardi wasp eggs. The amino acid sequence FIGQY containing a conserved phosphorylated tyrosine is found in the intracellular domain of all L1-type cell adhesion molecules. This conserved tyrosine is phosphorylated at the cell periphery of plasmatocytes and lamellocytes prior to parasitisation, but dephosphorylated after immune activation. Intriguingly, another pool of Nrg located near the nucleus of plasmatocytes remains phosphorylated after parasitisation. In mammalian neuronal cells phosphorylated neurofascin, another L1-type cell adhesion molecule interacts with a nucleokinesis complex containing the microtubule binding protein lissencephaly-1 (Lis1) [1]. Interestingly in plasmatocytes from Nrg mutants the nucleokinesis regulating protein Lissencephaly-1 (Lis1) fails to localise properly around the nucleus and is instead found diffuse throughout the cytoplasm and at unidentified perinuclear structures. After attaching to the wasp egg control plasmatocytes extend filopodia laterally from their cell periphery; as well as extending lateral filopodia plasmatocytes from Nrg mutants also extend many filopodia from their apical surface. Conclusion The Drosophila cellular adhesion molecule Neuroglian is expressed in haemocytes and its activity is required for the encapsulation of L. boularli eggs. At the cell periphery of

Naringin suppress chondrosarcoma migration through inhibition vascular adhesion molecule-1 expression by modulating miR-126.

PubMed

Tan, Tzu-Wei; Chou, Ying-Erh; Yang, Wei-Hung; Hsu, Chin-Jung; Fong, Yi-Chin; Tang, Chih-Hsin

2014-09-01

Chondrosarcoma, a primary malignant bone cancer, has a potent capacity to invade locally and cause distant metastasis, especially to the lungs. Patients diagnosed with it have poor prognosis. Naringin, polymethoxylated flavonoid commonly found in citrus fruits, has anti-oxidant, anti-inflammatory and anti-tumor activity; whether naringin regulates migration of chondrosarcoma is largely unknown. Here we report that naringin does not expedite apoptosis in human chondrosarcoma. By contrast, at noncytotoxic concentrations, naringin suppressed migration and invasion of chondrosarcoma cells. Vascular cell adhesion molecule-1 (VCAM-1) of the immunoglobulin superfamily is linked with metastasis; we found incubation of chondrosarcoma cells with naringin reducing mRNA transcription for, and cell surface expression of, VCAM-1. We also observed that naringin enhancing miR-126 expression, and miR-126 inhibitor reversed the naringin-inhibited cell motility and VCAM-1 expression. Therefore, naringin inhibits migration and invasion of human chondrosarcoma via down-regulation of VCAM-1 by increasing miR-126. Thus, naringin may be a novel anti-migration agent for the treatment of migration in chondrosarcoma. Copyright © 2014 Elsevier B.V. All rights reserved.

Targeted expression of suicide gene by tissue-specific promoter and microRNA regulation for cancer gene therapy.

PubMed

Danda, Ravikanth; Krishnan, Gopinath; Ganapathy, Kalaivani; Krishnan, Uma Maheswari; Vikas, Khetan; Elchuri, Sailaja; Chatterjee, Nivedita; Krishnakumar, Subramanian

2013-01-01

In order to realise the full potential of cancer suicide gene therapy that allows the precise expression of suicide gene in cancer cells, we used a tissue specific Epithelial cell adhesion molecule (EpCAM) promoter (EGP-2) that directs transgene Herpes simplex virus-thymidine kinase (HSV-TK) expression preferentially in EpCAM over expressing cancer cells. EpCAM levels are considerably higher in retinoblastoma (RB), a childhood eye cancer with limited expression in normal cells. Use of miRNA regulation, adjacent to the use of the tissue-specific promoter, would provide the second layer of control to the transgene expression only in the tumor cells while sparing the normal cells. To test this hypothesis we cloned let-7b miRNA targets in the 3'UTR region of HSV-TK suicide gene driven by EpCAM promoter because let-7 family miRNAs, including let-7b, were found to be down regulated in the RB tumors and cell lines. We used EpCAM over expressing and let-7 down regulated RB cell lines Y79, WERI-Rb1 (EpCAM (+ve)/let-7b(down-regulated)), EpCAM down regulated, let-7 over expressing normal retinal Müller glial cell line MIO-M1(EpCAM (-ve)/let-7b(up-regulated)), and EpCAM up regulated, let-7b up-regulated normal thyroid cell line N-Thy-Ori-3.1(EpCAM (+ve)/let-7b(up-regulated)) in the study. The cell proliferation was measured by MTT assay, apoptosis was measured by probing cleaved Caspase3, EpCAM and TK expression were quantified by Western blot. Our results showed that the EGP2-promoter HSV-TK (EGP2-TK) construct with 2 or 4 copies of let-7b miRNA targets expressed TK gene only in Y79, WERI-Rb-1, while the TK gene did not express in MIO-M1. In summary, we have developed a tissue-specific, miRNA-regulated dual control vector, which selectively expresses the suicide gene in EpCAM over expressing cells.

Regulation of the human SLC25A20 expression by peroxisome proliferator-activated receptor alpha in human hepatoblastoma cells

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

Tachibana, Keisuke, E-mail: nya@phs.osaka-u.ac.jp; Takeuchi, Kentaro; Inada, Hirohiko

2009-11-20

Solute carrier family 25, member 20 (SLC25A20) is a key molecule that transfers acylcarnitine esters in exchange for free carnitine across the mitochondrial membrane in the mitochondrial {beta}-oxidation. The peroxisome proliferator-activated receptor alpha (PPAR{alpha}) is a ligand-activated transcription factor that plays an important role in the regulation of {beta}-oxidation. We previously established tetracycline-regulated human cell line that can be induced to express PPAR{alpha} and found that PPAR{alpha} induces the SLC25A20 expression. In this study, we analyzed the promoter region of the human slc25a20 gene and showed that PPAR{alpha} regulates the expression of human SLC25A20 via the peroxisome proliferator responsive element.

Mixed isotype class II antigen expression. A novel class II molecule is expressed on a murine B cell lymphoma

PubMed Central

1989-01-01

The structures of Ia molecules expressed by two BALB/c B cell lymphoma lines, A20-1.11 (A20) and 2PK3, were analyzed in an effort to explain the differences in antigen-presenting capacity displayed by these cells. Alloreactive T cell hybridomas specific for I-Ad and antigen- specific, I-Ad-restricted T cells responded well to A20 as the APC. The same alloreactive T cell hybridomas responded weakly or not at all to 2PK3 and the responses of the antigen-specific, I-Ad-restricted T cells were consistently lower to antigen presented by 2PK3 as compared with A20. T cells restricted to I-Ed responded equally well to either A20 or 2PK3 as APC. Additionally 2PK3, but not A20, stimulated a strong syngeneic mixed lymphocyte response. Structural analyses of the Ia antigens revealed that I-A and I-E molecules were expressed by A20, whereas an I-E and a novel I-A-like molecule were expressed by 2PK3. The novel class II molecule was affinity purified from 2PK3 cells using an mAb specific for Ad beta (MK-D6), and this molecule was subsequently shown by an RIA to react with an E alpha-specific mAb (14-4-4S) as well. Chain-specific polyclonal antisera raised against I-A and I-E alpha and beta chains indicated that the 2PK3 "I-A" alpha chain reacted in immunoblot with E alpha-specific and not A alpha-specific antisera, whereas the beta chain reacted with A beta- and not E beta-specific antisera. Peptide map and partial amino acid sequence analyses indicated that the "I-A" molecule expressed by 2PK3 represented a mixed isotype structure resulting from the pairing of Ed alpha with Ad beta. By immunofluorescence staining analysis, 2PK3 did not react with an mAb specific for Ad alpha. 2PK3 was capable of limited antigen presentation through the mixed isotype molecule to I-Ad-restricted OVA-specific T cell hybridomas, although the responses induced were low compared with presentation through I-A on A20. Previous descriptions of the expression of mixed isotype class II molecules in the

Notable Expressions: Transcriptional Regulation from Biochemistry to Immunology | Center for Cancer Research

Cancer.gov

Dinah Singer, Ph.D., came to NCI in 1975 as a Postdoctoral Fellow in the Laboratory of Biochemistry, but soon created a career for herself in the Experimental Immunology Branch. Her interest in how genes are regulated to control biological function led her to focus on major histocompatibility complex class I genes (MHC Class I)—molecules critical to immune system function—as a model system for complex regulation of ubiquitously expressed genes across cell types and molecular contexts. Using this system to study the sequence elements and factors that control transcription, her laboratory continues to uncover fundamental principles of gene regulation. In addition to her active research career, Singer has served since 1999 as Director of NCI’s Division of Cancer Biology, which manages a portfolio of over 2,200 grants to extramural investigators.

Regulation of Expressive Behavior as Reflecting Affect Socialization.

ERIC Educational Resources Information Center

Saarni, Carolyn

Regulated expressiveness (the modification of expressive behavior) is a complex phenomenon. Accomplished basically in four ways, regulated expressiveness has developmental dimensions, motivational precursors, and cognitive antecedents, including perspective-taking ability and the growth of self-awareness. Ability to regulate expressiveness appears…

Omentin inhibits TNF-{alpha}-induced expression of adhesion molecules in endothelial cells via ERK/NF-{kappa}B pathway

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

Zhong, Xia, E-mail: zhongxia1977@126.com; Li, Xiaonan; Liu, Fuli

2012-08-24

Highlights: Black-Right-Pointing-Pointer Omentin inhibited TNF-{alpha}-induced adhesion of THP-1 cells to HUVECs. Black-Right-Pointing-Pointer Omentin reduces expression of ICAM-1 and VCAM-1 induced by TNF-{alpha} in HUVECs. Black-Right-Pointing-Pointer Omentin inhibits TNF-{alpha}-induced ERK and NF-{kappa}B activation in HUVECs. Black-Right-Pointing-Pointer Omentin supreeses TNF-{alpha}-induced expression of ICAM-1 and VCAM-1 via ERK/NF-{kappa}B pathway. -- Abstract: In the present study, we investigated whether omentin affected the expression of intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in tumor necrosis factor-{alpha} (TNF-{alpha}) induced human umbilical vein endothelial cells (HUVECs). Our data showed that omentin decreased TNF-{alpha}-induced expression of ICAM-1 and VCAM-1 in HUVECs. In addition, omentin inhibitedmore » TNF-{alpha}-induced adhesion of THP-1 cells to HUVECs. Further, we found that omentin inhibited TNF-{alpha}-activated signal pathway of nuclear factor-{kappa}B (NF-{kappa}B) by preventing NF-{kappa}B inhibitory protein (I{kappa}B{alpha}) degradation and NF-{kappa}B/DNA binding activity. Omentin pretreatment significantly inhibited TNF-{alpha}-induced ERK activity and ERK phosphorylation in HUVECs. Pretreatment with PD98059 suppressed TNF-{alpha}-induced NF-{kappa}B activity. Omentin, NF-kB inhibitor (BAY11-7082) and ERK inhibitor (PD98059) reduced the up-regulation of ICAM-1 and VCAM-1 induced by TNF-{alpha}. These results suggest that omentin may inhibit TNF-{alpha}-induced expression of adhesion molecules in endothelial cells via blocking ERK/NF-{kappa}B pathway.« less

Ligand-regulated peptides: a general approach for modulating protein-peptide interactions with small molecules.

PubMed

Binkowski, Brock F; Miller, Russell A; Belshaw, Peter J

2005-07-01

We engineered a novel ligand-regulated peptide (LiRP) system where the binding activity of intracellular peptides is controlled by a cell-permeable small molecule. In the absence of ligand, peptides expressed as fusions in an FKBP-peptide-FRB-GST LiRP scaffold protein are free to interact with target proteins. In the presence of the ligand rapamycin, or the nonimmunosuppressive rapamycin derivative AP23102, the scaffold protein undergoes a conformational change that prevents the interaction of the peptide with the target protein. The modular design of the scaffold enables the creation of LiRPs through rational design or selection from combinatorial peptide libraries. Using these methods, we identified LiRPs that interact with three independent targets: retinoblastoma protein, c-Src, and the AMP-activated protein kinase. The LiRP system should provide a general method to temporally and spatially regulate protein function in cells and organisms.

Altered expression of junctional adhesion molecule 4 in injured podocytes.

PubMed

Harita, Yutaka; Miyauchi, Naoko; Karasawa, Tamaki; Suzuki, Koichi; Han, Gi Dong; Koike, Hiroko; Igarashi, Takashi; Shimizu, Fujio; Kawachi, Hiroshi

2006-02-01

Recent investigations have revealed the importance of glomerular podocytes with its diaphragm as the major filtration barrier. Junctional adhesion molecule 4 (JAM4) has been identified as a protein that interacts with membrane-associated guanyl kinase inverted (MAGI)-1 and is reported to be expressed on podocytes. To elucidate the role of JAM4 on podocytes, we examined the expression of JAM4 and MAGI-1 in normal and two different proteinuric rat models: puromycin aminonucleoside (PAN) nephropathy and anti-nephrin antibody-induced (ANA) nephropathy, one model with and one without effacement of podocyte foot processes. JAM4 was detected by immunomicroscopy at the apical membrane of normal podocytes. JAM4 immunostaining was focally increased in the podocytes in PAN nephropathy but not in ANA nephropathy. In proteinuric podocytes, the expression of JAM4 was distinct from that of MAGI-1 or other slit diaphragm molecules such as nephrin and ZO-1. Close colocalization of JAM4 and ezrin was maintained in PAN nephropathy. By immunoelectron microscopy, the signals for JAM4 were detected at the free apical membrane of the podocytes with effaced foot processes. Studies with selective detergent extract revealed that the subcellular localization of JAM4 was altered in PAN nephropathy. Thus the altered expression of JAM4 appears to be associated with morphological changes in podocytes and can be a useful marker of injured podocytes. JAM4 may have a different role at the apical membrane besides the role as a junctional molecule and is likely associated with the unique structure of this epithelium.

Aberrant expression of the tight junction molecules claudin-1 and zonula occludens-1 mediates cell growth and invasion in oral squamous cell carcinoma.

PubMed

Babkair, Hamzah; Yamazaki, Manabu; Uddin, Md Shihab; Maruyama, Satoshi; Abé, Tatsuya; Essa, Ahmed; Sumita, Yoshimasa; Ahsan, Md Shahidul; Swelam, Wael; Cheng, Jun; Saku, Takashi

2016-11-01

We reported that altered cell contact mediated by E-cadherin is an initial event in the pathogenesis of oral epithelial malignancies. To assess other effects of cell adhesion, we examined the expression levels of tight junction (TJ) molecules in oral carcinoma in situ (CIS) and squamous cell carcinoma (SCC). To identify changes in the expression of TJ molecules, we conducted an analysis of the immunohistochemical profiles of claudin-1 (CLDN-1) and zonula occludens-1 (ZO-1) in surgical specimens acquired from patients with oral SCC containing foci of epithelial dysplasia or from patients with CIS. We used immunofluorescence, Western blotting, reverse-transcription polymerase chain reaction, and RNA interference to evaluate the functions of CLDN-1 and ZO-1 in cultured oral SCC cells. TJ molecules were not detected in normal oral epithelial tissues but were expressed in SCC/CIS cells. ZO-1 was localized within the nucleus of proliferating cells. When CLDN-1 expression was inhibited by transfecting cells with specific small interference RNAs, SCC cells dissociated, and their ability to proliferate and invade Matrigel was inhibited. In contrast, although RNA interference-mediated inhibition of ZO-1 expression did not affect cell morphology, it inhibited cell proliferation and invasiveness. Our findings indicated that the detection of TJ molecules in the oral epithelia may serve as a marker for the malignant phenotype of cells in which CLDN-1 regulates proliferation and invasion. Copyright © 2016 Elsevier Inc. All rights reserved.

Ethanol extracts of black pepper or turmeric down-regulated SIRT1 protein expression in Daudi culture cells.

PubMed

Nishimura, Yuri; Kitagishi, Yasuko; Yoshida, Hitomi; Okumura, Naoko; Matsuda, Satoru

2011-01-01

SIRT1 is a mammalian candidate molecule involved in longevity and diverse metabolic processes. The present study aimed to determine the effects of certain herbs and spices on SIRT1 expression. Human cell lines Daudi, Jurkat, U937 and K562 were cultured in RPMI-1640. Herb and spice powders were prepared and the supernatants were collected. RT-PCR was used to quantify the expression level of the gene. Protein samples were then analyzed by Western blotting. Western blotting revealed the down-regulation of SIRT1 protein expression in Daudi cells treated with extracts of black pepper or turmeric. On the other hand, the effect on the SIRT1 gene expression examined by reverse transcription polymerase chain reaction was unaltered. In conclusion, component(s) of certain herbs and spices may induce the down-regulation of SIRT1 protein.

Aflatoxin B1 affects apoptosis and expression of death receptor and endoplasmic reticulum molecules in chicken spleen.

PubMed

Zhu, Panpan; Zuo, Zhicai; Zheng, Zhixiang; Wang, Fengyuan; Peng, Xi; Fang, Jing; Cui, Hengmin; Gao, Caixia; Song, Hetao; Zhou, Yi; Liu, Xici

2017-11-21

Aflatoxin B 1 (AFB 1 ) is a natural product of the Aspergillus genus of molds, which grow on several foodstuffs stored in hot moist conditions, and is among the most potent hepatocarcinogens and immunosuppression presently known. The latter was related to the up-regulated apoptosis of immune organs. However, the effect of expression of death receptor and endoplasmic reticulum molecules in AFB 1 -induced apoptosis of chicken splenocytes was largely unknown. The objective of this study was to investigate this unknown field. One hundred and forty four one-day-old chickens were randomly divided into control group (0 mg/kg AFB 1 ) and AFB 1 group (0.6 mg/kg AFB 1 ), respectively and fed with AFB 1 for 21 days. Histological observation demonstrated that AFB 1 caused slight congestion and lymphocytic depletion in the spleen. TUNEL and flow cytometry assays showed the excessive apoptosis of splenocytes provoked by AFB 1 . Moreover, quantitative real-time PCR analysis revealed that AFB 1 induced the elevated mRNA expression of Fas, FasL, TNF-α, TNF-R 1 , Caspase-3, Caspase-8, Caspase-10, Grp78 and Grp94 in the spleen. These findings suggested that AFB 1 could lead the excessive apoptosis and alter the expression of death receptor and endoplasmic reticulum molecules in chicken spleen.

Cells differentiated from mouse embryonic stem cells via embryoid bodies express renal marker molecules.

PubMed

Kramer, Jan; Steinhoff, Jürgen; Klinger, Matthias; Fricke, Lutz; Rohwedel, Jürgen

2006-03-01

Differentiation of mouse embryonic stem (ES) cells via embryoid bodies (EB) is established as a suitable model to study cellular processes of development in vitro. ES cells are known to be pluripotent because of their capability to differentiate into cell types of all three germ layers including germ cells. Here, we show that ES cells differentiate into renal cell types in vitro. We found that genes were expressed during EB cultivation, which have been previously described to be involved in renal development. Marker molecules characteristic for terminally differentiated renal cell types were found to be expressed predominantly during late stages of EB cultivation, while marker molecules involved in the initiation of nephrogenesis were already expressed during early steps of EB development. On the cellular level--using immunostaining--we detected cells expressing podocin, nephrin and wt-1, characteristic for differentiated podocytes and other cells, which expressed Tamm-Horsfall protein, a marker for distal tubule epithelial cells of kidney tissue. Furthermore, the proximal tubule marker molecules renal-specific oxido reductase, kidney androgen-related protein and 25-hydroxyvitamin D3alpha-hydroxylase were found to be expressed in EBs. In particular, we could demonstrate that cells expressing podocyte marker molecules assemble to distinct ring-like structures within the EBs. Because the differentiation efficiency into these cell types is still relatively low, application of fibroblast growth factor (FGF)-2 in combination with leukaemia inhibitory factor was tested for induction, but did not enhance ES cell-derived renal differentiation in vitro.

Nutlin-3 down-regulates retinoblastoma protein expression and inhibits muscle cell differentiation

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

Walsh, Erica M.; Niu, MengMeng; Bergholz, Johann

The p53 tumor suppressor gene plays a critical role in regulation of proliferation, cell death and differentiation. The MDM2 oncoprotein is a major negative regulator for p53 by binding to and targeting p53 for proteasome-mediated degradation. The small molecule inhibitor, nutlin-3, disrupts MDM2-p53 interaction resulting in stabilization and activation of p53 protein. We have previously shown that nutlin-3 activates p53, leading to MDM2 accumulation as concomitant of reduced retinoblastoma (Rb) protein stability. It is well known that Rb is important in muscle development and myoblast differentiation and that rhabdomyosarcoma (RMS), or cancer of the skeletal muscle, typically harbors MDM2 amplification.more » In this study, we show that nutlin-3 inhibited myoblast proliferation and effectively prevented myoblast differentiation, as evidenced by lack of expression of muscle differentiation markers including myogenin and myosin heavy chain (MyHC), as well as a failure to form multinucleated myotubes, which were associated with dramatic increases in MDM2 expression and decrease in Rb protein levels. These results indicate that nutlin-3 can effectively inhibit muscle cell differentiation. - Highlights: • Nutlin-3 inhibits myoblast proliferation and prevents differentiation into myotubes. • Nutlin-3 increases MDM2 expression and down-regulates Rb protein levels. • This study has implication in nutlin-3 treatment of rhabdomyosarcomas.« less

The regulation of Jmjd3 upon the expression of NF-κB downstream inflammatory genes in LPS activated vascular endothelial cells

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

Yu, Shaoqing; Graduate School of Medicine, Nanchang University, Nanchang; Chen, Xia

Inflammatory mediators and adhesion molecules have been implicated in a variety of diseases including atherosclerosis. As both the mediator-releasing and targeted cells, vascular endothelial cells play key role in pathological processes. NF-κB signaling regulates a cluster of inflammatory factors in LPS-activated vascular endothelial cells but the underlying mechanisms remain largely unknown. Here, we investigated the epigenetic regulation of LPS upon the expression of inflammatory mediators and adhesion molecules. We found that LPS treatment promoted jmjd3 expression, enhanced Jmjd3 nuclear accumulation in human vascular endothelial cells. In addition, LPS enhanced the demethylation of H3K27me3, a specific substrate of Jmjd3. LPS treatmentmore » recruited Jmjd3 and NF-κB to the promoter region of target genes, suggesting Jmjd3 synergizes with NF-κB to activate the expression of target genes. We further found that Jmjd3 attenuated the methylation status in promoter region of target genes, culminating in target gene expression. Our findings unveil epigenetic regulations of LPS upon NF-κB pathway and identify Jmjd3 as a critical modulator of NF-κB pathway and potential therapeutic target for NF-κB related diseases including atherosclerosis.« less

Brain endothelial adhesion molecule expression in experimental colitis.

PubMed

Sans, M; Kawachi, S; Soriano, A; Palacín, A; Morise, Z; Granger, D N; Piqué, J M; Grisham, M B; Panés, J

2001-04-01

1) To determine if endothelial expression of adhesion molecules involved in leukocyte recruitment is increased in the brain and other organs in four different models of experimental colitis, and 2) to investigate whether leukocyte infiltration occurs in the brain of colitic animals. Endothelial vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) expression was quantified, using the dual radiolabeled antibody technique in rats with trinitrobenzenesulfonic acid (TNBS)-induced colitis, in mice with dextran sulfate sodium (DSS)-induced colitis, in SCID mice reconstituted with CD45RBhigh T-cells, and in IL-10-/- mice. Leukocyte infiltration in the brain of TNBS-induced colitic rats was assessed by myeloperoxidase activity and immunohistochemical staining with anti-CD45 monoclonal antibody. Marked upregulation of brain endothelial VCAM-1 (2- to 5.5-fold) was consistently found in colitic animals in the four models studied. Brain VCAM-1 strongly correlated with colon VCAM-1 and colon weight. By contrast, upregulation of brain ICAM-1 in colitic animals was only observed in the CD45RBhigh transfer (3-fold) and the TNBS-induced (1.5-fold models). Heart and muscle VCAM-1 and ICAM-1 were not upregulated in colitic animals in the majority of models studied. There was no leukocyte infiltration into the brain of TNBS-induced colitic rats. Our study demonstrates a marked and specific upregulation of endothelial VCAM-1 in the brain of colitic animals. This activation of cerebral endothelial cells was not associated with an infiltration of leukocytes into brain tissue.

Use of mRNA expression signatures to discover small molecule inhibitors of skeletal muscle atrophy

PubMed Central

Adams, Christopher M.; Ebert, Scott M.; Dyle, Michael C.

2017-01-01

Purpose of review Here, we discuss a recently developed experimental strategy for discovering small molecules with potential to prevent and treat skeletal muscle atrophy. Recent findings Muscle atrophy involves and requires widespread changes in skeletal muscle gene expression, which generate complex but measurable patterns of positive and negative changes in skeletal muscle mRNA levels (a.k.a. mRNA expression signatures of muscle atrophy). Many bioactive small molecules generate their own characteristic mRNA expression signatures, and by identifying small molecules whose signatures approximate mirror images of muscle atrophy signatures, one may identify small molecules with potential to prevent and/or reverse muscle atrophy. Unlike a conventional drug discovery approach, this strategy does not rely on a predefined molecular target but rather exploits the complexity of muscle atrophy to identify small molecules that counter the entire spectrum of pathological changes in atrophic muscle. We discuss how this strategy has been used to identify two natural compounds, ursolic acid and tomatidine, that reduce muscle atrophy and improve skeletal muscle function. Summary Discovery strategies based on mRNA expression signatures can elucidate new approaches for preserving and restoring muscle mass and function. PMID:25807353

Use of mRNA expression signatures to discover small molecule inhibitors of skeletal muscle atrophy.

PubMed

Adams, Christopher M; Ebert, Scott M; Dyle, Michael C

2015-05-01

Here, we discuss a recently developed experimental strategy for discovering small molecules with potential to prevent and treat skeletal muscle atrophy. Muscle atrophy involves and requires widespread changes in skeletal muscle gene expression, which generate complex but measurable patterns of positive and negative changes in skeletal muscle mRNA levels (a.k.a. mRNA expression signatures of muscle atrophy). Many bioactive small molecules generate their own characteristic mRNA expression signatures, and by identifying small molecules whose signatures approximate mirror images of muscle atrophy signatures, one may identify small molecules with potential to prevent and/or reverse muscle atrophy. Unlike a conventional drug discovery approach, this strategy does not rely on a predefined molecular target but rather exploits the complexity of muscle atrophy to identify small molecules that counter the entire spectrum of pathological changes in atrophic muscle. We discuss how this strategy has been used to identify two natural compounds, ursolic acid and tomatidine, that reduce muscle atrophy and improve skeletal muscle function. Discovery strategies based on mRNA expression signatures can elucidate new approaches for preserving and restoring muscle mass and function.

Cytokine and adhesion molecule expression evolves between the neutrophilic and lymphocytic phases of viral meningitis.

PubMed

Makis, Alexandros; Shipway, David; Hatzimichael, Eleftheria; Galanakis, Emmanouil; Pshezhetskiy, Dmitry; Chaliasos, Nikolaos; Stebbing, Justin; Siamopoulou, Antigone

2010-09-01

Viral meningitis is characterized by cerebrospinal fluid (CSF) lymphocyte pleocytosis, although neutrophils may predominate in the early phase. The T helper 1 (Th1)/Th2 cytokine balance and expression of adhesion molecules seem to be involved in the CSF chemotaxis. We aimed to determine expression of cytokines and adhesion molecules in enteroviral meningitis. We investigated the serum and CSF levels of adhesion molecules (E-selectin, L-selectin, vascular cell adhesion molecule-1 [VCAM-1], and intracellular adhesion molecule-1 [ICAM-1]) and cytokines (interleukin-12 [IL-12] and IL-4) in 105 children during an outbreak of enteroviral meningitis. Diagnosis was confirmed with positive polymerase chain reaction (PCR) and/or serology for echovirus or Coxsackie virus, and matched with control subjects for clinical features but with negative PCR and/or serology. Apart from VCAM-1, the CSF levels of all investigated inflammatory molecules were significantly increased. In serum, sL-selectin and ICAM-1 levels were significantly higher than control subjects. Serum and CSF L-selectin, serum VCAM-1, and CSF IL-12 were all observed to be expressed in significantly higher levels in the neutrophil-dominant subgroup (72% had duration of symptoms <24 h) than in the lymphocyte-dominant group (87.5% had duration of symptoms >24 h). Serum and CSF ICAM-1 was found at significantly higher levels in the latter group. Evolving expression of adhesion molecules and cytokines indicates a shift from Th1 to Th2 immune responses as infection progresses.

Chronic Restraint Stress Induces an Isoform-Specific Regulation on the Neural Cell Adhesion Molecule in the Hippocampus

PubMed Central

Touyarot, K.; Sandi, C.

2002-01-01

Existing evidence indicates that 21-days exposure of rats to restraint stress induces dendritic atrophy in pyramidal cells of the hippocampus. This phenomenon has been related to altered performance in hippocampal-dependent learning tasks. Prior studies have shown that hippocampal expression of cell adhesion molecules is modified by such stress treatment, with the neural cell adhesion molecule (NCAM) decreasing and L1 increasing, their expression, at both the mRNA and protein levels. Given that NCAM comprises several isoforms, we investigated here whether chronic stress might differentially affect the expression of the three major isoforms (NCAM-120, NCAM-140, NCAM-180) in the hippocampus. In addition, as glucocorticoids have been implicated in the deleterious effects induced by chronic stress, we also evaluated plasma corticosterone levels and the hippocampal expression of the corticosteroid mineralocorticoid receptor (MR) and glucocorticoid receptor (GR). The results showed that the protein concentration of the NCAM-140 isoform decreased in the hippoampus of stressed rats. This effect was isoform-specific, because NCAM-120 and NCAM-180 levels were not significantly modified. In addition, whereas basal levels of plasma corticosterone tended to be increased, MR and GR concentrations were not significantly altered. Although possible changes in NCAM-120, NCAM-180 and corticosteroid receptors at earlier time points of the stress period cannot be ignored; this study suggests that a down-regulation of NCAM-140 might be implicated in the structural alterations consistently shown to be induced in the hippocampus by chronic stress exposure. As NCAM-140 is involved in cell-cell adhesion and neurite outgrowth, these findings suggest that this molecule might be one of the molecular mechanisms involved in the complex interactions among neurodegeneration-related events. PMID:12757368

Expression of checkpoint molecules on myeloid-derived suppressor cells.

PubMed

Ballbach, Marlene; Dannert, Angelika; Singh, Anurag; Siegmund, Darina M; Handgretinger, Rupert; Piali, Luca; Rieber, Nikolaus; Hartl, Dominik

2017-12-01

Myeloid-derived suppressor cells (MDSCs) are a heterogeneous cell population expanded in cancer, infection and autoimmunity capable of suppressing T-cell functions. Checkpoint inhibitors have emerged as a key therapeutic strategy in immune-oncology. While checkpoint molecules were initially associated with T cell functions, recent evidence suggests a broader expression and function in innate myeloid cells. Previous studies provided first evidence for a potential role for checkpoints on MDSCs, yet the human relevance remained poorly understood. Therefore, we investigated the expression and functional relevance of checkpoint molecules in human MDSC-T-cell interactions. Our studies demonstrate that programmed death-ligand 1 (PD-L1) is expressed on granulocytic MDSCs upon co-culture with T cells. Transwell experiments showed that cell-to-cell contact was required for MDSC-T-cell interactions and antibody blocking studies showed that targeting PD-L1 partially impaired MDSC-mediated T-cell suppression. Collectively, these studies suggest a role for PD-L1 in human MDSC function and thereby expand the functionality of this checkpoint beyond T cells, which could pave the way for further understanding and therapeutic targeting of PD-1/PD-L1 in innate immune-mediated diseases. Copyright © 2017 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

Constitutive Expression of Short Hairpin RNA in Vivo Triggers Buildup of Mature Hairpin Molecules

PubMed Central

Ahn, M.; Witting, S.R.; Ruiz, R.; Saxena, R.

2011-01-01

Abstract RNA interference (RNAi) has become the cornerstone technology for studying gene function in mammalian cells. In addition, it is a promising therapeutic treatment for multiple human diseases. Virus-mediated constitutive expression of short hairpin RNA (shRNA) has the potential to provide a permanent source of silencing molecules to tissues, and it is being devised as a strategy for the treatment of liver conditions such as hepatitis B and hepatitis C virus infection. Unintended interaction between silencing molecules and cellular components, leading to toxic effects, has been described in vitro. Despite the enormous interest in using the RNAi technology for in vivo applications, little is known about the safety of constitutively expressing shRNA for multiple weeks. Here we report the effects of in vivo shRNA expression, using helper-dependent adenoviral vectors. We show that gene-specific knockdown is maintained for at least 6 weeks after injection of 1 × 1011 viral particles. Nonetheless, accumulation of mature shRNA molecules was observed up to weeks 3 and 4, and then declined gradually, suggesting the buildup of mature shRNA molecules induced cell death with concomitant loss of viral DNA and shRNA expression. No evidence of well-characterized innate immunity activation (such as interferon production) or saturation of the exportin-5 pathway was observed. Overall, our data suggest constitutive expression of shRNA results in accumulation of mature shRNA molecules, inducing cellular toxicity at late time points, despite the presence of gene silencing. PMID:21780944

Regulation of melanopsin expression.

PubMed

Hannibal, Jens

2006-01-01

Circadian rhythms in mammals are adjusted daily to the environmental day/night cycle by photic input via the retinohypothalamic tract (RHT). Retinal ganglion cells (RGCs) of the RHT constitute a separate light-detecting system in the mammalian retina used for irradiance detection and for transmission to the circadian system and other non-imaging forming processes in the brain. The RGCs of the RHT are intrinsically photosensitive due to the expression of melanopsin, an opsin-like photopigment. This notion is based on anatomical and functional data and on studies of mice lacking melanopsin. Furthermore, heterologous expression of melanopsin in non-neuronal mammalian cell lines was found sufficient to render these cells photosensitive. Even though solid evidence regarding the function of melanopsin exists, little is known about the regulation of melanopsin gene expression. Studies in albino Wistar rats showed that the expression of melanopsin is diurnal at both the mRNA and protein levels. The diurnal changes in melanopsin expression seem, however, to be overridden by prolonged exposure to light or darkness. Significant increase in melanopsin expression was observed from the first day in constant darkness and the expression continued to increase during prolonged exposure in constant darkness. Prolonged exposure to constant light, on the other hand, decreased melanopsin expression to an almost undetectable level after 5 days of constant light. The induction of melanopsin by darkness was even more pronounced if darkness was preceded by light suppression for 5 days. These observations show that dual mechanisms regulate melanopsin gene expression and that the intrinsic light-responsive RGCs in the albino Wistar rat adapt their expression of melanopsin to environmental light and darkness.

Tissue Inhibitor of Metalloproteinase-2 (TIMP-2) expression is regulated by multiple neural differentiation signals

PubMed Central

Jaworski, Diane M.; Pérez-Martínez, Leonor

2010-01-01

Neuronal differentiation requires exquisitely timed cell cycle arrest for progenitors to acquire an appropriate neuronal cell fate and is achieved by communication between soluble signals, such as growth factors and extracellular matrix molecules. Here we report that the expression of TIMP-2, a matrix metalloproteinase inhibitor, is up-regulated by signals that control proliferation (bFGF and EGF) and differentiation (retinoic acid and NGF) in neural progenitor and neuroblastoma cell lines. TIMP-2 expression coincides with the appearance of neurofilament-positive neurons, indicating that TIMP-2 may play a role in neurogenesis. The up-regulation of TIMP-2 expression by proliferative signals suggests a role in the transition from proliferation to neuronal differentiation. Live labeling experiments demonstrate TIMP-2 expression only on α3 integrin-positive cells. Thus, TIMP-2 function may be mediated via interaction with integrin receptor(s). We propose that TIMP-2 represents a component of the neurogenic signaling cascade induced by mitogenic stimuli that may withdraw progenitor cells from the cell cycle permitting their terminal neuronal differentiation. PMID:16805810

The phosphotransferase VanU represses expression of four qrr genes antagonizing VanO-mediated quorum-sensing regulation in Vibrio anguillarum

PubMed Central

Weber, Barbara; Lindell, Kristoffer; El Qaidi, Samir; Hjerde, Erik; Willassen, Nils-Peder

2011-01-01

Vibrio anguillarum utilizes quorum sensing to regulate stress responses required for survival in the aquatic environment. Like other Vibrio species, V. anguillarum contains the gene qrr1, which encodes the ancestral quorum regulatory RNA Qrr1, and phosphorelay quorum-sensing systems that modulate the expression of small regulatory RNAs (sRNAs) that destabilize mRNA encoding the transcriptional regulator VanT. In this study, three additional Qrr sRNAs were identified. All four sRNAs were positively regulated by σ54 and the σ54-dependent response regulator VanO, and showed a redundant activity. The Qrr sRNAs, together with the RNA chaperone Hfq, destabilized vanT mRNA and modulated expression of VanT-regulated genes. Unexpectedly, expression of all four qrr genes peaked at high cell density, and exogenously added N-acylhomoserine lactone molecules induced expression of the qrr genes at low cell density. The phosphotransferase VanU, which phosphorylates and activates VanO, repressed expression of the Qrr sRNAs and stabilized vanT mRNA. A model is presented proposing that VanU acts as a branch point, aiding cross-regulation between two independent phosphorelay systems that activate or repress expression of the Qrr sRNAs, giving flexibility and precision in modulating VanT expression and inducing a quorum-sensing response to stresses found in a constantly changing aquatic environment. PMID:21948044

The phosphotransferase VanU represses expression of four qrr genes antagonizing VanO-mediated quorum-sensing regulation in Vibrio anguillarum.

PubMed

Weber, Barbara; Lindell, Kristoffer; El Qaidi, Samir; Hjerde, Erik; Willassen, Nils-Peder; Milton, Debra L

2011-12-01

Vibrio anguillarum utilizes quorum sensing to regulate stress responses required for survival in the aquatic environment. Like other Vibrio species, V. anguillarum contains the gene qrr1, which encodes the ancestral quorum regulatory RNA Qrr1, and phosphorelay quorum-sensing systems that modulate the expression of small regulatory RNAs (sRNAs) that destabilize mRNA encoding the transcriptional regulator VanT. In this study, three additional Qrr sRNAs were identified. All four sRNAs were positively regulated by σ(54) and the σ(54)-dependent response regulator VanO, and showed a redundant activity. The Qrr sRNAs, together with the RNA chaperone Hfq, destabilized vanT mRNA and modulated expression of VanT-regulated genes. Unexpectedly, expression of all four qrr genes peaked at high cell density, and exogenously added N-acylhomoserine lactone molecules induced expression of the qrr genes at low cell density. The phosphotransferase VanU, which phosphorylates and activates VanO, repressed expression of the Qrr sRNAs and stabilized vanT mRNA. A model is presented proposing that VanU acts as a branch point, aiding cross-regulation between two independent phosphorelay systems that activate or repress expression of the Qrr sRNAs, giving flexibility and precision in modulating VanT expression and inducing a quorum-sensing response to stresses found in a constantly changing aquatic environment.

Glycogen Synthase Kinase 3 (GSK-3) influences epithelial barrier function by regulating Occludin, Claudin-1 and E-cadherin expression

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

Severson, Eric A.; Kwon, Mike; Hilgarth, Roland S.

2010-07-02

The Apical Junctional Complex (AJC) encompassing the tight junction (TJ) and adherens junction (AJ) plays a pivotal role in regulating epithelial barrier function and epithelial cell proliferative processes through signaling events that remain poorly characterized. A potential regulator of AJC protein expression is Glycogen Synthase Kinase-3 (GSK-3). GSK-3 is a constitutively active kinase that is repressed during epithelial-mesenchymal transition (EMT). In the present study, we report that GSK-3 activity regulates the structure and function of the AJC in polarized model intestinal (SK-CO15) and kidney (Madin-Darby Canine Kidney (MDCK)) epithelial cells. Reduction of GSK-3 activity, either by small molecule inhibitors ormore » siRNA targeting GSK-3 alpha and beta mRNA, resulted in increased permeability to both ions and bulk solutes. Immunofluorescence labeling and immunoblot analyses revealed that the barrier defects correlated with decreased protein expression of AJC transmembrane proteins Occludin, Claudin-1 and E-cadherin without influencing other TJ proteins, Zonula Occludens-1 (ZO-1) and Junctional Adhesion Molecule A (JAM-A). The decrease in Occludin and E-cadherin protein expression correlated with downregulation of the corresponding mRNA levels for these respective proteins following GSK-3 inhibition. These observations implicate an important role of GSK-3 in the regulation of the structure and function of the AJC that is mediated by differential modulation of mRNA transcription of key AJC proteins, Occludin, Claudin-1 and E-cadherin.« less

Regulation of drug-metabolizing enzymes in infectious and inflammatory disease: implications for biologics-small molecule drug interactions.

PubMed

Mallick, Pankajini; Taneja, Guncha; Moorthy, Bhagavatula; Ghose, Romi

2017-06-01

Drug-metabolizing enzymes (DMEs) are primarily down-regulated during infectious and inflammatory diseases, leading to disruption in the metabolism of small molecule drugs (smds), which are increasingly being prescribed therapeutically in combination with biologics for a number of chronic diseases. The biologics may exert pro- or anti-inflammatory effect, which may in turn affect the expression/activity of DMEs. Thus, patients with infectious/inflammatory diseases undergoing biologic/smd treatment can have complex changes in DMEs due to combined effects of the disease and treatment. Areas covered: We will discuss clinical biologics-SMD interaction and regulation of DMEs during infection and inflammatory diseases. Mechanistic studies will be discussed and consequences on biologic-small molecule combination therapy on disease outcome due to changes in drug metabolism will be highlighted. Expert opinion: The involvement of immunomodulatory mediators in biologic-SMDs is well known. Regulatory guidelines recommend appropriate in vitro or in vivo assessments for possible interactions. The role of cytokines in biologic-SMDs has been documented. However, the mechanisms of drug-drug interactions is much more complex, and is probably multi-factorial. Studies aimed at understanding the mechanism by which biologics effect the DMEs during inflammation/infection are clinically important.

Dynamic pattern of endothelial cell adhesion molecule expression in muscle and perineural vessels from patients with classic polyarteritis nodosa.

PubMed

Coll-Vinent, B; Cebrián, M; Cid, M C; Font, C; Esparza, J; Juan, M; Yagüe, J; Urbano-Márquez, A; Grau, J M

1998-03-01

To investigate endothelial cell adhesion molecule expression in vessels from patients with classic polyarteritis nodosa (PAN). Frozen sections of 21 muscle and 16 nerve samples from 30 patients with biopsy-proven PAN and 12 histologically normal muscle and 2 histologically normal nerve samples from 12 controls were studied immunohistochemically, using specific monoclonal antibodies (MAb) that recognize adhesion molecules. Adhesion molecules identified were intercellular adhesion molecule 1 (ICAM-1), ICAM-2, ICAM-3, vascular cell adhesion molecule 1 (VCAM-1), platelet endothelial cell adhesion molecule 1 (PECAM-1), E-selectin, P-selectin, L-selectin, lymphocyte function-associated antigen 1 (LFA-1), and very late activation antigen 4 (VLA-4). Neutrophils were identified with a MAb recognizing neutrophil elastase. Endothelial cells were identified with the lectin ulex europaeus. In early lesions, expression of PECAM-1, ICAM-1, ICAM-2, and P-selectin was similar to that in control samples, and VCAM-1 and E-selectin were induced in vascular endothelium. In advanced lesions, immunostaining for adhesion molecules diminished or disappeared in luminal endothelium, whereas these molecules were clearly expressed in microvessels within and surrounding inflamed vessels. Staining in endothelia from vessels in a healing stage tended to be negative. A high proportion of infiltrating leukocytes expressed LFA-1 and VLA-4, and only a minority expressed L-selectin. No relationship between the expression pattern of adhesion molecules and clinical features, disease duration, or previous corticosteroid treatment was observed. Endothelial adhesion molecule expression in PAN is a dynamic process that varies according to the histopathologic stage of the vascular lesions. The preferential expression of constitutive and inducible adhesion molecules in microvessels suggests that angiogenesis contributes to the persistence of inflammatory infiltration in PAN.

Mechanical strain stimulates vasculogenesis and expression of angiogenesis guidance molecules of embryonic stem cells through elevation of intracellular calcium, reactive oxygen species and nitric oxide generation.

PubMed

Sharifpanah, Fatemeh; Behr, Sascha; Wartenberg, Maria; Sauer, Heinrich

2016-12-01

Differentiation of embryonic stem (ES) cells may be regulated by mechanical strain. Herein, signaling molecules underlying mechanical stimulation of vasculogenesis and expression of angiogenesis guidance cues were investigated in ES cell-derived embryoid bodies. Treatment of embryoid bodies with 10% static mechanical strain using a Flexercell strain system significantly increased CD31-positive vascular structures and the angiogenesis guidance molecules plexinB1, ephrin B2, neuropilin1 (NRP1), semaphorin 4D (sem4D) and robo4 as well as vascular endothelial growth factor (VEGF), fibroblast growth factor-2 (FGF-2) and platelet-derived growth factor-BB (PDGF-BB) as evaluated by Western blot and real time RT-PCR. In contrast ephrin type 4 receptor B (EphB4) expression was down-regulated upon mechanical strain, indicating an arterial-type differentiation. Robo1 protein expression was modestly increased with no change in mRNA expression. Mechanical strain increased intracellular calcium as well as reactive oxygen species (ROS) and nitric oxide (NO). Mechanical strain-induced vasculogenesis was abolished by the NOS inhibitor L-NAME, the NADPH oxidase inhibitor VAS2870, upon chelation of intracellular calcium by BAPTA as well as upon siRNA inactivation of ephrin B2, NRP1 and robo4. BAPTA blunted the strain-induced expression of angiogenic growth factors, the increase in NO and ROS as well as the expression of NRP1, sem4D and plexinB1, whereas ephrin B2, EphB4 as well as robo1 and robo4 expression were not impaired. Mechanical strain stimulates vasculogenesis of ES cells by the intracellular messengers ROS, NO and calcium as well as by upregulation of angiogenesis guidance molecules and the angiogenic growth factors VEGF, FGF-2 and PDGF-BB. Copyright © 2016 Elsevier B.V. All rights reserved.

Pharmacological modulation of endothelial cell-associated adhesion molecule expression: implications for future treatment of dermatological diseases.

PubMed

Foster, C A; Dreyfuss, M; Mandak, B; Meingassner, J G; Naegeli, H U; Nussbaumer, A; Oberer, L; Scheel, G; Swoboda, E M

1994-11-01

Skin diseases with an inflammatory component, regardless of their etiology, are characterized at some point by the extravasation and subsequent infiltration of leukocytes into the dermal and/or epidermal compartments. This trafficking pattern is determined by a complex series of events whereby the leukocytes interact with cell adhesion molecules (CAM), particularly those induced on endothelial cells following activation with various inflammatory mediators. Vascular CAMs belonging to the selectin family (i.e., P-selectin and E-selectin) are thought to mediate early and reversible events involving leukocyte rolling and margination along the lumenal surface of microvascular cells (post-capillary venules). Certain members of the immunoglobulin supergene family (i.e., VCAM-1 and ICAM-1) regulate later and irreversible steps which lead to firm attachment and subsequent diapedesis of leukocytes. Accumulating evidence suggests that if one blocks the ligand-binding sites between leukocytes and endothelial cells, or inhibits vascular CAM expression, hematopoietic cell extravasation and progressive inflammatory events can be greatly diminished. To identify such inhibitors we developed a cell-based Elisa using the human microvascular cell line HMEC-1. As reported in the present paper, this approach yielded a naturally-occurring, low molecular weight compound which potently inhibits cytokine-induced adhesion molecule expression on cultured endothelial cells, without modulating "house-keeping" proteins.

Impact of exogenous lipase supplementation on growth, intestinal function, mucosal immune and physical barrier, and related signaling molecules mRNA expression of young grass carp (Ctenopharyngodon idella).

PubMed

Liu, Sen; Feng, Lin; Jiang, Wei-Dan; Liu, Yang; Jiang, Jun; Wu, Pei; Zeng, Yun-Yun; Xu, Shu-De; Kuang, Sheng-Yao; Tang, Ling; Tang, Wu-Neng; Zhang, Yong-An; Zhou, Xiao-Qiu

2016-08-01

This study investigated the effects of exogenous lipase supplementation on the growth performance, intestinal growth and function, immune response and physical barrier function, and related signaling molecules mRNA expression of young grass carp (Ctenopharyngodon idella). A total of 450 grass carp (255.02 ± 0.34 g) were fed five diets for 60 days. There were 5 dietary treatments that included a normal protein and lipid diet containing 30% crude protein (CP) with 5% ether extract (EE), and the low-protein and high-lipid diets (28% CP, 6% EE) supplemented with graded levels of exogenous lipase supplementation activity at 0, 1193, 2560 and 3730 U/kg diet. The results indicated that compared with a normal protein and lipid diet (30% CP, 5% EE), a low-protein and high-lipid diet (28% CP, 6% EE) (un-supplemented lipase) improved lysozyme activities and complement component 3 contents in the distal intestine (DI), interleukin 10 mRNA expression in the proximal intestine (PI), and glutathione S-transferases activity and glutathione content in the intestine of young grass carp. In addition, in low-protein and high-lipid diets, optimal exogenous lipase supplementation significantly increased acid phosphatase (ACP) activities and complement component 3 (C3) contents (P < 0.05), up-regulated the relative mRNA levels of antimicrobial peptides (liver expressed antimicrobial peptide 2 and hepcidin) and anti-inflammatory cytokines (interleukin 10 and transforming growth factor β1) and signaling molecules inhibitor protein-κBα (IκBα) and target of rapamycin (TOR) (P < 0.05), down-regulated the mRNA levels of pro-inflammatory cytokines (tumor necrosis factor α, interleukin 8, interferon γ2, and interleukin 1β), and signaling molecules (nuclear factor kappa B p65, IκB kinase β, IκB kinase γ) (P < 0.05) in the intestine of young grass carp. Moreover, optimal exogenous lipase supplementation significantly decreased reactive oxygen species (ROS), malondialdehyde

EGR-1 regulates Ho-1 expression induced by cigarette smoke

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

Chen, Huaqun, E-mail: chenhuaqun@njnu.edu.cn; Wang, Lijuan; Gong, Tao

2010-05-28

As an anti-oxidant molecule, heme oxygenase-1 (HO-1) has been implicated in the protection of lung injury by cigarette smoke (CS). The mechanisms regulating its expression have not been defined. In this report, the role of early growth response 1 (EGR-1) in the regulation of Ho-1 expression was investigated. In C57BL/6 mice with CS exposure, HO-1 was greatly increased in bronchial epithelial cells and alveolar inflammatory cells. In primary cultured mouse lung fibroblasts and RAW264.7 cells exposed to cigarette smoke water extract (CSE), an increase in HO-1 protein level was detected. In addition, CSE induced HO-1 expression was decreased in Egr-1more » deficient mouse embryo fibroblasts (Egr-1{sup -/-} MEFs). Nuclear localization of EGR-1 was examined in mouse lung fibroblasts after exposure to CSE. Luciferase reporter activity assays showed that the enhancer region of the Ho-1 gene containing a proposed EGR-1 binding site was responsible for the induction of HO-1. A higher increase of alveolar mean linear intercept (Lm) was observed in lung tissues, and a larger increase in the number of total cells and monocytes/macrophages from bronchial alveolar lavage fluid was found in CS-exposed mice by loss of function of EGR-1 treatment. In summary, the present data demonstrate that EGR-1 plays a critical role in HO-1 production induced by CS.« less

Glucocorticoid Signaling Enhances Expression of Glucose-Sensing Molecules in Immature Pancreatic Beta-Like Cells Derived from Murine Embryonic Stem Cells In Vitro.

PubMed

Ghazalli, Nadiah; Wu, Xiaoxing; Walker, Stephanie; Trieu, Nancy; Hsin, Li-Yu; Choe, Justin; Chen, Chialin; Hsu, Jasper; LeBon, Jeanne; Kozlowski, Mark T; Rawson, Jeffrey; Tirrell, David A; Yip, M L Richard; Ku, Hsun Teresa

2018-06-06

Pluripotent stem cells may serve as an alternative source of beta-like cells for replacement therapy of type 1 diabetes; however, the beta-like cells generated in many differentiation protocols are immature. The maturation of endogenous beta cells involves an increase in insulin expression starting in late gestation and a gradual acquisition of the abilities to sense glucose and secrete insulin by week 2 after birth in mice; however, what molecules regulate these maturation processes are incompletely known. In this study, we aim to identify small molecules that affect immature beta cells. A cell-based assay, using pancreatic beta-like cells derived from murine embryonic stem (ES) cells harboring a transgene containing an insulin 1-promoter driven enhanced green fluorescent protein reporter, was used to screen a compound library (NIH Clinical Collection-003). Cortisone, a glucocorticoid, was among five positive hit compounds. Quantitative reverse transcription-polymerase chain reaction analysis revealed that glucocorticoids enhance the gene expression of not only insulin 1 but also glucose transporter-2 (Glut2; Slc2a2) and glucokinase (Gck), two molecules important for glucose sensing. Mifepristone, a pharmacological inhibitor of glucocorticoid receptor (GR) signaling, reduced the effects of glucocorticoids on Glut2 and Gck expression. The effects of glucocorticoids on ES-derived cells were further validated in immature primary islets. Isolated islets from 1-week-old mice had an increased Glut2 and Gck expression in response to a 4-day treatment of exogenous hydrocortisone in vitro. Gene deletion of GR in beta cells using rat insulin 2 promoter-driven Cre crossed with GR flox/flox mice resulted in a reduced gene expression of Glut2, but not Gck, and an abrogation of insulin secretion when islets were incubated in 0.5 mM d-glucose and stimulated by 17 mM d-glucose in vitro. These results demonstrate that glucocorticoids positively regulate glucose sensors in

DMH1, a Highly Selective Small Molecule BMP Inhibitor Promotes Neurogenesis of hiPSCs: Comparison of PAX6 and SOX1 Expression during Neural Induction

PubMed Central

2012-01-01

Recent successes in deriving human-induced pluripotent stem cells (hiPSCs) allow for the possibility of studying human neurons derived from patients with neurological diseases. Concomitant inhibition of the BMP and TGF-β1 branches of the TGF-β signaling pathways by the endogenous antagonist, Noggin, and the small molecule SB431542, respectively, induces efficient neuralization of hiPSCs, a method known as dual-SMAD inhibition. The use of small molecule inhibitors instead of their endogenous counterparts has several advantages including lower cost, consistent activity, and the maintenance of xeno-free culture conditions. We tested the efficacy of DMH1, a highly selective small molecule BMP-inhibitor for its potential to replace Noggin in the neuralization of hiPSCs. We compare Noggin and DMH1-induced neuralization of hiPSCs by measuring protein and mRNA levels of pluripotency and neural precursor markers over a period of seven days. The regulation of five of the six markers assessed was indistinguishable in the presence of concentrations of Noggin or DMH1 that have been shown to effectively inhibit BMP signaling in other systems. We observed that by varying the DMH1 or Noggin concentration, we could selectively modulate the number of SOX1 expressing cells, whereas PAX6, another neural precursor marker, remained the same. The level and timing of SOX1 expression have been shown to affect neural induction as well as neural lineage. Our observations, therefore, suggest that BMP-inhibitor concentrations need to be carefully monitored to ensure appropriate expression levels of all transcription factors necessary for the induction of a particular neuronal lineage. We further demonstrate that DMH1-induced neural progenitors can be differentiated into β3-tubulin expressing neurons, a subset of which also express tyrosine hydroxylase. Thus, the combined use of DMH1, a highly specific BMP-pathway inhibitor, and SB431542, a TGF-β1-pathway specific inhibitor, provides us

c-di-AMP: An Essential Molecule in the Signaling Pathways that Regulate the Viability and Virulence of Gram-Positive Bacteria

PubMed Central

Fahmi, Tazin; Port, Gary C.

2017-01-01

Signal transduction pathways enable organisms to monitor their external environment and adjust gene regulation to appropriately modify their cellular processes. Second messenger nucleotides including cyclic adenosine monophosphate (c-AMP), cyclic guanosine monophosphate (c-GMP), cyclic di-guanosine monophosphate (c-di-GMP), and cyclic di-adenosine monophosphate (c-di-AMP) play key roles in many signal transduction pathways used by prokaryotes and/or eukaryotes. Among the various second messenger nucleotides molecules, c-di-AMP was discovered recently and has since been shown to be involved in cell growth, survival, and regulation of virulence, primarily within Gram-positive bacteria. The cellular level of c-di-AMP is maintained by a family of c-di-AMP synthesizing enzymes, diadenylate cyclases (DACs), and degradation enzymes, phosphodiesterases (PDEs). Genetic manipulation of DACs and PDEs have demonstrated that alteration of c-di-AMP levels impacts both growth and virulence of microorganisms. Unlike other second messenger molecules, c-di-AMP is essential for growth in several bacterial species as many basic cellular functions are regulated by c-di-AMP including cell wall maintenance, potassium ion homeostasis, DNA damage repair, etc. c-di-AMP follows a typical second messenger signaling pathway, beginning with binding to receptor molecules to subsequent regulation of downstream cellular processes. While c-di-AMP binds to specific proteins that regulate pathways in bacterial cells, c-di-AMP also binds to regulatory RNA molecules that control potassium ion channel expression in Bacillus subtilis. c-di-AMP signaling also occurs in eukaryotes, as bacterially produced c-di-AMP stimulates host immune responses during infection through binding of innate immune surveillance proteins. Due to its existence in diverse microorganisms, its involvement in crucial cellular activities, and its stimulating activity in host immune responses, c-di-AMP signaling pathway has become an

Aberrant Expression of Retinoic Acid Signaling Molecules Influences Patient Survival in Astrocytic Gliomas

PubMed Central

Campos, Benito; Centner, Franz-Simon; Bermejo, Justo Lorenzo; Ali, Ramadan; Dorsch, Katharina; Wan, Feng; Felsberg, Jörg; Ahmadi, Rezvan; Grabe, Niels; Reifenberger, Guido; Unterberg, Andreas; Burhenne, Jürgen; Herold-Mende, Christel

2011-01-01

Undifferentiated cell populations may influence tumor growth in malignant glioma. We investigated potential disruptions in the retinoic acid (RA) differentiation pathway that could lead to a loss of differentiation capacity, influencing patient prognosis. Expression of key molecules belonging to the RA differentiation pathway was analyzed in 283 astrocytic gliomas and was correlated with tumor proliferation, tumor differentiation, and patient survival. In addition, in situ concentrations of retinoids were measured in tumors, and RA signaling events were studied in vitro. Unlike other tumors, in gliomas expression of most RA signaling molecules increased with malignancy and was associated with augmented intratumoral retinoid levels in high-grade gliomas. Aberrantly expressed RA signaling molecules included i) the retinol-binding protein CRBP1, which facilitates cellular retinoid uptake; ii) ALDH1A1, capable of activating RA precursors; iii) the RA-degrading enzyme CYP26B1; and iv) the RA-binding protein FABP5, which can inhibit RA-induced differentiation. In contrast, expression of the RA-binding protein CRABP2, which fosters differentiation, was decreased in high-grade tumors. Moreover, expression of CRBP1 correlated with tumor proliferation, and FABP5 expression correlated with an undifferentiated tumor phenotype. CRBP1 and ALDH1A1 were independent prognostic markers for adverse patient survival. Our data indicate a complex and clinically relevant deregulation of RA signaling, which seems to be a central event in glioma pathogenesis. PMID:21514413

Expression levels of MHC class I molecules are inversely correlated with promiscuity of peptide binding

PubMed Central

Chappell, Paul E; Meziane, El Kahina; Harrison, Michael; Magiera, Łukasz; Hermann, Clemens; Mears, Laura; Wrobel, Antoni G; Durant, Charlotte; Nielsen, Lise Lotte; Buus, Søren; Ternette, Nicola; Mwangi, William; Butter, Colin; Nair, Venugopal; Ahyee, Trudy; Duggleby, Richard; Madrigal, Alejandro; Roversi, Pietro; Lea, Susan M; Kaufman, Jim

2015-01-01

Highly polymorphic major histocompatibility complex (MHC) molecules are at the heart of adaptive immune responses, playing crucial roles in many kinds of disease and in vaccination. We report that breadth of peptide presentation and level of cell surface expression of class I molecules are inversely correlated in both chickens and humans. This relationship correlates with protective responses against infectious pathogens including Marek's disease virus leading to lethal tumours in chickens and human immunodeficiency virus infection progressing to AIDS in humans. We propose that differences in peptide binding repertoire define two groups of MHC class I molecules strategically evolved as generalists and specialists for different modes of pathogen resistance. We suggest that differences in cell surface expression level ensure the development of optimal peripheral T cell responses. The inverse relationship of peptide repertoire and expression is evidently a fundamental property of MHC molecules, with ramifications extending beyond immunology and medicine to evolutionary biology and conservation. DOI: http://dx.doi.org/10.7554/eLife.05345.001 PMID:25860507

Expression of major histocompatibility complex class II and costimulatory molecules in oral carcinomas in vitro.

PubMed

Villarroel-Dorrego, Mariana; Speight, Paul M; Barrett, A William

2005-01-01

Recognition in the 1980 s that keratinocytes can express class II molecules of the Major Histocompatibility Complex (MHC) first raised the possibility that these cells might have an immunological function, and may even act as antigen presenting cells (APC). For effective T lymphocyte activation, APC require, in addition to MHC II, appropriate costimulatory signals. The aim of this study was to determine the expression of MHC class II and the co-stimulatory molecules CD40, CD80 and CD86 in keratinocytes derived from healthy oral mucosa and oral carcinomas. Using flow cytometry, it was confirmed that oral keratinocytes, switch on, expression of MHC class II molecules after stimulation with IFNgamma in vitro. All keratinocyte lines expressed CD40 constitutively; by contrast, CD80 and CD86 were universally absent. Loss of CD80 and CD86 may be one means whereby tumours escape immunological surveillance.

Structural basis of AMPK regulation by small molecule activators

NASA Astrophysics Data System (ADS)

Xiao, Bing; Sanders, Matthew J.; Carmena, David; Bright, Nicola J.; Haire, Lesley F.; Underwood, Elizabeth; Patel, Bhakti R.; Heath, Richard B.; Walker, Philip A.; Hallen, Stefan; Giordanetto, Fabrizio; Martin, Stephen R.; Carling, David; Gamblin, Steven J.

2013-12-01

AMP-activated protein kinase (AMPK) plays a major role in regulating cellular energy balance by sensing and responding to increases in AMP/ADP concentration relative to ATP. Binding of AMP causes allosteric activation of the enzyme and binding of either AMP or ADP promotes and maintains the phosphorylation of threonine 172 within the activation loop of the kinase. AMPK has attracted widespread interest as a potential therapeutic target for metabolic diseases including type 2 diabetes and, more recently, cancer. A number of direct AMPK activators have been reported as having beneficial effects in treating metabolic diseases, but there has been no structural basis for activator binding to AMPK. Here we present the crystal structure of human AMPK in complex with a small molecule activator that binds at a site between the kinase domain and the carbohydrate-binding module, stabilising the interaction between these two components. The nature of the activator-binding pocket suggests the involvement of an additional, as yet unidentified, metabolite in the physiological regulation of AMPK. Importantly, the structure offers new opportunities for the design of small molecule activators of AMPK for treatment of metabolic disorders.

BMP regulates regional gene expression in the dorsal otocyst through canonical and non-canonical intracellular pathways

PubMed Central

2016-01-01

The inner ear consists of two otocyst-derived, structurally and functionally distinct components: the dorsal vestibular and ventral auditory compartments. BMP signaling is required to form the vestibular compartment, but how it complements other required signaling molecules and acts intracellularly is unknown. Using spatially and temporally controlled delivery of signaling pathway regulators to developing chick otocysts, we show that BMP signaling regulates the expression of Dlx5 and Hmx3, both of which encode transcription factors essential for vestibular formation. However, although BMP regulates Dlx5 through the canonical SMAD pathway, surprisingly, it regulates Hmx3 through a non-canonical pathway involving both an increase in cAMP-dependent protein kinase A activity and the GLI3R to GLI3A ratio. Thus, both canonical and non-canonical BMP signaling establish the precise spatiotemporal expression of Dlx5 and Hmx3 during dorsal vestibular development. The identification of the non-canonical pathway suggests an intersection point between BMP and SHH signaling, which is required for ventral auditory development. PMID:27151948

Expression of the oxygen-regulated protein ORP150 accelerates wound healing by modulating intracellular VEGF transport

PubMed Central

Ozawa, Kentaro; Kondo, Toshikazu; Hori, Osamu; Kitao, Yasuko; Stern, David M.; Eisenmenger, Wolfgang; Ogawa, Satoshi; Ohshima, Tohru

2001-01-01

Expression of angiogenic factors such as VEGF under conditions of hypoxia or other kinds of cell stress contributes to neovascularization during wound healing. The inducible endoplasmic reticulum chaperone oxygen-regulated protein 150 (ORP150) is expressed in human wounds along with VEGF. Colocalization of these two molecules was observed in macrophages in the neovasculature, suggesting a role of ORP150 in the promotion of angiogenesis. Local administration of ORP150 sense adenovirus to wounds of diabetic mice, a treatment that efficiently targeted this gene product to the macrophages of wound beds, increased VEGF antigen in wounds and accelerated repair and neovascularization. In cultured human macrophages, inhibition of ORP150 expression caused retention of VEGF antigen within the endoplasmic reticulum (ER), while overexpression of ORP150 promoted the secretion of VEGF into hypoxic culture supernatants. Taken together, these data suggest an important role for ORP150 in the setting of impaired wound repair and identify a key, inducible chaperone-like molecule in the ER. This novel facet of the angiogenic response may be amenable to therapeutic manipulation. PMID:11435456

Cryptotanshinone inhibits oxidized LDL-induced adhesion molecule expression via ROS dependent NF-κB pathways

PubMed Central

Zhao, Wenwen; Wu, Chuanhong; Chen, Xiuping

2016-01-01

ABSTRACT Adhesion molecules, such as intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin, play important roles in the initial stage of atherosclerosis. Cryptotanshinone (CPT), a natural compound isolated from Salvia miltiorrhiza Bunge, exhibits anti-atherosclerotic activity although the underlying mechanisms remain elusive. In this study, the protective effect of CPT against oxidized low-density lipoprotein (ox-LDL)-induced adhesion molecule expression was investigated in human umbilical vein endothelial cells. Ox-LDL significantly induced ICAM-1, VCAM-1, and E-selectin expression at the mRNA and protein levels but reduced eNOS phosphorylation and NO generation, which were reversed by CPT pretreatment. Sodium nitroprusside, a NO donor, N-acetyl-L-cysteine (NAC), a reactive oxygen species (ROS) scavenger, and BAY117082, a NF-κB inhibitor, inhibited ox-LDL-induced ICAM-1, VCAM-1, and E-selectin expression. Ox-LDL-induced ROS production was significantly inhibited by CPT and NAC. Furthermore, ox-LDL activated the NF-κB signaling pathway by inducing phosphorylation of IKKβ and IκBα, promoting the interaction of IKKβ and IκBα, and increasing p65 nuclear translocation, which were significantly inhibited by CPT. In addition, CPT, NAC, and BAY117082 inhibited ox-LDL-induced membrane expression of ICAM-1, VCAM-1, E-selectin, and endothelial–monocyte adhesion and restored eNOS phosphorylation and NO generation. Results suggested that CPT inhibited ox-LDL-induced adhesion molecule expression by decreasing ROS and inhibiting the NF-κB pathways, which provides new insight into the anti-atherosclerotic mechanism of CPT. PMID:26647279

Chlorella 11-Peptide Inhibits the Production of Macrophage-Induced Adhesion Molecules and Reduces Endothelin-1 Expression and Endothelial Permeability

PubMed Central

Shih, Mei Fen; Chen, Lih Chi; Cherng, Jong Yuh

2013-01-01

The inflammation process in large vessels involves the up-regulation of vascular adhesion molecules such as endothelial cell selectin (E-selectin), intercellular cell adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) which are also known as the markers of atherosclerosis. We have reported that Chlorella 11-peptide exhibited effective anti-inflammatory effects. This peptide with an amino sequence Val-Glu-Cys-Tyr-Gly-Pro-Asn-Arg-Pro-Gln-Phe was further examined for its potential in preventing atherosclerosis in this study. In particular, the roles of Chlorella 11-peptide in lowering the production of vascular adhesion molecules, monocyte chemoattractant protein (MCP-1) and expression of endothelin-1 (ET-1) from endothelia (SVEC4-10 cells) were studied. The production of E-selectin, ICAM-1, VCAM-1 and MCP-1 in SVEC4-10 cells was measured with ELISA. The mRNA expression of ET-1 was analyzed by RT-PCR and agarose gel. Results showed that Chlorella 11-peptide significantly suppressed the levels of E-selectin, ICAM, VCAM, MCP-1 as well as ET-1 gene expression. The inhibition of ICAM-1 and VCAM-1 production by Chlorella 11-peptide was reversed in the presence of protein kinase A inhibitor (H89) which suggests that the cAMP pathway was involved in the inhibitory cause of the peptide. In addition, this peptide was shown to reduce the extent of increased intercellular permeability induced by combination of 50% of lipopolysaccharide (LPS)-activated RAW 264.7 cells medium and 50% normal SEVC cell culture medium (referred to as 50% RAW-conditioned medium). These data demonstrate that Chlorella 11-peptide is a promising biomolecule in preventing chronic inflammatory-related vascular diseases. PMID:24129228

Iron regulates expression of Bacillus cereus hemolysin II via global regulator Fur.

PubMed

Sineva, Elena; Shadrin, Andrey; Rodikova, Ekaterina A; Andreeva-Kovalevskaya, Zhanna I; Protsenko, Alexey S; Mayorov, Sergey G; Galaktionova, Darya Yu; Magelky, Erica; Solonin, Alexander S

2012-07-01

The capacity of pathogens to respond to environmental signals, such as iron concentration, is key to bacterial survival and establishment of a successful infection. Bacillus cereus is a widely distributed bacterium with distinct pathogenic properties. Hemolysin II (HlyII) is one of its pore-forming cytotoxins and has been shown to be involved in bacterial pathogenicity in a number of cell and animal models. Unlike many other B. cereus pathogenicity factors, HlyII is not regulated by pleiotropic transcriptional regulator PlcR but is controlled by its own regulator, HlyIIR. Using a combination of in vivo and in vitro techniques, we show that hlyII expression is also negatively regulated by iron by the global regulator Fur via direct interaction with the hlyII promoter. DNase I footprinting and in vitro transcription experiments indicate that Fur prevents RNA polymerase binding to the hlyII promoter. HlyII expression profiles demonstrate that both HlyIIR and Fur regulate HlyII expression in a concerted fashion, with the effect of Fur being maximal in the early stages of bacterial growth. In sum, these results show that Fur serves as a transcriptional repressor for hlyII expression.

Mesencephalic dopaminergic neurons express a repertoire of olfactory receptors and respond to odorant-like molecules.

PubMed

Grison, Alice; Zucchelli, Silvia; Urzì, Alice; Zamparo, Ilaria; Lazarevic, Dejan; Pascarella, Giovanni; Roncaglia, Paola; Giorgetti, Alejandro; Garcia-Esparcia, Paula; Vlachouli, Christina; Simone, Roberto; Persichetti, Francesca; Forrest, Alistair R R; Hayashizaki, Yoshihide; Carloni, Paolo; Ferrer, Isidro; Lodovichi, Claudia; Plessy, Charles; Carninci, Piero; Gustincich, Stefano

2014-08-27

The mesencephalic dopaminergic (mDA) cell system is composed of two major groups of projecting cells in the Substantia Nigra (SN) (A9 neurons) and the Ventral Tegmental Area (VTA) (A10 cells). Selective degeneration of A9 neurons occurs in Parkinson's disease (PD) while abnormal function of A10 cells has been linked to schizophrenia, attention deficit and addiction. The molecular basis that underlies selective vulnerability of A9 and A10 neurons is presently unknown. By taking advantage of transgenic labeling, laser capture microdissection coupled to nano Cap-Analysis of Gene Expression (nanoCAGE) technology on isolated A9 and A10 cells, we found that a subset of Olfactory Receptors (OR)s is expressed in mDA neurons. Gene expression analysis was integrated with the FANTOM5 Helicos CAGE sequencing datasets, showing the presence of these ORs in selected tissues and brain areas outside of the olfactory epithelium. OR expression in the mesencephalon was validated by RT-PCR and in situ hybridization. By screening 16 potential ligands on 5 mDA ORs recombinantly expressed in an heterologous in vitro system, we identified carvone enantiomers as agonists at Olfr287 and able to evoke an intracellular Ca2+ increase in solitary mDA neurons. ORs were found expressed in human SN and down-regulated in PD post mortem brains. Our study indicates that mDA neurons express ORs and respond to odor-like molecules providing new opportunities for pharmacological intervention in disease.

EphA2 Expression Regulates Inflammation and Fibroproliferative Remodeling in Atherosclerosis.

PubMed

Finney, Alexandra C; Funk, Steven D; Green, Jonette M; Yurdagul, Arif; Rana, Mohammad Atif; Pistorius, Rebecca; Henry, Miriam; Yurochko, Andrew; Pattillo, Christopher B; Traylor, James G; Chen, Jin; Woolard, Matthew D; Kevil, Christopher G; Orr, A Wayne

2017-08-08

Atherosclerotic plaque formation results from chronic inflammation and fibroproliferative remodeling in the vascular wall. We previously demonstrated that both human and mouse atherosclerotic plaques show elevated expression of EphA2, a guidance molecule involved in cell-cell interactions and tumorigenesis. Here, we assessed the role of EphA2 in atherosclerosis by deleting EphA2 in a mouse model of atherosclerosis (Apoe - /- ) and by assessing EphA2 function in multiple vascular cell culture models. After 8 to 16 weeks on a Western diet, male and female mice were assessed for atherosclerotic burden in the large vessels, and plasma lipid levels were analyzed. Despite enhanced weight gain and plasma lipid levels compared with Apoe -/- controls, EphA2 -/- Apoe -/- knockout mice show diminished atherosclerotic plaque formation, characterized by reduced proinflammatory gene expression and plaque macrophage content. Although plaque macrophages express EphA2, EphA2 deletion does not affect macrophage phenotype, inflammatory responses, and lipid uptake, and bone marrow chimeras suggest that hematopoietic EphA2 deletion does not affect plaque formation. In contrast, endothelial EphA2 knockdown significantly reduces monocyte firm adhesion under flow. In addition, EphA2 -/- Apoe -/- mice show reduced progression to advanced atherosclerotic plaques with diminished smooth muscle and collagen content. Consistent with this phenotype, EphA2 shows enhanced expression after smooth muscle transition to a synthetic phenotype, and EphA2 depletion reduces smooth muscle proliferation, mitogenic signaling, and extracellular matrix deposition both in atherosclerotic plaques and in vascular smooth muscle cells in culture. Together, these data identify a novel role for EphA2 in atherosclerosis, regulating both plaque inflammation and progression to advanced atherosclerotic lesions. Cell culture studies suggest that endothelial EphA2 contributes to atherosclerotic inflammation by promoting

c-Fos downregulation positively regulates EphA5 expression in a congenital hypothyroidism rat model.

PubMed

Song, Honghua; Zheng, Yuqin; Cai, Fuying; Ma, Yanyan; Yang, Jingyue; Wu, Youjia

2018-04-01

The EphA5 receptor is well established as an axon guidance molecule during neural system development and plays an important role in dendritic spine formation and synaptogenesis. Our previous study has showed that EphA5 is decreased in the developing brain of congenital hypothyroidism (CH) and the EphA5 promoter methylation modification participates in its decrease. c-Fos, a well-kown transcription factor, has been considered in association with brain development. Bioinformatics analysis showed that the EphA5 promoter region contained five putative c-fos binding sites. The chromatin immunoprecipitation (ChIP) assays were used to assess the direct binding of c-fos to the EphA5 promoter. Furthermore, dual-luciferase assays showed that these three c-fos protein binding sites were positive regulatory elements for EphA5 expression in PC12 cells. Moreover, We verified c-fos positively regulation for EphA5 expression in CH model. Q-PCR and Western blot showed that c-fos overexpression could upregulate EphA5 expression in hippocampal neurons of rats with CH. Our results suggest that c-fos positively regulates EphA5 expression in CH rat model.

Genome-Scale Architecture of Small Molecule Regulatory Networks and the Fundamental Trade-Off between Regulation and Enzymatic Activity

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

Reznik, Ed; Christodoulou, Dimitris; Goldford, Joshua E.

Metabolic flux is in part regulated by endogenous small molecules that modulate the catalytic activity of an enzyme, e.g., allosteric inhibition. In contrast to transcriptional regulation of enzymes, technical limitations have hindered the production of a genome-scale atlas of small molecule-enzyme regulatory interactions. Here, we develop a framework leveraging the vast, but fragmented, biochemical literature to reconstruct and analyze the small molecule regulatory network (SMRN) of the model organism Escherichia coli, including the primary metabolite regulators and enzyme targets. Using metabolic control analysis, we prove a fundamental trade-off between regulation and enzymatic activity, and we combine it with metabolomic measurementsmore » and the SMRN to make inferences on the sensitivity of enzymes to their regulators. By generalizing the analysis to other organisms, we identify highly conserved regulatory interactions across evolutionarily divergent species, further emphasizing a critical role for small molecule interactions in the maintenance of metabolic homeostasis.« less

Genome-Scale Architecture of Small Molecule Regulatory Networks and the Fundamental Trade-Off between Regulation and Enzymatic Activity

DOE PAGES

Reznik, Ed; Christodoulou, Dimitris; Goldford, Joshua E.; ...

2017-09-12

Metabolic flux is in part regulated by endogenous small molecules that modulate the catalytic activity of an enzyme, e.g., allosteric inhibition. In contrast to transcriptional regulation of enzymes, technical limitations have hindered the production of a genome-scale atlas of small molecule-enzyme regulatory interactions. Here, we develop a framework leveraging the vast, but fragmented, biochemical literature to reconstruct and analyze the small molecule regulatory network (SMRN) of the model organism Escherichia coli, including the primary metabolite regulators and enzyme targets. Using metabolic control analysis, we prove a fundamental trade-off between regulation and enzymatic activity, and we combine it with metabolomic measurementsmore » and the SMRN to make inferences on the sensitivity of enzymes to their regulators. By generalizing the analysis to other organisms, we identify highly conserved regulatory interactions across evolutionarily divergent species, further emphasizing a critical role for small molecule interactions in the maintenance of metabolic homeostasis.« less

Altered regulation of ELAVL1/HuR in HLA-B27-expressing U937 monocytic cells.

PubMed

Sahlberg, Anna S; Ruuska, Marja; Granfors, Kaisa; Penttinen, Markus A

2013-01-01

To investigate the role of HLA-B27 expression in the regulation of RNA binding protein (RBP) Embryonic Lethal Abnormal Vision (ELAV) L1/Human antigen R (HuR) expression in Salmonella-infected or LPS-stimulated human monocytic cells, since HuR is a critical regulator of the post-transcriptional fate of many genes (e.g. TNFα) important in inflammatory response. U937 monocytic cells were stably transfected with pSV2neo resistant vector (mock), wild type HLA-B27, or mutated HLA-B27 with amino acid substitutions in the B pocket. Cells were differentiated, infected with Salmonella enteritidis or stimulated with lipopolysaccharide. The expression levels of HuR protein and cleavage products (CP1 and CP2) were detected by Western blotting and flow cytometry. Specific inhibitors were used to study the role of PKR and p38 in HuR expression and generation of CPs. TNFα and IL-10 secretion after p38 and PKR inhibition were measured by ELISA. Full length HuR is overexpressed and HuR cleavage is disturbed in U937 monocytic cells expressing HLA-B27 heavy chains (HC). Increased full length HuR expression, disturbed cleavage and reduced dependence on PKR after infection correlate with the expression of glutamic acid 45 in the B pocket that is linked to the misfolding of HLA-B27. Results show that the expression of HLA-B27 HCs modulates the intracellular environment of U937 monocyte/macrophages by altering HuR regulation. This phenomenon is at least partly dependent on the misfolding feature of the B27 molecule. Since HuR is an important regulator of multiple genes involved in inflammatory response observations offer an explanation how HLA-B27 may modulate inflammatory response.

Chromatin remodeling regulates catalase expression during cancer cells adaptation to chronic oxidative stress.

PubMed

Glorieux, Christophe; Sandoval, Juan Marcelo; Fattaccioli, Antoine; Dejeans, Nicolas; Garbe, James C; Dieu, Marc; Verrax, Julien; Renard, Patricia; Huang, Peng; Calderon, Pedro Buc

2016-10-01

Regulation of ROS metabolism plays a major role in cellular adaptation to oxidative stress in cancer cells, but the molecular mechanism that regulates catalase, a key antioxidant enzyme responsible for conversion of hydrogen peroxide to water and oxygen, remains to be elucidated. Therefore, we investigated the transcriptional regulatory mechanism controlling catalase expression in three human mammary cell lines: the normal mammary epithelial 250MK primary cells, the breast adenocarcinoma MCF-7 cells and an experimental model of MCF-7 cells resistant against oxidative stress resulting from chronic exposure to H 2 O 2 (Resox), in which catalase was overexpressed. Here we identify a novel promoter region responsible for the regulation of catalase expression at -1518/-1226 locus and the key molecules that interact with this promoter and affect catalase transcription. We show that the AP-1 family member JunB and retinoic acid receptor alpha (RARα) mediate catalase transcriptional activation and repression, respectively, by controlling chromatin remodeling through a histone deacetylases-dependent mechanism. This regulatory mechanism plays an important role in redox adaptation to chronic exposure to H 2 O 2 in breast cancer cells. Our study suggests that cancer adaptation to oxidative stress may be regulated by transcriptional factors through chromatin remodeling, and reveals a potential new mechanism to target cancer cells. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects of thalidomide on the expression of adhesion molecules in rat liver cirrhosis.

PubMed

Lv, Peng; Paul, Shelley Chireyath; Xiao, Yanjv; Liu, Shiquan; Luo, Hesheng

2006-01-01

This study was to evaluate the effects of thalidomide on expression of adhesion molecules in liver cirrhosis. The cirrhosis was induced in Wistar rats by intraperitoneal injection of CCl(4), and thalidomide (10 mg/kg/day or 100 mg/kg/day) was given by intragastric administration for 8 weeks. Liver histopathology and immunohistochemistry were significantly improved and the expressions of ICAM-1, VCAM-1, E-selectin, and TNF-alpha mRNA and protein were decreased significantly in rats treated with a high dose of thalidomide. Close positive correlation was observed in the expression of the TNF-alpha mRNA and that of ICAM-1, VCAM-1, and E-selectin mRNA, respectively. These results indicate that thalidomide exerts its effect on the downregulation of adhesion molecules via TNF-alpha signaling pathway to inhibit liver fibrosis.

Differential Anoxic Expression of Sugar-Regulated Genes Reveals Diverse Interactions between Sugar and Anaerobic Signaling Systems in Rice

PubMed Central

Lim, Mi-na; Lee, Sung-eun; Yim, Hui-kyeong; Kim, Jeong Hoe; Yoon, In Sun; Hwang, Yong-sic

2013-01-01

The interaction between the dual roles of sugar as a metabolic fuel and a regulatory molecule was unveiled by examining the changes in sugar signaling upon oxygen deprivation, which causes the drastic alteration in the cellular energy status. In our study, the expression of anaerobically induced genes is commonly responsive to sugar, either under the control of hexokinase or non-hexokinase mediated signaling cascades. Only sugar regulation via the hexokinase pathway was susceptible for O2 deficiency or energy deficit conditions evoked by uncoupler. Examination of sugar regulation of those genes under anaerobic conditions revealed the presence of multiple paths underlying anaerobic induction of gene expression in rice, subgrouped into three distinct types. The first of these, which was found in type-1 genes, involved neither sugar regulation nor additional anaerobic induction under anoxia, indicating that anoxic induction is a simple result from the release of sugar repression by O2-deficient conditions. In contrast, type-2 genes also showed no sugar regulation, albeit with enhanced expression under anoxia. Lastly, expression of type-3 genes is highly enhanced with sugar regulation sustained under anoxia. Intriguingly, the inhibition of the mitochondrial ATP synthesis can reproduce expression pattern of a specific set of anaerobically induced genes, implying that rice cells may sense O2 deprivation, partly via perception of the perturbed cellular energy status. Our study of interaction between sugar signaling and anaerobic conditions has revealed that sugar signaling and the cellular energy status are likely to communicate with each other and influence anaerobic induction of gene expression in rice. PMID:23852132

A Bioinformatics Approach Identifies Signal Transducer and Activator of Transcription-3 and Checkpoint Kinase 1 as Upstream Regulators of Kidney Injury Molecule-1 after Kidney Injury

PubMed Central

Ajay, Amrendra Kumar; Kim, Tae-Min; Ramirez-Gonzalez, Victoria; Park, Peter J.; Frank, David A.

2014-01-01

Kidney injury molecule-1 (KIM-1)/T cell Ig and mucin domain-containing protein-1 (TIM-1) is upregulated more than other proteins after AKI, and it is highly expressed in renal damage of various etiologies. In this capacity, KIM-1/TIM-1 acts as a phosphatidylserine receptor on the surface of injured proximal tubular epithelial cells, mediating phagocytosis of apoptotic cells, and it may also act as a costimulatory molecule for immune cells. Despite recognition of KIM-1 as an important therapeutic target for kidney disease, the regulators of KIM-1 transcription in the kidney remain unknown. Using a bioinformatics approach, we identified upstream regulators of KIM-1 after AKI. In response to tubular injury in rat and human kidneys or oxidant stress in human proximal tubular epithelial cells (HPTECs), KIM-1 expression increased significantly in a manner that corresponded temporally and regionally with increased phosphorylation of checkpoint kinase 1 (Chk1) and STAT3. Both ischemic and oxidant stress resulted in a dramatic increase in reactive oxygen species that phosphorylated and activated Chk1, which subsequently bound to STAT3, phosphorylating it at S727. Furthermore, STAT3 bound to the KIM-1 promoter after ischemic and oxidant stress, and pharmacological or genetic induction of STAT3 in HPTECs increased KIM-1 mRNA and protein levels. Conversely, inhibition of STAT3 using siRNAs or dominant negative mutants reduced KIM-1 expression in a kidney cancer cell line (769-P) that expresses high basal levels of KIM-1. These observations highlight Chk1 and STAT3 as critical upstream regulators of KIM-1 expression after AKI and may suggest novel approaches for therapeutic intervention. PMID:24158981

miR-135A Regulates Preimplantation Embryo Development through Down-Regulation of E3 Ubiquitin Ligase Seven in Absentia Homolog 1A (SIAH1A) Expression

PubMed Central

Leung, Carmen O. N.; Ye, Tian-Min; Kwan, Peter C. K.; Lee, Kai-Fai; Yeung, William S. B.

2011-01-01

Background MicroRNAs (miRNAs) are small non-coding RNA molecules capable of regulating transcription and translation. Previously, a cluster of miRNAs that are specifically expressed in mouse zygotes but not in oocytes or other preimplantation stages embryos are identified by multiplex real-time polymerase chain reaction-based miRNA profiling. The functional role of one of these zygote-specific miRNAs, miR-135a, in preimplantation embryo development was investigated. Methodology/Principal Findings Microinjection of miR-135a inhibitor suppressed first cell cleavage in more than 30% of the zygotes. Bioinformatics analysis identified E3 Ubiquitin Ligase Seven In Absentia Homolog 1A (Siah1a) as a predicted target of miR-135a. Western blotting and 3′UTR luciferase functional assays demonstrated that miR-135a down-regulated the expression of Siah1 in HeLa cells and in mouse zygotes. Siah1a was expressed in preimplantation embryos and its expression pattern negatively correlated with that of miR-135a. Co-injection of Siah1a-specific antibody with miR-135a inhibitor partially nullified the effect of miR-135a inhibition. Proteasome inhibition by MG-132 revealed that miR-135a regulated proteasomal degradation and potentially controlled the expression of chemokinesin DNA binding protein (Kid). Conclusions/Significance The present study demonstrated for the first time that zygotic specific miRNA modulates the first cell cleavage through regulating expression of Siah1a. PMID:22132158

Small Molecule Supplements Improve Cultured Megakaryocyte Polyploidization by Modulating Multiple Cell Cycle Regulators.

PubMed

Zou, Xiaojing; Qu, Mingyi; Fang, Fang; Fan, Zeng; Chen, Lin; Yue, Wen; Xie, Xiaoyan; Pei, Xuetao

2017-01-01

Platelets (PLTs) are produced by megakaryocytes (MKs) that completed differentiation and endomitosis. Endomitosis is an important process in which the cell replicates its DNA without cytokinesis and develops highly polyploid MK. In this study, to gain a better PLTs production, four small molecules (Rho-Rock inhibitor (RRI), nicotinamide (NIC), Src inhibitor (SI), and Aurora B inhibitor (ABI)) and their combinations were surveyed as MK culture supplements for promoting polyploidization. Three leukemia cell lines as well as primary mononuclear cells were chosen in the function and mechanism studies of the small molecules. In an optimal culture method, cells were treated with different small molecules and their combinations. The impact of the small molecules on megakaryocytic surface marker expression, polyploidy, proliferation, and apoptosis was examined for the best MK polyploidization supplement. The elaborate analysis confirmed that the combination of SI and RRI together with our MK induction system might result in efficient ploidy promotion. Our experiments demonstrated that, besides direct downregulation on the expression of cytoskeleton protein actin, SI and RRI could significantly enhance the level of cyclins through the suppression of p53 and p21. The verified small molecule combination might be further used in the in vitro PLT manufacture and clinical applications.

Small Molecule Supplements Improve Cultured Megakaryocyte Polyploidization by Modulating Multiple Cell Cycle Regulators

PubMed Central

Fang, Fang; Chen, Lin; Yue, Wen

2017-01-01

Platelets (PLTs) are produced by megakaryocytes (MKs) that completed differentiation and endomitosis. Endomitosis is an important process in which the cell replicates its DNA without cytokinesis and develops highly polyploid MK. In this study, to gain a better PLTs production, four small molecules (Rho-Rock inhibitor (RRI), nicotinamide (NIC), Src inhibitor (SI), and Aurora B inhibitor (ABI)) and their combinations were surveyed as MK culture supplements for promoting polyploidization. Three leukemia cell lines as well as primary mononuclear cells were chosen in the function and mechanism studies of the small molecules. In an optimal culture method, cells were treated with different small molecules and their combinations. The impact of the small molecules on megakaryocytic surface marker expression, polyploidy, proliferation, and apoptosis was examined for the best MK polyploidization supplement. The elaborate analysis confirmed that the combination of SI and RRI together with our MK induction system might result in efficient ploidy promotion. Our experiments demonstrated that, besides direct downregulation on the expression of cytoskeleton protein actin, SI and RRI could significantly enhance the level of cyclins through the suppression of p53 and p21. The verified small molecule combination might be further used in the in vitro PLT manufacture and clinical applications. PMID:29201898

Inhibitory effects of clotrimazole on TNF-alpha-induced adhesion molecule expression and angiogenesis.

PubMed

Thapa, Dinesh; Lee, Jong Suk; Park, Min-A; Cho, Mi-Yeon; Park, Young-Joon; Choi, Han Gon; Jeong, Tae Cheon; Kim, Jung-Ae

2009-04-01

Cell adhesion molecules play a pivotal role in chronic inflammation and pathological angiogenesis. In the present study, we investigated the inhibitory effects of clotrimazole (CLT) on tumor necrosis factor (TNF)-alpha-induced changes in adhesion molecule expression. CLT dose-dependently inhibited monocyte chemoattractant protein-1 (MCP-1), intercellular cell adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) expressions in TNF-alpha-stimulated HT29 colonic epithelial cells. This inhibitory action of CLT correlated with a significant reduction in TNF-alpha-induced adhesion of monocytes to HT29 cells, which was comparable to the inhibitory effects of anti-ICAM-1 and VCAM-1 monoclonal antibodies on monocyte-epithelial adhesion. These inhibitory actions of CLT were, at least in part, attributable to the inhibition of redox sensitive NF-kappaB activation, as CLT inhibited TNF-alpha-induced ROS generation as well as NF-kappaB nuclear translocation and activation in HT29 cells. Furthermore, the inhibition of TNF-alpha-induced monocyte adhesion was also mimicked by the specific NF-kappaB inhibitor, pyrrolidine dithiocarbamate (PDTC). Inflammatory mediators including TNF-alpha have known to promote angiogenesis, which in turn further contributes to inflammatory pathology. Therefore, we additionally evaluated whether CLT modulates TNF-alpha-induced angiogenesis using in vivo chick chorioallantoic membrane (CAM) assay. The CAM assay showed that CLT dose-dependently attenuated TNF-alpha-induced angiogenesis, and the effect was correlated with decreased inflammation of the CAM tissue. In conclusion, our results suggest that CLT can inhibit TNF-alpha-triggered expression of adhesion molecules, ICAM-1 and VCAM-1, and angiogenesis during inflammation.

IL-10-dependent down-regulation of MHC class II expression level on monocytes by peritoneal fluid from endometriosis patients.

PubMed

Lee, Kyu-Sup; Baek, Dae-Won; Kim, Ki-Hyung; Shin, Byoung-Sub; Lee, Dong-Hyung; Kim, Ja-Woong; Hong, Young-Seoub; Bae, Yoe-Sik; Kwak, Jong-Young

2005-11-01

Endometriosis is a gynecologic disorder characterized by the ectopic growth of misplaced endometrial cells. Moreover, immunological abnormalities of cell-mediated and humoral immunity may be associated with the pathogenesis of endometriosis. The effects of peritoneal fluid (PF) from endometriosis patients on the expression levels of MHC class II and costimulatory molecules on the cell surfaces of monocytes were investigated. Compared to the PF of controls, the addition of 10% PF (n=10) from patients with endometriosis to culture medium significantly reduced the percentage of MHC class II-positive cells in cultures of a THP-1, monocytic cell line at 48 h. The effect of endometriosis patient PF (EPF) was dose-dependent, and similar effect was observed in peripheral blood monocytes. An inverse correlation was found between MHC class II expression level and IL-10 concentration in EPF (r=-0.518; p=0.019) and in the supernatant of peripheral blood monocyte cultured in EPF (r=-0.459; p=0.042) (n=20). The expression levels of costimulatory molecules (CD80 and CD86), but not of CD54 and B7-H1, were down-regulated by EPF. The mRNA level of HLA-DR was unaffected by EPF but protein level was reduced by EPF. Neutralizing IL-10 antibody abrogated MHC class II down-regulation on monocytes, which had been induced by EPF. However, in a functional assay, monocytes treated with EPF failed to stimulate T cell in mixed leukocyte reaction, although T cell proliferation was increased with EPF-treated monocytes and Staphylococcus enterotoxin B. These results suggest that MHC class II expression level on monocytes is down-regulated by EPF, but the cell stimulatory ability of monocytes does not coincide with MHC class II expression level.

Corticotropin-Releasing Hormone Modulates Human Trophoblast Invasion through Carcinoembryonic Antigen-Related Cell Adhesion Molecule-1 Regulation

PubMed Central

Bamberger, Ana-Maria; Minas, Vassilis; Kalantaridou, Sophia N.; Radde, Jessica; Sadeghian, Helen; Löning, Thomas; Charalampopoulos, Ioannis; Brümmer, Jens; Wagener, Christoph; Bamberger, Christoph M.; Schulte, Heinrich M.; Chrousos, George P.; Makrigiannakis, Antonis

2006-01-01

Abnormalities in the process of trophoblast invasion may result in abnormal placentation. Both the embryonic trophoblast and maternal decidua produce corticotropin-releasing hormone (CRH), which promotes implantation. Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1), which is expressed in extravillous trophoblasts (EVTs) of normal human placenta, may also function in tro-phoblast/endometrial interactions. We investigated whether locally produced CRH plays a role in trophoblast invasion, primarily by regulating CEACAM1 expression. We examined cultures of freshly isolated human EVTs, which express CEACAM1, and an EVT-based hybridoma cell line, which is devoid of endogenous CEACAM1. CRH inhibited EVT invasion in Matrigel invasion assays, and this effect was blocked by the CRH receptor type 1 (CRHR1)-specific antagonist antalarmin. Additionally, CRH decreased CEACAM1 expression in EVTs in a dose-dependent manner. After transfection of the hybridoma cell line with a CEACAM1 expression vector, the invasiveness of these cells was strongly enhanced. This effect was inhibited by addition of blocking monoclonal antibody against CEACAM1. Furthermore, blocking of endogenous CEACAM1 in EVTs inhibited the invasive potential of these cells. Taken together these findings suggest that CRH inhibits trophoblast invasion by decreasing the expression of CEACAM1 through CRHR1, an effect that might be involved in the pathophysiology of clinical conditions, such as preeclampsia and placenta accreta. PMID:16400017

Cloning of B cell-specific membrane tetraspanning molecule BTS possessing B cell proliferation-inhibitory function.

PubMed

Suenaga, Tadahiro; Arase, Hisashi; Yamasaki, Sho; Kohno, Masayuki; Yokosuka, Tadashi; Takeuchi, Arata; Hattori, Takamichi; Saito, Takashi

2007-11-01

Lymphocyte proliferation is regulated by signals through antigen receptors, co-stimulatory receptors, and other positive and negative modulators. Several membrane tetraspanning molecules are also involved in the regulation of lymphocyte growth and death. We cloned a new B cell-specific tetraspanning (BTS) membrane molecule, which is similar to CD20 in terms of expression, structure and function. BTS is specifically expressed in the B cell line and its expression is increased after the pre-B cell stage. BTS is expressed in intracellular granules and on the cell surface. Overexpression of BTS in immature B cell lines induces growth retardation through inhibition of cell cycle progression and cell size increase without inducing apoptosis. This inhibitory function is mediated predominantly by the N terminus of BTS. The development of mature B cells is inhibited in transgenic mice expressing BTS, suggesting that BTS is involved in the in vivo regulation of B cells. These results indicate that BTS plays a role in the regulation of cell division and B cell growth.

Effects of Thalidomide on the Expression of Adhesion Molecules in Rat Liver Cirrhosis

PubMed Central

Lv, Peng; Paul, Shelley Chireyath; Xiao, Yanjv; Liu, Shiquan; Luo, Hesheng

2006-01-01

This study was to evaluate the effects of thalidomide on expression of adhesion molecules in liver cirrhosis. The cirrhosis was induced in Wistar rats by intraperitoneal injection of CCl4, and thalidomide (10 mg/kg/day or 100 mg/kg/day) was given by intragastric administration for 8 weeks. Liver histopathology and immunohistochemistry were significantly improved and the expressions of ICAM-1, VCAM-1, E-selectin, and TNF-α mRNA and protein were decreased significantly in rats treated with a high dose of thalidomide. Close positive correlation was observed in the expression of the TNF-α mRNA and that of ICAM-1, VCAM-1, and E-selectin mRNA, respectively. These results indicate that thalidomide exerts its effect on the downregulation of adhesion molecules via TNF-α signaling pathway to inhibit liver fibrosis. PMID:17047296

Gonadotropin-releasing hormone regulates expression of the DNA damage repair gene, Fanconi anemia A, in pituitary gonadotroph cells.

PubMed

Larder, Rachel; Chang, Lynda; Clinton, Michael; Brown, Pamela

2004-09-01

Gonadal function is critically dependant on regulated secretion of the gonadotropin hormones from anterior pituitary gonadotroph cells. Gonadotropin biosynthesis and release is triggered by the binding of hypothalamic GnRH to GnRH receptor expressed on the gonadotroph cell surface. The repertoire of regulatory molecules involved in this process are still being defined. We used the mouse L beta T2 gonadotroph cell line, which expresses both gonadotropin hormones, as a model to investigate GnRH regulation of gene expression and differential display reverse transcription-polymerase chain reaction (RT-PCR) to identify and isolate hormonally induced changes. This approach identified Fanconi anemia a (Fanca), a gene implicated in DNA damage repair, as a differentially expressed transcript. Mutations in Fanca account for the majority of cases of Fanconi anemia (FA), a recessively inherited disease identified by congenital defects, bone marrow failure, infertility, and cancer susceptibility. We confirmed expression and hormonal regulation of Fanca mRNA by quantitative RT-PCR, which showed that GnRH induced a rapid, transient increase in Fanca mRNA. Fanca protein was also acutely upregulated after GnRH treatment of L beta T2 cells. In addition, Fanca gene expression was confined to mature pituitary gonadotrophs and adult mouse pituitary and was not expressed in the immature alpha T3-1 gonadotroph cell line. Thus, this study extends the expression profile of Fanca into a highly specialized endocrine cell and demonstrates hormonal regulation of expression of the Fanca locus. We suggest that this regulatory mechanism may have a crucial role in the GnRH-response mechanism of mature gonadotrophs and perhaps the etiology of FA.

Amyloid Precursor-like Protein 2 Association with HLA Class I Molecules

PubMed Central

Tuli, Amit; Sharma, Mahak; Wang, Xiaojian; Simone, Laura C.; Capek, Haley L.; Cate, Steven; Hildebrand, William H.; Naslavsky, Naava; Caplan, Steve; Solheim, Joyce C.

2009-01-01

Amyloid precursor-like protein 2 (APLP2) is a ubiquitously expressed protein. The previously demonstrated functions for APLP2 include binding to the mouse major histocompatibility complex (MHC) class I molecule H-2Kd and down regulating its cell surface expression. In this study, we have investigated the interaction of APLP2 with the human leukocyte antigen (HLA) class I molecule in human tumor cell lines. APLP2 was readily detected in pancreatic, breast, and prostate tumor lines, although it was found only in very low amounts in lymphoma cell lines. In a pancreatic tumor cell line, HLA class I was extensively co-localized with APLP2 in vesicular compartments following endocytosis of HLA class I molecules. In pancreatic, breast, and prostate tumor lines, APLP2 was bound to the HLA class I molecule. APLP2 was found to bind to HLA-A24, and more strongly to HLA-A2. Increased expression of APLP2 resulted in reduced surface expression of HLA-A2 and HLA-A24. Overall, these studies demonstrate that APLP2 binds to the HLA class I molecule, co-localizes with it in intracellular vesicles, and reduces the level of HLA class I molecule cell surface expression. PMID:19184004

Single molecule fluorescence microscopy for ultra-sensitive RNA expression profiling

NASA Astrophysics Data System (ADS)

Hesse, Jan; Jacak, Jaroslaw; Regl, Gerhard; Eichberger, Thomas; Aberger, Fritz; Schlapak, Robert; Howorka, Stefan; Muresan, Leila; Frischauf, Anna-Maria; Schütz, Gerhard J.

2007-02-01

We developed a microarray analysis platform for ultra-sensitive RNA expression profiling of minute samples. It utilizes a novel scanning system for single molecule fluorescence detection on cm2 size samples in combination with specialized biochips, optimized for low autofluorescence and weak unspecific adsorption. 20 μg total RNA was extracted from 10 6 cells of a human keratinocyte cell line (HaCaT) and reversely transcribed in the presence of Alexa647-aha-dUTP. 1% of the resulting labeled cDNA was used for complex hybridization to a custom-made oligonucleotide microarray representing a set of 125 different genes. For low abundant genes, individual cDNA molecules hybridized to the microarray spots could be resolved. Single cDNA molecules hybridized to the chip surface appeared as diffraction limited features in the fluorescence images. The à trous wavelet method was utilized for localization and counting of the separated cDNA signals. Subsequently, the degree of labeling of the localized cDNA molecules was determined by brightness analysis for the different genes. Variations by factors up to 6 were found, which in conventional microarray analysis would result in a misrepresentation of the relative abundance of mRNAs.

Identification of a novel antisense long non-coding RNA PLA2G16-AS that regulates the expression of PLA2G16 in pigs.

PubMed

Liu, Pengliang; Jin, Long; Zhao, Lirui; Long, Keren; Song, Yang; Tang, Qianzi; Ma, Jideng; Wang, Xun; Tang, Guoqing; Jiang, Yanzhi; Zhu, Li; Li, Xuewei; Li, Mingzhou

2018-05-31

Natural antisense transcripts (NATs) are widely present in mammalian genomes and act as pivotal regulator molecules to control gene expression. However, studies on the NATs of pigs are relatively rare. Here, we identified a novel antisense transcript, designated PLA2G16-AS, transcribed from the phospholipase A2 group XVI locus (PLA2G16) in the porcine genome, which is a well-known regulatory molecule of fat deposition. PLA2G16-AS and PLA2G16 were dominantly expressed in porcine adipose tissue, and were differentially expressed between Tibetan pigs and Rongchang pigs. In addition, PLA2G16-AS has a weak sequence conservation among different vertebrates. PLA2G16-AS was also shown to form an RNA-RNA duplex with PLA2G16, and to regulate PLA2G16 expression at the mRNA level. Moreover, the overexpression of PLA2G16-AS increased the stability of PLA2G16 mRNA in porcine cells. We envision that our findings of a NAT for a regulatory gene associated with lipolysis might further our understanding of the molecular regulation of fat deposition. Copyright © 2017. Published by Elsevier B.V.

The cationic small molecule GW4869 is cytotoxic to high phosphatidylserine-expressing myeloma cells.

PubMed

Vuckovic, Slavica; Vandyke, Kate; Rickards, David A; McCauley Winter, Padraig; Brown, Simon H J; Mitchell, Todd W; Liu, Jun; Lu, Jun; Askenase, Philip W; Yuriev, Elizabeth; Capuano, Ben; Ramsland, Paul A; Hill, Geoffrey R; Zannettino, Andrew C W; Hutchinson, Andrew T

2017-05-01

We have discovered that a small cationic molecule, GW4869, is cytotoxic to a subset of myeloma cell lines and primary myeloma plasma cells. Biochemical analysis revealed that GW4869 binds to anionic phospholipids such as phosphatidylserine - a lipid normally confined to the intracellular side of the cell membrane. However, interestingly, phosphatidylserine was expressed on the surface of all myeloma cell lines tested (n = 12) and 9/15 primary myeloma samples. Notably, the level of phosphatidylserine expression correlated well with sensitivity to GW4869. Inhibition of cell surface phosphatidylserine exposure with brefeldin A resulted in resistance to GW4869. Finally, GW4869 was shown to delay the growth of phosphatidylserine-high myeloma cells in vivo. To the best of our knowledge, this is the first example of using a small molecule to target phosphatidylserine on malignant cells. This study may provide the rationale for the development of phosphatidylserine-targeting small molecules for the treatment of surface phosphatidylserine-expressing cancers. © 2017 John Wiley & Sons Ltd.

Differential Regulation of cGMP Signaling in Human Melanoma Cells at Altered Gravity: Simulated Microgravity Down-Regulates Cancer-Related Gene Expression and Motility

NASA Astrophysics Data System (ADS)

Ivanova, Krassimira; Eiermann, Peter; Tsiockas, Wasiliki; Hemmersbach, Ruth; Gerzer, Rupert

2018-03-01

Altered gravity is known to affect cellular function by changes in gene expression and cellular signaling. The intracellular signaling molecule cyclic guanosine-3',5'-monophosphate (cGMP), a product of guanylyl cyclases (GC), e.g., the nitric oxide (NO)-sensitive soluble GC (sGC) or natriuretic peptide-activated GC (GC-A/GC-B), is involved in melanocyte response to environmental stress. NO-sGC-cGMP signaling is operational in human melanocytes and non-metastatic melanoma cells, whereas up-regulated expression of GC-A/GC-B and inducible NO synthase (iNOS) are found in metastatic melanoma cells, the deadliest skin cancer. Here, we investigated the effects of altered gravity on the mRNA expression of NOS isoforms, sGC, GC-A/GC-B and multidrug resistance-associated proteins 4/5 (MRP4/MRP5) as selective cGMP exporters in human melanoma cells with different metastatic potential and pigmentation. A specific centrifuge (DLR, Cologne Germany) was used to generate hypergravity (5 g for 24 h) and a fast-rotating 2-D clinostat (60 rpm) to simulate microgravity values ≤ 0.012 g for 24 h. The results demonstrate that hypergravity up-regulates the endothelial NOS-sGC-MRP4/MRP5 pathway in non-metastatic melanoma cells, but down-regulates it in simulated microgravity when compared to 1 g. Additionally, the suppression of sGC expression and activity has been suggested to correlate inversely to tumor aggressiveness. Finally, hypergravity is ineffective in highly metastatic melanoma cells, whereas simulated microgravity down-regulates predominantly the expression of the cancer-related genes iNOS and GC-A/GC-B (shown additionally on protein levels) as well as motility in comparison to 1 g. The results suggest that future studies in real microgravity can benefit from considering GC-cGMP signaling as possible factor for melanocyte transformation.

Differential expression of MHC class II and B7 costimulatory molecules by microglia in rodent gliomas.

PubMed

Badie, Behnam; Bartley, Becky; Schartner, Jill

2002-12-01

To assess the immune function of microglia and macrophages in brain tumors, the expression of MHC class II and B7 costimulatory molecules in three rodent glioma models was examined. Microglia and macrophages, which accounted for 5-12% of total cells, expressed B7.1 and MHC class II molecules in the C6 and 9L tumors, but not RG2 gliomas. Interestingly, the expression of B7.1 and MHC class II molecules by microglia and macrophage was associated with an increase in the number of tumor-infiltrating lymphocytes in C6 and 9L tumors. B7.2 expression, which was present at low levels on microglia and macrophages in normal brain, did not significantly change in tumors. Interestingly, the expression of all three surface antigens increased after microglia were isolated from intracranial C6 tumors and cultured for a short period of time. We conclude that microglia immune activity may be suppressed in gliomas and directly correlates to the immunogenecity of experimental brain tumors.

Test Review: Anger Regulation and Expression Scale

ERIC Educational Resources Information Center

Cavlazoglu, Baki; Erdogan, Niyazi; Paine, Taylor; Jones, Meredith

2013-01-01

This review focuses on the Anger Regulation and Expression Scale (ARES) which was developed by DiGiuseppe and Tafrate (2011) and published by Multi-Health Systems Inc. The ARES was designed to be a self-report measure of anger expression and regulation in youth aged 10 to 17 years and was intended to be used in screening, individual assessment,…

Apicidin sensitizes pancreatic cancer cells to gemcitabine by epigenetically regulating MUC4 expression.

PubMed

Ansari, Daniel; Urey, Carlos; Hilmersson, Katarzyna Said; Bauden, Monika P; Ek, Fredrik; Olsson, Roger; Andersson, Roland

2014-10-01

Mucin 4 (MUC4) has been linked to resistance to gemcitabine in pancreatic cancer cells. The aim of the present study was to assess whether epigenetic control of MUC4 expression can sensitize pancreatic cancer cells to gemcitabine treatment. A 76-member combined epigenetics and phosphatase small-molecule inhibitor library was screened for anti-proliferative activity against the MUC4(+) gemcitabine-resistant pancreatic cancer cell line Capan-1, followed by high-content screening of protein expression. Apicidin, a histone deacetylase inhibitor, showed the greatest anti-proliferative activity with a lethal dose 50 (LD50) value of 5.17 μM. Apicidin significantly reduced the expression of MUC4 and its transcription factor hepatocyte nuclear factor 4α. Combined treatment with a sub-therapeutic concentration of apicidin and gemcitabine synergistically inhibited growth of Capan-1 cells. Apicidin appears to be a novel anti-proliferative agent against pancreatic cancer cells that may reverse chemoresistance by epigenetically regulating MUC4 expression. Copyright© 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Altered Regulation of ELAVL1/HuR in HLA-B27–Expressing U937 Monocytic Cells

PubMed Central

Sahlberg, Anna S.; Ruuska, Marja; Granfors, Kaisa; Penttinen, Markus A.

2013-01-01

Objective To investigate the role of HLA-B27 expression in the regulation of RNA binding protein (RBP) Embryonic Lethal Abnormal Vision (ELAV) L1/Human antigen R (HuR) expression in Salmonella-infected or LPS-stimulated human monocytic cells, since HuR is a critical regulator of the post-transcriptional fate of many genes (e.g. TNFα) important in inflammatory response. Methods U937 monocytic cells were stably transfected with pSV2neo resistant vector (mock), wild type HLA–B27, or mutated HLA–B27 with amino acid substitutions in the B pocket. Cells were differentiated, infected with Salmonella enteritidis or stimulated with lipopolysaccharide. The expression levels of HuR protein and cleavage products (CP1 and CP2) were detected by Western blotting and flow cytometry. Specific inhibitors were used to study the role of PKR and p38 in HuR expression and generation of CPs. TNFα and IL-10 secretion after p38 and PKR inhibition were measured by ELISA. Results Full length HuR is overexpressed and HuR cleavage is disturbed in U937 monocytic cells expressing HLA-B27 heavy chains (HC). Increased full length HuR expression, disturbed cleavage and reduced dependence on PKR after infection correlate with the expression of glutamic acid 45 in the B pocket that is linked to the misfolding of HLA-B27. Conclusion Results show that the expression of HLA-B27 HCs modulates the intracellular environment of U937 monocyte/macrophages by altering HuR regulation. This phenomenon is at least partly dependent on the misfolding feature of the B27 molecule. Since HuR is an important regulator of multiple genes involved in inflammatory response observations offer an explanation how HLA-B27 may modulate inflammatory response. PMID:23894643

Expressed Glycosylphosphatidylinositol-Anchored Horseradish Peroxidase Identifies Co-Clustering Molecules in Individual Lipid Raft Domains

PubMed Central

Miyagawa-Yamaguchi, Arisa; Kotani, Norihiro; Honke, Koichi

2014-01-01

Lipid rafts that are enriched in glycosylphosphatidylinositol (GPI)-anchored proteins serve as a platform for important biological events. To elucidate the molecular mechanisms of these events, identification of co-clustering molecules in individual raft domains is required. Here we describe an approach to this issue using the recently developed method termed enzyme-mediated activation of radical source (EMARS), by which molecules in the vicinity within 300 nm from horseradish peroxidase (HRP) set on the probed molecule are labeled. GPI-anchored HRP fusion proteins (HRP-GPIs), in which the GPI attachment signals derived from human decay accelerating factor and Thy-1 were separately connected to the C-terminus of HRP, were expressed in HeLa S3 cells, and the EMARS reaction was catalyzed by these expressed HRP-GPIs under a living condition. As a result, these different HRP-GPIs had differences in glycosylation and localization and formed distinct clusters. This novel approach distinguished molecular clusters associated with individual GPI-anchored proteins, suggesting that it can identify co-clustering molecules in individual raft domains. PMID:24671047

Dynamic Regulation of Platelet-Derived Growth Factor Receptor α Expression in Alveolar Fibroblasts during Realveolarization

PubMed Central

Chen, Leiling; Acciani, Thomas; Le Cras, Tim; Lutzko, Carolyn

2012-01-01

Although the importance of platelet-derived growth factor receptor (PDGFR)-α signaling during normal alveogenesis is known, it is unclear whether this signaling pathway can regulate realveolarization in the adult lung. During alveolar development, PDGFR-α–expressing cells induce α smooth muscle actin (α-SMA) and differentiate to interstitial myofibroblasts. Fibroblast growth factor (FGF) signaling regulates myofibroblast differentiation during alveolarization, whereas peroxisome proliferator-activated receptor (PPAR)-γ activation antagonizes myofibroblast differentiation in lung fibrosis. Using left lung pneumonectomy, the roles of FGF and PPAR-γ signaling in differentiation of myofibroblasts from PDGFR-α–positive precursors during compensatory lung growth were assessed. FGF receptor (FGFR) signaling was inhibited by conditionally activating a soluble dominant-negative FGFR2 transgene. PPAR-γ signaling was activated by administration of rosiglitazone. Changes in α-SMA and PDGFR-α protein expression were assessed in PDGFR-α–green fluorescent protein (GFP) reporter mice using immunohistochemistry, flow cytometry, and real-time PCR. Immunohistochemistry and flow cytometry demonstrated that the cell ratio and expression levels of PDGFR-α–GFP changed dynamically during alveolar regeneration and that α-SMA expression was induced in a subset of PDGFR-α–GFP cells. Expression of a dominant-negative FGFR2 and administration of rosiglitazone inhibited induction of α-SMA in PDGFR-α–positive fibroblasts and formation of new septae. Changes in gene expression of epithelial and mesenchymal signaling molecules were assessed after left lobe pneumonectomy, and results demonstrated that inhibition of FGFR2 signaling and increase in PPAR-γ signaling altered the expression of Shh, FGF, Wnt, and Bmp4, genes that are also important for epithelial–mesenchymal crosstalk during early lung development. Our data demonstrate for the first time that a comparable

Cyclosporin A reduces expression of adhesion molecules in the kidney of rats with chronic serum sickness

PubMed Central

Rincón, J; Parra, G; Quiroz, Y; Benatuil, L; Rodríguez-Iturbe, B

2000-01-01

Treatment with cyclosporin A (CsA) improves proteinuria and reduces renal cellular infiltration in chronic serum sickness (CSS). We examined if these effects were associated with a reduced renal expression of CD54 and its ligands, interferon-gamma (IFN-γ), tumour necrosis factor-alpha (TNF-α) and MHC class II molecules. We studied two groups of rats in which CSS was induced by daily injections of ovalbumin (OVA): a group treated with CsA (OVA.CsA group, n = 11) and a group that received no treatment (OVA.CSS group, n = 11). An additional group of five rats (control group) received only phosphate buffer. Immunostaining techniques were used to follow CSS and to study the expression of CD54, CD18, CD11b/c, IFN-γ, TNF-α and MHC class molecules. Proteinuria (mg/24 h) was reduced from 248·2 ± 73·1 (OVA.CCS group) to 14·5 ± 13·1 with CsA treatment (P < 0·0001). The renal expression of CD54 and its ligands (CD18 and CD11b/c) was reduced by 50% to 75%. Correspondingly, there was a 60% to 85% reduction in the number of infiltrating leucocytes. The number of cells expressing TNF-α, IFN-γ and MHC II molecules was also reduced. CsA reduces expression of CD54 and its ligands. This effect is associated with a reduction of cellular infiltration, IFN-γ, TNF-α-producing cells and with MHC II expression in the kidney. These findings suggest that expression of adhesion molecules plays a critical role in CSS and underline the importance of cellular immunity in this experimental model. PMID:10931158

Gonadotropin-Releasing Hormone Regulates Expression of the DNA Damage Repair Gene, Fanconi anemia A, in Pituitary Gonadotroph Cells1

PubMed Central

Larder, Rachel; Chang, Lynda; Clinton, Michael; Brown, Pamela

2007-01-01

Gonadal function is critically dependant on regulated secretion of the gonadotropin hormones from anterior pituitary gonadotroph cells. Gonadotropin biosynthesis and release is triggered by the binding of hypothalamic GnRH to GnRH receptor expressed on the gonadotroph cell surface. The repertoire of regulatory molecules involved in this process are still being defined. We used the mouse LβT2 gonadotroph cell line, which expresses both gonadotropin hormones, as a model to investigate GnRH regulation of gene expression and differential display reverse transcription-polymerase chain reaction (RT-PCR) to identify and isolate hormonally induced changes. This approach identified Fanconi anemia a (Fanca), a gene implicated in DNA damage repair, as a differentially expressed transcript. Mutations in Fanca account for the majority of cases of Fanconi anemia (FA), a recessively inherited disease identified by congenital defects, bone marrow failure, infertility, and cancer susceptibility. We confirmed expression and hormonal regulation of Fanca mRNA by quantitative RT-PCR, which showed that GnRH induced a rapid, transient increase in Fanca mRNA. Fanca protein was also acutely upregulated after GnRH treatment of LβT2 cells. In addition, Fanca gene expression was confined to mature pituitary gonadotrophs and adult mouse pituitary and was not expressed in the immature αT3-1 gonadotroph cell line. Thus, this study extends the expression profile of Fanca into a highly specialized endocrine cell and demonstrates hormonal regulation of expression of the Fanca locus. We suggest that this regulatory mechanism may have a crucial role in the GnRH-response mechanism of mature gonadotrophs and perhaps the etiology of FA. PMID:15128600

Defective expression of apoptosis-related molecules in multiple sclerosis patients is normalized early after autologous haematopoietic stem cell transplantation.

PubMed

de Oliveira, G L V; Ferreira, A F; Gasparotto, E P L; Kashima, S; Covas, D T; Guerreiro, C T; Brum, D G; Barreira, A A; Voltarelli, J C; Simões, B P; Oliveira, M C; de Castro, F A; Malmegrim, K C R

2017-03-01

Defective apoptosis might be involved in the pathogenesis of multiple sclerosis (MS). We evaluated apoptosis-related molecules in MS patients before and after autologous haematopoietic stem cell transplantation (AHSCT) using BCNU, Etoposide, AraC and Melphalan (BEAM) or cyclophosphamide (CY)-based conditioning regimens. Patients were followed for clinical and immunological parameters for 2 years after AHSCT. At baseline, MS patients had decreased proapoptotic BAD, BAX and FASL and increased A1 gene expression when compared with healthy counterparts. In the BEAM group, BAK, BIK, BIM EL , FAS, FASL, A1, BCL2, BCLX L , CFLIP L and CIAP2 genes were up-regulated after AHSCT. With the exception of BIK, BIM EL and A1, all genes reached levels similar to controls at day + 720 post-transplantation. Furthermore, in these patients, we observed increased CD8 + Fas + T cell frequencies after AHSCT when compared to baseline. In the CY group, we observed increased BAX, BCLW, CFLIP L and CIAP1 and decreased BIK and BID gene expressions after transplantation. At day + 720 post-AHSCT, the expression of BAX, FAS, FASL, BCL2, BCLX L and CIAP1 was similar to that of controls. Protein analyses showed increased Bcl-2 expression before transplantation. At 1 year post-AHSCT, expression of Bak, Bim, Bcl-2, Bcl-xL and cFlip-L was decreased when compared to baseline values. In summary, our findings suggest that normalization of apoptosis-related molecules is associated with the early therapeutic effects of AHSCT in MS patients. These mechanisms may be involved in the re-establishment of immune tolerance during the first 2 years post-transplantation. © 2016 British Society for Immunology.

Regulation of DREAM Expression by Group I mGluR

PubMed Central

Lee, Jinu; Kim, Insook; Oh, So Ra; Ko, Suk Jin; Lim, Mi Kyung; Kim, Dong Goo

2011-01-01

DREAM (downstream regulatory element antagonistic modulator) is a calcium-binding protein that regulates dynorphin expression, promotes potassium channel surface expression, and enhances presenilin processing in an expression level-dependent manner. However, no molecular mechanism has yet explained how protein levels of DREAM are regulated. Here we identified group I mGluR (mGluR1/5) as a positive regulator of DREAM protein expression. Overexpression of mGluR1/5 increased the cellular level of DREAM. Up-regulation of DREAM resulted in increased DREAM protein in both the nucleus and cytoplasm, where the protein acts as a transcriptional repressor and a modulator of its interacting proteins, respectively. DHPG (3,5-dihydroxyphenylglycine), a group I mGluR agonist, also up-regulated DREAM expression in cortical neurons. These results suggest that group I mGluR is the first identified receptor that may regulate DREAM activity in neurons. PMID:21660149

Identification of embryonic precursor cells that differentiate into thymic epithelial cells expressing autoimmune regulator

PubMed Central

Takizawa, Nobukazu; Miyauchi, Maki; Yanai, Hiromi; Tateishi, Ryosuke; Shinzawa, Miho; Yoshinaga, Riko; Kurihara, Masaaki; Yasuda, Hisataka; Sakamoto, Reiko; Yoshida, Nobuaki

2016-01-01

Medullary thymic epithelial cells (mTECs) expressing autoimmune regulator (Aire) are critical for preventing the onset of autoimmunity. However, the differentiation program of Aire-expressing mTECs (Aire+ mTECs) is unclear. Here, we describe novel embryonic precursors of Aire+ mTECs. We found the candidate precursors of Aire+ mTECs (pMECs) by monitoring the expression of receptor activator of nuclear factor-κB (RANK), which is required for Aire+ mTEC differentiation. pMECs unexpectedly expressed cortical TEC molecules in addition to the mTEC markers UEA-1 ligand and RANK and differentiated into mTECs in reaggregation thymic organ culture. Introduction of pMECs in the embryonic thymus permitted long-term maintenance of Aire+ mTECs and efficiently suppressed the onset of autoimmunity induced by Aire+ mTEC deficiency. Mechanistically, pMECs differentiated into Aire+ mTECs by tumor necrosis factor receptor-associated factor 6-dependent RANK signaling. Moreover, nonclassical nuclear factor-κB activation triggered by RANK and lymphotoxin-β receptor signaling promoted pMEC induction from progenitors exhibiting lower RANK expression and higher CD24 expression. Thus, our findings identified two novel stages in the differentiation program of Aire+ mTECs. PMID:27401343

Type I interferon regulates pDC maturation and Ly49Q expression.

PubMed

Toma-Hirano, Makiko; Namiki, Sahori; Miyatake, Shoichiro; Arai, Ken-Ichi; Kamogawa-Schifter, Yumiko

2007-10-01

Ly49Q is expressed on peripheral mouse plasmacytoid dendritic cells (pDC). Immature Ly49Q-negative pDC precursors acquire Ly49Q in the bone marrow and then migrate into the periphery. While searching for molecules that regulate pDC maturation, we found that type I interferon (IFN) inhibited Ly49Q acquisition in vitro. Infections that induce type I IFN production by cells other than pDC (a condition mimicked by poly(I:C) injection in vivo) increase the prevalence of Ly49Q(-) pDC in the bone marrow and peripheral lymphoid organs in wild-type but not IFN-alpha/beta receptor knockout BALB/c mice. Moreover, in vivo exposure to type I IFN causes some Ly49Q(-), but not Ly49Q(+), pDC to convert to conventional DC, defined as B220(-) CD11c(+) CD11b(+) cells. These data suggest that type I IFN regulates pDC development and affects their distribution in the body.

Circular RNA: New Regulatory Molecules.

PubMed

Belousova, E A; Filipenko, M L; Kushlinskii, N E

2018-04-01

Circular RNA are a family of covalently closed circular RNA molecules, formed from pre-mRNA of coding genes by means of splicing (canonical and alternative noncanonical splicing). Maturation of circular RNA is regulated by cis- and trans-elements. Complete list of biological functions of these RNA is not yet compiled; however, their capacity to interact with specific microRNA and play a role of a depot attracts the greatest interest. This property makes circular RNA active regulatory transcription factors. Circular RNA have many advantages over their linear analogs: synthesis of these molecules is conservative, they are universal, characterized by clearly determined specificity, and are resistant to exonucleases. In addition, the level of their expression is often higher than that of their linear forms. It should be noted that expression of circular RNA is tissue-specific. Moreover, some correlations between changes in the repertoire and intensity of expression of circular RNA and the development of some pathologies have been detected. Circular RNA have certain advantages and can serve as new biomarkers for the diagnosis, prognosis, and evaluation of response to therapy.

Expression of intercellular adhesion molecule-1 by myofibers in mdx mice.

PubMed

Torres-Palsa, Maria J; Koziol, Matthew V; Goh, Qingnian; Cicinelli, Peter A; Peterson, Jennifer M; Pizza, Francis X

2015-11-01

We investigated the extent to which intercellular adhesion molecule-1 (ICAM-1), a critical protein of the inflammatory response, is expressed in skeletal muscles of mdx mice (a murine model of Duchenne muscular dystrophy). Muscles were collected from control and mdx mice at 2-24 weeks of age and analyzed for ICAM-1 expression by means of Western blot and immunofluorescence. Western blot revealed higher expression of ICAM-1 in mdx compared with control muscles through 24 weeks of age. In contrast to control muscles, ICAM-1 was expressed on the membrane of damaged, regenerating, and normal myofibers of mdx mice. CD11b+ myeloid cells also expressed ICAM-1 in mdx muscles, and CD11b+ cells were closely associated with the membrane of myofibers expressing ICAM-1. These findings support a paradigm in which ICAM-1 and its localization to myofibers in muscles of mdx mice contributes to the dystrophic pathology. © 2015 Wiley Periodicals, Inc.

EXPRESSION OF INTERCELLULAR ADHESION MOLECULE-1 BY MYOFIBERS IN mdx MICE

PubMed Central

TORRES-PALSA, MARIA J.; KOZIOL, MATTHEW V.; GOH, QINGNIAN; CICINELLI, PETER A.; PETERSON, JENNIFER M.; PIZZA, FRANCIS X.

2017-01-01

Introduction We investigated the extent to which intercellular adhesion molecule-1 (ICAM-1), a critical protein of the inflammatory response, is expressed in skeletal muscles of mdx mice (a murine model of Duchenne muscular dystrophy). Methods Muscles were collected from control and mdx mice at 2–24 weeks of age and analyzed for ICAM-1 expression by means of Western blot and immunofluorescence. Results Western blot revealed higher expression of ICAM-1 in mdx compared with control muscles through 24 weeks of age. In contrast to control muscles, ICAM-1 was expressed on the membrane of damaged, regenerating, and normal myofibers of mdx mice. CD11b+ myeloid cells also expressed ICAM-1 in mdx muscles, and CD11b+ cells were closely associated with the membrane of myofibers expressing ICAM-1. Conclusions These findings support a paradigm in which ICAM-1 and its localization to myofibers in muscles of mdx mice contributes to the dystrophic pathology. PMID:25728314

γ-Oryzanol reduces adhesion molecule expression in vascular endothelial cells via suppression of nuclear factor-κB activation.

PubMed

Sakai, Satoshi; Murata, Takahisa; Tsubosaka, Yoshiki; Ushio, Hideki; Hori, Masatoshi; Ozaki, Hiroshi

2012-04-04

γ-Oryzanol (γ-ORZ) is a mixture of phytosteryl ferulates purified from rice bran oil. In this study, we examined whether γ-ORZ represents a suppressive effect on the lipopolysaccharide (LPS)-induced adhesion molecule expression on vascular endothelium. Treatment with LPS elevated the mRNA expression of vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), and E-selectin in bovine aortic endothelial cells (BAECs). Pretreatment with γ-ORZ dose-dependently decreased the LPS-mediated expression of these genes. Western blotting also revealed that pretreatment with γ-ORZ dose-dependently inhibited LPS-induced VCAM-1 expression in human umbilical vein endothelial cells. Consistently, pretreatment with γ-ORZ dose-dependently reduced LPS-induced U937 monocyte adhesion to BAECs. In immunofluorescence, LPS caused nuclear factor-κB (NF-κB) nuclear translocation in 40% of BAECs, which indicates NF-κB activation. Pretreatment with γ-ORZ, as well as its components (cycloartenyl ferulate, ferulic acid, or cycloartenol), dose-dependently inhibited LPS-mediated NF-κB activation. Collectively, our results suggested that γ-ORZ reduced LPS-mediated adhesion molecule expression through NF-κB inhibition in vascular endothelium.

Expression of podocyte-associated molecules in acquired human kidney diseases.

PubMed

Koop, Klaas; Eikmans, Michael; Baelde, Hans J; Kawachi, Hiroshi; De Heer, Emile; Paul, Leendert C; Bruijn, Jan A

2003-08-01

Proteinuria is a poorly understood feature of many acquired renal diseases. Recent studies concerning congenital nephrotic syndromes and findings in genetically modified mice have demonstrated that podocyte molecules make a pivotal contribution to the maintenance of the selective filtration barrier of the normal glomerulus. However, it is unclear what role podocyte molecules play in proteinuria of acquired renal diseases. This study investigated the mRNA and protein expression of several podocyte-associated molecules in acquired renal diseases. Forty-eight patients with various renal diseases were studied, including minimal change nephropathy, focal segmental glomerulosclerosis, IgA nephropathy, lupus nephritis, and diabetic nephropathy, together with 13 kidneys with normal glomerular function. Protein levels of nephrin, podocin, CD2-associated protein, and podocalyxin were investigated using quantitative immunohistochemical assays. Real-time PCR was used to determine the mRNA levels of nephrin, podocin, and podoplanin in microdissected glomeruli. The obtained molecular data were related to electron microscopic ultrastructural changes, in particular foot process width, and to clinical parameters. In most acquired renal diseases, except in IgA nephropathy, a marked reduction was observed at the protein levels of nephrin, podocin, and podocalyxin, whereas an increase of the glomerular mRNA levels of nephrin, podocin, and podoplanin was found, compared with controls. The mean width of the podocyte foot processes was inversely correlated with the protein levels of nephrin (r = -0.443, P < 0.05), whereas it was positively correlated with podoplanin mRNA levels (r = 0.468, P < 0.05) and proteinuria (r = 0.585, P = 0.001). In the diseases studied, the decrease of slit diaphragm proteins was related to the effacement of foot processes and coincided with a rise of the levels of the corresponding mRNA transcripts. This suggests that the alterations in the expression of

Dual role for argonautes in microRNA processing and posttranscriptional regulation of microRNA expression.

PubMed

Diederichs, Sven; Haber, Daniel A

2007-12-14

MicroRNAs are small endogenous noncoding RNAs involved in posttranscriptional gene regulation. During microRNA biogenesis, Drosha and Dicer process the primary transcript (pri-miRNA) through a precursor hairpin (pre-miRNA) to the mature miRNA. The miRNA is incorporated into the RNA-Induced Silencing Complex (RISC) with Argonaute proteins, the effector molecules in RNA interference (RNAi). Here, we show that all Argonautes elevate mature miRNA expression posttranscriptionally, independent of RNase activity. Also, we identify a role for the RISC slicer Argonaute2 (Ago2) in cleaving the pre-miRNA to an additional processing intermediate, termed Ago2-cleaved precursor miRNA or ac-pre-miRNA. This endogenous, on-pathway intermediate results from cleavage of the pre-miRNA hairpin 12 nucleotides from its 3'-end. By analogy to siRNA processing, Ago2 cleavage may facilitate removal of the nicked passenger strand from RISC after maturation. The multiple roles of Argonautes in the RNAi effector phase and miRNA biogenesis and maturation suggest coordinate regulation of microRNA expression and function.

Regulation of B7.1 costimulatory molecule is mediated by the IFN regulatory factor-7 through the activation of JNK in lipopolysaccharide-stimulated human monocytic cells.

PubMed

Lim, Wilfred; Gee, Katrina; Mishra, Sasmita; Kumar, Ashok

2005-11-01

The engagement of CD28 or CTLA-4 with B7.1 provides the essential second costimulatory signal that regulates the development of immune responses, including T cell activation, differentiation, and induction of peripheral tolerance. The signaling molecules and the transcription factors involved in B7.1 regulation are poorly understood. In this study we investigated the role of MAPKs in the regulation of LPS-induced B7.1 expression in human monocytes and the promonocytic THP-1 cells. Our results show that LPS-induced B7.1 expression in monocytic cells did not involve the activation of either p38 or ERKs. Using the JNK-specific inhibitor SP600125, small interfering RNAs specific for JNK1 and JNK2, and agents such as dexamethasone that inhibit JNK activation, we determined that LPS-induced B7.1 expression was regulated by JNK MAPK in both monocytes and THP-1 cells. In addition, we identified a distinct B7.1-responsive element corresponding to the IFN regulatory factor-7 (IRF-7) binding site in the B7.1 promoter responsible for the regulation of LPS-induced B7.1 transcription. Furthermore, SP600125 and dexamethasone inhibited LPS-induced IRF-7 activity. Taken together, these results suggest that LPS-induced B7.1 transcription in human monocytic cells may be regulated by JNK-mediated activation of the IRF-7 transcription factor.

Abscisic acid ameliorates experimental IBD by downregulating cellular adhesion molecule expression and suppressing immune cell infiltration

PubMed Central

Guri, Amir J; Hontecillas, Raquel; Bassaganya-Riera, Josep

2010-01-01

Background & Aims Abscisic acid (ABA) has shown effectiveness in ameliorating inflammation in obesity, diabetes and cardiovascular disease models. The objective of this study was to determine whether ABA prevents or ameliorates experimental inflammatory bowel disease (IBD). Methods C57BL/6J mice were fed diets with or without ABA (100 mg/kg) for 35 days prior to challenge with 2.5% dextran sodium sulfate (DSS). The severity of clinical disease was assessed daily. Colonic mucosal lesions were evaluated by histopathology, and cellular adhesion molecular and inflammatory markers were assayed by real-time quantitative PCR. Flow cytometry was used to quantify leukocyte populations in the blood, spleen, and mesenteric lymph nodes (MLN). The effect of ABA on cytotoxic T-lymphocyte antigen 4 (CTLA-4) expression in splenocytes was also investigated. Results ABA significantly ameliorated disease activity, colitis and reduced colonic leukocyte infiltration and inflammation. These improvements were associated with down-regulation in vascular cell adhesion marker-1 (VCAM-1), E-selectin, and mucosal addressin adhesion marker-1 (MAdCAM-1) expression. ABA also increased CD4+ and CD8+ T-lymphocytes in blood and MLN and regulatory T-cells in blood. In vitro, ABA increased CTLA-4 expression through a PPAR γ-dependent mechanism. Conclusions We conclude that ABA ameliorates gut inflammation by modulating T cell distribution and adhesion molecule expression. PMID:20236740

Activation of MRTF-A–dependent gene expression with a small molecule promotes myofibroblast differentiation and wound healing

PubMed Central

Velasquez, Lissette S.; Sutherland, Lillian B.; Liu, Zhenan; Grinnell, Frederick; Kamm, Kristine E.; Schneider, Jay W.; Olson, Eric N.; Small, Eric M.

2013-01-01

Myocardin-related transcription factors (MRTFs) regulate cellular contractility and motility by associating with serum response factor (SRF) and activating genes involved in cytoskeletal dynamics. We reported previously that MRTF-A contributes to pathological cardiac remodeling by promoting differentiation of fibroblasts to myofibroblasts following myocardial infarction. Here, we show that forced expression of MRTF-A in dermal fibroblasts stimulates contraction of a collagen matrix, whereas contractility of MRTF-A null fibroblasts is impaired under basal conditions and in response to TGF–β1 stimulation. We also identify an isoxazole ring-containing small molecule, previously shown to induce smooth muscle α-actin gene expression in cardiac progenitor cells, as an agonist of myofibroblast differentiation. Isoxazole stimulates myofibroblast differentiation via induction of MRTF-A–dependent gene expression. The MRTF-SRF signaling axis is activated in response to skin injury, and treatment of dermal wounds with isoxazole accelerates wound closure and suppresses the inflammatory response. These results reveal an important role for MRTF-SRF signaling in dermal myofibroblast differentiation and wound healing and suggest that targeting MRTFs pharmacologically may prove useful in treating diseases associated with inappropriate myofibroblast activity. PMID:24082095

Expression of aberrant HLA-B27 molecules is dependent on B27 dosage and peptide supply.

PubMed

McHugh, Kirsty; Rysnik, Oliwia; Kollnberger, Simon; Shaw, Jacqueline; Utriainen, Lotta; Al-Mossawi, Mohammad Hussein; Payeli, Sravan; Belaunzaran, Osiris Marroquin; Milling, Simon; Renner, Christoph; Bowness, Paul

2014-04-01

Cellular expression of non-classical forms of human leukocyte antigen (HLA)-B27 (NC-B27) may be involved in spondyloarthritis (SpA) pathogenesis. We used a novel B27-specific monoclonal antibody, HD6, to ask if B27 transgenic (TG) rat splenocytes express these NC-B27 molecules. We also investigated whether B27-binding peptides could affect the expression and functional immune recognition of HD6-reactive B27 molecules. Splenocytes from B27-TG, B7-TG and non-transgenic rats, and HLA-B27+ cell lines were stained with monoclonal antibodies recognising classical (ME-1, HLA-ABC-m1) and non-classical (HD6, HC10) B27. Cells were further cultured in the presence of HLA-B27-binding peptides, or subjected to brief low pH treatment prior to mAb staining and/or immunoprecipitation or co-culture with KIR3DL2-CD3ε-expressing Jurkat reporter cells. HD6-reactive molecules were detected in the majority of adult B27-TG rat splenocyte cell subsets, increasing with age and concomitant increased B27 expression. HD6 staining was inhibited by incubation with B27-binding peptides and induced by low pH treatment. HD6 staining correlated with KIR3DL2-CD3ε-expressing Jurkat reporter cell activity. Thus, IL-2 production was decreased when B27-expressing antigen-presenting cells were preincubated with B27-binding peptides, but increased following pretreatment with low pH buffer. Surface expression of HD6-reactive B27 molecules on B27-TG rat splenocytes is consistent with a pathogenic role for NC-B27 in SpA. Interaction of NC-B27 with innate immune receptors could be critical in SpA pathogenesis, and we show that this may be influenced by the availability and composition of the B27-binding peptide pool.

CoMFA, LeapFrog and blind docking studies on sulfonanilide derivatives acting as selective aromatase expression regulators.

PubMed

Gueto, Carlos; Torres, Juan; Vivas-Reyes, Ricardo

2009-09-01

Aromatase, the enzyme responsible for estrogen biosynthesis, is an attractive target in the treatment of hormone-dependent breast cancer. In this manuscript, the structure-based drug design approach of sulfonanilide analogues as potential selective aromatase expression regulators (SAERs) is described. Receptor-independent CoMFA (Comparative Molecular Field Analysis) maps were employed for generating a pseudocavity for LeapFrog calculation. A robust model, using 45 and 10 molecules in the training and test sets, respectively, was developed producing statistically significant results with cross-validated and conventional correlation coefficients of 0.656 and 0.956, respectively. This model was used to predict the activity of newly proposed molecules as SAERs candidates being two magnitude orders more potent than the previously reported compounds. Also in the present study, the computational blind docking method using eHiTS is tested on molecules study group and COX-2 enzyme. Future perspectives of the method in the screening of SAERs candidates with no COX-2 inhibitory activity are discussed.

Dragon (repulsive guidance molecule RGMb) inhibits E-cadherin expression and induces apoptosis in renal tubular epithelial cells.

PubMed

Liu, Wenjing; Li, Xiaoling; Zhao, Yueshui; Meng, Xiao-Ming; Wan, Chao; Yang, Baoxue; Lan, Hui-Yao; Lin, Herbert Y; Xia, Yin

2013-11-01

Dragon is one of the three members of the repulsive guidance molecule (RGM) family, i.e. RGMa, RGMb (Dragon), and RGMc (hemojuvelin). We previously identified the RGM members as bone morphogenetic protein (BMP) co-receptors that enhance BMP signaling. Our previous studies found that Dragon is highly expressed in the tubular epithelial cells of mouse kidneys. However, the roles of Dragon in renal epithelial cells are yet to be defined. We now show that overexpression of Dragon increased cell death induced by hypoxia in association with increased cleaved poly(ADP-ribose) polymerase and cleaved caspase-3 levels in mouse inner medullary collecting duct (IMCD3) cells. Dragon also inhibited E-cadherin expression but did not affect epithelial-to-mesenchymal transition induced by TGF-β in IMCD3 cells. Previous studies suggest that the three RGM members can function as ligands for the receptor neogenin. Interestingly, our present study demonstrates that the Dragon actions on apoptosis and E-cadherin expression in IMCD3 cells were mediated by the neogenin receptor but not through the BMP pathway. Dragon expression in the kidney was up-regulated by unilateral ureteral obstruction in mice. Compared with wild-type mice, heterozygous Dragon knock-out mice exhibited 45-66% reduction in Dragon mRNA expression, decreased epithelial apoptosis, and increased tubular E-cadherin expression and had attenuated tubular injury after unilateral ureteral obstruction. Our results suggest that Dragon may impair tubular epithelial integrity and induce epithelial apoptosis both in vitro and in vivo.

Kinesin regulation dynamics through cargo delivery, a single molecule investigation

NASA Astrophysics Data System (ADS)

Kovacs, Anthony; Kessler, Jonathan; Lin, Huawen; Dutcher, Susan; Wang, Yan Mei

2015-03-01

Kinesins are microtubule-based motors that deliver cargo to their destinations in a highly regulated manner. Although in recent years numerous regulators of cargo delivery have been identified, the regulation mechanism of kinesin through the cargo delivery and recycling process is not known. By performing single molecule fluorescence imaging measurements in Chlamydomonas flagella, which are 200 nm in diameter, 10 microns in length, and contain 9 sets of microtubule doublets, we tracked the intraflagellar transport (IFT) trains, BBSome cargo, and kinesin-2 motors through the cargo delivery process and determined the aforementioned dynamics. Upon arrival at the microtubule plus end at the flagellar tip, (1) IFT trains and BBSome cargo remain intact, dissociate together from kinesins and microtubules, and diffuse along flagellar membrane for a mean of 2.3 sec before commencing retrograde travel. (2) Kinesin motors remain bound to and diffuse along microtubules for 1.3 sec before dissociating into the flagellar lumen for recycling.

Identification of Quorum Sensing Signal Molecule of Lactobacillus delbrueckii subsp. bulgaricus.

PubMed

Pang, Xiaoyang; Liu, Cuiping; Lyu, Pengcheng; Zhang, Shuwen; Liu, Lu; Lu, Jing; Ma, Changlu; Lv, Jiaping

2016-12-14

Many bacteria in nature use quorum sensing (QS) to regulate gene expression. The quorum sensing system plays critical roles in the adaptation of bacteria to the surrounding environment. Previous studies have shown that during high-density fermentation, the autolysis of lactic acid bacteria was regulated by the QS system, and the two-component system (TCS, LBUL_RS00115/LBUL_RS00110) is involved in the autolysis of Lactobacillus delbrueckii subsp. bulgaricus. However, the QS signal molecule, which regulates this pathway, has not been identified. In this study, we compared the genome of Lactobacillus bulgaricus ATCC BAA-365 with the locus of seven lactobacillus QS systems; the position of the QS signal molecule of Lactobacillus bulgaricus ATCC BAA-365 was predicted by bioinformatics tool. Its function was identified by in vitro experiments. Construction of TCS mutant by gene knockout of LBUL_RS00115 confirmed that the signal molecule regulates the density of the flora by the TCS (LBUL_RS00115/LBUL_RS00110). This study indicated that quorum quenching and inhibition based on the signal molecule might serve as an approach to reduce the rate of autolysis of LAB and increase the number of live bacteria in fermentation.

Gravity-regulated gene expression in Arabidopsis thaliana

NASA Astrophysics Data System (ADS)

Sederoff, Heike; Brown, Christopher S.; Heber, Steffen; Kajla, Jyoti D.; Kumar, Sandeep; Lomax, Terri L.; Wheeler, Benjamin; Yalamanchili, Roopa

Plant growth and development is regulated by changes in environmental signals. Plants sense environmental changes and respond to them by modifying gene expression programs to ad-just cell growth, differentiation, and metabolism. Functional expression of genes comprises many different processes including transcription, translation, post-transcriptional and post-translational modifications, as well as the degradation of RNA and proteins. Recently, it was discovered that small RNAs (sRNA, 18-24 nucleotides long), which are heritable and systemic, are key elements in regulating gene expression in response to biotic and abiotic changes. Sev-eral different classes of sRNAs have been identified that are part of a non-cell autonomous and phloem-mobile network of regulators affecting transcript stability, translational kinetics, and DNA methylation patterns responsible for heritable transcriptional silencing (epigenetics). Our research has focused on gene expression changes in response to gravistimulation of Arabidopsis roots. Using high-throughput technologies including microarrays and 454 sequencing, we iden-tified rapid changes in transcript abundance of genes as well as differential expression of small RNA in Arabidopsis root apices after minutes of reorientation. Some of the differentially regu-lated transcripts are encoded by genes that are important for the bending response. Functional mutants of those genes respond faster to reorientation than the respective wild type plants, indicating that these proteins are repressors of differential cell elongation. We compared the gravity responsive sRNAs to the changes in transcript abundances of their putative targets and identified several potential miRNA: target pairs. Currently, we are using mutant and transgenic Arabidopsis plants to characterize the function of those miRNAs and their putative targets in gravitropic and phototropic responses in Arabidopsis.

Regulation of voltage-gated sodium channel expression in cancer: hormones, growth factors and auto-regulation

PubMed Central

Fraser, Scott P.; Ozerlat-Gunduz, Iley; Brackenbury, William J.; Fitzgerald, Elizabeth M.; Campbell, Thomas M.; Coombes, R. Charles; Djamgoz, Mustafa B. A.

2014-01-01

Although ion channels are increasingly being discovered in cancer cells in vitro and in vivo, and shown to contribute to different aspects and stages of the cancer process, much less is known about the mechanisms controlling their expression. Here, we focus on voltage-gated Na+ channels (VGSCs) which are upregulated in many types of carcinomas where their activity potentiates cell behaviours integral to the metastatic cascade. Regulation of VGSCs occurs at a hierarchy of levels from transcription to post-translation. Importantly, mainstream cancer mechanisms, especially hormones and growth factors, play a significant role in the regulation. On the whole, in major hormone-sensitive cancers, such as breast and prostate cancer, there is a negative association between genomic steroid hormone sensitivity and functional VGSC expression. Activity-dependent regulation by positive feedback has been demonstrated in strongly metastatic cells whereby the VGSC is self-sustaining, with its activity promoting further functional channel expression. Such auto-regulation is unlike normal cells in which activity-dependent regulation occurs mostly via negative feedback. Throughout, we highlight the possible clinical implications of functional VGSC expression and regulation in cancer. PMID:24493753

Measuring children's regulation of emotion-expressive behavior.

PubMed

Bar-Haim, Yair; Bar-Av, Gali; Sadeh, Avi

2011-04-01

Emotion regulation has become a pivotal concept in developmental and clinical research. However, the measurement of regulatory processes has proved extremely difficult, particularly in the context of within-subject designs. Here, we describe a formal conceptualization and a new experimental procedure, the Balloons Game, to measure a regulatory component of emotion-expressive behavior. We present the internal consistency and stability of the indices derived from the Balloons Game in a sample of 121 kindergarten children. External validation against measures that have been associated with emotion regulation processes is also provided. The findings suggest that the Balloons Game provides a reliable tool for the study of regulation of emotion expression in young children. PsycINFO Database Record (c) 2011 APA, all rights reserved.

Embryonic Explant Culture: Studying Effects of Regulatory Molecules on Gene Expression in Craniofacial Tissues.

PubMed

Närhi, Katja

2017-01-01

The ex vivo culture of embryonic tissue explants permits the continuous monitoring of growth and morphogenesis at specific embryonic stages. The functions of soluble regulatory molecules can be analyzed by introducing them into culture medium or locally with beads to the tissue. Gene expression in the manipulated tissue explants can be analyzed using in situ hybridization, quantitative PCR, and reporter constructs combined to organ culture to examine the functions of the signaling molecules.

Clustering gene expression regulators: new approach to disease subtyping.

PubMed

Pyatnitskiy, Mikhail; Mazo, Ilya; Shkrob, Maria; Schwartz, Elena; Kotelnikova, Ekaterina

2014-01-01

One of the main challenges in modern medicine is to stratify different patient groups in terms of underlying disease molecular mechanisms as to develop more personalized approach to therapy. Here we propose novel method for disease subtyping based on analysis of activated expression regulators on a sample-by-sample basis. Our approach relies on Sub-Network Enrichment Analysis algorithm (SNEA) which identifies gene subnetworks with significant concordant changes in expression between two conditions. Subnetwork consists of central regulator and downstream genes connected by relations extracted from global literature-extracted regulation database. Regulators found in each patient separately are clustered together and assigned activity scores which are used for final patients grouping. We show that our approach performs well compared to other related methods and at the same time provides researchers with complementary level of understanding of pathway-level biology behind a disease by identification of significant expression regulators. We have observed the reasonable grouping of neuromuscular disorders (triggered by structural damage vs triggered by unknown mechanisms), that was not revealed using standard expression profile clustering. For another experiment we were able to suggest the clusters of regulators, responsible for colorectal carcinoma vs adenoma discrimination and identify frequently genetically changed regulators that could be of specific importance for the individual characteristics of cancer development. Proposed approach can be regarded as biologically meaningful feature selection, reducing tens of thousands of genes down to dozens of clusters of regulators. Obtained clusters of regulators make possible to generate valuable biological hypotheses about molecular mechanisms related to a clinical outcome for individual patient.

Clustering Gene Expression Regulators: New Approach to Disease Subtyping

PubMed Central

Pyatnitskiy, Mikhail; Mazo, Ilya; Shkrob, Maria; Schwartz, Elena; Kotelnikova, Ekaterina

2014-01-01

One of the main challenges in modern medicine is to stratify different patient groups in terms of underlying disease molecular mechanisms as to develop more personalized approach to therapy. Here we propose novel method for disease subtyping based on analysis of activated expression regulators on a sample-by-sample basis. Our approach relies on Sub-Network Enrichment Analysis algorithm (SNEA) which identifies gene subnetworks with significant concordant changes in expression between two conditions. Subnetwork consists of central regulator and downstream genes connected by relations extracted from global literature-extracted regulation database. Regulators found in each patient separately are clustered together and assigned activity scores which are used for final patients grouping. We show that our approach performs well compared to other related methods and at the same time provides researchers with complementary level of understanding of pathway-level biology behind a disease by identification of significant expression regulators. We have observed the reasonable grouping of neuromuscular disorders (triggered by structural damage vs triggered by unknown mechanisms), that was not revealed using standard expression profile clustering. For another experiment we were able to suggest the clusters of regulators, responsible for colorectal carcinoma vs adenoma discrimination and identify frequently genetically changed regulators that could be of specific importance for the individual characteristics of cancer development. Proposed approach can be regarded as biologically meaningful feature selection, reducing tens of thousands of genes down to dozens of clusters of regulators. Obtained clusters of regulators make possible to generate valuable biological hypotheses about molecular mechanisms related to a clinical outcome for individual patient. PMID:24416320

Interaction of KLF6 and Sp1 regulates basigin-2 expression mediated proliferation, invasion and metastasis in hepatocellular carcinoma

PubMed Central

Dong, Ya-Lu; Zhang, Jing; Wang, Yong-Qiang; Liu, Lili; Zhang, He-Long; Huang, Jian-Guo; Liao, Cheng-Gong

2016-01-01

Accumulating evidence suggests that the tumor suppressor gene Krüppel-like factor 6 (KLF6) plays important roles in both development and progression of cancer. However, the role of KLF6 in hepatocellular carcinoma (HCC) remains unclear. Cancer-related molecule basigin-2 plays an important role in HCC progression and metastasis. Sp1, one of Sp/KLFs family members, regulates basigin-2 expression in HCC. The involvement of KLFs in basigin-2 regulation and HCC progression and metastasis has not been investigated. We first measured KLF6 expression levels in 50 pairs of HCC and adjacent normal tissues (ANTs) by immunohistochemistry. Specifically, low KLF6 expression but high Sp1 and basigin-2 expression were found in HCC tissues. By contrast, the ANTs showed high KLF6 expression but low Sp1 and basigin-2 expression. Kaplan–Meier analysis showed that higher expression of KLF6 was associated with better overall survival. The survival rate of KLF6-negative patients was lower than that of KLF6-positive patients (P = 0.015). We also found that KLF6 binds to the basigin-2 and Sp1 promoters and decreases their expression. Thus, we identified a microcircuitry mechanism in which KLF6 can repress basigin-2 expression directly by binding to its promoter or indirectly by inhibiting the expression of the transcription factor Sp1 to block gene expression. Additionally, overexpression of KLF6 suppressed the invasion, metastasis and proliferation of HCC cells in vitro and in vivo by targeting basigin-2. Our study provides new evidence that interaction of KLF6 and Sp1 regulates basigin-2 expression in HCC and that KLF6 represses the invasive and metastatic capacities of HCC through basigin-2. PMID:27057625

Preschoolers' Emotion Expression and Regulation: Relations with School Adjustment

ERIC Educational Resources Information Center

Herndon, Kristina J.; Bailey, Craig S.; Shewark, Elizabeth A.; Denham, Susanne A.; Bassett, Hideko H.

2013-01-01

Children's expression and regulation of emotions are building blocks of their experiences in classrooms. Thus, the authors' primary goal was to investigate whether preschoolers' expression or ability to regulate emotions were associated with teachers' ratings of school adjustment. A secondary goal was to investigate how boys and girls differed…

Regulation of neuropeptide Y gene expression in rat brain.

PubMed

Lindefors, N; Brené, S; Herrera-Marschitz, M; Persson, H

1990-01-01

NPY mRNA expression was studied in rat brain using in situ hybridization and RNA blot analysis. Transsynaptic regulation of NPY gene expression was specifically studied in caudate-putamen and frontoparietal (somatosensory) cortex of rats with unilateral lesion of midbrain dopamine neurons and in sham-injected animals. NPY mRNA expression in these two brain regions and the regulation of midbrain dopamine neurons were compared with that of SOM, PPT, CCK and GAD mRNA expression. Neurons expressing NPY and SOM mRNA showed a similar distribution and the expression of both NPY and SOM appears to be regulated by dopamine in a similar fashion. Following a unilateral dopamine deafferentation, the numerical density of both NPY and SOM mRNA expressing neurons almost doubled in the lesioned rat caudate-putamen with no change in the average grain density over positive neurons. Hence, in the intact caudate-putamen dopamine appears to normally suppress expression of these two neuropeptide genes. An activation of both NPY and SOM mRNA expression in many non- or low-expressing neurons is seen when the level of dopamine is decreased. In the frontoparietal cortex, on the other hand, dopamine appears to stimulate NPY and SOM gene expression. RNA blot analysis shows clear-cut changes of NPY mRNA levels in both caudate-putamen and frontoparietal cortex consistent with the changes observed using in situ hybridization. No evidence was found for a change in CCK mRNA expression by the dopamine deafferentation, while PPT mRNA expression decreased in the deafferented caudate-putamen. Consequently, dopamine exerts dissimilar effects on the expression of different neuropeptide genes, that in turn do not respond in the same way in different brain regions. Indirect evidence is also presented indicating that dopamine regulates NPY mRNA expression in a subpopulation of neurons that possibly also express GAD mRNA, both in caudate-putamen and in frontoparietal cortex.

FlavorDB: a database of flavor molecules

PubMed Central

Garg, Neelansh; Sethupathy, Apuroop; Tuwani, Rudraksh; NK, Rakhi; Dokania, Shubham; Iyer, Arvind; Gupta, Ayushi; Agrawal, Shubhra; Singh, Navjot; Shukla, Shubham; Kathuria, Kriti; Badhwar, Rahul; Kanji, Rakesh; Jain, Anupam; Kaur, Avneet; Nagpal, Rashmi

2018-01-01

Abstract Flavor is an expression of olfactory and gustatory sensations experienced through a multitude of chemical processes triggered by molecules. Beyond their key role in defining taste and smell, flavor molecules also regulate metabolic processes with consequences to health. Such molecules present in natural sources have been an integral part of human history with limited success in attempts to create synthetic alternatives. Given their utility in various spheres of life such as food and fragrances, it is valuable to have a repository of flavor molecules, their natural sources, physicochemical properties, and sensory responses. FlavorDB (http://cosylab.iiitd.edu.in/flavordb) comprises of 25,595 flavor molecules representing an array of tastes and odors. Among these 2254 molecules are associated with 936 natural ingredients belonging to 34 categories. The dynamic, user-friendly interface of the resource facilitates exploration of flavor molecules for divergent applications: finding molecules matching a desired flavor or structure; exploring molecules of an ingredient; discovering novel food pairings; finding the molecular essence of food ingredients; associating chemical features with a flavor and more. Data-driven studies based on FlavorDB can pave the way for an improved understanding of flavor mechanisms. PMID:29059383

Identification of small molecules capable of regulating conformational changes of telomeric G-quadruplex

NASA Astrophysics Data System (ADS)

Chen, Shuo-Bin; Liu, Guo-Cai; Gu, Lian-Quan; Huang, Zhi-Shu; Tan, Jia-Heng

2018-02-01

Design of small molecules targeted at human telomeric G-quadruplex DNA is an extremely active research area. Interestingly, the telomeric G-quadruplex is a highly polymorphic structure. Changes in its conformation upon small molecule binding may be a powerful method to achieve a desired biological effect. However, the rational development of small molecules capable of regulating conformational change of telomeric G-quadruplex structures is still challenging. In this study, we developed a reliable ligand-based pharmacophore model based on isaindigotone derivatives with conformational change activity toward telomeric G-quadruplex DNA. Furthermore, virtual screening of database was conducted using this pharmacophore model and benzopyranopyrimidine derivatives in the database were identified as a strong inducer of the telomeric G-quadruplex DNA conformation, transforming it from hybrid-type structure to parallel structure.

Inhibition of TNFα-induced adhesion molecule expression by (Z)-(S)-9-octadecenamide, N-(2-hydroxyethyl,1-methyl).

PubMed

Chen, Caixia; Jin, Xin; Meng, Xianglan; Zheng, Chengwei; Shen, Yanhui; Wang, Yiqing

2011-06-25

Inflammation is a primary event in atherogenesis. Oleoylethanolamide (OEA), a naturally occurring fatty-acid ethanolamide, lowers lipid levels in liver and blood through activation of the nuclear receptor, peroxisome proliferator-activated receptor-alpha (PPARα). We designed and synthesized (Z)-(S)-9-octadecenamide, N-(2-hydroxyethyl, 1-methyl) (OPA), an OEA analog. The present study investigated the effect of OPA on the expression of adhesion molecules in human umbilical vein endothelial cells (HUVEC). OPA inhibited expression of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) stimulated by Tumor Necrosis Factor-α (TNF-α) via activation of PPARα. This inhibition of VCAM-1 and ICAM-1 expression decreased adhesion of monocyte-like cells to stimulated endothelial cells. These results demonstrate that OPA may have anti-inflammatory properties. Our results thus provide new insights into possible future therapeutic approaches to the treatment of atherosclerosis. Copyright © 2011 Elsevier B.V. All rights reserved.

Role of chrysin on expression of insulin signaling molecules

PubMed Central

Satyanarayana, Kottireddy; Sravanthi, Koora; Shaker, Ivvala Anand; Ponnulakshmi, Rajagopal; Selvaraj, Jayaraman

2015-01-01

Background: Currently available drugs are unsuccessful for the treatment of tye-2 diabetes due to their adverseside-effects. Hence, a search for novel drugs, especially ofplant origin, continues. Chrysin (5,7-dihydroxyflavone) is a flavonoid, natural component of traditional medicinal herbs, present in honey, propolis and many plant extracts that hasbeen used in traditional medicine around the world to treat numerous ailments. Objective: The present study was aimed to identify the protective role of chrysin on the expression of insulin-signaling molecules in the skeletal muscle of high fat and sucrose-induced type-2 diabetic adult male rats. Materials and Methods: The oral effective dose of chrysin (100 mg/kg body weight) was given once a day until the end of the study (30 days post-induction of diabetes) to high fat diet-induced diabetic rats. At the end of the experimental period, fasting blood glucose, oral glucose tolerance, serum lipid profile, lipid peroxidation (LPO) and free radical generation, as well as the levels of insulin signaling molecules and tissue glycogen in the gastrocnemius muscle were assessed. Results: Diabetic rats showed impaired glucose tolerance and impairment in insulin signaling molecules (IR, IRS-1, p-IRS-1Tyr632, p- AktThr308), glucose transporter subtype 4 [GLUT4] proteins and glycogen concentration. Serum insulin, lipid profile, LPO and free radical generation were found to be increased in diabetic control rats. The treatment with chrysin normalized the altered levels of blood glucose, serum insulin, lipid profile, LPO and insulin signaling molecules as well as GLUT4 proteins. Conclusion: Our present findings indicate that chrysin improves glycemic control through activation of insulin signal transduction in the gastrocnemius muscle of high fat and sucrose-induced type-2 diabetic male rats. PMID:26834424

Interaction of tumor and host cells with adhesion and extracellular matrix molecules in the development of multiple myeloma.

PubMed

Teoh, G; Anderson, K C

1997-02-01

Adhesion molecules play an important role in the growth regulation and migration of multiple myeloma (MM) cells. They mediate homing of MM cells to the bone marrow and MM cell to bone marrow stromal cell adhesion, with resultant interleukin-6 related autocrine and paracine growth and antiapoptotic affects. Their pattern of expression on tumor cells correlates with the development of plasma cell leukemia or extramedullary disease. Clinically, expression of adhesion molecules on tumor cells or in the serum has already shown prognostic utility. Finally, since adhesion molecules are involved at multiple steps in the pathogenesis of MM, therapeutic studies may target these molecules.

Expression of eukaryotic polypeptides in chloroplasts

DOEpatents

Mayfield, Stephen P.

2013-06-04

The present invention relates to a gene expression system in eukaryotic and prokaryotic cells, preferably plant cells and intact plants. In particular, the invention relates to an expression system having a RB47 binding site upstream of a translation initiation site for regulation of translation mediated by binding of RB47 protein, a member of the poly(A) binding protein family. Regulation is further effected by RB60, a protein disulfide isomerase. The expression system is capable of functioning in the nuclear/cytoplasm of cells and in the chloroplast of plants. Translation regulation of a desired molecule is enhanced approximately 100 fold over that obtained without RB47 binding site activation.

N-MYC down-regulated-like proteins regulate meristem initiation by modulating auxin transport and MAX2 expression.

PubMed

Mudgil, Yashwanti; Ghawana, Sanjay; Jones, Alan M

2013-01-01

N-MYC down-regulated-like (NDL) proteins interact with the Gβ subunit (AGB1) of the heterotrimeric G protein complex and play an important role in AGB1-dependent regulation of lateral root formation by affecting root auxin transport, auxin gradients and the steady-state levels of mRNA encoding the PIN-FORMED 2 and AUXIN 1 auxin transport facilitators. Auxin transport in aerial tissue follows different paths and utilizes different transporters than in roots; therefore, in the present study, we analyzed whether NDL proteins play an important role in AGB1-dependent, auxin-mediated meristem development. Expression levels of NDL gene family members need to be tightly regulated, and altered expression (both over-expression and down-regulation) confers ectopic growth. Over-expression of NDL1 disrupts vegetative and reproductive organ development. Reduced expression of the NDL gene family members results in asymmetric leaf emergence, twinning of rosette leaves, defects in leaf formation, and abnormal silique distribution. Reduced expression of the NDL genes in the agb1-2 (null allele) mutant rescues some of the abnormal phenotypes, such as silique morphology, silique distribution, and peduncle angle, suggesting that proper levels of NDL proteins are maintained by AGB1. We found that all of these abnormal aerial phenotypes due to altered NDL expression were associated with increases in basipetal auxin transport, altered auxin maxima and altered MAX2 expression within the inflorescence stem. NDL proteins, together with AGB1, act as positive regulators of meristem initiation and branching. AGB1 and NDL1 positively regulate basipetal inflorescence auxin transport and modulate MAX2 expression in shoots, which in turn regulates organ and lateral meristem formation by the establishment and maintenance of auxin gradients.

N-MYC DOWN-REGULATED-LIKE Proteins Regulate Meristem Initiation by Modulating Auxin Transport and MAX2 Expression

PubMed Central

Mudgil, Yashwanti; Ghawana, Sanjay; Jones, Alan M.

2013-01-01

Background N-MYC DOWN-REGULATED-LIKE (NDL) proteins interact with the Gβ subunit (AGB1) of the heterotrimeric G protein complex and play an important role in AGB1-dependent regulation of lateral root formation by affecting root auxin transport, auxin gradients and the steady-state levels of mRNA encoding the PIN-FORMED 2 and AUXIN 1 auxin transport facilitators. Auxin transport in aerial tissue follows different paths and utilizes different transporters than in roots; therefore, in the present study, we analyzed whether NDL proteins play an important role in AGB1-dependent, auxin-mediated meristem development. Methodology/Principal Findings Expression levels of NDL gene family members need to be tightly regulated, and altered expression (both over-expression and down-regulation) confers ectopic growth. Over-expression of NDL1 disrupts vegetative and reproductive organ development. Reduced expression of the NDL gene family members results in asymmetric leaf emergence, twinning of rosette leaves, defects in leaf formation, and abnormal silique distribution. Reduced expression of the NDL genes in the agb1-2 (null allele) mutant rescues some of the abnormal phenotypes, such as silique morphology, silique distribution, and peduncle angle, suggesting that proper levels of NDL proteins are maintained by AGB1. We found that all of these abnormal aerial phenotypes due to altered NDL expression were associated with increases in basipetal auxin transport, altered auxin maxima and altered MAX2 expression within the inflorescence stem. Conclusion/Significance NDL proteins, together with AGB1, act as positive regulators of meristem initiation and branching. AGB1 and NDL1 positively regulate basipetal inflorescence auxin transport and modulate MAX2 expression in shoots, which in turn regulates organ and lateral meristem formation by the establishment and maintenance of auxin gradients. PMID:24223735

Identification of small molecule Hes1 modulators as potential anticancer chemotherapeutics.

PubMed

Sail, Vibhavari; Hadden, M Kyle

2013-03-01

Hes1 is a key transcriptional regulator primarily controlled by the Notch signaling pathway, and recent studies have demonstrated both an oncogenic and tumor suppressor role for Hes1, depending on the cell type. Small molecules that activate and inhibit Hes1 activity hold promise as future anticancer chemotherapeutics. We have utilized a cell-based dual luciferase assay to identify modulators of Hes1 expression in a medium-throughput format. A modest screen was performed in HCT-116 colon cancer cell lines, and two small molecules were identified and characterized as Hes1 regulators. Compound 3 induced Hes1 expression and exhibited anticancer effects in pulmonary carcinoid tumor cells, a cell type in which the upregulated Notch/Hes1 signaling plays a tumor suppressive role. Treatment of HCT-116 cells with compound 12 resulted in Hes1 downregulation and antitumor effects. © 2012 John Wiley & Sons A/S.

Inhibition of STAT3 phosphorylation by sulforaphane reduces adhesion molecule expression in vascular endothelial cell.

PubMed

Cho, Young S; Kim, Chan H; Ha, Tae S; Ahn, Hee Y

2015-11-18

Intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) play key roles in the initiation of vascular inflammation. In this study, we explored whether sulforaphane, a dietary phytochemical, can inhibit the expression of ICAM-1 and VCAM-1 in human umbilical vein endothelial cells (HUVEC) stimulated with lipopolysaccharide (LPS), and the mechanisms involved. Sulforaphane prevented the LPS-mediated increase in ICAM-1 and VCAM-1 expression, (P < 0.01) in HUVEC. Sulforaphane also prevented the LPS-mediated increase in the phosphorylation of signal transducer and activator of transcription 3 (STAT3) (P < 0.01). Stattic, a STAT3 inhibitor, reduced the LPS-induced expression of ICAM-1 and VCAM-1, and STAT3 phosphorylation (P < 0.01). STAT3 small interfering RNA treatment reduced the LPS-induced expression of ICAM-1, VCAM-1, and STAT3 (P < 0.01). Sulforaphane reduced LPS-mediated THP-1 monocyte adhesion to HUVEC (P < 0.01). In C57BL/6 mice, injection of LPS increased aortic ICAM-1 and VCAM-1 expression, and this effect was prevented by sulforaphane. These data provide insight into the mechanism through which sulforaphane partly reduces the expression of ICAM-1 and VCAM-1 on the vascular wall by inhibiting STAT3 phosphorylation.

Myostatin regulates proliferation and extracellular matrix mRNA expression in NIH3T3 fibroblasts.

PubMed

Z Hosaka, Yoshinao; Ishibashi, Mika; Wakamatsu, Jun-Ichi; Uehara, Masato; Nishimura, Takanori

2012-12-01

The aim of this study was to clarify the effects of myostatin, which is a negative regulator of skeletal muscle mass, on the proliferation of NIH3T3 fibroblasts and the synthesis of extracellular matrix (ECM) by them. A proliferation assay revealed that myostatin attenuated cell growth at any of the doses used. High doses of myostatin strongly inhibited cell proliferation. Moreover, myostatin receptor, activin receptor type-2B (ActRIIB), was found to be distributed on cells and it was also clarified that myostatin increased the expression of cyclin-dependent kinase inhibitor p21 (p21). These results suggested that a high dose of myostatin inhibits fibroblast proliferation by the same mechanism as that for inhibition of myoblast proliferation. We then examined the effects of myostatin on the mRNA expression of ECM molecules (decorin, biglycan, type I collagen, type III collagen, type IV collagen and type V collagen) by real-time PCR. Real-time PCR showed that myostatin increased the mRNA of decorin, biglycan and collagen (types I, IV and V) in fibroblasts. The results suggest that myostatin regulates ECM synthesis in cultured fibroblasts.

Dragon (Repulsive Guidance Molecule RGMb) Inhibits E-cadherin Expression and Induces Apoptosis in Renal Tubular Epithelial Cells*

PubMed Central

Liu, Wenjing; Li, Xiaoling; Zhao, Yueshui; Meng, Xiao-Ming; Wan, Chao; Yang, Baoxue; Lan, Hui-Yao; Lin, Herbert Y.; Xia, Yin

2013-01-01

Dragon is one of the three members of the repulsive guidance molecule (RGM) family, i.e. RGMa, RGMb (Dragon), and RGMc (hemojuvelin). We previously identified the RGM members as bone morphogenetic protein (BMP) co-receptors that enhance BMP signaling. Our previous studies found that Dragon is highly expressed in the tubular epithelial cells of mouse kidneys. However, the roles of Dragon in renal epithelial cells are yet to be defined. We now show that overexpression of Dragon increased cell death induced by hypoxia in association with increased cleaved poly(ADP-ribose) polymerase and cleaved caspase-3 levels in mouse inner medullary collecting duct (IMCD3) cells. Dragon also inhibited E-cadherin expression but did not affect epithelial-to-mesenchymal transition induced by TGF-β in IMCD3 cells. Previous studies suggest that the three RGM members can function as ligands for the receptor neogenin. Interestingly, our present study demonstrates that the Dragon actions on apoptosis and E-cadherin expression in IMCD3 cells were mediated by the neogenin receptor but not through the BMP pathway. Dragon expression in the kidney was up-regulated by unilateral ureteral obstruction in mice. Compared with wild-type mice, heterozygous Dragon knock-out mice exhibited 45–66% reduction in Dragon mRNA expression, decreased epithelial apoptosis, and increased tubular E-cadherin expression and had attenuated tubular injury after unilateral ureteral obstruction. Our results suggest that Dragon may impair tubular epithelial integrity and induce epithelial apoptosis both in vitro and in vivo. PMID:24052264

Placental Extravillous Cytotrophoblasts Persistently Express Class I Major Histocompatibility Complex Molecules after Human Cytomegalovirus Infection

PubMed Central

Terauchi, Masakazu; Koi, Hideki; Hayano, Chikako; Toyama-Sorimachi, Noriko; Karasuyama, Hajime; Yamanashi, Yuji; Aso, Takeshi; Shirakata, Masaki

2003-01-01

Human cytomegalovirus (HCMV) downregulates the class I major histocompatibility complexes (MHCs), HLA-A and -B, in infected fibroblasts to escape from antigen-specific cytotoxic T lymphocytes. The HCMV genes responsible for the downregulation of MHCs are US2, US3, US6, and US11, which encode type I membrane proteins working at the endoplasmic reticulum (ER). However, it is largely unknown whether HCMV downregulates the class I MHC molecules in placental extravillous cytotrophoblasts (EVT), which express HLA-C, -E, and -G to protect a semiallogenic fetus from maternal natural killer (NK) cells at the fetomaternal interface. Here, we report that differentiated EVT prepared from human first-trimester chorionic villi persistently express class I MHC molecules upon HCMV infection. When these US proteins were expressed in uninfected EVT, they were localized at the ER in the entire cytoplasm. However, subsequent HCMV infection resulted in dissociation of these US proteins from the ER, which relocated toward the cell membrane. In fibroblasts, these US proteins were localized at the ER before and after HCMV infection. These results suggest that the US gene products are not integrated into ER of HCMV-infected EVT and fail to downregulate class I MHC molecules. PMID:12857887

Ankyrin-binding activity of nervous system cell adhesion molecules expressed in adult brain.

PubMed

Davis, J Q; Bennett, V

1993-01-01

A family of ankyrin-binding glycoproteins have been identified in adult rat brain that include alternatively spliced products of the same pre-mRNA. A composite sequence of ankyrin-binding glycoprotein (ABGP) shares 72% amino acid sequence identity with chicken neurofascin, a membrane-spanning neural cell adhesion molecule in the Ig super-family expressed in embryonic brain. ABGP polypeptides and ankyrin associate as pure proteins in a 1:1 molar stoichiometry at a site located in the predicted cytoplasmic domain. ABGP polypeptides are expressed late in postnatal development to approximately the same levels as ankyrin, and comprise a significant fraction of brain membrane proteins. Immunofluorescence studies have shown that ABGP polypeptides are co-localized with ankyrinB. Major differences in developmental expression have been reported for neurofascin in embryos compared with the late postnatal expression of ABGP, suggesting that ABGP and neurofascin represent products of gene duplication events that have subsequently evolved in parallel with distinct roles. Predicted cytoplasmic domains of rat ABGP and chicken neurofascin are nearly identical to each other and closely related to a group of nervous system cell adhesion molecules with variable extracellular domains, including L1, Nr-CAM and Ng-CAM of vertebrates, and neuroglian of Drosophila. A hypothesis to be evaluated is that ankyrin-binding activity is shared by all of these proteins.

Role of an expansin-like molecule in Dictyostelium morphogenesis and regulation of its gene expression by the signal transducer and activator of transcription protein Dd-STATa.

PubMed

Ogasawara, Shun; Shimada, Nao; Kawata, Takefumi

2009-02-01

Expansins are proteins involved in plant morphogenesis, exerting their effects on cellulose to extend cell walls. Dictyostelium is an organism that possesses expansin-like molecules, but their functions are not known. In this study, we analyzed the expL7 (expansin-like 7) gene, which has been identified as a putative target of Dd-STATa, a Dictyostelium homolog of the metazoan signal transducer and activator of transcription (STAT) proteins. Promoter fragments of the expL7 were fused to a lacZ reporter and the expression patterns determined. As expected from the behavior of the endogenous expL7 gene, the expL7/lacZ fusion gene was downregulated in Dd-STATa null slugs. In the parental strain, the expL7 promoter was activated in the anterior tip region. Mutational analysis of the promoter identified a sequence that was necessary for expression in tip cells. In addition, an activator sequence for pstAB cells was identified. These sequences act in combination with the repressor region to prevent ectopic expL7 expression in the prespore and prestalk regions of the slug and culminant. Although the expL7 null mutant showed no phenotypic change, the expL7 overexpressor showed aberrant stalk formation. These results indicate that the expansin-like molecule is important for morphogenesis in Dictyostelium.

Measuring ability to enhance and suppress emotional expression: The Flexible Regulation of Emotional Expression (FREE) Scale.

PubMed

Burton, Charles L; Bonanno, George A

2016-08-01

Flexibility in self-regulatory behaviors has proved to be an important quality for adjusting to stressful life events and requires individuals to have a diverse repertoire of emotion regulation abilities. However, the most commonly used emotion regulation questionnaires assess frequency of behavior rather than ability, with little evidence linking these measures to observable capacity to enact a behavior. The aim of the current investigation was to develop and validate a Flexible Regulation of Emotional Expression (FREE) Scale that measures a person's ability to enhance and suppress displayed emotion across an array of hypothetical contexts. In Studies 1 and 2, a series of confirmatory factor analyses revealed that the FREE Scale consists of 4 first-order factors divided by regulation and emotional valence type that can contribute to 2 higher order factors: expressive enhancement ability and suppression ability. In Study 1, we also compared the FREE Scale to other commonly used emotion regulation measures, which revealed that suppression ability is conceptually distinct from suppression frequency. In Study 3, we compared the FREE Scale with a composite of traditional frequency-based indices of expressive regulation to predict performance in a previously validated emotional modulation paradigm. Participants' enhancement and suppression ability scores on the FREE Scale predicted their corresponding performance on the laboratory task, even when controlling for baseline expressiveness. These studies suggest that the FREE Scale is a valid and flexible measure of expressive regulation ability. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

The postnatal 5-HT1A receptor regulates adult anxiety and depression differently via multiple molecules.

PubMed

Ishikawa, Chihiro; Shiga, Takashi

2017-08-01

Serotonin (5-HT) and the 5-HT 1A receptor during development are known to modulate anxiety and depression in later life. However, the brain mechanisms linking the postnatal 5-HT system and adult behavior remain unknown. Here, we examined the effects of pharmacological 5-HT 1A receptor activation during the postnatal period on anxiety and depression-like behavior in adult BALB/c male mice. To elucidate the underlying mechanisms, we measured mRNA expression of the 5-HT 1A receptor, brain-derived neurotrophic factor (BDNF), GABA A receptor subunits, and AMPA receptor subunits in the medial prefrontal cortex (mPFC), amygdala, and hippocampus. Treatment with the selective 5-HT reuptake inhibitor (fluoxetine) and 5-HT 1A receptor agonist (8-OH-DPAT) during the postnatal period decreased anxiety-like behavior in adulthood, whereas only 8-OH-DPAT treatment increased depression-like behavior. Concomitantly with the behavioral effects, postnatal treatment with fluoxetine and 8-OH-DPAT decreased the mRNA expression of the GABA A receptor α3 subunit in the mPFC and ventral hippocampus in adulthood, while 8-OH-DPAT, but not fluoxetine, decreased the mRNA expression of the 5-HT 1A receptor and BDNF in the mPFC and the GABA A receptor α2 subunit in the mPFC and ventral hippocampus. On the basis of the correlative changes between behavior and mRNA expression, these results suggest that the GABA A receptor α3 subunit in the mPFC and ventral hippocampus may regulate anxiety-like behavior. In contrast, depression-like behavior may be regulated by the 5-HT 1A receptor and BDNF in the mPFC and by the GABA A receptor α2 subunit in the mPFC and ventral hippocampus. In summary, activation of the 5-HT 1A receptor during the postnatal period may reduce anxiety levels, but increase depression levels during adulthood via different multiple molecules in the mPFC and ventral hippocampus. Copyright © 2017 Elsevier Inc. All rights reserved.

Longitudinal associations between physically abusive parents' emotional expressiveness and children's self-regulation.

PubMed

Milojevich, Helen M; Haskett, Mary E

2018-03-01

The present study took a developmental psychopathology approach to examine the longitudinal association between parents' emotional expressiveness and children's self-regulation. Data collection spanned from 2004 to 2008. Ninety-two physically abusive parents completed yearly assessments of their emotional expressiveness, as well as their children's self-regulation abilities. Observational and behavioral measures were also obtained yearly to capture both parents' emotional expressiveness and children's self-regulation. Specifically, parents participated in a parent-child interaction task, which provided insight into their levels of flat affect. A puzzle box task was completed by each child to assess self-regulation. Results indicated, first, that greater parental expression of negative emotions predicted poorer self-regulation in children, both concurrently and across time. Second, parental expressions of positive emotions and parents' flat affect were unrelated to children's self-regulation. Findings inform our understanding of parental socialization of self-regulation and provide insight into the roles of distinct components of emotional expressiveness. Moreover, findings have crucial implications for understanding emotional expressiveness in high-risk samples and increase our understanding of within-group functioning among maltreating families that may serve as a means to direct intervention efforts. Copyright © 2018 Elsevier Ltd. All rights reserved.

Rapamycin (Sirolimus) alters mechanistic target of rapamycin pathway regulation and microRNA expression in mouse meiotic spermatocytes.

PubMed

Mukherjee, A; Koli, S; Reddy, K V R

2015-09-01

Mechanistic target of rapamycin (mTOR) is a signal transduction pathway that modulates translation initiation in several animals including mammals. Rapamaycin, an allosteric inhibitor of mTOR pathway, is often used as an immunosuppressive drug following kidney transplantation and causes gonadal dysfunction and defects in spermatogenesis. The molecular mechanism behind rapamycin-mediated testicular dysfunction is not known. We have therefore explored the contribution of rapamycin in mTOR regulation and microRNA (miRNA) expression in mouse spermatocytes, the intermediate stage of spermatogenesis, where meiosis takes place. In the present study, we optimized the isolation of highly pure and viable spermatocytes by flow sorting, treated them with rapamycin, and investigated the expression of mTOR and downstream effector molecules. Western blot and immunocytochemical analysis confirm that rapamycin treatment suppresses mTOR and phopsphorylated P70S6 kinase activities in spermatocytes, but not that of phosphorylated 4E-binding protein 1. Also, rapamycin treatment modulates the expression of several spermatocyte-specific miRNAs. To complement these finding an in vivo study was also performed. In silico prediction of target genes of these miRNAs and their functional pathway analysis revealed that, several of them are involved in crucial biological process, cellular process and catalytic activities. miRNA-transcription factor (TF) network analysis enlisted different TFs propelling the transcription machineries of these miRNAs. In silico prediction followed by quatitative real-time PCR revealed two of these TFs namely, PU.1 and CCCTC binding factor (CTCF) are down and upregulated, respectively, which may be the reason of the altered expression of miRNAs following rapamycin treatment. In conclusion, for the first time, the present study provides insight into how rapamycin regulates mTOR pathway and spermatocyte-specific miRNA expression which in turn, regulate expression of

The separation between the 5'-3' ends in long RNA molecules is short and nearly constant.

PubMed

Leija-Martínez, Nehemías; Casas-Flores, Sergio; Cadena-Nava, Rubén D; Roca, Joan A; Mendez-Cabañas, José A; Gomez, Eduardo; Ruiz-Garcia, Jaime

2014-12-16

RNA molecules play different roles in coding, decoding and gene expression regulation. Such roles are often associated to the RNA secondary or tertiary structures. The folding dynamics lead to multiple secondary structures of long RNA molecules, since an RNA molecule might fold into multiple distinct native states. Despite an ensemble of different structures, it has been theoretically proposed that the separation between the 5' and 3' ends of long single-stranded RNA molecules (ssRNA) remains constant, independent of their base content and length. Here, we present the first experimental measurements of the end-to-end separation in long ssRNA molecules. To determine this separation, we use single molecule Fluorescence Resonance Energy Transfer of fluorescently end-labeled ssRNA molecules ranging from 500 to 5500 nucleotides in length, obtained from two viruses and a fungus. We found that the end-to-end separation is indeed short, within 5-9 nm. It is remarkable that the separation of the ends of all RNA molecules studied remains small and similar, despite the origin, length and differences in their secondary structure. This implies that the ssRNA molecules are 'effectively circularized' something that might be a general feature of RNAs, and could result in fine-tuning for translation and gene expression regulation. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

Efficacy of an inhibitor of adhesion molecule expression (GI270384X) in the treatment of experimental colitis.

PubMed

Panés, Julián; Aceituno, Montserrat; Gil, Fèlix; Miquel, Rosa; Piqué, Josep M; Salas, Azucena; McLean, Peter

2007-10-01

Modulation of adhesion molecule expression or function is regarded as a promising therapy for inflammatory conditions. This study evaluates the effects of an inhibitor of adhesion molecule expression (GI270384X) in two experimental models of colitis. Colitis of different severity was induced in C57BL/6J mice by administering 1, 2, or 3% dextran sulfate sodium (DSS). GI270384X (3, 10, or 25 mg.kg(-1).day(-1)) was administered as pretreatment or started 3 days after colitis induction. In IL-10-deficient mice, the highest dose was given for 2 wk. The clinical course of colitis, pathological changes, serum inflammatory biomarkers, expression of adhesion molecules, and leukocyte-endothelial cell interactions in colonic venules were measured in mice treated with vehicle or with active drug. In the most severe forms of colitis (2% and 3% DSS and IL-10-deficient mice), the magnitude of colonic inflammation was not modified by treatment with GI270384X. In a less severe form of colitis (1% DSS), GI270384X treatment dose dependently ameliorated the clinical signs of colitis, colonic pathological changes, and serum levels of biomarkers (IL-6 and serum amyloid A). Administration of 25 mg.kg(-1).day(-1) GI270384X abrogated upregulation of ICAM-1 in the inflamed colon but had no effect on VCAM-1 or E-selectin expression. This was associated with a significant reduction in number of rolling and firmly adherent leukocytes in colonic venules. These results indicate that GI270384X is effective in the treatment of experimental colitis of moderate severity. Reduced adhesion molecule expression and leukocyte recruitment to the inflamed intestine contribute to this beneficial effect.

Leukocyte Cell Surface Proteinases: Regulation of Expression, Functions, and Mechanisms of Surface Localization

PubMed Central

Owen, Caroline A.

2008-01-01

A number of proteinases are expressed on the surface of leukocytes including members of the serine, metallo-, and cysteine proteinase superfamilies. Some proteinases are anchored to the plasma membrane of leukocytes by a transmembrane domain or a glycosyl phosphatidyl inositol (GPI) anchor. Other proteinases bind with high affinity to classical receptors, or with lower affinity to integrins, proteoglycans, or other leukocyte surface molecules. Leukocyte surface levels of proteinases are regulated by: 1) cytokines, chemokines, bacterial products, and growth factors which stimulate synthesis and/or release of proteinase by cells; 2) the availability of surface binding sites for proteinases; and/or 3) internalization or shedding of surface-bound proteinases. The binding of proteinases to leukocyte surfaces serves many functions including: 1) concentrating the activity of proteinases to the immediate pericellular environment; 2) facilitating pro-enzyme activation; 3) increasing proteinase stability and retention in the extracellular space; 4) regulating leukocyte function by proteinases signaling through cell surface binding sites or other surface proteins; and 5) protecting proteinases from inhibition by extracellular proteinase inhibitors. There is strong evidence that membrane-associated proteinases on leukocytes play critical roles in wound healing, inflammation, extracellular matrix remodeling, fibrinolysis, and coagulation. This review will outline the biology of membrane-associated proteinases expressed by leukocytes and their roles in physiologic and pathologic processes. PMID:18329945

p63 regulates glutaminase 2 expression

PubMed Central

Giacobbe, Arianna; Bongiorno-Borbone, Lucilla; Bernassola, Francesca; Terrinoni, Alessandro; Markert, Elke Katrin; Levine, Arnold J.; Feng, Zhaohui; Agostini, Massimilano; Zolla, Lello; Agrò, Alessandro Finazzi; Notterman, Daniel A.; Melino, Gerry; Peschiaroli, Angelo

2013-01-01

The transcription factor p63 is critical for many biological processes, including development and maintenance of epidermal tissues and tumorigenesis. Here, we report that the TAp63 isoforms regulate cell metabolism through the induction of the mitochondrial glutaminase 2 (GLS2) gene both in primary cells and tumor cell lines. By ChIP analysis and luciferase assay, we confirmed that TAp63 binds directly to the p53/p63 consensus DNA binding sequence within the GLS2 promoter region. Given the critical role of p63 in epidermal differentiation, we have investigated the regulation of GLS2 expression during this process. GLS2 and TAp63 expression increases during the in vitro differentiation of primary human keratinocytes, and depletion of GLS2 inhibits skin differentiation both at molecular and cellular levels. We found that GLS2 and TAp63 expression are concomitantly induced in cancer cells exposed to oxidative stresses. siRNA-mediated depletion of GLS2 sensitizes cells to ROS-induced apoptosis, suggesting that the TAp63/GLS2 axis can be functionally important as a cellular antioxidant pathway in the absence of p53. Accordingly, we found that GLS2 is upregulated in colon adenocarcinoma. Altogether, our findings demonstrate that GLS2 is a bona fide TAp63 target gene, and that the TAp63-dependent regulation of GLS2 is important for both physiological and pathological processes. PMID:23574722

Amyloid Precursor-like Protein 2 Increases the Endocytosis, Instability, and Turnover of the H2-Kd MHC Class I Molecule1

PubMed Central

Tuli, Amit; Sharma, Mahak; McIlhaney, Mary M.; Talmadge, James E.; Naslavsky, Naava; Caplan, Steve; Solheim, Joyce C.

2008-01-01

The defense against the invasion of viruses and tumors relies on the presentation of viral and tumor-derived peptides to cytotoxic T lymphocytes by cell surface major histocompatibility complex (MHC) class I molecules. Previously, we showed that the ubiquitously expressed protein amyloid precursor-like protein 2 (APLP2) associates with the folded form of the MHC class I molecule Kd. In the current study, APLP2 was found to associate with folded Kd molecules following their endocytosis and to increase the amount of endocytosed Kd. In addition, increased expression of APLP2 was shown to decrease Kd surface expression and thermostability. Correspondingly, Kd thermostability and surface expression were increased by down-regulation of APLP2 expression. Overall, these data suggest that APLP2 modulates the stability and endocytosis of Kd molecules. PMID:18641335

FlavorDB: a database of flavor molecules.

PubMed

Garg, Neelansh; Sethupathy, Apuroop; Tuwani, Rudraksh; Nk, Rakhi; Dokania, Shubham; Iyer, Arvind; Gupta, Ayushi; Agrawal, Shubhra; Singh, Navjot; Shukla, Shubham; Kathuria, Kriti; Badhwar, Rahul; Kanji, Rakesh; Jain, Anupam; Kaur, Avneet; Nagpal, Rashmi; Bagler, Ganesh

2018-01-04

Flavor is an expression of olfactory and gustatory sensations experienced through a multitude of chemical processes triggered by molecules. Beyond their key role in defining taste and smell, flavor molecules also regulate metabolic processes with consequences to health. Such molecules present in natural sources have been an integral part of human history with limited success in attempts to create synthetic alternatives. Given their utility in various spheres of life such as food and fragrances, it is valuable to have a repository of flavor molecules, their natural sources, physicochemical properties, and sensory responses. FlavorDB (http://cosylab.iiitd.edu.in/flavordb) comprises of 25,595 flavor molecules representing an array of tastes and odors. Among these 2254 molecules are associated with 936 natural ingredients belonging to 34 categories. The dynamic, user-friendly interface of the resource facilitates exploration of flavor molecules for divergent applications: finding molecules matching a desired flavor or structure; exploring molecules of an ingredient; discovering novel food pairings; finding the molecular essence of food ingredients; associating chemical features with a flavor and more. Data-driven studies based on FlavorDB can pave the way for an improved understanding of flavor mechanisms. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

Integrin Expression Regulates Neuroblastoma Attachment and Migration1

PubMed Central

Meyer, Amy; van Golen, Cynthia M.; Kim, Bhumsoo; van Golen, Kenneth L.; Feldman, Eva L.

2004-01-01

Abstract Neuroblastoma (NBL) is the most common malignant disease of infancy, and children with bone metastasis have a mortality rate greater than 90%. Two major classes of proteins, integrins and growth factors, regulate the metastatic process. We have previously shown that tumorigenic NBL cells express higher levels of the type I insulin-like growth factor receptor (IGF-IR) and that β1 integrin expression is inversely proportional to tumorigenic potential in NBL. In the current study, we analyze the effect of β1 integrin and IGF-IR on NBL cell attachment and migration. Nontumorigenic S-cells express high levels of β1 integrin, whereas tumorigenic N-cells express little β1 integrin. Alterations in β1 integrin are due to regulation at the protein level, as translation is decreased in N-type cells. Moreover, inhibition of protein synthesis shows that β1 integrin is degraded more slowly in S-type cells (SHEP) than in N-type cells (SH-SY5Y and IMR32). Inhibition of α5β1 integrin prevents SHEP (but not SH-SY5Y or IMR32) cell attachment to fibronectin and increases SHEP cell migration. Increases in IGF-IR decrease β1 integrin expression, and enhance SHEP cell migration, potentially through increased expression of αvβ3. These data suggest that specific classes of integrins in concert with IGF-IR regulate NBL attachment and migration. PMID:15256055

Regulation of the expression of the cell-cycle gene ftsZ by DicF antisense RNA. Division does not require a fixed number of FtsZ molecules.

PubMed

Tétart, F; Bouché, J P

1992-03-01

We show that the 53-nucleotide RNA molecule encoded by gene dicF blocks cell division in Escherichia coli by inhibiting the translation of ftsZ mRNA. Such a role for dicF had been predicted on the basis of the complementarity of DicF RNA with the ribosome-binding region of the ftsZ mRNA. An analysis of ftsZ expression at its chromosomal locus, and of an ftsZ-lacZ translational fusion controlled by promoters ftsZ1p and ftsZ2p only, indicates that ftsZ is not autoregulated. Partial inhibition of FtsZ synthesis leads to increased cell size. However, the number of FtsZ molecules per cell can be reduced threefold without affecting the division rate significantly. Our results suggest that septation is not triggered by a fixed number of newly synthesized FtsZ molecules per cell.

Structural and functional conservation of CLEC-2 with the species-specific regulation of transcript expression in evolution.

PubMed

Wang, Lan; Ren, Shifang; Zhu, Haiyan; Zhang, Dongmei; Hao, Yuqing; Ruan, Yuanyuan; Zhou, Lei; Lee, Chiayu; Qiu, Lin; Yun, Xiaojing; Xie, Jianhui

2012-08-01

CLEC-2 was first identified by sequence similarity to C-type lectin-like molecules with immune functions and has been reported as a receptor for the platelet-aggregating snake venom toxin rhodocytin and the endogenous sialoglycoprotein podoplanin. Recent researches indicate that CLEC-2-deficient mice were lethal at the embryonic stage associated with disorganized and blood-filled lymphatic vessels and severe edema. In view of a necessary role of CLEC-2 in the individual development, it is of interest to investigate its phylogenetic homology and highly conserved functional regions. In this work, we reported that CLEC-2 from different species holds with an extraordinary conservation by sequence alignment and phylogenetic tree analysis. The functional structures including N-linked oligosaccharide sites and ligand-binding domain implement a structural and functional conservation in a variety of species. The glycosylation sites (N120 and N134) are necessary for the surface expression CLEC-2. CLEC-2 from different species possesses the binding activity of mouse podoplanin. Nevertheless, the expression of CLEC-2 is regulated with a species-specific manner. The alternative splicing of pre-mRNA, a regulatory mechanism of gene expression, and the binding sites on promoter for several key transcription factors vary between different species. Therefore, CLEC-2 shares high sequence homology and functional identity. However the transcript expression might be tightly regulated by different mechanisms in evolution.

Altered expression of extracellular matrix molecules and their receptors in chronic pancreatitis and pancreatic adenocarcinoma in comparison with normal pancreas.

PubMed

Shimoyama, S; Gansauge, F; Gansauge, S; Oohara, T; Beger, H G

1995-12-01

The aim of this study was to elucidate the expression and distribution patterns of both integrins and extracellular matrix (ECM) molecules in chronic pancreatitis (CP) and pancreatic adenocarcinoma (PC) compared with normal pancreas (NP). Expression of nine alpha-subunits (alpha 2-alpha 6, alpha V, alpha L, alpha M, and alpha X), four beta-subunits (beta 1, beta 3-beta 5), and four ECM molecules (type IV collagen, laminin, fibronectin, and vitronectin) was investigated immunohistochemically. In CP, all integrins except alpha V showed nearly the same staining patterns compared with NP. Some acinar cells in CP expressed alpha V. Whereas alpha 2, alpha 3, and alpha 6 expression was stronger and diffuse, no alpha 5 expression was seen in PC. Basement membrane (BM) showed continuous staining in CP, whereas it showed discontinuous/absent staining in PC with antitype IV collagen, laminin, and vitronectin antibodies. Some carcinoma cells showed reverse correlation between alpha 2, alpha 3, and alpha 6 expression and type IV collagen and laminin expression. Fibronectin showed diffuse stromal expression in CP and PC. Some acinar cells or duct cells in CP carcinoma cells in PC showed intracellular VN expression. These results suggest that these integrins and ECM molecules are involved in inflammatory and malignant processes in pancreas.

The mouse tumor cell lines EL4 and RMA display mosaic expression of NK-related and certain other surface molecules and appear to have a common origin.

PubMed

Gays, F; Unnikrishnan, M; Shrestha, S; Fraser, K P; Brown, A R; Tristram, C M; Chrzanowska-Lightowlers, Z M; Brooks, C G

2000-05-15

As a potential means for facilitating studies of NK cell-related molecules, we examined the expression of these molecules on a range of mouse tumor cell lines. Of the lines we initially examined, only EL4 and RMA expressed such molecules, both lines expressing several members of the Ly49 and NKRP1 families. Unexpectedly, several of the NK-related molecules, together with certain other molecules including CD2, CD3, CD4, CD32, and CD44, were often expressed in a mosaic manner, even on freshly derived clones, indicating frequent switching in expression. In each case examined, switching was controlled at the mRNA level, with expression of CD3zeta determining expression of the entire CD3-TCR complex. Each of the variable molecules was expressed independently, with the exception that CD3 was restricted to cells that also expressed CD2. Treatment with drugs that affect DNA methylation and histone acetylation could augment the expression of at least some of the variable molecules. The striking phenotypic similarity between EL4 and RMA led us to examine the state of their TCRbeta genes. Both lines had identical rearrangements on both chromosomes, indicating that RMA is in fact a subline of EL4. Overall, these findings suggest that EL4 is an NK-T cell tumor that may have retained a genetic mechanism that permits the variable expression of a restricted group of molecules involved in recognition and signaling.

Nipbl and mediator cooperatively regulate gene expression to control limb development.

PubMed

Muto, Akihiko; Ikeda, Shingo; Lopez-Burks, Martha E; Kikuchi, Yutaka; Calof, Anne L; Lander, Arthur D; Schilling, Thomas F

2014-09-01

Haploinsufficiency for Nipbl, a cohesin loading protein, causes Cornelia de Lange Syndrome (CdLS), the most common "cohesinopathy". It has been proposed that the effects of Nipbl-haploinsufficiency result from disruption of long-range communication between DNA elements. Here we use zebrafish and mouse models of CdLS to examine how transcriptional changes caused by Nipbl deficiency give rise to limb defects, a common condition in individuals with CdLS. In the zebrafish pectoral fin (forelimb), knockdown of Nipbl expression led to size reductions and patterning defects that were preceded by dysregulated expression of key early limb development genes, including fgfs, shha, hand2 and multiple hox genes. In limb buds of Nipbl-haploinsufficient mice, transcriptome analysis revealed many similar gene expression changes, as well as altered expression of additional classes of genes that play roles in limb development. In both species, the pattern of dysregulation of hox-gene expression depended on genomic location within the Hox clusters. In view of studies suggesting that Nipbl colocalizes with the mediator complex, which facilitates enhancer-promoter communication, we also examined zebrafish deficient for the Med12 Mediator subunit, and found they resembled Nipbl-deficient fish in both morphology and gene expression. Moreover, combined partial reduction of both Nipbl and Med12 had a strongly synergistic effect, consistent with both molecules acting in a common pathway. In addition, three-dimensional fluorescent in situ hybridization revealed that Nipbl and Med12 are required to bring regions containing long-range enhancers into close proximity with the zebrafish hoxda cluster. These data demonstrate a crucial role for Nipbl in limb development, and support the view that its actions on multiple gene pathways result from its influence, together with Mediator, on regulation of long-range chromosomal interactions.

Cell adhesion molecules expression pattern indicates that somatic cells arbitrate gonadal sex of differentiating bipotential fetal mouse gonad.

PubMed

Piprek, Rafal P; Kolasa, Michal; Podkowa, Dagmara; Kloc, Malgorzata; Kubiak, Jacek Z

2017-10-01

Unlike other organ anlagens, the primordial gonad is sexually bipotential in all animals. In mouse, the bipotential gonad differentiates into testis or ovary depending on the genetic sex (XY or XX) of the fetus. During gonad development cells segregate, depending on genetic sex, into distinct compartments: testis cords and interstitium form in XY gonad, and germ cell cysts and stroma in XX gonad. However, our knowledge of mechanisms governing gonadal sex differentiation remains very vague. Because it is known that adhesion molecules (CAMs) play a key role in organogenesis, we suspected that diversified expression of CAMs should also play a crucial role in gonad development. Using microarray analysis we identified 129 CAMs and factors regulating cell adhesion during sexual differentiation of mouse gonad. To identify genes expressed differentially in three cell lines in XY and XX gonads: i) supporting (Sertoli or follicular cells), ii) interstitial or stromal cells, and iii) germ cells, we used transgenic mice expressing EGFP reporter gene and FACS cell sorting. Although a large number of CAMs expressed ubiquitously, expression of certain genes was cell line- and genetic sex-specific. The sets of CAMs differentially expressed in supporting versus interstitial/stromal cells may be responsible for segregation of these two cell lines during gonadal development. There was also a significant difference in CAMs expression pattern between XY supporting (Sertoli) and XX supporting (follicular) cells but not between XY and XX germ cells. This indicates that differential CAMs expression pattern in the somatic cells but not in the germ line arbitrates structural organization of gonadal anlagen into testis or ovary. Copyright © 2017 Elsevier B.V. All rights reserved.

Both positive and negative effects on immune responses by expression of a second class II MHC molecule.

PubMed

Ni, Peggy P; Wang, Yaming; Allen, Paul M

2014-11-01

It is perplexing why vertebrates express a limited number of major histocompatibility complex (MHC) molecules when theoretically, having a greater repertoire of MHC molecules would increase the number of epitopes presented, thereby enhancing thymic selection and T cell response to pathogens. It is possible that any positive effects would either be neutralized or outweighed by negative selection restricting the T cell repertoire. We hypothesize that the limit on MHC number is due to negative consequences arising from expressing additional MHC. We compared T cell responses between B6 mice (I-A(+)) and B6.E(+) mice (I-A(+), I-E(+)), the latter expressing a second class II MHC molecule, I-E(b), due to a monomorphic Eα(k) transgene that pairs with the endogenous I-Eβ(b) chain. First, the naive T cell Vβ repertoire was altered in B6.E(+) thymi and spleens, potentially mediating different outcomes in T cell reactivity. Although the B6 and B6.E(+) responses to hen egg-white lysozyme (HEL) protein immunization remained similar, other immune models yielded differences. For viral infection, the quality of the T cell response was subtly altered, with diminished production of certain cytokines by B6.E(+) CD4(+) T cells. In alloreactivity, the B6.E(+) T cell response was significantly dampened. Finally, we observed markedly enhanced susceptibility to experimental autoimmune encephalomyelitis (EAE) in B6.E(+) mice. This correlated with decreased percentages of nTreg cells, supporting the concept of Tregs exhibiting differential susceptibility to negative selection. Altogether, our data suggest that expressing an additional class II MHC can produce diverse effects, with more severe autoimmunity providing a compelling explanation for limiting the expression of MHC molecules. Copyright © 2014 Elsevier Ltd. All rights reserved.

Prolactin--a novel neuroendocrine regulator of human keratin expression in situ.

PubMed

Ramot, Yuval; Bíró, Tamás; Tiede, Stephan; Tóth, Balázs I; Langan, Ewan A; Sugawara, Koji; Foitzik, Kerstin; Ingber, Arieh; Goffin, Vincent; Langbein, Lutz; Paus, Ralf

2010-06-01

The controls of human keratin expression in situ remain to be fully elucidated. Here, we have investigated the effects of the neurohormone prolactin (PRL) on keratin expression in a physiologically and clinically relevant test system: organ-cultured normal human hair follicles (HFs). Not only do HFs express a wide range of keratins, but they are also a source and target of PRL. Microarray analysis revealed that PRL differentially regulated a defined subset of keratins and keratin-associated proteins. Quantitative immunohistomorphometry and quantitative PCR confirmed that PRL up-regulated expression of keratins K5 and K14 and the epithelial stem cell-associated keratins K15 and K19 in organ-cultured HFs and/or isolated HF keratinocytes. PRL also up-regulated K15 promoter activity and K15 protein expression in situ, whereas it inhibited K6 and K31 expression. These regulatory effects were reversed by a pure competitive PRL receptor antagonist. Antagonist alone also modulated keratin expression, suggesting that "tonic stimulation" by endogenous PRL is required for normal expression levels of selected keratins. Therefore, our study identifies PRL as a major, clinically relevant, novel neuroendocrine regulator of both human keratin expression and human epithelial stem cell biology in situ.

Cytotoxicity, oxidative stress and expression of adhesion molecules in human umbilical vein endothelial cells exposed to dust from paints with or without nanoparticles.

PubMed

Mikkelsen, Lone; Jensen, Keld A; Koponen, Ismo K; Saber, Anne T; Wallin, Håkan; Loft, Steffen; Vogel, Ulla; Møller, Peter

2013-03-01

Nanoparticles in primary form and nanoproducts might elicit different toxicological responses. We compared paint-related nanoparticles with respect to effects on endothelial oxidative stress, cytotoxicity and cell adhesion molecule expression. Primary human umbilical vein endothelial cells were exposed to primary nanoparticles (fine, photocatalytic or nanosized TiO(2), aluminium silicate, carbon black, nano-silicasol or axilate) and dust from sanding reference- or nanoparticle-containing paints. Most of the samples increased cell surface expressions of vascular cell adhesion molecule-1 (VCAM-1) and intracellular adhesion molecule-1 (ICAM-1), but paint sanding dust samples generally generated less response than primary particles of TiO(2) and carbon black. We found no relationship between the expression of adhesion molecules, cytotoxicity and production of reactive oxygen species. In conclusion, sanding dust from nanoparticle-containing paint did not generate more oxidative stress or expression of cell adhesion molecules than sanding dust from paint without nanoparticles, whereas the primary particles had the largest effect on mass basis.

Cell Surface Galectin-9 Expressing Th Cells Regulate Th17 and Foxp3+ Treg Development by Galectin-9 Secretion

PubMed Central

Niki, Toshiro; Kadowaki, Takeshi; Ueno, Masaki; Nishi, Nozomu; Yamauchi, Akira; Hattori, Toshio; Masaki, Tsutomu; Hirashima, Mitsuomi

2012-01-01

Galectin-9 (Gal-9), a β-galactoside binding mammalian lectin, regulates immune responses by reducing pro-inflammatory IL-17-producing Th cells (Th17) and increasing anti-inflammatory Foxp3+ regulatory T cells (Treg) in vitro and in vivo. These functions of Gal-9 are thought to be exerted by binding to receptor molecules on the cell surface. However, Gal-9 lacks a signal peptide for secretion and is predominantly located in the cytoplasm, which raises questions regarding how and which cells secrete Gal-9 in vivo. Since Gal-9 expression does not necessarily correlate with its secretion, Gal-9-secreting cells in vivo have been elusive. We report here that CD4 T cells expressing Gal-9 on the cell surface (Gal-9+ Th cells) secrete Gal-9 upon T cell receptor (TCR) stimulation, but other CD4 T cells do not, although they express an equivalent amount of intracellular Gal-9. Gal-9+ Th cells expressed interleukin (IL)-10 and transforming growth factor (TGF)-β but did not express Foxp3. In a co-culture experiment, Gal-9+ Th cells regulated Th17/Treg development in a manner similar to that by exogenous Gal-9, during which the regulation by Gal-9+ Th cells was shown to be sensitive to a Gal-9 antagonist but insensitive to IL-10 and TGF-β blockades. Further elucidation of Gal-9+ Th cells in humans indicates a conserved role of these cells through evolution and implies the possible utility of these cells for diagnosis or treatment of immunological diseases. PMID:23144904

Environmental contaminants and microRNA regulation: Transcription factors as regulators of toxicant-altered microRNA expression

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

Sollome, James; Martin, Elizabeth

MicroRNAs (miRNAs) regulate gene expression by binding mRNA and inhibiting translation and/or inducing degradation of the associated transcripts. Expression levels of miRNAs have been shown to be altered in response to environmental toxicants, thus impacting cellular function and influencing disease risk. Transcription factors (TFs) are known to be altered in response to environmental toxicants and play a critical role in the regulation of miRNA expression. To date, environmentally-responsive TFs that are important for regulating miRNAs remain understudied. In a state-of-the-art analysis, we utilized an in silico bioinformatic approach to characterize potential transcriptional regulators of environmentally-responsive miRNAs. Using the miRStart database,more » genomic sequences of promoter regions for all available human miRNAs (n = 847) were identified and promoter regions were defined as − 1000/+500 base pairs from the transcription start site. Subsequently, the promoter region sequences of environmentally-responsive miRNAs (n = 128) were analyzed using enrichment analysis to determine overrepresented TF binding sites (TFBS). While most (56/73) TFs differed across environmental contaminants, a set of 17 TFs was enriched for promoter binding among miRNAs responsive to numerous environmental contaminants. Of these, one TF was common to miRNAs altered by the majority of environmental contaminants, namely SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily A, member 3 (SMARCA3). These identified TFs represent candidate common transcriptional regulators of miRNAs perturbed by environmental toxicants. - Highlights: • Transcription factors that regulate environmentally-modulated miRNA expression are understudied • Transcription factor binding sites (TFBS) located within DNA promoter regions of miRNAs were identified. • Specific transcription factors may serve as master regulators of environmentally-mediated microRNA expression.« less

ILK mediates LPS-induced vascular adhesion receptor expression and subsequent leucocyte trans-endothelial migration.

PubMed

Hortelano, Sonsoles; López-Fontal, Raquel; Través, Paqui G; Villa, Natividad; Grashoff, Carsten; Boscá, Lisardo; Luque, Alfonso

2010-05-01

The inflammatory response to injurious agents is tightly regulated to avoid adverse consequences of inappropriate leucocyte accumulation or failed resolution. Lipopolysaccharide (LPS)-activated endothelium recruits leucocytes to the inflamed tissue through controlled expression of membrane-associated adhesion molecules. LPS responses in macrophages are known to be regulated by integrin-linked kinase (ILK); in this study, we investigated the role of ILK in the regulation of the LPS-elicited inflammatory response in endothelium. This study was performed on immortalized mouse endothelial cells (EC) isolated from lung and coronary vasculature. Cells were thoroughly characterized and the role of ILK in the regulation of the LPS response was investigated by suppressing ILK expression using siRNA and shRNA technologies. Phenotypic and functional analyses confirmed that the immortalized cells behaved as true EC. LPS induced the expression of the inflammatory genes E-selectin, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1). ILK knockdown impaired LPS-mediated endothelial activation by preventing the induction of ICAM-1 and VCAM-1. Blockade of the LPS-induced response inhibited the inflammatory-related processes of firm adhesion and trans-endothelial migration of leucocytes. ILK is involved in the expression of cell adhesion molecules by EC activated with the inflammatory stimulus LPS. This reduced expression modulates leucocyte adhesion to the endothelium and the extravasation process. This finding suggests ILK as a potential anti-inflammatory target for the development of vascular-specific treatments for inflammation-related diseases.

Circular RNAs: analysis, expression and potential functions

PubMed Central

Salzman, Julia

2016-01-01

Just a few years ago, it had been assumed that the dominant RNA isoforms produced from eukaryotic genes were variants of messenger RNA, functioning as intermediates in gene expression. In early 2012, however, a surprising discovery was made: circular RNA (circRNA) was shown to be a transcriptional product in thousands of human and mouse genes and in hundreds of cases constituted the dominant RNA isoform. Subsequent studies revealed that the expression of circRNAs is developmentally regulated, tissue and cell-type specific, and shared across the eukaryotic tree of life. These features suggest important functions for these molecules. Here, we describe major advances in the field of circRNA biology, focusing on the regulation of and functional roles played by these molecules. PMID:27246710

RepSox improves viability and regulates gene expression in rhesus monkey-pig interspecies cloned embryos.

PubMed

Zhu, Hai-Ying; Jin, Long; Guo, Qing; Luo, Zhao-Bo; Li, Xiao-Chen; Zhang, Yu-Chen; Xing, Xiao-Xu; Xuan, Mei-Fu; Zhang, Guang-Lei; Luo, Qi-Rong; Wang, Jun-Xia; Cui, Cheng-Du; Li, Wen-Xue; Cui, Zheng-Yun; Yin, Xi-Jun; Kang, Jin-Dan

2017-05-01

To investigate the effect of the small molecule, RepSox, on the expression of developmentally important genes and the pre-implantation development of rhesus monkey-pig interspecies somatic cell nuclear transfer (iSCNT) embryos. Rhesus monkey cells expressing the monomeric red fluorescent protein 1 which have a normal (42) chromosome complement, were used as donor cells to generate iSCNT embryos. RepSox increased the expression levels of the pluripotency-related genes, Oct4 and Nanog (p < 0.05), but not of Sox2 compared with untreated embryos at the 2-4-cell stage. Expression of the anti-apoptotic gene, Bcl2, and the pro-apoptotic gene Bax was also affected at the 2-4-cell stage. RepSox treatment also increased the immunostaining intensity of Oct4 at the blastocyst stage (p < 0.05). Although the blastocyst developmental rate was higher in the group treated with 25 µM RepSox for 24 h than in the untreated control group (2.4 vs. 1.2%, p > 0.05), this was not significant. RepSox can improve the developmental potential of rhesus monkey-pig iSCNT embryos by regulating the expression of pluripotency-related genes.

Cobra CRISP functions as an inflammatory modulator via a novel Zn2+- and heparan sulfate-dependent transcriptional regulation of endothelial cell adhesion molecules.

PubMed

Wang, Yu-Ling; Kuo, Je-Hung; Lee, Shao-Chen; Liu, Jai-Shin; Hsieh, Yin-Cheng; Shih, Yu-Tsung; Chen, Chun-Jung; Chiu, Jeng-Jiann; Wu, Wen-Guey

2010-11-26

Cysteine-rich secretory proteins (CRISPs) have been identified as a toxin family in most animal venoms with biological functions mainly associated with the ion channel activity of cysteine-rich domain (CRD). CRISPs also bind to Zn(2+) at their N-terminal pathogenesis-related (PR-1) domain, but their function remains unknown. Interestingly, similar the Zn(2+)-binding site exists in all CRISP family, including those identified in a wide range of organisms. Here, we report that the CRISP from Naja atra (natrin) could induce expression of vascular endothelial cell adhesion molecules, i.e. intercellular adhesion molecule-1, vascular adhesion molecule-1, and E-selectin, to promote monocytic cell adhesion in a heparan sulfate (HS)- and Zn(2+)-dependent manner. Using specific inhibitors and small interfering RNAs, the activation mechanisms are shown to involve both mitogen-activated protein kinases and nuclear factor-κB. Biophysical characterization of natrin by using fluorescence, circular dichroism, and x-ray crystallographic methods further reveals the presence of two Zn(2+)-binding sites for natrin. The strong binding site is located near the putative Ser-His-Glu catalytic triad of the N-terminal domain. The weak binding site remains to be characterized, but it may modulate HS binding by enhancing its interaction with long chain HS. Our results strongly suggest that natrin may serve as an inflammatory modulator that could perturb the wound-healing process of the bitten victim by regulating adhesion molecule expression in endothelial cells. Our finding uncovers a new aspect of the biological role of CRISP family in immune response and is expected to facilitate future development of new therapeutic strategy for the envenomed victims.

Quorum-sensing regulators in Gram-positive bacteria: 'cherchez le peptide'.

PubMed

Monnet, V; Gardan, R

2015-07-01

Gram-positive bacteria can regulate gene expression at the population level via a mechanism known as quorum sensing. Oligopeptides serve as the signaling molecules; they are secreted and then are either detected at the bacterial surface by two-component systems or reinternalized via an oligopeptide transport system. In the latter case, imported peptides interact with cognate regulators (phosphatases or transcriptional regulators) that modulate the expression of target genes. These regulators help control crucial functions such as virulence, persistence, conjugation and competence and have been reported in bacilli, enterococci and streptococci. They form the rapidly growing RRNPP group. In this issue of Molecular Microbiology, Hoover et al. (2015) highlight the group's importance: they have identified a new family of regulators, Tprs (Transcription factor regulated by a Phr peptide), which work with internalized Phr-like peptides. The mechanisms underlying the expression of the genes that encode these internalized peptides are poorly documented. However, Hoover et al. (2015) have provided a new insight: an environmental molecule, glucose, can inhibit expression of the Phr-like peptide gene via catabolic repression. This previously undescribed regulatory pathway, controlling the production of a bacteriocin, might influence Streptococcus pneumonia's fitness in the nasopharynx, where galactose is present. © 2015 John Wiley & Sons Ltd.

PU.1 regulates TCR expression by modulating GATA-3 activity

PubMed Central

Chang, Hua-Chen; Han, Ling; Jabeen, Rukhsana; Carotta, Sebastian; Nutt, Stephen L.; Kaplan, Mark H.

2009-01-01

The Ets transcription factor PU.1 is a master regulator for the development of multiple lineages during hematopoiesis. The expression pattern of PU.1 is dynamically regulated during early T lineage development in the thymus. We previously revealed that PU.1 delineates heterogeneity of effector Th2 populations. In this study, we further define the function of PU.1 on the Th2 phenotype using mice that specifically lack PU.1 in T cells using an lck-Cre transgene with a conditional Sfpi1 allele (Sfpi1lck-/-). While deletion of PU.1 by the lck-Cre transgene does not affect T cell development, Sfpi1lck-/- T cells have a lower activation threshold than wild type T cells. When TCR engagement is limiting, Sfpi1lck-/- T cells cultured in Th2 polarizing conditions secrete higher levels of Th2 cytokines and have greater cytokine homogeneity than wild type cells. We show that PU.1 modulates the levels of TCR expression in CD4+ T cells by regulating the DNA-binding activity of GATA-3 and limiting GATA-3 regulation of TCR gene expression. GATA-3 dependent regulation of TCR expression is also observed in Th1 and Th2 cells. In CD4+ T cells, PU.1 expression segregates into subpopulations of cells that have lower levels of surface TCR, suggesting that PU.1 contributes to the heterogeneity of TCR expression. Thus, we have identified a mechanism whereby increased GATA-3 function in the absence of the antagonizing activity of PU.1 leads to increased TCR expression, a reduced activation threshold and increased homogeneity in Th2 populations. PMID:19801513

Profiling and bioinformatic analysis of circular RNA expression regulated by c-Myc.

PubMed

Gou, Qiheng; Wu, Ke; Zhou, Jian-Kang; Xie, Yuxin; Liu, Lunxu; Peng, Yong

2017-09-22

The c-Myc transcription factor is involved in cell proliferation, cell cycle and apoptosis by activating or repressing transcription of multiple genes. Circular RNAs (circRNAs) are widely expressed non-coding RNAs participating in the regulation of gene expression. Using a high-throughput microarray assay, we showed that Myc regulates the expression of certain circRNAs. A total of 309 up- and 252 down-regulated circRNAs were identified. Among them, randomly selected 8 circRNAs were confirmed by real-time PCR. Subsequently, Myc-binding sites were found to generally exist in the promoter regions of differentially expressed circRNAs. Based on miRNA sponge mechanism, we constructed circRNAs/miRNAs network regulated by Myc, suggesting that circRNAs may widely regulate protein expression through miRNA sponge mechanism. Lastly, we took advantage of Gene Ontology and KEGG analyses to point out that Myc-regulated circRNAs could impact cell proliferation through affecting Ras signaling pathway and pathways in cancer. Our study for the first time demonstrated that Myc transcription factor regulates the expression of circRNAs, adding a novel component of the Myc tumorigenic program and opening a window to investigate the function of certain circRNAs in tumorigenesis.

Macromolecular Crowding Regulates the Gene Expression Profile by Limiting Diffusion

DOE PAGES

Golkaram, Mahdi; Hellander, Stefan; Drawert, Brian; ...

2016-11-28

We seek to elucidate the role of macromolecular crowding in transcription and translation. It is well known that stochasticity in gene expression can lead to differential gene expression and heterogeneity in a cell population. Recent experimental observations by Tan et al. have improved our understanding of the functional role of macromolecular crowding. It can be inferred from their observations that macromolecular crowding can lead to robustness in gene expression, resulting in a more homogeneous cell population. We introduce a spatial stochastic model to provide insight into this process. Our results show that macromolecular crowding reduces noise (as measured by themore » kurtosis of the mRNA distribution) in a cell population by limiting the diffusion of transcription factors (i.e. removing the unstable intermediate states), and that crowding by large molecules reduces noise more efficiently than crowding by small molecules. Finally, our simulation results provide evidence that the local variation in chromatin density as well as the total volume exclusion of the chromatin in the nucleus can induce a homogenous cell population« less

Social isolation mediated anxiety like behavior is associated with enhanced expression and regulation of BDNF in the female mouse brain.

PubMed

Kumari, Anita; Singh, Padmanabh; Baghel, Meghraj Singh; Thakur, M K

2016-05-01

Adverse early life experience is prominent risk factors for numerous psychiatric illnesses, including mood and anxiety disorders. It imposes serious long-term costs on the individual as well as health and social systems. Hence, developing therapies that prevent the long-term consequences of early life stress is of utmost importance, and necessitates a better understanding of the mechanisms by which early life stress triggers long-lasting alterations in gene expression and behavior. Post-weaning isolation rearing of rodents models the behavioral consequences of adverse early life experiences in humans and it is reported to cause anxiety like behavior which is more common in case of females. Therefore, in the present study, we have studied the impact of social isolation of young female mice for 8weeks on the anxiety like behavior and the underlying molecular mechanism. Elevated plus maze and open field test revealed that social isolation caused anxiety like behavior. BDNF, a well-known molecule implicated in the anxiety like behavior, was up-regulated both at the message and protein level in cerebral cortex by social isolation. CREB-1 and CBP, which play a crucial role in BDNF transcription, were up-regulated at mRNA level in cerebral cortex by social isolation. HDAC-2, which negatively regulates BDNF expression, was down-regulated at mRNA and protein level in cerebral cortex by social isolation. Furthermore, BDNF acts in concert with Limk-1, miRNA-132 and miRNA-134 for the regulation of structural and morphological plasticity. Social isolation resulted in up-regulation of Limk-1 mRNA and miRNA-132 expression in the cerebral cortex. MiRNA-134, which inhibits the translation of Limk-1, was decreased in cerebral cortex by social isolation. Taken together, our study suggests that social isolation mediated anxiety like behavior is associated with up-regulation of BDNF expression and concomitant increase in the expression of CBP, CREB-1, Limk-1 and miRNA-132, and decrease

CD28 T-cell costimulatory molecule expression in pemphigus vulgaris.

PubMed

Alecu, M; Ursaciuc, C; Surcel, M; Coman, G; Ciotaru, D; Dobre, M

2009-03-01

CD28 superfamily of immune costimulatory molecules could play an important role in autotolerance control. CD28 costimulation seems to be necessary for regulatory T cell (Treg) activation and successive suppressive activities involved in autoimmunity protection. This study investigates CD28 expression, especially inducible costimulator fraction, on T lymphocytes in pemphigus vulgaris (PV) patients. CD28 expression on T lymphocytes was assessed in 16 PV patients during acute attack. All patients and 10 healthy control subjects were tested for lymphocyte populations, T-cell subpopulations (T-CD4+, T-CD8+), Treg and CD28 expression on T-cell subpopulations. T, B and natural killer cells average values in PV patients were close to the control group values. Compared with control group, PV values showed lower Treg (2.2% compared with 4.7%), slightly decreased CD4+ CD28+ T cells (91% compared with 95%), higher CD4+ CD28- T cells (9% compared with 5%), decreased CD8+ CD28+ T cells (57% and 73%, respectively) and significantly enhanced CD8+ CD28- T cells (43% compared with 27%). These data suggest that Treg-mediated suppressor T-cell effects could be diminished in PV, together with an abnormal or ineffective subsequent helper T-cell suppression. CD28 high expression on helper T cells and low expression on suppressor T cells are arguments for a potential CD28 role in PV autoimmune response mechanism.

Estrogenic gper signaling regulates mir144 expression in cancer cells and cancer-associated fibroblasts (cafs).

PubMed

Vivacqua, Adele; De Marco, Paola; Santolla, Maria Francesca; Cirillo, Francesca; Pellegrino, Michele; Panno, Maria Luisa; Abonante, Sergio; Maggiolini, Marcello

2015-06-30

MicroRNAs (miRNAs) are small non coding RNA molecules that play a crucial role in several pathophysiological conditions, including cancer. The stimulation of hormone-sensitive tumors by estrogens are mediated by estrogen receptor (ER)α and G protein estrogen receptor (GPER). Previous studies have reported that ERα regulates miRNA expression, while this ability of GPER remains to be elucidated. Here, we demonstrate that in SkBr3 breast cancer and HepG2 hepatocarcinoma cells, 17β-estradiol (E2) and the selective GPER ligand G-1 induce miR144 expression through GPER and the involvement of the PI3K/ERK1/2/Elk1 transduction pathway. Moreover, we show that E2 and G-1 down-regulate through miR144 the onco-suppressor Runx1 and increase cell cycle progression. The capability of E2 and G-1 in triggering the induction of miR144 and the down-regulation of Runx1 was also confirmed in cancer-associated fibroblasts (CAFs) that are main components of the tumor microenvironment driving cancer progression. Further confirming these results, Runx1 protein levels were found decreased in tumor xenografts upon G-1 treatment. On the basis of our findings miR144 and Runx1 may be included among the oncotargets of GPER action. Moreover, the present data provide new insights regarding the ability of estrogens to trigger the GPER/miR144/Runx1 transduction pathway toward the stimulation of cancer progression.

Tunable diblock copolypeptide hydrogel depots for local delivery of hydrophobic molecules in healthy and injured central nervous system

PubMed Central

Zhang, Shanshan; Anderson, Mark A.; Ao, Yan; Khakh, Baljit S.; Fan, Jessica; Deming, Timothy J.; Sofroniew, Michael V.

2014-01-01

Many hydrophobic small molecules are available to regulate gene expression and other cellular functions. Locally restricted application of such molecules in the central nervous system (CNS) would be desirable in many experimental and therapeutic settings, but is limited by a lack of innocuous vehicles able to load and easily deliver hydrophobic cargo. Here, we tested the potential for diblock copolypeptide hydrogels (DCH) to serve as such vehicles. In vitro tests on loading and release were conducted with cholesterol and the anti-cancer agent, temozolomide (TMZ). Loading of hydrophobic cargo modified DCH physical properties such as stiffness and viscosity, but these could readily be tuned to desired ranges by modifying DCH concentration, amino acid composition or chain lengths. Different DCH formulations exhibited different loading capacities and different rates of release. For example, comparison of different DCH with increasing alanine contents showed corresponding increases in both cargo loading capacity and time for cargo release. In vivo tests were conducted with tamoxifen, a small synthetic hydrophobic molecule widely used to regulate transgene expression. Tamoxifen released from DCH depots injected into healthy or injured CNS efficiently activated reporter gene expression in a locally restricted manner in transgenic mice. These findings demonstrate the facile and predictable tunability of DCH to achieve a wide range of loading capacities and release profiles of hydrophobic cargos while retaining CNS compatible physical properties. In addition, the findings show that DCH depots injected into the CNS can efficiently deliver small hydrophobic molecules that regulate gene expression in local cells. PMID:24314556

In vivo imaging of endothelial cell adhesion molecule expression after radiosurgery in an animal model of arteriovenous malformation.

PubMed

Raoufi-Rad, Newsha; McRobb, Lucinda S; Lee, Vivienne S; Bervini, David; Grace, Michael; Ukath, Jaysree; Mchattan, Joshua; Sreenivasan, Varun K A; Duong, T T Hong; Zhao, Zhenjun; Stoodley, Marcus A

2017-01-01

Focussed radiosurgery may provide a means of inducing molecular changes on the luminal surface of diseased endothelium to allow targeted delivery of novel therapeutic compounds. We investigated the potential of ionizing radiation to induce surface expression of intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) on endothelial cells (EC) in vitro and in vivo, to assess their suitability as vascular targets in irradiated arteriovenous malformations (AVMs). Cultured brain microvascular EC were irradiated by linear accelerator at single doses of 0, 5, 15 or 25 Gy and expression of ICAM-1 and VCAM-1 measured by qRT-PCR, Western, ELISA and immunocytochemistry. In vivo, near-infrared (NIR) fluorescence optical imaging using Xenolight 750-conjugated ICAM-1 or VCAM-1 antibodies examined luminal biodistribution over 84 days in a rat AVM model after Gamma Knife surgery at a single 15 Gy dose. ICAM-1 and VCAM-1 were minimally expressed on untreated EC in vitro. Doses of 15 and 25 Gy stimulated expression equally; 5 Gy was not different from the unirradiated. In vivo, normal vessels did not bind or retain the fluorescent probes, however binding was significant in AVM vessels. No additive increases in probe binding were found in response to radiosurgery at a dose of 15 Gy. In summary, radiation induces adhesion molecule expression in vitro but elevated baseline levels in AVM vessels precludes further induction in vivo. These molecules may be suitable targets in irradiated vessels without hemodynamic derangement, but not AVMs. These findings demonstrate the importance of using flow-modulated, pre-clinical animal models for validating candidate proteins for vascular targeting in irradiated AVMs.

Hypoxia regulates microRNA expression in the human carotid body

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

Mkrtchian, Souren, E-mail: souren.mkrtchian@ki.se; Lee, Kian Leong, E-mail: csilkl@nus.edu.sg; Kåhlin, Jessica

The carotid body (CB) is the key sensing organ for physiological oxygen levels in the body. Under conditions of low oxygen (hypoxia), the CB plays crucial roles in signaling to the cardiorespiratory center in the medulla oblongata for the restoration of oxygen homeostasis. How hypoxia regulates gene expression in the human CB remains poorly understood. While limited information on transcriptional regulation in animal CBs is available, the identity and impact of important post-transcriptional regulators such as non-coding RNAs, and in particular miRNAs are not known. Here we show using ex vivo experiments that indeed a number of miRNAs are differentiallymore » regulated in surgically removed human CB slices when acute hypoxic conditions were applied. Analysis of the hypoxia-regulated miRNAs shows that they target biological pathways with upregulation of functions related to cell proliferation and immune response and downregulation of cell differentiation and cell death functions. Comparative analysis of the human CB miRNAome with the global miRNA expression patterns of a large number of different human tissues showed that the CB miRNAome had a unique profile which reflects its highly specialized functional status. Nevertheless, the human CB miRNAome is most closely related to the miRNA expression pattern of brain tissues indicating that they may have the most similar developmental origins. - Highlights: • Hypoxia triggers differential expression of many miRNAs in the human carotid body. • This can lead to the upregulation of proliferation and immune response functions. • CB expression profile in the carotid body resembles the miRNA expression pattern in the brain. • miRNAs are involved in the regulation of carotid body functions including oxygen sensing.« less

Chronic epithelial kidney injury molecule-1 expression causes murine kidney fibrosis.

PubMed

Humphreys, Benjamin D; Xu, Fengfeng; Sabbisetti, Venkata; Grgic, Ivica; Movahedi Naini, Said; Wang, Ningning; Chen, Guochun; Xiao, Sheng; Patel, Dhruti; Henderson, Joel M; Ichimura, Takaharu; Mou, Shan; Soeung, Savuth; McMahon, Andrew P; Kuchroo, Vijay K; Bonventre, Joseph V

2013-09-01

Acute kidney injury predisposes patients to the development of both chronic kidney disease and end-stage renal failure, but the molecular details underlying this important clinical association remain obscure. We report that kidney injury molecule-1 (KIM-1), an epithelial phosphatidylserine receptor expressed transiently after acute injury and chronically in fibrotic renal disease, promotes kidney fibrosis. Conditional expression of KIM-1 in renal epithelial cells (Kim1(RECtg)) in the absence of an injury stimulus resulted in focal epithelial vacuolization at birth, but otherwise normal tubule histology and kidney function. By 4 weeks of age, Kim1(RECtg) mice developed spontaneous and progressive interstitial kidney inflammation with fibrosis, leading to renal failure with anemia, proteinuria, hyperphosphatemia, hypertension, cardiac hypertrophy, and death, analogous to progressive kidney disease in humans. Kim1(RECtg) kidneys had elevated expression of proinflammatory monocyte chemotactic protein-1 (MCP-1) at early time points. Heterologous expression of KIM-1 in an immortalized proximal tubule cell line triggered MCP-1 secretion and increased MCP-1-dependent macrophage chemotaxis. In mice expressing a mutant, truncated KIM-1 polypeptide, experimental kidney fibrosis was ameliorated with reduced levels of MCP-1, consistent with a profibrotic role for native KIM-1. Thus, sustained KIM-1 expression promotes kidney fibrosis and provides a link between acute and recurrent injury with progressive chronic kidney disease.

Profiling the dynamic expression of checkpoint molecules on cytokine-induced killer cells from non-small-cell lung cancer patients.

PubMed

Zhang, Lin; Wang, Jian; Wei, Feng; Wang, Kaiyuan; Sun, Qian; Yang, Fan; Jin, Hao; Zheng, Yu; Zhao, Hua; Wang, Limei; Yu, Wenwen; Zhang, Xiying; An, Yang; Yang, Lili; Zhang, Xinwei; Ren, Xiubao

2016-07-12

Immune checkpoints associate with dysfunctional T cells, which have a reduced ability to clear pathogens or cancer cells. T-cell checkpoint blockade may improve patient survival. However, checkpoint molecules on cytokine-induced killer (CIK) cell, a non-specific adoptive immunotherapy, remain unknown. In present study, we detected the dynamic expression of eight major checkpoint molecules (CTLA-4, PD-1, PD-L1, TIM- 3, CEACAM-1, LAG-3, TIGIT and BTLA) on CIK cells from NSCLC patients. The majority of these molecules, except BTLA, were sharply elevated during the early stage of CIK cell culture. Thereafter, PD-1 and TIGIT expressions decreased gradually towards the initial level (day 0). Moreover, CTLA-4 faded away during the later stage of CIK culture. LAG-3 expression decreased but was still significantly higher than the initial level. Of note, PD-L1 remained stably upregulated during CIK culture compared with PD-1, indicating that PD-L1 might act as an inhibitory molecule on CIK cells instead of PD-1. Furthermore, TIM-3 and CEACAM1 were strongly expressed simultaneously during long-term CIK culture and showed a significant and mutually positive correlation. BTLA displayed a distinct pattern, and its expression gradually decreased throughout the CIK culture. These observations suggested that CIK cells might be partly exhausted before clinical transfusion, characterized by the high expression of PD-L1, LAG-3, TIM- 3, and CEACAM-1 and the low expression of TIGIT, BTLA, PD-1, and CTLA-4 compared with initial culture. Our results imply that implementing combined treatment on CIK cells before transfusion via antibodies targeting PD-L1, LAG-3, TIM-3, and CEACAM-1 might improve the efficiency of CIK therapy for NSCLC patients.

SIRT1 inhibits proliferation of pancreatic cancer cells expressing pancreatic adenocarcinoma up-regulated factor (PAUF), a novel oncogene, by suppression of {beta}-catenin

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

Cho, Il-Rae; Koh, Sang Seok; Department of Functional Genomics, University of Science and Technology, Daejeon 305-333

2012-06-29

Highlights: Black-Right-Pointing-Pointer SIRT1 inhibits protein levels of {beta}-catenin and its transcriptional activity. Black-Right-Pointing-Pointer Nuclear localization of SIRT1 is not required for the decrease of {beta}-catenin expression. Black-Right-Pointing-Pointer SIRT1-mediated degradation of {beta}-catenin is not required for GSK-3{beta} and Siah-1 but for proteosome. Black-Right-Pointing-Pointer SIRT1 activation inhibits proliferation of pancreatic cancer cells expressing PAUF. -- Abstract: Because we found in a recent study that pancreatic adenocarcinoma up-regulated factor (PAUF), a novel oncogene, induces a rapid proliferation of pancreatic cells by up-regulation of {beta}-catenin, we postulated that {beta}-catenin might be a target molecule for pancreatic cancer treatment. We thus speculated whether SIRT1, knownmore » to target {beta}-catenin in a colon cancer model, suppresses {beta}-catenin in those pancreatic cancer cells that express PAUF (Panc-PAUF). We further evaluated whether such suppression would lead to inhibition of the proliferation of these cells. The ectopic expression of either SIRT1 or resveratrol (an activator of SIRT1) suppressed levels of {beta}-catenin protein and its transcriptional activity in Panc-PAUF cells. Conversely, suppression of SIRT1 expression by siRNA enhanced {beta}-catenin expression and transcriptional activity. SIRT1 mutant analysis showed that nuclear localization of SIRT1 is not required for reduction of {beta}-catenin. Treatment with MG132, a proteasomal inhibitor, restored {beta}-catenin protein levels, suggesting that SIRT1-mediated degradation of {beta}-catenin requires proteasomal activity. It was reported that inhibition of GSK-3{beta} or Siah-1 stabilizes {beta}-catenin in colon cancer cells, but suppression of GSK-3{beta} or Siah-1 using siRNA in the presence of resveratrol instead diminished {beta}-catenin protein levels in Panc-PAUF cells. This suggests that GSK-3{beta} and Siah-1 are not involved

Regulation of cytokine signaling by B cell antigen receptor and CD40-controlled expression of heparan sulfate proteoglycans.

PubMed

van der Voort, R; Keehnen, R M; Beuling, E A; Spaargaren, M; Pals, S T

2000-10-16

Recently, biochemical, cell biological, and genetic studies have converged to reveal that integral membrane heparan sulfate proteoglycans (HSPGs) are critical regulators of growth and differentiation of epithelial and connective tissues. As a large number of cytokines involved in lymphoid tissue homeostasis or inflammation contain potential HS-binding domains, HSPGs presumably also play important roles in the regulation of the immune response. In this report, we explored the expression, regulation, and function of HSPGs on B lymphocytes. We demonstrate that activation of the B cell antigen receptor (BCR) and/or CD40 induces a strong transient expression of HSPGs on human tonsillar B cells. By means of these HSPGs, the activated B cells can bind hepatocyte growth factor (HGF), a cytokine that regulates integrin-mediated B cell adhesion and migration. This interaction with HGF is highly selective since the HSPGs did not bind the chemokine stromal cell-derived factor (SDF)-1 alpha, even though the affinities of HGF and SDF-1alpha for heparin are similar. On the activated B cells, we observed induction of a specific HSPG isoform of CD44 (CD44-HS), but not of other HSPGs such as syndecans or glypican-1. Interestingly, the expression of CD44-HS on B cells strongly promotes HGF-induced signaling, resulting in an HS-dependent enhanced phosphorylation of Met, the receptor tyrosine kinase for HGF, as well as downstream signaling molecules including Grb2-associated binder 1 (Gab1) and Akt/protein kinase B (PKB). Our results demonstrate that the BCR and CD40 control the expression of HSPGs, specifically CD44-HS. These HSPGs act as functional coreceptors that selectively promote cytokine signaling in B cells, suggesting a dynamic role for HSPGs in antigen-specific B cell differentiation.

Small-molecule inhibitors of toxT expression in Vibrio cholerae.

PubMed

Anthouard, Rebecca; DiRita, Victor J

2013-08-06

Vibrio cholerae, a Gram-negative bacterium, infects humans and causes cholera, a severe disease characterized by vomiting and diarrhea. These symptoms are primarily caused by cholera toxin (CT), whose production by V. cholerae is tightly regulated by the virulence cascade. In this study, we designed and carried out a high-throughput chemical genetic screen to identify inhibitors of the virulence cascade. We identified three compounds, which we named toxtazin A and toxtazin B and B', representing two novel classes of toxT transcription inhibitors. All three compounds reduce production of both CT and the toxin-coregulated pilus (TCP), an important colonization factor. We present evidence that toxtazin A works at the level of the toxT promoter and that toxtazins B and B' work at the level of the tcpP promoter. Treatment with toxtazin B results in a 100-fold reduction in colonization in an infant mouse model of infection, though toxtazin A did not reduce colonization at the concentrations tested. These results add to the growing body of literature indicating that small-molecule inhibitors of virulence genes could be developed to treat infections, as alternatives to antibiotics become increasingly needed. V. cholerae caused more than 580,000 infections worldwide in 2011 alone (WHO, Wkly. Epidemiol. Rec. 87:289-304, 2012). Cholera is treated with an oral rehydration therapy consisting of water, glucose, and electrolytes. However, as V. cholerae is transmitted via contaminated water, treatment can be difficult for communities whose water source is contaminated. In this study, we address the need for new therapeutic approaches by targeting the production of the main virulence factor, cholera toxin (CT). The high-throughput screen presented here led to the identification of two novel classes of inhibitors of the virulence cascade in V. cholerae, toxtazin A and toxtazins B and B'. We demonstrate that (i) small-molecule inhibitors of virulence gene production can be

Transcriptional regulation of mammalian selenoprotein expression

PubMed Central

Stoytcheva, Zoia R.; Berry, Marla J.

2009-01-01

Background Selenoproteins contain the twenty-first amino acid, selenocysteine, and are involved in cellular defenses against oxidative damage, important metabolic and developmental pathways, and responses to environmental challenges. Elucidating the mechanisms regulating selenoprotein expression at the transcriptional level is key to understanding how these mechanisms are called into play to respond to the changing environment. Methods This review summarizes published studies on transcriptional regulation of selenoprotein genes, focused primarily on genes whose encoded protein functions are at least partially understood. This is followed by in silico analysis of predicted regulatory elements in selenoprotein genes, including those in the aforementioned category as well as the genes whose functions are not known. Results Our findings reveal regulatory pathways common to many selenoprotein genes, including several involved in stress-responses. In addition, tissue-specific regulatory factors are implicated in regulating many selenoprotein genes. Conclusions These studies provide new insights into how selenoprotein genes respond to environmental and other challenges, and the roles these proteins play in allowing cells to adapt to these changes. General Significance Elucidating the regulatory mechanisms affecting selenoprotein expression is essential for understanding their roles in human diseases, and for developing diagnostic and potential therapeutic approaches to address dysregulation of members of this gene family. PMID:19465084

β3GnT2 Maintains Adenylyl Cyclase-3 Signaling and Axon Guidance Molecule Expression in the Olfactory Epithelium

PubMed Central

Faden, Ashley A.; Knott, Thomas K.

2011-01-01

In the olfactory epithelium (OE), odorant receptor stimulation generates cAMP signals that function in both odor detection and the regulation of axon guidance molecule expression. The enzyme that synthesizes cAMP, adenylyl cyclase 3 (AC3), is coexpressed in olfactory sensory neurons (OSNs) with poly-N-acetyllactosamine (PLN) oligosaccharides determined by the glycosyltransferase β3GnT2. The loss of either enzyme results in similar defects in olfactory bulb (OB) innervation and OSN survival, suggesting that glycosylation may be important for AC3 function. We show here that AC3 is extensively modified with N-linked PLN, which is essential for AC3 activity and localization. On Western blots, AC3 from the wild-type OE migrates diffusely as a heavily glycosylated 200 kDa band that interacts with the PLN-binding lectin LEA. AC3 from the β3GnT2−/− OE loses these PLN modifications, migrating instead as a 140 kDa glycoprotein. Furthermore, basal and forskolin-stimulated cAMP production is reduced 80–90% in the β3GnT2−/− OE. Although AC3 traffics normally to null OSN cilia, it is absent from axon projections that aberrantly target the OB. The cAMP-dependent guidance receptor neuropilin-1 is also lost from β3GnT2−/− OSNs and axons, while semaphorin-3A ligand expression is upregulated. In addition, kirrel2, a mosaically expressed adhesion molecule that functions in axon sorting, is absent from β3GnT2−/− OB projections. These results demonstrate that PLN glycans are essential in OSNs for proper AC3 localization and function. We propose that the loss of cAMP-dependent guidance cues is also a critical factor in the severe axon guidance defects observed in β3GnT2−/− mice. PMID:21525298

Distinct role of p38 and c-Jun N-terminal kinases in IL-10-dependent and IL-10-independent regulation of the costimulatory molecule B7.2 in lipopolysaccharide-stimulated human monocytic cells.

PubMed

Lim, Wilfred; Ma, Wei; Gee, Katrina; Aucoin, Susan; Nandan, Devki; Diaz-Mitoma, Francisco; Kozlowski, Maya; Kumar, Ashok

2002-02-15

The costimulatory molecule B7.2 (CD86) plays a vital role in immune activation and development of Th responses. The molecular mechanisms by which B7.2 expression is regulated are not understood. We investigated the role of mitogen-activated protein kinases (MAPK) in the regulation of B7.2 expression in LPS-stimulated human monocytic cells. LPS stimulation of human monocytes resulted in the down-regulation of B7.2 expression that could be abrogated by anti-IL-10 Abs. Furthermore, SB202190, a specific inhibitor of p38 MAPK, inhibited LPS-induced IL-10 production and reversed B7.2 down-regulation, suggesting that LPS-induced B7.2 down-regulation may be mediated, at least in part, via regulation of IL-10 production by p38 MAPK. In contrast to human promonocytic THP-1 cells that are refractory to the inhibitory effects of IL-10, LPS stimulation enhanced B7.2 expression. This IL-10-independent B7.2 induction was not influenced by specific inhibitors of either p38 or p42/44 MAPK. To ascertain the role of the c-Jun N-terminal kinase (JNK) MAPK, dexamethasone, an inhibitor of JNK activation, was used, which inhibited LPS-induced B7.2 expression. Transfection of THP-1 cells with a plasmid expressing a dominant-negative stress-activated protein/extracellular signal-regulated kinase kinase 1 significantly reduced LPS-induced B7.2 expression, thus confirming the involvement of JNK. To study the signaling events downstream of JNK activation, we show that dexamethasone did not inhibit LPS-induced NF-kappaB activation in THP-1 cells, suggesting that JNK may not be involved in NF-kappaB activation leading to B7.2 expression. Taken together, our results reveal the distinct involvement of p38 in IL-10-dependent, and JNK in IL-10-independent regulation of B7.2 expression in LPS-stimulated monocytic cells.

Multiple Signaling Pathways Are Involved in the Interleukine-4 Regulated Expression of DC-SIGN in THP-1 Cell Line

PubMed Central

Jin, Changzhong; Wu, Lijuan; Li, Jie; Fang, Meixin; Cheng, Linfang; Wu, Nanping

2012-01-01

Dendritic cell-specific intercellular adhesion molecule-3 grabbing nonintegrin (DC-SIGN) is an important pattern recognition receptor on dendritic cells (DCs), and its expression shows significant cytological and histological specificity, being interleukine-4 (IL-4) dependent. The signaling pathways through which IL-4 regulates expression of DC-SIGN are still unclear. We used phorbol 12-myristate 13-acetate- (PMA-) differentiated THP-1 cells as the in vitro model of monocyte/macrophage cells to study the signaling pathways involved in IL-4-regulated expression of DC-SIGN. We found that a high expression of DC-SIGN could be induced by IL-4 at the levels of mRNA and cell surface protein. Upregulated expression of DC-SIGN was almost completely blocked by the specific inhibitor of ERK pathway, and partly reduced by the specific inhibitors of JAK-STAT and NF-κB pathways. The activation of the three signaling pathways was directly confirmed by testing the phosphorylation of protein kinase within the cytoplasm and nucleus over time. The analysis of cis-acting elements of DC-SIGN promoter showed that the activity of DC-SIGN promoter without Ets-1 transcription factors binding site almost completely disappeared. Our results demonstrated that multiple signaling pathways are involved in IL-4 induced high expression of DC-SIGN on THP-1 cells, in which ERK pathway is the main signaling pathway and mediated by the Ets-1 transcription factors binding site. PMID:22675249

Effect of short peptides on expression of signaling molecules in organotypic pineal cell culture.

PubMed

Khavinson, V Kh; Linkova, N S; Chalisova, N I; Dudkov, A V; Koncevaya, E A

2011-11-01

We demonstrated the influence of short peptides on the expression of signaling molecules in organotypic culture of the pineal gland from 3-month-old rats. Peptides Ala-Glu-Asp-Gly and Lys-Glu-Asp stimulate the expression of proliferative protein Ki-67 in pineal gland culture. These peptides as well as Glu-Asp-Arg and Lys-Glu do not affect the expression of apoptosis marker AIF. The synthesis of transcription factor CGRP by pinealocytes was stimulated only by Ala-Glu-Asp-Gly. Thus, peptide Ala-Glu-Asp-Gly tissue-specifically stimulates proliferative and secretory activities of pinealocytes, which can be used for recovery of pineal gland functions at the molecular level.

Regulation of catalase expression in healthy and cancerous cells.

PubMed

Glorieux, Christophe; Zamocky, Marcel; Sandoval, Juan Marcelo; Verrax, Julien; Calderon, Pedro Buc

2015-10-01

Catalase is an important antioxidant enzyme that dismutates hydrogen peroxide into water and molecular oxygen. The catalase gene has all the characteristics of a housekeeping gene (no TATA box, no initiator element sequence, high GC content in promoter) and a core promoter that is highly conserved among species. We demonstrate in this review that within this core promoter, the presence of DNA binding sites for transcription factors, such as NF-Y and Sp1, plays an essential role in the positive regulation of catalase expression. Additional transcription factors, such as FoxO3a, are also involved in this regulatory process. There is strong evidence that the protein Akt/PKB in the PI3K signaling pathway plays a major role in the expression of catalase by modulating the activity of FoxO3a. Over the past decade, other transcription factors (PPARγ, Oct-1, etc.), as well as genetic, epigenetic, and posttranscriptional processes, have emerged as crucial contributors to the regulation of catalase expression. Altered expression levels of catalase have been reported in cancer tissues compared to their normal counterparts. Deciphering the molecular mechanisms that regulate catalase expression could, therefore, be of crucial importance for the future development of pro-oxidant cancer chemotherapy. Copyright © 2015. Published by Elsevier Inc.

EphA2 signaling is impacted by carcinoembryonic antigen cell adhesion molecule 1-L expression in colorectal cancer liver metastasis in a cell context-dependent manner.

PubMed

Arabzadeh, Azadeh; McGregor, Kevin; Breton, Valérie; Van Der Kraak, Lauren; Akavia, Uri David; Greenwood, Celia M T; Beauchemin, Nicole

2017-11-28

We have shown that carcinoembryonic antigen cell adhesion molecule 1 long isoform (CEACAM1-L) expression in MC38 metastatic colorectal cancer (CRC) cells results in liver metastasis inhibition via CCL2 and STAT3 signaling. But other molecular mechanisms orchestrating CEACAM1-L-mediated metastasis inhibition remain to be defined. We screened a panel of mouse and human CRC cells and evaluated their metastatic outcome after CEACAM1 overexpression or downregulation. An unbiased transcript profiling and a phospho-receptor tyrosine kinase screen comparing MC38 CEACAM1-L-expressing and non-expressing (CT) CRC cells revealed reduced ephrin type-A receptor 2 (EPHA2) expression and activity. An EPHA2-specific inhibitor reduced EPHA2 downstream signaling in CT cells similar to that in CEACAM1-L cells with decreased proliferation and migration. Human CRC patients exhibiting high CEACAM1 in combination with low EPHA2 expression benefited from longer time to first recurrence/metastasis compared to those with high EPHA2 expression. With the added interaction of CEACAM6 , we denoted that CEACAM1 high- and EPHA2 low-expressing patient samples with lower CEACAM6 expression also exhibited a longer time to first recurrence/metastasis. In HT29 human CRC cells, down-regulation of CEACAM1 along with CEA and CEACAM6 up-regulation led to higher metastatic burden. Overall, CEACAM1-L expression in poorly differentiated CRC can inhibit liver metastasis through cell context-dependent EPHA2-mediated signaling. However, CEACAM1's role should be considered in the presence of other CEACAM family members.

Repression of Salmonella enterica phoP Expression by Small Molecules from Physiological Bile

PubMed Central

Antunes, L. Caetano M.; Wang, Melody; Andersen, Sarah K.; Ferreira, Rosana B. R.; Kappelhoff, Reinhild; Han, Jun; Borchers, Christoph H.

2012-01-01

Infection with Salmonella enterica serovar Typhi in humans causes the life-threatening disease typhoid fever. In the laboratory, typhoid fever can be modeled through the inoculation of susceptible mice with Salmonella enterica serovar Typhimurium. Using this murine model, we previously characterized the interactions between Salmonella Typhimurium and host cells in the gallbladder and showed that this pathogen can successfully invade gallbladder epithelial cells and proliferate. Additionally, we showed that Salmonella Typhimurium can use bile phospholipids to grow at high rates. These abilities are likely important for quick colonization of the gallbladder during typhoid fever and further pathogen dissemination through fecal shedding. To further characterize the interactions between Salmonella and the gallbladder environment, we compared the transcriptomes of Salmonella cultures grown in LB broth or physiological murine bile. Our data showed that many genes involved in bacterial central metabolism are affected by bile, with the citric acid cycle being repressed and alternative respiratory systems being activated. Additionally, our study revealed a new aspect of Salmonella interactions with bile through the identification of the global regulator phoP as a bile-responsive gene. Repression of phoP expression could also be achieved using physiological, but not commercial, bovine bile. The biological activity does not involve PhoPQ sensing of a bile component and is not caused by bile acids, the most abundant organic components of bile. Bioactivity-guided purification allowed the identification of a subset of small molecules from bile that can elicit full activity; however, a single compound with phoP inhibitory activity could not be isolated, suggesting that multiple molecules may act in synergy to achieve this effect. Due to the critical role of phoP in Salmonella virulence, further studies in this area will likely reveal aspects of the interaction between Salmonella

MiR-29b inhibits collagen maturation in hepatic stellate cells through down-regulating the expression of HSP47 and lysyl oxidase

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

Zhang, Yifei; Ghazwani, Mohammed; Li, Jiang

Highlights: • Enhanced HSP47 and LOX expression is associated with decreased miR-29b level in liver fibrosis. • miR-29b down-regulates HSP47 and LOX expression. • The suppression of HSP47 and LOX by miR-29b is mediated by putative sites at their 3′-UTRs. • miR-29b inhibits extracellular LOX activity and collagen maturation. - Abstract: Altered expression of miR-29b is implicated in the pathogenesis and progression of liver fibrosis. We and others previously demonstrated that miR-29b down-regulates the expression of several extracellular-matrix (ECM) genes including Col 1A1, Col 3A1 and Elastin via directly targeting their 3′-UTRs. However, whether or not miR-29b plays a rolemore » in the post-translational regulation of ECM biosynthesis has not been reported. Heat shock protein 47 (HSP47) and lysyl oxidase (LOX) are known to be essential for ECM maturation. In this study we have demonstrated that expression of HSP47 and LOX was significantly up-regulated in culture-activated primary rat hepatic stellate cells (HSCs), TGF-β stimulated LX-2 cells and liver tissue of CCl{sub 4}-treated mice, which was accompanied by a decrease of miR-29b level. In addition, over-expression of miR-29b in LX-2 cells resulted in significant inhibition on HSP47 and LOX expression. Mechanistically, miR-29b inhibited the expression of a reporter gene that contains the respective full-length 3′-UTR from HSP47 and LOX gene, and this inhibitory effect was abolished by the deletion of a putative miR-29b targeting sequence from the 3′-UTRs. Transfection of LX-2 cells with miR-29b led to abnormal collagen structure as shown by electron-microscopy, presumably through down-regulation of the expression of molecules involved in ECM maturation including HSP47 and LOX. These results demonstrated that miR-29b is involved in regulating the post-translational processing of ECM and fibril formation.« less

Regulation of MHC class I expression by Foxp3 and its effect on Treg cell function

PubMed Central

Mu, Jie; Tai, Xuguang; Iyer, Shankar S.; Weissman, Jocelyn D.; Singer, Alfred; Singer, Dinah S.

2014-01-01

Expression of MHC class I molecules, which provide immune surveillance against intracellular pathogens, is higher on lymphoid cells than on any other cell types. In T cells, this is a result of activation of class I transcription by the T cell enhanceosome consisting of Runx1, CBFβ and LEF1. We now report that MHC class I transcription in T cells also is enhanced by Foxp3, resulting in higher levels of class I in CD4+CD25+ T regulatory cells than in conventional CD4+CD25− T cells. Interestingly, the effect of Foxp3 regulation of MHC class I transcription is cell-type specific: Foxp3 increases MHC class I expression in T cells but represses it in epithelial tumor cells. In both cell types, Foxp3 targets the upstream IRE and downstream core promoter of the class I gene. Importantly, expression of MHC class I contributes to the function of CD4+CD25+ T regulatory cells by enhancing immune suppression, both in in vitro and in vivo. These findings identify MHC class I genes as direct targets of Foxp3 whose expression augments regulatory T cell function. PMID:24523508

1α,25-dihydroxyvitamin D3 acts via transforming growth factor-β to up-regulate expression of immunosuppressive CD73 on human CD4+ Foxp3- T cells.

PubMed

Mann, Elizabeth H; Chambers, Emma S; Chen, Yin-Huai; Richards, David F; Hawrylowicz, Catherine M

2015-11-01

Vitamin D deficiency is associated with increased incidence and severity of various immune-mediated diseases. Active vitamin D (1α,25-dihydroxyvitamin D3; 1,25(OH)2 D3) up-regulates CD4(+) T-cell expression of the purine ectonucleotidase CD39, a molecule that is associated with the generation of anti-inflammatory adenosine. Here we aimed to investigate the direct impact of 1,25(OH)2 D3 on expression of the downstream ecto-5'-nucleotidase CD73 by human CD4 T cells, and components of the transforming growth factor-β (TGF-β) pathway, which have been implicated in the modulation of CD73 by murine T cells. At 10(-8) to 10(-7) m, 1,25(OH)2 D3 significantly increased expression of CD73 on peripheral human CD4(+) T cells. Although 1,25(OH)2 D3 did not affect the mRNA expression of latent TGF-β1 , 1,25(OH)2 D3 did up-regulate expression of TGF-β-associated molecules [latency-associated peptide (LAP), glycophorin A repetitions predominant (GARP), GP96, neuropilin-1, thrombospondin-1 and αv integrin] which is likely to have contributed to the observed enhancement in TGF-β bioactivity. CD73 was highly co-expressed with LAP and GARP following 1,25(OH)2 D3 treatment, but unexpectedly, each of these cell surface molecules was expressed primarily on CD4(+) Foxp3(-) T cells, rather than CD4(+) Foxp3(+) T cells. Notably, neutralization of TGF-β significantly impaired 1,25(OH)2 D3-mediated induction of CD73. Collectively, we show that 1,25(OH)2 D3 enhances expression of CD73 on CD4(+) Foxp3(-) T cells in a process that is at least partially TGF-β-dependent. These data reveal an additional contributing mechanism by which vitamin D may be protective in immune-mediated disease. © 2015 John Wiley & Sons Ltd.

Zfp206 regulates ES cell gene expression and differentiation.

PubMed

Zhang, Wen; Walker, Emily; Tamplin, Owen J; Rossant, Janet; Stanford, William L; Hughes, Timothy R

2006-01-01

Understanding transcriptional regulation in early developmental stages is fundamental to understanding mammalian development and embryonic stem (ES) cell properties. Expression surveys suggest that the putative SCAN-Zinc finger transcription factor Zfp206 is expressed specifically in ES cells [Zhang,W., Morris,Q.D., Chang,R., Shai,O., Bakowski,M.A., Mitsakakis,N., Mohammad,N., Robinson,M.D., Zirngibl,R., Somogyi,E. et al., (2004) J. Biol., 3, 21; Brandenberger,R., Wei,H., Zhang,S., Lei,S., Murage,J., Fisk,G.J., Li,Y., Xu,C., Fang,R., Guegler,K. et al., (2004) Nat. Biotechnol., 22, 707-716]. Here, we confirm this observation, and we show that ZFP206 expression decreases rapidly upon differentiation of cultured mouse ES cells, and during development of mouse embryos. We find that there are at least six isoforms of the ZFP206 transcript, the longest being predominant. Overexpression and depletion experiments show that Zfp206 promotes formation of undifferentiated ES cell clones, and positively regulates abundance of a very small set of transcripts whose expression is also specific to ES cells and the two- to four-cell stages of preimplantation embryos. This set includes members of the Zscan4, Thoc4, Tcstv1 and eIF-1A gene families, none of which have been functionally characterized in vivo but whose members include apparent transcription factors, RNA-binding proteins and translation factors. Together, these data indicate that Zfp206 is a regulator of ES cell differentiation that controls a set of genes expressed very early in development, most of which themselves appear to be regulators.

Regulation Effects by Programmed Molecules for Transcription-Based Diagnostic Automata towards Therapeutic Use

NASA Astrophysics Data System (ADS)

Hirabayashi, Miki; Ohashi, Hirotada; Kubo, Tai

We have presented experimental analysis on the controllability of our transcription-based diagnostic biomolecular automata by programmed molecules. Focusing on the noninvasive transcriptome diagnosis by salivary mRNAs, we already proposed the novel concept of diagnostic device using DNA computation. This system consists of the main computational element which has a stem shaped promoter region and a pseudo-loop shaped read-only memory region for transcription regulation through the conformation change caused by the recognition of disease-related biomarkers. We utilize the transcription of malachite green aptamer sequence triggered by the target recognition for observation of detection. This algorithm makes it possible to release RNA-aptamer drugs multiply, different from the digestion-based systems by the restriction enzyme which was proposed previously, for the in-vivo use, however, the controllability of aptamer release is not enough at the previous stage. In this paper, we verified the regulation effect on aptamer transcription by programmed molecules in basic conditions towards the developm! ent of therapeutic automata. These results would bring us one step closer to the realization of new intelligent diagnostic and therapeutic automata based on molecular circuits.

Expression analysis of β-glucosidase genes that regulate abscisic acid homeostasis during watermelon (Citrullus lanatus) development and under stress conditions.

PubMed

Li, Qian; Li, Ping; Sun, Liang; Wang, Yanping; Ji, Kai; Sun, Yufei; Dai, Shengjie; Chen, Pei; Duan, Chaorui; Leng, Ping

2012-01-01

The aim of this study was to obtain new insights into the mechanisms that regulate endogenous abscisic acid (ABA) levels by β-glucosidase genes during the development of watermelons (Citrullus lanatus) and under drought stress conditions. In total, five cDNAs from watermelons were cloned by using reverse transcription-PCR (RT-PCR). They included three cDNAs (ClBG1, ClBG2 and ClBG3) homologous to those that encode β-glucosidase l that hydrolyzes the ABA glucose ester (ABA-GE) to release active ABA, ClNCED4, which encodes 9-cis-epoxycarotenoid dioxygenase (NCED), a key enzyme in ABA biosynthesis, and ClCYP707A1, encoding ABA 8'-hydroxylase. A BLAST homology search revealed that the sequences of cDNAs and the deduced amino acids of these genes showed a high degree of homology to comparable molecules of other plant species. During fruit development and ripening, the expressions of ClBG1, ClNCED4 and ClCYP707A1 were relatively low at an early stage, increased rapidly along with fruit ripening, and reached the highest levels at 27 days after full bloom (DAFB) at the harvest stage. This trend was consistent with the accumulation of ABA. The ClBG2 gene on the other hand was highly expressed at 5 DAFB, and then decreased gradually with fruit development. Unlike ClBG1 and ClBG2, the expression of ClBG3 was low at an early stage; its expression peak occurred at 15 DAFB and then declined to the lowest point. When watermelon seedlings were subjected to drought stress, expressions of ClBG1 and ClCYP707A1 were significantly down-regulated, while expressions of ClBG2 and ClNCED4 were up-regulated in the roots, stems and leaves. The expression of ClBG3 was down-regulated in root tissue, but was up-regulated in stems and leaves. In conclusion, endogenous ABA content was modulated by a dynamic balance between biosynthesis and catabolism regulated by ClNCED4, ClCYP707A1 and ClBGs during development and under drought stress condition. It seems likely that β-glucosidase genes are

Regulatory states in the developmental control of gene expression.

PubMed

Peter, Isabelle S

2017-09-01

A growing body of evidence shows that gene expression in multicellular organisms is controlled by the combinatorial function of multiple transcription factors. This indicates that not the individual transcription factors or signaling molecules, but the combination of expressed regulatory molecules, the regulatory state, should be viewed as the functional unit in gene regulation. Here, I discuss the concept of the regulatory state and its proposed role in the genome-wide control of gene expression. Recent analyses of regulatory gene expression in sea urchin embryos have been instrumental for solving the genomic control of cell fate specification in this system. Some of the approaches that were used to determine the expression of regulatory states during sea urchin embryogenesis are reviewed. Significant developmental changes in regulatory state expression leading to the distinct specification of cell fates are regulated by gene regulatory network circuits. How these regulatory state transitions are encoded in the genome is illuminated using the sea urchin endoderm-mesoderms cell fate decision circuit as an example. These observations highlight the importance of considering developmental gene regulation, and the function of individual transcription factors, in the context of regulatory states. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Regulated Expression of Adenoviral Vectors-Based Gene Therapies

PubMed Central

Curtin, James F.; Candolfi, Marianela; Puntel, Mariana; Xiong, Weidong; Muhammad, A. K. M.; Kroeger, Kurt; Mondkar, Sonali; Liu, Chunyan; Bondale, Niyati; Lowenstein, Pedro R.; Castro, Maria G.

2008-01-01

Summary Regulatable promoter systems allow gene expression to be tightly controlled in vivo. This is highly desirable for the development of safe, efficacious adenoviral vectors that can be used to treat human diseases in the clinic. Ideally, regulatable cassettes should have minimal gene expression in the “OFF” state, and expression should quickly reach therapeutic levels in the “ON” state. In addition, the components of regulatable cassettes should be non-toxic at physiological concentrations and should not be immunogenic, especially when treating chronic illness that requires long-lasting gene expression. In this chapter, we will describe in detail protocols to develop and validate first generation (Ad) and high-capacity adenoviral (HC-Ad) vectors that express therapeutic genes under the control of the TetON regulatable system. Our laboratory has successfully used these protocols to regulate the expression of marker genes, immune stimulatory genes, and toxins for cancer gene therapeutics, i.e., glioma that is a deadly form of brain cancer. We have shown that this third generation TetON regulatable system, incorporating a doxycycline (DOX)-sensitive rtTA2S-M2 inducer and tTSKid silencer, is non-toxic, relatively non-immunogenic, and can tightly regulate reporter transgene expression downstream of a TRE promoter from adenoviral vectors in vitro and also in vivo. PMID:18470649

Toll-Like Receptor and Accessory Molecule mRNA Expression in Humans and Mice as Well as in Murine Autoimmunity, Transient Inflammation, and Progressive Fibrosis

PubMed Central

Ramaiah, Santhosh Kumar Vankayala; Günthner, Roman; Lech, Maciej; Anders, Hans-Joachim

2013-01-01

The cell type-, organ-, and species-specific expression of the Toll-like receptors (TLRs) are well described, but little is known about the respective expression profiles of their accessory molecules. We therefore determined the mRNA expression levels of LBP, MD2, CD36, CD14, granulin, HMGB1, LL37, GRP94, UNC93b1, TRIL, PRAT4A, AP3B1, AEP and the respective TLRs in human and mouse solid organs. Humans and mice displayed significant differences between their respective mRNA expression patterns of these factors. In addition, the expression profiles in transient tissue inflammation upon renal ischemia-reperfusion injury, in spleens and kidneys from mice with lupus-like systemic autoimmunity, and in progressive tissue fibrosis upon unilateral ureteral obstruction were studied. Several TLR co-factors were specifically regulated during the different phases of these disease entities, suggesting a functional involvement in the disease process. Thus, the organ- and species-specific expression patterns need to be considered in the design and interpretation of studies related to TLR-mediated innate immunity, which seems to be involved in the tissue injury phase, in the phase of tissue regeneration, and in progressive tissue remodelling. PMID:23803655

Tumour cells down-regulate CCN2 gene expression in co-cultured fibroblasts in a Smad7- and ERK-dependent manner.

PubMed

van Rooyen, Beverley A; Schäfer, Georgia; Leaner, Virna D; Parker, M Iqbal

2013-10-03

Recent studies have revealed that interactions between tumour cells and the surrounding stroma play an important role in facilitating tumour growth and invasion. Stromal fibroblasts produce most of the extracellular matrix components found in the stroma. The aim of this study was to investigate mechanisms involved in tumour cell-mediated regulation of extracellular matrix and adhesion molecules in co-cultured fibroblasts. To this end, microarray analysis was performed on CCD-1068SK human fibroblast cells after direct co-culture with MDA-MB-231 human breast tumour cells. We found that the expression of both connective tissue growth factor (CTGF/CCN2) and type I collagen was negatively regulated in CCD-1068SK fibroblast cells under direct co-culture conditions. Further analysis revealed that Smad7, a known negative regulator of the Smad signalling pathway involved in CCN2 promoter regulation, was increased in directly co-cultured fibroblasts. Inhibition of Smad7 expression in CCD-1068SK fibroblasts resulted in increased CCN2 expression, while Smad7 overexpression had the opposite effect. Silencing CCN2 gene expression in fibroblasts led, in turn, to a decrease in type I collagen mRNA and protein levels. ERK signalling was also shown to be impaired in CCD-1068SK fibroblasts after direct co-culture with MDA-MB-231 tumour cells, with Smad7 overexpression in fibroblasts leading to a similar decrease in ERK activity. These effects were not, however, seen in fibroblasts that were indirectly co-cultured with tumour cells. We therefore conclude that breast cancer cells require close contact with fibroblasts in order to upregulate Smad7 which, in turn, leads to decreased ERK signalling resulting in diminished expression of the stromal proteins CCN2 and type I collagen.

Transcriptional Regulation of CYP2D6 Expression

PubMed Central

Pan, Xian; Ning, Miaoran

2017-01-01

CYP2D6-mediated drug metabolism exhibits large interindividual variability. Although genetic variations in the CYP2D6 gene are well known contributors to the variability, the sources of CYP2D6 variability in individuals of the same genotype remain unexplained. Accumulating data indicate that transcriptional regulation of CYP2D6 may account for part of CYP2D6 variability. Yet, our understanding of factors governing transcriptional regulation of CYP2D6 is limited. Recently, mechanistic studies of increased CYP2D6-mediated drug metabolism in pregnancy revealed two transcription factors, small heterodimer partner (SHP) and Krüppel-like factor 9, as a transcriptional repressor and an activator, respectively, of CYP2D6. Chemicals that increase SHP expression (e.g., retinoids and activators of farnesoid X receptor) were shown to downregulate CYP2D6 expression in the humanized mice as well as in human hepatocytes. This review summarizes the series of studies on the transcriptional regulation of CYP2D6 expression, potentially providing a basis to better understand the large interindividual variability in CYP2D6-mediated drug metabolism. PMID:27698228

Regulation of expression of the ligand for CD40 on T helper lymphocytes.

PubMed

Castle, B E; Kishimoto, K; Stearns, C; Brown, M L; Kehry, M R

1993-08-15

Activated Th cells deliver contact-dependent signals to resting B lymphocytes that initiate and drive B cell proliferation. Recently, a ligand for the B lymphocyte membrane protein, CD40, has been identified that delivers contact-dependent Th cell signals to B cells. A dimeric soluble form of CD40 was produced and used to further characterize the regulation of expression of the CD40 ligand. Expression of the CD40 ligand was rapidly induced after Th lymphocyte activation, and its stability depended upon whether Th cells were activated with soluble or plastic-bound stimuli. Th cells activated with soluble stimuli rapidly turned over cell-surface CD40 ligand whereas Th cells activated with plastic-bound stimuli exhibited more stable CD40 ligand expression for up to 48 h. Removal of activated Th cells from the plastic-bound stimulus resulted in a rapid turnover of CD40 ligand, suggesting that continuous stimulation could maintain CD40 ligand expression. Ligation by soluble CD40 could also stabilize expression of CD40 ligand on the Th cell surface. Both CD40 ligand and IL-2 were transiently synthesized from 1 to 12 h after Th cell activation and had similar kinetics of synthesis. In Con A-activated Th cells newly synthesized CD40 ligand exhibited an initial high turnover (1.5 h t1/2) and after 5 h of Th cell activation became more stable (10-h t1/2). In Th cells activated with plastic-bound anti-CD3, CD40 ligand exhibited a similar biphasic turnover except that the rapid turnover phase began significantly later. This delay could allow more time for newly synthesized CD40 ligand to assemble or associate with other molecules and thus become stabilized on the cell surface. Newly synthesized CD40 ligand in Con A-activated Th cells appeared to not be efficient in delivering Th cell-dependent contact signals to resting B cells, implying the need for assembly or accessory proteins. Regulation of CD40 ligand expression was consistent with all the characteristics of Th cell

Reduced immunohistochemical expression of adhesion molecules in vitiligo skin biopsies.

PubMed

Reichert Faria, Adriane; Jung, Juliana Elizabeth; Silva de Castro, Caio César; de Noronha, Lucia

2017-03-01

Because defects in adhesion impairment seem to be involved in the etiopathogenesis of vitiligo, this study aimed to compare the immunohistochemical expression of several adhesion molecules in the epidermis of vitiligo and non lesional vitiligo skin. Sixty-six specimens of lesional and non lesional skin from 33 volunteers with vitiligo were evaluated by immunohistochemistry using anti-beta-catenin, anti-E-cadherin, anti-laminin, anti-beta1 integrin, anti-collagen IV, anti-ICAM-1 and anti-VCAM-1 antibodies. Biopsies of vitiligo skin demonstrated a significant reduction in the expression of laminin and integrin. The average value of the immunohistochemically positive reaction area of the vitiligo specimens was 3053.2μm 2 , compared with the observed value of 3431.8μm 2 in non vitiligo skin (p=0.003) for laminin. The immuno-positive area was 7174.6μm 2 (vitiligo) and 8966.7μm 2 (non lesional skin) for integrin (p=0.042). A reduction in ICAM-1 and VCAM-1 expression in the basal layer of the epidermis in vitiligo samples was also observed (p=0.001 and p<0.001, respectively). However, no significant differences were observed with respect to the expression of beta-catenin, E-cadherin, and collagen IV between vitiligo and non lesional skin. Our results suggest that an impairment in adhesion exists in vitiligo skin, which is supported by the diminished immunohistochemical expression of laminin, beta1 integrin, ICAM-1 and VCAM-1. Copyright © 2017 Elsevier GmbH. All rights reserved.

Identification of Fibroblast Growth Factor-18 as a Molecule to Protect Adult Articular Cartilage by Gene Expression Profiling*

PubMed Central

Mori, Yoshifumi; Saito, Taku; Chang, Song Ho; Kobayashi, Hiroshi; Ladel, Christoph H.; Guehring, Hans; Chung, Ung-il; Kawaguchi, Hiroshi

2014-01-01

To identify genes that maintain the homeostasis of adult articular cartilage and regenerate its lesions, we initially compared four types of chondrocytes: articular (AA) versus growth plate (AG) cartilage chondrocytes in adult rats, and superficial layer (IS) versus deep layer (ID) chondrocytes of epiphyseal cartilage in infant rats. Microarray analyses revealed that 40 and 186 genes had ≥10-fold higher expression ratios of AA/AG and IS/ID, respectively, and 16 genes showed ≥10-fold of both AA/AG and IS/ID ratios. The results were validated by real-time RT-PCR analysis. Among them, Hoxd1, Fgf18, and Esm1 were expressed more strongly in AA than in IS. Fgf18 was the extracellular and secreted factor that decreased glycosaminoglycan release and depletion from the cartilage, and enhanced proliferation of articular chondrocytes. Fgf18 was strongly expressed in the articular cartilage chondrocytes of adult rats. In a surgical rat osteoarthritis model, a once-weekly injection of recombinant human FGF18 (rhFGF18) given 3 weeks after surgery prevented cartilage degeneration in a dose-dependent manner at 6 and 9 weeks after surgery, with significant effect at 10 μg/week of rhFGF18. As the underlying mechanism, rhFGF18 strongly up-regulated Timp1 expression in the cell and organ cultures, and inhibition of aggrecan release by rhFGF18 was restored by addition of an antibody to Timp1. In conclusion, we have identified Fgf18 as a molecule that protects articular cartilage by gene expression profiling, and the anticatabolic effects may at least partially be mediated by the Timp1 expression. PMID:24577103

Multilevel regulation of gene expression by microRNAs.

PubMed

Makeyev, Eugene V; Maniatis, Tom

2008-03-28

MicroRNAs (miRNAs) are approximately 22-nucleotide-long noncoding RNAs that normally function by suppressing translation and destabilizing messenger RNAs bearing complementary target sequences. Some miRNAs are expressed in a cell- or tissue-specific manner and may contribute to the establishment and/or maintenance of cellular identity. Recent studies indicate that tissue-specific miRNAs may function at multiple hierarchical levels of gene regulatory networks, from targeting hundreds of effector genes incompatible with the differentiated state to controlling the levels of global regulators of transcription and alternative pre-mRNA splicing. This multilevel regulation may allow individual miRNAs to profoundly affect the gene expression program of differentiated cells.

Psmir: a database of potential associations between small molecules and miRNAs.

PubMed

Meng, Fanlin; Wang, Jing; Dai, Enyu; Yang, Feng; Chen, Xiaowen; Wang, Shuyuan; Yu, Xuexin; Liu, Dianming; Jiang, Wei

2016-01-13

miRNAs are key post-transcriptional regulators of many essential biological processes, and their dysregulation has been validated in almost all human cancers. Restoring aberrantly expressed miRNAs might be a novel therapeutics. Recently, many studies have demonstrated that small molecular compounds can affect miRNA expression. Thus, prediction of associations between small molecules and miRNAs is important for investigation of miRNA-targeted drugs. Here, we analyzed 39 miRNA-perturbed gene expression profiles, and then calculated the similarity of transcription responses between miRNA perturbation and drug treatment to predict drug-miRNA associations. At the significance level of 0.05, we obtained 6501 candidate associations between 1295 small molecules and 25 miRNAs, which included 624 FDA approved drugs. Finally, we constructed the Psmir database to store all potential associations and the related materials. In a word, Psmir served as a valuable resource for dissecting the biological significance in small molecules' effects on miRNA expression, which will facilitate developing novel potential therapeutic targets or treatments for human cancers. Psmir is supported by all major browsers, and is freely available at http://www.bio-bigdata.com/Psmir/.

Prostacyclin synthase expression and epigenetic regulation in nonsmall cell lung cancer.

PubMed

Cathcart, Mary-Clare; Gray, Steven G; Baird, Anne-Marie; Boyle, Elaine; Gately, Kathy; Kay, Elaine; Cummins, Robert; Pidgeon, Graham P; O'Byrne, Kenneth J

2011-11-15

Prostacyclin synthase (PGIS) metabolizes prostaglandin H(2), into prostacyclin. This study aimed to determine the expression profile of PGIS in nonsmall cell lung cancer (NSCLC) and examine potential mechanisms involved in PGIS regulation. PGIS expression was examined in human NSCLC and matched controls by reverse transcriptase polymerase chain reaction (RT-PCR), Western analysis, and immunohistochemistry. A 204-patient NSCLC tissue microarray was stained for PGIS and cyclooxygenase 2 (COX2) expression. Staining intensity was correlated with clinical parameters. Epigenetic mechanisms underpinning PGIS promoter expression were examined using RT-PCR, methylation-specific PCR, and chromatin immunoprecipitation analysis. PGIS expression was reduced/absent in human NSCLC protein samples (P < .0001), but not mRNA relative to matched controls. PGIS tissue expression was higher in squamous cell carcinoma (P = .004) and in male patients (P < .05). No significant correlation of PGIS or COX2 expression with overall patient survival was observed, although COX2 was prognostic for short-term (2-year) survival (P < .001). PGIS mRNA expression was regulated by DNA CpG methylation and histone acetylation in NSCLC cell lines, with chromatin remodeling taking place directly at the PGIS gene. PGIS mRNA expression was increased by both demethylation agents and histone deacetylase inhibitors. Protein levels were unaffected by demethylation agents, whereas PGIS protein stability was negatively affected by histone deacetylase inhibitors. PGIS protein expression is reduced in NSCLC, and does not correlate with overall patient survival. PGIS expression is regulated through epigenetic mechanisms. Differences in expression patterns between mRNA and protein levels suggest that PGIS expression and protein stability are regulated post-translationally. PGIS protein stability may have an important therapeutic role in NSCLC. Copyright © 2011 American Cancer Society.

Expression of immune checkpoint molecules in endometrial carcinoma

PubMed Central

LIU, JIA; LIU, YULING; WANG, WULIANG; WANG, CHENYANG; CHE, YANHONG

2015-01-01

The main obstacle in the development of an effective tumor vaccine is the inherent ability of tumors to evade immune responses. Tumors often use common immune mechanisms and regulators to evade the immune system. The present study aimed to analyze the expression levels of indoleamine 2,3-dioxygenase (IDO), programmed death-ligand (PD-L) 1, PD-L2, B7-H4, galectin-1 and galectin-3 in tissue samples from patients with endometrial carcinoma, in order to detect the immunosuppressive environment of endometrial carcinomas. The levels of IDO, PD-L1, PD-L2 and B7-H4 were analyzed by immunohistochemical methods, and the levels of galectin-1 and galectin-3 in tumor lysates were determined using ELISA. PD-L2 was expressed at low levels in the majority of tumor samples. IDO expression was detected in 38, 63 and 43% of primary endometrial carcinoma, recurrent endometrial carcinoma, and metastatic endometrial carcinoma specimens, respectively. Positive expression rates for PD-L1 were 83% in primary endometrial carcinoma, 68% in recurrent endometrial carcinoma, and 100% in metastatic endometrial carcinoma, whereas B7-H4 expression was detected in 100% of both primary endometrial carcinoma and recurrent endometrial carcinoma samples, and in 96% of metastatic endometrial carcinoma specimens. The expression levels of galectin-1 and galectin-3 were not significantly different between the normal and tumor specimens. The results of the present study suggest that the interaction between PD-1/PD-L1 and B7-H4 may be a potential target for immune intervention in the treatment of endometrial carcinoma. Furthermore, the results may provide the basis for immunosuppressant therapy in the treatment of patients with uterine cancer. PMID:26640578

Intercellular adhesion molecule-1 expression by skeletal muscle cells augments myogenesis.

PubMed

Goh, Qingnian; Dearth, Christopher L; Corbett, Jacob T; Pierre, Philippe; Chadee, Deborah N; Pizza, Francis X

2015-02-15

We previously demonstrated that the expression of intercellular adhesion molecule-1 (ICAM-1) by skeletal muscle cells after muscle overload contributes to ensuing regenerative and hypertrophic processes in skeletal muscle. The objective of the present study is to reveal mechanisms through which skeletal muscle cell expression of ICAM-1 augments regenerative and hypertrophic processes of myogenesis. This was accomplished by genetically engineering C2C12 myoblasts to stably express ICAM-1, and by inhibiting the adhesive and signaling functions of ICAM-1 through the use of a neutralizing antibody or cell penetrating peptide, respectively. Expression of ICAM-1 by cultured skeletal muscle cells augmented myoblast-myoblast adhesion, myotube formation, myonuclear number, myotube alignment, myotube-myotube fusion, and myotube size without influencing the ability of myoblasts to proliferate or differentiate. ICAM-1 augmented myotube formation, myonuclear accretion, and myotube alignment through a mechanism involving adhesion-induced activation of ICAM-1 signaling, as these dependent measures were reduced via antibody and peptide inhibition of ICAM-1. The adhesive and signaling functions of ICAM-1 also facilitated myotube hypertrophy through a mechanism involving myotube-myotube fusion, protein synthesis, and Akt/p70s6k signaling. Our findings demonstrate that ICAM-1 expression by skeletal muscle cells augments myogenesis, and establish a novel mechanism through which the inflammatory response facilitates growth processes in skeletal muscle. Copyright © 2014 Elsevier Inc. All rights reserved.

Intercellular Adhesion Molecule-1 Expression by Skeletal Muscle Cells Augments Myogenesis

PubMed Central

Goh, Qingnian; Dearth, Christopher L.; Corbett, Jacob T.; Pierre, Philippe; Chadee, Deborah N.; Pizza, Francis X.

2014-01-01

We previously demonstrated that the expression of intercellular adhesion molecule-1 (ICAM-1) by skeletal muscle cells after muscle overload contributes to ensuing regenerative and hypertrophic processes in skeletal muscle. The objective of the present study is to reveal mechanisms through which skeletal muscle cell expression of ICAM-1 augments regenerative and hypertrophic processes of myogenesis. This was accomplished by genetically engineering C2C12 myoblasts to stably express ICAM-1, and by inhibiting the adhesive and signaling functions of ICAM-1 through the use of a neutralizing antibody or cell penetrating peptide, respectively. Expression of ICAM-1 by cultured skeletal muscle cells augmented myoblast-myoblast adhesion, myotube formation, myonuclear number, myotube alignment, myotube-myotube fusion, and myotube size without influencing the ability of myoblasts to proliferate or differentiate. ICAM-1 augmented myotube formation, myonuclear accretion, and myotube alignment through a mechanism involving adhesion-induced activation of ICAM-1 signaling, as these dependent measures were reduced via antibody and peptide inhibition of ICAM-1. The adhesive and signaling functions of ICAM-1 also facilitated myotube hypertrophy through a mechanism involving myotube-myotube fusion, protein synthesis, and Akt/p70s6k signaling. Our findings demonstrate that ICAM-1 expression by skeletal muscle cells augments myogenesis, and establish a novel mechanism through which the inflammatory response facilitates growth processes in skeletal muscle. PMID:25281303

Down-regulation of increased TRAF6 expression in the peripheral mononuclear cells of patients with primary Sjögren's syndrome by an EBV-EBER1-specific synthetic single-stranded complementary DNA molecule.

PubMed

Sipka, Sándor; Zilahi, Erika; Papp, Gábor; Chen, Ji-Qing; Nagy, Andrea; Hegyi, Katalin; Kónya, József; Zeher, Margit

2017-05-01

We described earlier a simultaneously increased that the increased expression of miRNA-146a/b was accompanied by an increase in the expression of and TRAF6 and a decrease in the expression of IRAK1 genes in the peripheral mononuclear cells (PBMCs) of patients with primary Sjogren's syndrome (pSS) patients. Recently, the expression of EBV encoded. RNA (EBER) was published in the B cells of salivary glands of in pSS. In the present study, we applied an EBV-EBER1 specific synthetic single stranded complementary DNA molecule (EBV-EBER1-cDNA) to test whether any EBER1 related effect exists also in PBMCs of pSS patients. In the PBMCs of pSS patients and healthy controls, we investigated in vitro the effects of a synthetic single stranded EBV-EBER1-cDNA molecule, synthetic double-stranded (ds)RNA polyinosinic-polycytidylic acid [poly (I:C)] and polyadenylic acid potassium salt poly-adenylic acid [poly-(A)] on the expression of TRAF6 gene tested by qRTPCR. The release of interferon -α was detected by ELISA. EBV-EBER1-cDNA resulted in a significant reduction in the expression of TRAF6 in the cells of patients, but in the healthy controls not, whereas the treatments with poly (I:C) and poly-(A) could not reduce the TRAF6 over-expression. No release of EBER1 could be observed in the culture supernatants of patients with pSS. Only the treatment with poly (I:C) resulted in a significant increase of interferon -α release, and only in the heathy controls. No release of EBER1 molecules took place during the culturing of cells. EBV-EBER- cDNA acted functionally on the cells of patients only. These findings give a further evidence of the linkage between EBV and pSS, furthermore, they show the possible role of EBV-EBER1 in the induction of increased TRAF6 expression in the peripheral B cells of Sjögren's patients. © 2017 Asia Pacific League of Associations for Rheumatology and John Wiley & Sons Australia, Ltd.

IL-20 is epigenetically regulated in NSCLC and down regulates the expression of VEGF.

PubMed

Baird, Anne-Marie; Gray, Steven G; O'Byrne, Kenneth J

2011-08-01

IL-20 is a pleiotrophic member of the IL-10 family and plays a role in skin biology and the development of haematopoietic cells. Recently, IL-20 has been demonstrated to have potential anti-angiogenic effects in non-small cell lung cancer (NSCLC) by down regulating COX-2. The expression of IL-20 and its cognate receptors (IL-20RA/B and IL-22R1) was examined in a series of resected fresh frozen NSCLC tumours. Additionally, the expression and epigenetic regulation of this family was examined in normal bronchial epithelial and NSCLC cell lines. Furthermore, the effect of IL-20 on VEGF family members was examined. The expression of IL-20 and its receptors are frequently dysregulated in NSCLC. IL-20RB mRNA was significantly elevated in NSCLC tumours (p<0.01). Protein levels of the receptors, IL-20RB and IL-22R1, were significantly increased (p<0.01) in the tumours of NSCLC patients. IL-20 and its receptors were found to be epigenetically regulated through histone post-translational modifications and DNA CpG residue methylation. In addition, treatment with recombinant IL-20 resulted in decreased expression of the VEGF family members at the mRNA level. This family of genes are dysregulated in NSCLC and are subject to epigenetic regulation. Whilst the anti-angiogenic properties of IL-20 require further clarification, targeting this family via epigenetic means may be a viable therapeutic option in lung cancer treatment. Copyright © 2011 Elsevier Ltd. All rights reserved.

Composition for detection of cell density signal molecule

DOEpatents

Schwarz, Richard I.

2001-01-01

Disclosed herein is a novel proteinaceous cell density signal molecule (CDS), which is secreted by fibroblastic cells in culture, preferably tendon cells, and which provides a means by which the cells self-regulate their proliferation and the expression of differentiated function. CDS, and the antibodies which recognize them, are important for the development of diagnostics and treatments for injuries and diseases involving connective tissues, particularly tendon. Also disclosed are methods of production and use.

Expression and Regulation of Cholecystokinin Receptor in the Chicken's Immune Organs and Cells.

PubMed

El-Kassas, Seham; Odemuyiwa, Solomon; Hajishengallis, George; Connell, Terry D; Nashar, Toufic O

2016-12-01

Cholecystokinin (CCK) is a neuropeptide that affects growth rate in chickens by regulating appetite. CCK peptides exert their function by binding to two identified receptors, CCKAR and CCKBR in the GI tract and the brain, respectively, as well as in other organs. In mammals, CCK/CCKAR interactions affect a number of immunological parameters, including regulation of lymphocytes and functioning of monocytes. Thus, food intake and growth can potentially be altered by infection and the resulting inflammatory immune response. It is uncertain, however, whether chicken express CCKAR in immune organs and cells, and, if so, whether CCKAR expression is regulated by pathogen derived inflammatory stimuli. Herein, we identify expression of CCKAR protein in chicken peripheral blood mononuclear cells (PBMC) including monocytes, and expression of the CCKAR gene in PBMC, thymus, bursa, and spleen, in selected commercial and pure chicken breeds. Further, stimulation with various types of E. coli heat-labile enterotoxins or lipopolysaccharide significantly regulated expression of CCKAR on monocytes in the different breeds. Ligation of CCKAR with antibodies in PBMC induced mobilization of Ca 2+ , indicating that CCKAR is signal competent. Injection with polyinosinic: polycytidylic acid (poly I:C), a synthetic analogue of double stranded viral RNA that binds Toll-Like Receptor-3 (TLR3), also regulated gene expressions of CCKAR and proinflammatory cytokines, in the different breeds. Interestingly, variations in the expression levels of proinflammatory cytokines in the different breeds were highly correlated with CCKAR expression levels. Taken together, these findings indicate that the physiological function of CCKAR in the chicken is tightly regulated in immune organs and cells by external inflammatory stimuli, which in turn regulate growth. This is the first report CCKAR expression in immune organs and cells, in any species, and the initial observation that CCKAR is regulated by

Expression and Regulation of Cholecystokinin Receptor in the Chicken's Immune Organs and Cells

PubMed Central

El-Kassas, Seham; Odemuyiwa, Solomon; Hajishengallis, George; Connell, Terry D; Nashar, Toufic O

2017-01-01

Cholecystokinin (CCK) is a neuropeptide that affects growth rate in chickens by regulating appetite. CCK peptides exert their function by binding to two identified receptors, CCKAR and CCKBR in the GI tract and the brain, respectively, as well as in other organs. In mammals, CCK/CCKAR interactions affect a number of immunological parameters, including regulation of lymphocytes and functioning of monocytes. Thus, food intake and growth can potentially be altered by infection and the resulting inflammatory immune response. It is uncertain, however, whether chicken express CCKAR in immune organs and cells, and, if so, whether CCKAR expression is regulated by pathogen derived inflammatory stimuli. Herein, we identify expression of CCKAR protein in chicken peripheral blood mononuclear cells (PBMC) including monocytes, and expression of the CCKAR gene in PBMC, thymus, bursa, and spleen, in selected commercial and pure chicken breeds. Further, stimulation with various types of E. coli heat-labile enterotoxins or lipopolysaccharide significantly regulated expression of CCKAR on monocytes in the different breeds. Ligation of CCKAR with antibodies in PBMC induced mobilization of Ca2+, indicating that CCKAR is signal competent. Injection with polyinosinic: polycytidylic acid (poly I:C), a synthetic analogue of double stranded viral RNA that binds Toll-Like Receptor-3 (TLR3), also regulated gene expressions of CCKAR and proinflammatory cytokines, in the different breeds. Interestingly, variations in the expression levels of proinflammatory cytokines in the different breeds were highly correlated with CCKAR expression levels. Taken together, these findings indicate that the physiological function of CCKAR in the chicken is tightly regulated in immune organs and cells by external inflammatory stimuli, which in turn regulate growth. This is the first report CCKAR expression in immune organs and cells, in any species, and the initial observation that CCKAR is regulated by

p27Kip1 regulates alpha-synuclein expression

PubMed Central

Gallastegui, Edurne; Domuro, Carla; Serratosa, Joan; Larrieux, Alejandra; Sin, Laura; Martinez, Jonatan; Besson, Arnaud; Morante-Redolat, José Manuel; Orlando, Serena; Aligue, Rosa; Fariñas, Isabel; Pujol, María Jesús; Bachs, Oriol

2018-01-01

Alpha-synuclein (α-SYN) is the main component of anomalous protein aggregates (Lewy bodies) that play a crucial role in several neurodegenerative diseases (synucleinopathies) like Parkinson’s disease and multiple system atrophy. However, the mechanisms involved in its transcriptional regulation are poorly understood. We investigated here the role of the cyclin-dependent kinase (Cdk) inhibitor and transcriptional regulator p27Kip1 (p27) in the regulation of α-SYN expression. We observed that selective deletion of p27 by CRISPR/Cas9 technology in neural cells resulted in increased levels of α-SYN. Knock-down of the member of the same family p21Cip1 (p21) also led to increased α-SYN levels, indicating that p27 and p21 collaborate in the repression of α-SYN transcription. We demonstrated that this repression is mediated by the transcription factor E2F4 and the member of the retinoblastoma protein family p130 and that it is dependent of Cdk activity. Chromatin immunoprecipitation analysis revealed specific binding sites for p27, p21 and E2F4 in the proximal α-SYN gene promoter. Finally, luciferase assays revealed a direct action of p27, p21 and E2F4 in α-SYN gene expression. Our findings reveal for the first time a negative regulatory mechanism of α-SYN expression, suggesting a putative role for cell cycle regulators in the etiology of synucleinopathies. PMID:29662651

IKKβ Regulates VEGF Expression and Is a Potential Therapeutic Target for Ovarian Cancer as an Antiangiogenic Treatment.

PubMed

Kinose, Yasuto; Sawada, Kenjiro; Makino, Hiroshi; Ogura, Tomonori; Mizuno, Tomoko; Suzuki, Noriko; Fujikawa, Tomoyuki; Morii, Eiichi; Nakamura, Koji; Sawada, Ikuko; Toda, Aska; Hashimoto, Kae; Isobe, Aki; Mabuchi, Seiji; Ohta, Tsuyoshi; Itai, Akiko; Morishige, Ken-ichirou; Kurachi, Hirohisa; Kimura, Tadashi

2015-04-01

The prolongation of progression-free survival (PFS) in patients with advanced ovarian cancer by antiangiogenic therapy has been shown in several clinical trials. However, although an anti-VEGF antibody (bevacizumab) is the only option currently available, its efficacy is limited and it is not cost effective for use in all patients. Therefore, the development of a novel antiangiogenic drug, especially composed of small-molecule compounds, could be a powerful armament for ovarian cancer treatment. As NF-κB signaling has the potential to regulate VEGF expression, we determined to identify whether VEGF expression is associated with NF-κB activation and to investigate the possibility of a novel IKKβ inhibitor, IMD-0354 (IMMD Inc.), as an antiangiogenic drug. Tissue microarrays from 94 ovarian cancer tissues were constructed and immunohistochemical analyses performed. We revealed that IKK phosphorylation is an independent prognostic factor (PFS: 26.1 vs. 49.8 months, P = 0.011), and is positively correlated with high VEGF expression. In in vitro analyses, IMD-0354 robustly inhibited adhesive and invasive activities of ovarian cancer cells without impairing cell viabilities. IMD-0354 significantly suppressed VEGF production from cancer cells, which led to the inhibition of angiogenesis. In a xenograft model, the treatment of IMD-0354 significantly inhibited peritoneal dissemination with a marked reduction of intratumoral blood vessel formation followed by the inhibition of VEGF expression from cancer cells. IMD-0354 is a stable small-molecule drug and has already been administered safely to humans in other trials. Antiangiogenic therapy targeting IKKβ is a potential future option to treat ovarian cancer. ©2015 American Association for Cancer Research.

House dust mite induces expression of intercellular adhesion molecule-1 in EoL-1 human eosinophilic leukemic cells.

PubMed

Kwon, Byoung Chul; Sohn, Myung Hyun; Kim, Kyung Won; Kim, Eun Soo; Kim, Kyu-Earn; Shin, Myeong Heon

2007-10-01

The house dust mite (HDM) is considered to be the most common indoor allergen associated with bronchial asthma. In this study, we investigated whether crude extract of the HDM Dermatophagoides farinae could activate human eosinophilic leukemic cells (EoL-1) to induce upregulation of cell-surface adhesion molecules. When EoL-1 cells were incubated with D. farinae extract, expression of intercellular adhesion molecule-1 (ICAM-1) significantly increased on the cell surfaces compared to cells incubated with medium alone. In contrast, surface expression of CD11b and CD49d in EoL-1 cells was not affected by D. farinae extract. In addition, pretreatment of cells with NF-kappaB inhibitor (MG-132) or JNK inhibitor (SP600125) significantly inhibited ICAM-1 expression promoted by HDM extract. However, neither p38 MAP kinase inhibitor nor MEK inhibitor prevented HDM-induced ICAM-1 expression in EoL-1 cells. These results suggest that crude extract of D. farinae induces ICAM-1 expression in EoL-1 cells through signaling pathways involving both NF-kappaB and JNK.

House Dust Mite Induces Expression of Intercellular Adhesion Molecule-1 in EoL-1 Human Eosinophilic Leukemic Cells

PubMed Central

Kwon, Byoung Chul; Sohn, Myung Hyun; Kim, Kyung Won; Kim, Eun Soo; Kim, Kyu-Earn

2007-01-01

The house dust mite (HDM) is considered to be the most common indoor allergen associated with bronchial asthma. In this study, we investigated whether crude extract of the HDM Dermatophagoides farinae could activate human eosinophilic leukemic cells (EoL-1) to induce upregulation of cell-surface adhesion molecules. When EoL-1 cells were incubated with D. farinae extract, expression of intercellular adhesion molecule-1 (ICAM-1) significantly increased on the cell surfaces compared to cells incubated with medium alone. In contrast, surface expression of CD11b and CD49d in EoL-1 cells was not affected by D. farinae extract. In addition, pretreatment of cells with NF-κB inhibitor (MG-132) or JNK inhibitor (SP600125) significantly inhibited ICAM-1 expression promoted by HDM extract. However, neither p38 MAP kinase inhibitor nor MEK inhibitor prevented HDM-induced ICAM-1 expression in EoL-1 cells. These results suggest that crude extract of D. farinae induces ICAM-1 expression in EoL-1 cells through signaling pathways involving both NF-κB and JNK. PMID:17982228

Characteristics of expression and regulation of sirtuins in chicken (Gallus gallus).

PubMed

Ren, Junxiao; Xu, Naiyi; Ma, Zheng; Li, Yanmin; Li, Cuicui; Wang, Yanbin; Tian, Yadong; Liu, Xiaojun; Kang, Xiangtao

2017-05-01

Sirtuins (SIRT1-SIRT7) are a family of NAD + -dependent protein deacetylases that are linked to post-translational regulation of many metabolic processes. There are few reports available for chicken sirtuins (designated cSIRT1-cSIRT7), whose expression and regulation in the liver have yet to be explored. In the present study, we characterized the expression and regulation of sirtuin family members in chicken liver. The results showed that the sirtuin family members in chicken share the same conserved functional SIR2 domains. All the sirtuin family members were expressed extensively in all tissues examined, and the expression levels of cSIRT1, cSIRT2, cSIRT4, cSIRT6, and cSIRT7 in the liver increased significantly with sexual maturity. However, all sirtuin family members were downregulated (P < 0.05) in chicken livers and cultured primary hepatocytes treated with 17β-estradiol. We concluded that the expression levels of some chicken sirtuin family members in the liver were upregulated with sexual maturation, but might not be regulated directly by estrogen. Whereas estrogen could be used as an inhibitor of all sirtuins, both in vivo and in vitro.

Imaging of platelet-derived growth factor receptor β expression in glioblastoma xenografts using affibody molecule 111In-DOTA-Z09591.

PubMed

Tolmachev, Vladimir; Varasteh, Zohreh; Honarvar, Hadis; Hosseinimehr, Seyed Jalal; Eriksson, Olof; Jonasson, Per; Frejd, Fredrik Y; Abrahmsen, Lars; Orlova, Anna

2014-02-01

The overexpression and excessive signaling of platelet-derived growth factor receptor β (PDGFRβ) has been detected in cancers, atherosclerosis, and a variety of fibrotic diseases. Radionuclide in vivo visualization of PDGFRβ expression might help to select PDGFRβ targeting treatment for these diseases. The goal of this study was to evaluate the feasibility of in vivo radionuclide imaging of PDGFRβ expression using an Affibody molecule, a small nonimmunoglobulin affinity protein. The PDGFRβ-binding Z09591 Affibody molecule was site-specifically conjugated with a maleimido derivative of DOTA and labeled with (111)In. Targeting of the PDGFRβ-expressing U-87 MG glioblastoma cell line using (111)In-DOTA-Z09591 was evaluated in vitro and in vivo. DOTA-Z09591 was stably labeled with (111)In with preserved specific binding to PDGFRβ-expressing cells in vitro. The dissociation constant for (111)In-DOTA-Z09591 binding to U-87 MG cells was determined to be 92 ± 10 pM. In mice bearing U-87 MG xenografts, the tumor uptake of (111)In-DOTA-Z09591 was 7.2 ± 2.4 percentage injected dose per gram and the tumor-to-blood ratio was 28 ± 14 at 2 h after injection. In vivo receptor saturation experiments demonstrated that targeting of U-87 MG xenografts in mice was PDGFRβ-specific. U-87 MG xenografts were clearly visualized using small-animal SPECT/CT at 3 h after injection. This study demonstrates the feasibility of in vivo visualization of PDGFRβ-expressing xenografts using an Affibody molecule. Further development of radiolabeled Affibody molecules might provide a useful clinical imaging tool for PDGFRβ expression during various pathologic conditions.

Small-Molecule Sigma1 Modulator Induces Autophagic Degradation of PD-L1.

PubMed

Maher, Christina M; Thomas, Jeffrey D; Haas, Derick A; Longen, Charles G; Oyer, Halley M; Tong, Jane Y; Kim, Felix J

2018-02-01

Emerging evidence suggests that Sigma1 ( SIGMAR1 , also known as sigma-1 receptor) is a unique ligand-regulated integral membrane scaffolding protein that contributes to cellular protein and lipid homeostasis. Previously, we demonstrated that some small-molecule modulators of Sigma1 alter endoplasmic reticulum (ER)-associated protein homeostasis pathways in cancer cells, including the unfolded protein response and autophagy. Programmed death-ligand 1 (PD-L1) is a type I integral membrane glycoprotein that is cotranslationally inserted into the ER and is processed and transported through the secretory pathway. Once at the surface of cancer cells, PD-L1 acts as a T-cell inhibitory checkpoint molecule and suppresses antitumor immunity. Here, we demonstrate that in Sigma1-expressing triple-negative breast and androgen-independent prostate cancer cells, PD-L1 protein levels were suppressed by RNAi knockdown of Sigma1 and by small-molecule inhibition of Sigma1. Sigma1-mediated action was confirmed by pharmacologic competition between Sigma1-selective inhibitor and activator ligands. When administered alone, the Sigma1 inhibitor decreased cell surface PD-L1 expression and suppressed functional interaction of PD-1 and PD-L1 in a coculture of T cells and cancer cells. Conversely, the Sigma1 activator increased PD-L1 cell surface expression, demonstrating the ability to positively and negatively modulate Sigma1 associated PD-L1 processing. We discovered that the Sigma1 inhibitor induced degradation of PD-L1 via autophagy, by a mechanism distinct from bulk macroautophagy or general ER stress-associated autophagy. Finally, the Sigma1 inhibitor suppressed IFNγ-induced PD-L1. Our data demonstrate that small-molecule Sigma1 modulators can be used to regulate PD-L1 in cancer cells and trigger its degradation by selective autophagy. Implications: Sigma1 modulators sequester and eliminate PD-L1 by autophagy, thus preventing functional PD-L1 expression at the cell surface. This

Synergistic Effect of Auto-Activation and Small RNA Regulation on Gene Expression

NASA Astrophysics Data System (ADS)

Xiong, Li-Ping; Ma, Yu-Qiang; Tang, Lei-Han

2010-09-01

Auto-activation and small ribonucleic acid (RNA)-mediated regulation are two important mechanisms in controlling gene expression. We study the synergistic effect of these two regulations on gene expression. It is found that under this combinatorial regulation, gene expression exhibits bistable behaviors at the transition regime, while each of these two regulations, if working solely, only leads to monostability. Within the stochastic framework, the base pairing strength between sRNA and mRNA plays an important role in controlling the transition time between on and off states. The noise strength of protein number in the off state approaches 1 and is smaller than that in the on state. The noise strength also depends on which parameters, the feedback strength or the synthesis rate of small RNA, are tuned in switching the gene expression on and off. Our findings may provide a new insight into gene-regulation mechanism and can be applied in synthetic biology.

Non-conventional expression systems for the production of vaccine proteins and immunotherapeutic molecules

PubMed Central

Legastelois, Isabelle; Buffin, Sophie; Peubez, Isabelle; Mignon, Charlotte; Sodoyer, Régis; Werle, Bettina

2017-01-01

ABSTRACT The increasing demand for recombinant vaccine antigens or immunotherapeutic molecules calls into question the universality of current protein expression systems. Vaccine production can require relatively low amounts of expressed materials, but represents an extremely diverse category consisting of different target antigens with marked structural differences. In contrast, monoclonal antibodies, by definition share key molecular characteristics and require a production system capable of very large outputs, which drives the quest for highly efficient and cost-effective systems. In discussing expression systems, the primary assumption is that a universal production platform for vaccines and immunotherapeutics will unlikely exist. This review provides an overview of the evolution of traditional expression systems, including mammalian cells, yeast and E.coli, but also alternative systems such as other bacteria than E. coli, transgenic animals, insect cells, plants and microalgae, Tetrahymena thermophila, Leishmania tarentolae, filamentous fungi, cell free systems, and the incorporation of non-natural amino acids. PMID:27905833

Reciprocal Regulation of Reactive Oxygen Species and Phospho-CREB Regulates Voltage Gated Calcium Channel Expression during Mycobacterium tuberculosis Infection

PubMed Central

Selvakumar, Arti; Antony, Cecil; Singhal, Jhalak; Tiwari, Brijendra K.; Singh, Yogendra; Natarajan, Krishnamurthy

2014-01-01

Our previous work has demonstrated the roles played by L-type Voltage Gated Calcium Channels (VGCC) in regulating Mycobacterium tuberculosis (M. tb) survival and pathogenesis. Here we decipher mechanisms and pathways engaged by the pathogen to regulate VGCC expression in macrophages. We show that M. tb and its antigen Rv3416 use phospho-CREB (pCREB), Reactive Oxygen Species (ROS), Protein Kinase C (PKC) and Mitogen Activated Protein Kinase (MAPK) to modulate VGCC expression in macrophages. siRNA mediated knockdown of MyD88, IRAK1, IRAK2 or TRAF6 significantly inhibited antigen mediated VGCC expression. Inhibiting Protein Kinase C (PKC) or MEK-ERK1/2 further increased VGCC expression. Interestingly, inhibiting intracellular calcium release upregulated antigen mediated VGCC expression, while inhibiting extracellular calcium influx had no significant effect. siRNA mediated knockdown of transcription factors c-Jun, SOX5 and CREB significantly inhibited Rv3416 mediated VGCC expression. A dynamic reciprocal cross-regulation between ROS and pCREB was observed that in turn governed VGCC expression with ROS playing a limiting role in the process. Further dissection of the mechanisms such as the interplay between ROS and pCREB would improve our understanding of the regulation of VGCC expression during M. tb infection. PMID:24797940

Human T cells engineered to express a programmed death 1/28 costimulatory retargeting molecule display enhanced antitumor activity.

PubMed

Ankri, Chen; Shamalov, Katerina; Horovitz-Fried, Miryam; Mauer, Shmuel; Cohen, Cyrille J

2013-10-15

Adoptive transfer of T cells genetically modified to express cancer-specific receptors can mediate impressive tumor regression in terminally ill patients. However, T cell function and persistence over time could be hampered by the activation of inhibitory costimulatory pathways, such as programmed death 1 (PD1)/programmed death ligand 1, leading to T cell exhaustion and providing tumor cells with an escape mechanism from immunosurveillance. In addition, the lack of positive costimulation at the tumor site can further dampen T cell response. Thus, as T cell genetic engineering has become clinically relevant, we aimed at enhancing T cell antitumor activity by genetically diverting T cell-negative costimulatory signals into positive ones using chimeric costimulatory retargeting molecules and which are composed of the PD1 extracellular domain fused to the signaling domains of positive costimulatory molecules such as CD28 and 4-1BB. After characterizing the optimal PD1 chimera, we designed and optimized a tripartite retroviral vector that enables the simultaneous expression of this chimeric molecule in conjunction with a cancer-specific TCR. Human T cells, transduced to express a PD1/28 chimeric molecule, exhibited enhanced cytokine secretion and upregulation of activation markers upon coculture with tumor cells. These engineered cells also proliferated better compared with control cells. Finally, we tested the function of these cells in two xenograft models of human melanoma tumors and show that PD1/28-engineered human T cells demonstrated superior antitumor function. Overall, we propose that engineering T cells with a costimulatory retargeting molecule can enhance their function, which bears important implications for the improvement of T cell immunotherapy.

Renoprotective effects of berberine and its potential effect on the expression of β-arrestins and intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 in streptozocin-diabetic nephropathy rats.

PubMed

Tang, Li-Qin; Ni, Wei-Jian; Cai, Ming; Ding, Hai-Hua; Liu, Sheng; Zhang, Shan-Tang

2016-09-01

Berberine has been shown to exert protective effects against diabetic nephropathy (DN), but the mechanisms involved have not been fully characterized. The aim of the present study was to explore the effects of berberine on the expression of β-arrestins, intercellular cell adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in DN rat kidneys and investigate the underlying molecular mechanisms. To create the DN model, rats fed a high-fat and high-glucose diet were injected with a single dose of streptozotocin (35 mg/kg, i.p.). Then, DN rats were either treated or not with berberine (50, 100, 200 mg/kg per day, i.g., 8 weeks). Periodic acid-Schiff staining was used to evaluate renal histopathological changes. Renal tissue levels of β-arrestin 1 and β-arrestin 2 were determined by Western blot analysis, whereas immunohistochemistry was used to determine renal ICAM-1 and VCAM-1 levels. Berberine (100, 200 mg/kg) ameliorated the histopathological changes in the diabetic kidney. Western blot analysis revealed significant increases in ICAM-1 and VCAM-1 levels in the kidneys of DN rats, which were reversed by treatment with 100 and 200 mg/kg berberine. In addition, berberine treatment (50, 100, 200 mg/kg) increased diabetic-induced decreases in β-arrestin 1 and β-arrestin 2. Berberine exhibited renoprotective effects in DN rats. The underlying molecular mechanisms may be associated with changes in the levels and regulation of β-arrestin expression, as well as ICAM-1 and VCAM-1 levels in the rat kidney. © 2015 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and Wiley Publishing Asia Pty Ltd.

Up-Regulated Dicer Expression in Patients with Cutaneous Melanoma

PubMed Central

Ma, Zhihai; Swede, Helen; Cassarino, David; Fleming, Elizabeth; Fire, Andrew; Dadras, Soheil S.

2011-01-01

Background MicroRNAs (miRNAs) are small non-coding RNAs (18–24 nucleotides) that have recently been shown to regulate gene expression during cancer progression. Dicer, a central enzyme in the multi-component miRNA biogenesis pathway, is involved in cutting precursor miRNAs to functionally mature forms. Emerging evidence shows that Dicer expression is deregulated in some human malignancies and it correlates with tumor progression, yet this role has not yet been investigated in skin cancers. Methods and Findings Using an anti-human monoclonal antibody against Dicer and immunohistochemistry, we compared the expression of Dicer protein among 404 clinically annotated controls and skin tumors consisting of melanocytic nevi (n = 71), a variety of melanomas (n = 223), carcinomas (n = 73) and sarcomas (n = 12). Results showed a cell-specific up-regulated Dicer in 81% of cutaneous, 80% of acrolentiginous and 96% of metastatic melanoma specimens compared to carcinoma or sarcoma specimens (P<0.0001). The expression of Dicer was significantly higher in melanomas compared to benign melanocytic nevi (P<0.0001). In patients with cutaneous melanomas, Dicer up-regulation was found to be significantly associated with an increased tumor mitotic index (P = 0.04), Breslow's depth of invasion (P = 0.03), nodal metastasis (P = 0.04) and a higher American Joint Committee on Caner (AJCC) clinical stage (P = 0.009). Using western blot analysis, we confirmed the cell-specific up-regulation of Dicer protein in vitro. A pooled-analysis on mRNA profiling in cutaneous tumors showed up-regulation of Dicer at the RNA level in cutaneous melanoma, also showing deregulation of other enzymes that participate in the biogenesis and maturation of canonical miRNAs. Conclusions Increased Dicer expression may be a clinically useful biomarker for patients with cutaneous melanoma. Understanding deregulation of Dicer and its influence on miRNA maturation is needed to predict

Polysialic acid enters the cell nucleus attached to a fragment of the neural cell adhesion molecule NCAM to regulate the circadian rhythm in mouse brain.

PubMed

Westphal, Nina; Kleene, Ralf; Lutz, David; Theis, Thomas; Schachner, Melitta

2016-07-01

In the mammalian nervous system, the neural cell adhesion molecule NCAM is the major carrier of the glycan polymer polysialic acid (PSA) which confers important functions to NCAM's protein backbone. PSA attached to NCAM contributes not only to cell migration, neuritogenesis, synaptic plasticity, and behavior, but also to regulation of the circadian rhythm by yet unknown molecular mechanisms. Here, we show that a PSA-carrying transmembrane NCAM fragment enters the nucleus after stimulation of cultured neurons with surrogate NCAM ligands, a phenomenon that depends on the circadian rhythm. Enhanced nuclear import of the PSA-carrying NCAM fragment is associated with altered expression of clock-related genes, as shown by analysis of cultured neuronal cells deprived of PSA by specific enzymatic removal. In vivo, levels of nuclear PSA in different mouse brain regions depend on the circadian rhythm and clock-related gene expression in suprachiasmatic nucleus and cerebellum is affected by the presence of PSA-carrying NCAM in the cell nucleus. Our conceptually novel observations reveal that PSA attached to a transmembrane proteolytic NCAM fragment containing part of the extracellular domain enters the cell nucleus, where PSA-carrying NCAM contributes to the regulation of clock-related gene expression and of the circadian rhythm. Copyright © 2016 Elsevier Inc. All rights reserved.

Regulators of gene expression as biomarkers for prostate cancer

PubMed Central

Willard, Stacey S; Koochekpour, Shahriar

2012-01-01

Recent technological advancements in gene expression analysis have led to the discovery of a promising new group of prostate cancer (PCa) biomarkers that have the potential to influence diagnosis and the prediction of disease severity. The accumulation of deleterious changes in gene expression is a fundamental mechanism of prostate carcinogenesis. Aberrant gene expression can arise from changes in epigenetic regulation or mutation in the genome affecting either key regulatory elements or gene sequences themselves. At the epigenetic level, a myriad of abnormal histone modifications and changes in DNA methylation are found in PCa patients. In addition, many mutations in the genome have been associated with higher PCa risk. Finally, over- or underexpression of key genes involved in cell cycle regulation, apoptosis, cell adhesion and regulation of transcription has been observed. An interesting group of biomarkers are emerging from these studies which may prove more predictive than the standard prostate specific antigen (PSA) serum test. In this review, we discuss recent results in the field of gene expression analysis in PCa including the most promising biomarkers in the areas of epigenetics, genomics and the transcriptome, some of which are currently under investigation as clinical tests for early detection and better prognostic prediction of PCa. PMID:23226612

Gastrin-releasing peptide induces monocyte adhesion to vascular endothelium by upregulating endothelial adhesion molecules

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

Kim, Mi-Kyoung; Park, Hyun-Joo; Department of Dental Pharmacology, BK21 PLUS Project, School of Dentistry, Pusan National University, Yangsan 626-870

Gastrin-releasing peptide (GRP) is a neuropeptide that plays roles in various pathophysiological conditions including inflammatory diseases in peripheral tissues; however, little is known about whether GRP can directly regulate endothelial inflammatory processes. In this study, we showed that GRP promotes the adhesion of leukocytes to human umbilical vein endothelial cells (HUVECs) and the aortic endothelium. GRP increased the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) by activating nuclear factor-κB (NF-κB) in endothelial cells. In addition, GRP activated extracellular signal-regulated kinase 1/2 (ERK1/2), p38MAPK, and AKT, and the inhibition of these signaling pathways significantly reduced GRP-inducedmore » monocyte adhesion to the endothelium. Overall, our results suggested that GRP may cause endothelial dysfunction, which could be of particular relevance in the development of vascular inflammatory disorders. - Highlights: • GRP induces adhesion of monocytes to vascular endothelium. • GRP increases the expression of endothelial adhesion molecules through the activation of NF-κB. • ERK1/2, p38MAPK, and Akt pathways are involved in the GRP-induced leukocyte adhesiveness to endothelium.« less

Intercellular adhesion molecule-1 expression by skeletal muscle cells augments myogenesis

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

Goh, Qingnian; Dearth, Christopher L.; Corbett, Jacob T.

We previously demonstrated that the expression of intercellular adhesion molecule-1 (ICAM-1) by skeletal muscle cells after muscle overload contributes to ensuing regenerative and hypertrophic processes in skeletal muscle. The objective of the present study is to reveal mechanisms through which skeletal muscle cell expression of ICAM-1 augments regenerative and hypertrophic processes of myogenesis. This was accomplished by genetically engineering C2C12 myoblasts to stably express ICAM-1, and by inhibiting the adhesive and signaling functions of ICAM-1 through the use of a neutralizing antibody or cell penetrating peptide, respectively. Expression of ICAM-1 by cultured skeletal muscle cells augmented myoblast–myoblast adhesion, myotube formation,more » myonuclear number, myotube alignment, myotube–myotube fusion, and myotube size without influencing the ability of myoblasts to proliferate or differentiate. ICAM-1 augmented myotube formation, myonuclear accretion, and myotube alignment through a mechanism involving adhesion-induced activation of ICAM-1 signaling, as these dependent measures were reduced via antibody and peptide inhibition of ICAM-1. The adhesive and signaling functions of ICAM-1 also facilitated myotube hypertrophy through a mechanism involving myotube–myotube fusion, protein synthesis, and Akt/p70s6k signaling. Our findings demonstrate that ICAM-1 expression by skeletal muscle cells augments myogenesis, and establish a novel mechanism through which the inflammatory response facilitates growth processes in skeletal muscle. - Highlights: • We examined mechanisms through which skeletal muscle cell expression of ICAM-1 facilitates events of in vitro myogenesis. • Expression of ICAM-1 by cultured myoblasts did not influence their ability to proliferate or differentiate. • Skeletal muscle cell expression of ICAM-1 augmented myoblast fusion, myotube alignment, myotube–myotube fusion, and myotube size. • ICAM-1 augmented myogenic processes

Emotional Expressivity and Emotion Regulation: Relation to Academic Functioning among Elementary School Children

ERIC Educational Resources Information Center

Kwon, Kyongboon; Hanrahan, Amanda R.; Kupzyk, Kevin A.

2017-01-01

We examined emotional expressivity (i.e., happiness, sadness, and anger) and emotion regulation (regulation of exuberance, sadness, and anger) as they relate to academic functioning (motivation, engagement, and achievement). Also, we tested the premise that emotional expressivity and emotion regulation are indirectly associated with achievement…

The effects of emodin on cell viability, respiratory burst and gene expression of Nrf2-Keap1 signaling molecules in the peripheral blood leukocytes of blunt snout bream (Megalobrama amblycephala).

PubMed

Zhao, Zhenxin; Xie, Jun; Liu, Bo; Ge, Xianping; Song, Changyou; Ren, Mingchun; Zhou, Qunlan; Miao, Linghong; Zhang, Huimin; Shan, Fan; Yang, Zhenfei

2017-03-01

We determined the effects of emodin on the cell viability, respiratory burst activity, mRNA levels of antioxidative enzymes (Cu-Zn SOD, CAT and NOX2), and gene expressions of the Nrf2-Keap1 signaling molecules in the peripheral blood leukocytes of blunt snout bream. Triplicate groups of cultured cells were treated with different concentrations of emodin (0.04-25 μg/ml) for 24 h. Results showed that the emodin caused a dramatic loss in cell viability, and occurred in a dose-dependent manner. Emodin exposure (1-25 μg/ml) were significantly induced the ROS generation compared to the control. The respiratory burst and NADPH oxidase activities were significantly induced at a concentration of 0.20 μg/ml, and inhibited at 25 μg/ml. Besides, mRNA levels of antioxidant enzyme genes were dramatically regulated by emodin exposure for 24 h. During low concentrations of exposure, mRNA levels of Cu-Zn SOD in the cells treated with 0.04, 0.20 μg/ml, CAT, NOX2 and Nrf2 in the cells treated with 1 μg/ml were sharply increased, respectively. Whereas, high concentrations were dramatically down-regulated the gene expressions of CAT in the cells treated with 5, 25 μg/ml and NOX2 in the cells treated with 25 μg/ml. Furthermore, sharp increase in Keap1and Bach1 expression levels were observed a dose-dependent manner. In conclusion, this study demonstrated that emodin could induce antioxidant defenses which were involved in cytotoxic activities, respiratory burst and the transcriptional regulation levels of antioxidant enzymes and Nrf2-Keap1 signaling molecules. Copyright © 2017 Elsevier Ltd. All rights reserved.

Spermidine promotes Bacillus subtilis biofilm formation by activating expression of the matrix regulator slrR.

PubMed

Hobley, Laura; Li, Bin; Wood, Jennifer L; Kim, Sok Ho; Naidoo, Jacinth; Ferreira, Ana Sofia; Khomutov, Maxim; Khomutov, Alexey; Stanley-Wall, Nicola R; Michael, Anthony J

2017-07-21

Ubiquitous polyamine spermidine is not required for normal planktonic growth of Bacillus subtilis but is essential for robust biofilm formation. However, the structural features of spermidine required for B. subtilis biofilm formation are unknown and so are the molecular mechanisms of spermidine-stimulated biofilm development. We report here that in a spermidine-deficient B. subtilis mutant, the structural analogue norspermidine, but not homospermidine, restored biofilm formation. Intracellular biosynthesis of another spermidine analogue, aminopropylcadaverine, from exogenously supplied homoagmatine also restored biofilm formation. The differential ability of C-methylated spermidine analogues to functionally replace spermidine in biofilm formation indicated that the aminopropyl moiety of spermidine is more sensitive to C -methylation, which it is essential for biofilm formation, but that the length and symmetry of the molecule is not critical. Transcriptomic analysis of a spermidine-depleted B. subtilis speD mutant uncovered a nitrogen-, methionine-, and S -adenosylmethionine-sufficiency response, resulting in repression of gene expression related to purine catabolism, methionine and S -adenosylmethionine biosynthesis and methionine salvage, and signs of altered membrane status. Consistent with the spermidine requirement in biofilm formation, single-cell analysis of this mutant indicated reduced expression of the operons for production of the exopolysaccharide and TasA protein biofilm matrix components and SinR antagonist slrR Deletion of sinR or ectopic expression of slrR in the spermidine-deficient Δ speD background restored biofilm formation, indicating that spermidine is required for expression of the biofilm regulator slrR Our results indicate that spermidine functions in biofilm development by activating transcription of the biofilm matrix exopolysaccharide and TasA operons through the regulator slrR . © 2017 by The American Society for Biochemistry and

GATA4 negatively regulates bone sialoprotein expression in osteoblasts.

PubMed

Song, Insun; Jeong, Byung-Chul; Choi, Yong Jun; Chung, Yoon-Sok; Kim, Nacksung

2016-06-01

GATA4 has been reported to act as a negative regulator in osteoblast differentiation by inhibiting the Dlx5 transactivation of Runx2 via the attenuation of the binding ability of Dlx5 to the Runx2 promoter region. Here, we determine the role of GATA4 in the regulation of bone sialoprotein (Bsp) in osteoblasts. We observed that the overexpression of Runx2 or Sox9 induced the Bsp expression in osteoblastic cells. Silencing GATA4 further enhanced the Runx2- and Sox9-mediated Bsp promoter activity, whereas GATA4 overexpression down-regulated Bsp promoter activity mediated by Runx2 and Sox9. GATA4 also interacted with Runx2 and Sox9, by attenuating the binding ability of Runx2 and Sox9 to the Bsp promoter region. Our data suggest that GATA4 acts as a negative regulator of Bsp expression in osteoblasts. [BMB Reports 2016; 49(6): 343-348].

Controlling destiny through chemistry: small-molecule regulators of cell fate.

PubMed

Firestone, Ari J; Chen, James K

2010-01-15

Controlling cell fate is essential for embryonic development, tissue regeneration, and the prevention of human disease. With each cell in the human body sharing a common genome, achieving the appropriate spectrum of stem cells and their differentiated lineages requires the selective activation of developmental signaling pathways, the expression of specific target genes, and the maintenance of these cellular states through epigenetic mechanisms. Small molecules that target these regulatory processes are therefore valuable tools for probing and manipulating the molecular mechanisms by which stem cells self-renew, differentiate, and arise from somatic cell reprogramming. Pharmacological modulators of cell fate could also help remediate human diseases caused by dysregulated cell proliferation or differentiation, heralding a new era in molecular therapeutics.

Expression of Pleiotrophin in the Prostate is Androgen Regulated and it Functions as an Autocrine Regulator of Mesenchyme and Cancer Associated Fibroblasts and as a Paracrine Regulator of Epithelia

PubMed Central

Orr, Brigid; Vanpoucke, Griet; Grace, O Cathal; Smith, Lee; Anderson, Richard A; Riddick, Antony CP; Franco, Omar E; Hayward, Simon W; Thomson, Axel A

2011-01-01

BACKGROUND Androgens and paracrine signaling from mesenchyme/stroma regulate development and disease of the prostate, and gene profiling studies of inductive prostate mesenchyme have identified candidate molecules such as pleiotrophin (Ptn). METHODS Ptn transcripts and protein were localized by in situ and immunohistochemistry and Ptn mRNA was quantitated by Northern blot and qRT-PCR. Ptn function was examined by addition of hPTN protein to rat ventral prostate organ cultures, primary human fetal prostate fibroblasts, prostate cancer associated fibroblasts, and BPH1 epithelia. RESULTS During development, Ptn transcripts and protein were expressed in ventral mesenchymal pad (VMP) and prostatic mesenchyme. Ptn was localized to mesenchyme surrounding ductal epithelial tips undergoing branching morphogenesis, and was located on the surface of epithelia. hPTN protein stimulated branching morphogenesis and stromal and epithelial proliferation, when added to rat VP cultures, and also stimulated growth of fetal human prostate fibroblasts, prostate cancer associated fibroblasts, and BPH1 epithelia. PTN mRNA was enriched in patient-matched normal prostate fibroblasts versus prostate cancer associated fibroblasts. PTN also showed male enriched expression in fetal human male urethra versus female, and between wt male and ARKO male mice. Transcripts for PTN were upregulated by testosterone in fetal human prostate fibroblasts and organ cultures of female rat VMP. Ptn protein was increased by testosterone in organ cultures of female rat VMP and in rat male urethra compared to female. CONCLUSIONS Our data suggest that in the prostate Ptn functions as a regulator of both mesenchymal and epithelial proliferation, and that androgens regulate Ptn levels. Prostate 71:305–317, 2011. © 2010 Wiley-Liss, Inc. PMID:20812209

Induction of HO-1 by carbon monoxide releasing molecule-2 attenuates thrombin-induced COX-2 expression and hypertrophy in primary human cardiomyocytes

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

Chien, Peter Tzu-Yu; Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Kwei-Shan, Tao-Yuan, Taiwan; Lin, Chih-Chung

Carbon monoxide (CO) is one of the cytoprotective byproducts of heme oxygenase (HO)-1 and exerts anti-inflammatory action in various models. However, the detailed mechanisms underlying CO-induced HO-1 expression in primary human cardiomyocytes remain largely unidentified. We used primary left ventricle myocytes as a model and applied CO releasing molecule (CORM)-2 to investigate the relationship of CO and HO-1 expression. We herein used Western blot, real-time PCR, promoter activity and EIA to investigate the role of HO-1 expression protecting against thrombin-mediated responses. We found that thrombin-induced COX-2 expression, PGE{sub 2} release and cardiomyocyte hypertrophy markers (increase in ANF/BNP, α-actin expression andmore » cell surface area) was attenuated by pretreatment with CORM-2 which was partially reversed by hemoglobin (Hb) or ZnPP (an inhibitor of HO-1 activity), suggesting that HO-1/CO system may be of clinical importance to ameliorate heart failure through inhibition of inflammatory responses. CORM-2-induced HO-1 protein expression, mRNA and promoter was attenuated by pretreatment with the inhibitors of Pyk2 (PF431396), PDGFR (AG1296), PI3K (LY294002), Akt (SH-5), p38 (SB202530), JNK1/2 (SP600125), FoxO1 (AS1842856) and Sp1 (mithramycin A). The involvement of these signaling components was further confirmed by transfection with respective siRNAs, consistent with those of pharmacological inhibitors. These results suggested that CORM-2-induced HO-1 expression is mediated through a Pyk2/PDGFR/PI3K/Akt/FoxO1/Sp1-dependent manner and exerts a cytoprotective effect in human cardiomyocytes. - Graphical abstract: In summary, CORM-2 treatment induces Pyk2 transactivated PDGFR, which induces PI3K/Akt/MAPK activation, and then recruits Sp1/Foxo1 transcriptional factors to regulate HO-1 gene expression in primary human cardiomyocytes. - Highlights: • CORM-2 induces HO-1 expression. • Pyk2-dependent PDGFR activates PI3K/Akt/MAPK pathway in CORM-2

Expression of AtWRKY33 encoding a pathogen- or PAMP-responsive WRKY transcription factor is regulated by a composite DNA motif containing W box elements.

PubMed

Lippok, Bernadette; Birkenbihl, Rainer P; Rivory, Gaelle; Brümmer, Janna; Schmelzer, Elmon; Logemann, Elke; Somssich, Imre E

2007-04-01

WRKY transcription factors regulate distinct parts of the plant defense transcriptome. Expression of many WRKY genes themselves is induced by pathogens or pathogen-mimicking molecules. Here, we demonstrate that Arabidopsis WRKY33 responds to various stimuli associated with plant defense as well as to different kinds of phytopathogens. Although rapid pathogen-induced AtWRKY33 expression does not require salicylic acid (SA) signaling, it is dependent on PAD4, a key regulator upstream of SA. Activation of AtWRKY33 is independent of de novo protein synthesis, suggesting that it is at least partly under negative regulatory control. We show that a set of three WRKY-specific cis-acting DNA elements (W boxes) within the AtWRKY33 promoter is required for efficient pathogen- or PAMP-triggered gene activation. This strongly indicates that WRKY transcription factors are major components of the regulatory machinery modulating immediate to early expression of this gene in response to pathogen attack.

The rescue of dentin matrix protein 1 (DMP1)-deficient tooth defects by the transgenic expression of dentin sialophosphoprotein (DSPP) indicates that DSPP is a downstream effector molecule of DMP1 in dentinogenesis.

PubMed

Gibson, Monica Prasad; Zhu, Qinglin; Wang, Suzhen; Liu, Qilin; Liu, Ying; Wang, Xiaofang; Yuan, Baozhi; Ruest, L Bruno; Feng, Jian Q; D'Souza, Rena N; Qin, Chunlin; Lu, Yongbo

2013-03-08

Dentin matrix protein 1 (DMP1) and dentin sialophosphoprotein (DSPP) are essential for the formation of dentin. Previous in vitro studies have indicated that DMP1 might regulate the expression of DSPP during dentinogenesis. To examine whether DMP1 controls dentinogenesis through the regulation of DSPP in vivo, we cross-bred transgenic mice expressing normal DSPP driven by a 3.6-kb rat Col1a1 promoter with Dmp1 KO mice to generate mice expressing the DSPP transgene in the Dmp1 KO genetic background (referred to as "Dmp1 KO/DSPP Tg mice"). We used morphological, histological, and biochemical techniques to characterize the dentin and alveolar bone of Dmp1 KO/DSPP Tg mice compared with Dmp1 KO and wild-type mice. Our analyses showed that the expression of endogenous DSPP was remarkably reduced in the Dmp1 KO mice. Furthermore, the transgenic expression of DSPP rescued the tooth and alveolar bone defects of the Dmp1 KO mice. In addition, our in vitro analyses showed that DMP1 and its 57-kDa C-terminal fragment significantly up-regulated the Dspp promoter activities in a mesenchymal cell line. In contrast, the expression of DMP1 was not altered in the Dspp KO mice. These results provide strong evidence that DSPP is a downstream effector molecule that mediates the roles of DMP1 in dentinogenesis.

Scrutinizing the Expression and Blockade of Inhibitory Molecules Expressed on T Cells from Acute Myeloid Leukemia Patients.

PubMed

Abdolmaleki, Mohsen; Mojtabavi, Nazanin; Zavvar, Mahdi; Vaezi, Mohammad; Noorbakhsh, Farshid; Nicknam, Mohammad Hossein

2018-06-01

T cell exhaustion is an immunosuppressive mechanism which occurs in chronic viral infections, solid tumors and hematologic malignancies. Exhausted T cell has increased the expression of inhibitory receptors, and functional impairment. In this study, we investigated the expression from some of those inhibitory receptors being Programmed death 1 (PD-1), T cell immunoglobulin and mucin domain containing molecules 3 (TIM-3) and CD244 on T cells from Iranian acute myeloid leukemia (AML) patients. Peripheral blood samples were collected from Iranian newly diagnosed AML patients and flow cytometric analysis was accomplished for cell surface expression of PD-1, TIM-3, and CD244 on T lymphocytes. Functionality and proliferation assay were done in the presence of anti-PD-1 and anti-CD244 blocking antibodies. Immunophenotyping of T cells showed a significant increase of PD-1 and CD244 expression on CD4+ and CD8+ T cells of AML patients. Whereas blockade of PD1 and CD244 increased the proliferation of CD4+ and CD8+ T lymphocytes of AML patients but IFN-γ production was not significantly increased. In conclusion, our data indicate that CD4+ and CD8+ T cells from AML patients appeared to be exhausted and blockade of some immune checkpoints can improve the proliferation of those cells.

Epigenetic regulation of serotype expression antagonizes transcriptome dynamics in Paramecium tetraurelia

PubMed Central

Cheaib, Miriam; Dehghani Amirabad, Azim; Nordström, Karl J. V.; Schulz, Marcel H.; Simon, Martin

2015-01-01

Phenotypic variation of a single genotype is achieved by alterations in gene expression patterns. Regulation of such alterations depends on their time scale, where short-time adaptations differ from permanently established gene expression patterns maintained by epigenetic mechanisms. In the ciliate Paramecium, serotypes were described for an epigenetically controlled gene expression pattern of an individual multigene family. Paradoxically, individual serotypes can be triggered in Paramecium by alternating environments but are then stabilized by epigenetic mechanisms, thus raising the question to which extend their expression follows environmental stimuli. To characterize environmental adaptation in the context of epigenetically controlled serotype expression, we used RNA-seq to characterize transcriptomes of serotype pure cultures. The resulting vegetative transcriptome resource is first analysed for genes involved in the adaptive response to the altered environment. Secondly, we identified groups of genes that do not follow the adaptive response but show co-regulation with the epigenetically controlled serotype system, suggesting that their gene expression pattern becomes manifested by similar mechanisms. In our experimental set-up, serotype expression and the entire group of co-regulated genes were stable among environmental changes and only heat-shock genes altered expression of these gene groups. The data suggest that the maintenance of these gene expression patterns in a lineage represents epigenetically controlled robustness counteracting short-time adaptation processes. PMID:26231545

Redox-dependent transcriptional regulation.

PubMed

Liu, Hongjun; Colavitti, Renata; Rovira, Ilsa I; Finkel, Toren

2005-11-11

Reactive oxygen species contribute to the pathogenesis of a number of disparate disorders including tissue inflammation, heart failure, hypertension, and atherosclerosis. In response to oxidative stress, cells activate expression of a number of genes, including those required for the detoxification of reactive molecules as well as for the repair and maintenance of cellular homeostasis. In many cases, these induced genes are regulated by transcription factors whose structure, subcellular localization, or affinity for DNA is directly or indirectly regulated by the level of oxidative stress. This review summarizes the recent progress on how cellular redox status can regulate transcription-factor activity and the implications of this regulation for cardiovascular disease.

Phospholipase C and perfringolysin O from Clostridium perfringens upregulate endothelial cell-leukocyte adherence molecule 1 and intercellular leukocyte adherence molecule 1 expression and induce interleukin-8 synthesis in cultured human umbilical vein endothelial cells.

PubMed Central

Bryant, A E; Stevens, D L

1996-01-01

Clostridium perfringens phospholipase C (PLC) and perfringolysin O (PFO) differentially induced human umbilical vein endothelial cell expression and synthesis of endothelial cell-leukocyte adherence molecule-1 (ELAM-1), intracellular leukocyte adherence molecule-1 (ICAM-1), and interleukin-8 (IL-8). PLC strongly induced expression of ELAM-1, ICAM-1, and IL-8, while PFO stimulated early ICAM-1 expression but did not promote ELAM-1 expression or IL-8 synthesis. PLC caused human umbilical vein endothelial cells to assume a fibroblastoid morphology, whereas PFO, in high concentrations or after prolonged low-dose toxin exposure, caused cell death. The toxin-induced expression of proadhesive and activational proteins and direct cytopathic effects may contribute to the leukostasis, vascular compromise, and capillary leak characteristics of C. perfringens gas gangrene. PMID:8557365

PARP-1 regulates the expression of caspase-11

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

Yoo, Lang; Hong, Seokheon; Shin, Ki Soon

2011-05-13

Highlights: {yields} Knockdown of PARP-1 suppresses the LPS-induced expression of caspase-11. {yields} Knockdown of PARP-1 suppresses the caspase-11 promoter activity following LPS stimulation. {yields} PARP-1 is recruited to the caspase-11 promoter region containing NF-{kappa}B-binding sites following LPS stimulation. {yields} PARP-1 inhibitors cannot suppress the caspase-11 induction. {yields} PARP-1 does not suppress IFN-{gamma}-induced expression of caspase-11. -- Abstract: Poly(ADP-ribose) polymerase-1 (PARP-1) is a multifunctional enzyme that regulates DNA repair, cell death and transcription of inflammatory proteins. In the present study, we present evidence that PARP-1 regulates the expression of caspase-11 following lipopolysaccharide (LPS) stimulation. Knockdown of PARP-1 suppressed the LPS-induced expressionmore » of caspase-11 at both mRNA and protein levels as well as caspase-11 promoter activity. Importantly, PARP-1 was recruited to the caspase-11 promoter region containing predicted nuclear factor (NF)-{kappa}B-binding sites when examined by chromatin immunoprecipitation assay. However, knockdown of PARP-1 did not suppress the expression of caspase-11 induced by interferon-{gamma} that activates signal transducer and activator of transcription 1 but not NF-{kappa}B. PARP-1 enzymatic activity was not required for the caspase-11 upregulation since pharmacological inhibitors of PARP-1 did not suppress the induction of caspase-11. Our results suggest that PARP-1, as a transcriptional cofactor for NF-{kappa}B, regulates the induction of caspase-11 at a transcriptional level.« less

Misfolding of major histocompatibility complex class I molecules in activated T cells allows cis-interactions with receptors and signaling molecules and is associated with tyrosine phosphorylation.

PubMed

Santos, Susana G; Powis, Simon J; Arosa, Fernando A

2004-12-17

Knowledge of the origin and biochemical status of beta(2)-microglobulin-free or misfolded major histocompatibility complex (MHC)-I molecules is essential for understanding their pleiotropic properties. Here we show that in normal human T cells, misfolding of MHC-I molecules is turned on upon activation and cell division and is proportional to the level of proliferation. Immunoprecipitation showed that a number of proteins are associated with MHC-I heavy chains at the surface of activated T cells, including the CD8alphabeta receptor and the chaperone tandem calreticulin/ERp57, associations that rely upon the existence of a pool of HC-10-reactive molecules. Biochemical analysis showed that misfolded MHC-I molecules present at the cell surface are fully glycosylated mature molecules. Importantly, misfolded MHC-I molecules are tyrosine phosphorylated and are associated with kinase activity. In vitro kinase assays followed by reprecipitation indicated that tyrosine phosphorylation of the class I heavy chain is probably mediated by a Src tyrosine kinase because Lck was found associated with HC-10 immunocomplexes. Finally, we show that inhibition of tyrosine phosphorylation by using the Src-family tyrosine kinase inhibitor PP2 resulted in enhanced release of MHC-I heavy chains from the cell surface of activated T cells and a slight down-regulation of cell surface W6/32-reactive molecules. This study provides new insights into the biology of MHC-I molecules and suggests that tyrosine phosphorylation may be involved in the regulation of MHC-I misfolding and expression.

Immunomodulation of classical and non-classical HLA molecules by ionizing radiation.

PubMed

Gallegos, Cristina E; Michelin, Severino; Dubner, Diana; Carosella, Edgardo D

2016-05-01

Radiotherapy has been employed for the treatment of oncological patients for nearly a century, and together with surgery and chemotherapy, radiation oncology constitutes one of the three pillars of cancer therapy. Ionizing radiation has complex effects on neoplastic cells and on tumor microenvironment: beyond its action as a direct cytotoxic agent, tumor irradiation triggers a series of alterations in tumoral cells, which includes the de novo synthesis of particular proteins and the up/down-regulation of cell surface molecules. Additionally, ionizing radiation may induce the release of "danger signals" which may, in turn lead to cellular and molecular responses by the immune system. This immunomodulatory action of ionizing radiation highlights the importance of the combined use (radiotherapy plus immunotherapy) for cancer healing. Major histocompatibility complex antigens (also called Human Leukocyte Antigens, HLA in humans) are one of those molecules whose expression is modulated after irradiation. This review summarizes the modulatory properties of ionizing radiation on the expression of HLA class I (classical and non-classical) and class II molecules, with special emphasis in non-classical HLA-I molecules. Copyright © 2016 Elsevier Inc. All rights reserved.

The small-molecule kinase inhibitor D11 counteracts 17-AAG-mediated up-regulation of HSP70 in brain cancer cells

PubMed Central

Schaefer, Susanne; Svenstrup, Tina H.

2017-01-01

Many types of cancer express high levels of heat shock proteins (HSPs) that are molecular chaperones regulating protein folding and stability ensuring protection of cells from potentially lethal stress. HSPs in cancer cells promote survival, growth and spreading even in situations of growth factors deprivation by associating with oncogenic proteins responsible for cell transformation. Hence, it is not surprising that the identification of potent inhibitors of HSPs, notably HSP90, has been the primary research focus, in recent years. Exposure of cancer cells to HSP90 inhibitors, including 17-AAG, has been shown to cause resistance to chemotherapeutic treatment mostly attributable to induction of the heat shock response and increased cellular levels of pro-survival chaperones. In this study, we show that treatment of glioblastoma cells with 17-AAG leads to HSP90 inhibition indicated by loss of stability of the EGFR client protein, and significant increase in HSP70 expression. Conversely, co-treatment with the small-molecule kinase inhibitor D11 leads to suppression of the heat shock response and inhibition of HSF1 transcriptional activity. Beside HSP70, Western blot and differential mRNA expression analysis reveal that combination treatment causes strong down-regulation of the small chaperone protein HSP27. Finally, we demonstrate that incubation of cells with both agents leads to enhanced cytotoxicity and significantly high levels of LC3-II suggesting autophagy induction. Taken together, results reported here support the notion that including D11 in future treatment regimens based on HSP90 inhibition can potentially overcome acquired resistance induced by the heat shock response in brain cancer cells. PMID:28542269

Adapter molecule Grb2-associated binder 1 is specifically expressed in marginal zone B cells and negatively regulates thymus-independent antigen-2 responses.

PubMed

Itoh, Shousaku; Itoh, Motoyuki; Nishida, Keigo; Yamasaki, Satoru; Yoshida, Yuichi; Narimatsu, Masahiro; Park, Sung Joo; Hibi, Masahiko; Ishihara, Katsuhiko; Hirano, Toshio

2002-05-15

Grb2-associated binder 1 (Gab1) is a member of the Gab/daughter of sevenless family of adapter molecules involved in the signal transduction pathways of a variety of growth factors, cytokines, and Ag receptors. To know the role for Gab1 in hematopoiesis and immune responses in vivo, we analyzed radiation chimeras reconstituted with fetal liver (FL) cells of Gab1(-/-) mice, because Gab1(-/-) mice are lethal to embryos. Transfer of Gab1(-/-) FL cells of 14.5 days post-coitum rescued lethally irradiated mice, indicating that Gab1 is not essential for hematopoiesis. Although mature T and B cell subsets developed normally in the peripheral lymphoid organs, reduction of pre-B cells and increase of myeloid cells in the Gab1(-/-) FL chimeras suggested the regulatory roles for Gab1 in hematopoiesis. The chimera showed augmented IgM and IgG1 production to thymus-independent (TI)-2 Ag, although they showed normal responses for thymus-dependent and TI-1 Ags, indicating its negative role specific to TI-2 response. Gab1(-/-) splenic B cells stimulated with anti-delta-dextran plus IL-4 plus IL-5 showed augmented IgM and IgG1 production in vitro that was corrected by the retrovirus-mediated transfection of the wild-type Gab1 gene, clearly demonstrating the cell-autonomous, negative role of Gab1. Furthermore, we showed that the negative role of Gab1 required its Src homology 2-containing tyrosine phosphatase-2 binding sites. Cell fractionation analysis revealed that nonfollicular B cells were responsible for the augmented Ab production in vitro. Consistent with these results, the Gab1 gene was expressed in marginal zone B cells but not follicular B cells. These results indicated that Gab1 is a unique negative regulator specific for TI-2 responses.

γ-Heptalactone is an endogenously produced quorum-sensing molecule regulating growth and secondary metabolite production by Aspergillus nidulans.

PubMed

Williams, Headley E; Steele, Jonathan C P; Clements, Mark O; Keshavarz, Tajalli

2012-11-01

Microbes monitor their population density through a mechanism termed quorum sensing. It is believed that quorum-sensing molecules diffuse from the microbial cells and circulate in the surrounding environment as a function of cell density. When these molecules reach a threshold concentration, the gene expression of the entire population is altered in a coordinated manner. This work provides evidence that Aspergillus nidulans produces at least one small diffusible molecule during its growth cycle which accumulates at high cell density and alters the organism's behaviour. When added to low-density cell cultures, ethyl acetate extracts from stationary phase culture supernatants of A. nidulans resulted in the abolition of the lag phase, induced an earlier deceleration phase with 16.3 % decrease in the final cell dry weight and resulted in a 37.8 % increase in the expression of ipnA::lacZ reporter gene construct, which was used as a marker for penicillin production compared to non-treated controls. The bioactive molecule present in the stationary phase extract was purified to homogeneity and was identified by liquid chromatography-mass spectrometry and nuclear magnetic resonance spectroscopy to be γ-heptalactone. This study provides the first evidence that A. nidulans produces γ-heptalactone at a high cell density and it can alter the organism's behaviour at a low cell density. γ-Heptalactone hence acts as a quorum-sensing molecule in the producing strain.

Whole blood genome-wide expression profiling and network analysis suggest MELAS master regulators.

PubMed

Mende, Susanne; Royer, Loic; Herr, Alexander; Schmiedel, Janet; Deschauer, Marcus; Klopstock, Thomas; Kostic, Vladimir S; Schroeder, Michael; Reichmann, Heinz; Storch, Alexander

2011-07-01

The heteroplasmic mitochondrial DNA (mtDNA) mutation A3243G causes the mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome as one of the most frequent mitochondrial diseases. The process of reconfiguration of nuclear gene expression profile to accommodate cellular processes to the functional status of mitochondria might be a key to MELAS disease manifestation and could contribute to its diverse phenotypic presentation. To determine master regulatory protein networks and disease-modifying genes in MELAS syndrome. Analyses of whole blood transcriptomes from 10 MELAS patients using a novel strategy by combining classic Affymetrix oligonucleotide microarray profiling with regulatory and protein interaction network analyses. Hierarchical cluster analysis elucidated that the relative abundance of mutant mtDNA molecules is decisive for the nuclear gene expression response. Further analyses confirmed not only transcription factors already known to be involved in mitochondrial diseases (such as TFAM), but also detected the hypoxia-inducible factor 1 complex, nuclear factor Y and cAMP responsive element-binding protein-related transcription factors as novel master regulators for reconfiguration of nuclear gene expression in response to the MELAS mutation. Correlation analyses of gene alterations and clinico-genetic data detected significant correlations between A3243G-induced nuclear gene expression changes and mutant mtDNA load as well as disease characteristics. These potential disease-modifying genes influencing the expression of the MELAS phenotype are mainly related to clusters primarily unrelated to cellular energy metabolism, but important for nucleic acid and protein metabolism, and signal transduction. Our data thus provide a framework to search for new pathogenetic concepts and potential therapeutic approaches to treat the MELAS syndrome.

YY1 positively regulates human UBIAD1 expression

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

Funahashi, Nobuaki, E-mail: nfunahashi@ri.ncgm.go.jp; Department of Metabolic Disorder, Diabetes Research Center, Research Institute, National Center for Global Health and Medicine, Tokyo; Hirota, Yoshihisa

Vitamin K is involved in bone formation and blood coagulation. Natural vitamin K compounds are composed of the plant form phylloquinone (vitamin K{sub 1}) and a series of bacterial menaquionones (MK-n; vitamin K{sub 2}). Menadione (vitamin K{sub 3}) is an artificial vitamin K compound. MK-4 contains 4-isoprenyl as a side group in the 2-methyl-1,4-naphthoquinone common structure and has various bioactivities. UbiA prenyltransferase domain containing 1 (UBIAD1 or TERE1) is the menaquinone-4 biosynthetic enzyme. UBIAD1 transcript expression significantly decreases in patients with prostate carcinoma and overexpressing UBIAD1 inhibits proliferation of a tumour cell line. UBIAD1 mRNA expression is ubiquitous in mousemore » tissues, and higher UBIAD1 mRNA expression levels are detected in the brain, heart, kidneys and pancreas. Several functions of UBIAD1 have been reported; however, regulation of the human UBIAD1 gene has not been elucidated. Here we report cloning and characterisation of the human UBIAD1 promoter. A 5′ rapid amplification of cDNA ends analysis revealed that the main transcriptional start site was 306 nucleotides upstream of the translation initiation codon. Deletion and mutation analyses revealed the functional importance of the YY1 consensus motif. Electrophoretic gel mobility shift and chromatin immunoprecipitation assays demonstrated that YY1 binds the UBIAD1 promoter in vitro and in vivo. In addition, YY1 small interfering RNA decreased endogenous UBIAD1 mRNA expression and UBIAD1 conversion activity. These results suggest that YY1 up-regulates UBIAD1 expression and UBIAD1 conversion activity through the UBIAD1 promoter. - Highlights: • We cloned the human UBIAD1 promoter. • The functional importance of the YY1 motif was identified in the UBIAD1 promoter. • YY1 binds the UBIAD1 promoter in vitro and in vivo. • Knockdown of YY1 significantly decreased UBIAD1 expression. • YY1 up-regulates UBIAD1 conversion activity through the

Hypothalamic AMPK-induced autophagy increases food intake by regulating NPY and POMC expression.

PubMed

Oh, Tae Seok; Cho, Hanchae; Cho, Jae Hyun; Yu, Seong-Woon; Kim, Eun-Kyoung

2016-11-01

Hypothalamic AMP-activated protein kinase (AMPK) plays important roles in the regulation of food intake by altering the expression of orexigenic or anorexigenic neuropeptides. However, little is known about the mechanisms of this regulation. Here, we report that hypothalamic AMPK modulates the expression of NPY (neuropeptide Y), an orexigenic neuropeptide, and POMC (pro-opiomelanocortin-α), an anorexigenic neuropeptide, by regulating autophagic activity in vitro and in vivo. In hypothalamic cell lines subjected to low glucose availability such as 2-deoxy-d-glucose (2DG)-induced glucoprivation or glucose deprivation, autophagy was induced via the activation of AMPK, which regulates ULK1 and MTOR complex 1 followed by increased Npy and decreased Pomc expression. Pharmacological or genetic inhibition of autophagy diminished the effect of AMPK on neuropeptide expression in hypothalamic cell lines. Moreover, AMPK knockdown in the arcuate nucleus of the hypothalamus decreased autophagic activity and changed Npy and Pomc expression, leading to a reduction in food intake and body weight. AMPK knockdown abolished the orexigenic effects of intraperitoneal 2DG injection by decreasing autophagy and changing Npy and Pomc expression in mice fed a high-fat diet. We suggest that the induction of autophagy is a possible mechanism of AMPK-mediated regulation of neuropeptide expression and control of feeding in response to low glucose availability.

Dietary Selenium Supplementation Modulates Growth of Brain Metastatic Tumors and Changes the Expression of Adhesion Molecules in Brain Microvessels.

PubMed

Wrobel, Jagoda K; Wolff, Gretchen; Xiao, Rijin; Power, Ronan F; Toborek, Michal

2016-08-01

Various dietary agents can modulate tumor invasiveness. The current study explored whether selenoglycoproteins (SeGPs) extracted from selenium-enriched yeast affect tumor cell homing and growth in the brain. Mice were fed diets enriched with specific SeGPs (SeGP40 or SeGP65, 1 mg/kg Se each), glycoproteins (GP40 or GP65, 0.2-0.3 mg/kg Se each) or a control diet (0.2-0.3 mg/kg Se) for 12 weeks. Then, murine Lewis lung carcinoma cells were infused into the brain circulation. Analyses were performed at early (48 h) and late stages (3 weeks) post tumor cell infusion. Imaging of tumor progression in the brain revealed that mice fed SeGP65-enriched diet displayed diminished metastatic tumor growth, fewer extravasating tumor cells and smaller metastatic lesions. While administration of tumor cells resulted in a significant upregulation of adhesion molecules in the early stage of tumor progression, overexpression of VCAM-1 (vascular call adhesion molecule-1) and ALCAM (activated leukocyte cell adhesion molecule) messenger RNA (mRNA) was diminished in SeGP65 supplemented mice. Additionally, mice fed SeGP65 showed decreased expression of acetylated NF-κB p65, 48 h post tumor cell infusion. The results indicate that tumor progression in the brain can be modulated by specific SeGPs. Selenium-containing compounds were more effective than their glycoprotein controls, implicating selenium as a potential negative regulator of metastatic process.

The cAMP Response Element Binding protein (CREB) is activated by Insulin-like Growth Factor-1 (IGF-1) and regulates myostatin gene expression in skeletal myoblast

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

Zuloaga, R.; Fuentes, E.N.; Molina, A.

2013-10-18

Highlights: •IGF-1 induces the activation of CREB via IGF-1R/PI3K/PLC signaling pathway. •Calcium dependent signaling pathways regulate myostatin gene expression. •IGF-1 regulates myostatin gene expression via CREB transcription in skeletal myoblast. -- Abstract: Myostatin, a member of the Transforming Growth Factor beta (TGF-β) superfamily, plays an important role as a negative regulator of skeletal muscle growth and differentiation. We have previously reported that IGF-1 induces a transient myostatin mRNA expression, through the activation of the Nuclear Factor of Activated T cells (NFAT) in an IP{sub 3}/calcium-dependent manner. Here we examined the activation of CREB transcription factor as downstream targets of IGF-1more » during myoblast differentiation and its role as a regulator of myostatin gene expression. In cultured skeletal myoblast, IGF-1 induced the phosphorylation and transcriptional activation of CREB via IGF-1 Receptor/Phosphatidylinositol 3-Kinase (PI3K)/Phospholipase C gamma (PLC γ), signaling pathways. Also, IGF-1 induced calcium-dependent molecules such as Calmodulin Kinase II (CaMK II), Extracellular signal-regulated Kinases (ERK), Protein Kinase C (PKC). Additionally, we examined myostatin mRNA levels and myostatin promoter activity in differentiated myoblasts stimulated with IGF-1. We found a significant increase in mRNA contents of myostatin and its reporter activity after treatment with IGF-1. The expression of myostatin in differentiated myoblast was downregulated by the transfection of siRNA–CREB and by pharmacological inhibitors of the signaling pathways involved in CREB activation. By using pharmacological and genetic approaches together these data demonstrate that IGF-1 regulates the myostatin gene expression via CREB transcription factor during muscle cell differentiation.« less

Synergistic and Dose-Controlled Regulation of Cellulase Gene Expression in Penicillium oxalicum.

PubMed

Li, Zhonghai; Yao, Guangshan; Wu, Ruimei; Gao, Liwei; Kan, Qinbiao; Liu, Meng; Yang, Piao; Liu, Guodong; Qin, Yuqi; Song, Xin; Zhong, Yaohua; Fang, Xu; Qu, Yinbo

2015-09-01

Filamentous fungus Penicillium oxalicum produces diverse lignocellulolytic enzymes, which are regulated by the combinations of many transcription factors. Here, a single-gene disruptant library for 470 transcription factors was constructed and systematically screened for cellulase production. Twenty transcription factors (including ClrB, CreA, XlnR, Ace1, AmyR, and 15 unknown proteins) were identified to play putative roles in the activation or repression of cellulase synthesis. Most of these regulators have not been characterized in any fungi before. We identified the ClrB, CreA, XlnR, and AmyR transcription factors as critical dose-dependent regulators of cellulase expression, the core regulons of which were identified by analyzing several transcriptomes and/or secretomes. Synergistic and additive modes of combinatorial control of each cellulase gene by these regulatory factors were achieved, and cellulase expression was fine-tuned in a proper and controlled manner. With one of these targets, the expression of the major intracellular β-glucosidase Bgl2 was found to be dependent on ClrB. The Bgl2-deficient background resulted in a substantial gene activation by ClrB and proved to be closely correlated with the relief of repression mediated by CreA and AmyR during cellulase induction. Our results also signify that probing the synergistic and dose-controlled regulation mechanisms of cellulolytic regulators and using it for reconstruction of expression regulation network (RERN) may be a promising strategy for cellulolytic fungi to develop enzyme hyper-producers. Based on our data, ClrB was identified as focal point for the synergistic activation regulation of cellulase expression by integrating cellulolytic regulators and their target genes, which refined our understanding of transcriptional-regulatory network as a "seesaw model" in which the coordinated regulation of cellulolytic genes is established by counteracting activators and repressors.

Synergistic and Dose-Controlled Regulation of Cellulase Gene Expression in Penicillium oxalicum

PubMed Central

Li, Zhonghai; Yao, Guangshan; Wu, Ruimei; Gao, Liwei; Kan, Qinbiao; Liu, Meng; Yang, Piao; Liu, Guodong; Qin, Yuqi; Song, Xin; Zhong, Yaohua; Fang, Xu; Qu, Yinbo

2015-01-01

Filamentous fungus Penicillium oxalicum produces diverse lignocellulolytic enzymes, which are regulated by the combinations of many transcription factors. Here, a single-gene disruptant library for 470 transcription factors was constructed and systematically screened for cellulase production. Twenty transcription factors (including ClrB, CreA, XlnR, Ace1, AmyR, and 15 unknown proteins) were identified to play putative roles in the activation or repression of cellulase synthesis. Most of these regulators have not been characterized in any fungi before. We identified the ClrB, CreA, XlnR, and AmyR transcription factors as critical dose-dependent regulators of cellulase expression, the core regulons of which were identified by analyzing several transcriptomes and/or secretomes. Synergistic and additive modes of combinatorial control of each cellulase gene by these regulatory factors were achieved, and cellulase expression was fine-tuned in a proper and controlled manner. With one of these targets, the expression of the major intracellular β-glucosidase Bgl2 was found to be dependent on ClrB. The Bgl2-deficient background resulted in a substantial gene activation by ClrB and proved to be closely correlated with the relief of repression mediated by CreA and AmyR during cellulase induction. Our results also signify that probing the synergistic and dose-controlled regulation mechanisms of cellulolytic regulators and using it for reconstruction of expression regulation network (RERN) may be a promising strategy for cellulolytic fungi to develop enzyme hyper-producers. Based on our data, ClrB was identified as focal point for the synergistic activation regulation of cellulase expression by integrating cellulolytic regulators and their target genes, which refined our understanding of transcriptional-regulatory network as a “seesaw model” in which the coordinated regulation of cellulolytic genes is established by counteracting activators and repressors. PMID:26360497

RpoS induces expression of the Vibrio anguillarum quorum-sensing regulator VanT.

PubMed

Weber, Barbara; Croxatto, Antony; Chen, Chang; Milton, Debra L

2008-03-01

In vibrios, regulation of the Vibrio harveyi-like LuxR transcriptional activators occurs post-transcriptionally via small regulatory RNAs (sRNAs) that destabilize the luxR mRNA at a low cell population, eliminating expression of LuxR. Expression of the sRNAs is modulated by the vibrio quorum-sensing phosphorelay systems. However, vanT mRNA, which encodes a LuxR homologue in Vibrio anguillarum, is abundant at low and high cell density, indicating that VanT expression may be regulated via additional mechanisms. In this study, Western analyses showed that VanT was expressed throughout growth with a peak of expression during late exponential growth. VanO induced partial destabilization of vanT mRNA via activation of at least one Qrr sRNA. Interestingly, the sigma factor RpoS significantly stabilized vanT mRNA and induced VanT expression during late exponential growth. This induction was in part due to RpoS repressing expression of Hfq, an RNA chaperone. RpoS is not part of the quorum-sensing regulatory cascade since RpoS did not regulate expression or activity of VanO, and RpoS was not regulated by VanO or VanT. VanT and RpoS were needed for survival following UV irradiation and for pigment and metalloprotease production, suggesting that RpoS works with the quorum-sensing systems to modulate expression of VanT, which regulates survival and stress responses.

Identification of the transcriptional regulators by expression profiling infected with hepatitis B virus.

PubMed

Chai, Xiaoqiang; Han, Yanan; Yang, Jian; Zhao, Xianxian; Liu, Yewang; Hou, Xugang; Tang, Yiheng; Zhao, Shirong; Li, Xiao

2016-02-01

The molecular pathogenesis of infection by hepatitis B virus with human is extremely complex and heterogeneous. To date the molecular information is not clearly defined despite intensive research efforts. Thus, studies aimed at transcription and regulation during virus infection or combined researches of those already known to be beneficial are needed. With the purpose of identifying the transcriptional regulators related to infection of hepatitis B virus in gene level, the gene expression profiles from some normal individuals and hepatitis B patients were analyzed in our study. In this work, the differential expressed genes were selected primarily. The several genes among those were validated in an independent set by qRT-PCR. Then the differentially co-expression analysis was conducted to identify differentially co-expressed links and differential co-expressed genes. Next, the analysis of the regulatory impact factors was performed through mapping the links and regulatory data. In order to give a further insight to these regulators, the co-expression gene modules were identified using a threshold-based hierarchical clustering method. Incidentally, the construction of the regulatory network was generated using the computer software. A total of 137,284 differentially co-expressed links and 780 differential co-expressed genes were identified. These co-expressed genes were significantly enriched inflammatory response. The results of regulatory impact factors revealed several crucial regulators related to hepatocellular carcinoma and other high-rank regulators. Meanwhile, more than one hundred co-expression gene modules were identified using clustering method. In our study, some important transcriptional regulators were identified using a computational method, which may enhance the understanding of disease mechanisms and lead to an improved treatment of hepatitis B. However, further experimental studies are required to confirm these findings. Copyright © 2015 Elsevier

Connexin Channel Permeability to Cytoplasmic Molecules

PubMed Central

Harris, Andrew L.

2007-01-01

Connexin channels are known to be permeable to a variety of cytoplasmic molecules. The first observation of second messenger junctional permeability, made ∼30 years ago, sparked broad interest in gap junction channels as mediators of intercellular molecular signaling. Since then, much has been learned about the diversity of connexin channels with regard to isoform diversity, tissue and developmental distribution, modes of channel regulation, assembly and expression, biochemical modification and permeability, all of which appear to be dynamically regulated. This information has expanded the potential roles of connexin channels in development, physiology and disease, and made their elucidation much more complex - 30 years ago such an orchestra of junctional dynamics was unanticipated. Only recently, however, have investigators been able to directly address, in this more complex framework, the key issue: What specific biological molecules, second messengers and others, are able to permeate the various types of connexin channels, and how well? An important related issue, given the ever-growing list of connexin-related pathologies, is how these permeabilities are altered by disease-causing connexin mutations. Together, many studies show that a variety of cytoplasmic molecules can permeate the different types of connexin channels. A few studies reveal differences in permeation by different molecules through a particular type of connexin channel, and differences in permeation by a particular molecule through different types of connexin channels. This article describes and evaluates the various methods used to obtain these data, presents an annotated compilation of the results, and discusses the findings in the context of what can be inferred about mechanism of selectivity and potential relevance to signaling. The data strongly suggest that highly specific interactions take place between connexin pores and specific biological molecular permeants, and that those

Cold Inducible RNA Binding Protein Is Involved in Chronic Hypoxia Induced Neuron Apoptosis by Down-Regulating HIF-1α Expression and Regulated By microRNA-23a.

PubMed

Chen, Xiaoming; Liu, Xinqin; Li, Bin; Zhang, Qian; Wang, Jiye; Zhang, Wenbin; Luo, Wenjing; Chen, Jingyuan

2017-01-01

Background: Neuron apoptosis mediated by hypoxia inducible factor 1α (HIF-1α) in hippocampus is one of the most important factors accounting for the chronic hypobaric hypoxia induced cognitive impairment. As a neuroprotective molecule that is up-regulated in response to various environmental stress, CIRBP was reported to crosstalk with HIF-1α under cellular stress. However, its function under chronic hypobaric hypoxia remains unknown. Objective: In this study, we tried to identify the role of CIRBP in HIF-1α mediated neuron apoptosis under chronic hypobaric hypoxia and find a possible method to maintain its potential neuroprotective in long-term high altitude environmental exposure. Methods: We established a chronic hypobaric hypoxia rat model as well as a tissue culture model where SH-SY5Y cells were exposed to 1% hypoxia. Based on these models, we measured the expressions of HIF-1α and CIRBP under hypoxia exposure and examined the apoptosis of neurons by TUNEL immunofluorescence staining and western blot analysis of apoptosis related proteins. In addition, by establishing HIF-1α shRNA and pEGFP-CIRBP plasmid transfected cells, we confirmed the role of HIF-1α in chronic hypoxia induced neuron apoptosis and identified the influence of CIRBP over-expression upon HIF-1α and neuron apoptosis in the process of exposure. Furthermore, we measured the expression of the reported hypoxia related miRNAs in both models and the influence of miRNAs' over-expression/knock-down upon CIRBP in the process of HIF-1α mediated neuron apoptosis. Results: HIF-1α expression as well as neuron apoptosis was significantly elevated by chronic hypobaric hypoxia both in vivo and in vitro . CIRBP was induced in the early stage of exposure (3d/7d); however as the exposure was prolonged (21d), CIRBP level of the hypoxia group became significantly lower than that of control. In addition, HIF-1α knockdown significantly decreased neuron apoptosis under hypoxia, suggesting HIF-1α may be

Nuclear factor I-A represses expression of the cell adhesion molecule L1

PubMed Central

2009-01-01

Background The neural cell adhesion molecule L1 plays a crucial role in development and plasticity of the nervous system. Neural cells thus require precise control of L1 expression. Results We identified a full binding site for nuclear factor I (NFI) transcription factors in the regulatory region of the mouse L1 gene. Electrophoretic mobility shift assay (EMSA) showed binding of nuclear factor I-A (NFI-A) to this site. Moreover, for a brain-specific isoform of NFI-A (NFI-A bs), we confirmed the interaction in vivo using chromatin immunoprecipitation (ChIP). Reporter gene assays showed that in neuroblastoma cells, overexpression of NFI-A bs repressed L1 expression threefold. Conclusion Our findings suggest that NFI-A, in particular its brain-specific isoform, represses L1 gene expression, and might act as a second silencer of L1 in addition to the neural restrictive silencer factor (NRSF). PMID:20003413

Regulation of CD93 cell surface expression by protein kinase C isoenzymes.

PubMed

Ikewaki, Nobunao; Kulski, Jerzy K; Inoko, Hidetoshi

2006-01-01

Human CD93, also known as complement protein 1, q subcomponent, receptor (C1qRp), is selectively expressed by cells with a myeloid lineage, endothelial cells, platelets, and microglia and was originally reported to be involved in the complement protein 1, q subcomponent (C1q)-mediated enhancement of phagocytosis. The intracellular molecular events responsible for the regulation of its expression on the cell surface, however, have not been determined. In this study, the effect of protein kinases in the regulation of CD93 expression on the cell surface of a human monocyte-like cell line (U937), a human NK-like cell line (KHYG-1), and a human umbilical vein endothelial cell line (HUV-EC-C) was investigated using four types of protein kinase inhibitors, the classical protein kinase C (cPKC) inhibitor Go6976, the novel PKC (nPKC) inhibitor Rottlerin, the protein kinase A (PKA) inhibitor H-89 and the protein tyrosine kinase (PTK) inhibitor herbimycin A at their optimum concentrations for 24 hr. CD93 expression was analyzed using flow cytometry and glutaraldehyde-fixed cellular enzyme-linked immunoassay (EIA) techniques utilizing a CD93 monoclonal antibody (mAb), mNI-11, that was originally established in our laboratory as a CD93 detection probe. The nPKC inhibitor Rottlerin strongly down-regulated CD93 expression on the U937 cells in a dose-dependent manner, whereas the other inhibitors had little or no effect. CD93 expression was down-regulated by Go6976, but not by Rottlerin, in the KHYG-1 cells and by both Rottlerin and Go6976 in the HUV-EC-C cells. The PKC stimulator, phorbol myristate acetate (PMA), strongly up-regulated CD93 expression on the cell surface of all three cell-lines and induced interleukin-8 (IL-8) production by the U937 cells and interferon-gamma (IFN-gamma) production by the KHYG-1 cells. In addition, both Go6976 and Rottlerin inhibited the up-regulation of CD93 expression induced by PMA and IL-8 or IFN-gamma production in the respective cell

Regulation of Chlamydia Gene Expression by Tandem Promoters with Different Temporal Patterns.

PubMed

Rosario, Christopher J; Tan, Ming

2016-01-15

Chlamydia is a genus of pathogenic bacteria with an unusual intracellular developmental cycle marked by temporal waves of gene expression. The three main temporal groups of chlamydial genes are proposed to be controlled by separate mechanisms of transcriptional regulation. However, we have noted genes with discrepancies, such as the early gene dnaK and the midcycle genes bioY and pgk, which have promoters controlled by the late transcriptional regulators EUO and σ(28). To resolve this issue, we analyzed the promoters of these three genes in vitro and in Chlamydia trachomatis bacteria grown in cell culture. Transcripts from the σ(28)-dependent promoter of each gene were detected only at late times in the intracellular infection, bolstering the role of σ(28) RNA polymerase in late gene expression. In each case, however, expression prior to late times was due to a second promoter that was transcribed by σ(66) RNA polymerase, which is the major form of chlamydial polymerase. These results demonstrate that chlamydial genes can be transcribed from tandem promoters with different temporal profiles, leading to a composite expression pattern that differs from the expression profile of a single promoter. In addition, tandem promoters allow a gene to be regulated by multiple mechanisms of transcriptional regulation, such as DNA supercoiling or late regulation by EUO and σ(28). We discuss how tandem promoters broaden the repertoire of temporal gene expression patterns in the chlamydial developmental cycle and can be used to fine-tune the expression of specific genes. Chlamydia is a pathogenic bacterium that is responsible for the majority of infectious disease cases reported to the CDC each year. It causes an intracellular infection that is characterized by coordinated expression of chlamydial genes in temporal waves. Chlamydial transcription has been shown to be regulated by DNA supercoiling, alternative forms of RNA polymerase, and transcription factors, but the number

The norepinephrine transporter and its regulation.

PubMed

Mandela, Prashant; Ordway, Gregory A

2006-04-01

For many years, the norepinephrine transporter (NET) was considered a 'static' protein that contributed to the termination of the action of norepinephrine in the synapse of noradrenergic neurons. The concept that the NET is dynamically regulated, adjusting noradrenergic transmission by changing its function and/or expression, was considered initially in the mid 1980s. Since that time, a plethora of studies demonstrate that the NET is regulated by several intracellular and extracellular signaling molecules, and that phosphorylation of the NET is a major pathway regulating its cell surface expression and thereby its function. The NET is a target of action of a number of drugs that are used long-term therapeutically or abused chronically. This has driven numerous investigations of how the NET and its function are regulated by long-term exposure to drugs. While repeated exposure to many drugs has been shown to affect NET function and expression, the intracellular mechanisms for these effects remains elusive.

Activated Leukocyte Cell Adhesion Molecule Expression and Shedding in Thyroid Tumors

PubMed Central

Miccichè, Francesca; Da Riva, Luca; Fabbi, Marina; Pilotti, Silvana; Mondellini, Piera; Ferrini, Silvano; Canevari, Silvana; Pierotti, Marco A.; Bongarzone, Italia

2011-01-01

Activated leukocyte cell adhesion molecule (ALCAM, CD166) is expressed in various tissues, cancers, and cancer-initiating cells. Alterations in expression of ALCAM have been reported in several human tumors, and cell adhesion functions have been proposed to explain its association with cancer. Here we documented high levels of ALCAM expression in human thyroid tumors and cell lines. Through proteomic characterization of ALCAM expression in the human papillary thyroid carcinoma cell line TPC-1, we identified the presence of a full-length membrane-associated isoform in cell lysate and of soluble ALCAM isoforms in conditioned medium. This finding is consistent with proteolytically shed ALCAM ectodomains. Nonspecific agents, such as phorbol myristate acetate (PMA) or ionomycin, provoked increased ectodomain shedding. Epidermal growth factor receptor stimulation also enhanced ALCAM secretion through an ADAM17/TACE-dependent pathway. ADAM17/TACE was expressed in the TPC-1 cell line, and ADAM17/TACE silencing by specific small interfering RNAs reduced ALCAM shedding. In addition, the CGS27023A inhibitor of ADAM17/TACE function reduced ALCAM release in a dose-dependent manner and inhibited cell migration in a wound-healing assay. We also provide evidence for the existence of novel O-glycosylated forms and of a novel 60-kDa soluble form of ALCAM, which is particularly abundant following cell stimulation by PMA. ALCAM expression in papillary and medullary thyroid cancer specimens and in the surrounding non-tumoral component was studied by western blot and immunohistochemistry, with results demonstrating that tumor cells overexpress ALCAM. These findings strongly suggest the possibility that ALCAM may have an important role in thyroid tumor biology. PMID:21364949

Identification of a regulatory T cell specific cell surface molecule that mediates suppressive signals and induces Foxp3 expression.

PubMed

Wang, Rui; Wan, Qi; Kozhaya, Lina; Fujii, Hodaka; Unutmaz, Derya

2008-07-16

Regulatory T (T(reg)) cells control immune activation and maintain tolerance. How T(regs) mediate their suppressive function is unclear. Here we identified a cell surface molecule, called GARP, (or LRRC32), which within T cells is specifically expressed in T(regs) activated through the T cell receptor (TCR). Ectopic expression of GARP in human naïve T (T(N)) cells inhibited their proliferation and cytokine secretion upon TCR activation. Remarkably, GARP over-expression in T(N) cells induced expression of T(reg) master transcription factor Foxp3 and endowed them with a partial suppressive function. The extracellular but not the cytoplasmic region of GARP, was necessary for these functions. Silencing Foxp3 in human T(reg) cells reduced expression of GARP and attenuated their suppressive function. However, GARP function was not affected when Foxp3 was downregulated in GARP-overexpressing cells, while silencing GARP in Foxp3-overexpressing cells reduced their suppressive activity. These findings reveal a novel cell surface molecule-mediated regulatory mechanism, with implications for modulating aberrant immune responses.

The PBX1 lupus susceptibility gene regulates CD44 expression.

PubMed

Niu, Yuxin; Sengupta, Mayami; Titov, Anton A; Choi, Seung-Chul; Morel, Laurence

2017-05-01

PBX1-d is novel splice isoform of pre-B-cell leukemia homeobox 1 (PBX1) that lacks its DNA-binding and Hox-binding domains, and functions as a dominant negative. We have shown that PBX1-d expression in CD4 + T cells is associated with systemic lupus erythematosus (SLE) in a mouse model as well as in human subjects. More specifically, PBX1-d expression leads to the production of autoreactive activated CD4+ T cells, a reduced frequency and function of Foxp3+ regulatory T (Treg) cells and an expansion of follicular helper T (Tfh) cells. Very little is known about the function of PBX1 in T cells, except that it directly regulates the expression of miRNAs associated with Treg and Tfh homeostasis. In the present study, we show that PBX1 directly regulated the expression of CD44, a marker of T cell activation. Two PBX1 binding sites in the promoter directly regulated CD44 expression, with PBX1-d driving a higher expression than the normal isoform PBX1-b. In addition, mutations in each of the two binding sites had different effects of PBX1-b and PBX1-d. Finally, we showed that an enhanced recruitment of co-factor MEIS by PBX1-d over PBX1-b, while there was no difference for co-factor PREP1 recruitment. Therefore, this study demonstrates that the lupus-associated PBX1-d isoform directly transactivates CD44, a marker of CD44 activation and memory, and that it has different DNA binding and co-factor recruitment relative to the normal isoform. Taken together, these results confirm that PBX1 directly regulates genes related to T cell activation and shows that the lupus-associated isoform PBX1-d has unique molecular functions. Copyright © 2017 Elsevier Ltd. All rights reserved.

The PBX1 lupus susceptibility gene regulates CD44 expression

PubMed Central

Niu, Yuxin; Sengupta, Mayami; Titov, Anton A.; Choi, Seung-Chul; Morel, Laurence

2017-01-01

PBX1-d is novel splice isoform of pre-B-cell leukemia homeobox 1 (PBX1) that lacks its DNA-binding and Hox-binding domains, and functions as a dominant negative. We have shown that PBX1-d expression in CD4+ T cells is associated with systemic lupus erythematosus (SLE) in a mouse model as well as in human subjects. More specifically, PBX1-d expression leads to the production of autoreactive activated CD4+ T cells, a reduced frequency and function of Foxp3+ regulatory T (Treg) cells and an expansion of follicular helper T (Tfh) cells. Very little is known about the function of PBX1 in T cells, except that it directly regulates the expression of miRNAs associated with Treg and Tfh homeostasis. In the present study, we show that PBX1 directly regulated the expression of CD44, a marker of T cell activation. Two PBX1 binding sites in the promoter directly regulated CD44 expression, with PBX1-d driving a higher expression than the normal isoform PBX1-b. In addition, mutations in each of the two binding sites had different effects of PBX1-b and PBX1-d. Finally, we showed that an enhanced recruitment of co-factor MEIS by PBX1-d over PBX1-b, while there was no difference for co-factor PREP1 recruitment. Therefore, this study demonstrates that the lupus-associated PBX1-d isoform directly transactivates CD44, a marker of CD44 activation and memory, and that it has different DNA binding and co-factor recruitment relative to the normal isoform. Taken together, these results confirm that PBX1 directly regulates genes related to T cell activation and show that the lupus-associated isoform PBX1-d has unique molecular functions. PMID:28257976

Epigenetic regulation of serotype expression antagonizes transcriptome dynamics in Paramecium tetraurelia.

PubMed

Cheaib, Miriam; Dehghani Amirabad, Azim; Nordström, Karl J V; Schulz, Marcel H; Simon, Martin

2015-08-01

Phenotypic variation of a single genotype is achieved by alterations in gene expression patterns. Regulation of such alterations depends on their time scale, where short-time adaptations differ from permanently established gene expression patterns maintained by epigenetic mechanisms. In the ciliate Paramecium, serotypes were described for an epigenetically controlled gene expression pattern of an individual multigene family. Paradoxically, individual serotypes can be triggered in Paramecium by alternating environments but are then stabilized by epigenetic mechanisms, thus raising the question to which extend their expression follows environmental stimuli. To characterize environmental adaptation in the context of epigenetically controlled serotype expression, we used RNA-seq to characterize transcriptomes of serotype pure cultures. The resulting vegetative transcriptome resource is first analysed for genes involved in the adaptive response to the altered environment. Secondly, we identified groups of genes that do not follow the adaptive response but show co-regulation with the epigenetically controlled serotype system, suggesting that their gene expression pattern becomes manifested by similar mechanisms. In our experimental set-up, serotype expression and the entire group of co-regulated genes were stable among environmental changes and only heat-shock genes altered expression of these gene groups. The data suggest that the maintenance of these gene expression patterns in a lineage represents epigenetically controlled robustness counteracting short-time adaptation processes. © The Author 2015. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.

DNA-Demethylase Regulated Genes Show Methylation-Independent Spatiotemporal Expression Patterns

PubMed Central

Schumann, Ulrike; Lee, Joanne; Kazan, Kemal; Ayliffe, Michael; Wang, Ming-Bo

2017-01-01

Recent research has indicated that a subset of defense-related genes is downregulated in the Arabidopsis DNA demethylase triple mutant rdd (ros1 dml2 dml3) resulting in increased susceptibility to the fungal pathogen Fusarium oxysporum. In rdd plants these downregulated genes contain hypermethylated transposable element sequences (TE) in their promoters, suggesting that this methylation represses gene expression in the mutant and that these sequences are actively demethylated in wild-type plants to maintain gene expression. In this study, the tissue-specific and pathogen-inducible expression patterns of rdd-downregulated genes were investigated and the individual role of ROS1, DML2, and DML3 demethylases in these spatiotemporal regulation patterns was determined. Large differences in defense gene expression were observed between pathogen-infected and uninfected tissues and between root and shoot tissues in both WT and rdd plants, however, only subtle changes in promoter TE methylation patterns occurred. Therefore, while TE hypermethylation caused decreased gene expression in rdd plants it did not dramatically effect spatiotemporal gene regulation, suggesting that this latter regulation is largely methylation independent. Analysis of ros1-3, dml2-1, and dml3-1 single gene mutant lines showed that promoter TE hypermethylation and defense-related gene repression was predominantly, but not exclusively, due to loss of ROS1 activity. These data demonstrate that DNA demethylation of TE sequences, largely by ROS1, promotes defense-related gene expression but does not control spatiotemporal expression in Arabidopsis. Summary: Ros1-mediated DNA demethylation of promoter transposable elements is essential for activation of defense-related gene expression in response to fungal infection in Arabidopsis thaliana. PMID:28894455

The Pseudomonas aeruginosa quorum sensing signal molecule N-(3-oxododecanoyl) homoserine lactone enhances keratinocyte migration and induces Mmp13 gene expression in vitro

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

Paes, Camila, E-mail: camilaquinetti@gmail.com; Nakagami, Gojiro, E-mail: gojiron-tky@umin.ac.jp; Minematsu, Takeo, E-mail: tminematsu-tky@umin.ac.jp

2012-10-19

Highlights: Black-Right-Pointing-Pointer An evidence of the positive effect of AHL on epithelialization process is provided. Black-Right-Pointing-Pointer AHL enhances keratinocyte's ability to migrate in an in vitro scratch wound model. Black-Right-Pointing-Pointer AHL induces the expression of Mmp13. Black-Right-Pointing-Pointer Topical application of AHL represents a possible strategy to treat chronic wounds. -- Abstract: Re-epithelialization is an essential step of wound healing involving three overlapping keratinocyte functions: migration, proliferation and differentiation. While quorum sensing (QS) is a cell density-dependent signaling system that enables bacteria to regulate the expression of certain genes, the QS molecule N-(3-oxododecanoyl) homoserine lactone (AHL) exerts effects also on mammalianmore » cells in a process called inter-kingdom signaling. Recent studies have shown that AHL improves epithelialization in in vivo wound healing models but detailed understanding of the molecular and cellular mechanisms are needed. The present study focused on the AHL as a candidate reagent to improve wound healing through direct modulation of keratinocyte's activity in the re-epithelialization process. Results indicated that AHL enhances the keratinocyte's ability to migrate in an in vitro scratch wound healing model probably due to the high Mmp13 gene expression analysis after AHL treatment that was revealed by real-time RT-PCR. Inhibition of activator protein 1 (AP-1) signaling pathway completely prevented the migration of keratinocytes, and also resulted in a diminished Mmp13 gene expression, suggesting that AP-1 might be essential in the AHL-induced migration. Taken together, these results imply that AHL is a promising candidate molecule to improve re-epithelialization through the induction of migration of keratinocytes. Further investigation is needed to clarify the mechanism of action and molecular pathway of AHL on the keratinocyte migration process.« less

Transcriptional regulation of brain gene expression in response to a territorial intrusion

PubMed Central

Sanogo, Yibayiri O.; Band, Mark; Blatti, Charles; Sinha, Saurabh; Bell, Alison M.

2012-01-01

Aggressive behaviour associated with territorial defence is widespread and has fitness consequences. However, excess aggression can interfere with other important biological functions such as immunity and energy homeostasis. How the expression of complex behaviours such as aggression is regulated in the brain has long intrigued ethologists, but has only recently become amenable for molecular dissection in non-model organisms. We investigated the transcriptomic response to territorial intrusion in four brain regions in breeding male threespined sticklebacks using expression microarrays and quantitative polymerase chain reaction (qPCR). Each region of the brain had a distinct genomic response to a territorial challenge. We identified a set of genes that were upregulated in the diencephalon and downregulated in the cerebellum and the brain stem. Cis-regulatory network analysis suggested transcription factors that regulated or co-regulated genes that were consistently regulated in all brain regions and others that regulated gene expression in opposing directions across brain regions. Our results support the hypothesis that territorial animals respond to social challenges via transcriptional regulation of genes in different brain regions. Finally, we found a remarkably close association between gene expression and aggressive behaviour at the individual level. This study sheds light on the molecular mechanisms in the brain that underlie the response to social challenges. PMID:23097509

ERK1/2 mediates glucose-regulated POMC gene expression in hypothalamic neurons.

PubMed

Zhang, Juan; Zhou, Yunting; Chen, Cheng; Yu, Feiyuan; Wang, Yun; Gu, Jiang; Ma, Lian; Ho, Guyu

2015-04-01

Hypothalamic glucose-sensing neurons regulate the expression of genes encoding feeding-related neuropetides POMC, AgRP, and NPY - the key components governing metabolic homeostasis. AMP-activated protein kinase (AMPK) is postulated to be the molecular mediator relaying glucose signals to regulate the expression of these neuropeptides. Whether other signaling mediator(s) plays a role is not clear. In this study, we investigated the role of ERK1/2 using primary hypothalamic neurons as the model system. The primary neurons were differentiated from hypothalamic progenitor cells. The differentiated neurons possessed the characteristic neuronal cell morphology and expressed neuronal post-mitotic markers as well as leptin-regulated orexigenic POMC and anorexigenic AgRP/NPY genes. Treatment of cells with glucose dose-dependently increased POMC and decreased AgRP/NPY expression with a concurrent suppression of AMPK phosphorylation. In addition, glucose treatment dose-dependently increased the ERK1/2 phosphorylation. Blockade of ERK1/2 activity with its specific inhibitor PD98059 partially (approximately 50%) abolished glucose-induced POMC expression, but had little effect on AgRP/NPY expression. Conversely, blockade of AMPK activity with its specific inhibitor produced a partial (approximately 50%) reversion of low-glucose-suppressed POMC expression, but almost completely blunted the low-glucose-induced AgRP/NPY expression. The results indicate that ERK1/2 mediated POMC but not AgRP/NPY expression. Confirming the in vitro findings, i.c.v. administration of PD98059 in rats similarly attenuated glucose-induced POMC expression in the hypothalamus, but again had little effect on AgRP/NPY expression. The results are indicative of a novel role of ERK1/2 in glucose-regulated POMC expression and offer new mechanistic insights into hypothalamic glucose sensing. © 2015 Society for Endocrinology.

Chronology and regulation of gene expression of RANKL in the rat dental follicle.

PubMed

Liu, D; Yao, S; Pan, F; Wise, G E

2005-10-01

Tooth eruption in the rat requires bone resorption resulting from a major burst of osteoclastogenesis on postnatal day 3 and a minor burst of osteoclastogenesis on postnatal day 10 in the alveolar bone of the first mandibular molar. The dental follicle regulates the major burst on postnatal day 3 by down-regulating its osteoprotegerin (OPG) gene expression to enable osteoclastogenesis to occur. To determine the role of receptor activator of nuclear factor-kappa B ligand (RANKL) in tooth eruption, its gene expression was measured on postnatal days 1-11 in the dental follicle. The results show that RANKL expression was significantly elevated on postnatal days 9-11 in comparison to low expression levels at earlier time-points. As OPG expression is high at this latter time-point, this increase in RANKL expression would be needed for stimulating the minor burst of osteoclastogenesis. Tumor necrosis factor-alpha enhances RANKL gene expression in vitro and it may be responsible for up-regulating RANKL in vivo. Transforming growth factor-beta1 and interleukin-1alpha also enhance RANKL gene expression in vitro but probably have no effect in vivo because they are maximally expressed early. Bone morphogenetic protein-2 acts to down-regulate RANKL expression in vitro and, in vivo, may promote alveolar bone growth in the basal region of the tooth.

Controlling Destiny through Chemistry: Small-Molecule Regulators of Cell Fate

PubMed Central

2009-01-01

Controlling cell fate is essential for embryonic development, tissue regeneration, and the prevention of human disease. With each cell in the human body sharing a common genome, achieving the appropriate spectrum of stem cells and their differentiated lineages requires the selective activation of developmental signaling pathways, the expression of specific target genes, and the maintenance of these cellular states through epigenetic mechanisms. Small molecules that target these regulatory processes are therefore valuable tools for probing and manipulating the molecular mechanisms by which stem cells self-renew, differentiate, and arise from somatic cell reprogramming. Pharmacological modulators of cell fate could also help remediate human diseases caused by dysregulated cell proliferation or differentiation, heralding a new era in molecular therapeutics. PMID:20000447

Identification of cell density signal molecule

DOEpatents

Schwarz, R.I.

1998-04-21

Disclosed herein is a novel proteinaceous cell density signal molecule (CDS) between 25 and 35 kD, which is secreted by fibroblastic primary avian tendon cells in culture, and causes the cells to self-regulate their proliferation and the expression of differentiated function. It effects an increase of procollagen production in avian tendon cell cultures of ten fold while proliferation rates are decreased. CDS, and the antibodies which recognize them, are important for the development of diagnostics and treatments for injuries and diseases involving connective tissues, particularly tendon. Also disclosed are methods of production and use. 2 figs.

Identification of cell density signal molecule

DOEpatents

Schwarz, Richard I.

1998-01-01

Disclosed herein is a novel proteinaceous cell density signal molecule (CDS) between 25 and 35 kD, which is secreted by fibroblastic primary avian tendon cells in culture, and causes the cells to self-regulate their proliferation and the expression of differentiated function. It effects an increase of procollagen production in avian tendon cell cultures of ten fold while proliferation rates are decreased. CDS, and the antibodies which recognize them, are important for the development of diagnostics and treatments for injuries and diseases involving connective tissues, particularly tendon. Also disclosed are methods of production and use.

Rapamycin regulates the proliferation of Huh7, a hepatocellular carcinoma cell line, by up-regulating p53 expression

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

Kwon, Sora; Jeon, Ji-Sook; Ahn, Curie

Rapamycin, a specific inhibitor of mTOR used extensively as an immunosuppressant, has been expanded recently to cancer therapy, because the mTOR signal is known to be up-regulated in various cancer cells including hepatocellular carcinoma (HCC) cells. In spite of extensive efforts to employ mTOR inhibitors as anti-HCC therapy, they have not yet been approved by the FDA. Because of the heterogeneity and complexity of molecular signaling in HCC, suitable biomarkers should be identified or discovered to improve clinical efficacy of mTOR-specific inhibitors to HCC cells. In this study, the effect of rapamycin was investigated on two different HCC cell lines,more » Huh7 cells and HepG2 cells. Rapamycin was found to inhibit the proliferation of Huh7 cells but not of HepG2 cells. Moreover, it was found that rapamycin can up-regulate p53 at the protein level, but not affect its transcript. To understand the critical role of p53 in the rapamycin effect, knock-down experiments were performed using small-interfering RNAs (siRNAs). The anti-proliferative effect of rapamycin on Huh7 cells clearly disappeared after blocking p53 production with siRNA, which indicates that p53 is a critical factor in the anti-proliferative effect of rapamycin in HCC cells. The over-expression system of p53 was also employed to mimic the effect of rapamycin and found that cell proliferation was clearly down-regulated by p53 over-expression. Finally, we found that the extracellular signal-regulated kinase 1/2 (ERK1/2) signal was regulated by p53 whose expression was induced by rapamycin. Overall, this study demonstrates that rapamycin inhibited the proliferation of Huh7 cells by up-regulating the expression of p53 and down-regulating the ERK1/2 signal, indicating that p53 is a useful biomarker for anti-cancer therapy using the specific inhibitor of mTOR signal, rapamycin, against hepatocellular carcinoma cells. - Highlights: • Rapamycin inhibits the proliferation of hepatocellular carcinoma

Glucose Regulates the Expression of the Apolipoprotein A5 Gene

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

Fruchart, Jamila; Nowak, Maxime; Helleboid-Chapman, Audrey

2008-04-07

The apolipoprotein A5 gene (APOA5) is a key player in determining triglyceride concentrations in humans and mice. Since diabetes is often associated with hypertriglyceridemia, this study explores whether APOA5 gene expression is regulated by alteration in glucose homeostasis and the related pathways. D-glucose activates APOA5 gene expression in a time- and dose-dependent manner in hepatocytes, and the glycolytic pathway involved was determined using D-glucose analogs and metabolites. Together, transient transfections, electrophoretic mobility shift assays and chromatin immunoprecipitation assays show that this regulation occurs at the transcriptional level through an increase of USF1/2 binding to an E-box in the APOA5 promoter.more » We show that this phenomenon is not due to an increase of mRNA or protein expression levels of USF. Using protein phosphatases 1 and 2A inhibitor, we demonstrate that D-glucose regulates APOA5 gene via a dephosphorylation mechanism, thereby resulting in an enhanced USF1/2-promoter binding. Last, subsequent suppressions of USF1/2 and phosphatases mRNA through siRNA gene silencing abolished the regulation. We demonstrate that APOA5 gene is up regulated by D-glucose and USF through phosphatase activation. These findings may provide a new cross talk between glucose and lipid metabolism.« less

Glutamine supplementation attenuates expressions of adhesion molecules and chemokine receptors on T cells in a murine model of acute colitis.

PubMed

Hou, Yu-Chen; Wu, Jin-Ming; Wang, Ming-Yang; Wu, Ming-Hsun; Chen, Kuen-Yuan; Yeh, Sung-Ling; Lin, Ming-Tsan

2014-01-01

Migration of T cells into the colon plays a major role in the pathogenesis in inflammatory bowel disease. This study investigated the effects of glutamine (Gln) supplementation on chemokine receptors and adhesion molecules expressed by T cells in mice with dextran sulfate sodium- (DSS-) induced colitis. C57BL/6 mice were fed either a standard diet or a Gln diet replacing 25% of the total nitrogen. After being fed the diets for 5 days, half of the mice from both groups were given 1.5% DSS in drinking water to induce colitis. Mice were killed after 5 days of DSS exposure. DSS colitis resulted in higher expression levels of P-selectin glycoprotein ligand- (PSGL-) 1, leukocyte function-associated antigen- (LFA-) 1, and C-C chemokine receptor type 9 (CCR9) by T helper (Th) and cytotoxic T (Tc) cells, and mRNA levels of endothelial adhesion molecules in colons were upregulated. Gln supplementation decreased expressions of PSGL-1, LFA-1, and CCR9 by Th cells. Colonic gene expressions of endothelial adhesion molecules were also lower in Gln-colitis mice. Histological finding showed that colon infiltrating Th cells were less in the DSS group with Gln administration. Gln supplementation may ameliorate the inflammation of colitis possibly via suppression of T cell migration.

Cell Cycle Regulation of Stem Cells by MicroRNAs.

PubMed

Mens, Michelle M J; Ghanbari, Mohsen

2018-06-01

MicroRNAs (miRNAs) are a class of small non-coding RNA molecules involved in the regulation of gene expression. They are involved in the fine-tuning of fundamental biological processes such as proliferation, differentiation, survival and apoptosis in many cell types. Emerging evidence suggests that miRNAs regulate critical pathways involved in stem cell function. Several miRNAs have been suggested to target transcripts that directly or indirectly coordinate the cell cycle progression of stem cells. Moreover, previous studies have shown that altered expression levels of miRNAs can contribute to pathological conditions, such as cancer, due to the loss of cell cycle regulation. However, the precise mechanism underlying miRNA-mediated regulation of cell cycle in stem cells is still incompletely understood. In this review, we discuss current knowledge of miRNAs regulatory role in cell cycle progression of stem cells. We describe how specific miRNAs may control cell cycle associated molecules and checkpoints in embryonic, somatic and cancer stem cells. We further outline how these miRNAs could be regulated to influence cell cycle progression in stem cells as a potential clinical application.

Expression of POEM, a positive regulator of osteoblast differentiation, is suppressed by TNF-{alpha}

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

Tsukasaki, Masayuki; Yamada, Atsushi, E-mail: yamadaa@dent.showa-u.ac.jp; Suzuki, Dai

2011-07-15

Highlights: {yields} TNF-{alpha} inhibits POEM gene expression. {yields} Inhibition of POEM gene expression is caused by NF-{kappa}B activation by TNF-{alpha}. {yields} Over-expression of POEM recovers inhibition of osteoblast differentiation by TNF-{alpha}. -- Abstract: POEM, also known as nephronectin, is an extracellular matrix protein considered to be a positive regulator of osteoblast differentiation. In the present study, we found that tumor necrosis factor-{alpha} (TNF-{alpha}), a key regulator of bone matrix properties and composition that also inhibits terminal osteoblast differentiation, strongly inhibited POEM expression in the mouse osteoblastic cell line MC3T3-E1. TNF-{alpha}-induced down-regulation of POEM gene expression occurred in both time- andmore » dose-dependent manners through the nuclear factor kappa B (NF-{kappa}B) pathway. In addition, expressions of marker genes in differentiated osteoblasts were down-regulated by TNF-{alpha} in a manner consistent with our findings for POEM, while over-expression of POEM recovered TNF-{alpha}-induced inhibition of osteoblast differentiation. These results suggest that TNF-{alpha} inhibits POEM expression through the NF-{kappa}B signaling pathway and down-regulation of POEM influences the inhibition of osteoblast differentiation by TNF-{alpha}.« less

Regulation of ITAM adaptor molecules and their receptors by inhibition of calcineurin-NFAT signalling during late stage osteoclast differentiation

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

Zawawi, M.S.F.; Discipline of Anatomy and Pathology, School of Medical Sciences, University of Adelaide, Adelaide, SA 5005; Dharmapatni, A.A.S.S.K.