Note: This page contains sample records for the topic factor sp1 plays from Science.gov.
While these samples are representative of the content of Science.gov,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of Science.gov
to obtain the most current and comprehensive results.
Last update: November 12, 2013.
1

Transcription Factor Sp1 Plays an Important Role in the Regulation of Copper Homeostasis in Mammalian Cells  

PubMed Central

Copper is an essential metal nutrient, yet Cu overload is toxic. Here, we report that human copper transporter 1 (hCtr1) plays an important role in the maintenance of Cu homeostasis by demonstrating that expression of hCtr1 mRNA was up-regulated under Cu-depleted conditions and down-regulated under Cu-replete conditions. Overexpression of full-length hCtr1 by transfection with a recombinant hCtr1 cDNA clone reduced endogenous hCtr1 mRNA levels, whereas overexpression of N-terminus-deleted hCtr1 did not change endogenous hCtr1 mRNA levels, suggesting that increased functional hCtr1 transporter, which leads to increased intracellular Cu contents down-regulates the endogenous hCtr1 mRNA. A luciferase assay using reporter constructs containing the hCtr1 promoter sequences revealed that three Sp1-binding sites are involved in the basal and Cu concentration-dependent regulation of hCtr1 expression. Modulation of Sp1 levels affected the expression of hCtr1. We further demonstrated that zinc finger domain of Sp1 functions as a sensor of Cu that regulates hCtr1 up-and-down in response to Cu concentration variations. Our results demonstrate that mammalian Cu homeostasis is maintained at the hCtr1 mRNA level which is regulated by the Sp1 transcription factor.

Song, Im-Sook; Chen, Helen H. W.; Aiba, Isamu; Hossain, Anwar; Liang, Zheng D.; Klomp, Leo W. J.; Kuo, Macus Tien

2008-01-01

2

Transcription factors Sp1 and Sp4 regulate TRPV1 gene expression in rat sensory neurons  

PubMed Central

Background The capsaicin receptor, transient receptor potential vanilloid type -1 (TRPV1) directs complex roles in signal transduction including the detection of noxious stimuli arising from cellular injury and inflammation. Under pathophysiologic conditions, TRPV1 mRNA and receptor protein expression are elevated in dorsal root ganglion (DRG) neurons for weeks to months and is associated with hyperalgesia. Building on our previous isolation of a promoter system for the rat TRPV1 gene, we investigated the proximal TRPV1 P2-promoter by first identifying candidate Sp1-like transcription factors bound in vivo to the P2-promoter using chromatin immunoprecipitation (ChIP) assay. We then performed deletion analysis of GC-box binding sites, and quantified promoter activity under conditions of Sp1 / Sp4 over-expression versus inhibition/knockdown. mRNA encoding Sp1, Sp4 and TRPV1 were quantified by qRT-PCR under conditions of Sp1/Sp4 over-expression or siRNA mediated knockdown in cultured DRG neurons. Results Using ChIP analysis of DRG tissue, we demonstrated that Sp1 and Sp4 are bound to the candidate GC-box site region within the endogenous TRPV1 P2-promoter. Deletion of GC-box "a" or "a + b" within the P2- promoter resulted in a complete loss of transcriptional activity indicating that GC-box "a" was the critical site for promoter activation. Co-transfection of Sp1 increased P2-promoter activity in cultured DRG neurons whereas mithramycin-a, an inhibitor of Sp1-like function, dose dependently blocked NGF and Sp1-dependent promoter activity in PC12 cells. Co-transfection of siRNA directed against Sp1 or Sp4 decreased promoter activity in DRG neurons and NGF treated PC12 cells. Finally, electroporation of Sp1 or Sp4 cDNA into cultures of DRG neurons directed an increase in Sp1/Sp4 mRNA and importantly an increase in TRPV1 mRNA. Conversely, combined si-RNA directed knockdown of Sp1/Sp4 resulted in a decrease in TRPV1 mRNA. Conclusion Based on these studies, we now propose a model of TRPV1 expression that is dependent on Sp1-like transcription factors with Sp4 playing a predominant role in activating TRPV1 RNA transcription in DRG neurons. Given that increases of TRPV1 expression have been implicated in a wide range of pathophysiologic states including persistent painful conditions, blockade of Sp1-like transcription factors represents a novel direction in therapeutic strategies.

2011-01-01

3

SP1 plays a pivotal role for basal activity of TIGAR promoter in liver cancer cell lines  

Microsoft Academic Search

TIGAR expression resulted in down-regulation of glycolysis, reduction of intracellular levels of reactive oxygen species,\\u000a and protection from apoptosis. Despite biological importance, its promoter has not yet been characterized. In this study,\\u000a we characterized that transcription factor SP1 plays a pivotal role for basal activity of TIGAR promoter. By 5?RACE, the transcription\\u000a start site was identified locating at 134 bp upstream

Shubiao Zou; Zhidong Gu; Peihua Ni; Xiangfan Liu; Jiayi Wang; Qishi Fan

4

Ischemia/Reperfusion Reduces Transcription Factor Sp1-mediated Cystathionine ?-Synthase Expression in the Kidney*  

PubMed Central

Cystathionine ?-synthase (CBS) is a key enzyme that catalyzes the rate-limiting step for homocysteine (Hcy) metabolism via the trans-sulfuration pathway and is also responsible for the production of H2S through the desulfhydration reaction. Our recent studies demonstrate that renal ischemia/reperfusion decreased the CBS activity leading to Hcy accumulation and H2S reduction in the kidney, which in turn contributed to kidney injury. Both Hcy and H2S play important roles in physiological and pathological processes. In this study we investigated the molecular mechanism by which CBS activity was regulated in the kidney. The left kidney of Sprague-Dawley rat was subjected to 45 min of ischemia followed by 6 h of reperfusion. Ischemia/reperfusion caused a significant decrease in CBS mRNA and protein levels in the kidney. As a consequence, there was a marked reduction in the CBS enzyme activity. Transfection of kidney proximal tubular cells with transcription factor (Sp1) small interfering RNA caused a marked reduction in CBS mRNA, indicating a pivotal role for Sp1 in regulating CBS expression in kidney cells. Electrophoretic mobility shift assay and chromatin immunoprecipitation assay detected a lower Sp1 activity in kidneys subjected to ischemia/reperfusion as compared with that in a sham-operated group. ERK-mediated phosphorylation of Sp1 was responsible for a decreased transcriptional activity of Sp1 in the kidney upon ischemia/reperfusion. These results suggest that reduced kidney CBS gene expression during ischemia/reperfusion is mediated via a decrease in Sp1 transcriptional activity. Regulation of CBS-mediated Hcy and H2S homeostasis may offer a renal protective effect against ischemia/reperfusion injury.

Wu, Nan; Siow, Yaw L.; O, Karmin

2010-01-01

5

Role of zinc finger structure in nuclear localization of transcription factor Sp1  

SciTech Connect

Transcription factor Sp1 is localized in the nucleus and regulates gene expression. Our previous study demonstrated that the carboxyl terminal region of Sp1 containing 3-zinc finger region as DNA binding domain can also serve as nuclear localization signal (NLS). However, the nuclear transport mechanism of Sp1 has not been well understood. In this study, we performed a gene expression study on mutant Sp1 genes causing a set of amino acid substitutions in zinc finger domains to elucidate nuclear import activity. Nuclear localization of the GFP-fused mutant Sp1 proteins bearing concomitant substitutions in the first and third zinc fingers was highly inhibited. These mutant Sp1 proteins had also lost the binding ability as to the GC box sequence. The results suggest that the overall tertiary structure formed by the three zinc fingers is essential for nuclear localization of Sp1 as well as dispersed basic amino acids within the zinc fingers region.

Ito, Tatsuo; Azumano, Makiko [Department of Medicinal Biotechnology, Institute for Medicinal Research, Graduate School of Pharmaceutical Sciences, University of Tokushima, 1-78 Sho-machi, Tokushima 770-8505 (Japan); Uwatoko, Chisana [Faculty of Pharmaceutical Sciences, Doshisha Women's University, Kodo, Kyotanabe City, 610-0395 (Japan); Itoh, Kohji [Department of Medicinal Biotechnology, Institute for Medicinal Research, Graduate School of Pharmaceutical Sciences, University of Tokushima, 1-78 Sho-machi, Tokushima 770-8505 (Japan)], E-mail: kitoh@ph.tokushima-u.ac.jp; Kuwahara, Jun [Department of Medicinal Biotechnology, Institute for Medicinal Research, Graduate School of Pharmaceutical Sciences, University of Tokushima, 1-78 Sho-machi, Tokushima 770-8505 (Japan); Faculty of Pharmaceutical Sciences, Doshisha Women's University, Kodo, Kyotanabe City, 610-0395 (Japan)], E-mail: jkuwahar@dwc.doshisha.ac.jp

2009-02-27

6

Elevated SP-1 transcription factor expression and activity drives basal and hypoxia-induced vascular endothelial growth factor (VEGF) expression in non-small cell lung cancer.  

PubMed

VEGF plays a central role in angiogenesis in cancer. Non-small cell lung cancer (NSCLC) tumors have increased microvascular density, localized hypoxia, and high VEGF expression levels; however, there is a lack of understanding of how oncogenic and tumor microenvironment changes such as hypoxia lead to greater VEGF expression in lung and other cancers. We show that NSCLC cells secreted higher levels of VEGF than normal airway epithelial cells. Actinomycin D inhibited all NSCLC VEGF secretion, and VEGF minimal promoter-luciferase reporter constructs were constitutively active until the last 85 base pairs before the transcription start site containing three SP-1 transcription factor-binding sites; mutation of these VEGF promoter SP-1-binding sites eliminated VEGF promoter activity. Furthermore, dominant negative SP-1, mithramycin A, and SP-1 shRNA decreased VEGF promoter activity, whereas overexpression of SP-1 increased VEGF promoter activity. Chromatin immunoprecipitation assays demonstrated SP-1, p300, and PCA/F histone acetyltransferase binding and histone H4 hyperacetylation at the VEGF promoter in NSCLC cells. Cultured NSCLC cells expressed higher levels of SP-1 protein than normal airway epithelial cells, and double-fluorescence immunohistochemistry showed a strong correlation between SP-1 and VEGF in human NSCLC tumors. In addition, hypoxia-driven VEGF expression in NSCLC cells was SP-1-dependent, with hypoxia increasing SP-1 activity and binding to the VEGF promoter. These studies are the first to demonstrate that overexpression of SP-1 plays a central role in hypoxia-induced VEGF secretion. PMID:22992725

Deacon, Karl; Onion, David; Kumari, Rajendra; Watson, Susan A; Knox, Alan J

2012-09-18

7

Activation of human papillomavirus type 18 E6-E7 oncogene expression by transcription factor Sp1.  

PubMed Central

The human papillomavirus 18 (HPV18) E6 and E7 proteins are considered to be primarily responsive for the transforming activity of the virus. In order to analyse the molecular mechanisms resulting in viral oncoprotein expression, it is necessary to identify the factors involved in the transcriptional regulation of the E6/E7 genes. Here we define by gel retardation experiments a sequence aberrant Sp1 binding site present in the promoter proximal part of the viral transcriptional control region (Upstream Regulatory Region, URR). Functional analyses employing transient reporter assays reveal that this Sp1 element is required for an efficient stimulation of the HPV18 E6/E7-promoter. Mutation of the Sp1 element in the natural context of the HPV18 URR leads to a strong decrease in the activity of the E6/E7-promoter in several cell lines. The magnitude of reduction varies between different cell types and is higher in cell lines of epithelial origin when compared with nonepithelial cells. Cotransfection assays using Sp1 expression vector systems further define the promoter proximal HPV18 Sp1 binding motif as a functional Sp1 element in vivo and show that its integrity is essential for the stimulation of the E6/E7-promoter by augmented levels of Sp1. These results indicate, that the cellular transcription factor Sp1 plays an important role for the stimulation of the E6/E7-promoter by the viral URR and represents a major determinant for the expression of HPV18 transforming genes E6 and E7. Images

Hoppe-Seyler, F; Butz, K

1992-01-01

8

The transcription factor Sp1 is responsible for aging-dependent altered nucleocytoplasmic trafficking.  

PubMed

Hyporesponsiveness to external signals, such as growth factors and apoptotic stimuli, is a cardinal feature of cellular senescence. We previously reported that an aging-dependent marked reduction in nucleocytoplasmic trafficking (NCT)-related genes could be responsible for this phenomenon. In searching for the mechanism, we identified the transcription factor, Sp1, as a common regulator of NCT genes, including various nucleoporins, importins, exportins, and Ran GTPase cycle-related genes. Sp1 knockdown led to a reduction of those genes in young human diploid fibroblast cells (HDF); Sp1 overexpression induced those genes in senescent cells. In addition, epidermal growth factor stimulation-induced p-ERK1/2 nuclear translocation and Elk-1 phosphorylation were severely impaired by Sp1 depletion in young HDFs; Sp1 overexpression restored the nuclear translocation of p-ERK1/2 in senescent HDFs. Furthermore, we observed that Sp1 protein levels were decreased in senescent cells, and H(2) O(2) treatment decreased Sp1 levels in a proteasome-dependent manner. In addition, O-GlcNAcylation of Sp1 was decreased in senescent cells as well as in H(2) O(2) -treated cells. Taken together, these results suggest that Sp1 could be a key regulator in the control of NCT genes and that reactive oxygen species-mediated alteration in Sp1 stability may be responsible for the generalized repression of those genes, leading to formation of the senescence-dependent functional nuclear barrier, resulting in subsequent hyporesponsiveness to external signals. PMID:23013401

Kim, Sung Y; Kang, Hyun T; Han, Jeong A; Park, Sang C

2012-10-19

9

Transcription factor Sp3 antagonizes activation of the ornithine decarboxylase promoter by Sp1.  

PubMed Central

Ornithine decarboxylase (ODC) expression is important for proliferation and is elevated in many tumor cells. We previously showed that Sp1 is a major positive regulator of ODC transcription. In this paper we have investigated transcriptional regulation of rat ODC by the closely related factor Sp3. While over-expression of Sp1 caused a dramatic activation of the ODC promoter, over-expression of Sp3 caused little or no activation in either Drosophila SL2 cells (lacking endogenous Sp1 or Sp3) or in H35 rat hepatoma cells. Furthermore, co-transfection studies demonstrated that Sp3 abolished trans -activation of the ODC promoter by Sp1. DNase I footprint studies and electrophoretic mobility shift assays demonstrated that both recombinant Sp1 and Sp3 bind specifically to several sites within the ODC promoter also protected by nuclear extracts, including overlapping GC and CT motifs located between -116 and -104. This CT element is a site of negative ODC regulation. Mutation of either element reduced binding, but mutation of both sites was required to eliminate binding of either Sp1 or Sp3. These results demonstrate that ODC is positively regulated by Sp1 and negatively regulated by Sp3, suggesting that the ratio of these transcription factors may be an important determinant of ODC expression during development or transformation.

Kumar, A P; Butler, A P

1997-01-01

10

Gut-enriched Kr?ppel-like factor represses cyclin D1 promoter activity through Sp1 motif  

PubMed Central

Cancer cells differ from normal cells in many characteristics including loss of differentiation and uninhibited cell proliferation. Recent studies have focused on the identification of factors contributing to cell growth and differentiation. Gut-enriched Krüppel-like factor (GKLF or KLF4) is a newly identified eukaryotic transcription factor and has been shown to play a role in regulating growth arrest. We have previously shown that GKLF mRNA levels were significantly decreased in colon cancer tissues, and that overexpression of GKLF in colonic adenocarcinoma cells (HT-29) resulted in reduction of cyclin D1 (CD1) mRNA and protein levels. The current study was undertaken to determine the mechanisms by which GKLF inhibited CD1 expression. In a transient transfection system, GKLF suppressed CD1 promoter activity by 55%. Sequential deletion and site-directed mutation analysis of the CD1 promoter have identified the sequence between –141 and –66, a region containing an Sp1 response element, to be essential for GKLF function. By electrophoretic mobility gel shift assay, recombinant GKLF and nuclear extracts from HT-29 cells were found to bind to the Sp1 motif on the CD1 promoter. The inhibitory effect of GKLF on the CD1 promoter activity was completely abolished by excessive amount of Sp1 DNA and GKLF significantly reduced the stimulatory function of Sp1 suggesting that GKLF and Sp1 may compete for the same binding site on the CD1 promoter. These results indicate that GKLF is a transcriptional repressor of the CD1 gene and that the inhibitory effect of GKLF is, in part, mediated by interaction with the Sp1 binding domain on its promoter.

Shie, Jue-Lon; Chen, Zhi Y.; Fu, Maofu; Pestell, Richard G.; Tseng, Chi-Chuan

2000-01-01

11

Transcription Factor Sp1 Is Essential for Early Embryonic Development but Dispensable for Cell Growth and Differentiation  

Microsoft Academic Search

Transcription factor Sp1 has been implicated in the expression of many genes. Moreover, it has been suggested that Sp1 is linked to the maintenance of methylation-free CpG islands, the cell cycle, and the formation of active chromatin structures. We have inactivated the mouse Sp1 gene. Sp1?\\/? embryos are retarded in development, show a broad range of abnormalities, and die around

Marisol Marin; Alar Karis; Pim Visser; Frank Grosveld; Sjaak Philipsen

1997-01-01

12

Zinc finger transcription factor Zn3-Sp1 reactions with Cd2+.  

PubMed

Cadmium is a major environmental pollutant that causes kidney failure including the inability to resorb nutrients such as glucose. In a mouse kidney cell culture model, Cd(2+) inhibits Na(+)-dependent glucose uptake mediated by SGLT transporters. This defect has been traced to the down-regulation of SGLT mRNA synthesis mediated by the zinc-finger transcription factor, Zn(3)-Sp1. Incubation of Cd(2+) with Zn(2+)-Sp1 inhibited its capacity to bind to GC1, its binding site in the SGLT1 promoter. The extent of reaction was reduced as increasing concentrations of Zn(2+) are simultaneously present in the reaction mixture. The results are consistent with a Cd(2+)-Zn(2+) exchange reaction that inactivates the DNA binding function of the protein. The equilibrium constant for this reaction was calculated as 14 +/- 3 and 7 +/- 4 for the reactions measured by the binding to GC1 and an analogous SGLT2 promoter site. Sequential addition of Cd(2+) and Zn(2+) to Zn(3)-Sp1 failed to inhibit the reduction in DNA binding seen with Cd(2+) alone, indicating that substitution of Zn(2+) by Cd(2+) was followed by a second reaction that failed to respond to Zn(2+). Buffers for the DNA binding reaction (electrophoretic mobility shift assay) contain EDTA and Cd-EDTA is active in the same concentration range as Cd(2+). During the standard 15 min incubation, Cd(2+) down-regulates Zn(3)-Sp1 but is inactive against the adduct, Zn(3)-Sp1.GC1. Kinetic studies demonstrated that with 5 muM Cd(2+), Zn(3)-Sp1 was about 75% inactivated in 15 min, whereas, Zn(3)-Sp1.GC1 was slowly dissociated with 50% still remaining after 60 min. In contrast, Zn(3)-Sp1 bound to a cognate consensus site resisted any reaction over 60 min. An adduct of Zn(3)-Sp1.(polydI-dC) was just as reactive with Cd(2+) as Zn(3)-Sp1. Reexamination of the NMR structure of Zn- and Cd-finger peptides related to Sp1 fingers has revealed subtle changes in conformation of the metalbinding site and DNA-binding helix that occur when Cd(2+) is substituted by Zn(2+). PMID:20073493

Kothinti, Rajendra; Blodgett, Amy; Tabatabai, Niloofar M; Petering, David H

2010-02-15

13

Transforming Growth Factor ? Signaling Upregulates the Expression of Human GDP-Fucose Transporter by Activating Transcription Factor Sp1.  

PubMed

GDP-fucose transporter plays a crucial role in fucosylation of glycoproteins by providing activated fucose donor, GDP-fucose, for fucosyltransferases in the lumen of the Golgi apparatus. Fucose-containing glycans are involved in many biological processes, which are essential for growth and development. Mutations in the GDP-fucose transporter gene cause leukocyte adhesion deficiency syndrome II, a disease characterized by slow growth, mental retardation and immunodeficiency. However, no information is available regarding its transcriptional regulation. Here, by using human cells, we show that TGF-?1 specifically induces the GDP-fucose transporter expression, but not other transporters tested such as CMP-sialic acid transporter, suggesting a diversity of regulatory pathways for the expression of these transporters. The regulatory elements that are responsive to the TGF-?1 stimulation are present in the region between bp -330 and -268 in the GDP-fucose transporter promoter. We found that this region contains two identical octamer GC-rich motifs (GGGGCGTG) that were demonstrated to be essential for the transporter expression. We also show that the transcription factor Sp1 specifically binds to the GC-rich motifs in vitro and Sp1 coupled with phospho-Smad2 is associated with the promoter region covering the Sp1-binding motifs in vivo using chromatin immunoprecipitation (ChIP) assays. In addition, we further confirmed that Sp1 is essential for the GDP-fucose transporter expression stimulated by TGF-?1 using a luciferase reporter system. These results highlight the role of TGF-? signaling in regulation of the GDP-fucose transporter expression via activating Sp1. This is the first transcriptional study for any nucleotide sugar transporters that have been identified so far. Notably, TGF-?1 receptor itself is known to be modified by fucosylation. Given the essential role of GDP-fucose transporter in fucosylation, the finding that TGF-?1 stimulates the expression of this transporter, suggests a possible intracellular link between the function of nucleotide sugar transporter and the TGF-? signaling pathway. PMID:24069312

Xu, Yu-Xin; Ma, Anna; Liu, Li

2013-09-12

14

Transforming Growth Factor ? Signaling Upregulates the Expression of Human GDP-Fucose Transporter by Activating Transcription Factor Sp1  

PubMed Central

GDP-fucose transporter plays a crucial role in fucosylation of glycoproteins by providing activated fucose donor, GDP-fucose, for fucosyltransferases in the lumen of the Golgi apparatus. Fucose-containing glycans are involved in many biological processes, which are essential for growth and development. Mutations in the GDP-fucose transporter gene cause leukocyte adhesion deficiency syndrome II, a disease characterized by slow growth, mental retardation and immunodeficiency. However, no information is available regarding its transcriptional regulation. Here, by using human cells, we show that TGF-?1 specifically induces the GDP-fucose transporter expression, but not other transporters tested such as CMP-sialic acid transporter, suggesting a diversity of regulatory pathways for the expression of these transporters. The regulatory elements that are responsive to the TGF-?1 stimulation are present in the region between bp ?330 and ?268 in the GDP-fucose transporter promoter. We found that this region contains two identical octamer GC-rich motifs (GGGGCGTG) that were demonstrated to be essential for the transporter expression. We also show that the transcription factor Sp1 specifically binds to the GC-rich motifs in vitro and Sp1 coupled with phospho-Smad2 is associated with the promoter region covering the Sp1-binding motifs in vivo using chromatin immunoprecipitation (ChIP) assays. In addition, we further confirmed that Sp1 is essential for the GDP-fucose transporter expression stimulated by TGF-?1 using a luciferase reporter system. These results highlight the role of TGF-? signaling in regulation of the GDP-fucose transporter expression via activating Sp1. This is the first transcriptional study for any nucleotide sugar transporters that have been identified so far. Notably, TGF-?1 receptor itself is known to be modified by fucosylation. Given the essential role of GDP-fucose transporter in fucosylation, the finding that TGF-?1 stimulates the expression of this transporter, suggests a possible intracellular link between the function of nucleotide sugar transporter and the TGF-? signaling pathway.

Xu, Yu-Xin; Ma, Anna; Liu, Li

2013-01-01

15

IL-10 gene expression is controlled by the transcription factors Sp1 and Sp3.  

PubMed

IL-10 is an 18-kDa cytokine with a key role in homeostatic control of inflammatory and immune responses. We have investigated how transcription of the IL-10 gene is regulated, so as to be able to understand the circumstances of IL-10 expression in both health and disease. In the mouse, IL-10 gene expression is regulated by a TATA-type promoter with a critical cis-acting element containing GGA repeats located at -89 to -77. Its complementary sequence is similar to the cis-acting elements (TCC repeats) in the promoters of genes encoding epidermal growth factor receptor and CD58. All these elements comprise a common CCTCCT sequence with less conserved C + T-rich sequences. Eliminating this CCTCCT sequence results in a marked reduction in promoter activity, suggesting a necessary role in IL-10 gene expression. Despite its dissimilarity to the G + C-rich Sp1 consensus sequence (GC box), Sp1 and Sp3 transcription factors could be shown to bind to this motif. The requirement for Sp1 and Sp3 in transcription of IL-10 was confirmed using Drosophila SL2 cells, which lack endogenous Sp factors. These results suggest that the transcription of IL-10 is positively regulated by both Sp1 and Sp3. PMID:10861063

Tone, M; Powell, M J; Tone, Y; Thompson, S A; Waldmann, H

2000-07-01

16

Measurement of the binding of transcription factor Sp1 to a single GC box recognition sequence.  

PubMed Central

The equilibrium constant was determined for the binding of the transcription factor Sp1 to a single consensus GC box DNA recognition site, (5'-GGGGCGGGGC-3'). For these experiments, single copies of the recognition site were synthesized and cloned in a standard plasmid background. Binding was measured either by a footprinting assay modified so that the binding reaction was at equilibrium, or by a gel mobility shift assay. The concentration of active Sp1 in the reactions and the dissociation constant were determined by computer-assisted fitting to theoretical curves. Values for the dissociation constant obtained in different experiments ranged from 4.1 X 10(-10) M to 5.3 X 10(-10) M. Several variants of the consensus recognition site were also tested. An A-substituted variant (5'-GGGGAGGGGC-3') and a T-substituted variant (5'-GGGGTGGGGC-3') were bound 3-fold and 6-fold more weakly than the consensus site, respectively. A G-substituted variant (5'-GGGGGGGGGC-3') was bound at least 30-fold more weakly than the consensus site. These findings help distinguish between alternative models for Sp1-DNA recognition. They are consistent with the presence of specific hydrogen-bond contacts between Sp1 and the central C-G base pair, but provide no particular evidence to support a model where local DNA structure is the dominant factor in the interaction. Images

Letovsky, J; Dynan, W S

1989-01-01

17

Androgen up-regulates vascular endothelial growth factor expression in prostate cancer cells via an Sp1 binding site  

PubMed Central

Background Vascular Endothelial Growth Factor (VEGF) is regulated by a number of different factors, but the mechanism(s) behind androgen-mediated regulation of VEGF in prostate cancer are poorly understood. Results Three novel androgen receptor (AR) binding sites were discovered in the VEGF promoter and in vivo binding of AR to these sites was demonstrated by chromatin immunoprecipitation. Mutation of these sites attenuated activation of the VEGF promoter by the androgen analog, R1881 in prostate cancer cells. The transcription factors AR and Sp1 were shown to form a nuclear complex and both bound the VEGF core promoter in chromatin of hormone treated CWR22Rv1 prostate cancer cells. The importance of the Sp1 binding site in hormone mediated activation of VEGF expression was demonstrated by site directed mutagenesis. Mutation of a critical Sp1 binding site (Sp1.4) in the VEGF core promoter region prevented activation by androgen. Similarly, suppression of Sp1 binding by Mithramycin A treatment significantly reduced VEGF expression. Conclusions Our mechanistic study of androgen mediated induction of VEGF expression in prostate cancer cells revealed for the first time that this induction is mediated through the core promoter region and is dependent upon a critical Sp1 binding site. The importance of Sp1 binding suggests that therapy targeting the AR-Sp1 complex may dampen VEGF induced angiogenesis and, thereby, block prostate cancer progression, helping to maintain the indolent form of prostate cancer.

2013-01-01

18

Specificity of transcriptional regulation by the zinc finger transcription factors Sp1, Sp3, and Egr-1.  

PubMed

The transcription factors Sp1, Sp3, and Egr-1 bind with their zinc finger DNA-binding domains to GC-rich sequences in the regulatory regions of their target genes. The similarity of the DNA-binding sites of Sp1, Sp3, and Egr-1 has triggered the hypothesis that they compete for the same DNA-binding site. We have investigated the specificity of transcriptional regulation by Sp1, Sp3, and Egr-1 using dominant-negative mutants that block the DNA-binding site of Sp1, Sp3, or Egr-1, respectively. The results show that constitutive transcription of Sp1 regulated reporter genes, containing Sp1 sites derived from the aldolase C and p21WAF1/Cip1 genes, or the long terminal repeat of HIV-1, was impaired by dominant-negative mutants of Sp1 and Sp3, but not by a dominant-negative Egr-1. Transcription mediated by Egr-1 was induced by transfection of expression vectors encoding wild-type or mutated Egr-1 or by stimulation of the extracellular signal-regulated protein kinase pathway via an inducible B-Raf-estrogen receptor fusion protein. In all cases transcription of Egr-1-regulated reporter genes, containing Egr-1 binding sites derived from the Egr-1 or the synapsin I gene was impaired by a dominant-negative Egr-1, but not by dominant-negative Sp1 or Sp3 mutants. These results show that there are genuine Sp1/Sp3 or Egr-1 controlled genes showing no cross-regulation of Sp1/Sp3 and Egr-1 through the same DNA-binding site. This does not exclude the existence of composite Sp1/Sp3/Egr-1 binding sites, where competition for a common DNA-binding site occurs. PMID:15523672

Al-Sarraj, Alia; Day, Regina M; Thiel, Gerald

2005-01-01

19

Reduced expression of SP1 and SP4 transcription factors in peripheral blood mononuclear cells in first-episode psychosis.  

PubMed

Alterations of transcription factor specificity protein 4 (SP4) and 1 (SP1) have been linked to different neuropsychiatric diseases. Reduced SP4 and SP1 protein levels in the prefrontal cortex have been associated with bipolar disorder and schizophrenia, respectively, suggesting that both factors could be involved in the pathogenesis of disorders with psychotic features. The aim of this study was to investigate whether the reduction of SP1, SP4 and SP3 protein and mRNA expression in peripheral blood mononuclear cells in the early stages of psychosis may act as a potential biomarker of these disorders. A cross-sectional study of first-episode psychosis patients (n = 14) compared to gender- and age-matched healthy controls (n = 14) was designed. Patients were recruited through the adult mental health services of Parc Sanitari Sant Joan de Déu. Protein and gene expression levels of SP1, SP4 and SP3 were assessed in peripheral blood mononuclear cells of patients with first-episode psychosis and healthy control subjects. We report that protein levels of SP1 and SP4, but not SP3, are significantly reduced in patients compared to controls. In contrast, we did not observe any differences in expression levels for SP1, SP4 or SP3 genes between patient and control groups. In patients, SP4 protein levels were significantly associated with SP1 protein levels. No association was found, however, between protein and gene expression levels for each factor. Our study shows reduced SP1 and SP4 protein levels in first-episode psychosis in lymphocytes, suggesting that these transcription factors are potential peripheral biomarkers of psychotic spectrum disorders in the early stages. PMID:23941741

Fusté, Montserrat; Pinacho, Raquel; Meléndez-Pérez, Iria; Villalmanzo, Núria; Villalta-Gil, Victoria; Haro, Josep Maria; Ramos, Belén

2013-08-12

20

The chum salmon insulin-like growth factor II promoter requires Sp1 for its activation by C/EBPbeta.  

PubMed

The chum salmon insulin-like growth factor II (IGF-II) gene is highly expressed in liver tissue. In this study we demonstrate that two transcription factors, Sp1 and C/EBPbeta, are involved in the enhanced expression of the salmon IGF-II gene. The presence of the fish homolog for C/EBPbeta in salmon liver RNA was confirmed by Northern blotting. The sIGF-II promoter was activated up to 20-fold by co-transfection with C/EBPbeta. The functional importance of four out of the five putative C/EBPbeta binding sites was demonstrated with mutational analysis in transient transfection assays. The transcription factor Sp1 binds to two sites within the salmon IGF-II promoter. Interestingly, mutation of the Sp1 binding sites decreases not only the basal IGF-II promoter activity but also the C/EBPbeta-induced transactivation. These results demonstrate that liver-enriched C/EBPbeta and ubiquitously expressed Sp1 each activate the sIGF-II promoter and that Sp1 is required for full transactivation of the sIGF-II gene by C/EBPbeta. This suggests that C/EBPbeta and Sp1 act in synergy. PMID:11165040

Palamarchuk, A Y; Kavsan, V M; Sussenbach, J S; Holthuizen, P E

2001-02-14

21

Cellular Transcription Factor Sp1 Recruits Simian Virus 40 Capsid Proteins to the Viral Packaging Signal, ses  

PubMed Central

Simian virus 40 (SV40) capsid assembly occurs in the nucleus. All three capsid proteins bind DNA nonspecifically, raising the dilemma of how they attain specificity to the SV40 minichromosome in the presence of a large excess of genomic DNA. The SV40 packaging signal, ses, which is required for assembly, is composed of multiple DNA elements that bind transcription factor Sp1. Our previous studies showed that Sp1 participates in SV40 assembly and that it cooperates in DNA binding with VP2/3. We hypothesized that Sp1 recruits the capsid proteins to the viral minichromosome, conferring upon them specific DNA recognition. Here, we have tested the hypothesis. Computer analysis showed that the combination of six tandem GC boxes at ses is not found at cellular promoters and therefore is unique to SV40. Cooperativity in DNA binding between Sp1 and VP2/3 was not abolished at even a 1,000-fold excess of cellular DNA, providing strong support for the recruitment hypothesis. Sp1 also binds VP1 and cooperates with VP1 in DNA binding. VP1 pentamers (VP15) avidly interact with VP2/3, utilizing the same VP2/3 domain as described for polyomavirus. We conclude that VP15-VP2/3 building blocks are recruited by Sp1 to ses, where they form the nucleation center for capsid assembly. By this mechanism the virus ensures that capsid formation is initiated at a single site around its minichromosome. Sp1 enhances the formation of SV40 pseudovirions in vitro, providing additional support for the model. Analyses of Sp1 and VP3 deletion mutants showed that Sp1 and VP2/3 bind one another and cooperate in DNA binding through their DNA-binding domains, with additional contacts outside these domains. VP1 contacts Sp1 at residues outside the Sp1 DNA-binding domain. These and additional data allowed us to propose a molecular model for the VP15-VP2/3-DNA-Sp1 complex.

Gordon-Shaag, Ariela; Ben-Nun-Shaul, Orly; Roitman, Vered; Yosef, Yael; Oppenheim, Ariella

2002-01-01

22

Transcriptional Activation of TINF2, a Gene Encoding the Telomere-Associated Protein TIN2, by Sp1 and NF-?B Factors  

PubMed Central

The expression of the telomere-associated protein TIN2 has been shown to be essential for early embryonic development in mice and for development of a variety of human malignancies. Recently, germ-line mutations in TINF2, which encodes for the TIN2 protein, have been identified in a number of patients with bone-marrow failure syndromes. Yet, the molecular mechanisms that regulate TINF2 expression are largely unknown. To elucidate the mechanisms involved in human TINF2 regulation, we cloned a 2.7 kb genomic DNA fragment containing the putative promoter region and, through deletion analysis, identified a 406 bp region that functions as a minimal promoter. This promoter proximal region is predicted to contain several putative Sp1 and NF-?B binding sites based on bioinformatic analysis. Direct binding of the Sp1 and NF-?B transcription factors to the TIN2 promoter sequence was demonstrated by electrophoretic mobility shift assay (EMSA) and/or chromatin immunoprecipitation (ChIP) assays. Transfection of a plasmid carrying the Sp1 transcription factor into Sp-deficient SL2 cells strongly activated TIN2 promoter-driven luciferase reporter expression. Similarly, the NF-?B molecules p50 and p65 were found to strongly activate luciferase expression in NF-?B knockout MEFs. Mutating the predicted transcription factor binding sites effectively reduced TIN2 promoter activity. Various known chemical inhibitors of Sp1 and NF-?B could also strongly inhibit TIN2 transcriptional activity. Collectively, our results demonstrate the important roles that Sp1 and NF-?B play in regulating the expression of the human telomere-binding protein TIN2, which can shed important light on its possible role in causing various forms of human diseases and cancers.

Kumar, Naveen; Song, Kui; Ly, Hinh

2011-01-01

23

Thyroid transcription factor-1 (TTF-1) gene: identification of ZBP-89, Sp1, and TTF-1 sites in the promoter and regulation by TNF-? in lung epithelial cells  

PubMed Central

Thyroid transcription factor-1 (TTF-1/Nkx2.1/TITF1) is a homeodomain-containing transcription factor essential for the morphogenesis and differentiation of the lung. In the lung, TTF-1 controls the expression of surfactant proteins that are essential for lung stability and lung host defense. In this study, we identified functionally important transcription factor binding sites in the TTF-1 proximal promoter and studied tumor necrosis factor-? (TNF-?) regulation of TTF-1 expression. TNF-?, a proinflammatory cytokine, has been implicated in the pathogenesis of acute respiratory distress syndrome (ARDS) and inhibits surfactant protein levels. Deletion analysis of TTF-1 5?-flanking DNA indicated that the TTF-1 proximal promoter retained high-level activity. Electrophoretic mobility shift assay, chromatin immunoprecipitation, and mutational analysis experiments identified functional ZBP-89, Sp1, Sp3, and TTF-1 sites in the TTF-1 proximal promoter. TNF-? inhibited TTF-1 protein levels in H441 and primary alveolar type II cells. TNF-? inhibited TTF-1 gene transcription and promoter activity, indicating that transcriptional mechanisms play important roles in the inhibition of TTF-1 levels. TNF-? inhibited TTF-1 but not Sp1 or hepatocyte nuclear factor-3 DNA binding to TTF-1 promoter. Transactivation experiments in A549 cells indicated that TNF-? inhibited TTF-1 promoter activation by exogenous Sp1 and TTF-1 without altering their levels, suggesting inhibition of transcriptional activities of these proteins. TNF-? inhibition of TTF-1 expression was associated with increased threonine, but not serine, phosphorylation of Sp1. Because TTF-1 serves as a positive regulator for surfactant protein gene expression, TNF-? inhibition of TTF-1 expression could have important implications for the reduction of surfactant protein levels in diseases such as ARDS.

Das, Aparajita; Acharya, Sunil; Gottipati, Koteswara Rao; McKnight, James B.; Chandru, Hemakumar; Alcorn, Joseph L.

2011-01-01

24

An Sp1 transcription factor coordinates caspase-dependent and -independent apoptotic pathways.  

PubMed

During animal development, the proper regulation of apoptosis requires the precise spatial and temporal execution of cell-death programs, which can include both caspase-dependent and caspase-independent pathways. Although the mechanisms of caspase-dependent and -independent cell killing have been examined extensively, how these pathways are coordinated within a single cell that is fated to die is unknown. Here we show that the Caenorhabditis elegans Sp1 transcription factor SPTF-3 specifies the programmed cell deaths of at least two cells-the sisters of the pharyngeal M4 motor neuron and the AQR sensory neuron-by transcriptionally activating both caspase-dependent and -independent apoptotic pathways. SPTF-3 directly drives the transcription of the gene egl-1, which encodes a BH3-only protein that promotes apoptosis through the activation of the CED-3 caspase. In addition, SPTF-3 directly drives the transcription of the AMP-activated protein kinase-related gene pig-1, which encodes a protein kinase and functions in apoptosis of the M4 sister and AQR sister independently of the pathway that activates CED-3 (refs 4, 5). Thus, a single transcription factor controls two distinct cell-killing programs that act in parallel to drive apoptosis. Our findings reveal a bivalent regulatory node for caspase-dependent and -independent pathways in the regulation of cell-type-specific apoptosis. We propose that such nodes might act as features of a general mechanism for regulating cell-type-specific apoptosis and could be therapeutic targets for diseases involving the dysregulation of apoptosis through multiple cell-killing mechanisms. PMID:23851392

Hirose, Takashi; Horvitz, H Robert

2013-07-14

25

Neuron-restrictive silencer factor functions to suppress Sp1-mediated transactivation of human secretin receptor gene.  

PubMed

In the present study, a functional neuron restrictive silencer element (NRSE) was initially identified in the 5' flanking region (-83 to -67, relative to ATG) of human secretin receptor (hSCTR) gene by promoter assays coupled with scanning mutation analyses. The interaction of neuron restrictive silencer factor (NRSF) with this motif was later indicated via gel mobility shift and ChIP assays. The silencing activity of NRSF was confirmed by over-expression and also by shRNA knock-down of endogenous NRSF. These studies showed an inverse relationship between the expression levels of NRSF and hSCTR in the cells. As hSCTR gene was previously shown to be controlled by two GC-boxes which are regulated by the ratio of Sp1 to Sp3, in the present study, the functional interactions of NRSF and Sp proteins to regulate hSCTR gene was investigated. By co-immunoprecipitation assays, we found that NRSF could be co-precipitated with Sp1 as well as Sp3 in PANC-1 cells. Interestingly, co-expressions of these factors showed that NRSF could suppress Sp1-mediated, but not Sp3-mediated, transactivation of hSCTR. Taken together, we propose here that the down-regulatory effects of NRSF on hSCTR gene expression are mediated via its suppression on Sp1-mediated transactivation. PMID:23168245

Yuan, Yuan; Chow, Billy K C; Lee, Vien H Y; Lee, Leo T O

2012-11-17

26

Functional interaction between c-Jun and promoter factor Sp1 in epidermal growth factor-induced gene expression of human 12(S)-lipoxygenase  

PubMed Central

The functional role of the interaction between c-Jun and simian virus 40 promoter factor 1 (Sp1) in epidermal growth factor (EGF)-induced expression of 12(S)-lipoxygenase gene in human epidermoid carcinoma A431 cells was studied. Coimmunoprecipitation experiments indicated that EGF stimulated interaction between c-Jun and Sp1 in a time-dependent manner. Overexpression of Ha-ras and c-Jun also enhanced the amount of c-Jun binding to Sp1. In addition, the c-Jun dominant negative mutant TAM-67 not only inhibited the coimmunoprecipitated c-Jun binding to Sp1 in a dose-dependent manner in cells overexpressing c-Jun but also reduced promoter activity of the 12(S)-lipoxygenase gene induced by c-Jun overexpression. Treatment of cells with EGF increased the interaction between the Sp1 oligonucleotide and nuclear c-Jun/Sp1 in a time-dependent manner. Furthermore, EGF activated the chimeric promoter consisting of 10 tandem GAL4-binding sites, which replaced the three Sp1-binding sites in the 12(S)lipoxygenase promoter only when coexpressed with GAL4-c-Jun () fusion proteins. These results indicate that the direct interaction between c-Jun and Sp1 induced by EGF cooperatively activated expression of the 12(S)-lipoxygenase gene, and that Sp1 may serve at least in part as a carrier bringing c-Jun to the promoter, thus transactivating the transcriptional activity of 12(S)-lipoxygenase gene.

Chen, Ben-Kuen; Chang, Wen-Chang

2000-01-01

27

Transcription Factor E2F-Associated Phosphoprotein (EAPP), RAM2/CDCA7L/JPO2 (R1), and Simian Virus 40 Promoter Factor 1 (Sp1) Cooperatively Regulate Glucocorticoid Activation of Monoamine Oxidase B  

PubMed Central

Glucocorticoid steroid hormones play important roles in many neurophysiological processes such as responses to stress, behavioral adaption, and mood. One mechanism by which glucocorticoids exert functions in the brain is via the modulation of neurotransmission systems. Glucocorticoids are capable of inducing the activities of monoamine oxidases (MAOs), which degrade monoamine neurotransmitters including serotonin, norepinephrine, phenylethylamine, and dopamine. However, the molecular mechanisms for such induction are not yet fully understood. Here, we report that dexamethasone, a synthetic glucocorticoid hormone, stimulates MAO B (an isoform of MAOs) promoter and catalytic activities via both the fourth glucocorticoid response element (GRE) and simian virus 40 promoter factor 1 (Sp1) binding sites in MAO B promoter. Electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation analysis demonstrated that glucocorticoid receptor binds to the fourth GRE in vitro and in vivo. Using Sp1-binding motifs as bait in a yeast one-hybrid system, we identified two novel transcriptional repressors of MAO B, E2F-associated phosphoprotein (EAPP) and R1 (RAM2/CDCA7L/JPO2), that down-regulate MAO B via MAO B core promoter, which contains Sp1 sites. EMSA suggested that EAPP and R1 competed with Sp1 for binding to the Sp1 site in vitro. Moreover, EAPP and R1 reduced Sp1-activated glucocorticoid activation of MAO B promoter. In response to dexamethasone, lower occupancy by EAPP and R1 and higher occupancy by Sp1 were shown at the natural MAO B core promoter. Together, this study uncovers for the first time the molecular mechanisms for glucocorticoid activation of MAO B gene and provides new insights into the hormonal regulation of MAO.

Chen, Kevin; Ou, Xiao-Ming; Wu, Jason Boyang

2011-01-01

28

Interaction of transcription factor Sp1 with the promoter of the gene for the multifunctional protein disulphide isomerase polypeptide.  

PubMed Central

Protein disulphide isomerase (PDI) is a unique polypeptide which resides in the lumen of the endoplasmic reticulum and also functions as the beta-subunit of prolyl 4-hydroxylase, as a cellular thyroid hormone-binding protein, as the smaller subunit of the microsomal triacylglycerol transfer protein complex, as a dehydroascorbate reductase and as a protein that binds various peptides in a specific manner. We have recently demonstrated that the promoter of the PDI gene contains six CCAAT boxes and other elements which are needed for efficient transcription. We now demonstrate that purified human recombinant transcription factor Sp1 interacts with two perfect GGGCGG sequences and three other GC-rich elements of the PDI promoter. Sp1 also appears to participate in the regulation of PDI gene expression, since overexpression of Sp1 stimulated PDI promoter activity in HeLa cells and mutations introduced into each of these Sp1-binding sites separately reduced the promoter strength, although even the largest decrease was only about 50%. These results support our view that expression of the gene for this polypeptide with multiple functions is secured by several regulatory elements, some of which are functionally redundant. Images Figure 2

Tasanen, K; Oikarinen, J; Kivirikko, K I; Pihlajaniemi, T

1993-01-01

29

Neu Differentiation Factor Stimulates Phosphorylation and Activation of the Sp1 Transcription Factor  

Microsoft Academic Search

Neu differentiation factors (NDFs), or neuregulins, are epidermal growth factor-like growth factors which bind to two tyrosine kinase receptors, ErbB-3 and ErbB-4. The transcription of several genes is regulated by neuregulins, including genes encoding specific subunits of the acetylcholine receptor at the neuromuscular junction. Here, we have examined the promoter of the acetylcholine receptor « subunit and delineated a minimal

IRIS ALROY; LIOR SOUSSAN; RONY SEGER; YOSEF YARDEN

30

Tumor necrosis factor alpha induces gamma-glutamyltransferase expression via nuclear factor-kappaB in cooperation with Sp1.  

PubMed

Gamma-glutamyltransferase (GGT) cleaves the gamma-glutamyl moiety of glutathione (GSH), an endogenous antioxidant, and is involved in mercapturic acid metabolism and in cancer drug resistance when overexpressed. Moreover, GGT converts leukotriene (LT) C4 into LTD4 implicated in various inflammatory pathologies. So far the effect of inflammatory stimuli on regulation of GGT expression and activity remained to be addressed. We found that the proinflammatory cytokine tumor necrosis factor alpha (TNFalpha) induced GGT promoter transactivation, mRNA and protein synthesis, as well as enzymatic activity. Remicade, a clinically used anti-TNFalpha antibody, small interfering RNA (siRNA) against p50 and p65 nuclear factor-kappaB (NF-kappaB) isoforms, curcumin, a well characterized natural NF-kappaB inhibitor, as well as a dominant negative inhibitor of kappaB alpha (IkappaBalpha), prevented GGT activation at various levels, illustrating the involvement of this signaling pathway in TNFalpha-induced stimulation. Over-expression of receptor of TNFalpha-1 (TNFR1), TNFR-associated factor-2 (TRAF2), TNFR-1 associated death domain (TRADD), dominant negative (DN) IkappaBalpha or NF-kappaB p65 further confirmed GGT promoter activation via NF-kappaB. Linker insertion mutagenesis of 536 bp of the proximal GGT promoter revealed NF-kappaB and Sp1 binding sites at -110 and -78 relative to the transcription start site, responsible for basal GGT transcription. Mutation of the NF-kappaB site located at -110 additionally inhibited TNFalpha-induced promoter induction. Chromatin immunoprecipitation (ChIP) assays confirmed mutagenesis results and further demonstrated that TNFalpha treatment induced in vivo binding of both NF-kappaB and Sp1, explaining increased GGT expression, and led to RNA polymerase II recruitment under inflammatory conditions. PMID:18996094

Reuter, Simone; Schnekenburger, Michael; Cristofanon, Silvia; Buck, Isabelle; Teiten, Marie-Hélène; Daubeuf, Sandrine; Eifes, Serge; Dicato, Mario; Aggarwal, Bharat B; Visvikis, Athanase; Diederich, Marc

2008-10-18

31

A set of proteins interacting with transcription factor Sp1 identified in a two-hybrid screening  

Microsoft Academic Search

The two-hybrid system was used to isolate cDNA clones encoding polypeptides that interact with the N-terminal region (activation domains A, B and C) of the Sp1 transcription factor. Among the 65 collected clones, 43 contained cDNA fragments with open reading frames. They corresponded to 13 genes encoding proteins of known function and to 15 genes, the proteins of which have

Magali Gunther; Madeleine Laithier; Olivier Brison

2000-01-01

32

A critical role of Sp1 transcription factor in regulating gene expression in response to insulin and other hormones  

Microsoft Academic Search

Specificity protein 1 (Sp1) belongs to a family of ubiquitously expressed, C2H2-type zinc finger-containing DNA binding proteins that activate or repress transcription of many genes in response to physiological and pathological stimuli. There is emerging evidence to indicate that in addition to functioning as ‘housekeeping’ transcription factors, members of Sp family may be key mediators of gene expression induced by

Solomon S. Solomon; Gipsy Majumdar; Antonio Martinez-Hernandez; Rajendra Raghow

2008-01-01

33

Lipopolysaccharide-induced miR-1224 negatively regulates tumour necrosis factor-? gene expression by modulating Sp1  

PubMed Central

The innate immune response provides the initial defence mechanism against infection by other organisms. However, an excessive immune response will cause damage to host tissues. In an attempt to identify microRNAs (miRNAs) that regulate the innate immune response in inflammation and homeostasis, we examined the differential expression of miRNAs using microarray analysis in the spleens of mice injected intraperitoneally with lipopolysaccharide (LPS) and saline, respectively. Following challenge, we observed 19 miRNAs up-regulated (1·5-fold) in response to LPS. Among these miRNAs, miR-1224, whose expression level increased 5·7-fold 6 hr after LPS injection and 2·3-fold after 24 hr, was selected for further study. Tissue expression patterns showed that mouse miR-1224 is highly expressed in mouse spleen, kidney and lung. Transfection of miR-1224 mimics resulted in a decrease in basal tumour necrosis factor-? (TNF-?) promoter reporter gene activity and a down-regulation of LPS-induced TNF-? mRNA in RAW264.7 cells. With public databases of miRNA target prediction, miR-1224 was shown to bind to the 3? untranslated region (UTR) of Sp1 mRNA, whose coding product controls TNF-? expression at the transcriptional level. Furthermore, we found that in HEK-293 cells, the activity of the luciferase reporter bearing Sp1 mRNA 3? UTR was down-regulated significantly when transfected with miR-1224 mimics. After transfection of miR-1224 in RAW264.7 cells, nucleus Sp1 protein level decreased, and when endogenous miR-1224 was blocked, the decrease was abolished. Therefore, we initially speculated that miR-1224 was a negative regulator of TNF-? in an Sp1-dependent manner, which was confirmed in vivo by chromatin immunoprecipitation assay, and might be involved in regulating the LPS-mediated inflammatory responses.

Niu, Yuna; Mo, Delin; Qin, Limei; Wang, Chong; Li, Anning; Zhao, Xiao; Wang, Xiaoying; Xiao, Shuqi; Wang, Qiwei; Xie, Ying; He, Zuyong; Cong, Peiqing; Chen, Yaosheng

2011-01-01

34

Developmental activation of an episomic hsp70 gene promoter in two-cell mouse embryos by transcription factor Sp1.  

PubMed Central

To investigate the control of zygotic genome expression in two-cell mouse embryos, we studied transcription factors required for transient expression of microinjected DNA constructs driven by the promoter of one of the earliest genes activated after fertilization in this system, the heat shock gene hsp70. Cis-acting elements required for hsp70 activation were first investigated by mutational analysis. Mutation of the TATA box and a proximal GC box strongly inhibited construct expression, while that of a CCAAT box had no effect. Transcription factors binding the wild-type hsp70 promoter were then titrated in vivo by coinjecting the construct with double-stranded oligodeoxyribonucleotides containing definite consensus sequences. Wild-type GC box oligonucleotides strongly inhibited construct expression, while those containing mutated GC boxes, wild-type CCAAT boxes, and heat shock elements had no effects. Finally, construct expression was challenged by coinjecting antibodies to specific transcription factors. Antibodies to factor Sp1 depressed construct expression in a dose-dependent manner, while those to Sp2, HSF1 and HSF2 were ineffective. These results pinpoint the Sp1 transcription factor as an absolute requirement for activation of the hsp70 gene promoter in two-cell mouse embryos, and make this factor a candidate for a major regulator of the onset of murine zygotic genome expression.

Bevilacqua, A; Fiorenza, M T; Mangia, F

1997-01-01

35

Modulation of transforming growth factor beta signalling pathway genes by transforming growth factor beta in human osteoarthritic chondrocytes: involvement of Sp1 in both early and late response cells to transforming growth factor beta  

PubMed Central

Introduction Transforming growth factor beta (TGF?) plays a central role in morphogenesis, growth, and cell differentiation. This cytokine is particularly important in cartilage where it regulates cell proliferation and extracellular matrix synthesis. While the action of TGF? on chondrocyte metabolism has been extensively catalogued, the modulation of specific genes that function as mediators of TGF? signalling is poorly defined. In the current study, elements of the Smad component of the TGF? intracellular signalling system and TGF? receptors were characterised in human chondrocytes upon TGF?1 treatment. Methods Human articular chondrocytes were incubated with TGF?1. Then, mRNA and protein levels of TGF? receptors and Smads were analysed by RT-PCR and western blot analysis. The role of specific protein 1 (Sp1) was investigated by gain and loss of function (inhibitor, siRNA, expression vector). Results We showed that TGF?1 regulates mRNA levels of its own receptors, and of Smad3 and Smad7. It modulates TGF? receptors post-transcriptionally by affecting their mRNA stability, but does not change the Smad-3 and Smad-7 mRNA half-life span, suggesting a potential transcriptional effect on these genes. Moreover, the transcriptional factor Sp1, which is downregulated by TGF?1, is involved in the repression of both TGF? receptors but not in the modulation of Smad3 and Smad7. Interestingly, Sp1 ectopic expression permitted also to maintain a similar expression pattern to early response to TGF? at 24 hours of treatment. It restored the induction of Sox9 and COL2A1 and blocked the late response (repression of aggrecan, induction of COL1A1 and COL10A1). Conclusions These data help to better understand the negative feedback loop in the TGF? signalling system, and enlighten an interesting role of Sp1 to regulate TGF? response.

2011-01-01

36

The transcription factors Sp1, Sp3, and AP-2 are required for constitutive matrix metalloproteinase-2 gene expression in astroglioma cells.  

PubMed

Matrix metalloproteinases (MMPs) are zinc-dependent endopeptidases that contribute to pathological conditions associated with angiogenesis and tumor invasion. MMP-2 is highly expressed in human astroglioma cells, and contributes to the invasiveness of these cells. The human MMP-2 promoter contains potential cis-acting regulatory elements including cAMP response element-binding protein, AP-1, AP-2, PEA3, C/EBP, and Sp1. Deletion and site-directed mutagenesis analysis of the MMP-2 promoter demonstrates that the Sp1 site at -91 to -84 base pairs and the AP-2 site at -61 to -53 base pairs are critical for constitutive activity of this gene in invasive astroglioma cell lines. Electrophoretic gel shift analysis demonstrates binding of specific DNA-protein complexes to the Sp1 and AP-2 sites: Sp1 and Sp3 bind to the Sp1 site, while the AP-2 transcription factor binds the AP-2 element. Co-transfection expression experiments in Drosophilia SL2 cells lacking endogenous Sp factors demonstrate that Sp1 and Sp3 function as activators of the MMP-2 promoter and synergize for enhanced MMP-2 activation. Overexpression of AP-2 in AP-2-deficient HepG2 cells enhances MMP-2 promoter activation. These findings document the functional importance of Sp1, Sp3, and AP-2 in regulating constitutive expression of MMP-2. Delineation of MMP-2 regulation may have implications for development of new therapeutic strategies to arrest glioma invasion. PMID:10506168

Qin, H; Sun, Y; Benveniste, E N

1999-10-01

37

CpG methylation plays a vital role in determining tissue- and cell-specific expression of the human cell-death-inducing DFF45-like effector A gene through the regulation of Sp1\\/Sp3 binding  

Microsoft Academic Search

Cell-death-inducing DFF45-like effector A (CIDE-A) belongs to a family of proapoptotic proteins, the expression of which is highly restricted in human tissues and cells. Here, the core region of the human CIDE-A promoter was characterized. Surprisingly, two Sp1\\/Sp3-binding sites, rather than tissue- specific transcription factors, were found to be required for the promoter activity. Although the ubiquitously expressed Sp1 and

D. Li; L. Da; H. Tang; T. Li; M. Zhao

2007-01-01

38

Interplay of posttranslational modifications in Sp1 mediates Sp1 stability during cell cycle progression.  

PubMed

Although Sp1 is known to undergo posttranslational modifications such as phosphorylation, glycosylation, acetylation, sumoylation, and ubiquitination, little is known about the possible interplay between the different forms of Sp1 that may affect its overall levels. It is also unknown whether changes in the levels of Sp1 influence any biological cell processes. Here, we identified RNF4 as the ubiquitin E3 ligase of Sp1. From in vitro and in vivo experiments, we found that sumoylated Sp1 can recruit RNF4 as a ubiquitin E3 ligase that subjects sumoylated Sp1 to proteasomal degradation. Sp1 mapping revealed two ubiquitination-related domains: a small ubiquitin-like modifier in the N-terminus of Sp1(Lys16) and the C-terminus of Sp1 that directly interacts with RNF4. Interestingly, when Sp1 was phosphorylated at Thr739 by c-Jun NH(2)-terminal kinase 1 during mitosis, this phosphorylated form of Sp1 abolished the Sp1-RNF4 interaction. Our results show that, while sumoylated Sp1 subjects to proteasomal degradation, the phosphorylation that occurs during the cell cycle can protect Sp1 from degradation by repressing the Sp1-RNF4 interaction. Thus, we propose that the interplay between posttranslational modifications of Sp1 plays an important role in cell cycle progression and keeps Sp1 at a critical level for mitosis. PMID:21983342

Wang, Yi-Ting; Yang, Wen-Bin; Chang, Wen-Chang; Hung, Jan-Jong

2011-09-28

39

Down-regulation of human topoisomerase II? expression correlates with relative amounts of specificity factors Sp1 and Sp3 bound at proximal and distal promoter regions  

PubMed Central

Background Topoisomerase II? has been shown to be down-regulated in doxorubicin-resistant cell lines. The specificity proteins Sp1 and Sp3 have been implicated in regulation of topoisomerase II? transcription, although the mechanism by which they regulate expression is not fully understood. Sp1 has been shown to bind specifically to both proximal and distal GC elements of the human topoisomerase II? promoter in vitro, while Sp3 binds only to the distal GC element unless additional flanking sequences are included. While Sp1 is thought to be an activator of human topoisomerase II?, the functional significance of Sp3 binding is not known. Therefore, we sought to determine the functional relationship between Sp1 and Sp3 binding to the topoisomerase II? promoter in vivo. We investigated endogenous levels of Sp1, Sp3 and topoisomerase II? as well as binding of both Sp1 and Sp3 to the GC boxes of the topoisomerase II? promoter in breast cancer cell lines in vivo after short term doxorubicin exposure. Results Functional effects of Sp1 and Sp3 were studied using transient cotransfection assays using a topoisomerase II? promoter reporter construct. The in vivo interactions of Sp1 and Sp3 with the GC elements of the topoisomerase II? promoter were studied in doxorubicin-treated breast cancer cell lines using chromatin immunoprecipitation assays. Relative amounts of endogenous proteins were measured using immunoblotting. In vivo DNA looping mediated by proteins bound at the GC1 and GC2 elements was studied using the chromatin conformation capture assay. Both Sp1 and Sp3 bound to the GC1 and GC2 regions. Sp1 and Sp3 were transcriptional activators and repressors respectively, with Sp3 repression being dominant over Sp1-mediated activation. The GC1 and GC2 elements are linked in vivo to form a loop, thus bringing distal regulatory elements and their cognate transcription factors into close proximity with the transcription start site. Conclusion These observations provide a mechanistic explanation for the modulation of topoisomerase II? and concomitant down-regulation that can be mediated by topoisomerase II poisons. Competition between Sp1 and Sp3 for the same cognate DNA would result in activation or repression depending on absolute amounts of each transcription factor in cells treated with doxorubicin.

Williams, Amram O; Isaacs, Richard J; Stowell, Kathryn M

2007-01-01

40

Prostaglandin E2 induces stromal cell-derived factor-1 expression in prostate stromal cells by activating protein kinase A and transcription factor Sp1.  

PubMed

Recent reports indicate prostaglandin E2 (PGE2) can modulate tumor environment and promote angiogenesis through induction of stromal cell-derived factor 1 (SDF-1) production. We investigated the mechanism of PGE2-induced SDF-1 regulation in human prostate stromal cell and analyzed the effects in a stromal-epithelial interaction model. PGE2 stimulation increased SDF-1 expression in the prostate stromal cell lines WPMY-1 and NAF. We revealed signaling through the PGE2 receptor EP3 and activation of protein kinase A (PKA) are required. The EP3 agonist sulprostone and the cAMP analog forskolin mimicked and the EP3 siRNA, antagonist L798106 and the PKA inhibitor H89 abrogated the effect of PGE2 on SDF-1 expression. SDF-1 promoter truncation experiments demonstrated a 254 bp (from nt -219 to nt +34) SDF-1 proximal promoter fragment containing 5 putative transcription factor Sp1 binding motifs is sufficient for PGE2 induction. CHIP assays confirmed binding and PGE2 induced recruitment of Sp1 to the SDF-1 promoter. Sp1 motif mutation identified Sp1 motifs -140/-133 and -9/+1 as the crucial elements responsible for PGE2 induction. Moreover, SDF-1 was up- or down-regulated by Sp1 over-expression or knock-down. We also demonstrate stimulation of migration of prostate cancer cell lines PC3 and DU145 with conditioned media collected from WPMY-1 or NAF cells stimulated with PGE2 and blockade of enhanced migration by a SDF-1 neutralizing antibody. In conclusion, we provide evidence for a paracrine prostate stromal-epithelial interaction induced by upregulation of expression of SDF-1 by PGE2. Our research provides new insights into the mechanism promoting metastasis of prostate carcinoma via stromal-epithelial interaction. PMID:23246486

Peng, Yanfei; Shi, Jiandang; Du, Xiaoling; Wang, Liang; Klocker, Helmut; Mo, Linjian; Mo, Zengnan; Zhang, Ju

2012-12-11

41

The binding of the ubiquitous transcription factor Sp1 at the locus control region represses the expression of ?-like globin genes  

PubMed Central

To investigate the function of transcription factor Sp1 in ?-like globin gene activation, we analyzed the recruitment of Sp1, fetal Krüppel-like factor 2 (FKLF2), and related factors at the human ?-globin locus in a human fetal liver and mouse erythroleukemia hybrid cell (A181? cell) that contains a single copy of human chromosome 11. Sp1 binds at the GT boxes of the cis-elements throughout the ?-locus, but it is phosphorylated and lost over DNase I hypersensitive site (HS)2, HS3, HS4, and the human ?-globin gene promoter after A181? cell differentiation. The binding of FKLF2 at HS2 and HS3 was unchanged. Histone deacetylase 1, which could be recruited by Sp1, is also lost over HS2 and HS3 after differentiation, resulting in the acetylation of histones 3 and 4 across the human ?-globin locus. We previously detected in vivo GT footprints over the ?-globin locus after A181? differentiation. Here, we report that after differentiation, the p300/CREB-binding protein-associated factor is recruited by FKLF2 to the locus control region to acetylate histones 3 and 4 at the human ?-globin gene locus. Our results suggest that Sp1 is an inhibitor of ?-like globin gene transcription during erythroid terminal differentiation. Its phosphorylation and release allow the erythroid-specific FKLF2 or erythroid Krüppel-like factor to interact with other erythroid-specific transcription factors to initiate the transcription of ?-like globin genes.

Feng, Dongxiao; Kan, Yuet Wai

2005-01-01

42

Transcription Factor Sp1 Is Involved in Expressional Regulation of Coxsackie and Adenovirus Receptor in Cancer Cells  

PubMed Central

Coxsackie and adenovirus receptor (CAR) was first known as a virus receptor. Recently, it is also known to have tumor suppressive activity such as inhibition of cell proliferation, migration, and invasion. It is important to understand how CAR expression can be regulated in cancers. Based on an existence of putative Sp1 binding site within CAR promoter, we investigated whether indeed Sp1 is involved in the regulation of CAR expression. We observed that deletion or mutation of Sp1 binding motif (?503/?498) prominently impaired the Sp1 binding affinity and activity of CAR promoter. Histone deacetylase inhibitor (TSA) treatment enhanced recruitment of Sp1 to the CAR promoter in ChIP assay. Meanwhile, Sp1 binding inhibitor suppressed the recruitment. Exogenous expression of wild-type Sp1 increased CAR expression in CAR-negative cells; meanwhile, dominant negative Sp1 decreased the CAR expression in CAR-positive cells. These results indicate that Sp1 is involved in regulation of CAR expression.

Chung, Sun-Ku; Kim, Joo-Young; Lim, Joong-Yeon; Park, Young Mi; Hwang, Ha-Young; Nam, Jae-Hwan; Park, Sang Ick

2011-01-01

43

Transcription factor Sp1 is important for retinoic acid-induced expression of the tissue plasminogen activator gene during F9 teratocarcinoma cell differentiation.  

PubMed Central

The induced differentiation of F9 cells by retinoic acid (RA) and cyclic AMP (cAMP) activated transcription of the tissue plasminogen activator (t-PA) gene. This differentiation-responsive regulation of the t-PA promoter was also observed in transient assays. Multiple sequence elements within 243 bp of t-PA DNA contributed to the high level of transcription in retinoic acid- and cyclic AMP-differentiated cells. To investigate the factors involved in controlling t-PA transcription upon differentiation, we used F9 cell extracts to examine proteins that bind two proximal promoter elements. These elements (boxes 4 and 5) are homologous to GC boxes that are known binding sites for transcription factor Sp1. Mobility shift assays in the presence and absence of anti-Sp1 antibodies demonstrated that the proteins which bound to this region were immunologically related to human Sp1. The proteins also had a DNA-binding specificity similar to that of a truncated form of Sp1. Mutations of the GC motif within boxes 4 and 5 that interfered with Sp1 binding reduced in parallel the binding of the F9 cellular factors and lowered transcription in vitro as well as in vivo. Although this proximal region of the t-PA promoter was active in vivo only in differentiated cells, the Sp1-like binding proteins were present in equal concentrations and had similar properties in extracts of both stem and differentiated cells. These data suggest that other cellular elements participate with this Sp1-like factor in controlling differentiation-specific expression. Images

Darrow, A L; Rickles, R J; Pecorino, L T; Strickland, S

1990-01-01

44

Novel clustering of Sp1 transcription factor binding sites at the transcription initiation site of the human muscle phosphofructokinase P1 promoter.  

PubMed Central

The regulatory sequence elements of the human muscle phosphofructokinase (HPFKM) p1 promoter from -655 to +78 were cloned and characterized. In the human cervical carcinoma cell line, HeLa S3, the HPFKM type C RNA initiated from a single predominant transcription initiation site and the HPFKM p1 promoter displayed transcriptional activity in transient transfection assays. The HPFKM p1 promoter region was shown to possess eight binding sites for the Sp1 transcription factor by DNase I footprinting and gel retardation analysis. The functional importance of these interactions was examined by transient transfection analysis in Drosophila SL2 and HeLa S3 cells. This analysis demonstrated that the HPFKM p1 promoter sequence between +12 and +78 retained Sp1-dependent transcriptional activity in Drosophila SL2 cells and retained promoter activity in HeLa S3 cells. These results suggest that the Sp1 binding site (site 8 between +12 and +21) immediately adjacent to the transcription initiation site represents an important regulatory element of this promoter at least in the context of the minimal HPFKM p1 promoter. However mutagenesis of the Sp1 site 8 demonstrated that, in the context of a larger HPFKM p1 promoter region containing Sp1 sites 1 to 7, it now contributed very little to the total promoter activity. Therefore it appears the Sp1 sites in the HPFKM p1 promoter display functional redundancy. Images

Johnson, J L; McLachlan, A

1994-01-01

45

Play Deprivation: A Factor in Juvenile Violence.  

ERIC Educational Resources Information Center

Notes that the increasing number of violent crimes committed by children is a result of play deprivation. Discusses different forms of play and distinguishes between controlled and free play. Examines factors such as inadequate outdoor spaces, organized sports, and hi-tech entertainment which interfere with spontaneous play. Discusses the concept…

Frost, Joe; Jacobs, Paul J.

1995-01-01

46

The cellular transcription factor SP1 and an unknown cellular protein are required to mediate Rep protein activation of the adeno-associated virus p19 promoter.  

PubMed Central

Control of adeno-associated virus (AAV) transcription from the three AAV promoters (p5, p19, and p40) requires the adenovirus E1a protein and the AAV nonstructural (Rep) proteins. The Rep proteins have been shown to repress the AAV p5 promoter yet facilitate activation of the p19 and p40 promoters during a productive infection. To elucidate the mechanism of promoter regulation by the AAV Rep proteins, the cellular factors involved in mediating Rep activation of the p19 promoter were characterized. A series of protein-DNA binding experiments using extracts derived from uninfected HeLa cells was performed to identify cellular factors that bind to the p19 promoter. Electrophoretic mobility shift assays, DNase I protection analyses, and UV cross-linking experiments demonstrated specific interactions with the cellular factor SP1 (or an SP1-like protein) at positions -50 and -130 relative to the start of p19 transcription. Additionally, an unknown cellular protein (cellular AAV activating protein [cAAP]) with an approximate molecular mass of 34 kDa was found to interact with a CArG-like element at position -140. Mutational analysis of the p19 promoter suggested that the SP1 site at -50 and the cAAP site at -140 were necessary to mediate Rep activation of p19. Antibody precipitation experiments demonstrated that Rep-SP1 protein complexes can exist in vivo. Although Rep was demonstrated to interact with p19 DNA directly, the affinity of Rep binding was much lower than that seen for the Rep binding elements within the terminal repeat and the p5 promoter. Furthermore, the interaction of purified Rep68 with the p19 promoter in vitro was negligible unless purified SP1 was also added to the reaction. Thus, the ability of Rep to transactivate the p19 promoter is likely to involve SP1-Rep protein contacts that facilitate Rep interaction with p19 DNA.

Pereira, D J; Muzyczka, N

1997-01-01

47

Sp1, a CAAT-binding factor, and the adenovirus major late promoter transcription factor interact with functional regions of the gamma-fibrinogen promoter.  

PubMed Central

To study the factors which influence the coordinately and developmentally regulated expression of the three adjacent fibrinogen genes, we have defined the functional regions of the gamma-fibrinogen promoter and the proteins which bind to them. Using a series of 5' and internal deletion mutations, we found that sequences between 88 and 43 base pairs (bp) upstream of the gamma-fibrinogen transcription initiation site functioned in cis to direct properly initiated mRNA accumulation in transfected hepatocytes. The efficient function of these sequences was highly distance dependent, since transcriptional activity decreased by 92% when they were moved 32 bp upstream of the TATA box. We demonstrated that two known and one putative transcriptional factors interacted with this 47-bp sequence. The transcription factor Sp1 interacted with sequences between -51 and -46 as demonstrated by protection from DNase I digestion with the purified protein. Directly adjacent to the Sp1 site, between nucleotides -66 and -53, there was a sequence which bound a CAAT-binding factor. Finally, sequences just 5' to the CAAT factor-binding site interacted with the adenovirus major late transcriptional factor as previously demonstrated. Internal deletion mutations which disrupt these interactions diminished the activity of the promoter in vivo. One consequence of the interaction of these proteins is that a bend is placed in the DNA at or near their sites of interaction. Images

Morgan, J G; Courtois, G; Fourel, G; Chodosh, L A; Campbell, L; Evans, E; Crabtree, G R

1988-01-01

48

miR-375 is down-regulated in squamous cervical cancer and inhibits cell migration and invasion via targeting transcription factor SP1.  

PubMed

Pelvic lymph node metastases are regarded as the most important risk factor and a predictor of poor prognosis for patients with cervical cancer. Exploration of metastasis-related molecules is helpful toward improving the prognosis in cervical cancer. To identify the role of miR-375 in metastasis and progression of cervical cancer, we examined the expression of miR-375 in 170 cervical cancer tissues and 68 normal cervical tissues, using stem-loop quantitative PCR, and found that the expression of miR-375 in cervical cancer tissues was significantly decreased by 4.45-fold, compared with 68 normal tissues. A significant correlation existed between miR-375 expression and clinicopathologic parameters, including lymph node metastasis of cervical cancer. Overexpressed miR-375 suppressed cell proliferation, blocked G1-to-S cell-cycle transition, and inhibited cell migration and invasion in human cervical SiHa and CaSki cells. SP1, a potential target gene of miR-375, was inversely correlated with miR-375 expression in cervical cancer tissues. Moreover, SP1 was negatively regulated by miR-375, and knockdown of SP1 by siRNA inhibited cell malignant behaviors. Thus, our findings suggest that down-regulated miR-375 promotes cell malignant behaviors via the target gene SP1 and may consequently contribute to the progression of cervical cancer. PMID:21945323

Wang, Fenfen; Li, Yang; Zhou, Jiansong; Xu, Junfen; Peng, Chanjuan; Ye, Feng; Shen, Yuanming; Lu, Weiguo; Wan, Xiaoyun; Xie, Xing

2011-09-21

49

Insulin regulates hypoxia-inducible factor-1? transcription by reactive oxygen species sensitive activation of Sp1 in 3T3-L1 preadipocyte.  

PubMed

Oxygen sensing transcription factor HIF-1 is activated due to accumulation of regulatory subunit HIF-1? by posttranslational stability mechanism during hypoxia or by several other stimuli even in normoxia. HIF-1? is also regulated by NF-kB mediated transcription mechanism. Reactive oxygen species (ROS) act as an important regulator of HIF-1 either by affecting prolyl hydroxylase activity, the critical determinant of HIF-1? stabilization or by activating NF-kB to promote HIF-1? transcription. Insulin is known to activate HIF-1 by a ROS dependent mechanism but the molecular mechanism of HIF-1? regulation is not known so far. Here we show that insulin regulates HIF-1? by a novel transcriptional mechanism by a ROS-sensitive activation of Sp1 in 3T3-L1 preadipocyte. Insulin shows little effect on HIF-1? protein stability, but increases HIF-1? promoter activity. Mutation analyses, electrophoretic mobility shift assay and chromatin immunoprecipitation assay confirm the role of Sp1 in HIF-1? transcription. We further demonstrate that insulin-induced ROS generation initiates signaling pathway involving phosphatidylinositol 3-kinase and protein kinase C for Sp1 mediated HIF-1? transcription. In summary, we reveal that insulin regulates HIF-1? by a novel transcriptional mechanism involving Sp1. PMID:23626778

Biswas, Sudipta; Mukherjee, Reshmi; Tapryal, Nisha; Singh, Amit K; Mukhopadhyay, Chinmay K

2013-04-23

50

Aristolochic acid I and ochratoxin A differentially regulate VEGF expression in porcine kidney epithelial cells--The involvement of SP-1 and HIFs transcription factors  

PubMed Central

Aristolochic acid I (AAI) and ochratoxin A (OTA) cause chronic kidney diseases. Recently, the contribution of hypoxic injuries and angiogenic disturbances to nephropathies has been suggested, but underlying mechanisms have not been fully clarified yet. In porcine kidney epithelial cell line, LLC-PK1 cells, treatment with non-toxic doses of AAI increased whereas with OTA decreased production of vascular endothelial growth factor (VEGF), the angiogenic factor with well-defined functions in kidney. Moreover, the activity of transcription factors regulating VEGF expression was differentially affected by examined compounds. Activity of hypoxia inducible factors (HIFs) and SP-1 was increased by AAI but diminished by OTA. Interestingly, AP-1 activity was inhibited while NF?B was not influenced by both toxins. Mithramycin A, a SP-1 inhibitor, as well as chetomin, an inhibitor of HIFs, reversed AAI-induced up-regulation of VEGF synthesis, indicating the importance of SP-1 and HIFs in this effect. Additionally, adenoviral overexpression of HIF-2? but not HIF-1? prevented OTA-diminished VEGF production suggesting the protective effect of this isoform towards the consequences exerted by OTA. These observations provide new insight into complex impact of AAI and OTA on angiogenic gene regulation. Additionally, it adds to our understanding of hypoxia influence on nephropathies pathology.

Stachurska, Anna; Kozakowska, Magdalena; Jozkowicz, Alicja; Dulak, Jozef; Loboda, Agnieszka

2011-01-01

51

Regulation of the Human MSH6 Gene by the Sp1 Transcription Factor and Alteration of Promoter Activity and Expression by Polymorphisms  

Microsoft Academic Search

Defects in human DNA mismatch repair have been reported to underlie a variety of hereditary and sporadic cancer cases. We characterized the structure of the MSH6 promoter region to examine the mechanisms of transcriptional regulation of the MSH6 gene. The 5-flanking region of the MSH6 gene was found to contain seven functional Sp1 transcription factor binding sites that each bind

Isabella Gazzoli; Richard D. Kolodner

2003-01-01

52

A novel cis-acting element controlling the rat CYP2D5 gene and requiring cooperativity between C/EBP beta and an Sp1 factor.  

PubMed

The rat CYP2D5 gene encodes a cytochrome P450 and is expressed in liver cells. Its expression commences a few days after birth, and maximal mRNA levels are achieved when animals reach puberty. Transfection and DNA binding studies were performed to investigate the mechanism controlling developmentally programmed, liver-specific expression of CYP2D5. Transfection studies using a series of CYP2D5 upstream DNA chloramphenicol acetyltransferase gene fusion constructs identified a segment of DNA between nucleotides -55 and -156 that conferred transcriptional activity in HepG2 cells. Activity was markedly increased by cotransfection with a vector expressing C/EBP beta but was unaffected by vectors producing other liver-enriched transcription factors (C/EBP alpha, HNF-1 alpha, and DBP). DNase I footprinting revealed a region protected by both HepG2 and liver cell nuclear extracts between nucleotides -83 and -112. This region displayed some sequence similarity to the Sp1 consensus sequence and was able to bind the Sp1 protein, as assessed by a gel mobility shift assay. The role of Sp1 in CYP2D5 transcription was confirmed by trans activation of the 2D5-CAT construct in Drosophila melanogaster cells by using an Sp1 expression vector. C/EBP beta alone was unable to directly bind the -83 to -112 region of the promoter but was able to produce a ternary complex when combined with HepG2 nuclear extracts or recombinant human Sp1. C/EBP alpha was unable to substitute for C/EBP beta in forming this ternary complex. A poor C/EBP binding site is present adjacent to the Sp1 site, and mutagenesis of this site abolished formation of the ternary complex with the CYP2D5 regulatory region. These result establish that two transcription factors can work in conjunction, possibly by protein-protein interaction, to activate the CYP2D5 gene. PMID:8289814

Lee, Y H; Yano, M; Liu, S Y; Matsunaga, E; Johnson, P F; Gonzalez, F J

1994-02-01

53

The Maternally Expressed Gene Tssc3 Regulates the Expression of MASH2 Transcription Factor in Mouse Trophoblast Stem Cells through the AKT-Sp1 Signaling Pathway*  

PubMed Central

Tssc3 is a maternally expressed/paternally silenced imprinted gene. Recent evidence suggests that the loss of TSSC3 results in placental overgrowth in mice. These findings showed that the TSSC3 gene functions as a negative regulator of placental growth. In this study, we describe the function of TSSC3 and its signaling pathway in mouse trophoblast stem (TS) cell differentiation. First of all, we tested Tssc3 expression levels in TS cells. TS cells expressed Tssc3, and its expression level was the highest from day 1 to 4 but was down-regulated at day 5 after the induction of differentiation. Overexpression of TSSC3 in TS cells up-regulated Gcm1 and Mash2, which are marker genes of mouse trophoblast differentiation. Down-regulation of TSSC3 by siRNA enhanced Pl1 and Tpbpa expression in TS cells cultured under stem cell conditions, suggesting the contribution of TSSC3 to the differentiation from TS to trophoblast progenitors and/or labyrinth trophoblasts. TSSC3 activated the PI3K/AKT pathway through binding with phosphatidylinositol phosphate lipids and enhanced the activity of a promoter containing an E-box structure, which is the binding sequence of the Mash2 downstream target gene promoter. PI3K inhibitor suppressed the promoter activity induced by TSSC3. TSSC3 induced Sp1 translocation from cytoplasm to nucleus through the PI3K/AKT pathway. Nuclear Sp1 activated the Mash2 transcription by Sp1 binding with a consensus Sp1-binding motif. This is the first report describing that TSSC3 plays an important role in the differentiation from TS to trophoblast progenitors and/or labyrinth trophoblasts through the TSSC3/PI3K/AKT/MASH2 signaling pathway.

Takao, Tomoka; Asanoma, Kazuo; Tsunematsu, Ryosuke; Kato, Kiyoko; Wake, Norio

2012-01-01

54

Arsenic trioxide-mediated growth inhibition in gallbladder carcinoma cells via down-regulation of Cyclin D1 transcription mediated by Sp1 transcription factor  

SciTech Connect

Gallbladder carcinoma (GBC), an aggressive and mostly lethal malignancy, is known to be resistant to a number of drug stimuli. Here, we demonstrated that arsenic trioxide inhibited the proliferation of gallbladder carcinoma in vivo and in vitro as well as the transcription of cell cycle-related protein Cyclin D1. And, Cyclin D1 overexpression inhibited the negative role of arsenic trioxide in cell cycle progression. We further explored the mechanisms by which arsenic trioxide affected Cyclin D1 transcription and found that the Sp1 transcription factor was down-regulated by arsenic trioxide, with a corresponding decrease in Cyclin D1 promoter activity. Taken together, these results suggested that arsenic trioxide inhibited gallbladder carcinoma cell proliferation via down-regulation of Cyclin D1 transcription in a Sp1-dependent manner, which provided a new mechanism of arsenic trioxide-involved cell proliferation and may have important therapeutic implications in gallbladder carcinoma patients.

Ai, Zhilong [Zhongshan Hospital, Fudan University, Shanghai 200032 (China); Lu, Weiqi [Zhongshan Hospital, Fudan University, Shanghai 200032 (China); Ton, Saixiong [Zhongshan Hospital, Fudan University, Shanghai 200032 (China); Liu, Houbao [Zhongshan Hospital, Fudan University, Shanghai 200032 (China); Sou, Tao [Zhongshan Hospital, Fudan University, Shanghai 200032 (China); Shen, Zhenbin [Zhongshan Hospital, Fudan University, Shanghai 200032 (China); Qin, Xinyu [Zhongshan Hospital, Fudan University, Shanghai 200032 (China)]. E-mail: smc_jjh@yahoo.com.cn

2007-08-31

55

Transcription Factors Sp1 and Sp3 Alter Vascular Endothelial Growth Factor Receptor Expression through a Novel Recognition Sequence  

Microsoft Academic Search

Kinase domain receptor (KDR) is a high affinity, en- dothelial cell-specific, autophosphorylating tyrosine ki- nase receptor for vascular endothelial growth factor. This transcriptionally regulated receptor is a critical mediator of endothelial cell (EC) growth and vascular development. In this study, we identify a DNA element modulating KDR promoter activity and evaluate the nu- clear binding proteins accounting for a portion

Yasuaki Hata; Elia Duh; Kang Zhang; Gregory S. Robinsoni; Lloyd Paul Aiello

1998-01-01

56

Reduced O glycosylation of Sp1 is associated with increased proteasome susceptibility.  

PubMed Central

Sp1 is a ubiquitously expressed transcription factor that is particularly important for the regulation of TATA-less genes that encode housekeeping proteins. Most growth factors and receptors are also encoded by such genes. Sp1 is multiply O glycosylated by covalent linkage of the monosaccharide N-acetylglucosamine (O-GlcNAc) to serine and threonine residues. Based on an earlier observation that growth factor gene transcription can be regulated by glucose and glucosamine in vascular smooth muscle cells, we determined whether Sp1 glycosylation could be regulated and if this modification altered Sp1 function. We found that Sp1 becomes hyperglycosylated when cells are exposed to 5 mM glucosamine, whereas under glucose starvation, stimulation with cyclic AMP (cAMP) results in nearly complete deglycosylation of this protein. Correlating with this hypoglycosylated state, Sp1 is rapidly proteolytically degraded by an enzyme(s) that can be inhibited by specific proteasome inhibitors, lactacystin and LLnL. Treatment of cells with glucose or glucosamine protects Sp1 from cAMP-mediated degradation, whereas blockade of glucosamine synthesis abrogates glucose but not glucosamine protection. This effect on Sp1 is specific, in that the Stat-3 and E2F transcription factors did not undergo degradation under these conditions. The O-GlcNAc modification of Sp1 may play a role as a nutritional checkpoint. In the absence of adequate nutrition, Sp1 becomes hypoglycosylated and thereby subject to proteasome degradation. This process could potentially result in reduced general transcription, thereby conserving nutrients.

Han, I; Kudlow, J E

1997-01-01

57

Co-operative interactions between NFAT (nuclear factor of activated T cells) c1 and the zinc finger transcription factors Sp1/Sp3 and Egr-1 regulate MT1-MMP (membrane type 1 matrix metalloproteinase) transcription by glomerular mesangial cells.  

PubMed

The transition of normally quiescent glomerular MCs (mesangial cells) to a highly proliferative phenotype with characteristics of myofibroblasts is a process commonly observed in inflammatory diseases affecting the renal glomerulus, the ultimate result of which is glomerulosclerosis. Generation of proteolytically active MMP (matrix metalloproteinase)-2 by the membrane-associated membrane type 1 (MT1)-MMP is responsible for the transition of mesangial cells to the myofibroblast phenotype [Turck, Pollock, Lee, Marti and Lovett (1996) J. Biol. Chem. 271, 15074-15083]. In the present study, we show that the expression of MT1-MMP within the context of MCs is mediated by three discrete cis -acting elements: a proximal non-canonical Sp1 site that preferentially binds Sp1; an overlapping Sp1/Egr-1-binding site that preferentially binds Egr-1; and a more distal binding site for the NFAT (nuclear factor of activated T cells) that binds the NFAT c1 isoform present in MC nuclear extracts. Transfection with an NFAT c1 expression plasmid, or activation of calcineurin with a calcium ionophore, yielded major increases in NFAT c1 nuclear DNA-binding activity, MT1-MMP transcription and protein synthesis, which were additive with the lower levels of transactivation provided by the proximal Sp1 and the overlapping Sp1/Egr-1 sites. Specific binding of NFAT c1 to the MT1-MMP promoter was confirmed by chromatin immunoprecipitation studies, while MT1-MMP expression was suppressed by treatment with the calcineurin inhibitor, cyclosporin A. These studies are the first demonstration that a specific NFAT isoform enhances transcription of an MMP (MT1-MMP) that plays a major role in the proteolytic events that are a dominant feature of acute glomerular inflammation. Suppression of MT1-MMP by commonly used calcineurin inhibitors may play a role in the development of renal fibrosis following renal transplantation. PMID:14979875

Alfonso-Jaume, Maria Alejandra; Mahimkar, Rajeev; Lovett, David H

2004-06-15

58

Human collagen Krox up-regulates type I collagen expression in normal and scleroderma fibroblasts through interaction with Sp1 and Sp3 transcription factors.  

PubMed

Despite several investigations, the transcriptional mechanisms that regulate the expression of both type I collagen genes (COL1A1 and COL1A2) in either physiological or pathological situations, such as scleroderma, are not completely known. We have investigated the role of hc-Krox transcription factor on type I collagen expression by human dermal fibroblasts. hc-Krox exerted a stimulating effect on type I collagen protein synthesis and enhanced the corresponding mRNA steady-state levels of COL1A1 and COL1A2 in foreskin fibroblasts (FF), adult normal fibroblasts (ANF), and scleroderma fibroblasts (SF). Forced hc-Krox expression was found to up-regulate COL1A1 transcription through a -112/-61-bp sequence in FF, ANF, and SF. Knockdown of hc-Krox by short interfering RNA and decoy strategies confirmed the transactivating effect of hc-Krox and decreased substantially COL1A1 transcription levels in all fibro-blast types. The -112/-61-bp sequence bound specifically hc-Krox but also Sp1 and CBF. Attempts to elucidate the potential interactions between hc-Krox, Sp1, and Sp3 revealed that all of them co-immunoprecipitate from FF cellular extracts when a c-Krox antibody was used and bind to the COL1A1 promoter in chromatin immunoprecipitation assays. Moreover, hc-Krox DNA binding activity to its COL1A1-responsive element is increased in SF, cells producing higher amounts of type I collagen compared with ANF and FF. These data suggest that the regulation of COL1A1 gene transcription in human dermal fibroblasts involves a complex machinery that implicates at least three transcription proteins, hc-Krox, Sp1, and Sp3, which could act in concert to up-regulate COL1A1 transcriptional activity and provide evidence for a pro-fibrotic role of hc-Krox. PMID:17698844

Kypriotou, Magdalini; Beauchef, Gallic; Chadjichristos, Christos; Widom, Russell; Renard, Emmanuelle; Jimenez, Sergio A; Korn, Joseph; Maquart, François-Xavier; Oddos, Thierry; Von Stetten, Otto; Pujol, Jean-Pierre; Galéra, Philippe

2007-08-13

59

CRABP2 Promotes Myoblast Differentiation and Is Modulated by the Transcription Factors MyoD and Sp1 in C2C12 Cells  

PubMed Central

Cellular retinoic acid binding protein 2 (CRABP2), a member of a family of specific carrier proteins for Vitamin A, belongs to a family of small cytosolic lipid binding proteins. Our previous study suggested that CRABP2 was involved in skeletal muscle development; however, the molecular function and regulatory mechanism of CRABP2 in myogenesis remained unclear. In this study, we found that the expression of the CRABP2 gene was upregulated during C2C12 differentiation. An over-expression assay revealed that CRABP2 promotes myogenic transformation by regulating the cell cycle during C2C12 differentiation. The region from ?459 to ?4 bp was identified as the core promoter and contains a TATA box, a GC box and binding sites for the transcription factors MyoD and Sp1. Over-expression, site-directed mutagenesis and EMSA assays indicated that the transcription factors MyoD and Sp1 regulate CRABP2 expression and promote myoblast differentiation in C2C12 cells.

Yuan, Jing; Tang, Zhonglin; Yang, Shulin; Li, Kui

2013-01-01

60

NS1 protein of parvovirus B19 interacts directly with DNA sequences of the p6 promoter and with the cellular transcription factors Sp1/Sp3.  

PubMed

The nonstructural proteins of parvovirus exert a variety of disparate functions during viral infection ranging from promoter regulation, involvement in DNA replication, and induction of apoptosis. Our interest was focused on the possible mechanism by which the NS1 protein mediates its effects on the p6 promoter of parvovirus B19. It is known that the p6 promoter is highly active in different cell lines and interaction with the viral NS1 protein results in a further increase of the activity. The protein may function by binding directly to the viral DNA or via an indirect binding through interaction with cellular transcription factors bound to the promoter. We examined the interaction of the NS1 protein with cellular transcription factors which are involved in regulating the promoter activity. After purified baculovirus-expressed NS1 protein in gel retardation assays was added, an altered complex formation was observed, indicating that NS1 protein interacts with Sp1/Sp3 transcription factors. Enzyme-linked immunosorbent assays verified these findings. The direct interaction of NS1 protein with p6 promoter elements was analyzed by a coprecipitation assay whereby labeled oligonucleotides spanning the entire promoter region were incubated with NS1 protein followed by an immunoprecipitation with NS1-specific antibodies. An eight-nucleotide-long, almost palindromic sequence (AGGGCGGA) was found as potential NS1-binding motif. Footprint analysis with oligonucleotides containing this DNA motif confirmed this result. Thus, transcriptional regulation by the NS1 protein may involve both the interaction with Sp1/Sp3 that binds to the promoter region and direct binding of NS1 to the promoter DNA. PMID:11853402

Raab, Ulla; Beckenlehner, Karin; Lowin, Torsten; Niller, Hans-Helmut; Doyle, Sean; Modrow, Susanne

2002-02-01

61

O glycosylation of an Sp1-derived peptide blocks known Sp1 protein interactions.  

PubMed Central

The O-linked N-acetylglucosamine (O-GlcNAc) modification of proteins is dynamic and abundant in the nucleus and cytosol. Several transcription factors, including Sp1, have been shown to contain this modification; however, the functional role of O-GlcNAc in these proteins has not been determined. In this paper we describe the use of the previously characterized glutamine-rich transactivation domain of Sp1 (B-c) as a model to investigate the role of O-GlcNAc in Sp1's transcriptionally relevant protein-to-protein interactions with the TATA-binding-protein-associated factor (TAF110) and holo-Sp1. When the model Sp1 peptide was overexpressed in primate cells, this 97-amino-acid domain of Sp1 was found to contain a dominant O-GlcNAc residue at high stoichiometry, which allowed the mapping and mutagenesis of this glycosylation site. In vitro interaction studies between this segment of Sp1 and Drosophila TAF110 or holo-Sp1 indicate that the O-GlcNAc modification functions to inhibit the largely hydrophobic interactions between these proteins. In HeLa cells, the mutation at the mapped glycosylation site was permissive for transcriptional activation. We propose the hypothesis that the removal of O-GlcNAc from an interaction domain can be a signal for protein association. O-GlcNAc may thereby prevent untimely and ectopic interactions.

Roos, M D; Su, K; Baker, J R; Kudlow, J E

1997-01-01

62

Factors That Predict Digital Game Play  

Microsoft Academic Search

This study examines gender, race, and the need for social gratification as significant predictors of the number of hours of weekday and weekend digital game play. Secondary analysis of data from the National Center for Education Statistics' Education Longitudinal Study of 2002 revealed that that Caucasian and Asian students were associated with diminished digital game play, whereas African Americans students

Mary E. Green; Mary Nell McNeese

2008-01-01

63

Sp1 and Sp3 transcription factors mediate trichostatin a-induced and basal expression of extracellular superoxide dismutase  

Microsoft Academic Search

Extracellular superoxide dismutase (EC-SOD) is the major extracellular antioxidant enzyme and may play a critical role in the pathogenesis of a variety of pulmonary, neurological, and cardiovascular diseases. We report here that exposure to the deacetylase inhibitor trichostatin A (TSA) induces EC-SOD mRNA levels in mIMCD3 and Hepa 1-6 cells, but reduces EC-SOD mRNA levels in MLg cells. To determine

Igor N. Zelko; Rodney J. Folz

2004-01-01

64

Fibroblast growth factor-2 up-regulates the expression of nestin through the Ras-Raf-ERK-Sp1 signaling axis in C6 glioma cells.  

PubMed

Nestin is a 240-kDa intermediate filament protein expressed mainly in neural and myogenic stem cells. Although a substantial number of studies have focused on the expression of nestin during development of the central nervous system, little is known about the factors that induce and regulate its expression. Fibroblast growth factor-2 (FGF-2) is an effective mitogen and stimulates the proliferation and differentiation of a subset of nestin-expressing cells, including neural progenitor cells, glial precursor cells, and smooth muscle cells. To assess whether FGF-2 is a potent factor that induces the expression of nestin, C6 glioma cells were used. The results showed that nestin expression was up-regulated by FGF-2 via de novo RNA and protein synthesis. Our RT-PCR results showed that C6 glioma cells express FGFR1/3, and FGFRs is required for FGF-2-induced nestin expression. Further signaling analysis also revealed that FGF-2-induced nestin expression is mediated through FGFR-MAPK-ERK signaling axis and the transcriptional factor Sp1. These findings provide new insight into the regulation of nestin in glial system and enable the further studies on the function of nestin in glial cells. PMID:23611784

Chang, Kai-Wei; Huang, Yuan-Li; Wong, Zong-Ruei; Su, Peng-Han; Huang, Bu-Miin; Ju, Tsai-Kai; Yang, Hsi-Yuan

2013-04-20

65

Unique aspects of transcriptional regulation in neurons – nuances in NF?B and Sp1-related factors  

Microsoft Academic Search

The unique physiology and function of neurons create differences in their cellular physiology, including their regulation of gene expression. We began several years ago exploring the relationships between the NF?B transcription factor, neuronal survival, and glutamate receptor activation in telencephalic neurons. These studies led us to conclude that this population of cells is nearly incapable of activating the NF?B that

Xianrong R. Mao; Andrea M. Moerman-Herzog; Yuzhi Chen; Steven W. Barger

2009-01-01

66

Zebrafish Sp1-like protein is structurally and functionally comparable to human Sp1.  

PubMed

The transcription factor Sp1 is a regulator of TATA-less genes. It belongs to the Cys?-His? zinc finger domain-containing family. A zebrafish cDNA encoding a peptide homologous to mammalian Sp1 was cloned and inserted into a pET43.1a vector and expressed in Escherichia coli Rosetta (DE3) cells as a Nus-His-tag fusion protein. After induction with isopropyl thiogalactoside, the protein was purified with a Ni-Sepharose column, and approximately 5-8 mg of pure protein was obtained per liter of culture. The primary sequence and the predicted partial tertiary structure of the potential recombinant zebrafish Sp1 protein are similar to those of human Sp1. The DNA affinity precipitation assay and dual-luciferase promoter activity assay further confirm the nature of the recombinant zebrafish Sp1 protein as a transcription factor. Our results show that zebrafish Sp1-like protein is structurally and functionally comparable to human Sp1. PMID:21040790

Lin, Cha-Jang; Hsiao, Tsun-Hsien; Chung, Yi-Shao; Chang, Wen-Ni; Yeh, Trai-Ming; Chen, Bing-Hung; Fu, Tzu-Fun

2010-10-30

67

The myeloid-cell-specific c-fes promoter is regulated by Sp1, PU.1, and a novel transcription factor.  

PubMed

The protein product of the c-fps/fes (c-fes) proto-oncogene has been implicated in the normal development of myeloid cells (macrophages and neutrophils). mRNA for c-fes has been detected exclusively in myeloid cells and vascular endothelial cells in adult mammals. Although a 13-kilobase-pair (kb) human c-fes transgene exhibits high levels of expression in mice, the sequences that confer myeloid-cell-specific expression of the human c-fes gene have not been defined. Transient-transfection experiments demonstrated that plasmids containing 446 bp of c-fes 5'-flanking sequences linked to a luciferase reporter gene were active exclusively in myeloid cells. No other DNA element within the 13-kb human c-fes locus contained positive cis-acting elements, with the exception of a weakly active region within the 3'-flanking sequences. DNase I footprinting assays revealed four distinct sites that bind myeloid nuclear proteins (-408 to -386, -293 to -254, -76 to -65, and -34 to +3). However, the first two footprints resided in sequences that were largely dispensable for transient activity. Plasmids containing 151 bp of 5'-flanking sequences confer myeloid-cell-specific gene expression. Electrophoretic mobility shift analyses demonstrated that the 151-bp region contains nuclear protein binding sites for Sp1, PU.1, and/or Elf-1, and a novel factor. This unidentified factor binds immediately 3' of the PU.1/Elf-1 sites and appears to be myeloid cell specific. Mutation of the PU.1/Elf-1 site or the 3' site (FP4-3') within the context of the c-fes promoter resulted in substantially reduced activity in transient transfections. Furthermore, transient-cotransfection assay demonstrated that PU.1 (and not Elf-1) can transactivate the c-fes promoter in nonmyeloid cell lines. We conclude that the human c-fes gene contains a strong myeloid-cell-specific promoter that is regulated by Sp1, PU.1, and a novel transcription factor. PMID:8657143

Heydemann, A; Juang, G; Hennessy, K; Parmacek, M S; Simon, M C

1996-04-01

68

Playing styles and possible causative factors in dogs' behaviour when playing with humans  

Microsoft Academic Search

Individual differences and causative factors could modify the behaviour of dogs in object related games played with a human partner. In a two-by-two within-subject design we observed 68 family dogs' behaviour when playing two different types of games (ball game and tugging) with two different play partners (owner or unfamiliar experimenter) in order to categorize each dog's playing style. In

Lilla Toth; M arta Gacsi; Adam Miklosi

69

Association Between COLIA1 Sp1 Alleles and Femoral Neck Geometry  

Microsoft Academic Search

Genetic factors play an important role in the pathogenesis of osteoporosis by affecting bone mineral density and other predictors of osteoporotic fracture risk such as ultrasound properties of bone and skeletal geometry. We previously identified a polymorphism of a Sp1 binding site in the Collagen Type 1 Alpha 1 gene (COLIA1) that has been associated with reduced BMD and an

A. M. Qureshi; F. E. A. McGuigan; D. G. Seymour; J. D. Hutchison; D. M. Reid; S. H. Ralston

2001-01-01

70

Co-operation of the transcription factor hepatocyte nuclear factor-4 with Sp1 or Sp3 leads to transcriptional activation of the human haem oxygenase-1 gene promoter in a hepatoma cell line.  

PubMed

We reported previously that the 5'-flanking region (nucleotides -1976 to -1655) of the human haem oxygenase-1 ( hHO-1 ) gene enhances hHO-1 promoter activity in human hepatoma HepG2 cells, but not in HeLa cells [Takahashi, Takahashi, Ito, Nagano, Shibahara and Miura (1999) Biochim. Biophys. Acta 1447, 231-235]. To define more precisely the regulatory elements involved, in the present study we have functionally dissected this region and localized the enhancer to a 50 bp fragment (-1793 to -1744). Site-direct mutagenesis analysis revealed that two regions were responsible for this enhancer activity, i.e. a hepatocyte nuclear factor-4 (HNF-4) homologous region and a GC box motif homologous region. Mutation in either region alone moderately decreased enhancer activity. However, mutations in both regions reduced promoter activity to the basal level. Electrophoretic mobility-shift assays demonstrated that the P5-2 fragment (-1793 to -1744) interacted with at least two nuclear factors, i.e. HNF-4 and Sp1/Sp3. Co-transfection experiments using Drosophila SL2 cells revealed that HNF-4 and Sp1/Sp3 synergistically stimulated the enhancer activity of the P5-2 fragment. These results indicate that co-operation of HNF-4 with Sp1 or Sp3 leads to the activation of hHO-1 gene expression in hepatoma cells. PMID:12133007

Takahashi, Shigeru; Matsuura, Naomi; Kurokawa, Takako; Takahashi, Yuji; Miura, Takashi

2002-11-01

71

p21WAF1/CIP1 Is Upregulated by the Geranylgeranyltransferase I Inhibitor GGTI-298 through a Transforming Growth Factor ?- and Sp1-Responsive Element: Involvement of the Small GTPase RhoA  

PubMed Central

We have recently reported that the geranylgeranyltransferase I inhibitor GGTI-298 arrests human tumor cells at the G1 phase of the cell cycle and increases the protein and RNA levels of the cyclin-dependent kinase inhibitor p21WAF1/CIP1. Here, we show that GGTI-298 acts at the transcriptional level to induce p21WAF1/CIP1 in a human pancreatic carcinoma cell line, Panc-1. This upregulation of p21WAF1/CIP1 promoter was selective, since GGTI-298 inhibited serum responsive element- and E2F-mediated transcription. A functional analysis of the p21WAF1/CIP1 promoter showed that a GC-rich region located between positions ?83 and ?74, which contains a transforming growth factor ?-responsive element and one Sp1-binding site, is sufficient for the upregulation of p21WAF1/CIP1 promoter by GGTI-298. Electrophoretic mobility shift assays showed a small increase in the amount of DNA-bound Sp1-Sp3 complexes. Furthermore, the analysis of Sp1 transcriptional activity in GGTI-298-treated cells by using GAL4-Sp1 chimera or Sp1-chloramphenicol acetyltransferase reporter revealed a significant increase in Sp1-mediated transcription. Moreover, GGTI-298 treatment also resulted in increased Sp1 and Sp3 phosphorylation. These results suggest that GGTI-298-mediated upregulation of p21WAF1/CIP1 involves both an increase in the amount of DNA-bound Sp1-Sp3 and enhancement of Sp1 transcriptional activity. To identify the geranylgeranylated protein(s) involved in p21WAF1/CIP1 transcriptional activation, we analyzed the effects of the small GTPases Rac1 and RhoA on p21WAF1/CIP1 promoter activity. The dominant negative mutant of RhoA, but not Rac1, was able to activate p21WAF1/CIP1. In contrast, constitutively active RhoA repressed p21WAF1/CIP1. Accordingly, the ADP-ribosyl transferase C3, which specifically inhibits Rho proteins, enhanced the activity of p21WAF1/CIP1. Taken together, these results suggest that one mechanism by which GGTI-298 upregulates p21WAF1/CIP1 transcription is by preventing the small GTPase RhoA from repressing p21WAF1/CIP1 induction.

Adnane, Jalila; Bizouarn, Francisco A.; Qian, Yimin; Hamilton, Andrew D.; Sebti, Said M.

1998-01-01

72

Play.  

ERIC Educational Resources Information Center

Contends that, in childhood, work and play seem to come together. Says that for young children their play is their work, and the more adults encourage children to play, the more they emphasize important lifelong resource. Examines some uses of children's play, making and building, artwork, dramatic play, monsters and superheroes, gun play, and…

Rogers, Fred; Sharapan, Hedda

1993-01-01

73

Involvement of specific proteins (Sp1/Sp3) and nuclear factor Y in basal transcription of the distal promoter of the rat pyruvate carboxylase gene in {beta}-cells  

SciTech Connect

Pyruvate carboxylase plays diverse roles in different biosynthetic pathways, including glucose-induced insulin secretion in pancreatic {beta}-cells. We have localized the control region of the P2 promoter by generating a series of 5'-nested deletion constructs, and both 25- and 9-bp internal deletion constructs, as well as by performing site-directed mutagenesis. Transient transfections of these constructs into INS-1 cells identified a CCAAT box and a GC box that are located at -65/-61 and -48/-41, respectively, as the important determinants. Disruption of the GC box resulted in a 4-fold reduction of the reporter activity, while disruption of the proximal CCAAT box (-65/-61) but not the distal CCAAT box (-95/-91) increased the reporter activity by 3-fold. Simultaneous disruptions of both the GC box and the CCAAT box reduced the reporter activity to a level that was close to that of the single GC box mutation. Electrophoretic mobility shift assays (EMSAs) and supershift EMSAs using nuclear extract from INS-1 cells demonstrated that Sp1 and Sp3 bind a GC box while the nuclear factor Y was shown to bind the proximal but not the distal CCAAT box.

Sunyakumthorn, Piyanate [Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok 10400 (Thailand); Boonsaen, Thirajit [Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok 10400 (Thailand); Boonsaeng, Vichai [Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok 10400 (Thailand); Wallace, John C. [School of Molecular and Biomedical Science, University of Adelaide, Adelaide, SA 5005 (Australia); Jitrapakdee, Sarawut [Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok 10400 (Thailand)]. E-mail: scsji@mahidol.ac.th

2005-04-01

74

Arsenic trioxide-induced hERG K(+) channel deficiency can be rescued by matrine and oxymatrine through up-regulating transcription factor Sp1 expression.  

PubMed

The human ether-a-go-go-related gene (hERG) encodes the rapidly activating, delayed rectifier potassium channel (IKr) important for cardiac repolarization. Dysfunction of the hERG channel can cause Long QT Syndrome (LQTS). A wide variety of structurally diverse therapeutic compounds reduce the hERG current by acute direct inhibition of the hERG current or/and selective disruption of hERG protein expression. Arsenic trioxide (As(2)O(3)), which is used to treat acute promyelocytic leukemia, can cause LQTS type 2 (LQT2) by reducing the hERG current through the diversion of hERG trafficking to the cytoplasmic membrane. This cardiotoxicity limits its clinical applications. Our aim was to develop cardioprotective agents to decrease As(2)O(3)-induced cardiotoxicity. We reported that superfusion of hERG-expressing HEK293 (hERG-HEK) cells with matrine (1, 10 ?M) increased the hERG current by promoting hERG channel activation. Long-term treatment with 1 ?M matrine or oxymatrine increased expression of the hERG protein and rescued the hERG surface expression disrupted by As(2)O(3). In addition, Matrine and oxymatrine significantly shortened action potential duration prolonged by As(2)O(3) in guinea pig ventricular myocytes. These results were ascribed to the up-regulation of hERG at both mRNA and protein levels via an increase in the expression of transcription factor Sp1, an established transactivator of the hERG gene. Therefore, matrine and oxymatrine may have the potential to cure LQT2 as a potassium channel activator by promoting hERG channel activation and increasing hERG channel expression. PMID:23103450

Zhang, Ying; Dong, Zengxiang; Jin, Liyan; Zhang, Kaiping; Zhao, Xin; Fu, Jia; Gong, Yan; Sun, Mingming; Yang, Baofeng; Li, Baoxin

2012-10-24

75

Demographic factors and playing variables in online computer gaming.  

PubMed

Despite the growing popularity of online game playing, there has been no primary survey of its players. Therefore, an online questionnaire survey was used to examine basic demographic factors of online computer game players who played the popular online game Everquest (i.e., gender, age, marital status, nationality, education level, occupation). The survey also examined playing frequency (i.e., amount of time spent playing the game a week), playing history (i.e., how long they had been playing the game, who they played the game with, whether they had ever gender swapped their game character), the favorite and least favorite aspects of playing the game, and what they sacrifice (if anything) to play the game. Results showed that 81% of online game players were male, and that the mean age of players was 27.9 years of age. For many players, the social aspects of the game were the most important factor in playing. A small minority of players appear to play excessively (over 80 h a week), and results suggest that a small minority sacrifice important activities in order to play (e.g., sleep, time with family and/or partner, work, or schooling). PMID:15331036

Griffiths, Mark D; Davies, Mark N O; Chappell, Darren

2004-08-01

76

Helicobacter pylori stimulates host vascular endothelial growth factor-A (vegf-A) gene expression via MEK\\/ERK-dependent activation of Sp1 and Sp3  

Microsoft Academic Search

VEGF-A is a key regulator of inflammatory and tumor-associated angiogenesis. H. pylori plays a critical role in the pathogenesis of benign and malignant gastric diseases. It has been suggested that H. pylori infection is associated with activation of host angiogenesis, however, underlying mechanisms as well as angiogenic growth factors activated by the bacterium have not yet been identified. Therefore, we

Mathias Z. Strowski; Thorsten Cramer; Georgia Schäfer; Stefan Jüttner; Anna Walduck; Ernestina Schipani; Wolfgang Kemmner; Silja Wessler; Christian Wunder; Matthias Weber; Thomas F. Meyer; Bertram Wiedenmann; Thomas Jöns; Michael Naumann; Michael Höcker

2003-01-01

77

Isolation and characterization of the 5´-upstream region of the human voltage-gated Ca(2+) channel ? 2?-1 auxiliary subunit gene: promoter analysis and regulation by transcription factor Sp1.  

PubMed

The ?2? proteins are auxiliary subunits of high-voltage-activated Ca(2+) channels associated with alterations of surface expression, kinetics, and voltage-dependent properties of the channel complex. Four mammalian genes and several splice ?2? subunit variants have been cloned and described, though very little information concerning the transcriptional mechanisms that regulate their expression is available. Here, we report the identification and characterization of the human ?2?-1 subunit gene promoter and its regulation by specific transcription factor 1 (Sp1). Transient transfection of human neuroblastoma SH-SY5Y cells with a promoter/luciferase reporter construct revealed a ~1.5 kb 5´-UTR fragment of the CACNA2D1 gene that produced high levels of luciferase activity. Deletional analysis of this sequence showed that the minimal promoter was located within a 413-bp region (nt -326 to +98) with respect to the transcription start site. In this region, no canonical TATA box was present, but a high GC content and five potential Sp1 binding sites were found. The ability of two of these sites to interact with the transcription factor was confirmed by electrophoretic mobility shift assays. Likewise, Sp1 overexpression enhanced promoter activity while siRNA-mediated Sp1 silencing significantly decreased the level of ?2? protein expressed in the SH-SY5Y cells, as well as reduced the amplitude of whole-cell patch clamp Ca(2+) currents in dorsal root ganglion neurons. This study thus represents the first identification of the transcriptional control region in the gene encoding the Ca(2+) channel ?2?-1 auxiliary subunit. PMID:23242029

Martínez-Hernández, Elizabeth; González-Ramírez, Ricardo; Sandoval, Alejandro; Cisneros, Bulmaro; Delgado-Lezama, Rodolfo; Felix, Ricardo

2012-12-15

78

The Sp(1)-Kepler problems  

NASA Astrophysics Data System (ADS)

Let n>=2 be a positive integer. To each irreducible representation ? of Sp(1), an Sp(1)-Kepler problem in dimension (4n-3) is constructed and analyzed. This system is superintegrable, and when n=2 it is equivalent to a generalized MICZ-Kepler problem in dimension of 5. The dynamical symmetry group of this system is O~*(4n) with the Hilbert space of bound states (?) being the unitary highest weight representation of O*~(4n) with highest weight, (-1,...,-1,-(1+?)), which occurs at the rightmost nontrivial reduction point in the Enright-Howe-Wallach classification diagram for the unitary highest weight modules. Here ? is the highest weight of ?. Furthermore, it is shown that the correspondence ?<-->(?) is the theta-correspondence for dual pair (Sp(1),O*(4n))?Sp(8n,R).

Meng, Guowu

2009-07-01

79

Low SP1 Expression Differentially Affects Intestinal-Type Compared with Diffuse-Type Gastric Adenocarcinoma  

PubMed Central

Specificity protein 1 (SP1) is an essential transcription factor that regulates multiple cancer-related genes. Because aberrant expression of SP1 is related to cancer development and progression, we focused on SP1 expression in gastric carcinoma and its correlation with disease outcomes. Although patient survival decreased as SP1 expression increased (P<0.05) in diffuse-type gastric cancer, the lack of SP1 expression in intestinal-type gastric cancer was significantly correlated with poor survival (P<0.05). The knockdown of SP1 in a high SP1-expressing intestinal-type gastric cell line, MKN28, increased migration and invasion but decreased proliferation. Microarray data in SP1 siRNA-transfected MKN28 revealed that the genes inhibiting migration were downregulated, whereas the genes negatively facilitating proliferation were increased. However, both migration and invasion were decreased by forced SP1 expression in a low SP1-expressing intestinal-type gastric cell line, AGS. Unlike the intestinal-type, in a high SP1-expressing diffuse-type gastric cell line, SNU484, migration and invasion were decreased by SP1 siRNA. In contrast to previous studies that did not identify differences between the 2 histological types, our results reveal that low expression of SP1 is involved in cancer progression and metastasis and differentially affects intestinal-type compared with diffuse-type gastric adenocarcinoma.

Oh, Ensel; Erkin, Ozgur Cem; Jung, Hun Soon; Cho, Mi-Hyun; Kwon, Mi Jeong; Chae, Seoung Wan; Kim, Seok-Hyung; Wang, Li-Hui; Park, Min-Jeong; Lee, Su-Yeon; Yang, Ho Bin; Jia, Lina; Choi, Yoon-La; Shin, Young Kee

2013-01-01

80

The Sp(1)-Kepler problems  

SciTech Connect

Let n{>=}2 be a positive integer. To each irreducible representation {sigma} of Sp(1), an Sp(1)-Kepler problem in dimension (4n-3) is constructed and analyzed. This system is superintegrable, and when n=2 it is equivalent to a generalized MICZ-Kepler problem in dimension of 5. The dynamical symmetry group of this system is O-tilde*(4n) with the Hilbert space of bound states H({sigma}) being the unitary highest weight representation of O*-tilde(4n) with highest weight, (-1,{center_dot}{center_dot}{center_dot},-1,-(1+{sigma})), which occurs at the rightmost nontrivial reduction point in the Enright-Howe-Wallach classification diagram for the unitary highest weight modules. Here {sigma} is the highest weight of {sigma}. Furthermore, it is shown that the correspondence {sigma}{r_reversible}H({sigma}) is the theta-correspondence for dual pair (Sp(1),O*(4n))subset Sp(8n,R)

Meng Guowu [Department of Mathematics, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon (Hong Kong)

2009-07-15

81

Bifunctional properties of peroxisome proliferator-activated receptor gamma1 in KDR gene regulation mediated via interaction with both Sp1 and Sp3.  

PubMed

Vascular endothelial growth factor receptor 2 (KDR) plays a critical role in mediating a variety of vasculogenic and angiogenic processes, including diabetic retinopathy. We previously demonstrated that the promoter activity of the KDR gene in retinal capillary endothelial cells (RCECs) was regulated in part by the relative concentration of positive/negative transcription factors Sp1/Sp3. We also reported that the peroxisome proliferator-activated receptor (PPAR)gamma ligand could inhibit intraocular angiogenesis. In the present study, the role of PPARgamma1 in KDR gene regulation in RCECs was examined. PPARgamma1 protein physically interacted with both Sp1 and Sp3. Transactivation and electrophoretic mobility shift assays clearly demonstrated novel findings that PPARgamma1 increased KDR promoter activity by enhancing the interaction between Sp1, but not Sp3, and KDR promoter region without its ligand in RCECs. The ligand-binding site but not the DNA binding site of PPARgamma1 enhanced the interaction between Sp1 and KDR promoter region. Conversely, PPARgamma1 ligand 15-deoxy Delta (12,14)-prostaglandin J2 dose-dependently suppressed the binding of KDR promoter region with both Sp1 and Sp3, resulting an inhibition of KDR gene expression. In conclusion, PPARgamma1 has bifunctional properties in the regulation of KDR gene expression mediated via interaction with both Sp1 and Sp3. PMID:15111490

Sassa, Yukio; Hata, Yasuaki; Aiello, Lloyd Paul; Taniguchi, Yukio; Kohno, Kimitoshi; Ishibashi, Tatsuro

2004-05-01

82

Identification of novel Sp1 targets involved in proliferation and cancer by functional genomics.  

PubMed

Sp1 is a transcription factor regulating many genes through its DNA binding domain, containing three zinc fingers. We were interested in identifying target genes regulated by Sp1, particularly those involved in proliferation and cancer. Our approach was to treat HeLa cells with a siRNA directed against Sp1 mRNA to decrease the expression of Sp1 and, in turn, the genes activated by this transcription factor. Sp1-siRNA treatment led to a great number of differentially expressed genes as determined by whole genome cDNA microarray analysis. Underexpressed genes were selected since they represent putative genes activated by Sp1 and classified in six Gene Onthology categories, namely proliferation and cancer, mRNA processing, lipid metabolism, glucidic metabolism, transcription and translation. Putative Sp1 binding sites were found in the promoters of the selected genes using the Match™ software. After literature mining, 11 genes were selected for further validation. Underexpression by qRT-PCR was confirmed for the 11 genes plus Sp1 in HeLa cells after Sp1-siRNA treatment. EMSA and ChIP assays were performed to test for binding of Sp1 to the promoters of these genes. We observed binding of Sp1 to the promoters of RAB20, FGF21, IHPK2, ARHGAP18, NPM3, SRSF7, CALM3, PGD and Sp1 itself. Furthermore, the mRNA levels of RAB20, FGF21 and IHPK2 and luciferase activity for these three genes related to proliferation and cancer, were determined after overexpression of Sp1 in HeLa cells, to confirm their regulation by Sp1. Involvement of these three genes in proliferation was validated by gene silencing using polypurine reverse hoogsteen hairpins. PMID:23018034

Oleaga, Carlota; Welten, Sabine; Belloc, Audrey; Solé, Anna; Rodriguez, Laura; Mencia, Núria; Selga, Elisabet; Tapias, Alicia; Noé, Veronique; Ciudad, Carlos J

2012-09-25

83

Regulation of poly(ADP-ribose) polymerase-1 (PARP-1) gene expression through the post-translational modification of Sp1: a nuclear target protein of PARP-1  

PubMed Central

Background Poly(ADP-ribose) polymerase-1 (PARP-1) is a nuclear enzyme that plays critical functions in many biological processes, including DNA repair and gene transcription. The main function of PARP-1 is to catalyze the transfer of ADP-ribose units from nicotinamide adenine dinucleotide (NAD+) to a large array of acceptor proteins, which comprises histones, transcription factors, as well as PARP-1 itself. We have previously demonstrated that transcription of the PARP-1 gene essentially rely on the opposite regulatory actions of two distinct transcription factors, Sp1 and NFI. In the present study, we examined whether suppression of PARP-1 expression in embryonic fibroblasts derived from PARP-1 knockout mice (PARP-1-/-) might alter the expression and/or DNA binding properties of Sp1 and NFI. We also explored the possibility that Sp1 or NFI (or both) may represent target proteins of PARP-1 activity. Results Expression of both Sp1 and NFI was found to be considerably reduced in PARP-1-/- cells. Co-immunoprecipitation assays revealed that PARP-1 physically interacts with Sp1 in a DNA-independent manner, but neither with Sp3 nor NFI, in PARP-1+/+ cells. In addition, in vitro PARP assays indicated that PARP-1 could catalyze the addition of polymer of ADP-ribose to Sp1, which also translated into a reduction of Sp1 binding to its consensus DNA target site. Transfection of the PARP-1 promoter into both PARP-1+/+ and PARP-1-/- cells revealed that the lack of PARP-1 expression in PARP-1-/- cells also results in a strong increase in PARP-1 promoter activity. This influence of PARP-1 was found to rely on the presence of the Sp1 sites present on the basal PARP-1 promoter as their mutation entirely abolished the increased promoter activity observed in PARP-1-/- cells. Subjecting PARP-1+/+ cells to an oxidative challenge with hydrogen peroxide to increase PARP-1 activity translated into a dramatic reduction in the DNA binding properties of Sp1. However, its suppression by the inhibitor PJ34 improved DNA binding of Sp1 and led to a dramatic increase in PARP-1 promoter function. Conclusion Our results therefore recognized Sp1 as a target protein of PARP-1 activity, the addition of polymer of ADP-ribose to this transcription factor restricting its positive regulatory influence on gene transcription.

Zaniolo, Karine; Desnoyers, Serge; Leclerc, Steeve; Guerin, Sylvain L

2007-01-01

84

Sp1 modifies leg-to-wing transdetermination in Drosophila.  

PubMed

During Drosophila development, the transcription factor Sp1 is necessary for proper leg growth and also to repress wing development. Here we test the role of Sp1 during imaginal disc regeneration. Ubiquitous expression of wg induces a regeneration blastema in the dorsal aspect of the leg disc. Within this outgrowth, the wing selector gene vg is activated in some cells, changing their fate to wing identity in a process known as transdetermination. In this report we demonstrate that reducing the gene copy number of Sp1 significantly increases both the frequency and the area of transdetermination in regenerating leg discs. By examining the expression of known Sp1 target genes, we also show that the proximo-distal patterning gene dachshund is downregulated dorsally, leading to a break in its normal ring-shaped expression pattern. We further report that transdetermination, as evidenced by Vg expression, is only observed when there is a broken ring of Dachshund expression. Combined, these studies establish a role for Sp1 in leg-to-wing transdetermination. PMID:23165292

Ing, Thomas; Tseng, Alexander; Sustar, Anne; Schubiger, Gerold

2012-11-17

85

Histone deacetylase inhibitors prevent oxidative neuronal death independent of expanded polyglutamine repeats via an Sp1-dependent pathway  

Microsoft Academic Search

Oxidative stress is believed to be an important mediator of neurodegeneration. However, the transcriptional pathways induced in neurons by oxidative stress that activate protective gene responses have yet to be fully delineated. We report that the transcription factor Sp1 is acetylated in response to oxidative stress in neurons. Histone deacetylase (HDAC) inhibitors augment Sp1 acetylation, Sp1 DNA binding, and Sp1-dependent

Hoon Ryu; Junghee Lee; Beatrix A. Olofsson; Aziza Mwidau; Alpaslan Dedeoglu; Maria Escudero; Erik Flemington; Jane Azizkhan-Clifford; Robert J. Ferrante; Rajiv R. Ratan

2003-01-01

86

Zinc-Induced Formation of a Coactivator Complex Containing the Zinc-Sensing Transcription Factor MTF1, p300\\/CBP, and Sp1  

Microsoft Academic Search

Received 4 March 2008\\/Returned for modification 1 April 2008\\/Accepted 24 April 2008 Herein, the mechanisms of transactivation of gene expression by mouse metal response element-binding transcription factor 1 (MTF-1) were investigated. Evidence obtained from coimmunoprecipitation assays revealed that exposure of the cells to zinc resulted in the rapid formation of a multiprotein complex containing MTF-1, the histone acetyltransferase p300\\/CBP, and

Yong Li; Tomoki Kimura; Ryan W. Huyck; John H. Laity; Glen K. Andrews

2008-01-01

87

Video Game Playing and Gambling in Adolescents: Common Risk Factors  

Microsoft Academic Search

Video games and gambling often contain very similar elements with both providing intermittent rewards and elements of randomness. Furthermore, at a psychological and behavioral level, slot machine gambling, video lottery terminal (VLT) gambling and video game playing share many of the same features. Despite the similarities between video game playing and gambling there have been very few studies that have

Richard T. A. Wood; Rina Gupta; Jeffrey L. Derevensky; Mark Griffiths

2004-01-01

88

Expression of alpha V integrin is modulated by Epstein-Barr virus nuclear antigen 3C and the metastasis suppressor Nm23-H1 through interaction with the GATA-1 and Sp1 transcription factors  

SciTech Connect

Epstein-Barr virus (EBV) is a lymphotrophic herpesvirus infecting most of the world's population. It is associated with a number of human lymphoid and epithelial tumors and lymphoproliferative diseases in immunocompromised patients. A subset of latent EBV antigens is required for immortalization of primary B-lymphocytes. The metastatic suppressor Nm23-H1 which is downregulated in human invasive breast carcinoma reduces the migration and metastatic activity of breast carcinoma cells when expressed from a heterologous promoter. Interestingly, the EBV nuclear antigen 3C (EBNA3C) reverses these activities of Nm23-H1. The alpha V integrins recognize a variety of ligands for signaling and are involved in cell migration and proliferation and also serve as major receptors for extracellular-matrix-mediated cell adhesion and migration. The goal of this study was to determine if Nm23-H1 and EBNA3C can modulate alpha V integrin expression and downstream activities. The results of our studies indicate that Nm23-H1 downregulates alpha V intregrin expression in a dose responsive manner. In contrast, EBNA3C can upregulate alpha V integrin expression. Furthermore, the study showed that the association of the Sp1 and GATA transcription factors with Nm23-H1 is required for modulation of the alpha V integrin activity. Thus, these results suggest a direct correlation between the alpha V integrin expression and the interaction of Nm23-H1 with EBNA3C.

Choudhuri, Tathagata [Department of Microbiology and The Tumor Virology Program of the Abramson Comprehensive Cancer Center, University of Pennsylvania School of Medicine, 201E Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA 19104 (United States); Verma, Subhash C. [Department of Microbiology and The Tumor Virology Program of the Abramson Comprehensive Cancer Center, University of Pennsylvania School of Medicine, 201E Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA 19104 (United States); Lan, Ke [Department of Microbiology and The Tumor Virology Program of the Abramson Comprehensive Cancer Center, University of Pennsylvania School of Medicine, 201E Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA 19104 (United States); Robertson, Erle S. [Department of Microbiology and The Tumor Virology Program of the Abramson Comprehensive Cancer Center, University of Pennsylvania School of Medicine, 201E Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA 19104 (United States)]. E-mail: erle@mail.med.upenn.edu

2006-07-20

89

Interplay of Posttranslational Modifications in Sp1 Mediates Sp1 Stability during Cell Cycle Progression  

Microsoft Academic Search

Although Sp1 is known to undergo posttranslational modifications such as phosphorylation, glycosylation, acetylation, sumoylation, and ubiquitination, little is known about the possible interplay between the different forms of Sp1 that may affect its overall levels. It is also unknown whether changes in the levels of Sp1 influence any biological cell processes. Here, we identified RNF4 as the ubiquitin E3 ligase

Yi-Ting Wang; Wen-Bin Yang; Wen-Chang Chang; Jan-Jong Hung

2011-01-01

90

Factors associated with symbolic play development in preschoolers with hearing impairments and language processing delays  

Microsoft Academic Search

A child's ability to play is dependent on various factors, both internal and environmental. This study examines the relationships between symbolic play development in children, language development in children, parental role behaviors and parenting stress. This project is specifically concerned with the development of play in relation to these other factors in a population of hearing impaired and language processing

Jennifer A Maltz

2003-01-01

91

Changes in gene expression induced by Sp1 knockdown differ from those caused by challenging Sp1 binding to gene promoters.  

PubMed

C/G-rich DNA regions, which include those recognized by the Sp1 transcription factor in several gene promoters, also encompass potential binding sites for the DNA-intercalating anthracyclines doxorubicin and WP631. We explored the differences between changes in gene expression caused by the ability of these drugs to compete with Sp1 for binding to DNA and those produced by Sp1 knockdown. By quantitative RT-PCR of around 100 genes, most of them involved in control of cell cycle progression, we found that the treatment of human MDA-MB231 breast carcinoma cells with bis-anthracycline WP631 for 24 h produced a profile of gene down-regulation markedly different from the profile caused by doxorubicin treatment or by stable Sp1 knockdown. These observations are rationalized by considering a near-specific effect of WP631 on Sp1 interaction with several gene promoters, thus representing potential therapeutic targets for WP631, in contrast to a less specific effect of reducing the availability of Sp1 through RNA interference. Genes down-regulated upon each treatment were mapped to their molecular and biological functions, which documented the down-regulation, among other things, of genes involved in mRNA transcription regulation, granting us insights into the effects of challenging the transactivation of gene expression by Sp1. PMID:21684359

Mansilla, Sylvia; Priebe, Waldemar; Portugal, José

2011-06-13

92

Analyzing coal mine productivity-factors that play  

SciTech Connect

This paper presents the methodology for analyzing the productivity of a coal mining operation. It stipulates that the only appropriate measure for incorporating the productivity of labor and machinery is economic: the output is the tonnage per shift and the impact is the cost per shift. Cost per shift is divided between capital cost, labor cost, and operating cost. These factors are manipulated, in this paper, until they yield an optimized approximation of actual productivity even in the absence of sufficient statistical data in a particular area.

Douglas, W.J.

1983-11-01

93

O-Linked N-Acetylglucosaminylation of Sp1 Inhibits the Human Immunodeficiency Virus Type 1 Promoter?  

PubMed Central

Human immunodeficiency virus type 1 (HIV-1) gene expression and replication are regulated by the promoter/enhancer located in the U3 region of the proviral 5? long terminal repeat (LTR). The binding of cellular transcription factors to specific regulatory sites in the 5? LTR is a key event in the replication cycle of HIV-1. Since transcriptional activity is regulated by the posttranslational modification of transcription factors with the monosaccharide O-linked N-acetyl-d-glucosamine (O-GlcNAc), we evaluated whether increased O-GlcNAcylation affects HIV-1 transcription. In the present study we demonstrate that treatment of HIV-1-infected lymphocytes with the O-GlcNAcylation-enhancing agent glucosamine (GlcN) repressed viral transcription in a dose-dependent manner. Overexpression of O-GlcNAc transferase (OGT), the sole known enzyme catalyzing the addition of O-GlcNAc to proteins, specifically inhibited the activity of the HIV-1 LTR promoter in different T-cell lines and in primary CD4+ T lymphocytes. Inhibition of HIV-1 LTR activity in infected T cells was most efficient (>95%) when OGT was recombinantly overexpressed prior to infection. O-GlcNAcylation of the transcription factor Sp1 and the presence of Sp1-binding sites in the LTR were found to be crucial for this inhibitory effect. From this study, we conclude that O-GlcNAcylation of Sp1 inhibits the activity of the HIV-1 LTR promoter. Modulation of Sp1 O-GlcNAcylation may play a role in the regulation of HIV-1 latency and activation and links viral replication to the glucose metabolism of the host cell. Hence, the establishment of a metabolic treatment might supplement the repertoire of antiretroviral therapies against AIDS.

Jochmann, Ramona; Thurau, Mathias; Jung, Susan; Hofmann, Christian; Naschberger, Elisabeth; Kremmer, Elisabeth; Harrer, Thomas; Miller, Matthew; Schaft, Niels; Sturzl, Michael

2009-01-01

94

Comparative integromics on FZD7 orthologs: conserved binding sites for PU.1, SP1, CCAAT-box and TCF/LEF/SOX transcription factors within 5'-promoter region of mammalian FZD7 orthologs.  

PubMed

Canonical WNT signals are transduced through Frizzled (FZD) family receptor and LRP5/LRP6 co-receptor to upregulate MYC, CCND1, FGF20, JAG1, WISP1 and DKK1 genes, while non-canonical WNT signals are transduced through FZD family receptor and PTK7/ROR2/RYK co-receptor to activate RHOA/RHOU/RAC/CDC42, JNK, PKC, NFAT and NLK signaling cascades. FZD7, expressed in the normal gastrointestinal tract, is upregulated in esophageal cancer, gastric cancer, colorectal cancer, and hepatocellular carcinoma. Here, chimpanzee FZD7 and cow Fzd7 genes were identified and characterized by using bioinformatics (Techint) and human intelligence (Humint). Chimpanzee FZD7 and cow Fzd7 genes were identified within NW_001232110.1 and AC173037.2 genome sequences, respectively. Chimpanzee FZD7 and cow Fzd7 showed 100% and 97.2% total-amino-acid identity with human FZD7. All of the nine amino-acid residues substituted between human FZD7 and human FzE3 were identical to those of human FZD7 in chimpanzee, cow, mouse and rat FZD7 orthologs. Functional analyses using FzE3 with multiple cloning artifacts and/or sequencing errors are invalid. FZD7 orthologs were seven-transmembrane proteins with extracellular Frizzled domain, leucine zipper motif around the 5th transmembrane domain, and cytoplasmic DVL- and PDZ-binding motifs. Ser550 and Ser556 of FZD7 orthologs were putative aPKC phosphorylation sites. Dimerization and Ser550/556 phosphorylation were predicted as regulatory mechanisms for the signaling through FZD7. Transcriptional start site of human FZD7 gene was 735-bp upstream of NM_003507.1 RefSeq 5'-end. In addition to gastrointestinal cancer, hepatocellular cancer and pancreatic cancer, human FZD7 mRNAs were expressed in blastocysts, undifferentiated embryonic stem (ES) cells, ES-derived endodermal progenitors, ES-derived neural progenitors, fetal cochlea, retinal pigment epithelium, olfactory epithelium, regenerating liver, and multiple sclerosis. Comparative genomics analyses revealed that the binding sites for PU.1, SP1/Krüppel-like, CCAAT-box, and TCF/LEF/SOX transcription factors were conserved among 5'-promoter regions of mammalian FZD7 orthologs. PMID:17273804

Katoh, Masuko; Katoh, Masaru

2007-03-01

95

Transcription factor specificity protein 1 (SP1) and activating protein 2alpha (AP-2alpha) regulate expression of human KCTD10 gene by binding to proximal region of promoter.  

PubMed

Potassium channel tetramerization domain-containing 10 gene (KCTD10) belongs to the polymerase delta-interacting protein 1 (PDIP1) gene family. Mouse KCTD10 was thought to interact with proliferating cell nuclear antigen and the small subunit of polymerase delta, and to have roles in DNA repair, DNA replication and cell-cycle control. To better understand the regulatory mechanism of KCTD10 expression, we characterized the promoter of human KCTD10 containing a 639 bp fragment of the 5'-flanking region (-609/+30). A primer extension assay identified the transcription start site as an A, 63 bp upstream of the start codon. The promoter region contains neither a TATA box nor a CCAAT box, but a CpG island was found near to the transcription start site. Deletion mutagenesis showed that the region from -108 to +30 was indispensable to the promoter activity, and site-directed mutation analysis in this proximal promoter region of KCTD10 revealed two important transcription regulatory elements of specificity protein 1 (SP1) and activating protein-2 (AP-2). An in vivo chromatin immunoprecipitation assay further demonstrated that SP1 and AP-2alpha could bind to this proximal promoter region. Moreover, using a luciferase reporter assay, quantitative real-time RT-PCR and western blot analysis, both overexpression and RNA interference of SP1 and AP-2alpha indicated that the binding of SP1 to the proximal promoter region stimulated the promoter activity and endogenous KCTD10 expression, whereas binding of AP-2alpha to this region showed opposite effects. PMID:19154347

Liu, Rushi; Zhou, Aidong; Ren, Daolong; He, Ailan; Hu, Xiang; Zhang, Wenfeng; Yang, Liping; Liu, Mingjun; Li, Hong; Zhou, Jianlin; Xiang, Shuanglin; Zhang, Jian

2009-01-16

96

Functional Analyses of Natural Variation in Sp1 Binding Sites of a TATA-Less Promoter  

Microsoft Academic Search

.   Within the lactate dehydrogenase-B (LdhB) proximal promoter is a region with multiple in vivo footprinted sites that resembles the binding site for the transcription\\u000a factor SP1. Like many sequences that regulate transcription rate, these Sp1 binding sites are well conserved among species\\u000a of the teleost fish Fundulus. The only exception is in the northern population of F. heteroclitus, where

Jeff A. Segal; J. Lynn Barnett; Douglas L. Crawford

1999-01-01

97

IRF1 suppresses Ki-67 promoter activity through interfering with Sp1 activation.  

PubMed

Interferon regulatory factor 1 (IRF1) shows tumor-suppressor activity by suppressing proliferation of cancer cells. To exert its anti-proliferative effects, this factor must ultimately control transcription of several key genes that regulate cell cycle progression. Here, we showed that Ki-67 gene is a novel proliferation-related downstream target of IRF1. IRF1 repressed Ki-67 gene transcription in a dose-dependent manner in human Ketr-3 and 786-O renal carcinoma cells. We previously cloned the Ki-67 core promoter which contained two functional Sp1 binding sites. Mutation of the two Sp1 binding sites abrogated Sp1-dependent enhancement of Ki-67 promoter activity. Forced elevation of IRF1 decreased endogenous Sp1 protein level. However, there was no effect on Sp1 mRNA level after transfected with IRF1. Our findings establish a casual series of events that connect anti-proliferative effects of IRF1 with the Ki-67 gene, which encodes a key regulator of the G1/S phase transition. It suggests that the inhibitory effect on Ki-67 gene expression mediated by decreasing level of Sp1 protein might be a novel function of the anti-tumor activity of IRF1. PMID:22890831

Chen, Feifei; Song, Jian; Di, Jiehui; Zhang, Qing; Tian, Hui; Zheng, Junnian

2012-08-14

98

Astaxanthin Suppresses MPP+-Induced Oxidative Damage in PC12 Cells through a Sp1/NR1 Signaling Pathway  

PubMed Central

Objective: To investigate astaxanthin (ATX) neuroprotection, and its mechanism, on a 1-methyl-4-phenyl-pyridine ion (MPP+)-induced cell model of Parkinson’s disease. Methods: Mature, differentiated PC12 cells treated with MPP+ were used as an in vitro cell model. The MTT assay was used to investigate cell viability after ATX treatment, and western blot analysis was used to observe Sp1 (activated transcription factor 1) and NR1 (NMDA receptor subunit 1) protein expression, real-time PCR was used to monitor Sp1 and NR1 mRNA, and cell immunofluorescence was used to determine the location of Sp1 and NR1 protein and the nuclear translocation of Sp1. Results: PC12 cell viability was significantly reduced by MPP+ treatment. The expression of Sp1 and NR1 mRNA and protein were increased compared with the control (p < 0.01). Following co-treatment with ATX and MPP+, cell viability was significantly increased, and Sp1 and NR1 mRNA and protein were decreased, compared with the MPP+ groups (p < 0.01). In addition, mithracycin A protected PC12 cells from oxidative stress caused by MPP+ by specifically inhibiting the expression of Sp1. Moreover, cell immunofluorescence revealed that ATX could suppress Sp1 nuclear transfer. Conclusion: ATX inhibited oxidative stress induced by MPP+ in PC12 cells, via the SP1/NR1 signaling pathway.

Ye, Qinyong; Zhang, Xiaodong; Huang, Bixia; Zhu, Yuangui; Chen, Xiaochun

2013-01-01

99

Retinoid-induced apoptosis and Sp1 cleavage occur independently of transcription and require caspase activation.  

PubMed Central

Vitamin A and its derivatives, the retinoids, are essential regulators of many important biological functions, including cell growth and differentiation, development, homeostasis, and carcinogenesis. Natural retinoids such as all-trans retinoic acid can induce cell differentiation and inhibit growth of certain cancer cells. We recently identified a novel class of synthetic retinoids with strong anti-cancer cell activities in vitro and in vivo which can induce apoptosis in several cancer cell lines. Using an electrophoretic mobility shift assay, we analyzed the DNA binding activity of several transcription factors in T cells treated with apoptotic retinoids. We found that the DNA binding activity of the general transcription factor Sp1 is lost in retinoid-treated T cells undergoing apoptosis. A truncated Sp1 protein is detected by immunoblot analysis, and cytosolic protein extracts prepared from apoptotic cells contain a protease activity which specifically cleaves purified Sp1 in vitro. This proteolysis of Sp1 can be inhibited by N-ethylmaleimide and iodoacetamide, indicating that a cysteine protease mediates cleavage of Sp1. Furthermore, inhibition of Sp1 cleavage by ZVAD-fmk and ZDEVD-fmk suggests that caspases are directly involved in this event. In fact, caspases 2 and 3 are activated in T cells after treatment with apoptotic retinoids. The peptide inhibitors also blocked retinoid-induced apoptosis, as well as processing of caspases and proteolysis of Sp1 and poly(ADP-ribose) polymerase in intact cells. Degradation of Sp1 occurs early during apoptosis and is therefore likely to have profound effects on the basal transcription status of the cell. Interestingly, retinoid-induced apoptosis does not require de novo mRNA and protein synthesis, suggesting that a novel mechanism of retinoid signaling is involved, triggering cell death in a transcriptional activation-independent, caspase-dependent manner.

Piedrafita, F J; Pfahl, M

1997-01-01

100

The adeno-associated virus type 2 p40 promoter requires a proximal Sp1 interaction and a p19 CArG-like element to facilitate Rep transactivation.  

PubMed Central

We have identified the sequence elements that are required for adeno-associated virus type 2 p40 promoter activity. Mutation of specific promoter elements showed that two Sp1 sites at approximately -50 (Sp1-50) and -70 (GGT-70) bp upstream of the start of the p40 messages were necessary for maximal promoter activity. As expected, the TATA site at -30 was also essential. In vitro DNA binding experiments confirmed that the Sp1-50 and GGT-70 sites were bound by Sp1 or Sp1-like proteins. Two other transcription elements, the ATF-80 and AP1-40 sites, may play a role in p40 activity. Mutation of these elements resulted in a modest decrease in p40 transcription, but DNA binding experiments did not clearly demonstrate binding of transcription factors to these sites. In contrast, a major late transcription factor site at -110 was shown to bind the transcription factor, but mutation of this site had no effect on p40 activity. In a previous report, we have shown that transactivation of the p40 promoter by the viral Rep proteins required an upstream Rep binding element (in the terminal repeat or the p5 promoter), an unidentified p19 promoter element, and a p40 promoter element (D. J. Pereira and N. Muzyczka, J. Virol. 71:1747-1756, 1997). Here we demonstrate that the CArG-140 element in the p19 promoter and the Sp1-50 element in the p40 promoter are the specific p19 and p40 elements required for Rep induction of p40. As in the case of the p19 promoter, Sp1 facilitates interaction of Rep with the p40 promoter by interaction of the two proteins. Furthermore, electron microscopy experiments demonstrated that when Rep is bound to an upstream Rep binding element, it can interact with a proximal Sp1 site by protein contacts and create a loop in the intervening DNA. This finding suggests a common mechanism whereby the Rep binding element in the TR or the p5 promoter induces p19 and p40 activity by interaction with their respective Sp1 sites.

Pereira, D J; Muzyczka, N

1997-01-01

101

Is video-game playing a risk factor for pathological gambling in Australian adolescents?  

PubMed

Very little research has been conducted to examine the relationship between video-game playing and gambling in adolescence. In this study, 2,669 adolescents aged 13-17 years were surveyed to obtained details of their involvement in gambling and video-game playing as well as a measure of pathological gambling (the DSM-IV-J). The results showed that, the frequency of video game playing was significantly related to pathological gambling, but that the effect size was very small and largely accounted for by the greater popularity of both activities amongst boys. There was some evidence for stronger associations between technologically similar activities, namely arcade video games and an interest in gaming machines, but other factors discussed in the paper may also account for this association. In summary, the findings suggested that playing video-games is unlikely to be a significant risk factor for pathological gambling during adolescence. PMID:19578983

Delfabbro, Paul; King, Daniel; Lambos, Chrisi; Puglies, Stan

2009-07-04

102

Vascular Endothelial Growth Factor Induction by Prostaglandin E 2 in Human Airway Smooth Muscle Cells Is Mediated by E Prostanoid EP 2 \\/EP 4 Receptors and SP1 Transcription Factor Binding Sites  

Microsoft Academic Search

Prostaglandin E2 (PGE2) can increase vascular endo- thelial growth factor A (VEGF-A) production but the mechanisms involved are unclear. Here we character- ized the transcriptional mechanisms involved in human airway smooth muscle cells (HASMC). PGE2 increased VEGF-A mRNA and protein but not mRNA stability. PGE2 stimulated the activity of a transiently transfected 2068-bp (2018 to 50) VEGF-A promoter-driven lucifer- ase

Dawn Bradbury; Deborah Clarke; Claire Seedhouse; Lisa Corbett; Joanne Stocks; Alan Knox

2005-01-01

103

A high expression level of insulin-like growth factor I receptor is associated with increased expression of transcription factor Sp1 and regional lymph node metastasis of human gastric cancer  

Microsoft Academic Search

Insulin-like growth factor I receptor (IGF-IR) is critical to cell survival and growth and altered IGF-IR expression is found in many human cancers. However, its expression and potential role in gastric cancer development and progression has not been explored. The IGF-IR expression level was determined via immunohistochemistry in primary tumor and lymph node metastasis of 86 cases of resected gastric

Yixing Jiang; Liwei Wang; Weida Gong; Daoyan Wei; Xiangdong Le; James Yao; Jaffer Ajani; James L. Abbruzzese; Suyun Huang; Keping Xie

2005-01-01

104

Transcriptional Activation of REST by Sp1 in Huntington's Disease Models  

PubMed Central

In Huntington's disease (HD), mutant huntingtin (mHtt) disrupts the normal transcriptional program of disease neurons by altering the function of several gene expression regulators such as Sp1. REST (Repressor Element-1 Silencing Transcription Factor), a key regulator of neuronal differentiation, is also aberrantly activated in HD by a mechanism that remains unclear. Here, we show that the level of REST mRNA is increased in HD mice and in NG108 cells differentiated into neuronal-like cells and expressing a toxic mHtt fragment. Using luciferase reporter gene assay, we delimited the REST promoter regions essential for mHtt-mediated REST upregulation and found that they contain Sp factor binding sites. We provide evidence that Sp1 and Sp3 bind REST promoter and interplay to fine-tune REST transcription. In undifferentiated NG108 cells, Sp1 and Sp3 have antagonistic effect, Sp1 acting as an activator and Sp3 as a repressor. Upon neuronal differentiation, we show that the amount and ratio of Sp1/Sp3 proteins decline, as does REST expression, and that the transcriptional role of Sp3 shifts toward a weak activator. Therefore, our results provide new molecular information to the transcriptional regulation of REST during neuronal differentiation. Importantly, specific knockdown of Sp1 abolishes REST upregulation in NG108 neuronal-like cells expressing mHtt. Our data together with earlier reports suggest that mHtt triggers a pathogenic cascade involving Sp1 activation, which leads to REST upregulation and repression of neuronal genes.

Ravache, Myriam; Weber, Chantal; Merienne, Karine; Trottier, Yvon

2010-01-01

105

Transcriptional activation of REST by Sp1 in Huntington's disease models.  

PubMed

In Huntington's disease (HD), mutant huntingtin (mHtt) disrupts the normal transcriptional program of disease neurons by altering the function of several gene expression regulators such as Sp1. REST (Repressor Element-1 Silencing Transcription Factor), a key regulator of neuronal differentiation, is also aberrantly activated in HD by a mechanism that remains unclear. Here, we show that the level of REST mRNA is increased in HD mice and in NG108 cells differentiated into neuronal-like cells and expressing a toxic mHtt fragment. Using luciferase reporter gene assay, we delimited the REST promoter regions essential for mHtt-mediated REST upregulation and found that they contain Sp factor binding sites. We provide evidence that Sp1 and Sp3 bind REST promoter and interplay to fine-tune REST transcription. In undifferentiated NG108 cells, Sp1 and Sp3 have antagonistic effect, Sp1 acting as an activator and Sp3 as a repressor. Upon neuronal differentiation, we show that the amount and ratio of Sp1/Sp3 proteins decline, as does REST expression, and that the transcriptional role of Sp3 shifts toward a weak activator. Therefore, our results provide new molecular information to the transcriptional regulation of REST during neuronal differentiation. Importantly, specific knockdown of Sp1 abolishes REST upregulation in NG108 neuronal-like cells expressing mHtt. Our data together with earlier reports suggest that mHtt triggers a pathogenic cascade involving Sp1 activation, which leads to REST upregulation and repression of neuronal genes. PMID:21179468

Ravache, Myriam; Weber, Chantal; Mérienne, Karine; Trottier, Yvon

2010-12-14

106

The proximal GC-rich region of p16 INK4a gene promoter plays a role in its transcriptional regulation  

Microsoft Academic Search

p16INK4a plays a key role in control of cell cycle progression by negatively regulating the CDK4\\/6 activity. This study establishes\\u000a that the p16INK4a minimal promoter region required for the transcription factor Sp1 function is mapped at 62 bp upstream of the translation\\u000a initiation codon. This region is GC-rich and shown to interact specifically with Sp1. siRNA-induced Sp1 silencing resulted\\u000a in the

Xiuli Wang; Yunpeng Feng; Lina Pan; Yanle Wang; Xin Xu; Jun Lu; Baiqu Huang

2007-01-01

107

The human–canine environment: A risk factor for non-play bites?  

Microsoft Academic Search

Few dog bite risk factor studies have been conducted. This veterinary clinic-based retrospective cohort study was aimed at identifying human–canine environmental risk factors for non-play bites in Kingston, Jamaica (660) and San Francisco (SF), USA (452). Data were analysed using modified Poisson regression with confounders selected using directed acyclic graphs (DAGs) and the change-in-estimate procedure.Dogs acquired for companionship were more

Locksley L. Mc V. Messam; Philip H. Kass; Bruno B. Chomel; Lynette A. Hart

2008-01-01

108

Risk Factors in Adolescence: The Case of Gambling, Videogame Playing, and the Internet  

Microsoft Academic Search

It has been noted that adolescents may be more susceptible to pathological gambling. Not only is it usually illegal, but it appears to be related to high levels of problem gambling and other delinquent activities such as illicit drug taking and alcohol abuse. This paper examines risk factors not only in adolescent gambling but also in videogame playing (which shares

Mark Griffiths; Richard T. A. Wood

2000-01-01

109

Hepatitis B virus X protein upregulates Lin28A/Lin28B through Sp-1/c-Myc to enhance the proliferation of hepatoma cells.  

PubMed

Hepatitis B virus X protein (HBx) plays critical roles in the pathogenesis of hepatocellular carcinoma (HCC). Here, we were interested in knowing whether the oncogene Lin28A and its homolog Lin28B are involved in the hepatocarcinogenesis mediated by HBx. We showed that the expression levels of Lin28A and Lin28B were increased in clinical HCC tissues, HepG2.2.15 cell line and liver tissues of p21-HBx transgenic mice. Interestingly, the expression levels of HBx were positively associated with those of Lin28A/Lin28B in clinical HCC tissues. Moreover, the overexpression of HBx resulted in the upregulation of Lin28A/Lin28B in hepatoma HepG2/H7402 cell lines by transient transfection, suggesting that HBx was able to upregulate Lin28A and Lin28B. Then, we examined the mechanism by which HBx upregulated Lin28A and Lin28B. We identified that the promoter region of Lin28A regulated by HBx was located at nt -235/-66 that contained Sp-1 binding element. Co-immunoprecipitation showed that HBx was able to interact with Sp-1 in HepG2-X cells. Moreover, chromatin immunoprecipitation (ChIP) demonstrated that HBx could bind to the promoter of Lin28A, which failed to work when Sp-1 was silenced. Electrophoretic mobility shift assay (EMSA) further identified that HBx was able to interact with Sp-1 element in Lin28A promoter via transcription factor Sp-1. In addition, we found that c-Myc was involved in the activation of Lin28B mediated by HBx. In function, Lin28A/Lin28B played important roles in HBx-enhanced proliferation of hepatoma cells in vitro and in vivo. In conclusion, HBx activates Lin28A/Lin28B through Sp-1/c-Myc in hepatoma cells. Lin28A/Lin28B serves as key driver genes in HBx-induced hepatocarcinogenesis.Oncogene advance online publication, 14 January 2013; doi:10.1038/onc.2012.618. PMID:23318446

You, X; Liu, F; Zhang, T; Lv, N; Liu, Q; Shan, C; Du, Y; Kong, G; Wang, T; Ye, L; Zhang, X

2013-01-14

110

Growth factor delivery methods in the management of sports injuries: the state of play.  

PubMed

In recent years there have been rapid developments in the use of growth factors for accelerated healing of injury. Growth factors have been used in maxillo-facial and plastic surgery with success and the technology is now being developed for orthopaedics and sports medicine applications. Growth factors mediate the biological processes necessary for repair of soft tissues such as muscle, tendon and ligament following acute traumatic or overuse injury, and animal studies have demonstrated clear benefits in terms of accelerated healing. There are various ways of delivering higher doses of growth factors to injured tissue, but each has in common a reliance on release of growth factors from blood platelets. Platelets contain growth factors in their alpha-granules (insulin-like growth factor-1, basic fibroblast growth factor, platelet-derived growth factor, epidermal growth factor, vascular endothelial growth factor, transforming growth factor-beta(1)) and these are released upon injection at the site of an injury. Three commonly utilised techniques are known as platelet-rich plasma, autologous blood injections and autologous conditioned serum. Each of these techniques has been studied clinically in humans to a very limited degree so far, but results are promising in terms of earlier return to play following muscle and particularly tendon injury. The use of growth factors in sports medicine is restricted under the terms of the World Anti-Doping Agency (WADA) anti-doping code, particularly because of concerns regarding the insulin-like growth factor-1 content of such preparations, and the potential for abuse as performance-enhancing agents. The basic science and clinical trials related to the technology are reviewed, and the use of such agents in relation to the WADA code is discussed. PMID:17984193

Creaney, L; Hamilton, B

2007-11-05

111

O-linkage of N-acetylglucosamine to Sp1 activation domain inhibits its transcriptional capability  

PubMed Central

The posttranslational modification of eukaryotic intracellular proteins by O-linked N-acetylglucosamine (O-GlcNAc) monosaccharides is essential for cell viability, yet its precise functional roles are largely unknown. O-GlcNAc transferase utilizes UDP-GlcNAc, the end product of hexosamine biosynthesis, to catalyze this modification. The availability of UDP-GlcNAc correlates with glycosylation levels of intracellular proteins as well as with transcriptional levels of some genes. Meanwhile, transcription factors and RNA polymerase II can be modified by O-GlcNAc. A linkage between transcription factor O-GlcNAcylation and transcriptional regulation therefore has been postulated. Here, we show that O-GlcNAcylation of a chimeric transcriptional activator containing the second activation domain of Sp1 decreases its transcriptional activity both in an in vitro transcription system and in living cells, which is in concert with our observation that O-GlcNAcylation of Sp1 activation domain blocks its in vitro and in vivo interactions with other Sp1 molecules and TATA-binding protein-associated factor II 110. Furthermore, overexpression of O-GlcNAc transferase specifically inhibits transcriptional activation by native Sp1 in cells. Thus, our studies provide direct evidence that O-GlcNAcylation of transcription factors is involved in transcriptional regulation.

Yang, Xiaoyong; Su, Kaihong; Roos, Mark D.; Chang, Qing; Paterson, Andrew J.; Kudlow, Jeffrey E.

2001-01-01

112

Heat stress protection in Aspen sp1 transgenic Arabidopsis thaliana.  

PubMed

It is known that the stable protein 1 (SP1) detected in aspen plants remains soluble upon boiling and that sp1 expression in transgenic aspen is resistant to salt stress. Presently, we analyzed the effect of expression of SP1 in Arabidopsis thaliana plants and their response to high temperature stress. After 45 degrees C for 16 h, relative to wild type plants, sp1 transgenic plants exhibited stronger growth and were better in several physiological properties including chlorophyll, chlorophyll fluorescence, water content, proline content, and malondialdehyde content. These preliminarily results suggest that the over-expression of SP1 may notably enhance heat-tolerant level of transgenic A. thaliana plants. PMID:18510869

Zhu, Bo; Xiong, Ai-Sheng; Peng, Ri-He; Xu, Jing; Zhou, Jun; Xu, Jin-Tao; Jin, Xiao-Fen; Zhang, Yang; Hou, Xi-Lin; Yao, Quan-Hong

2008-05-31

113

A microfluidic-FCS platform for investigation on the dissociation of Sp1DNA complex by doxorubicin  

Microsoft Academic Search

The transcription factor (TF) Sp1 is a well-known RNA polymerase II transcription activator that binds to GC-rich recognition sites in a number of essential cellular and viral promoters. In addition, direct inter- ference of Sp1 binding to DNA cognate sites using DNA-interacting compounds may provide promising therapies for suppression of cancer progression and viral replication. In this study, we present

Hsin-Chih Yeh; Christopher M. Puleo; Teck Chuan Lim; Yi-Ping Ho; Paul E. Giza; R. C. C. Huang; T.-H. Wang

2006-01-01

114

PPARbeta/delta regulates the human SIRT1 gene transcription via Sp1.  

PubMed

NAD-dependent deacetylase SIRT1 is known to be activated by caloric restriction and is related to longevity. A natural polyphenolic compound resveratrol is also shown to increases SIRT1 activity and extends lifespan. However, the transcriptional regulation of SIRT1 gene has not completely examined in the context of metabolism. Thus, in this study, we characterized the 5' -flanking region of human SIRT1 gene. We first found that representative metabolic hormones and related factors (glucocorticoid, glucagon/cAMP, and insulin) did not show significant effect on SIRT1 gene transcription. PPARalpha and PPARgamma1 without/with their specific ligands did not have significant effect as well. In contrast, expression of PPARbeta/delta (PPARdelta markedly increased the 5' -promoter activity of SIRT1 gene, which was further amplified by the addition of GW501516, a selective PPARdelta agonist. Deletion/mutation mapping analyses failed to identify PPAR binding element but revealed the presence of canonical Sp1 binding site, which was conserved among species. The Sp1 site is functional, because Sp1 overexpresson significantly enhanced SIRT1 promoter activity, and the binding of Sp1 to the element was confirmed by EMSA and ChIP assays. Interestingly, specific Sp1 antagonist mithramycin completely abolished the PPARdelta-mediated induction of SIRT1 gene transcription. Altogether, our data suggest the predominant role of PPARdelta in the transcriptional regulation of SIRT1 gene. Furthermore, the effects of PPARdelta seem to be mediated by Sp1. We assume that, in vivo, starvation increases lipolysis-derived free fatty acid and activates PPARdelta and the resultant increase in SIRT1 expression, in addition to the activation by NAD and AMPK, facilitates the deacetylation of a variety of proteins involved in mitochondrial beta-oxidation pathway and cell survival. PMID:20160399

Okazaki, Mizuho; Iwasaki, Yasumasa; Nishiyama, Mitsuru; Taguchi, Takafumi; Tsugita, Makoto; Nakayama, Shuichi; Kambayashi, Machiko; Hashimoto, Kozo; Terada, Yoshio

2010-02-17

115

Risk factors in adolescence: the case of gambling, videogame playing, and the internet.  

PubMed

It has been noted that adolescents may be more susceptible to pathological gambling. Not only is it usually illegal, but it appears to be related to high levels of problem gambling and other delinquent activities such as illicit drug taking and alcohol abuse. This paper examines risk factors not only in adolescent gambling but also in videogame playing (which shares many similarities with gambling). There appear to be three main forms of adolescent gambling that have been widely researched. Adolescent gambling activities and general risk factors in adolescent gambling are provided. As well, the influence of technology on adolescents in the form of both videogames and the Internet are examined. It is argued that technologically advanced forms of gambling may be highly appealing to adolescents. PMID:14634313

Griffiths, M; Wood, R T

2000-01-01

116

Transactivation of the human NME5 gene by Sp1 in pancreatic cancer cells.  

PubMed

Non-metastatic cells 5 (NME5), a recently found gene belonging to the NDPK-like molecules gene family, is highly expressed in testis and some types of human cancer. Current studies have revealed diverse potential functions of NME5 and we have reported that NME5 is associated with innate resistance to gemcitabine in human pancreatic cancer cells in previous study. However, the mechanism underlying the transcriptional regulation of NME5 has not been elucidated yet. In this study, we analyzed the 5'-flanking region of the human NME5 gene and revealed its transcription start site (TSS) at -35 bp relative to its translation start codon ATG. Using 5' unidirectional deletion analysis, we demonstrated that the proximal promoter of NME5 is located within -1051 bp to +35 bp. Two functional GC-boxes (-300 bp and -323 bp) were identified within the promoter region. Mutation of either GC-box led to significant reduction in NME5 promoter activity, whereas overexpression of Sp1 activated NME5 promoter activity in MIA PaCa-2 and 293T cells. In silico analysis predicted that transcription factor Sp1 binds to both GC-boxes, which were confirmed by EMSA and ChIP. In addition, we found that compared with MIA PaCa-2, Sp1 was highly expressed in PAXC002, a well characterized human pancreatic cancer cell line with innate gemcitabine resistance where NME5 was reported to be highly expressed, indicating that Sp1 induces NEM5 expression in PAXC002 cells. In conclusion, our study characterized for the first time the human NME5 promoter which is controlled by Sp1 transcription factor in pancreatic cancer. PMID:22564704

Li, Fu; Jiang, Zhenzhou; Wang, Ke; Guo, Jingjing; Hu, Gang; Sun, Lixin; Wang, Tao; Tang, Xuzhen; He, Ling; Yao, Jincheng; Wen, Danyi; Qin, Xiaoran; Zhang, Luyong

2012-05-04

117

Mechanical factors play an important role in pectus excavatum with thoracic scoliosis  

PubMed Central

Background This study investigated the incidence, imaging characteristics and mechanical factors in scoliotic patients with pectus excavatum. Methods A total of 142 scoliostic patients with pectus excavatum were evaluated prior to operation. The evaluation included a complete physical exam, phenotype and severity of the pectus excavatum, incidence and severity of scoliosis, and analysis of radiological images, including calculation of the Haller index. Results Twenty five out of 142 patients (17.61%) with pectus excavatum had scoliosis with a Cobb angle >10 degrees, and in 80.00% of the cases the spinal column was bent to the right. Seventeen patients had bent-to-the-right spines that involved the 6th to 10 th thoracic vertebrae. We found that 23 out of 25 patients with a Cobb angle more than 10° were teenagers and adults. The incidence of scoliosis was only 6.06% in the children under 11 years whereas it was 21.79% in the teenage group. Conclusions Mechanical forces appear to play a role in the coexistence of pectus excavatum and scoliosis. There is a relationship between age, severity (Haller index), asymmetry and scoliosis. The heart and mediastinum play a role in providing an outward force to the left of the sternum which may be an important reason for the coexistence of pectus excavatum and scoliosis, but the correlation needs further proof.

2012-01-01

118

Hypoxia-inducible factor plays a gut-injurious role in intestinal ischemia reperfusion injury  

PubMed Central

Gut injury and loss of normal intestinal barrier function are key elements in the paradigm of gut-origin systemic inflammatory response syndrome, acute lung injury, and multiple organ dysfunction syndrome (MODS). As hypoxia-inducible factor (HIF-1) is a critical determinant of the physiological and pathophysiological response to hypoxia and ischemia, we asked whether HIF-1 plays a proximal role in the induction of gut injury and subsequent lung injury. Using partially HIF-1?-deficient mice in an isolated superior mesenteric artery occlusion (SMAO) intestinal ischemia reperfusion (I/R) injury model (45 min SMAO followed by 3 h of reperfusion), we showed a direct relationship between HIF-1 activation and intestinal I/R injury. Specifically, partial HIF-1? deficiency attenuated SMAO-induced increases in intestinal permeability, lipid peroxidation, mucosal caspase-3 activity, and IL-1? mRNA levels. Furthermore, partial HIF-1? deficiency prevented the induction of ileal mucosal inducible nitric oxide synthase (iNOS) protein levels after SMAO and iNOS deficiency ameliorated SMAO-induced villus injury. Resistance to SMAO-induced gut injury was also associated with resistance to lung injury, as reflected by decreased levels of myeloperoxidase, IL-6 and IL-10 in the lungs of HIF-1?+/? mice. In contrast, a short duration of SMAO (15 min) followed by 3 h of reperfusion neither induced mucosal HIF-1? protein levels nor caused significant gut and lung injury in wild-type or HIF-1?+/? mice. This study indicates that intestinal HIF-1 activation is a proximal regulator of I/R-induced gut mucosal injury and gut-induced lung injury. However, the duration and severity of the gut I/R insult dictate whether HIF-1 plays a gut-protective or deleterious role.

Kannan, Kolenkode B.; Colorado, Iriana; Reino, Diego; Palange, David; Lu, Qi; Qin, Xiaofa; Abungu, Billy; Watkins, Anthony; Caputo, Francis J.; Xu, Da-Zhong; Semenza, Gregg L.; Deitch, Edwin A.

2011-01-01

119

Specificity protein 1 (sp1) oscillation is involved in copper homeostasis maintenance by regulating human high-affinity copper transporter 1 expression.  

PubMed

Copper is an essential micronutrient for cell growth but is toxic in excess. Copper transporter (Ctr1) plays an important role in regulating adequate copper levels in mammalian cells. We have shown previously that expression of the human high-affinity copper transporter (hCtr1) was transcriptionally up-regulated under copper-depleted conditions and down-regulated under replete conditions; moreover, elevated hCtr1 levels suppress hCtr1 expression. Specificity protein 1 (Sp1) regulates expression of hCtr1 under copper-stressed conditions. In this study, we made the following important observations: 1) Sp1 expression is down-regulated under copper-replete conditions but up-regulated under copper-depleted conditions. These up- and down-regulations of Sp1 in turn regulate hCtr1 expression to control copper homeostasis. 2) Copper-regulated Sp1 expression involved Sp1 binding to its own promoter as demonstrated by the chromatin immunoprecipitation assay; therefore, Sp1 is also transcriptionally self-regulated via hCtr1/copper intermediation. 3) Both zinc finger and glutamine-rich transactivation domains of Sp1 are involved in the Sp1-mediated hCtr1 and Sp1 regulation by copper stresses. 4) Although Sp3 expression is also regulated by copper availability, Sp3 does not regulate hCtr1 homeostasis. Collectively, our results demonstrated that mammalian cells use Sp1 oscillation in response to copper availability to regulate copper homeostasis through hCtr1 expression in a tripartite inter-regulatory relationship. These findings have important implications in mammalian copper physiology regulation. PMID:22172574

Liang, Zheng D; Tsai, Wen-Bin; Lee, Mei-Yi; Savaraj, Niramol; Kuo, Macus Tien

2011-12-15

120

Specificity Protein 1 (Sp1) Oscillation Is Involved in Copper Homeostasis Maintenance by Regulating Human High-Affinity Copper Transporter 1 Expression  

PubMed Central

Copper is an essential micronutrient for cell growth but is toxic in excess. Copper transporter (Ctr1) plays an important role in regulating adequate copper levels in mammalian cells. We have shown previously that expression of the human high-affinity copper transporter (hCtr1) was transcriptionally up-regulated under copper-depleted conditions and down-regulated under replete conditions; moreover, elevated hCtr1 levels suppress hCtr1 expression. Specificity protein 1 (Sp1) regulates expression of hCtr1 under copper-stressed conditions. In this study, we made the following important observations: 1) Sp1 expression is down-regulated under copper-replete conditions but up-regulated under copper-depleted conditions. These up- and down-regulations of Sp1 in turn regulate hCtr1 expression to control copper homeostasis. 2) Copper-regulated Sp1 expression involved Sp1 binding to its own promoter as demonstrated by the chromatin immunoprecipitation assay; therefore, Sp1 is also transcriptionally self-regulated via hCtr1/copper intermediation. 3) Both zinc finger and glutamine-rich transactivation domains of Sp1 are involved in the Sp1-mediated hCtr1 and Sp1 regulation by copper stresses. 4) Although Sp3 expression is also regulated by copper availability, Sp3 does not regulate hCtr1 homeostasis. Collectively, our results demonstrated that mammalian cells use Sp1 oscillation in response to copper availability to regulate copper homeostasis through hCtr1 expression in a tripartite inter-regulatory relationship. These findings have important implications in mammalian copper physiology regulation.

Liang, Zheng D.; Tsai, Wen-Bin; Lee, Mei-Yi; Savaraj, Niramol

2012-01-01

121

Transcriptional Activation of REST by Sp1 in Huntington's Disease Models  

Microsoft Academic Search

In Huntington's disease (HD), mutant huntingtin (mHtt) disrupts the normal transcriptional program of disease neurons by altering the function of several gene expression regulators such as Sp1. REST (Repressor Element-1 Silencing Transcription Factor), a key regulator of neuronal differentiation, is also aberrantly activated in HD by a mechanism that remains unclear. Here, we show that the level of REST mRNA

Myriam Ravache; Chantal Weber; Karine Mérienne; Yvon Trottier; Mel B. Feany

2010-01-01

122

Regulation of transcription of the human erythropoietin receptor gene by proteins binding to GATA-1 and Sp1 motifs.  

PubMed Central

Erythropoietin (Epo), the primary regulator of the production of erythroid cells, acts by binding to a cell surface receptor (EpoR) on erythroid progenitors. We used deletion analysis and transfection assays with reporter gene constructs to examine the transcription control elements in the 5' flanking region of the human EpoR gene. In erythroid cells most of the transcription activity was contained in a 150 bp promoter fragment with binding sites for transcription factors AP2, Sp1 and the erythroid-specific GATA-1. The 150 bp hEpoR promoter exhibited high and low activity in erythroid OCIM1 and K562 cells, respectively, reflecting the high and low levels of constitutive hEpoR expression. The GATA-1 and Sp1 binding sites in this promoter lacking a TATA sequence were necessary for a high level of transcription activation. Protein-DNA binding studies suggested that Sp1 and two other CCGCCC binding proteins from erythroid and non-erythroid cells could bind to the Sp1 binding motif. By increasing GATA-1 levels via co-transfection, we were able to transactivate the hEpoR promoter in K562 cells and non-erythroid cells, but not in the highly active OCIM1 cells, although GATA-1 mRNA levels were comparable in OCIM1 and K562. Interestingly, when we mutated the Sp1 site, resulting in a marked decrease in hEpoR promoter activity, we could restore transactivation by increasing GATA-1 levels in OCIM1 cells. These data suggest that while GATA-1 can transactivate the EpoR promoter, the level of hEpoR gene expression does not depend on GATA-1 alone. Rather, hEpoR transcription activity depends on coordination between Sp1 and GATA-1 with other cell-specific factors, including possibly other Sp1-like binding proteins, to provide high level, tissue-specific expression. Images

Chin, K; Oda, N; Shen, K; Noguchi, C T

1995-01-01

123

A Role for Sp1 in Transcriptional Regulation of Phosphatidylethanolamine N-Methyltransferase in Liver and 3T3-L1 Adipocytes*  

PubMed Central

Phosphatidylcholine is made in all nucleated mammalian cells via the CDP-choline pathway. Another major pathway for phosphatidylcholine biosynthesis in liver is catalyzed by phosphatidylethanolamine N-methyltransferase (PEMT). We have now identified 3T3-L1 adipocytes as a cell culture model that expresses PEMT endogenously. We have found that PEMT mRNA and protein levels increased dramatically in 3T3-L1 cells upon differentiation to adipocytes. 5?-Deletion analysis of the PEMT promoter-luciferase constructs stably expressed in 3T3-L1 adipocytes identified a regulatory region between ?471 and ?371 bp (relative to the transcriptional start site). Competitive and supershift assays demonstrated binding sites for transcription factors Sp1, Sp3 (?408 to ?413), and YY1 (?417 to ?420). During differentiation of 3T3-L1 cells to adipocytes, the amount of Sp1 protein decreased by ?50% just prior to activation of PEMT. Transduction of 3T3-L1 adipocytes with retrovirus containing Sp1 cDNA demonstrated that Sp1 inhibited PEMT transcriptional activity. Similarly, short hairpin RNA directed against Sp1 in 3T3-L1 adipocytes enhanced PEMT transcriptional activation. Chromatin immunoprecipitation assays confirmed that Sp1 binds to the PEMT promoter, and this interaction decreases upon differentiation to adipocytes. These experiments directly link increased PEMT expression in adipocytes to decreased transcriptional expression of Sp1. In addition, our data established that Sp1 binding was required for tamoxifen-mediated inhibition of Pemt promoter activity.

Cole, Laura K.; Vance, Dennis E.

2010-01-01

124

Transcription factor ets-2 plays an important role in the pathogenesis of pulmonary fibrosis.  

PubMed

Ets-2 is a ubiquitous transcription factor activated after phosphorylation at threonine-72. Previous studies highlighted the importance of phosphorylated ets-2 in lung inflammation and extracellular matrix remodeling, two pathways involved in pulmonary fibrosis. We hypothesized that phosphorylated ets-2 played an important role in pulmonary fibrosis, and we sought to determine the role of ets-2 in its pathogenesis. We challenged ets-2 (A72/A72) transgenic mice (harboring a mutated form of ets-2 at phosphorylation site threonine-72) and ets-2 (wild-type/wild-type [WT/WT]) control mice with sequential intraperitoneal injections of bleomycin, followed by quantitative measurements of lung fibrosis and inflammation and primary cell in vitro assays. Concentrations of phosphorylated ets-2 were detected via the single and dual immunohistochemical staining of murine lungs and lung sections from patients with idiopathic pulmonary fibrosis. Ets-2 (A72/A72) mice were protected from bleomycin-induced pulmonary fibrosis, compared with ets-2 (WT/WT) mice. This protection was characterized by decreased lung pathological abnormalities and the fibrotic gene expression of Type I collagen, Type III collagen, ?-smooth muscle actin, and connective tissue growth factor. Immunohistochemical staining of lung sections from bleomycin-treated ets-2 (WT/WT) mice and from patients with idiopathic pulmonary fibrosis demonstrated increased staining of phosphorylated ets-2 that colocalized with Type I collagen expression and to fibroblastic foci. Lastly, primary lung fibroblasts from ets-2 (A72/A72) mice exhibited decreased expression of Type I collagen in response to stimulation with TGF-?, compared with fibroblasts from ets-2 (WT/WT) mice. These data indicate the importance of phosphorylated ets-2 in the pathogenesis of pulmonary fibrosis through the expression of Type I collagen and (myo)fibroblast activation. PMID:21562315

Baran, Christopher P; Fischer, Sara N; Nuovo, Gerard J; Kabbout, Mohamed N; Hitchcock, Charles L; Bringardner, Benjamin D; McMaken, Sara; Newland, Christie A; Cantemir-Stone, Carmen Z; Phillips, Gary S; Ostrowski, Michael C; Marsh, Clay B

2011-05-11

125

Transcription Factor ets-2 Plays an Important Role in the Pathogenesis of Pulmonary Fibrosis  

PubMed Central

Ets-2 is a ubiquitous transcription factor activated after phosphorylation at threonine-72. Previous studies highlighted the importance of phosphorylated ets-2 in lung inflammation and extracellular matrix remodeling, two pathways involved in pulmonary fibrosis. We hypothesized that phosphorylated ets-2 played an important role in pulmonary fibrosis, and we sought to determine the role of ets-2 in its pathogenesis. We challenged ets-2 (A72/A72) transgenic mice (harboring a mutated form of ets-2 at phosphorylation site threonine-72) and ets-2 (wild-type/wild-type [WT/WT]) control mice with sequential intraperitoneal injections of bleomycin, followed by quantitative measurements of lung fibrosis and inflammation and primary cell in vitro assays. Concentrations of phosphorylated ets-2 were detected via the single and dual immunohistochemical staining of murine lungs and lung sections from patients with idiopathic pulmonary fibrosis. Ets-2 (A72/A72) mice were protected from bleomycin-induced pulmonary fibrosis, compared with ets-2 (WT/WT) mice. This protection was characterized by decreased lung pathological abnormalities and the fibrotic gene expression of Type I collagen, Type III collagen, ?–smooth muscle actin, and connective tissue growth factor. Immunohistochemical staining of lung sections from bleomycin-treated ets-2 (WT/WT) mice and from patients with idiopathic pulmonary fibrosis demonstrated increased staining of phosphorylated ets-2 that colocalized with Type I collagen expression and to fibroblastic foci. Lastly, primary lung fibroblasts from ets-2 (A72/A72) mice exhibited decreased expression of Type I collagen in response to stimulation with TGF-?, compared with fibroblasts from ets-2 (WT/WT) mice. These data indicate the importance of phosphorylated ets-2 in the pathogenesis of pulmonary fibrosis through the expression of Type I collagen and (myo)fibroblast activation.

Baran, Christopher P.; Fischer, Sara N.; Nuovo, Gerard J.; Kabbout, Mohamed N.; Hitchcock, Charles L.; Bringardner, Benjamin D.; McMaken, Sara; Newland, Christie A.; Cantemir-Stone, Carmen Z.; Phillips, Gary S.; Ostrowski, Michael C.

2011-01-01

126

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

PubMed Central

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

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

2012-01-01

127

Krüppel-like factor 12 plays a significant role in poorly differentiated gastric cancer progression.  

PubMed

Gastric cancer is the second common malignant neoplasia in Japan, and its poorly differentiated form is a deadly disease. To identify novel candidate oncogenes contributing to its genesis, we examined copy-number alterations in 50 primary poorly differentiated gastric cancers using an array-based comparative genomic hybridization (array-CGH). Many genetic changes were identified, including a novel amplification of the 13q22 locus. Several genes are located in this locus, and selective knockdown of one for the Krüppel-like factor 12 (KLF12) induced significant growth-arrest in the HGC27 gastric cancer cell line. Microarray analysis also demonstrated that genes associated with cell proliferation were mostly changed by KLF12 knockdown. To explore the oncogenic function of KLF12, we introduced a full length of human KLF12 cDNA into NIH3T3 and AZ-521 cell lines and found that overexpression significantly enhanced their invasive potential. In clinical samples, KLF12 mRNA in cancer tissue was increased in 11 of 28 cases (39%) when compared with normal gastric epithelium. Clinicopathological analysis further demonstrated a significant correlation between KLF12mRNA levels and tumor size (p = 0.038). These data suggest that the KLF12 gene plays an important role in poorly differentiated gastric cancer progression and is a potential target of therapeutic measures. PMID:19588488

Nakamura, Yu; Migita, Toshiro; Hosoda, Fumie; Okada, Naoko; Gotoh, Masahiro; Arai, Yasuhito; Fukushima, Michiyo; Ohki, Misao; Miyata, Satoshi; Takeuchi, Kengo; Imoto, Issei; Katai, Hitoshi; Yamaguchi, Toshiharu; Inazawa, Johji; Hirohashi, Setsuo; Ishikawa, Yuichi; Shibata, Tatsuhiro

2009-10-15

128

p53 Represses Transcription of RING Finger LIM Domain-Binding Protein RLIM through Sp1  

PubMed Central

RLIM acts as a negative regulator of LIM-Homeodomain proteins either by recruiting Sin3A/Histone Deacetylase (HDAC) co-repressor complex or through degradation of CLIM coactivator, thus playing an important role in embryonic development. Recent studies by different research groups have shown that RLIM acts as an X-encoded, dose-dependent inducer of X chromosome inactivation in mouse embryonic stem cells. However, until now, very little is known about the expression regulation of RLIM gene, and we tried to study the transctriptional regulation of RLIM gene. In the present study, we identified RLIM as a novel target of p53 and demonstrated that p53 repressed both mRNA and protein levels of RLIM. Expression of wild type p53, but not p53 mutants, led to repression of the RLIM promoter activity. We further identified four putative Sp1 elements (S1 to S4) on the RLIM promoter that are essential for p53-mediated repression of RLIM. Although p53 does not directly bind to the RLIM promoter, it physically interacts with and prevents the binding of Sp1 to the RLIM promoter. Thus, RLIM is a novel target of p53, and p53 exerts its inhibitory effect on RLIM expression by interfering with Sp1-mediated transcriptional activation on RLIM. Our results provided data to enlarge the knowledge of transcriptional regulation of RLIM and suggested a new pathway by which physiological and pathological activators of p53 may affect development.

Zhang, Pingzhao; Qin, Bo; Han, Dingding; Wang, Chenji; Dang, Yongjun; Liu, Jun O.; Yu, Long

2013-01-01

129

The Factors of Design on Playing Equipment in Young Children Schools by Viewpoint of Young Children Behavioral Development  

ERIC Educational Resources Information Center

|The main purpose of this study was to explore the care-givers of preschool education institutions whose cognition on playing equipment functions, conditions of both setting and using, and the main factors which should beware of design. Besides, not only constructed the factors of design, but also provided suggestions about setting and designing…

Kuo, Chuen-tzay

2009-01-01

130

Platelet activating factor receptor binding plays a critical role in jet fuel-induced immune suppression.  

PubMed

Applying military jet fuel (JP-8) or commercial jet fuel (Jet-A) to the skin of mice suppresses the immune response in a dose-dependent manner. The release of biological response modifiers, particularly prostaglandin E2 (PGE2), is a critical step in activating immune suppression. Previous studies have shown that injecting selective cyclooxygenase-2 inhibitors into jet fuel-treated mice blocks immune suppression. Because the inflammatory phospholipid mediator, platelet-activating factor (PAF), up-regulates cyclooxygenase-2 production and PGE2 synthesis by keratinocytes, we tested the hypothesis that PAF-receptor binding plays a role in jet fuel-induced immune suppression. Treating keratinocyte cultures with PAF and/or jet fuel (JP-8 and Jet-A) stimulates PGE2 secretion. Jet fuel-induced PGE2 production was suppressed by treating the keratinocytes with specific PAF-receptor antagonists. Injecting mice with PAF, or treating the skin of the mice with JP-8, or Jet-A, induced immune suppression. Jet fuel-induced immune suppression was blocked when the jet fuel-treated mice were injected with PAF-receptor antagonists before treatment. Jet fuel treatment has been reported to activate oxidative stress and treating the mice with anti-oxidants (Vitamins C, or E or beta-hydroxy toluene), before jet fuel application, interfered with immune suppression. These findings confirm previous studies showing that PAF-receptor binding can modulate immune function. Furthermore, they suggest that PAF-receptor binding may be an early event in the induction of immune suppression by immunotoxic environmental agents that target the skin. PMID:15020195

Ramos, Gerardo; Kazimi, Nasser; Nghiem, Dat X; Walterscheid, Jeffrey P; Ullrich, Stephen E

2004-03-15

131

Bortezomib induces DNA hypomethylation and silenced gene transcription by interfering with Sp1/NF-kappaB-dependent DNA methyltransferase activity in acute myeloid leukemia.  

PubMed

Bortezomib reversibly inhibits 26S proteasomal degradation, interferes with NF-kappaB, and exhibits antitumor activity in human malignancies. Zinc finger protein Sp1 transactivates DNMT1 gene in mice and is functionally regulated through protein abundance, posttranslational modifications (ie, ubiquitination), or interaction with other transcription factors (ie, NF-kappaB). We hypothesize that inhibition of proteasomal degradation and Sp1/NF-kappaB-mediated transactivation may impair aberrant DNA methyltransferase activity. We show here that, in addition to inducing accumulation of polyubiquitinated proteins and abolishment of NF-kappaB activities, bortezomib decreases Sp1 protein levels, disrupts the physical interaction of Sp1/NF-kappaB, and prevents binding of the Sp1/NF-kappaB complex to the DNMT1 gene promoter. Abrogation of Sp1/NF-kappaB complex by bortezomib causes transcriptional repression of DNMT1 gene and down-regulation of DNMT1 protein, which in turn induces global DNA hypomethylation in vitro and in vivo and re-expression of epigenetically silenced genes in human cancer cells. The involvement of Sp1/NF-kappaB in DNMT1 regulation is further demonstrated by the observation that Sp1 knockdown using mithramycin A or shRNA decreases DNMT1 protein levels, which instead are increased by Sp1 or NF-kappaB overexpression. Our results unveil the Sp1/NF-kappaB pathway as a modulator of DNA methyltransferase activity in human cancer and identify bortezomib as a novel epigenetic-targeting drug. PMID:18083845

Liu, Shujun; Liu, Zhongfa; Xie, Zhiliang; Pang, Jiuxia; Yu, Jianhua; Lehmann, Esther; Huynh, Lenguyen; Vukosavljevic, Tamara; Takeki, Mitsui; Klisovic, Rebecca B; Baiocchi, Robert A; Blum, William; Porcu, Pierluigi; Garzon, Ramiro; Byrd, John C; Perrotti, Danilo; Caligiuri, Michael A; Chan, Kenneth K; Wu, Lai-Chu; Marcucci, Guido

2007-12-14

132

PTEN downregulates p75NTR expression by decreasing DNA-binding activity of Sp1  

SciTech Connect

p75NTR is expressed throughout the nervous system and its dysregulation is associated with pathological conditions. We have recently demonstrated a signalling cascade initiated by laminin (LN), which upregulates PTEN and downregulates p75NTR. Here we investigate the mechanism by which PTEN modulates p75NTR. Studies using PTEN mutants show that its protein phosphatase activity directly modulates p75NTR protein expression. Nuclear relocalization of PTEN subsequent to LN stimulation suggests transcriptional control of p75NTR expression, which was confirmed following EMSA and ChIP analysis of Sp1 transcription factor binding activity. LN and PTEN independently decrease the DNA-binding ability of PTEN to the p75NTR promoter. Sp1 regulation of p75NTR occurs via dephosphorylation of Sp1, thus reducing p75NTR transcription and protein expression. This mechanism represents a novel regulatory pathway which controls the expression level of a receptor with broad implications not only for the development of the nervous system but also for progression of pathological conditions.

Rankin, Sherri L.; Guy, Clifford S. [Division of Biomedical Sciences - M5352, Memorial University of Newfoundland, Faculty of Medicine, 300 Prince Philip Drive, St. John's, NL, A1B 3V6 (Canada); Mearow, Karen M. [Division of Biomedical Sciences - M5352, Memorial University of Newfoundland, Faculty of Medicine, 300 Prince Philip Drive, St. John's, NL, A1B 3V6 (Canada)], E-mail: kmearow@mun.ca

2009-02-13

133

Human Glycolipid Transfer Protein Gene (GLTP) Expression Is Regulated by Sp1 and Sp3  

PubMed Central

Glycolipid transfer protein (GLTP) accelerates glycolipid intermembrane transfer via a unique lipid transfer/binding fold (GLTP fold) that defines the GLTP superfamily and is the prototype for functional GLTP-like domains in larger proteins, i.e. FAPP2. Human GLTP is encoded by the single-copy GLTP gene on chromosome 12 (12q24.11 locus), but regulation of GLTP gene expression remains completely unexplored. Herein, the ability of glycosphingolipids (and their sphingolipid metabolites) to regulate the transcriptional expression of GLTP via its promoter has been evaluated. Using luciferase and GFP reporters in concert with deletion mutants, the constitutive and basal (225 bp; ?78% G+C) human GLTP promoters have been defined along with adjacent regulatory elements. Despite high G+C content, translational regulation was not evident by the mammalian target of rapamycin pathway. Four GC-boxes were shown to be functional Sp1/Sp3 transcription factor binding sites. Mutation of one GC-box was particularly detrimental to GLTP transcriptional activity. Sp1/Sp3 RNA silencing and mithramycin A treatment significantly inhibited GLTP promoter activity. Among tested sphingolipid analogs of glucosylceramide, sulfatide, ganglioside GM1, ceramide 1-phosphate, sphingosine 1-phosphate, dihydroceramide, sphingosine, only ceramide, a nonglycosylated precursor metabolite unable to bind to GLTP protein, induced GLTP promoter activity and raised transcript levels in vivo. Ceramide treatment partially blocked promoter activity decreases induced by Sp1/Sp3 knockdown. Ceramide treatment also altered the in vivo binding affinity of Sp1 and Sp3 for the GLTP promoter and decreased Sp3 acetylation. This study represents the first characterization of any Gltp gene promoter and links human GLTP expression to sphingolipid homeostasis through ceramide.

Zou, Xianqiong; Gao, Yongguang; Ruvolo, Vivian R.; Gardner, Tawnya L.; Ruvolo, Peter P.; Brown, Rhoderick E.

2011-01-01

134

Yes and Lyn play a role in nuclear translocation of the Epidermal Growth Factor Receptor  

PubMed Central

The epidermal growth factor receptor (EGFR) is a central regulator of tumor progression in human cancers. Cetuximab is an anti-EGFR antibody that has been approved for use in oncology. Previously we investigated mechanisms of resistance to cetuximab using a model derived from the non-small cell lung cancer line NCI-H226. We demonstrated that cetuximab-resistant clones (CtxR) had increased nuclear localization of the EGFR. This process was mediated by Src family kinases (SFK), and nuclear EGFR played a role in resistance to cetuximab. To better understand SFK mediated nuclear translocation of EGFR, we investigated which SFK member(s) controlled this process as well as the EGFR tyrosine residues that are involved. Analyses of mRNA and protein expression indicated up-regulation of the SFK members Yes and Lyn in all CtxR clones. Further, immunoprecipitation analysis revealed that EGFR interacts with Yes and Lyn in CtxR clones, but not in cetuximab-sensitive (CtxS) parental cells. Using RNAi interference, we found that knockdown of either Yes or Lyn led to loss of EGFR translocation to the nucleus. Conversely, overexpression of Yes or Lyn in low nuclear EGFR expressing CtxS parental cells led to increased nuclear EGFR. Chromatin immunoprecipitation (ChIP) assays confirmed nuclear EGFR complexes associated with the promoter of the known EGFR target genes B-Myb and iNOS. Further, all CtxR clones exhibited up-regulation of B-Myb and iNOS at the mRNA and protein levels. siRNAs directed at Yes or Lyn led to decreased binding of EGFR complexes to the B-Myb and iNOS promoters based on ChIP analyses. SFKs have been shown to phosphorylate EGFR on tyrosines 845 and 1101 (Y845 and Y1101) and mutation of Y1101, but not Y845, impaired nuclear entry of the EGFR. Taken together, our findings demonstrate that Yes and Lyn phosphorylate EGFR at Y1101 which influences EGFR nuclear translocation in this model of cetuximab resistance.

Iida, Mari; Brand, Toni M.; Campbell, David A; Li, Chunrong; Wheeler, Deric L.

2012-01-01

135

Aggressive Play: Contributing Factors of Parental Roles on 3-6 YearOld Boys  

Microsoft Academic Search

This study assessed whether there is a correlation between parenting styles (permissive, authoritative, and authoritarian) and the level of aggressive acts and aggressive language in children's play. The participants were 31 parents and their preschool-age boys from a suburban Montessori School in Northwestern New Jersey. A parenting style survey from Active Parenting was used to assess the parent's discipline style.

Maria McCusker; Stacy Van Doren

136

The Alternative Sigma Factor  E Plays an Important Role in Intestinal Survival and Virulence in Vibrio cholerae  

Microsoft Academic Search

The alternative sigma factor (RpoE) is involved in the response to extracytoplasmic stress and plays a role in the virulence of a variety of different bacteria. To assess the role of in Vibrio cholerae pathogenesis, a rpoE mutant was constructed and analyzed using the infant mouse model. The results here show that contributes significantly to the virulence of V. cholerae.

Gabriela Kovacikova; Karen Skorupski

2002-01-01

137

Bortezomib induces DNA hypomethylation and silenced gene transcription by interfering with Sp1\\/NF-B-dependent DNA methyltransferase activity in acute myeloid leukemia  

Microsoft Academic Search

Bortezomib reversibly inhibits 26S protea- somal degradation, interferes with NF- B, and exhibits antitumor activity in hu- man malignancies. Zinc finger protein Sp1 transactivates DNMT1 gene in mice and is functionally regulated through pro- tein abundance, posttranslational modifi- cations (ie, ubiquitination), or interaction with other transcription factors (ie, NF- B). We hypothesize that inhibition of proteasomal degradation and Sp1\\/NF-B- mediated

Shujun Liu; Zhongfa Liu; Zhiliang Xie; Jiuxia Pang; Jianhua Yu; Esther Lehmann; Lenguyen Huynh; Tamara Vukosavljevic; Mitsui Takeki; Rebecca B. Klisovic; Robert A. Baiocchi; William Blum; Pierluigi Porcu; Ramiro Garzon; John C. Byrd; Danilo Perrotti; Michael A. Caligiuri; Kenneth K. Chan; Lai-Chu Wu; Guido Marcucci

2007-01-01

138

Coactivation of Estrogen Receptor ? (ER?)/Sp1 By Vitamin D Receptor Interacting Protein 150 (DRIP150)  

PubMed Central

Vitamin D-receptor interacting protein (DRIP150) coactivates estrogen receptor ? (ER?)-mediated transactivation in breast cancer cell lines transfected with a construct (pERE3) containing three estrogen responsive elements (EREs). In this study, we show that DRIP150 also coactivates ER?/Sp1-mediated transactivation in ZR-75, MCF-7 and MDA-MB-231 breast cancer cells transfected with a construct (pSp13) containing three consensus GC-rich motifs. Studies on coactivation of wild-type and variant ER?/Sp1 by DRIP150 indicates that the DNA-binding domain and helix 12 in the ligand binding domain of ER? are required and the coactivation response is squelched by overexpressing an NR-box peptide that contains two LXXLL motifs from GRIP2. In contrast, coactivation of ER?/Sp1 by wild-type and mutant DRIP150 expression plasmids show that coactivation of ER?/Sp1 by DRIP150 is independent of the NR-boxes. Deletion analysis of DRIP150 demonstrates that coactivation requires an ?-helical NIFSEVRVYN (amino acids 795-804) motif within twenty-three amino acid sequence (789-811) in the central region of DRIP150 and similar results were obtained for coactivation of ER? by DRIP150. Thus, although different domains of ER? are required for hormone-dependent activation of ER? and ER?/Sp1, coactivation of these transcription factors by DRIP150 requires the ?-helical amino acids 795-804. This is the first report of a coactivator that enhances ER?/Sp1-mediated transactivation in breast cancer cells.

Lee, Jeongeun; Safe, Stephen

2007-01-01

139

Research on Children's Play.  

ERIC Educational Resources Information Center

|Reviews current research on play. Notes different theoretical explanations and maintains no adequate general theory of play exists. Covers such areas as: (1) the effects of toys on play, (2) categories of play, (3) the influence of parents and educators on play, (4) mental activity and play, and (5) factors related to play intensity. (JDH)|

van der Kooij, Rimmert; Meyjes, Henriette Posthumus

1986-01-01

140

Viral Vascular Endothelial Growth Factor Plays a Critical Role in Orf Virus Infection  

Microsoft Academic Search

Infection by the parapoxvirus orf virus causes proliferative skin lesions in which extensive capillary prolif- eration and dilation are prominent histological features. This infective phenotype may be linked to a unique virus-encoded factor, a distinctive new member of the vascular endothelial growth factor (VEGF) family of molecules. We constructed a recombinant orf virus in which the VEGF-like gene was disrupted

LOREEN J. SAVORY; STEVEN A. STACKER; STEPHEN B. FLEMING; BRIAN E. NIVEN; ANDREW A. MERCER

2000-01-01

141

Endothelium-Derived Hyperpolarizing Factor(s). Does it Exist and What Role Does it Play in the Regulation of Blood Flow?  

Microsoft Academic Search

\\u000a The endothelium is a source of many substances that play important roles in the short- and long-term regulation of the cardiovascular\\u000a system. In this review we focus on endothelium-derived hyperpolarizing factor, or EDHF. EDHF is often referred to as the “third\\u000a pathway” as, in addition to nitric oxide (NO) and prostacyclin (PGI2) EDHF seems to play an important role as

Chris R. Triggle; Malarvannan Pannirselvam; Todd J. Anderson; Hong Ding

142

Binding of SP1 to the immediate-early protein-responsive element of the human cytomegalovirus DNA polymerase promoter.  

PubMed Central

Human cytomegalovirus (HCMV), a member of the herpesvirus family of DNA viruses, encodes two major immediate-early (IE) transcription factors, IE72 and IE86, that are important for regulated expression of the viral genome. The purpose of this study was to identify the host cellular components required for regulation of the HCMV DNA polymerase promoter (UL54) by HCMV IE proteins. Extensive mutagenesis defined a DNA element located between -54 and -43 relative to the transcription start site that was required for both basal transcriptional activity and transactivation by viral IE proteins. A single copy of the UL54 -54/-43 sequence enhanced the responsiveness of a heterologous minimal promoter to HCMV IE proteins. Fractionation of extracts prepared from uninfected cells led to the isolation of two cellular proteins with apparent molecular masses of 95 and 105 kDa that bound specifically to the UL54 -54/-43 element. Biochemical and immunochemical analyses identified this protein as the transcription factor SP1. Although initial inspection of the UL54 -54/-43 sequence did not predict an SP1 binding site, subsequent analyses indicated that it is indeed a nonconsensus GC box. We propose that SP1 is required to direct basal levels of promoter activity and that SP1-regulated transcription complexes allow the entry of HCMV IE proteins into the transcription cycle.

Luu, P; Flores, O

1997-01-01

143

Transcriptional Protein Sp1 Regulates LEDGF Transcription by Directly Interacting with Its Cis-Elements in GC-Rich Region of TATA-Less Gene Promoter  

PubMed Central

LEDGF/p75 interacts with DNA/protein to regulate gene expression and function. Despite the recognized diversity of function of LEDGF/p75, knowledge of its transregulation is in its infancy. Here we report that LEDGF/p75 gene is TATA-less, contains GC-rich cis elements and is transcriptionally regulated by Sp1 involving small ubiquitin-like modifier (Sumo1). Using different cell lines, we showed that Sp1 overexpression increased the level of LEDGF/p75 protein and mRNA expression in a concentration-dependent fashion. In contrast, RNA interference depletion of intrinsic Sp1 or treatment with artemisinin, a Sp1 inhibitor, reduced expression of LEDGF/p75, suggesting Sp1-mediated regulation of LEDGF/p75. In silico analysis disclosed three evolutionarily conserved, putative Sp1 sites within LEDGF/p75 proximal promoter (?170/+1 nt). DNA-binding and transactivation assays using deletion and point mutation constructs of LEDGF/p75 promoter-CAT revealed that all Sp1 sites (?50/?43, ?109/?102 and ?146/?139) differentially regulate LEDGF/p75. Cotransfection studies with Sp1 in Drosophila cells that were Sp1-deficient, showed increased LEDGF/p75 transcription, while in lens epithelial cells (LECs) promoter activity was inhibited by artemisinin. These events were correlated with levels of endogenous Sp1-dependent LEDGF/p75 expression, and higher resistance to UVB-induced cell death. ChIP and transactivation assays showed that Sumoylation of Sp1 repressed its transcriptional activity as evidenced through its reduced binding to GC-box and reduced ability to activate LEDGF/p75 transcription. As whole, results revealed the importance of Sp1 in regulating expression of LEDGF/p75 gene and add to our knowledge of the factors that control LEDGF/p75 within cellular microenvironments, potentially providing a foundation for LEDGF/p75 expression-based transcription therapy.

Singh, Dhirendra P.; Bhargavan, Biju; Chhunchha, Bhavana; Kubo, Eri; Kumar, Anil; Fatma, Nigar

2012-01-01

144

Fibroblast-secreted hepatocyte growth factor plays a functional role in esophageal squamous cell carcinoma invasion.  

PubMed

Squamous cell cancers comprise the most common type of human epithelial cancers. One subtype, esophageal squamous cell carcinoma (ESCC), is an aggressive cancer with poor prognosis due to late diagnosis and metastasis. Factors derived from the extracellular matrix (ECM) create an environment conducive to tumor growth and invasion. Specialized cancer-associated fibroblasts (CAFs) in the ECM influence tumorigenesis. We have shown previously that the nature and activation state of fibroblasts are critical in modulating the invasive ability of ESCC in an in vivo-like organotypic 3D cell culture, a form of human tissue engineering. Dramatic differences in invasion of transformed esophageal epithelial cells depended on the type of fibroblast in the matrix. We hypothesize that CAFs create an environment primed for growth and invasion through the secretion of factors. We find that fibroblast secretion of hepatocyte growth factor (HGF) fosters the ability of transformed esophageal epithelial cells to invade into the ECM, although other unidentified factors may cooperate with HGF. Genetic modifications of both HGF in fibroblasts and its receptor Met in epithelial cells, along with pharmacologic inhibition of HGF and Met, underscore the importance of this pathway in ESCC invasion and progression. Furthermore, Met activation is increased upon combinatorial overexpression of epidermal growth factor receptor (EGFR) and p53(R175H), two common genetic mutations in ESCC. These results highlight the potential benefit of the therapeutic targeting of HGF/Met signaling in ESCC and potentially other squamous cancers where this pathway is deregulated. PMID:20534479

Grugan, Katharine D; Miller, Charles G; Yao, Yao; Michaylira, Carmen Z; Ohashi, Shinya; Klein-Szanto, Andres J; Diehl, J Alan; Herlyn, Meenhard; Han, May; Nakagawa, Hiroshi; Rustgi, Anil K

2010-06-01

145

Sp1 Expression Is Disrupted in Schizophrenia; A Possible Mechanism for the Abnormal Expression of Mitochondrial Complex I Genes, NDUFV1 and NDUFV2  

PubMed Central

Background The prevailing hypothesis regards schizophrenia as a polygenic disease, in which multiple genes combine with each other and with environmental stimuli to produce the variance of its clinical symptoms. We investigated whether the ubiquitous transcription factor Sp1 is abnormally expressed in schizophrenia, and consequently can affect the expression of genes implicated in this disorder. Methodology/Principal Findings mRNA of Sp1 and of mitochondrial complex I subunits (NDUFV1, NDUFV2) was analyzed in three postmortem brain regions obtained from the Stanley Foundation Brain Collection, and in lymphocytes of schizophrenic patients and controls. Sp1 role in the transcription of these genes was studied as well. Sp1 was abnormally expressed in schizophrenia in both brain and periphery. Its mRNA alteration pattern paralleled that of NDUFV1 and NDUFV2, decreasing in the prefrontal cortex and the striatum, while increasing in the parieto-occipital cortex and in lymphocytes of schizophrenic patients as compared with controls. Moreover, a high and significant correlation between these genes existed in normal subjects, but was distorted in patients. Sp1 role in the regulation of complex I subunits, was demonstrated by the ability of the Sp1/DNA binding inhibitor, mithramycin, to inhibit the transcription of NDUFV1 and NDUFV2, in neuroblastoma cells. In addition, Sp1 activated NDUFV2 promoter by binding to its three GC-boxes. Both activation and binding were inhibited by mithramycin. Conclusions/Significance These findings suggest that abnormality in Sp1, which can be the main activator/repressor or act in combination with additional transcription factors and is subjected to environmental stimuli, can contribute to the polygenic and clinically heterogeneous nature of schizophrenia.

Ben-Shachar, Dorit; Karry, Rachel

2007-01-01

146

TAF1 Histone Acetyltransferase Activity in Sp1 Activation of the Cyclin D1 Promoter  

PubMed Central

A missense mutation within the histone acetyltransferase (HAT) domain of the TATA binding protein-associated factor TAF1 induces ts13 cells to undergo a late G1 arrest and decreases cyclin D1 transcription. We have found that TAF1 mutants (?844-850 and ?848-850, from which amino acids 844 through 850 and 848 through 850 have been deleted, respectively) deficient in HAT activity are unable to complement the ts13 defect in cell proliferation and cyclin D1 transcription. Chromatin immunoprecipitation assays revealed that histone H3 acetylation was reduced at the cyclin D1 promoter but not the c-fos promoter upon inactivation of TAF1 in ts13 cells. The hypoacetylation of H3 at the cyclin D1 promoter was reversed by treatment with trichostatin A (TSA), a histone deacetylase inhibitor, or by expression of TAF1 proteins that retain HAT activity. Transcription of a chimeric promoter containing the Sp1 sites of cyclin D1 and c-fos core remained TAF1 dependent in ts13 cells. Treatment with TSA restored full activity to the cyclin D1-c-fos chimera at 39.5°C. In vivo genomic footprinting experiments indicate that protein-DNA interactions at the Sp1 sites of the cyclin D1 promoter were compromised at 39.5°C in ts13 cells. These data have led us to hypothesize that TAF1-dependent histone acetylation facilitates transcription factor binding to the Sp1 sites, thereby activating cyclin D1 transcription and ultimately G1-to-S-phase progression.

Hilton, Traci L.; Li, Yun; Dunphy, Elizabeth L.; Wang, Edith H.

2005-01-01

147

Sp1/Sp3 and PU.1 differentially regulate beta(5) integrin gene expression in macrophages and osteoblasts.  

PubMed

Murine osteoclast precursors and osteoblasts express the integrin alpha(v)beta(5), the appearance of which on the cell surface is controlled by the beta(5), and not the alpha(v), subunit. Here, we show that a 173-base pair proximal region of the beta(5) promoter mediates beta(5) basal transcription in macrophage (osteoclast precursor)-like and osteoblast-like cells. DNase I footprinting reveal four regions (FP1-FP4) within the 173-base pair region, protected by macrophage nuclear extracts. In contrast, osteoblast nuclear extracts protect only FP1, FP2, and FP3. FP1, FP2, and FP3 bind Sp1 and Sp3 from both macrophage and osteoblast nuclear extracts. FP4 does not bind osteoblast proteins but binds PU.1 from macrophages. Transfection studies show that FP1 and FP2 Sp1/Sp3 sites act as enhancers in both MC3T3-E1 (osteoblast-like) and J774 (macrophage-like) cell lines, whereas the FP3 Sp1/Sp3 site serves as a silencer. Mutation of the FP2 Sp1/Sp3 site totally abolishes promoter activity in J774 cells, with only partial reduction in MC3T3-E1 cells. Finally, we demonstrate that PU.1 acts as a beta(5) silencer in J774 cells but plays no role in MC3T3-E1 cells. Thus, three Sp1/Sp3 sites regulate beta(5) gene expression in macrophages and osteoblast-like cells, with each element exhibiting cell-type and/or activation-suppression specificity. PMID:10722663

Feng, X; Teitelbaum, S L; Quiroz, M E; Cheng, S L; Lai, C F; Avioli, L V; Ross, F P

2000-03-24

148

Serum response factor plays an important role in the mechanically overloaded plantaris muscle of rats  

Microsoft Academic Search

Molecular signaling pathways linking the hypertrophy after mechanical overloading in vivo have not been identified. Using western blot analysis, immunoprecipitation, and immunohistochemistry, we investigated the effect of the mechanical overloading state on RhoA, serum response factor (SRF), and MyoD in the rat plantaris muscle. Adult male rats (10 weeks of age) were used in this experiment. Compensatory enlargement of the

Kunihiro Sakuma; Junji Nishikawa; Ryuta Nakao; Hiroshi Nakano; Mamoru Sano; Masahiro Yasuhara

2003-01-01

149

Sp1 and CREB regulate basal transcription of the human SNF2L gene  

SciTech Connect

Imitation Switch (ISWI) is a member of the SWI2/SNF2 superfamily of ATP-dependent chromatin remodelers, which are involved in multiple nuclear functions, including transcriptional regulation, replication, and chromatin assembly. Mammalian genomes encode two ISWI orthologs, SNF2H and SNF2L. In order to clarify the molecular mechanisms governing the expression of human SNF2L gene, we functionally examined the transcriptional regulation of human SNF2L promoter. Reporter gene assays demonstrated that the minimal SNF2L promoter was located between positions -152 to -86 relative to the transcription start site. In this region we have identified a cAMP-response element (CRE) located at -99 to -92 and a Sp1-binding site at -145 to -135 that play a critical role in regulating basal activity of human SNF2L gene, which were proven by deletion and mutation of specific binding sites, EMSA, and down-regulating Sp1 and CREB via RNAi. This study provides the first insight into the mechanisms that control basal expression of human SNF2L gene.

Xia Yu; Jiang Baichun; Zou Yongxin; Gao Guimin; Shang Linshan; Chen Bingxi; Liu Qiji [Key Laboratory for Experimental Teratology of the Ministry of Education and Institute of Medical Genetics, Shandong University School of Medicine, Jinan, Shandong 250012 (China); Gong Yaoqin [Key Laboratory for Experimental Teratology of the Ministry of Education and Institute of Medical Genetics, Shandong University School of Medicine, Jinan, Shandong 250012 (China)], E-mail: yxg8@sdu.edu.cn

2008-04-04

150

The transcription factor EPAS-1\\/hypoxia-inducible factor 2 plays an important role in vascular remodeling  

Microsoft Academic Search

We have studied the role of the basic helix-loop-helix-PAS transcription factor EPAS-1\\/hypoxia-inducible factor 2 in vascular development by gene targeting. In ICR\\/129 Sv outbred background, more than half of the mutants displayed varying degrees of vascular disorganization, typically in the yolk sac, and died in utero between embryonic day (E)9.5 and E13.5. In mutant embryos directly derived from EPAS-1\\/ embryonic

Jun Peng; Liyong Zhang; Linsay Drysdale; Guo-Hua Fong

2000-01-01

151

The cytotoxic necrotizing factor 1 from E. coli: a janus toxin playing with cancer regulators.  

PubMed

Certain strains of Escherichia coli have been indicated as a risk factor for colon cancer. E. coli is a normal inhabitant of the human intestine that becomes pathogenic, especially in extraintestinal sites, following the acquisition of virulence factors, including the protein toxin CNF1. This Rho GTPases-activating toxin induces dysfunctions in transformed epithelial cells, such as apoptosis counteraction, pro-inflammatory cytokines' release, COX2 expression, NF-kB activation and boosted cellular motility. As cancer may arise when the same regulatory pathways are affected, it is conceivable to hypothesize that CNF1-producing E. coli infections can contribute to cancer development. This review focuses on those aspects of CNF1 related to transformation, with the aim of contributing to the identification of a new possible carcinogenic agent from the microbial world. PMID:23949007

Fabbri, Alessia; Travaglione, Sara; Ballan, Giulia; Loizzo, Stefano; Fiorentini, Carla

2013-08-14

152

Nuclear factor of activated T-cells (NFAT) plays a role in SV40 infection  

SciTech Connect

Recent evidence highlighted a role for the transcription factor, nuclear factor of activated T-cells (NFAT), in the transcription of the human polyomavirus JCV. Here we show that NFAT is also important in the transcriptional control of the related polyomavirus, Simian Virus 40 (SV40). Inhibition of NFAT activity reduced SV40 infection of Vero, 293A, and HeLa cells, and this block occurred at the stage of viral transcription. Both NFAT3 and NFAT4 bound to the SV40 promoter through {kappa}B sites located within the 72 bp repeated enhancer region. In Vero cells, NFAT was involved in late transcription, but in HeLa and 293A cells both early and late viral transcription required NFAT activity. SV40 large T-Ag was found to increase NFAT activity and provided a positive feedback loop to transactivate the SV40 promoter.

Manley, Kate [Graduate Program in Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI 02912 (United States); O'Hara, Bethany A. [Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI 02912 (United States); Atwood, Walter J. [Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI 02912 (United States)], E-mail: Walter_Atwood@Brown.edu

2008-03-01

153

Replication Factor C Complexes Play Unique Pro and Anti-Establishment Roles in Sister Chromatid Cohesion  

Microsoft Academic Search

Recent studies have lead to a rapid expansion of sister chromatid cohesion pathways. Of particular interest is the growth in classifications of anti-establishment factors—now including those that are cohesin-associated (Rad61\\/WAPL and Pds5) or DNA replication fork-associated (Elg1-RFC). In this study, we show that the two classes of anti-establishment complexes are indistinguishable when challenged both genetically and functionally. These findings suggest

Marie E. Maradeo; Robert V. Skibbens; Michael Lichten

2010-01-01

154

Stress incontinence in females: which factors play a role in operative results?  

Microsoft Academic Search

During the years 1981–1985, 251 female patients with stress incontinence consulted the department. The average age was 47.3 years. Surgical treatment consisting of cystourethropexy ad modem Marshall-Marchetti-Krantz, Stamey-Pereyra, or by fascial sling and\\/or periurethral injection with Teflon was performed in 185 patients, with a total of 215 procedures. In a retrospective study, factors which could possibly predict the results of

M. A. Affandi; A. E. J. L. Kramer; U. Jonas

1988-01-01

155

A microfluidic-FCS platform for investigation on the dissociation of Sp1-DNA complex by doxorubicin  

PubMed Central

The transcription factor (TF) Sp1 is a well-known RNA polymerase II transcription activator that binds to GC-rich recognition sites in a number of essential cellular and viral promoters. In addition, direct interference of Sp1 binding to DNA cognate sites using DNA-interacting compounds may provide promising therapies for suppression of cancer progression and viral replication. In this study, we present a rapid, sensitive and cost-effective evaluation of a GC intercalative drug, doxorubicin (DOX), in dissociating the Sp1–DNA complex using fluorescence correlation spectroscopy (FCS) in a microfluidic system. FCS allows assay miniaturization without compromising sensitivity, making it an ideal analytical method for integration of binding assays into high-throughput, microfluidic platforms. A polydimethylsiloxane (PDMS)-based microfluidic chip with a mixing network is used to achieve specific drug concentrations for drug titration experiments. Using FCS measurements, the IC50 of DOX on the dissociation of Sp1–DNA complex is estimated to be 0.55 ?M, which is comparable to that measured by the electrophoretic mobility shift assay (EMSA). However, completion of one drug titration experiment on the proposed microfluidic-FCS platform is accomplished using only picograms of protein and DNA samples and less than 1 h total assay time, demonstrating vast improvements over traditional ensemble techniques.

Yeh, Hsin-Chih; Puleo, Christopher M.; Lim, Teck Chuan; Ho, Yi-Ping; Giza, Paul E.; Huang, Ru Chih C.; Wang, Tza-Huei

2006-01-01

156

PLAYING SAFE, PLAYING DEEP  

Microsoft Academic Search

New product development (NPD) teams must be ambidextrous to be successful - they must be creative in exploring and playing with new knowledge but also capable of exploiting, integrating and applying existing knowledge in order to move efficiently from ideas to reality. And yet, it is not clear how NPD teams can best accomplish this balance. We analyze this problem

Dagmar Hildebrand; Jordi Trullen; Alfons Sauquet

157

Prefoldin Plays a Role as a Clearance Factor in Preventing Proteasome Inhibitor-induced Protein Aggregation.  

PubMed

Prefoldin is a molecular chaperone composed of six subunits, PFD1-6, and prevents misfolding of newly synthesized nascent polypeptides. Although it is predicted that prefoldin, like other chaperones, modulates protein aggregation, the precise function of prefoldin against protein aggregation under physiological conditions has never been elucidated. In this study, we first established an anti-prefoldin monoclonal antibody that recognizes the prefoldin complex but not its subunits. Using this antibody, it was found that prefoldin was localized in the cytoplasm with dots in co-localization with polyubiquitinated proteins and that the number and strength of dots were increased in cells that had been treated with lactacystin, a proteasome inhibitor, and thapsigargin, an inducer of endoplasmic reticulum stress. Knockdown of prefoldin increased the level of SDS-insoluble ubiquitinated protein and reduced cell viability in lactacystin and thapsigargin-treated cells. Opposite results were obtained in prefoldin-overexpressed cells. It has been reported that mice harboring a missense mutation L110R of MM-1?/PFD5 exhibit neurodegeneration in the cerebellum. Although the prefoldin complex containing L110R MM-1? was properly formed in vitro and in cells derived from L110R MM-1? mice, the levels of ubiquitinated proteins and cytotoxicity were higher in L110R MM-1? cells than in wild-type cells under normal conditions and were increased by lactacystin and thapsigargin treatment, and growth of L110R MM-1? cells was attenuated. Furthermore, the polyubiquitinated protein aggregation level was increased in the brains of L110R MM-1? mice. These results suggest that prefoldin plays a role in quality control against protein aggregation and that dysfunction of prefoldin is one of the causes of neurodegenerative diseases. PMID:23946485

Abe, Akira; Takahashi-Niki, Kazuko; Takekoshi, Yuka; Shimizu, Takashi; Kitaura, Hirotake; Maita, Hiroshi; Iguchi-Ariga, Sanae M M; Ariga, Hiroyoshi

2013-08-14

158

Do you want to play? Factors influencing nurse academics' adoption of simulation in their teaching practices.  

PubMed

Simulation based education (SBE) in healthcare is gaining popularity. It provides an opportunity for students to acquire and practice clinical skills in a safe and controlled environment and is also a potential solution to alleviating the increasing pressure on clinical placement availability. While there is growing evidence of the value of simulation to learners there is little understanding of the factors that influence academics attitudes towards and choices about the use simulation. Through an exploratory research design using semi-structured interviews, nurse academics' opinions, experiences and attitudes regarding simulation were captured. Thematic analysis was conducted utilising a cross comparative approach. Three themes Simulation as a Separate Entity; Getting Political, and Academic Adaptation were identified. These themes were then explored through the five essential characteristics of innovation identified in the persuasion phase of Roger's Diffusion of Innovation Model (1995). The findings indicated that in order to successfully integrate simulation into a university curriculum, the factors influencing nurse academics' attitudes and choices around simulation must be understood and addressed to avoid fragmentation of teaching and learning and to support strong learning outcomes. PMID:22133483

Miller, Andrea; Bull, Rosalind M

2011-11-30

159

Mineralocorticoid receptor interaction with SP1 generates a new response element for pathophysiologically relevant gene expression  

PubMed Central

The mineralocorticoid receptor (MR) is a ligand-induced transcription factor belonging to the steroid receptor family and involved in water-electrolyte homeostasis, blood pressure regulation, inflammation and fibrosis in the renocardiovascular system. The MR shares a common hormone-response-element with the glucocorticoid receptor but nevertheless elicits MR-specific effects including enhanced epidermal growth factor receptor (EGFR) expression via unknown mechanisms. The EGFR is a receptor tyrosine kinase that leads to activation of MAP kinases, but that can also function as a signal transducer for other signaling pathways. In the present study, we mechanistically investigate the interaction between a newly discovered MR- but not glucocorticoid receptor- responsive-element (=MRE1) of the EGFR promoter, specificity protein 1 (SP1) and MR to gain general insights into MR-specificity. Biological relevance of the interaction for EGFR expression and consequently for different signaling pathways in general is demonstrated in human, rat and murine vascular smooth muscle cells and cells of EGFR knockout mice. A genome-wide promoter search for identical binding regions followed by quantitative PCR validation suggests that the identified MR-SP1–MRE1 interaction might be applicable to other genes. Overall, a novel principle of MR-specific gene expression is explored that applies to the pathophysiologically relevant expression of the EGFR and potentially also to other genes.

Meinel, Sandra; Ruhs, Stefanie; Schumann, Katja; Stratz, Nicole; Trenkmann, Kay; Schreier, Barbara; Grosse, Ivo; Keilwagen, Jens; Gekle, Michael; Grossmann, Claudia

2013-01-01

160

Mineralocorticoid receptor interaction with SP1 generates a new response element for pathophysiologically relevant gene expression.  

PubMed

The mineralocorticoid receptor (MR) is a ligand-induced transcription factor belonging to the steroid receptor family and involved in water-electrolyte homeostasis, blood pressure regulation, inflammation and fibrosis in the renocardiovascular system. The MR shares a common hormone-response-element with the glucocorticoid receptor but nevertheless elicits MR-specific effects including enhanced epidermal growth factor receptor (EGFR) expression via unknown mechanisms. The EGFR is a receptor tyrosine kinase that leads to activation of MAP kinases, but that can also function as a signal transducer for other signaling pathways. In the present study, we mechanistically investigate the interaction between a newly discovered MR- but not glucocorticoid receptor- responsive-element (=MRE1) of the EGFR promoter, specificity protein 1 (SP1) and MR to gain general insights into MR-specificity. Biological relevance of the interaction for EGFR expression and consequently for different signaling pathways in general is demonstrated in human, rat and murine vascular smooth muscle cells and cells of EGFR knockout mice. A genome-wide promoter search for identical binding regions followed by quantitative PCR validation suggests that the identified MR-SP1-MRE1 interaction might be applicable to other genes. Overall, a novel principle of MR-specific gene expression is explored that applies to the pathophysiologically relevant expression of the EGFR and potentially also to other genes. PMID:23821666

Meinel, Sandra; Ruhs, Stefanie; Schumann, Katja; Strätz, Nicole; Trenkmann, Kay; Schreier, Barbara; Grosse, Ivo; Keilwagen, Jens; Gekle, Michael; Grossmann, Claudia

2013-07-01

161

The Prrx1 homeodomain transcription factor plays a central role in pancreatic regeneration and carcinogenesis  

PubMed Central

Pancreatic exocrine cell plasticity can be observed during development, pancreatitis with subsequent regeneration, and also transformation. For example, acinar–ductal metaplasia (ADM) occurs during acute pancreatitis and might be viewed as a prelude to pancreatic intraepithelial neoplasia (PanIN) and pancreatic ductal adenocarcinoma (PDAC) development. To elucidate regulatory processes that overlap ductal development, ADM, and the progression of normal cells to PanIN lesions, we undertook a systematic approach to identify the Prrx1 paired homeodomain Prrx1 transcriptional factor as a highly regulated gene in these processes. Prrx1 annotates a subset of pancreatic ductal epithelial cells in Prrx1creERT2-IRES-GFP mice. Furthermore, sorted Prrx1+ cells have the capacity to self-renew and expand during chronic pancreatitis. The two isoforms, Prrx1a and Prrx1b, regulate migration and invasion, respectively, in pancreatic cancer cells. In addition, Prrx1b is enriched in circulating pancreatic cells (Pdx1cre;LSL-KrasG12D/+;p53fl/+;R26YFP). Intriguingly, the Prrx1b isoform, which is also induced in ADM, binds the Sox9 promoter and positively regulates Sox9 expression. This suggests a new hierarchical scheme whereby a Prrx1–Sox9 axis may influence the emergence of acinar–ductal metaplasia and regeneration. Furthermore, our data provide a possible explanation of why pancreatic cancer is skewed toward a ductal fate.

Reichert, Maximilian; Takano, Shigetsugu; von Burstin, Johannes; Kim, Sang-Bae; Lee, Ju-Seog; Ihida-Stansbury, Kaori; Hahn, Christopher; Heeg, Steffen; Schneider, Gunter; Rhim, Andrew D.; Stanger, Ben Z.; Rustgi, Anil K.

2013-01-01

162

Replication Factor C Complexes Play Unique Pro- and Anti-Establishment Roles in Sister Chromatid Cohesion  

PubMed Central

Recent studies have lead to a rapid expansion of sister chromatid cohesion pathways. Of particular interest is the growth in classifications of anti-establishment factors—now including those that are cohesin-associated (Rad61/WAPL and Pds5) or DNA replication fork-associated (Elg1-RFC). In this study, we show that the two classes of anti-establishment complexes are indistinguishable when challenged both genetically and functionally. These findings suggest that both classes function in a singular pathway that is centered on Ctf7/Eco1 (herein termed Ctf7) regulation. The anti-establishment activity of Elg1-RFC complex is particular intriguing given that an alternate Ctf18-RFC complex exhibits robust pro-establishment activity. Here, we provide several lines of evidence, including the use of Ctf7 bypass suppressors, indicating that these activities are not simply antagonistic. Moreover, the results suggest that Ctf18-RFC is capable of promoting sister chromatid pairing reactions independent of Ctf7. The combination of these studies suggest a new model of sister chromatid pairing regulation.

Maradeo, Marie E.; Skibbens, Robert V.

2010-01-01

163

Yes and Lyn play a role in nuclear translocation of the epidermal growth factor receptor.  

PubMed

The epidermal growth factor receptor (EGFR) is a central regulator of tumor progression in human cancers. Cetuximab is an anti-EGFR antibody that has been approved for use in oncology. Previously we investigated mechanisms of resistance to cetuximab using a model derived from the non-small cell lung cancer line NCI-H226. We demonstrated that cetuximab-resistant clones (Ctx(R)) had increased nuclear localization of the EGFR. This process was mediated by Src family kinases (SFKs), and nuclear EGFR had a role in resistance to cetuximab. To better understand SFK-mediated nuclear translocation of EGFR, we investigated which SFK member(s) controlled this process as well as the EGFR tyrosine residues that are involved. Analyses of mRNA and protein expression indicated upregulation of the SFK members Yes (v-Yes-1 yamaguchi sarcoma viral oncogene) and Lyn (v-yes-1 Yamaguchi sarcoma viral-related oncogene homolog) in all Ctx(R) clones. Further, immunoprecipitation analysis revealed that EGFR interacts with Yes and Lyn in Ctx(R) clones, but not in cetuximab-sensitive (Ctx(S)) parental cells. Using RNAi interference, we found that knockdown of either Yes or Lyn led to loss of EGFR translocation to the nucleus. Conversely, overexpression of Yes or Lyn in low nuclear EGFR-expressing Ctx(S) parental cells led to increased nuclear EGFR. Chromatin immunoprecipitation (ChIP) assays confirmed nuclear EGFR complexes associated with the promoter of the known EGFR target genes B-Myb and iNOS. Further, all Ctx(R) clones exhibited upregulation of B-Myb and iNOS at the mRNA and protein levels. siRNAs directed at Yes or Lyn led to decreased binding of EGFR complexes to the B-Myb and iNOS promoters based on ChIP analyses. SFKs have been shown to phosphorylate EGFR on tyrosines 845 and 1101 (Y845 and Y1101), and mutation of Y1101, but not Y845, impaired nuclear entry of the EGFR. Taken together, our findings demonstrate that Yes and Lyn phosphorylate EGFR at Y1101, which influences EGFR nuclear translocation in this model of cetuximab resistance. PMID:22430206

Iida, M; Brand, T M; Campbell, D A; Li, C; Wheeler, D L

2012-03-19

164

PTEN/MAPK pathways play a key role in platelet-activating factor-induced experimental pulmonary tumor metastasis.  

PubMed

In this study, we investigated the role of PTEN (phosphatase and tensin homolog deleted on chromosome 10) in a platelet-activating factor (PAF)-induced experimental pulmonary tumor metastasis model. An adenovirus carrying PTEN cDNA (Ad-PTEN) reversed PAF-induced increase in phosphorylation of AKT as well as pulmonary metastasis of B16F10. PAF-induced pulmonary metastasis was inhibited by MAPK inhibitors, but not by PI3K inhibitor. Ad-PTEN abrogated PAF-induced phosphorylation of MAPKs. These data indicate PTEN/MAPK pathways play a key role in PAF-induced tumor metastasis. PMID:23137704

Kim, Han-A; Kim, Kyoung-Jin; Seo, Kook Heon; Lee, Hern-Ku; Im, Suhn-Young

2012-11-05

165

Sp1 and C\\/EBP are necessary to activate the lactoferrin gene promoter during myeloid differentiation  

Microsoft Academic Search

In this study, we sought to identify factors responsible for the positive modulation of lactoferrin (LF), a neutrophil-specific, secondary-granule protein gene. Initial reporter gene transfection assays indi- cated that the first 89 base pairs of the LF promoter are capable of directing myeloid- specific LF gene expression. The pres- ence of a C\\/EBP site flanked by 2 Sp1 sites within

Arati Khanna-Gupta; Theresa Zibello; Carl Simkevich; Alan G. Rosmarin; Nancy Berliner

166

TAK1 plays a major role in growth factor-induced phenotypic modulation of airway smooth muscle.  

PubMed

Increased airway smooth muscle (ASM) mass is a major feature of airway remodeling in asthma and chronic obstructive pulmonary disease. Growth factors induce a proliferative ASM phenotype, characterized by an increased proliferative state and a decreased contractile protein expression, reducing contractility of the muscle. Transforming growth factor-?-activated kinase 1 (TAK1), a mitogen-activated protein kinase kinase kinase, is a key enzyme in proinflammatory signaling in various cell types; however, its function in ASM is unknown. The aim of this study was to investigate the role of TAK1 in growth factor-induced phenotypic modulation of ASM. Using bovine tracheal smooth muscle (BTSM) strips and cells, as well as human tracheal smooth muscle cells, we investigated the role of TAK1 in growth factor-induced proliferation and hypocontractility. Platelet-derived growth factor- (PDGF; 10 ng/ml) and fetal bovine serum (5%)-induced increases in DNA synthesis and cell number in bovine and human cells were significantly inhibited by pretreatment with the specific TAK1 inhibitor LL-Z-1640-2 (5Z-7-oxozeaenol; 100 nM). PDGF-induced DNA synthesis and extracellular signal-regulated kinase-1/2 phosphorylation in BTSM cells were strongly inhibited by both LL-Z-1640-2 pretreatment and transfection of dominant-negative TAK1. In addition, LL-Z-1640-2 inhibited PDGF-induced reduction of BTSM contractility and smooth muscle ?-actin expression. The data indicate that TAK1 plays a major role in growth factor-induced phenotypic modulation of ASM. PMID:21873447

Pera, Tonio; Sami, Riham; Zaagsma, Johan; Meurs, Herman

2011-08-26

167

A formal anthropological view of motivation models of problematic MMO play: achievement, social, and immersion factors in the context of culture.  

PubMed

Yee (2006) found three motivational factors-achievement, social, and immersion-underlying play in massively multiplayer online role-playing games ("MMORPGs" or "MMOs" for short). Subsequent work has suggested that these factors foster problematic or addictive forms of play in online worlds. In the current study, we used an online survey of respondents (N?=?252), constructed and also interpreted in reference to ethnography and interviews, to examine problematic play in the World of Warcraft (WoW; Blizzard Entertainment, 2004-2013). We relied on tools from psychological anthropology to reconceptualize each of Yee's three motivational factors in order to test for the possible role of culture in problematic MMO play: (a) For achievement, we examined how "cultural consonance" with normative understandings of success might structure problematic forms of play; (b) for social, we analyzed the possibility that developing overvalued virtual relationships that are cutoff from offline social interactions might further exacerbate problematic play; and (c) in relation to immersion, we examined how "dissociative" blurring of actual- and virtual-world identities and experiences might contribute to problematic patterns. Our results confirmed that compared to Yee's original motivational factors, these culturally sensitive measures better predict problematic forms of play, pointing to the important role of sociocultural factors in structuring online play. PMID:23690445

Snodgrass, Jeffrey G; Dengah, H J Francois; Lacy, Michael G; Fagan, Jesse

2013-05-20

168

New Play.  

ERIC Educational Resources Information Center

|There have been many theories and hypotheses about play, one of which is the equation of play with "transcendence." Play may have the ingredients to allow us to transcend and, for a moment, remythologize life. There have been recent authors who have given play the status of theology, indicating that play contains elements also found in religion.…

Lersten, Kenneth C.

169

Inhibition of Sp1 dependent transcription and antitumor activity of the new aureolic acid analogues Mithramycin SDK and SK in human ovarian cancer xenografts  

PubMed Central

Objective Increased activity of Sp family of transcription factors is a frequent and critical event in cancer development and progression. Genes governing tumor growth, invasion and angiogenesis are regulated by Sp factors, like Sp1, Sp3 or Sp4, and are frequently over-expressed in tumors. Targeting Sp factors has been explored as a therapeutic approach. Mithramycin (MTM) is a natural antibiotic that binds DNA and inhibit Sp1-dependent transcription. New analogues, named MTM-SDK and MTM-SK, were recently obtained by genetic engineering of the MTM biosynthetic pathway and have demonstrated improved transcriptional and antiproliferative activity in ovarian cancer cell lines in vitro. In present study we evaluated the activity of the new compounds in human ovarian cancer xenografts. Methods Expression of Sp1 and target proteins in ovarian cancer specimens and tumor xenografts was assessed by immunohistochemistry. Drug –induced silencing of Sp1-regulated genes in cells and tumor xenograft samples was assessed by quantitative RT-PCR. Toxicity and antitumor activity of the compounds were investigated in healthy and tumor-bearing immunocompromised mice, respectively. Results Expression of Sp1 was frequently increased in human epithelial ovarian cancers. MTM-SDK and MTM-SK acted as potent inhibitors of Sp1-dependent transcription both in vitro and in tumor xenografts. Both compounds were well tolerated even after prolonged administration and delayed growth of ovarian tumor xenografts. MTM-SDK was particularly effective against orthotopic tumors leading to a significant increase of survival and delay of tumor progression. Conclusions MTM-SDK and MTM-SK show relevant activity in vivo and represent interesting candidates for treatment of ovarian cancers.

Previdi, Sara; Malek, Anastasia; Albertini, Veronica; Riva, Cristina; Capella, Carlo; Broggini, Massimo; Carbone, Giuseppina M.; Rohr, Jurgen; Catapano, Carlo V.

2010-01-01

170

Arabidopsis Transcription Factor ELONGATED HYPOCOTYL5 Plays a Role in the Feedback Regulation of Phytochrome A Signaling[C][W  

PubMed Central

Phytochrome A (phyA) is the primary photoreceptor responsible for perceiving and mediating various responses to far-red light in Arabidopsis thaliana. FAR-RED ELONGATED HYPOCOTYL1 (FHY1) and its homolog FHY1-LIKE (FHL) are two small plant-specific proteins essential for light-regulated phyA nuclear accumulation and subsequent phyA signaling processes. FHY3 and its homolog FAR-RED IMPAIRED RESPONSE1 (FAR1) are two transposase-derived transcription factors that directly activate FHY1/FHL transcription and thus mediate subsequent phyA nuclear accumulation and responses. Here, we report that ELONGATED HYPOCOTYL5 (HY5), a well-characterized bZIP transcription factor involved in promoting photomorphogenesis, directly binds ACGT-containing elements a few base pairs away from the FHY3/FAR1 binding sites in the FHY1/FHL promoters. We demonstrate that HY5 physically interacts with FHY3/FAR1 through their respective DNA binding domains and negatively regulates FHY3/FAR1-activated FHY1/FHL expression under far-red light. Together, our data show that HY5 plays a role in negative feedback regulation of phyA signaling by attenuating FHY3/FAR1-activated FHY1/FHL expression, providing a mechanism for fine-tuning phyA signaling homeostasis.

Li, Jigang; Li, Gang; Gao, Shumin; Martinez, Cristina; He, Guangming; Zhou, Zhenzhen; Huang, Xi; Lee, Jae-Hoon; Zhang, Huiyong; Shen, Yunping; Wang, Haiyang; Deng, Xing Wang

2010-01-01

171

Macrophage migration inhibitory factor plays a critical role in mediating protection against the helminth parasite Taenia crassiceps.  

PubMed

To determine the role of endogenous migration inhibitory factor (MIF) in regulation of immune response during murine cysticercosis caused by the helminth parasite Taenia crassiceps, we analyzed the course of T. crassiceps infection in MIF(-/-) BALB/c mice. MIF(-/-) mice were highly susceptible to T. crassiceps and developed significantly higher parasite loads compared to similarly infected MIF(+/+) mice. Throughout the course of infection, Taenia crassiceps soluble antigen-stimulated spleen cells from both MIF(+/+) and MIF(-/-) mice produced significant and comparable levels of interleukin-4 (IL-4), but those from MIF(-/-) mice produced significantly more IL-13, as well as gamma interferon (IFN-gamma), suggesting that the susceptibility of MIF(-/-) mice to T. crassiceps was not due to the lack of IFN-gamma production. Interestingly, low levels of both total and specific immunoglobulin G2a were observed in MIF(-/-) cysticercotic mice despite the high IFN-gamma levels; in addition, peritoneal macrophages obtained from T. crassiceps-infected MIF(-/-) mice at different time points failed to respond efficiently to stimulation in vitro with lipopolysaccharide plus IFN-gamma and produced significantly lower levels of IL-12, tumor necrosis factor alpha, and NO compared to those from MIF(+/+) mice. These findings demonstrate that MIF plays a critical role in mediating protection against T. crassiceps in vivo. Moreover, these findings also suggest that impaired macrophage function rather than the lack of Th1 development may be responsible for mediating susceptibility to T. crassiceps. PMID:12595439

Rodríguez-Sosa, Miriam; Rosas, Lucia E; David, John R; Bojalil, Rafael; Satoskar, Abhay R; Terrazas, Luis I

2003-03-01

172

Play: Children's Business and a Guide to Play Materials.  

ERIC Educational Resources Information Center

|This collection of articles presents ideas about the value of children's play and suggests practical ways to implement good play experiences and select appropriate play materials. Articles examine play as an agent of social values, play and thinking, play and child development, the environmental opportunities for play factors that can destroy the…

Markun, Patricia Maloney, Ed.

173

Sp1 and Sp3 regulate transcription of the cyclin-dependent kinase 5 regulatory subunit 2 (p39) promoter in neuronal cells  

PubMed Central

Cyclin dependent kinase 5 (cdk5) activity is critical for development and function of the nervous system. Cdk5 activity is dependent on association with the regulators p35 and p39 whose expression is highly regulated in the developing nervous system. We have identified a small 200bp fragment of the p39 promoter that is sufficient for cell type-specific expression in neuronal cells. Mutational analysis revealed that a cluster of predicted binding sites for Sp1, AP-1/CREB/ATF and E box-binding transcription factors is essential for full activity of the p39 promoter. Electrophoretic mobility shift assays revealed that Sp1 and Sp3 bound to sequences required for p39 promoter function and chromatin immunoprecipitation assays confirmed binding of these proteins to the endogenous p39 promoter. Furthermore, depletion of either Sp1 or Sp3 by siRNA reduced expression from the p39 promoter. Our data suggest that the ubiquitously expressed transcription factors Sp1 and Sp3 regulate transcription of the cdk5 regulator p39 in neuronal cells, possibly in cooperation with tissue-specific transcription factors.

Valin, Alvaro; Cook, Julie D.; Ross, Sarah; Saklad, Christi L.; Gill, Grace

2009-01-01

174

Sp1/Sp3 and DNA-methylation contribute to basal transcriptional activation of human podoplanin in MG63 versus Saos-2 osteoblastic cells  

PubMed Central

Background Podoplanin is a membrane mucin that, among a series of tissues, is expressed on late osteoblasts and osteocytes. Since recent findings have focussed on podoplanin's potential role as a tumour progression factor, we aimed at identifying regulatory elements conferring PDPN promoter activity. Here, we characterized the molecular mechanism controlling basal PDPN transcription in human osteoblast-like MG63 versus Saos-2 cells. Results We cloned and sequenced 2056 nucleotides from the 5'-flanking region of the PDPN gene and a computational search revealed that the TATA and CAAT box-lacking promoter possesses features of a growth-related gene, such as a GC-rich 5' region and the presence of multiple putative Sp1, AP-4 and NF-1 sites. Reporter gene assays demonstrated a functional promoter in MG63 cells exhibiting 30-fold more activity than in Saos-2 cells. In vitro DNase I footprinting revealed eight protected regions flanked by DNaseI hypersensitive sites within the region bp -728 to -39 present in MG63, but not in Saos-2 cells. Among these regions, mutation and supershift electrophoretic mobility shift assays (EMSA) identified four Sp1/Sp3 binding sites and two binding sites for yet unknown transcription factors. Deletion studies demonstrated the functional importance of two Sp1/Sp3 sites for PDPN promoter activity. Overexpression of Sp1 and Sp3 independently increased the stimulatory effect of the promoter and podoplanin mRNA levels in MG63 and Saos-2 cells. In SL2 cells, Sp3 functioned as a repressor, while Sp1 and Sp3 acted positively synergistic. Weak PDPN promoter activity of Saos-2 cells correlated with low Sp1/Sp3 nuclear levels, which was confirmed by Sp1/Sp3 chromatin immunoprecipitations in vivo. Moreover, methylation-sensitive Southern blot analyses and bisulfite sequencing detected strong methylation of CpG sites upstream of bp -464 in MG63 cells, but hypomethylation of these sites in Saos-2 cells. Concomitantly, treatment with the DNA methyltransferase inhibitor 5-azaCdR in combination with trichostatin A (TSA) downregulated podoplanin mRNA levels in MG63 cells, and region-specific in vitro methylation of the distal promoter suggested that DNA methylation rather enhanced than hindered PDPN transcription in both cell types. Conclusion These data establish that in human osteoblast-like MG63 cells, Sp1 and Sp3 stimulate basal PDPN transcription in a concerted, yet independent manner, whereas Saos-2 cells lack sufficient nuclear Sp protein amounts for transcriptional activation. Moreover, a highly methylated chromatin conformation of the distal promoter region confers cell-type specific podoplanin upregulation versus Saos-2 cells.

Hantusch, Brigitte; Kalt, Romana; Krieger, Sigurd; Puri, Christina; Kerjaschki, Dontscho

2007-01-01

175

Adjacent proline residues in the inhibitory domain of the Oct-2 transcription factor play distinct functional roles.  

PubMed Central

A 40 amino acid region of Oct-2 from amino acids 142 to 181 functions as an active repressor domain capable of inhibiting both basal activity and activation of promoters containing a TATA box, but not of those that contain an initiator element. Based on our observation that the equivalent region of the closely related Oct-1 factor does not act as an inhibitory domain, we have mutated specific residues in the Oct-2 domain in an attempt to probe their importance in repressor domain function. Although mutations of several residues have no or minimal effect, mutation of proline 175 to arginine abolishes the ability to inhibit both basal and activated transcription. In contrast, mutation of proline 174 to arginine confers upon the domain the ability to repress activation of an initiator-containing promoter by acidic activation domains, and also suppresses the effect of the proline 175 mutation. Hence, adjacent proline residues play key roles in the functioning of the inhibitory domain and in limiting its specificity to TATA-box-containing promoters.

Liu, Y Z; Lee, I K; Locke, I; Dawson, S J; Latchman, D S

1998-01-01

176

Fibroblast Growth Factor 22 Is Not Essential for Skin Development and Repair but Plays a Role in Tumorigenesis  

PubMed Central

Fibroblast Growth Factors play critical roles during development, tissue homeostasis and repair by controlling cell proliferation, survival, migration and differentiation. Of the 22 mammalian FGFs, FGF22, a member of the FGF7/10/22 subfamily, has been shown to have a clear role in synaptogenesis, but its roles in other tissues have not been studied. We have investigated the in vivo functions of FGF22 in mice. Fgf22 null animals were viable, fertile and did not display any obvious abnormalities. Despite the known expression profile of FGF22 in the skin, no differences in either skin or pelage were observed, demonstrating that FGF22 is dispensable during embryogenesis and in unchallenged adult skin. Mice lacking FGF22 were able to heal acute wounds just as efficiently as wild type mice. However, classical two-step skin carcinogenesis challenge revealed that FGF22 null mice developed fewer papillomas than wild type controls, suggesting a potential pro-oncogenic role for FGF22 in the skin.

Jarosz, Monika; Robbez-Masson, Luisa; Chioni, Athina-Myrto; Cross, Barbara; Rosewell, Ian; Grose, Richard

2012-01-01

177

Play Therapy  

PubMed Central

Play therapy represents a unique form of treatment that is not only geared toward young children, but is translated into a language children can comprehend and utilize—the language of play. For the referring provider or practitioner, questions may remain regarding the nature, course, and efficacy of play therapy. This article reviews the theoretical underpinnings of play therapy, some practical considerations, and finally a summary of the current state of research in regard to play therapy. The authors present the practicing psychiatrist with a road map for referring a patient to play therapy or initiating it in appropriate cases.

Kool, Ritesh

2010-01-01

178

Hesperidin Induces Apoptosis by Inhibiting Sp1 and Its Regulatory Protein in MSTO-211H Cells  

PubMed Central

Hesperidin, a flavanone present in citrus fruits, has been studied as potential therapeutic agents that have anti-tumor activity and apoptotic effects in several cancers, but there is no report about the apoptotic effect of hesperidin in human malignant pleural mesothelioma through the specificity protein 1 (Sp1) protein. We investigated whether hesperidin inhibited cell growth and regulated Sp1 target proteins by suppressing the levels of Sp1 protein in MSTO-211H cells. The IC50 value of hesperidin was determined to be 152.3 ?M in MSTO-211H cells for 48 h. Our results suggested that hesperidin (0-160 ?M) decreased cell viability, and induced apoptotic cell death. Hesperidin increased Sub-G1 population in MSTO-211H cells. Hesperidin significantly suppressed mRNA/protein level of Sp1 and modulated the expression level of the Sp1 regulatory protein such as p27, p21, cyclin D1, Mcl-1, and survivin in mesothelioma cells. Also, hesperidin induced apoptotic signaling including: cleavages of Bid, caspase-3, and PARP, upregulation of Bax, and down-regulation of Bcl-xl in mesothelioma cells. These results show that hesperidin suppressed mesothelioma cell growth through inhibition of Sp1. In this study, we demonstrated that Sp1 acts as a novel molecular target of hesperidin in human malignant pleural mesothelioma.

Lee, Kyung-Ae; Lee, Sang-Han; Lee, Yong-Jin; Baeg, Seung Mi; Shim, Jung-Hyun

2012-01-01

179

On the Role of the SP1 Domain in HIV-1 Particle Assembly: a Molecular Switch??  

PubMed Central

Expression of a retroviral protein, Gag, in mammalian cells is sufficient for assembly of immature virus-like particles (VLPs). VLP assembly is mediated largely by interactions between the capsid (CA) domains of Gag molecules but is facilitated by binding of the nucleocapsid (NC) domain to nucleic acid. We have investigated the role of SP1, a spacer between CA and NC in HIV-1 Gag, in VLP assembly. Mutational analysis showed that even subtle changes in the first 4 residues of SP1 destroy the ability of Gag to assemble correctly, frequently leading to formation of tubes or other misassembled structures rather than proper VLPs. We also studied the conformation of the CA-SP1 junction region in solution, using both molecular dynamics simulations and circular dichroism. Consonant with nuclear magnetic resonance (NMR) studies from other laboratories, we found that SP1 is nearly unstructured in aqueous solution but undergoes a concerted change to an ?-helical conformation when the polarity of the environment is reduced by addition of dimethyl sulfoxide (DMSO), trifluoroethanol, or ethanol. Remarkably, such a coil-to-helix transition is also recapitulated in an aqueous medium at high peptide concentrations. The exquisite sensitivity of SP1 to mutational changes and its ability to undergo a concentration-dependent structural transition raise the possibility that SP1 could act as a molecular switch to prime HIV-1 Gag for VLP assembly. We suggest that changes in the local environment of SP1 when Gag oligomerizes on nucleic acid might trigger this switch.

Datta, Siddhartha A. K.; Temeselew, Lakew G.; Crist, Rachael M.; Soheilian, Ferri; Kamata, Anne; Mirro, Jane; Harvin, Demetria; Nagashima, Kunio; Cachau, Raul E.; Rein, Alan

2011-01-01

180

Transcriptional interference perturbs the binding of Sp1 to the HIV-1 promoter.  

PubMed Central

Transcriptional interference between adjacent genes has been demonstrated in a variety of biological systems. To study this process in RNA polymerase II (pol II) transcribed genes we have analysed the effect of transcription on tandem HIV-1 promoters integrated into the genome of HeLa cells. We show that transcriptional activation at the upstream promoter reduces transcription from the downstream promoter, as compared with basal transcription conditions (in the absence of an activator). Furthermore, insertion of a strong transcriptional termination element between the two promoters alleviates this transcriptional interference, resulting in elevated levels of transcription from the downstream promoter. Actual protein interactions with the downstream (occluded) promoter were analysed by in vivo footprinting. Binding of Sp1 transcription factors to the occluded promoter was reduced, when compared with the footprint pattern of the promoter protected by the terminator. This suggests that promoter occlusion is due to disruption of certain transcription factors and that it can be blocked by an intervening transcriptional terminator. Chromatin mapping with DNase I indicates that a factor binds to the termination element under both basal and induced conditions.

Greger, I H; Demarchi, F; Giacca, M; Proudfoot, N J

1998-01-01

181

Wanna Play?  

ERIC Educational Resources Information Center

In this article, the author talks about the importance of play in the lives of children and describes how games and imaginative play contribute to the development of children. From her decades-old collection of countless incidents demonstrating children's love for self-directed, informal, imaginative play, the author shares three incidents that…

Chenfeld, Mimi Brodsky

2006-01-01

182

Playful Interaction  

Microsoft Academic Search

The video Playful Interaction describes a future architectural office, and envisions ideas and concepts for playful interactions between people, materials and appliances in a pervasive and aug- mented working environment. The video both describes existing developments, technologies and de- signs as well as ideas not yet implemented such as playful modes of interaction with an augmented ball.

METTE AGGER ERIKSEN; PETER GALL KROGH; MARTIN LUDVIGSEN

183

Wanna Play?  

ERIC Educational Resources Information Center

|In this article, the author talks about the importance of play in the lives of children and describes how games and imaginative play contribute to the development of children. From her decades-old collection of countless incidents demonstrating children's love for self-directed, informal, imaginative play, the author shares three incidents that…

Chenfeld, Mimi Brodsky

2006-01-01

184

Platelet-Activating Factor Receptor Plays a Role in Lung Injury and Death Caused by Influenza A in Mice  

PubMed Central

Influenza A virus causes annual epidemics which affect millions of people worldwide. A recent Influenza pandemic brought new awareness over the health impact of the disease. It is thought that a severe inflammatory response against the virus contributes to disease severity and death. Therefore, modulating the effects of inflammatory mediators may represent a new therapy against Influenza infection. Platelet activating factor (PAF) receptor (PAFR) deficient mice were used to evaluate the role of the gene in a model of experimental infection with Influenza A/WSN/33 H1N1 or a reassortant Influenza A H3N1 subtype. The following parameters were evaluated: lethality, cell recruitment to the airways, lung pathology, viral titers and cytokine levels in lungs. The PAFR antagonist PCA4248 was also used after the onset of flu symptoms. Absence or antagonism of PAFR caused significant protection against flu-associated lethality and lung injury. Protection was correlated with decreased neutrophil recruitment, lung edema, vascular permeability and injury. There was no increase of viral load and greater recruitment of NK1.1+ cells. Antibody responses were similar in WT and PAFR-deficient mice and animals were protected from re-infection. Influenza infection induces the enzyme that synthesizes PAF, lyso-PAF acetyltransferase, an effect linked to activation of TLR7/8. Therefore, it is suggested that PAFR is a disease-associated gene and plays an important role in driving neutrophil influx and lung damage after infection of mice with two subtypes of Influenza A. Further studies should investigate whether targeting PAFR may be useful to reduce lung pathology associated with Influenza A virus infection in humans.

Garcia, Cristiana C.; Russo, Remo C.; Guabiraba, Rodrigo; Fagundes, Caio T.; Polidoro, Rafael B.; Tavares, Luciana P.; Salgado, Ana Paula C.; Cassali, Geovanni D.; Sousa, Lirlandia P.; Machado, Alexandre V.; Teixeira, Mauro M.

2010-01-01

185

Play Therapy  

PubMed Central

Play therapy is a treatment modality in which the therapist engages in play with the child. Its use has been documented in a variety of settings and with a variety of diagnoses. Treating within the context of play brings the therapist and the therapy to the level of the child. By way of an introduction to this approach, a case is presented of a six-year-old boy with oppositional defiant disorder. The presentation focuses on the events and interactions of a typical session with an established patient. The primary issues of the session are aggression, self worth, and self efficacy. These themes manifest themselves through the content of the child’s play and narration of his actions. The therapist then reflects these back to the child while gently encouraging the child toward more positive play. Though the example is one of nondirective play therapy, a wide range of variation exists under the heading of play therapy.

Lawver, Timothy; Blankenship, Kelly

2008-01-01

186

Matriptase\\/MT-SP1 is required for postnatal survival, epidermal barrier function, hair follicle development, and thymic homeostasis  

Microsoft Academic Search

Matriptase\\/MT-SP1 is a novel tumor-associated type II transmembrane serine protease that is highly expressed in the epidermis, thymic stroma, and other epithelia. A null mutation was introduced into the Matriptase\\/MT-SP1 gene of mice to determine the role of Matriptase\\/MT-SP1 in epidermal development and neoplasia. Matriptase\\/MT-SP1-deficient mice developed to term but uniformly died within 48 h of birth. All epidermal surfaces

Karin List; Christian C Haudenschild; Roman Szabo; WanJun Chen; Sharon M Wahl; William Swaim; Lars H Engelholm; Niels Behrendt; Thomas H Bugge

2002-01-01

187

SYSTEMATIC RNAi STUDIES ON THE ROLE OF Sp/KLF FACTORS IN GLOBIN GENE EXPRESSION AND ERYTHROID DIFFERENTIATION  

PubMed Central

Summary Sp/KLF family of factors regulates gene expression by binding to the CACCC/GC/GT boxes in the DNA through their highly conserved three zinc finger domains. To investigate the role of this family of factors in erythroid differentiation and globin gene expression, we first measured the expression levels of selected Sp/KLF factors in primary cells of fetal and adult stages of erythroid development. This quantitative analysis revealed that their expression levels vary significantly in cells of either stages of the erythroid development. Significant difference in their expression levels was observed between fetal and adult erythroid cells for some Sp/KLF factors. Functional studies using RNA interference revealed that the silencing of Sp1 and KLF8 resulted in elevated level of ? globin expression in K562 cells. In addition, K562 cells become visibly red after Sp1 knockdown. Benzidine staining revealed significant hemoglobinization of these cells, indicating erythroid differentiation. Moreover, the expression of PU.1, ETS1 and Notch1 is significantly down-regulated in the cells that underwent erythroid differentiation following Sp1 knockdown. Overexpression of PU.1 or ETS1 efficiently blocked the erythroid differentiation caused by Sp1 knockdown in K562 cells. The expression of c-Kit, however, was significantly upregulated. These data indicate that Sp1 may play an important role in erythroid differentiation.

Hu, Jie Hong; Navas, Patrick; Cao, Hua; Stamatoyannopoulos, George; Song, Chao-Zhong

2007-01-01

188

ER?-dependent effects on uterine endothelial cells are cell specific and mediated via Sp1  

PubMed Central

STUDY QUESTION What are the in vitro effects of estrogen receptor ? (ER?) activation on the function of endothelial cells (ECs) from different vascular beds: human endometrial ECs (HEECs; endometrium), uterine myometrial microvascular ECs (UtMVECs; myometrium) and human umbilical vein ECs (HUVECs)? SUMMARY ANSWER Studies conducted in vitro demonstrate that the ER? agonist 2,3-bis(4-hydroxy-phenyl)-propionitrile (DPN) has EC type-specific effects on patterns of gene expression and network formation. Identification of a key role for the transcription factor Sp1 in ER?-dependent signaling in uterine ECs offers new insights into cell-specific molecular mechanisms of estrogen action in the human uterus. WHAT IS KNOWN ALREADY Estrogens, acting via ERs (ER? and ER?), have important, body-wide impacts on the vasculature. The human uterus is an estrogen target organ, the endometrial lining of which exhibits physiological, cyclical angiogenesis. In fixed tissue sections, human endometrial ECs are immunopositive for ER?. STUDY DESIGN, SIZE, DURATION Cells were treated with a vehicle control or the ER? agonist, DPN, for 2 h or 24 h (n = 5) followed by gene expression analysis. Functional assays were analyzed after a 16 h incubation with ligand (n = 5). PARTICIPANT/MATERIALS, SETTING, METHODS Analysis of DPN-treated ECs using Taqman gene array cards focused on genes involved in angiogenesis and inflammation identified cell type-specific ER?-dependent changes in gene expression, with validation using qPCR and immunohistochemistry. Molecular mechanisms involved in ER? signaling were investigated using bioinformatics, reporter assays, immunoprecipitation, siRNA and a specific inhibitor blocking Sp1-binding sites. The endometrium and myometrium from women with regular menses were used to validate the protein expression of candidate genes. MAIN RESULTS AND THE ROLE OF CHANCE HEECs and UtMVECs were ER?+/ER??. Treatment of ECs with DPN had opposite effects on network formation: a decrease in network formation in HEECs (P ? 0.001) but an increase in UtMVECs (P ? 0.05). Genomic analysis identified opposite changes in ER? target gene expression with only three common transcripts (HEY1, ICAM1, CASP1) in all three ECs; a unique profile was observed for each. An important role for Sp1 was identified, consistent with the regulation of ER? target genes via association with the transcription factor (‘tethered’ mechanism). LIMITATIONS, REASONS FOR CAUTION The study was mainly carried out in vitro using ECs of which one type was immortalized. Although the analysis of the protein expression of candidate genes was carried out using intact tissue samples from patients, investigations into in vivo angiogenesis were not carried out. WIDER IMPLICATIONS OF THE FINDINGS These results have implications for our understanding of the mechanisms responsible for ER?-dependent changes in EC gene expression in hormone-dependent disorders. STUDY FUNDING/COMPETEING INTEREST(S) The study was funded by a Medical Research Council Programme Grant. E.G. is the recipient of an MRC Career Development Fellowship. The authors have nothing to disclose.

Greaves, Erin; Collins, Frances; Critchley, Hilary O.D.; Saunders, Philippa T.K.

2013-01-01

189

Placental proteins (SP 1 , hCG, PP 5 ), and ? 2 PAG in trophoblastic diseases  

Microsoft Academic Search

Summary 455 serial serum samples from 41 patients with trophoblastic tumour were analysed. Pregnancy-specific beta-1 glycoprotein (SP1), human chorionic gonadotropin (hCG), and placental protein 5 (PP5) were measured by specific radioimmunoassay. Pregnancy-associated ?2-glycoprotein (?2-PAG) was measured by electroimmunoassay. SP1 and hCG levels were high in 36 and 35 patients respectively; ?2-PAG concentration was also high in 29 patients. PP5 was

G. N. Than; H. Bohn; I. F. Csaba; D. G. Szabó; N. J. Karg; P. Göcze

1981-01-01

190

Sp1 and TAFII130 Transcriptional Activity Disrupted in Early Huntington's Disease  

Microsoft Academic Search

Huntington's disease (HD) is an inherited neurodegenerative disease caused by expansion of a polyglutamine tract in the huntingtin protein. Transcriptional dysregulation has been implicated in HD pathogenesis. Here, we report that huntingtin interacts with the transcriptional activator Sp1 and coactivator TAFII130. Coexpression of Sp1 and TAFII130 in cultured striatal cells from wild-type and HD transgenic mice reverses the transcriptional inhibition

Anthone W. Dunah; Hyunkyung Jeong; April Griffin; Yong-Man Kim; David G. Standaert; Steven M. Hersch; M. Maral Mouradian; Anne B. Young; Naoko Tanese; Dimitri Krainc

2002-01-01

191

CLONING OF THE HUMAN ACTIVATED LEUKOCYTE CELL ADHESION MOLECULE PROMOTER AND IDENTIFICATION OF ITS TISSUE-INDEPENDENT TRANSCRIPTIONAL ACTIVATION BY Sp1  

PubMed Central

Activated leukocyte cell adhesion molecule (ALCAM) belongs to the immunoglobulin cell adhesion molecule super family. ALCAM is implicated in tumor progression, inflammation, and the differentiation of hematopoietic stem cells. Hitherto, the identity of regulatory DNA elements and cognate transcription factors responsible for ALCAM gene expression remained unknown. In this report, the human ALCAM promoter was cloned and its transcriptional mechanisms elucidated. The promoter is TATA-less and contains multiple GC-boxes. A proximal 650-bp promoter fragment conferred tissue-independent activation, whereas two contiguous regions upstream of this region negatively influenced promoter activity in a tissue-specific manner. The positive regulatory promoter region was mapped to a core 50 base pair sequence containing a conical Sp1 element. Mutation analysis revealed that this element alone or in tandem with elements immediately upstream was required for maximal promoter activity. Chromatin analysis revealed that Sp1 binds exclusively to the canonical binding sequence in vivo, but not to DNA sequence immediately upstream. Finally, we showed that over-expression of Sp1 significantly increased the basal promoter activity. Thus, Sp1 activated the ALCAM promoter in most cells. These findings have important ramifications for unraveling the roles of ALCAM in inflammation and tumorigenesis.

TAN, FANG; MBUNKUI, FLAUBERT; OFORI-ACQUAH, SOLOMON F.

2013-01-01

192

Shadow Play  

ERIC Educational Resources Information Center

A bunny rabbit playfully hops across the wall. Then hands realign and fingers shift to make a hawk soar toward the ceiling. Most children have enjoyed the delightful experience of playing with shadow puppets. The authors build on this natural curiosity to help students link shadows to complex astronomical concepts such as seasons. The…

Trundle, Kathy Cabe; Hilson, Margilee P.

2012-01-01

193

Shadow Play  

ERIC Educational Resources Information Center

|A bunny rabbit playfully hops across the wall. Then hands realign and fingers shift to make a hawk soar toward the ceiling. Most children have enjoyed the delightful experience of playing with shadow puppets. The authors build on this natural curiosity to help students link shadows to complex astronomical concepts such as seasons. The…

Trundle, Kathy Cabe; Hilson, Margilee P.

2012-01-01

194

Playing as \\  

Microsoft Academic Search

Playing as an evil character is an option available in a number of video games. Both single player games and MMOs support this choice. What motivations, then, do players have for taking this option? This research project includes a study of fifteen individuals who have played as both good and evil characters in either single player games or MMOs. Their

195

Why Play?  

ERIC Educational Resources Information Center

|This paper draws together briefly theories and knowledge from research in morphology and cognitive psychology, as well as some hypothetical information from traditional psychiatry, to show the ramifications of play in children's development. Play is defined as any of a wide variety of behaviors through which an individual attempts to discover…

Weininger, O.

196

Why people continue to play online games: in search of critical design factors to increase customer loyalty to online contents.  

PubMed

As people increasingly play online games, numerous new features have been proposed to increase players' log-on time at online gaming sites. However, few studies have investigated why people continue to play certain online games or which design features are most closely related to the amount of time spent by players at particular online gaming sites. This study proposes a theoretical model using the concepts of customer loyalty, flow, personal interaction, and social interaction to explain why people continue to play online network games. The study then conducts a large-scale survey to validate the model. Finally, it analyzes current online games to identify design features that are closely related to the theoretical concepts. The results indicate that people continue to play online games if they have optimal experiences while playing the games. This optimal experience can be attained if the player has effective personal interaction with the system or pleasant social interactions with other people connected to the Internet. Personal interaction can be facilitated by providing appropriate goals, operators and feedback; social interaction can be facilitated through appropriate communication places and tools. This paper ends with the implications of applying the study results to other domains such as e-commerce and cyber communities. PMID:15006164

Choi, Dongseong; Kim, Jinwoo

2004-02-01

197

Shadow Play  

ERIC Educational Resources Information Center

Discusses the use of shadows to explain such scientific phenomena as umbra and penumbra, eclipses, day and night, seasons, and length of day. Indicates that shadow plays can serve to help the students in understanding more about light. (CC)

Ward, Alan

1974-01-01

198

On the role of the SP1 domain in HIV-1 particle assembly: a molecular switch?  

PubMed

Expression of a retroviral protein, Gag, in mammalian cells is sufficient for assembly of immature virus-like particles (VLPs). VLP assembly is mediated largely by interactions between the capsid (CA) domains of Gag molecules but is facilitated by binding of the nucleocapsid (NC) domain to nucleic acid. We have investigated the role of SP1, a spacer between CA and NC in HIV-1 Gag, in VLP assembly. Mutational analysis showed that even subtle changes in the first 4 residues of SP1 destroy the ability of Gag to assemble correctly, frequently leading to formation of tubes or other misassembled structures rather than proper VLPs. We also studied the conformation of the CA-SP1 junction region in solution, using both molecular dynamics simulations and circular dichroism. Consonant with nuclear magnetic resonance (NMR) studies from other laboratories, we found that SP1 is nearly unstructured in aqueous solution but undergoes a concerted change to an ?-helical conformation when the polarity of the environment is reduced by addition of dimethyl sulfoxide (DMSO), trifluoroethanol, or ethanol. Remarkably, such a coil-to-helix transition is also recapitulated in an aqueous medium at high peptide concentrations. The exquisite sensitivity of SP1 to mutational changes and its ability to undergo a concentration-dependent structural transition raise the possibility that SP1 could act as a molecular switch to prime HIV-1 Gag for VLP assembly. We suggest that changes in the local environment of SP1 when Gag oligomerizes on nucleic acid might trigger this switch. PMID:21325421

Datta, Siddhartha A K; Temeselew, Lakew G; Crist, Rachael M; Soheilian, Ferri; Kamata, Anne; Mirro, Jane; Harvin, Demetria; Nagashima, Kunio; Cachau, Raul E; Rein, Alan

2011-02-16

199

Endothelin-1 stimulates cyclin D1 expression in rat cultured astrocytes via activation of Sp1.  

PubMed

Endothelins (ETs), a family of vasoconstrictor peptides, are up-regulated in several pathological conditions in the brain, and induce astrocytic proliferation. We previously observed that ET-1 increased the expression of cyclin D1 protein. Thus, we confirmed the intracellular up-regulation of cyclin D1 by ET-1 in rat cultured astrocytes. Real-time PCR analysis indicated that ET-1 (100 nM) and Ala(1,3,11,15)-ET-1 (100 nM), a selective agonist of the ETB receptor, induced a time-dependent and transient increase in cyclin D1 mRNA. The effect of ET-1 was diminished by an ETB antagonist (1 ?M BQ788) or inhibitors of Sp1 (500 nM mithramycin), ERK (50 ?M PD98059), p38 (20 ?M SB203580) and JNK (1 ?M SP600125), but not inhibitors of NF-?B (10 ?M SN50 and 100 ?M pyrrolidine dithiocarbamate). The binding assay for Sp1 indicated that ET-1 increased the binding activity of Sp1 to consensus sequences, and two oligonucleotides of the cyclin D1 promoter including the Sp1-binding sites diminished the effect of ET-1. Western blot analysis showed that ET-1 induced time-dependent and transient phosphorylation of Sp1 on Thr453 and Thr739 via the ETB receptor. ET-1-induced phosphorylation of Sp1 was attenuated by PD98059 and SP600125. Additionally, ET-1 increased the incorporation of bromodeoxyuridine (BrdU) in cultured astrocytes and the number of BrdU-positive cells decreased in the presence of PD98059, SP600125 and mithramycin. These results suggest that ET-1 increases the expression of cyclin D1 via activation of Sp1 and induces astrocytic proliferation. PMID:23619396

Michinaga, Shotaro; Ishida, Ayaka; Takeuchi, Risa; Koyama, Yutaka

2013-04-22

200

Play and Positive Group Dynamics  

ERIC Educational Resources Information Center

Play is an important part of a child's life and essential to learning and development (Vygotsky, 1978). It is vital that students participate in play and that play be conducted in a restorative manner. Play allows a variety of group dynamics to emerge. Irvin Yalom (1995) identifies 11 curative factors of the group experience. These factors include…

Thompson, Pam; White, Samantha

2010-01-01

201

Sweet Play  

ERIC Educational Resources Information Center

|This article features Sweet play math, a "math by the month" activity that involves decorating and making sugar cubes. Teachers may want to substitute straws, paper squares, alphabet blocks, or such commercially made manipulatives as Unifix[R] cubes for the real sweets. Given no allergy concerns, teachers and students alike would enjoy some sweet…

Leung, Shuk-kwan S.; Lo, Jane-Jane

2010-01-01

202

Sweet Play  

ERIC Educational Resources Information Center

This article features Sweet play math, a "math by the month" activity that involves decorating and making sugar cubes. Teachers may want to substitute straws, paper squares, alphabet blocks, or such commercially made manipulatives as Unifix[R] cubes for the real sweets. Given no allergy concerns, teachers and students alike would enjoy some sweet…

Leung, Shuk-kwan S.; Lo, Jane-Jane

2010-01-01

203

Clay Play  

ERIC Educational Resources Information Center

This article describes how to use clay as a potential material for young children to explore. As teachers, the authors find that their dialogue about the potential of clay as a learning medium raises many questions: (1) What makes clay so enticing? (2) Why are teachers noticing different play and conversation around the clay table as compared to…

Rogers, Liz; Steffan, Dana

2009-01-01

204

Child's Play  

Microsoft Academic Search

Emerging digital technologies enable teachers and students to access and manipulate sights and sounds in their school environments. The challenge is to systematically include these new media in academic environments, and to include adults who are ill prepared in technical issues as primary guides in this effort. This article suggests that child's play should be the focus of these efforts,

Kristina Woolsey; Matthew Woolsey

2008-01-01

205

Parallel spatial direct numerical simulation of boundary-layer flow transition on IBM SP1  

SciTech Connect

The spatially evolving disturbances that are associated with laminar-to-turbulent transition in three-dimensional boundary-layer flows are computed with the PSDNS code on an IBM SP1 parallel supercomputer. By remapping the distributed data structure during the course of the calculation, optimized serial library routines can be utilized that substantially increase the computational performance. Although the remapping incurs a high communication penalty, the parallel efficiency of the code remains above 40 percent for all performed calculations. By using appropriate compile options and optimized library routines, the serial code achieves 52-56 Mflops on a single node of the SP1 (45 percent of theoretical peak performance). The actual performance of the PSDNS code on the SP1 is evaluated with a ``real world`` simulation that consists of 1.7 million grid points. Comparisons to the Cray Y/MP and Cray C-90 are made for this large scale simulation.

Hanebutte, U.R. [Argonne National Lab., IL (United States); Joslin, R.D. [National Aeronautics and Space Administration, Hampton, VA (United States). Langley Research Center; Zubair, M. [International Business Machines Corp., Yorktown Heights, NY (United States). Thomas J. Watson Research Center

1995-07-01

206

Histone deacetylase 3 represses p15{sup INK4b} and p21{sup WAF1/cip1} transcription by interacting with Sp1  

SciTech Connect

Histone deacetylase 3 (HDAC3) has been implicated to play roles in governing cell proliferation. Here we demonstrated that the overexpression of HDAC3 repressed transcription of p15{sup INK4b} and p21{sup WAF1/cip1} genes in 293T cells, and that the recruitment of HDAC3 to the promoter regions of these genes was critical to this repression. We also showed that HDAC3 repressed GAL4-Sp1 transcriptional activity, and that Sp1 was co-immunoprecipitated with FLAG-tagged HDAC3. We conclude that HDAC3 can repress p15{sup INK4b} and p21{sup WAF1/cip1} transcription by interacting with Sp1. Furthermore, knockdown of HDAC3 by RNAi up-regulated the transcriptional expression of p15{sup INK4b}, but not that of p21{sup WAF1/cip1}, implicating the different roles of HDAC3 in repression of p15{sup INK4b} and p21{sup WAF1/cip1} transcription. Data from this study indicate that the inhibition of p15{sup INK4b} and p21{sup WAF1/cip1} may be one of the mechanisms by which HDAC3 participates in cell cycle regulation and oncogenesis.

Huang Weifeng [Institute of Genetics and Cytology, Northeast Normal University, Changchun 130024 (China); Tan Dapeng [Institute of Genetics and Cytology, Northeast Normal University, Changchun 130024 (China); Wang Xiuli [Institute of Genetics and Cytology, Northeast Normal University, Changchun 130024 (China); Han Songyan [Institute of Genetics and Cytology, Northeast Normal University, Changchun 130024 (China); Tan Jiang [Institute of Genetics and Cytology, Northeast Normal University, Changchun 130024 (China); Zhao Yanmei [Institute of Genetics and Cytology, Northeast Normal University, Changchun 130024 (China); Lu Jun [Institute of Genetics and Cytology, Northeast Normal University, Changchun 130024 (China)]. E-mail: ycsuo@nenu.edu.cn; Huang Baiqu [Institute of Genetics and Cytology, Northeast Normal University, Changchun 130024 (China)

2006-01-06

207

Early experiences with the IBM SP1 and the high-performance switch  

SciTech Connect

The IBM SP1 is IBM`s newest parallel distributed-memory computer. As part of a joint project with IBM, Argonne took delivery of an early system in order to evaluate the software environment and to begin porting programming packages and applications to this machine. This report discusses the results of those efforts once the high-performance switch was installed. An earlier report (ANL/MCS-TM-177) emphasized software usability and the initial ports to the SP1. This report contains performance results and discusses some applications and tools not covered in TM 177.

Gropp, W. [ed.

1993-11-01

208

The Role Played by the Interaction between Genetic Factors and Attachment in the Stress Response in Infancy  

ERIC Educational Resources Information Center

|Background: The importance of understanding which environmental and biological factors are involved in determining individual differences in physiological response to stress is widely recognized, given the impact that stress has on physical and mental health. Methods: The child-mother attachment relationship and some genetic polymorphisms…

Frigerio, Alessandra; Ceppi, Elisa; Rusconi, Marianna; Giorda, Roberto; Raggi, Maria Elisabetta; Fearon, Pasco

2009-01-01

209

Playing Music  

Microsoft Academic Search

\\u000a In this chapter, we show you how to turn your iPad into a great music player. The iPad comes from Apple, which popularized\\u000a electronic music players, so you can bet it has some great capabilities. We will show you how to play and organize the music\\u000a you buy from iTunes or sync from your computer. We will also show to

Martin Trautschold; Gary Mazo

210

Msn2- and Msn4Like Transcription Factors Play No Obvious Roles in the Stress Responses of the Fungal Pathogen Candida albicans  

Microsoft Academic Search

In Saccharomyces cerevisiae, the (C2H2)2 zinc finger transcription factors Msn2 and Msn4 play central roles in responses to a range of stresses by activating gene transcription via the stress response element (STRE; CCCCT). The pathogen Candida albicans displays stress responses that are thought to help it survive adverse environmental conditions encountered within its human host. However, these responses differ from

Susan Nicholls; Melissa Straffon; Brice Enjalbert; A. Nantel; S. Macaskill; M. Whiteway; A. J. P. Brown

2004-01-01

211

The FQPA 10X Safety Factor: How Traditional Risk Assessment Practices Play a Role in Its Application  

Microsoft Academic Search

The history and origin of the 1996 Food Quality Protection Act (FQPA) 10X Safety Factor for infants and children, descriptions of the policy papers issued by the U.S. Environmental Protection Agency (Office of Pesticide Programs) in 1996 and 1998, and the Agency's interoffice 10X Task Force are discussed in this paper. There is an overlap of the FQPA 10X Safety

Susan L. Makris

1999-01-01

212

The study of capacity fading processes of Li-ion batteries: major factors that play a role  

Microsoft Academic Search

In this work, we studied the impact of some factors on the behavior of practical electrodes of Li-ion batteries. These included elevated temperatures (45–80°C), prolonged storage of Li-ion cells, and additives in the electrolyte solution. The Li-ion battery systems studied included negative electrodes (anodes) comprising of mesocarbon microbeads (MCMB) and mesocarbon fibers (MCF), and LixCoO2 positive electrodes (cathodes) in an

B Markovsky; A Rodkin; Y. S Cohen; O Palchik; E Levi; D Aurbach; H.-J Kim; M Schmidt

2003-01-01

213

Characterization of the role of Sp1 and NF-Y in differential regulation of PTTG/securin expression in tumor cells.  

PubMed

Pituitary tumor transforming gene (PTTG), also known as securin, is a regulator of cell division that is overexpressed in many tumors. Its expression is cell cycle regulated, although its transcriptional regulation is yet to be determined. The 5' RACE analysis of the human testis mRNA revealed the existence of a previously unreported transcription start site at 317 bp upstream of the translation start site (ATG). This gene is known to be composed of five exons and four introns, which is now changed to six exons and five introns. To map the promoter region, and to understand its regulation, we designed several fusion constructs of the 5' flanking region of PTTG including the sequence from nucleotide -1373 to -3 (relative to the translation start site) to a luciferase reporter gene. Transient transfection of these constructs in prostate cancer cell line (PC-3) and fibroblast cell line (HS27) confirmed the existence of promoter for PTTG between nucleotides -161 and -3 (in relation to translation start site). The 5' and 3' deletion analysis of the PTTG flanking region and electrophoretic mobility shift assays revealed binding of Sp1 and NF-Y transcription factors within nucleotides -540 to -500. Chromatin immunoprecipitation (ChIP) assays of the HS27 and PC-3 cells revealed the binding of Sp1 protein to PTTG promoter sequence in vivo. Site-directed mutagenesis of the Sp1 consensus sequence resulted in approximately 70% reduction of the overall transcriptional activation of the PTTG promoter, whereas mutation of the NF-Y sequence resulted in approximately 25% reduction. Deletion of both Sp1 and NF-Y consensus sequences resulted in 90% loss of PTTG promoter activity. It was further observed, by Western blot analysis, that the levels of Sp1 protein are higher in PC-3 cells when compared to levels in HS27 cells, possibly contributing to a tissue-specific effect. Our studies indicate an important role of Sp1 in transcription regulation of PTTG expression in tumors. PMID:14644503

Clem, Amy L; Hamid, Tariq; Kakar, Sham S

2003-12-11

214

Hypoxia inducible factor 3? plays a critical role in alveolarization and distal epithelial cell differentiation during mouse lung development.  

PubMed

Lung development occurs under relative hypoxia and the most important oxygen-sensitive response pathway is driven by Hypoxia Inducible Factors (HIF). HIFs are heterodimeric transcription factors of an oxygen-sensitive subunit, HIF?, and a constitutively expressed subunit, HIF1?. HIF1? and HIF2?, encoded by two separate genes, contribute to the activation of hypoxia inducible genes. A third HIF? gene, HIF3?, is subject to alternative promoter usage and splicing, leading to three major isoforms, HIF3?, NEPAS and IPAS. HIF3? gene products add to the complexity of the hypoxia response as they function as dominant negative inhibitors (IPAS) or weak transcriptional activators (HIF3?/NEPAS). Previously, we and others have shown the importance of the Hif1? and Hif2? factors in lung development, and here we investigated the role of Hif3? during pulmonary development. Therefore, HIF3? was conditionally expressed in airway epithelial cells during gestation and although HIF3? transgenic mice were born alive and appeared normal, their lungs showed clear abnormalities, including a post-pseudoglandular branching defect and a decreased number of alveoli. The HIF3? expressing lungs displayed reduced numbers of Clara cells, alveolar epithelial type I and type II cells. As a result of HIF3? expression, the level of Hif2? was reduced, but that of Hif1? was not affected. Two regulatory genes, Rar?, involved in alveologenesis, and Foxp2, a transcriptional repressor of the Clara cell specific Ccsp gene, were significantly upregulated in the HIF3? expressing lungs. In addition, aberrant basal cells were observed distally as determined by the expression of Sox2 and p63. We show that Hif3? binds a conserved HRE site in the Sox2 promoter and weakly transactivated a reporter construct containing the Sox2 promoter region. Moreover, Hif3? affected the expression of genes not typically involved in the hypoxia response, providing evidence for a novel function of Hif3? beyond the hypoxia response. PMID:23451260

Huang, Yadi; Kapere Ochieng, Joshua; Kempen, Marjon Buscop-van; Munck, Anne Boerema-de; Swagemakers, Sigrid; van Ijcken, Wilfred; Grosveld, Frank; Tibboel, Dick; Rottier, Robbert J

2013-02-25

215

Hypoxia Inducible Factor 3? Plays a Critical Role in Alveolarization and Distal Epithelial Cell Differentiation during Mouse Lung Development  

PubMed Central

Lung development occurs under relative hypoxia and the most important oxygen-sensitive response pathway is driven by Hypoxia Inducible Factors (HIF). HIFs are heterodimeric transcription factors of an oxygen-sensitive subunit, HIF?, and a constitutively expressed subunit, HIF1?. HIF1? and HIF2?, encoded by two separate genes, contribute to the activation of hypoxia inducible genes. A third HIF? gene, HIF3?, is subject to alternative promoter usage and splicing, leading to three major isoforms, HIF3?, NEPAS and IPAS. HIF3? gene products add to the complexity of the hypoxia response as they function as dominant negative inhibitors (IPAS) or weak transcriptional activators (HIF3?/NEPAS). Previously, we and others have shown the importance of the Hif1? and Hif2? factors in lung development, and here we investigated the role of Hif3? during pulmonary development. Therefore, HIF3? was conditionally expressed in airway epithelial cells during gestation and although HIF3? transgenic mice were born alive and appeared normal, their lungs showed clear abnormalities, including a post-pseudoglandular branching defect and a decreased number of alveoli. The HIF3? expressing lungs displayed reduced numbers of Clara cells, alveolar epithelial type I and type II cells. As a result of HIF3? expression, the level of Hif2? was reduced, but that of Hif1? was not affected. Two regulatory genes, Rar?, involved in alveologenesis, and Foxp2, a transcriptional repressor of the Clara cell specific Ccsp gene, were significantly upregulated in the HIF3? expressing lungs. In addition, aberrant basal cells were observed distally as determined by the expression of Sox2 and p63. We show that Hif3? binds a conserved HRE site in the Sox2 promoter and weakly transactivated a reporter construct containing the Sox2 promoter region. Moreover, Hif3? affected the expression of genes not typically involved in the hypoxia response, providing evidence for a novel function of Hif3? beyond the hypoxia response.

Huang, Yadi; Kapere Ochieng, Joshua; Kempen, Marjon Buscop-van; Munck, Anne Boerema-de; Swagemakers, Sigrid; van IJcken, Wilfred; Grosveld, Frank; Tibboel, Dick; Rottier, Robbert J.

2013-01-01

216

The Sp-family of transcription factors  

Microsoft Academic Search

GC-boxes and related motifs are frequently occurring DNA-elements present in many promoters and enhancers. In contrast to other elements it was generally thought that the transcription factor Sp1 is the only factor acting through these motifs. The cloning of paralogous genes of the Sp1 factor uncovered the existence of a small protein family consisting of Sp1, Sp2, Sp3 and Sp4.

G. Suske

1999-01-01

217

Inheritance and memory of stress-induced epigenome change: roles played by the ATF-2 family of transcription factors  

PubMed Central

Data on the inheritance-of-stress effect have been accumulating and some mechanistic insights, such as epigenetic regulation, have also been suggested. In particular, the modern view of Lamarckian inheritance appears to be affected by the finding that stress-induced epigenetic changes can be inherited. This review summarizes the current data on the inheritance of stress effect and possible mechanisms involved in this process. In particular, we focus on the stress-induced epigenetic changes mediated by the ATF-2 family of transcription factors.

Seong, Ki-Hyeon; Maekawa, Toshio; Ishii, Shunsuke

2012-01-01

218

Involvement of the GC-rich sequence and specific proteins (Sp1/Sp3) in the basal transcription activity of neurogranin gene  

SciTech Connect

Neurogranin (Ng), a neuronal protein implicated in learning and memory, contains a TATA-less promoter. Analysis of 5'-deletion mutations and site-directed mutations of the mouse Ng promoter revealed that a 258 bp 5'-flanking sequence (+3 to +260) conferred the basal transcription activity, and that the GC-rich sequence (+22 to +33) served as an important determinant of the promoter activity. Transient transfection of the Sp1 expression plasmid transactivated the reporter activity in neuroblastoma N2A cells while knocking down of endogenous Sp1 expression resulted in a 2.5-fold reduction of the reporter activity in HEK 293 cells. Exogenous expression of Sp3 in HEK 293 cells, however, repressed the reporter activity by 50%. Nevertheless, by gel shift assays, Sp1 and Sp3 were not found to be responsible for the protein-DNA complexes formed by the GC-rich sequence. Moreover, a nuclear factor from the mouse brain tissues was discovered to bind to multiple AT-rich regions in Ng promoter.

Gui Jingang [Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117543 (Singapore); Song Yan [Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117543 (Singapore); Han, N.-L.R. [Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117543 (Singapore); Zhou Shufeng [Department of Pharmacy, National University of Singapore, 18 Science Drive 4, Singapore 117543 (Singapore); Sheu, F.-S. [Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117543 (Singapore) and University Scholars Program, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260 (Singapore)]. E-mail: dbssfs@nus.edu.sg

2006-06-23

219

Large-Scale Evidence for the Effect of the COLIA1 Sp1 Polymorphism on Osteoporosis Outcomes: The GENOMOS Study  

PubMed Central

Background Osteoporosis and fracture risk are considered to be under genetic control. Extensive work is being performed to identify the exact genetic variants that determine this risk. Previous work has suggested that a G/T polymorphism affecting an Sp1 binding site in the COLIA1 gene is a genetic marker for low bone mineral density (BMD) and osteoporotic fracture, but there have been no very-large-scale studies of COLIA1 alleles in relation to these phenotypes. Methods and Findings Here we evaluated the role of COLIA1 Sp1 alleles as a predictor of BMD and fracture in a multicenter study involving 20,786 individuals from several European countries. At the femoral neck, the average (95% confidence interval [CI]) BMD values were 25 mg/cm 2 (CI, 16 to 34 mg/cm 2) lower in TT homozygotes than the other genotype groups ( p < 0.001), and a similar difference was observed at the lumbar spine; 21 mg/cm 2 (CI, 1 to 42 mg/cm 2), ( p = 0.039). These associations were unaltered after adjustment for potential confounding factors. There was no association with fracture overall (odds ratio [OR] = 1.01 [CI, 0.95 to 1.08]) in either unadjusted or adjusted analyses, but there was a non-significant trend for association with vertebral fracture and a nominally significant association with incident vertebral fractures in females (OR = 1.33 [CI, 1.00 to 1.77]) that was independent of BMD, and unaltered in adjusted analyses. Conclusions Allowing for the inevitable heterogeneity between participating teams, this study—which to our knowledge is the largest ever performed in the field of osteoporosis genetics for a single gene—demonstrates that the COLIA1 Sp1 polymorphism is associated with reduced BMD and could predispose to incident vertebral fractures in women, independent of BMD. The associations we observed were modest however, demonstrating the importance of conducting studies that are adequately powered to detect and quantify the effects of common genetic variants on complex diseases.

Ralston, Stuart H; Uitterlinden, Andre G; Brandi, Maria Luisa; Balcells, Susana; Langdahl, Bente L; Lips, Paul; Lorenc, Roman; Obermayer-Pietsch, Barbara; Scollen, Serena; Bustamante, Mariona; Husted, Lise Bjerre; Carey, Alisoun H; Diez-Perez, Adolfo; Dunning, Alison M; Falchetti, Alberto; Karczmarewicz, Elzbieta; Kruk, Marcin; van Leeuwen, Johannes P. T. M.; van Meurs, Joyce B. J.; Mangion, Jon; McGuigan, Fiona E. A; Mellibovsky, Leonardo; del Monte, Francesca; Pols, Huibert A. P; Reeve, Jonathan; Reid, David M; Renner, Wilfried; Rivadeneira, Fernando; van Schoor, Natasja M.; Sherlock, Rachael E; Ioannidis, John P. A

2006-01-01

220

Macrophage Migration Inhibitory Factor in the Paraventricular Nucleus Plays a Major Role in the Sympathoexcitatory Response to Salt  

PubMed Central

Central hyperosmotic stimulation (HS) evokes increases in sympathetic nerve activity mediated by activation of angiotensin type 1 receptors in the hypothalamic paraventricular nucleus (PVN). Macrophage inhibitory migration factor (MIF) is an intracellular inhibitory regulator of angiotensin type 1 receptor–mediated actions of angiotensin II within neurons of the PVN. MIF mediates its actions via its intrinsic thiol-protein oxidoreductase activity. We demonstrate that intracerebroventricular injection of hypertonic saline into Sprague-Dawley rats elicits a significant (?112%) increase in MIF mRNA expression in the PVN. Next, we evaluated the effect of viral-mediated expression of either MIF or [C60S]-MIF (which lacks thiol-protein oxidoreductase activity) in the PVN on the sympathoexcitation evoked by HS. We used a decorticate, arterially perfused in situ preparation of male Wistar rats (60 to 80 g). HS was induced by raising perfusate osmolality from 290 to 380 milliosmoles for 40 seconds. Seven to 10 days before experiments, rats were injected bilaterally (500 nL per side) with 0.9% saline (control) or with adenoassociated virus to express MIF, [C60S]-MIF, or enhanced green fluorescent protein in the PVN. HS produced sympathoexcitation in both the 0.9% saline and enhanced green fluorescent protein groups (sympathetic nerve activity increase of +27±4% and +25±4%, respectively; P<0.05), an effect that was not observed in the MIF group (+4±5%). Conversely, the HS-induced increase in sympathetic nerve activity was potentiated in the [C60S]-MIF group (+45±6%; P<0.05). We propose that MIF acting within the PVN is a major counterregulator of HS-induced sympathoexcitation, an effect that depends on thiol-protein oxidoreductase activity.

Colombari, Eduardo; Colombari, Debora S.A.; Li, Hongwei; Shi, Peng; Dong, Ying; Jiang, Nan; Raizada, Mohan K.; Sumners, Colin; Murphy, David; Paton, Julian F.R.

2011-01-01

221

Corticotropin Releasing Factor-Induced Amygdala Gamma-Aminobutyric Acid Release Plays a Key Role in Alcohol Dependence  

PubMed Central

Background Corticotropin-releasing factor (CRF) and gamma-aminobutyric acid (GABA)ergic systems in the central amygdala (CeA) are implicated in the high-anxiety, high-drinking profile associated with ethanol dependence. Ethanol augments CeA GABA release in ethanol-naive rats and mice. Methods Using naive and ethanol-dependent rats, we compared electrophysiologic effects and interactions of CRF and ethanol on CeA GABAergic transmission, and we measured GABA dialyzate in CeA after injection of CRF1 antagonists and ethanol. We also compared mRNA expression in CeA for CRF and CRF1 using real-time polymerase chain reaction. We assessed effects of chronic treatment with a CRF1 antagonist on withdrawal-induced increases in alcohol consumption in dependent rats. Results CRF and ethanol augmented CeA GABAergic transmission in naive rats via increased GABA release. Three CRF1 receptor (CRF1) antagonists decreased basal GABAergic responses and abolished ethanol effects. Ethanol-dependent rats exhibited heightened sensitivity to CRF and CRF1 antagonists on CeA GABA release. Intra-CeA CRF1 antagonist administration reversed dependence–related elevations in GABA dialysate and blocked ethanol-induced increases in GABA dialyzate in both dependent and naive rats. Polymerase chain reaction studies indicate increased expression of CRF and CRF1 in CeA of dependent rats. Chronic CRF1 antagonist treatment blocked withdrawal-induced increases in alcohol drinking by dependent rats and tempered moderate increases in alcohol consumption by nondependent rats in intermittent testing. Conclusions These combined findings suggest a key role for specific presynaptic CRF-GABA interactions in CeA in the development and maintenance of ethanol dependence.

Roberto, Marisa; Cruz, Maureen T.; Gilpin, Nicholas W.; Sabino, Valentina; Schweitzer, Paul; Bajo, Michal; Cottone, Pietro; Madamba, Samuel G.; Stouffer, David G.; Zorrilla, Eric P.; Koob, George F.; Siggins, George R.; Parsons, Loren H.

2010-01-01

222

Intervention in genotoxic stress-induced senescence by cordycepin through activation of eIF2? and suppression of Sp1.  

PubMed

In this study, we show that cordycepin (3'-deoxyadenosine), a major nucleoside isolated from Cordyceps species, attenuates genotoxic stress-induced senescence. Etoposide- or doxorubicin-treated cells exhibited senescent morphology, growth arrest, and positive staining for senescence-associated ?-galactosidase. The induction of the senescent phenotype was inhibited by the treatment of cordycepin. This suppression was correlated with blunted activation of the p16(INK4a) and p21(WAF1/CIP1) gene promoters, as well as a decreased level of p21 (WAF1/CIP1) mRNA. Other adenosine-related substances including ATP, ADP, and adenosine did not mimic the suppressive effect of cordycepin. The antisenescence effect of cordycepin was mediated by activation of eukaryotic translation initiation factor 2? (eIF2?) because (1) cordycepin induced phosphorylation of eIF2?, (2) selective activation of eIF2? mimicked the suppressive effect of cordycepin on senescence, and (3) functional knockdown of eIF2? reversed the effect of cordycepin. Unexpectedly, induction of p53 by etoposide was not inhibited by cordycepin, whereas (1) expression of Sp1 (required for the induction of p21(WAF1/CIP1) and activation of p16(INK4a) by genotoxic stress) was attenuated by cordycepin, (2) DNA binding activity of Sp1 was also inhibited, and (3) selective inhibition of Sp1 reproduced the suppressive effect of cordycepin on senescence. These results suggest that cordycepin interferes with senescence signaling via activation of eIF2? and suppression of Sp1 without affecting the level of p53. PMID:23690541

Gu, Liubao; Johno, Hisashi; Nakajima, Shotaro; Yoshitomi, Tatsuya; Takahashi, Shuhei; Kitamura, Masanori

2013-05-20

223

p53 Cooperates with Sp1 to Regulate Breed-Dependent Expression of Glucocorticoid Receptor in the Liver of Preweaning Piglets  

PubMed Central

Previous studies indicate that Chinese indigenous pig breeds demonstrate distinct pattern of glucocorticoid receptor (GR) expression, which is associated with their unique growth and metabolic phenotypes. Here we sought to unravel the transcriptional mechanisms underlying the breed-specific hepatic GR expression in preweaning Chinese Erhualian (EHL) and Western Large White (LW) piglets. Total GR mRNA and the predominant GR mRNA variant 1–9/10 were expressed significantly higher in EHL compared with LW piglets (P<0.01), which was associated with more enriched histone H3 acetylation on 1–9/10 promoter (P<0.05). Nuclear content of transcription factor specificity protein 1 (Sp1) was significantly lower in EHL piglets, yet its binding to GR 1–9/10 promoter was significantly higher in EHL piglets, as revealed by chromatin immunoprecipitation assays. Although p53 binding to GR promoter 1–9/10 did not differ between breeds, expression of p53 mRNA and protein, as well as its binding to Sp1, were significantly higher in EHL piglets. Moreover, p53 activator doxorubicin significantly enhanced GR 1–9/10 promoter activity in HepG2 cells at 100 nM, which was associated with significantly higher protein content of p53 and GR. Sp1 inhibitor, mithramycin A, significantly inhibited (P<0.05) the basal activity of GR promoter 1–9/10 and completely blocked doxorubicin -induced activation of GR promoter 1–9/10. These data indicate that higher hepatic GR expression in EHL piglets attributes mainly to the enhanced transcription of GR promoter 1–9/10, which is achieved from breed-specific interaction of p53 and Sp1 on porcine GR 1–9/10 promoter.

Li, Runsheng; Jia, Yimin; Yang, Xiaojing; Ni, Yingdong; Zhao, Ruqian

2013-01-01

224

Human glycolipid transfer protein gene (GLTP) expression is regulated by Sp1 and Sp3: involvement of the bioactive sphingolipid ceramide.  

PubMed

Glycolipid transfer protein (GLTP) accelerates glycolipid intermembrane transfer via a unique lipid transfer/binding fold (GLTP fold) that defines the GLTP superfamily and is the prototype for functional GLTP-like domains in larger proteins, i.e. FAPP2. Human GLTP is encoded by the single-copy GLTP gene on chromosome 12 (12q24.11 locus), but regulation of GLTP gene expression remains completely unexplored. Herein, the ability of glycosphingolipids (and their sphingolipid metabolites) to regulate the transcriptional expression of GLTP via its promoter has been evaluated. Using luciferase and GFP reporters in concert with deletion mutants, the constitutive and basal (225 bp; ?78% G+C) human GLTP promoters have been defined along with adjacent regulatory elements. Despite high G+C content, translational regulation was not evident by the mammalian target of rapamycin pathway. Four GC-boxes were shown to be functional Sp1/Sp3 transcription factor binding sites. Mutation of one GC-box was particularly detrimental to GLTP transcriptional activity. Sp1/Sp3 RNA silencing and mithramycin A treatment significantly inhibited GLTP promoter activity. Among tested sphingolipid analogs of glucosylceramide, sulfatide, ganglioside GM1, ceramide 1-phosphate, sphingosine 1-phosphate, dihydroceramide, sphingosine, only ceramide, a nonglycosylated precursor metabolite unable to bind to GLTP protein, induced GLTP promoter activity and raised transcript levels in vivo. Ceramide treatment partially blocked promoter activity decreases induced by Sp1/Sp3 knockdown. Ceramide treatment also altered the in vivo binding affinity of Sp1 and Sp3 for the GLTP promoter and decreased Sp3 acetylation. This study represents the first characterization of any Gltp gene promoter and links human GLTP expression to sphingolipid homeostasis through ceramide. PMID:20974858

Zou, Xianqiong; Gao, Yongguang; Ruvolo, Vivian R; Gardner, Tawnya L; Ruvolo, Peter P; Brown, Rhoderick E

2010-10-25

225

Genome sequence of Enterobacter sp. strain SP1, an endophytic nitrogen-fixing bacterium isolated from sugarcane.  

PubMed

Enterobacter sp. strain SP1 is an endophytic nitrogen-fixing bacterium isolated from a sugarcane stem and can promote plant growth. The draft genome sequence of strain SP1 presented here will promote comparative genomic studies to determine the genetic background of interactions between endophytic enterobacteria and plants. PMID:23209221

Zhu, Bo; Chen, Mingyue; Lin, Li; Yang, Litao; Li, Yangrui; An, Qianli

2012-12-01

226

Aspen SP1, an exceptional thermal, protease and detergent-resistant self-assembled nano-particle.  

PubMed

Stable protein 1 (SP1) is a homo-oligomeric protein isolated from aspen (Populus tremula aspen) plants which forms a ring-shape dodecameric particle with a central cavity. The oligomeric form of SP1 is an exceptionally stable structure that is resistant to proteases (e.g., trypsin, V8, and proteinase K), high temperatures, organic solvents, and high levels of ionic detergent. Analytical ultra-centrifugation, chemical cross-linking, matrix-assisted laser-desorption time-of-flight mass spectrometry (MALDI-TOF-MS), and transmission electron microscopy were used to further characterize the SP1 dodecamer. Introduction of a single cysteine at the N-terminus of SP1 enabled the formation of disulfide bridges within the SP1 dodecamer, concurrent with increased melting point. A six-histidine tag was introduced at the N-terminus of SP1 to generate 6HSP1, and the DeltaNSP1 mutant was generated by a deletion of amino acids 2-6 at the N-terminus. Both 6HSP1 and DeltaNSP1 maintained their ability to assemble a stable dodecamer. Remarkably, these SP1 homo-dodecamers were able to re-assemble into stable hetero-dodecamers following co-electro-elution from SDS-PAGE. The exceptional stability of the SP1-nano ring and its ability to self-assemble hetero-complexes paves the way to further research in utilizing this unique protein in nano-biotechnology. PMID:16732592

Wang, Wang-Xia; Dgany, Or; Wolf, Sharon Grayer; Levy, Ilan; Algom, Rachel; Pouny, Yehonathan; Wolf, Amnon; Marton, Ira; Altman, Arie; Shoseyov, Oded

2006-09-01

227

Identification of functional TFAP2A and SP1 binding sites in new TFAP2A-modulated genes  

PubMed Central

Background Different approaches have been developed to dissect the interplay between transcription factors (TFs) and their cis-acting sequences on DNA in order to identify TF target genes. Here we used a combination of computational and experimental approaches to identify novel direct targets of TFAP2A, a key TF for a variety of physiological and pathological cellular processes. Gene expression profiles of HeLa cells either silenced for TFAP2A by RNA interference or not were previously compared and a set of differentially expressed genes was revealed. Results The regulatory regions of 494 TFAP2A-modulated genes were analyzed for the presence of TFAP2A binding sites, employing the canonical TFAP2A Positional Weight Matrix (PWM) reported in Jaspar http://jaspar.genereg.net/. 264 genes containing at least 2 high score TFAP2A binding sites were identified, showing a central role in "Cellular Movement" and "Cellular Development". In an attempt to identify TFs that could cooperate with TFAP2A, a statistically significant enrichment for SP1 binding sites was found for TFAP2A-activated but not repressed genes. The direct binding of TFAP2A or SP1 to a random subset of TFAP2A-modulated genes was demonstrated by Chromatin ImmunoPrecipitation (ChIP) assay and the TFAP2A-driven regulation of DCBLD2/ESDN/CLCP1 gene studied in details. Conclusions We proved that our computational approaches applied to microarray selected genes are valid tools to identify functional TF binding sites in gene regulatory regions as confirmed by experimental validations. In addition, we demonstrated a fine-tuned regulation of DCBLD2/ESDN transcription by TFAP2A.

2010-01-01

228

The NF-kappa B and Sp1 motifs of the human immunodeficiency virus type 1 long terminal repeat function as novel thyroid hormone response elements.  

PubMed Central

We report that thyroid hormone (T3) receptor (T3R) can activate the human immunodeficiency virus type 1 (HIV-1) long terminal repeat (LTR). Purified chick T3R-alpha 1 (cT3R-alpha 1) binds as monomers and homodimers to a region in the LTR (nucleotides -104 to -75 [-104/-75]) which contains two tandem NF-kappa B binding sites and to a region (-80/-45) which contains three Sp1 binding sites. In contrast, human retinoic acid receptor alpha (RAR-alpha) and mouse retinoid X receptor beta (RXR-beta) do not bind to these elements. However, RXR-beta binds to these elements as heterodimers with cT3R-alpha 1 and to a lesser extent with RAR-alpha. Gel mobility shift assays also revealed that purified NF-kappa B p50/65 or p50/50 can bind to one but not both NF-kappa B sites simultaneously. Although the binding sites for p50/65, p50/50, and T3R, or Sp1 and T3R, overlap, their binding is mutually exclusive, and with the inclusion of RXR-beta, the major complex is the RXR-beta-cT3R-alpha 1 heterodimer. The NF-kappa B region of the LTR and the NF-kappa B elements from the kappa light chain enhancer both function as T3 response elements (TREs) when linked to a heterologous promoter. The TREs in the HIV-1 NF-kappa B sites appear to be organized as a direct repeat with an 8- or 10-bp gap between the half-sites. Mutations within the NF-kappa B motifs which eliminate binding of cT3R-alpha 1 also abolish stimulation by T3, indicating that cT3R-alpha 1 binding to the Sp1 region does not independently mediate activation by T3. The Sp1 region, however, is converted to a functionally strong TRE by the viral tat factor. These studies indicate that the HIV-1 LTR contains both tat-dependent and tat-independent TREs and reveal the potential for T3R to modulate other genes containing NF-kappa B- and Sp1-like elements. Furthermore, they indicate the importance of other transcription factors in determining whether certain T3R DNA binding sequences can function as an active TRE. Images

Desai-Yajnik, V; Samuels, H H

1993-01-01

229

ELECTROPHORETIC MOBILITY SHIFT ASSAY OF ZINC FINGER PROTEINS: COMPETITION FOR ZN2+ BOUND TO SP1 IN PROTOCOLS INCLUDING EDTA  

PubMed Central

The electrophoretic mobility shift assay (EMSA) offers a principal method to detect specific DNA·protein interactions. As commonly conducted, the reaction and electrophoresis running buffers contain large concentrations of EDTA. EDTA has large affinity for Zn2+ and readily competes with zinc-finger peptides for Zn2+ resulting in protein unfolding. Nevertheless, EMSA is routinely used to detect zinc-finger protein·DNA adducts. This paper examines the chemistry that permits the detection of zinc-finger·DNA complexes in the presence of EDTA, using Zn3-Sp1 and a cognate DNA binding site, GC1. Twice as much adduct was detected when the reaction was conducted in the absence than in the presence of EDTA. The observation of Zn-Sp1·GC1 was shown to depend on three properties: the inertness of Zn-Sp1·GC1 to reaction with EDTA and the comparatively similar rates of reaction of EDTA and GC1 with Zn3-Sp1 under the conditions of the assay that permit some Zn3-Sp1·GC1 to form. Inquiring about the mechanism of stabilization of Zn3-Sp1 by GC1, EDTA readily reacted with Zn3-Sp1 bound to a non-specific DNA, poly(dI-dC). Two structurally similar but oppositely charged chelators, nitrilotriacetate (NTA) and tris-(2-ethylaminoethyl) amine (TREN), that react with free Zn3-Sp1 failed to compete for zinc bound in the Zn3-Sp1·GC-1 adduct. On the basis of these and other results indicated that the stability of Zn3-Sp1·GC-1 has a thermodynamic not a kinetic origin. It is concluded that the observation of zinc finger proteins in the EMSA rests on a fortuitous set of chemical properties that may vary depending on the structures involved.

Kothinti, Rajendra; Tabatabai, Niloofar M.; Petering, David H.

2011-01-01

230

Factoring  

NSDL National Science Digital Library

Test your factoring skills Factors and Multiples Jeopardy How much do you know about factoring and multiples? Play Jeopardy and find out! Prime Factoring Turkey Shoot Blast these turkeys using your factoring skills. Help the Professor Super save the planet by "cooking" the Giant Frozen Turkeys of Destruction. Math Lines 12 X-Factor Shoot the ball at the other factors to get a product of 12. You can also ...

Clark, Mr

2012-10-31

231

HIF-1? depletion results in SP1-mediated cell cycle disruption and alters the cellular response to chemotherapeutic drugs  

PubMed Central

Hypoxia inducible factor (HIF) is the major transcription factor involved in the regulation of the cellular response to hypoxia or low oxygen tensions. Even though HIF-1 function is mostly studied following hypoxic stress, well oxygenated areas of several diseased tissues have detectable levels of this transcription factor. Therefore, it is surprising how little is known about the function of HIF in normoxia. This study seeks to fill this gap. Using transient HIF-1? knockdown, as well as, stable cell lines generated using short hairpin RNAs (shRNA), we have further characterized the role of HIF-1? in normoxia. Our data reveals that knockdown of HIF-1? results in a significant increase in cells in the G1 phase of the cell cycle. We find that HIF-1? depletion increases the protein and mRNA of both p21 and p27. p21 is induced via, at least in part, p53-independent but SP1-dependent mechanisms. Interestingly, HIF-1? knockdown also alters the cellular response to chemotherapeutic agents. These data have important implications in not only for the further understanding of HIF-1?, a major transcription factor, but also for the use of HIF-targeted and combination therapies in cancer treatment.

Culver, Carolyn; Melvin, Andrew; Mudie, Sharon

2011-01-01

232

Nuclear Factor I and Mammary Gland Factor (STAT5) Play a Critical Role in Regulating Rat Whey Acidic Protein Gene Expression in Transgenic Mice  

Microsoft Academic Search

The rat whey acidic protein (WAP) gene contains a mammary gland-specific and hormonally regulated DNase I-hypersensitive site 830 to 720 bp 5*to the site of transcription initiation. We have reported previously that nuclear factor I (NFI) binding at a palindromic site and binding at a half-site are the major DNA-protein interactions detected within this tissue-specific nuclease-hypersensitive region. We now show

SHI LI ANDJEFFREY; M. ROSEN

1995-01-01

233

Role of Rev-erb? domains for transactivation of the connexin43 promoter with Sp1.  

PubMed

Rev-erb?, a component of the circadian clock, has also been known as a nuclear receptor that lacks activation function domain 2, functioning as a ligand-dependent transcriptional repressor. However, we recently reported that Rev-erb? activates connexin43 transcription by forming a complex with Sp1. Here we show that heme, a REV-ERB ligand, is dispensable for this novel mechanism and that Rev-erb?, having homologies with Rev-erb?, does not activate connexin43, but competes with the Rev-erb?/Sp1. The A/B region of Rev-erb?, which is not conserved in Rev-erb?, is a crucial activating domain, while the ligand binding domain, conserved in Rev-erb?, functions as a competitor. PMID:23201262

Negoro, Hiromitsu; Okinami, Takeshi; Kanematsu, Akihiro; Imamura, Masaaki; Tabata, Yasuhiko; Ogawa, Osamu

2012-11-28

234

[SP-1 in normal and complicated early pregnancy. Diagnosis by enzyme immunoassay].  

PubMed

Pregnancy specific glycoprotein SP-1 was measured by enzyme immunoassay Enzygnost in patients with diagnosis of haemorrhage in early pregnancy. Results were compared with a normal range between 6.-22. week of gestation (n = 268) and were analysed for their predictive value in determining prognosis. 24 of 27 cases with levels below the normal range had an abortion (88,9%) while 28 of 31 women with continuing pregnancies had levels within normal range (90,3%). PMID:6347803

Tatra, G; Bernaschek, G; Tessarek, K H

1983-04-01

235

Host Factors LR1 and Sp1 Regulate the Fp Promoter of Epstein-Barr Virus  

Microsoft Academic Search

The Epstein-Barr virus EBNA-1 gene product is essential for latent replication of the virus. In transformed cells characterized by the most restricted patterns of viral latent gene expression, EBNA-1 transcription is driven from the Fp promoter. We have used genetic and biochemical techniques to study the promoter-proximal elements that regulate Fp expression in B cells. We show that a 114-bp

Silvia Bulfone-Paus; Laurie A. Dempsey; Nancy Maizels

1995-01-01

236

Multiple recombining loci encode MaSp1, the primary constituent of dragline silk, in widow spiders (Latrodectus: Theridiidae).  

PubMed

Spiders spin a functionally diverse array of silk fibers, each composed of one or more unique proteins. Most of these proteins, in turn, are encoded by members of a single gene family thought to have arisen through duplication and divergence of an ancestral silk gene. Because of its remarkable mechanical properties, orb weaver dragline silk, a composite of 2 proteins (MaSp1 and MaSp2), is the best studied. Here, we demonstrate that multiple loci encode MaSp1 in widow spiders (Latrodectus). Because these copies may be the result of more recent duplication events than those leading to the currently recognized silk gene paralogs, they offer insight into the early evolutionary fate of silk gene duplicates. In addition to 3 presumed functional MaSp1 loci in Latrodectus hesperus (Western black widow) and Latrodectus geometricus (brown widow) genomes, we find a MaSp1 pseudogene in L. hesperus, demonstrating the potential for unrecognized extinction of silk gene paralogs. We also document recombination events among L. hesperus MaSp1 loci and between Latrodectus MaSp1 loci and MaSp2. This result supports the hypothesis that concerted evolution occurs not only within an individual silk gene but also among silk gene paralogs. One of the L. geometricus MaSp1 copies encodes a protein that has diverged in amino acid composition and potentially converged on the secondary structure of MaSp2. Based on the presence of multiple MaSp1 loci and the phylogenetic distribution of MaSp1 versus MaSp2, we propose that MaSp2 is derived from an ancestral MaSp1 duplicate. Finally, divergence has occurred in the upstream flanking sequences of the L. hesperus MaSp1 loci, the region most likely to contain regulatory motifs, providing ample opportunity for differential expression. However, the benefits associated with increased protein production may be the primary mechanism maintaining multiple functional MaSp1 copies in widow genomes. PMID:18048404

Ayoub, Nadia A; Hayashi, Cheryl Y

2007-11-28

237

Autophagosomal I?B? Degradation Plays a Role in the Long Term Control of Tumor Necrosis Factor-?-induced Nuclear Factor-?B (NF-?B) Activity*  

PubMed Central

Transcription factor NF-?B is persistently activated in many chronic inflammatory diseases and cancers. The short term regulation of NF-?B is well understood, but little is known about the mechanisms of its long term activation. We studied the effect of a single application of TNF-? on NF-?B activity for up to 48 h in intestinal epithelial cells. Results show that NF-?B remained persistently activated up to 48 h after TNF-? and that the long term activation of NF-?B was accompanied by a biphasic degradation of I?B?. The first phase of I?B? degradation was proteasome-dependent, but the second was not. Further investigation showed that TNF-? stimulated formation of autophagosomes in intestinal epithelial cells and that I?B? co-localized with autophagosomal vesicles. Pharmacological or genetic blockade of autophagosome formation or the inhibition of lysosomal proteases decreased TNF-?-induced degradation of I?B? and lowered NF-?B target gene expression. Together, these findings indicate a role of autophagy in the control of long term NF-?B activity. Because abnormalities in autophagy have been linked to ineffective innate immunity, we propose that alterations in NF-?B may mediate this effect.

Colleran, Amy; Ryan, Aideen; O'Gorman, Angela; Mureau, Coralie; Liptrot, Catherine; Dockery, Peter; Fearnhead, Howard; Egan, Laurence J.

2011-01-01

238

Replication Factor C3 of Schizosaccharomyces pombe, a Small Subunit of Replication Factor C Complex, Plays a Role in Both Replication and Damage Checkpoints  

PubMed Central

We report here the isolation and functional analysis of the rfc3+ gene of Schizosaccharomyces pombe, which encodes the third subunit of replication factor C (RFC3). Because the rfc3+ gene was essential for growth, we isolated temperature-sensitive mutants. One of the mutants, rfc3-1, showed aberrant mitosis with fragmented or unevenly separated chromosomes at the restrictive temperature. In this mutant protein, arginine 216 was replaced by tryptophan. Pulsed-field gel electrophoresis suggested that rfc3-1 cells had defects in DNA replication. rfc3-1 cells were sensitive to hydroxyurea, methanesulfonate (MMS), and gamma and UV irradiation even at the permissive temperature, and the viabilities after these treatments were decreased. Using cells synchronized in early G2 by centrifugal elutriation, we found that the replication checkpoint triggered by hydroxyurea and the DNA damage checkpoint caused by MMS and gamma irradiation were impaired in rfc3-1 cells. Association of Rfc3 and Rad17 in vivo and a significant reduction of the phosphorylated form of Chk1 in rfc3-1 cells after treatments with MMS and gamma or UV irradiation suggested that the checkpoint signal emitted by Rfc3 is linked to the downstream checkpoint machinery via Rad17 and Chk1. From these results, we conclude that rfc3+ is required not only for DNA replication but also for replication and damage checkpoint controls, probably functioning as a checkpoint sensor.

Shimada, Midori; Okuzaki, Daisuke; Tanaka, Seiji; Tougan, Takahiro; Tamai, Katsuyuki K.; Shimoda, Chikashi; Nojima, Hiroshi

1999-01-01

239

The TGF-?/Smad Repressor TG-Interacting Factor 1 (TGIF1) Plays a Role in Radiation-Induced Intestinal Injury Independently of a Smad Signaling Pathway  

PubMed Central

Despite advances in radiation delivery protocols, exposure of normal tissues during the course of radiation therapy remains a limiting factor of cancer treatment. If the canonical TGF-?/Smad pathway has been extensively studied and implicated in the development of radiation damage in various organs, the precise modalities of its activation following radiation exposure remain elusive. In the present study, we hypothesized that TGF-?1 signaling and target genes expression may depend on radiation-induced modifications in Smad transcriptional co-repressors/inhibitors expressions (TGIF1, SnoN, Ski and Smad7). In endothelial cells (HUVECs) and in a model of experimental radiation enteropathy in mice, radiation exposure increases expression of TGF-?/Smad pathway and of its target gene PAI-1, together with the overexpression of Smad co-repressor TGIF1. In mice, TGIF1 deficiency is not associated with changes in the expression of radiation-induced TGF-? pathway-related transcripts following localized small intestinal irradiation. In HUVECs, TGIF1 overexpression or silencing has no influence either on the radiation-induced Smad activation or the Smad3-dependent PAI-1 overexpression. However, TGIF1 genetic deficiency sensitizes mice to radiation-induced intestinal damage after total body or localized small intestinal radiation exposure, demonstrating that TGIF1 plays a role in radiation-induced intestinal injury. In conclusion, the TGF-?/Smad co-repressor TGIF1 plays a role in radiation-induced normal tissue damage by a Smad-independent mechanism.

Hneino, Mohammad; Francois, Agnes; Buard, Valerie; Tarlet, Georges; Abderrahmani, Rym; Blirando, Karl; Hoodless, Pamela A.; Benderitter, Marc; Milliat, Fabien

2012-01-01

240

HIF2?-Sp1 interaction mediates a deacetylation-dependent FVII-gene activation under hypoxic conditions in ovarian cancer cells  

PubMed Central

Hypoxia-inducible factors (HIF)-1? and HIF2? are major transcription factors required for adaptive responses to hypoxia. HIFs form a complex with aryl hydrocarbon receptor nuclear translocator (ARNT) to bind to the regulatory regions of target genes. The acetylation of histones by histone acetyltransferases (HATs) is one of the epigenetic marks associated with active chromatin. Indeed, HIFs recruit p300 HAT to hypoxia response elements (HREs) within gene regulatory regions. Here, we report an unusual HIF-mediated transcriptional activation in ovarian clear cell carcinoma (CCC). While characterizing coagulation factor VII (FVII) gene induction during hypoxic conditions, we observed that the interaction of HIF2? with Sp1, but not with ARNT, could induce transcription of FVII in a HRE-independent manner. Unexpectedly, this gene activation is associated with histone deacetylation. We found that a class II HDAC, HDAC4, is recruited with HIF2? to the FVII promoter as a co-activator, while p300 HAT negatively regulated this process. Furthermore, this mechanism can be synergistically enhanced via a deacetylation-dependent pathway when cells are simultaneously exposed to hypoxic and serum-free conditions. These results suggest the presence of a stress-responsive transcription mediated by the HIF2?/Sp1/HDAC4 network and explain how CCC shed their procoagulant activity under hypoxia.

Koizume, Shiro; Ito, Shin; Miyagi, Etsuko; Hirahara, Fumiki; Nakamura, Yoshiyasu; Sakuma, Yuji; Osaka, Hitoshi; Takano, Yasuo; Ruf, Wolfram; Miyagi, Yohei

2012-01-01

241

Multiple SP1 binding sites confer enhancer-independent, replication-activated transcription of HIV-1 and globin gene promoters.  

PubMed

We demonstrate that multiple SP1 protein:DNA binding sites confer enhancer-independent activation on the HIV-1 and globin gene promoters. This activation process can be achieved either by DNA replication of the promoter-containing plasmid or by high concentrations of input plasmid DNA used in the transfections. In the case of HIV-1, the three SP1 sites adjacent to the promoters TATA box are essential for this activation process. Furthermore, the human beta globin gene, which is normally dependent on a linked enhancer for transcriptional activity, can be made enhancer independent by insertion of SP1 binding sites adjacent to its TATA box. We speculate that (SP1)n-TATA type RNA polymerase II promoters may be generally permissive when present on actively replicating DNA templates and that this property of the HIV-1 promoter may be of importance to the activation of the DNA provirus in latently infected T cells. PMID:1622932

Proudfoot, N J; Lee, B A; Monks, J

1992-04-01

242

Target integration by a chimeric Sp1 zinc finger domain-moloney murine leukemia virus integrase in vivo  

Microsoft Academic Search

A specificity protein 1 (Sp1) zinc finger domain containing two tandem zinc fingers was fused to the C terminus of the integrase (IN) protein of the Moloney murine leukemia virus (MuLV). The integrity of the MuLV IN was completely preserved, since the fusion was conducted at the last amino acid residue of the protein. The vector pMIN-Sp1, which carried the

Wen-Jiun Peng; Chau-Ming Chang; Thy-Hou Lin

2002-01-01

243

The ability of C/EBP beta but not C/EBP alpha to synergize with an Sp1 protein is specified by the leucine zipper and activation domain.  

PubMed

The rat CYP2D5 P-450 gene is activated in the liver during postnatal development. We previously showed that liver-specific transcription of the CYP2D5 gene is dictated by a proximal promoter element, termed 2D5, that is composed of a binding site for Sp1 or a related factor, and an adjacent cryptic C/EBP (CCAAT/enhancer-binding protein) site. Despite the fact that both C/EBP alpha and C/EBP beta are expressed abundantly in liver, only C/EBP beta is capable of stimulating the 2D5 promoter in HepG2 hepatocarcinoma cells. In addition, activation of the 2D5 promoter by C/EBP beta is completely dependent on the presence of the Sp1 site. Domain switch experiments reveal that C/EBP beta proteins containing either the leucine zipper or the activation domain of C/EBP alpha are unable to stimulate the 2D5 promoter yet are fully capable of transactivating an artificial promoter bearing a high-affinity C/EBP site. Thus, the leucine zipper and the activation domain of C/EBP beta are absolutely required to support transactivation of the 2D5 promoter. Using Drosophila cells that lack endogenous Sp1 activity, we show that the serine/threonine- and glutamine-rich activation domains A and B of Sp1 are required for efficient cooperatively with C/EBP beta. Furthermore, analysis of c/ebp beta-deficient mice shows that mutant animals are defective in expression of a murine CYP2D5 homolog in hepatic cells, confirming the selective ability of C/EBP beta to activate this liver-specific P-450 gene in vivo. Our findings illustrate that two members of a transcription factor family can achieve distinct target gene specificities through differential interactions with a cooperating Sp1 protein. PMID:9121452

Lee, Y H; Williams, S C; Baer, M; Sterneck, E; Gonzalez, F J; Johnson, P F

1997-04-01

244

CCL19/CCR7 upregulates heparanase via specificity protein-1 (Sp1) to promote invasion of cell in lung cancer.  

PubMed

CCL19/chemokine receptor 7 (CCR7) has been found to be associated with tumor growth, angiogenesis, invasion, and lymph node metastasis. Our previous study demonstrated that CCR7 overexpressed in non-small cell lung cancer (NSCLC) and had close relationship with tumor invasion and lymph node metastasis. However, the molecular mechanism of CCR7 promoting invasion of human NSCLC cells is still unclear. In this study, we demonstrated that human lung adenocarcinoma A549 cells treated with recombinant human CCL19 could obviously upregulate the expression of Sp1 and heparanase at both the mRNA and protein levels. After blockage of CCR7, Sp1 and heparanase expressions were inhibited. Following inhibition of Sp1, heparanase expression was downregulated. The analysis showed the promoter region of heparanase gene containing a number of potential sp1 binding sites (5'-GGGGC-3'). Chromatin immunoprecipitation analysis demonstrated that Sp1 could bind to the heparanase promoter. Cell invasion assays showed that the invasion ability of A549 cells was increased with CCL19 incubation compared to the control cells. These results suggested that CCL19/CCR7 may upregulate the expression of heparanase via Sp1 and contribute to the invasion of A549 cells. PMID:23649655

Zhang, Qingfu; Sun, Limei; Yin, Liying; Ming, Jian; Zhang, Siyang; Luo, Wenting; Qiu, Xueshan

2013-05-07

245

Regulation of the human ascorbate transporter SVCT2 exon 1b gene by zinc-finger transcription factors.  

PubMed

The sodium-dependent vitamin C transporter (SVCT) 2 is crucial for ascorbate uptake in metabolically active and specialized tissues. This study focused on the gene regulation of SVCT2 exon 1b, which is ubiquitously expressed in human and mouse tissues. Although the human SVCT2 exon 1b promoter does not contain a classical TATA box, we found that it does contain a functional initiator that binds Yin Yang-1 (YY1) and interacts with upstream Sp1/Sp3 elements in the proximal promoter region. These elements in turn play a critical role in regulating YY1-mediated transcription of exon 1b. Formation of YY1/Sp complexes on the promoter is required for its optional function. YY1 with Sp1 or Sp3 synergistically enhanced exon 1b promoter activity as well as the endogenous SVCT2 protein expression. Further, in addition to Sp1/Sp3, both EGR-1 and EGR-2 were detected in the protein complexes that bound the three GC boxes bearing overlapping binding sites for EGR/WT1 and Sp1/3. The EGR family factors WT1 and MAZ were found to differentially regulate exon 1b promoter activity. These results show that differential occupancy of transcription factors on the GC-rich consensus sequences in the SVCT2 exon 1b promoter contributes to the regulation of cell and tissue expression of SVCT2. PMID:21335086

Qiao, Huan; May, James M

2011-02-16

246

Genetic Selection for Context-Dependent Stochastic Phenotypes: Sp1 and TATA Mutations Increase Phenotypic Noise in HIV-1 Gene Expression  

PubMed Central

The sequence of a promoter within a genome does not uniquely determine gene expression levels and their variability; rather, promoter sequence can additionally interact with its location in the genome, or genomic context, to shape eukaryotic gene expression. Retroviruses, such as human immunodeficiency virus-1 (HIV), integrate their genomes into those of their host and thereby provide a biomedically-relevant model system to quantitatively explore the relationship between promoter sequence, genomic context, and noise-driven variability on viral gene expression. Using an in vitro model of the HIV Tat-mediated positive-feedback loop, we previously demonstrated that fluctuations in viral Tat-transactivating protein levels generate integration-site-dependent, stochastically-driven phenotypes, in which infected cells randomly ‘switch’ between high and low expressing states in a manner that may be related to viral latency. Here we extended this model and designed a forward genetic screen to systematically identify genetic elements in the HIV LTR promoter that modulate the fraction of genomic integrations that specify ‘Switching’ phenotypes. Our screen identified mutations in core promoter regions, including Sp1 and TATA transcription factor binding sites, which increased the Switching fraction several fold. By integrating single-cell experiments with computational modeling, we further investigated the mechanism of Switching-fraction enhancement for a selected Sp1 mutation. Our experimental observations demonstrated that the Sp1 mutation both impaired Tat-transactivated expression and also altered basal expression in the absence of Tat. Computational analysis demonstrated that the observed change in basal expression could contribute significantly to the observed increase in viral integrations that specify a Switching phenotype, provided that the selected mutation affected Tat-mediated noise amplification differentially across genomic contexts. Our study thus demonstrates a methodology to identify and characterize promoter elements that affect the distribution of stochastic phenotypes over genomic contexts, and advances our understanding of how promoter mutations may control the frequency of latent HIV infection.

Shah, Priya S.; Arkin, Adam P.; Schaffer, David V.

2013-01-01

247

Human ZNF312b oncogene is regulated by Sp1 binding to its promoter region through DNA demethylation and histone acetylation in gastric cancer.  

PubMed

In a previous study, human ZNF312b was identified as a cell proliferation-associated oncogene via the K-ras/extracellular signal-regulated kinase cascade in gastric cancer. However, the mechanism concerning its transcriptional activation remains unknown. Here, we show that DNA methylation and histone acetylation of the ZNF312b promoter function as a switch for ZNF312b transcriptional activation in gastric cancer. The transcription level of ZNF312b was increased by treatment with a demethylating agent, 5-aza-2'-deoxycytidine and the histone deacetylase inhibitor sodium butyrate, in several human cancer cell lines including gastric cancer. Consistent with these results, epigenetic analysis, such as pyrosequencing, bisulfate sequencing and methyl-specific polymerase chain reaction (MSP), showed that the expression level of ZNF312b is highly dependent on the degree of DNA methylation in gastric cancer cell lines. In addition, by ChIP assay using anti-acetyl/methyl H3K9 antibodies, histone acetylation was shown to mediate the expression of the ZNF312b gene. Interestingly, ChIP assay using the Sp1 antibody revealed that the binding of transcription factor Sp1 to the ZNF312b promoter for its transcriptional activation requires DNA demethylation and histone acetylation. Moreover, a knockdown of Sp1 resulted in a decrease in ERK-mediated proliferation via downregulation of the ZNF312b gene in gastric cancer cells. Taken together, these results suggest that the aberrant expression of ZNF312b promotes gastric tumorigenesis through epigenetic modification of its promoter region and provides a molecular mechanism for ZNF312b expression to contribute to the progression of gastric cancer. PMID:21170990

Song, In-Sung; Ha, Ga-Hee; Kim, Jeong-Min; Jeong, So-Young; Lee, Han-Chul; Kim, Yong Sung; Kim, Yung-Jin; Kwon, Taeg Kyu; Kim, Nam-Soon

2011-03-04

248

A Feedback Loop Consisting of MicroRNA 23a/27a and the ?-Like Globin Suppressors KLF3 and SP1 Regulates Globin Gene Expression.  

PubMed

The developmental stage-specific expression of the human ?-like globin genes has been studied for decades, and many transcriptional factors as well as other important cis elements have been identified. However, little is known about the microRNAs that potentially regulate ?-like globin gene expression directly or indirectly during erythropoiesis. In this study, we show that microRNA 23a (miR-23a) and miR-27a promote ?-like globin gene expression in K562 cells and primary erythroid cells through targeting of the transcription factors KLF3 and SP1. Intriguingly, miR-23a and miR-27a further enhance the transcription of ?-like globin genes through repression of KLF3 and SP1 binding to the ?-like globin gene locus during erythroid differentiation. Moreover, KLF3 can bind to the promoter of the miR-23a?27a?24-2 cluster and suppress this microRNA cluster expression. Hence, a positive feedback loop comprised of KLF3 and miR-23a promotes the expression of ?-like globin genes and the miR-23a?27a?24-2 cluster during erythropoiesis. PMID:23918807

Ma, Yanni; Wang, Bin; Jiang, Fengbing; Wang, Dongsheng; Liu, Huiwen; Yan, Yunmeng; Dong, He; Wang, Fang; Gong, Bei; Zhu, Yong; Dong, Lei; Yin, Haixin; Zhang, Zhongzu; Zhao, Hualu; Wu, Zhikui; Zhang, Junwu; Zhou, Jingguo; Yu, Jia

2013-08-05

249

Synthetic retinoid Am80 up-regulates apelin expression by promoting interaction of RAR? with KLF5 and Sp1 in vascular smooth muscle cells.  

PubMed

Previous studies have demonstrated that both retinoids and apelin possess potent cardiovascular properties and that retinoids can mediate the expression of many genes in the cardiovascular system. However, it is not clear whether and how retinoids regulate apelin expression in rat VSMCs (vascular smooth muscle cells). In the present study, we investigated the molecular mechanism of apelin expression regulation by the synthetic retinoid Am80 in VSMCs. The results showed that Am80 markedly up-regulated apelin mRNA and protein levels in VSMCs. Furthermore, KLF5 (Krüppel-like factor 5) and Sp1 (stimulating protein-1) co-operatively mediated Am80-induced apelin expression through their direct binding to the TCE (transforming growth factor-? control element) on the apelin promoter. Interestingly, upon Am80 stimulation, the RAR? (retinoic acid receptor ?) was recruited to the apelin promoter by interacting with KLF5 and Sp1 prebound to the TCE site of the apelin promoter to form a transcriptional activation complex, subsequently leading to the up-regulation of apelin expression in VSMCs. An in vivo study indicated that Am80 increased apelin expression in balloon-injured arteries of rats, consistent with the results from the cultured VSMCs. Thus the results of the present study describe a novel mechanism of apelin regulation by Am80 and further expand the network of RAR? in the retinoid pathway. PMID:23992409

Lv, Xin-Rui; Zheng, Bin; Li, Shu-Ya; Han, Ai-Li; Wang, Chang; Shi, Jian-Hong; Zhang, Xin-Hua; Liu, Yan; Li, Yong-Hui; Wen, Jin-Kun

2013-11-15

250

COL1A1 Sp1 variation and bone phenotypes in an Italian population  

PubMed Central

Summary Background Osteoporosis is the most common metabolic bone disorder of the elderly, affecting the normal bone turnover with an increased bone resorption and subsequent higher risk of fragility fractures. Collagen type 1 is the most represented protein in bone matrix. A genetic variation (Sp1) in intron 1 of COL1A1 gene has been associated to modulation of expression of the alpha 1 chain of collagen type 1 and it is considered a candidate polymorphism for predisposition to osteoporosis status and fragility fractures. Association studies, in ethnically different populations, are needed to strongly confirm the role of this polymorphism in bone metabolism. Materials and methods We enrolled over 2,000 Italian individuals and studied their bone mineral density (BMD) and fractures in relation to age, sex and body mass index (BMI). Moreover, we analyzed the distribution of Sp1 polymorphism in these individuals and associated it to normal bone status, osteopenic condition or osteoporosis diagnosis, BMD and the presence of low-trauma fractures. Results The most rare ss genotype showed a trend for osteoporosis diagnosis with respect to both normal and osteopenic status. The same genotype resulted to be associated to lower values of BMD both at spine and femur sites. No association was found with fractures. Discussion In conclusion the presence of the homozygote ss genotype seemed to predispose to osteoporosis diagnosis and to be more frequent in subjects with lower spine and femur BMD values.

Marini, Francesca; Parri, Simone; Masi, Laura; Ciuffi, Simone; Guazzini, Andrea; Fabbri, Sergio; Luzi, Ettore; Cianferotti, Luisella; Brandi, Maria Luisa

2013-01-01

251

Play School’ – a catalyst for play  

Microsoft Academic Search

The Australian children's television program Play School has been inviting young children to play for 45 years. Based on the original BBC production, Play School has been screened across Australia twice each weekday on the national broadcaster since 1966. Recent developments in early childhood education and care education in Australia have highlighted the importance of play for learning and wellbeing.

Cathie Harrison; Tracy Anderson; Helen van Vliet

2012-01-01

252

The N-terminal 20-amino acid region of guanine nucleotide exchange factor Vav1 plays a distinguished role in T cell receptor-mediated calcium signaling.  

PubMed

Vav1 is a guanine nucleotide exchange factor (GEF) specifically expressed in hematopoietic cells. It consists of multiple structural domains and plays important roles in T cell activation. The other highly conserved isoforms of Vav family, Vav2 and Vav3, are ubiquitously expressed in human tissues including lymphocytes. All three Vav proteins activate Rho family small GTPases, which are involved in a variety of biological processes during T cell activation. Intensive studies have demonstrated that Vav1 is indispensable for T cell receptor (TCR)-mediated signal transduction, whereas Vav2 and Vav3 function as GEFs that overlap with Vav1 on TCR-induced cytoskeleton reorganization. T cells lacking Vav1 exhibited severe defect in TCR-mediated calcium elevation, indicating that the co-existing Vav2 and Vav3 did not compensate Vav1 in calcium signaling. What is the functional particularity of Vav1 in lymphocytes? In this study, we identified the N-terminal 20 amino acids of Vav1 in the calponin homology (CH) domain to be essential for its interaction with calmodulin (CaM) that leads to TCR-induced calcium mobilization. Substitution of the 1-20 amino acids of Vav1 with those of Vav2 or Vav3 abolished the association with CaM, and the N-terminal mutations of Vav1 failed to potentiate normal TCR-induced calcium mobilization, that in turn, suspended nuclear factor of activated T cells (NFAT) activation and IL-2 production. This study highlights the importance of the N-terminal 20 aa of Vav1 for CaM binding, and provides new insights into the distinguished and irreplaceable role of Vav1 in T cell activation and signal transduction. PMID:23271736

Li, Shi-Yang; Du, Ming-Juan; Wan, Ya-Juan; Lan, Bei; Liu, Yao-Hui; Yang, Yin; Zhang, Cui-Zhu; Cao, Youjia

2012-12-27

253

Poly(ADP-ribose) Polymerase 1 Interacts with Nuclear Respiratory Factor 1 (NRF-1) and Plays a Role in NRF-1 Transcriptional Regulation*S?  

PubMed Central

Nuclear respiratory factor 1 (NRF-1) is one of the key transcriptional activators for nuclear-coded genes involved in mitochondrial biogenesis and function as well as for many housekeeping genes. A transcriptional co-activator PGC-1 and its related family member PRC have previously been shown to interact with NRF-1 and co-activate NRF-1. We show here that NRF-1 can also directly interact with poly(ADP-ribose) polymerase 1 (PARP-1) and co-purify the PARP-1·DNA-PK·Ku80·Ku70·topoisomerase II?-containing protein complex. Our in vitro binding experiments show that DNA-binding/dimerization domain of NRF-1 and the N-terminal half of PARP-1, which contains two Zinc fingers and the auto-modification domain, are responsible for the interaction, and that this interaction occurs with or without PARP-1 poly(ADP-ribosyl)ation (PARylation). DNA-bound NRF-1 can form a complex with PARP-1, suggesting that NRF-1 can recruit the PARP-1·DNA-PK·Ku80·Ku70·topoisomerase II?-containing protein complex to the promoter. PARP-1 can also PARylate the DNA-binding domain of NRF-1 and negatively regulate NRF-1·PARP-1 interaction. Transient transfection and chromatin immunoprecipitation experiments suggest that PARP-1 plays a role during transcriptional activation by NRF-1. Our finding identifies a new aspect of transcriptional regulation used by NRF-1.

Hossain, Mohammad B.; Ji, Ping; Anish, Ramakrishnan; Jacobson, Raymond H.; Takada, Shinako

2009-01-01

254

Playing It Safe: Risk Management for Games Play.  

ERIC Educational Resources Information Center

|Considering the players, the game, and the environment in which games are played can make games play at camp safer, more successful, and more enjoyable. Presents factors concerning the players, the game, roughhousing, excessive competitiveness, the environment, space, boundaries, weather, time, and overall game objectives that need to be…

Halliday, Nancy

1996-01-01

255

Disruption of Smad7 Promotes ANG II-Mediated Renal Inflammation and Fibrosis via Sp1-TGF-?/Smad3-NF.?B-Dependent Mechanisms in Mice  

PubMed Central

Smad7 is an inhibitory Smad and plays a protective role in obstructive and diabetic kidney disease. However, the role and mechanisms of Smad7 in hypertensive nephropathy remains unexplored. Thus, the aim of this study was to investigate the role and regulatory mechanisms of Smad7 in ANG II-induced hypertensive nephropathy. Smad7 gene knockout (KO) and wild-type (WT) mice received a subcutaneous infusion of ANG II or control saline for 4 weeks via osmotic mini-pumps. ANG II infusion produced equivalent hypertension in Smad7 KO and WT mice; however, Smad7 KO mice exhibited more severe renal functional injury as shown by increased proteinuria and reduced renal function (both p<0.05) when compared with Smad7 WT mice. Enhanced renal injury in Smad7 KO mice was associated with more progressive renal fibrosis with elevated TGF-?/Smad3 signalling. Smad7 KO mice also showed more profound renal inflammation including increased macrophage infiltration, enhanced IL-1? and TNF-? expression, and a marked activation of NF-?B signaling (all p<0.01). Further studies revealed that enhanced ANG II-mediated renal inflammation and fibrosis in Smad7 KO mice were also associated with up-regulation of Sp1 but downregulation of miR-29b expression. Taken together, the present study revealed that enhanced Sp1-TGF-?1/Smad3-NF-?B signaling and loss of miR-29 may be mechanisms by which deletion of Smad7 promotes ANG II-mediated renal fibrosis and inflammation. Thus, Smad7 may play a protective role in ANG II-induced hypertensive kidney disease.

Huang, Xiao R.; Wei, Lihua; Chen, Hai-Yong; Shi, Yong-Jun; Heuchel, Rainer L.; Lan, Hui Y.

2013-01-01

256

Basal expression of the human MAPEG members microsomal glutathione transferase 1 and prostaglandin E synthase genes is mediated by Sp1 and Sp3.  

PubMed

Microsomal glutathione transferase (MGST1) and prostaglandin E synthase (PGES) are both members of the MAPEG (Membrane Associated Proteins involved in Eicosanoid and Glutathione metabolism) superfamily. In humans, their organ distribution is quite distinct with the former being widely and constitutively expressed whereas PGES is largely inducible. In order to study the basal expression of these genes, we characterized the promoter regions and identified the elements and the transcription factors required using in vitro assays, including reporter analysis of deletion and mutant clones and EMSA. The results indicate that Sp1 is the protein mediating the basal transcription of MGST1. It appears that both the Sp1 and Sp3 proteins are important for the basal expression of PGES. In addition, mutational analysis of two Barbie-box elements in the PGES promoter showed that these were not involved in the down-regulation of PGES by phenobarbital (PB). These results provide the first description of the basal regulation of these genes in humans. PMID:12818425

Ekström, Lena; Lyrenäs, Louise; Jakobsson, Per-Johan; Morgenstern, Ralf; Kelner, Michael J

2003-06-19

257

Sp1 polymorphism in collagen I ?1 gene is associated with osteoporosis in lumbar spine of Mexican women.  

PubMed

The Sp1 binding site polymorphism in collagen type I alpha 1 gene (COLIA1) has been associated with osteoporosis (OP) and bone mineral density (BMD). The aim of this study was to explore the association of this polymorphism with OP and BMD in the Mexican population by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) procedure. Allelic and genotypic frequencies from the Sp1 polymorphism were determined in 100 women with OP, 100 women without OP and 500 subjects from general Mexican population (GMP). Distribution of Sp1 polymorphism was in Hardy-Weinberg equilibrium. In spite of population structure due to racial mix in Mexican population, associations with OP were demonstrated. The frequency of "s" allele was significantly higher in women with OP (35%) than in women without OP (11%; P < 0.00001). Interestingly, "ss" genotype, was exclusive of women with OP and was associated with low BMD (0.588 ± 0.077 g/cm(2)) in contrast to "SS" genotype (0.733 ± 0.039 g/cm(2); P = 0.0001). This work confirms the association of Sp1 polymorphism with low BMD and OP in Mexican population and make sure to use Sp1 as a genetic marker for OP in our population. PMID:20146006

Falcón-Ramírez, Edith; Casas-Avila, Leonora; Miranda, Antonio; Diez, Pilar; Castro, Clementina; Rubio, Julieta; Gómez, Rocío; Valdés-Flores, Margarita

2010-02-10

258

Histone deacetylase inhibitors stimulate mitochondrial HMG-CoA synthase gene expression via a promoter proximal Sp1 site  

PubMed Central

The expression of mitochondrial HMG-CoA synthase in the colon has been correlated with the levels of butyrate present in this tissue. We report here that the effect of butyrate on mitochondrial HMG-CoA synthase gene expression is exerted in vivo at the transcriptional level, and that trichostatin A (TSA), a specific histone deacetylase inhibitor, also induces transcriptional activity and mRNA expression of the gene in human cell lines derived from colon carcinoma. Using chromatin immunoprecipitation assays, we show that histone deacetylase 1 (HDAC1) is associated with the endogenous mitochondrial HMG-CoA synthase promoter and that TSA induction correlates with hyperacetylation of H4 histone associated with the 5? flanking region of the gene. Overexpression of HDAC1 activity leads consistently to mitochondrial HMG-CoA synthase promoter hypoacetylation and reduces its transcriptional activity. The effect of butyrate and TSA maps to a single Sp1 site present in the proximal promoter of the gene, which is able to bind Sp1 and Sp3 proteins. Interestingly, the binding affinity of Sp1 and Sp3 proteins to the Sp1 site correlates with the TSA responsiveness of the promoter. Using a one-hybrid system (GAL4-Sp1 and GAL4-Sp3), we show that both proteins can mediate responsiveness to TSA in CaCo-2 cells employing distinct mechanisms.

Camarero, Nuria; Nadal, Alicia; Barrero, Maria Jose; Haro, Diego; Marrero, Pedro F.

2003-01-01

259

Isolation and partial characterization of ?SP-1, a Salmonella specific lytic phage from intestinal content of broiler chicken.  

PubMed

Salmonella enterica subsp. enterica serovar Enteritidis is a major causative agent of gastroenteritis with contaminated eggs and chicken meat being the major source of infection. Phages are seriously being considered as a safe and cheaper alternative to antibiotics. The intestinal content of chicken was used as source for isolating phages. Phage designated as ?SP-1 was selected for the study. Transmission electron microscopy (TEM) of phage ?SP-1 revealed that it belonged to family Podoviridae. The optimal multiplicity of infection (MOI) was 5 phages/cell. Latent and rise period were calculated to be 30 and 55 minutes respectively, while burst size was 44 phages/bacterial cell. The genome size of ?SP-1 was estimated to be 86?kb from pulsed-field gel electrophoresis analysis (PFGE). The effect of different physical and chemical parameters like temperature, pH, salinity and CaCl? were analyzed to optimize the conditions for large scale production of phages and to check the viability of ?SP-1 under different physiochemical conditions. A temperature of 40?°C, pH 8 and 0.25?M NaCl were found to be optimum for phage adsorption and it was able to survive up to a temperature of 50?°C for 3?min. Capability to survive under hostile environmental conditions, absence of virulence genes in genome and genus specificity suggest suitability of ?SP-1 to be used as a biocontrol agent. PMID:22733367

Augustine, Jeena; Louis, Linda; Varghese, Siju M; Bhat, Sarita G; Kishore, Archana

2012-06-26

260

The Extracytoplasmic Function Sigma Factor SigV Plays a Key Role in the Original Model of Lysozyme Resistance and Virulence of Enterococcus faecalis  

PubMed Central

Background Enterococcus faecalis is one of the leading agents of nosocomial infections. To cause diseases, pathogens or opportunistic bacteria have to adapt and survive to the defense systems encountered in the host. One of the most important compounds of the host innate defense response against invading microorganisms is lysozyme. It is found in a wide variety of body fluids, as well as in cells of the innate immune system. Lysozyme could act either as a muramidase and/or as a cationic antimicrobial peptide. Like Staphylococcus aureus, E. faecalis is one of the few bacteria that are completely lysozyme resistant. Results This study revealed that oatA (O-acetyl transferase) and dlt (D-Alanylation of lipoteicoic acids) genes contribute only partly to the lysozyme resistance of E. faecalis and that a specific transcriptional regulator, the extracytoplasmic function SigV sigma factor plays a key role in this event. Indeed, the sigV single mutant is as sensitive as the oatA/dltA double mutant, and the sigV/oatA/dltA triple mutant displays the highest level of lysozyme sensitivity suggesting synergistic effects of these genes. In S. aureus, mutation of both oatA and dlt genes abolishes completely the lysozyme resistance, whereas this is not the case in E. faecalis. Interestingly SigV does not control neither oatA nor dlt genes. Moreover, the sigV mutants clearly showed a reduced capacity to colonize host tissues, as they are significantly less recovered than the parental JH2-2 strain from organs of mice subjected to intravenous or urinary tract infections. Conclusions This work led to the discovery of an original model of lysozyme resistance mechanism which is obviously more complex than those described for other Gram positive pathogens. Moreover, our data provide evidences for a direct link between lysozyme resistance and virulence of E. faecalis.

Le Jeune, Andre; Torelli, Riccardo; Sanguinetti, Maurizio; Giard, Jean-Christophe; Hartke, Axel; Auffray, Yanick; Benachour, Abdellah

2010-01-01

261

The transcriptional repressor ZBP-89 and the lack of Sp1/Sp3, c-Jun, and Stat3 are important for the down-regulation of the vimentin gene during C2C12 myogenesis  

PubMed Central

Currently, considerable information is available about how muscle-specific genes are activated during myogenesis, yet little is known about how non-muscle genes are down-regulated. The intermediate filament protein vimentin is known to be “turned off” during myogenesis to be replaced by desmin, the muscle-specific intermediate filament protein. Here, we demonstrate that vimentin down-regulation is the result of the combined effect of several transcription factors. Levels of the positive activators, Sp1/Sp3, which are essential for vimentin expression, decrease during myogenesis. In addition, c-Jun and Stat3, two additional positive-acting transcription factors for vimentin gene expression, are also down-regulated. Over-expression via adenoviral approaches demonstrates that the up-regulation of the repressor ZBP-89 is critical to vimentin down-regulation. Elimination of ZBP-89 via siRNA blocks the down-regulation of vimentin and Sp1/Sp3 expression. From these studies we conclude that the combinatorial effect of the down-regulation of positive-acting transcription factors such as Sp1/Sp3, c-Jun and Stat3 versus the up-regulation of the repressor ZBP-89 contributes to the “turning off” of the vimentin gene during myogenesis.

Salmon, Morgan; Zehner, Zendra E.

2009-01-01

262

Play Therapy: A Review  

ERIC Educational Resources Information Center

|This article discusses the current issues in play therapy and its implications for play therapists. A brief history of play therapy is provided along with the current play therapy approaches and techniques. This article also touches on current issues or problems that play therapists may face, such as interpreting children's play, implementing…

Porter, Maggie L.; Hernandez-Reif, Maria; Jessee, Peggy

2009-01-01

263

Characteristics of risky play  

Microsoft Academic Search

This paper explores what makes children's risky play risky. Risky play can generally be defined as thrilling and exciting forms of play that involve a risk of physical injury. Few, if any, studies have been conducted to explore what identifies play activity as risky. The present study aims to determine what characteristics to judge risky play by. Risky play in

Ellen Beate Hansen Sandseter

2009-01-01

264

A Content Analysis of Interviews with Players of Massively Multiplayer Online Role-Play Games (MMORPGs): Motivating Factors and the Impact on Relationships  

Microsoft Academic Search

This paper explores the intrapersonal and interpersonal motivations involved in the playing of MMORPGs, and the impacts of\\u000a gaming on online and offline relationships. Twenty-one participants completed an online synchronous interview in which they\\u000a discussed their personal experiences of playing MMORPGs. An online survey was then developed to further explore the findings\\u000a of the interviews and this was completed by

Jacqui Taylor; James Taylor

2009-01-01

265

Children's Play and Television.  

ERIC Educational Resources Information Center

|Discusses adverse effects of FCC deregulation of children's television programming on children's play behavior. Discusses the difference between play and imitation, the role of high quality dramatic play in healthy child development, the popularity of war play, and use of toys to increase dramatic play. Considers ways to help children gain…

Powell, Mark

2001-01-01

266

Coregulator small nuclear RING finger protein (SNURF) enhances Sp1- and steroid receptor-mediated transcription by different mechanisms.  

PubMed

The small nuclear RING finger protein SNURF is not only a coactivator in steroid receptor-dependent transcription but also activates transcription from steroid-independent promoters. In this work, we show that SNURF, via the RING finger domain, enhances protein binding to Sp1 elements/GC boxes and interacts and cooperates with Sp1 in transcriptional activation. The activation of androgen receptor (AR) function requires regions other than the RING finger of SNURF, and SNURF does not influence binding of AR to cognate DNA elements. The zinc finger region (ZFR) together with the hinge region of AR are sufficient for contacting SNURF. The nuclear localization signal in the boundary between ZFR and the hinge region participates in the association of AR with SNURF, and a receptor mutant lacking the C-terminal part of the bipartite nuclear localization signal shows attenuated response to coexpressed SNURF. Some AR ZFR point mutations observed in patients with partial androgen insensitivity syndrome or male breast cancer impair the interaction of AR with SNURF and also render AR refractory to the transcription-activating effect of SNURF. Collectively, SNURF modulates the transcriptional activities of androgen receptor and Sp1 via different domains, and it may act as a functional link between steroid- and Sp1-regulated transcription. PMID:10617653

Poukka, H; Aarnisalo, P; Santti, H; Jänne, O A; Palvimo, J J

2000-01-01

267

Interaction between Sp1 and Cell Cycle Regulatory Proteins Is Important in Transactivation of a Differentiation-related Gene1  

Microsoft Academic Search

The stratified squamous epithelium is a model system in which to define molecular mechanisms underlying the switch from proliferation to differ- entiation. This can be achieved through the functional dissection of ker- atin gene promoters. Having previously established the importance of keratin 4 in maintaining the differentiated phenotype in corneal epithelial cells, we investigated the role of Sp1-mediated transactivation of

Oliver G. Opitz; Anil K. Rustgi

268

Ethanol induces cell cycle arrest and triggers apoptosis via Sp1-dependent p75NTR expression in human neuroblastoma cells.  

PubMed

Ethanol exposure has deleterious effects on the central nervous system. Although several mechanisms for ethanol-induced damage have been suggested, the precise mechanism underlying ethanol-induced neuronal cell death remains unclear. Recent studies indicate that the p75 neurotrophin receptor (p75NTR) has a critical role in the regulation of neuronal survival. This study was designed to examine the role of p75NTR in ethanol-induced apoptotic signaling in neuroblastoma cells. Ethanol caused highly increased level of p75NTR expression. The use of small interfering RNA to inhibit p75NTR expression markedly attenuated ethanol-induced cell cycle arrest and apoptosis. DNA binding activity of Sp1 was increased by ethanol, whereas inhibition of Sp1 activity by mithramycin, a Sp1 inhibitor, or short hairpin RNA suppressed ethanol-induced p75NTR expression. In addition, inhibitors of casein kinase 2 (CK2) and extracellular signal-regulated kinase (ERK) augmented ethanol-induced p75NTR expression. Our results also demonstrate that inhibition of ERK and CK2 caused a further increase in the activation of the p75NTR proximal promoter induced by ethanol. This increased activation was partially suppressed by the deletion of the Sp1 binding sites. These results suggest that Sp1-mediated p75NTR expression is regulated at least in part by ERK and CK2 pathways. The present study also showed that treatment with ethanol resulted in significant increases in the expression of p21, but not the levels of p53 and p53 target genes such as Bax, Puma, and Bcl-2. Furthermore, the inhibition of p75NTR expression or Sp1 activity suppressed ethanol-induced p21 expression, cell cycle arrest, and apoptosis. These data suggest that ethanol increases p75NTR expression, and CK2 and ERK signaling inversely regulate Sp1-mediated p75NTR expression in ethanol-treated neuroblastoma cells. Thus, our study provides more insight into the mechanisms underlying ethanol actions. PMID:24026251

Do, Hang; Park, Hey-Jin; Sohn, Eun-Hwa; Kim, Byung-Oh; Um, Sung Hee; Kwak, Jong-Hwan; Moon, Eun-Yi; Rhee, Dong-Kwon; Pyo, Suhkneung

2013-09-12

269

Activation of TGF-?1 promoter by hepatitis C virus-induced AP-1 and Sp1: role of TGF-?1 in hepatic stellate cell activation and invasion.  

PubMed

Our previous studies have shown the induction and maturation of transforming growth factor-beta 1 (TGF-?1) in HCV-infected human hepatoma cells. In this study, we have investigated the molecular mechanism of TGF-?1 gene expression in response to HCV infection. We demonstrate that HCV-induced transcription factors AP-1, Sp1, NF-?B and STAT-3 are involved in TGF-?1 gene expression. Using chromatin immunoprecipitation (ChIP) assay, we further show that AP-1 and Sp1 interact with TGF-b1 promoter in vivo in HCV-infected cells. In addition, we demonstrate that HCV-induced TGF-?1 gene expression is mediated by the activation of cellular kinases such as p38 MAPK, Src, JNK, and MEK1/2. Next, we determined the role of secreted bioactive TGF-?1 in human hepatic stellate cells (HSCs) activation and invasion. Using siRNA approach, we show that HCV-induced bioactive TGF-?1 is critical for the induction of alpha smooth muscle actin (?-SMA) and type 1 collagen, the markers of HSCs activation and proliferation. We further demonstrate the potential role of HCV-induced bioactive TGF-?1 in HSCs invasion/cell migration using a transwell Boyden chamber. Our results also suggest the role of HCV-induced TGF-?1 in HCV replication and release. Collectively, these observations provide insight into the mechanism of TGF-?1 promoter activation, as well as HSCs activation and invasion, which likely manifests in liver fibrosis associated with HCV infection. PMID:23437118

Presser, Lance D; McRae, Steven; Waris, Gulam

2013-02-21

270

Activation of TGF-?1 Promoter by Hepatitis C Virus-Induced AP-1 and Sp1: Role of TGF-?1 in Hepatic Stellate Cell Activation and Invasion  

PubMed Central

Our previous studies have shown the induction and maturation of transforming growth factor-beta 1 (TGF-?1) in HCV-infected human hepatoma cells. In this study, we have investigated the molecular mechanism of TGF-?1 gene expression in response to HCV infection. We demonstrate that HCV-induced transcription factors AP-1, Sp1, NF-?B and STAT-3 are involved in TGF-?1 gene expression. Using chromatin immunoprecipitation (ChIP) assay, we further show that AP-1 and Sp1 interact with TGF-b1 promoter in vivo in HCV-infected cells. In addition, we demonstrate that HCV-induced TGF-?1 gene expression is mediated by the activation of cellular kinases such as p38 MAPK, Src, JNK, and MEK1/2. Next, we determined the role of secreted bioactive TGF-?1 in human hepatic stellate cells (HSCs) activation and invasion. Using siRNA approach, we show that HCV-induced bioactive TGF-?1 is critical for the induction of alpha smooth muscle actin (?-SMA) and type 1 collagen, the markers of HSCs activation and proliferation. We further demonstrate the potential role of HCV-induced bioactive TGF-?1 in HSCs invasion/cell migration using a transwell Boyden chamber. Our results also suggest the role of HCV-induced TGF-?1 in HCV replication and release. Collectively, these observations provide insight into the mechanism of TGF-?1 promoter activation, as well as HSCs activation and invasion, which likely manifests in liver fibrosis associated with HCV infection.

Presser, Lance D.; McRae, Steven; Waris, Gulam

2013-01-01

271

Characterization of human collagen XVIII promoter 2: interaction of Sp1, Sp3 and YY1 with the regulatory region and a SNP that increases transcription in hepatocytes.  

PubMed

Different levels of Collagen XVIII expression have been associated with several pathological processes such as cancer, liver fibrosis, diabetic retinopathy and Alzheimer's disease. Understanding the transcriptional regulation of Collagen XVIII might elucidate some pathways related to the progression of these diseases. The promoter 2 of COL18A1 gene is poorly understood and is responsible for the transcription of this gene in several adult tissues such as liver, eyes and brain. This study focused upon characterization of cis-regulatory elements interacting with human COL18A1 promoter 2 and identification of SNPs in this region in different ethnic groups. Our results show that there are five conserved regions (I to V) between human and mouse promoter 2 and that the human COL18A1 core promoter is located between nucleotides -186 and -21. Sp1 and Sp3 bind to conserved regions I and V, while Sp3 and YY1 interact with region II. We have verified that the SNP at position -700 (T>G) is embedded in two common haplotypes, which have different frequencies between European and African descendents. The allele -700G increases transcription and binding for a still unknown transcription factor. SNP -700 affects Sp3 and YY1 interaction with this region, even though it is not part of these transcription factors' predicted binding sites. Therefore, our results show for the first time that Sp3 and YY1 interact with human COL18A1 promoter 2, and that nucleotide -700 is part of a binding motif for a still unknown TF that is involved in the expression of this gene in hepatocytes. In addition, we also confirm the involvement of Sp1 in the regulation of this gene. PMID:16229994

Armelin-Correa, Lucia M; Lin, Chin J; Barbosa, Angela; Bagatini, Kelly; Winnischofer, Sheila M B; Sogayar, Mari C; Passos-Bueno, Maria Rita

2005-10-17

272

Economic-Statistical Design of Effective Variance Control Charts, /Sp/1/p  

NASA Astrophysics Data System (ADS)

Multivariate Statistical Process Control (MSPC) is to control several quality characteristics simultaneously during a production process. When a process is statistically under control, only common causes of variability affect the process. The MSPC techniques help to detect the special causes of variability on the process. In the last few years multivariate quality control has been thoroughly studied and there are different but those charts don't let control de multivariate dispersion on process. Recently the generalized variance control chart /S/, has been develop to control multivariate dispersion. Nevertheless, this chart is unhelpful to work with incomplete databases or with missing data, that are commonly found in a great deal of processes due to the failure of certain sensors. In this sense, Garcia-Diaz developed the effective variance control chart, /Sp/1/p, to control multivariate dispersion with missing data. To design the economic-statistical of the Variance Effective control chart, attempting to obtain the values of the parameters in the sampling plan that minimize the expected operation costs by time unit, according to the restrictions of a minimum ARL value under control, and a maximum ARL value when the process is out of control.

García-Díaz, J. Carlos; Martínez-Gómez, M.

2009-11-01

273

The Play of Psychotherapy  

ERIC Educational Resources Information Center

|The author reviews the role of play within psychotherapy. She does not discuss the formal play therapy especially popular for young children, nor play from the Jungian perspective that encourages the use of the sand tray with adults. Instead, she focuses on the informal use of play during psychotherapy as it is orchestrated intuitively. Because…

Marks-Tarlow, Terry

2012-01-01

274

Musical Instrument Choice and Playing History in Post-Secondary Level Music Students: Some Descriptive Data, Some Causes and Some Background Factors  

ERIC Educational Resources Information Center

|Why do musicians specialize in the specific instruments that they do? Research has shown effects of such factors as the perceived masculinity/femininity of instruments and musician's personality but there are little background data on other factors. The present study had two major aims. The first aim was to gather some useful background data on…

Chen, Simy Meng-Yu; Howard, Robert W.

2004-01-01

275

CD1d induction in solid tumor cells by histone deacetylase inhibitors through inhibition of HDAC1/2 and activation of Sp1  

PubMed Central

CD1d is a MHC class-like molecule that presents glycolipids to natural killer T (NKT) cells, then regulates innate and adaptive immunity. The regulation of CD1d gene expression in solid tumors is still largely unknown. Gene expression can be epigenetically regulated by DNA methylation and histone acetylation. We found that histone deacetylase inhibitors, trichostatin A (TSA) and suberoylanilide hydroxamic acid (SAHA), induced CD1d gene expression in human (A549 and NCI-H292) and mouse (TC-1 and B16/F0) cancer cells. Simultaneous knockdown of HDAC1 and 2 induced CD1d gene expression. Sp1 inhibitor mitramycin A (MTM) blocked TSA- and SAHA-induced CD1d mRNA expression and Sp1 luciferase activity. Co-transfection of GAL4-Sp1 and Fc-luciferase reporters demonstrated that TSA and SAHA induced Sp1 luciferase reporter activity by enhancing Sp1 transactivation activity. The binding of Sp1 to CD1d promoter and histone H3 acetylation on Sp1 sites were increased by TSA and SAHA. These results indicate that TSA and SAHA could up-regulate CD1d expression in tumor cells through inhibition of HDAC1/2 and activation of Sp1.

Yang, Pei-Ming; Lin, Pei-Jie; Chen, Ching-Chow

2012-01-01

276

A Single-Base Substitution in the Proximal Sp1 Site of the Human Low Density Lipoprotein Receptor Promoter as a Cause of Heterozygous Familial Hypercholesterolemia  

Microsoft Academic Search

We have identified a Finnish family with a typical phenotype of heterozygous familial hypercholesterolemia (FH) due to a single-base substitution in the proximal Sp1 binding site of the low density lipoprotein (LDL) receptor gene promoter. The mutation, a C --> T substitution at nucleotide -43, cosegregated with the FH phenotype in six available family members and abolished binding of Sp1

Ulla-Maija Koivisto; Jorma J. Palvimo; Olli A. Janne; Kimmo Kontula

1994-01-01

277

Examining Resource and Protective Factors in the Adjustment of Latino Youth in Low Income Families: What Role Does Maternal Acculturation Play?  

Microsoft Academic Search

This longitudinal study examined whether the risk and positive factors contributing to the delinquent behaviors and internalizing\\u000a problems of 454 Latino adolescents varied across maternal linguistic acculturation and adolescent gender. Although the level\\u000a of cumulative risk to which the 10-to-14-year old adolescents were exposed did not vary by maternal linguistic acculturation,\\u000a the factors contributing to their subsequent adjustment 16 months

Alexandra Loukas; Marie-Anne Suizzo; Hazel M. Prelow

2007-01-01

278

Specificity protein, Sp1-mediated increased expression of Prdx6 as a curcumin-induced antioxidant defense in lens epithelial cells against oxidative stress  

PubMed Central

Peroxiredoxin 6 (Prdx6) is a pleiotropic oxidative stress-response protein that defends cells against reactive oxygen species (ROS)-induced damage. Curcumin, a naturally occurring agent, has diversified beneficial roles including cytoprotection. Using human lens epithelial cells (hLECs) and Prdx6-deficient cells, we show the evidence that curcumin protects cells by upregulating Prdx6 transcription via invoking specificity protein 1 (Sp1) activity against proapoptotic stimuli. Curcumin enhanced Sp1 and Prdx6 mRNA and protein expression in a concentration-dependent manner, as evidenced by western and real-time PCR analyses, and thereby negatively regulated ROS-mediated apoptosis by blunting ROS expression and lipid peroxidation. Bioinformatic analysis and DNA–protein binding assays disclosed three active Sp1 sites (?19/27, ?61/69 and ?82/89) in Prdx6 promoter. Co-transfection experiments with Sp1 and Prdx6 promoter–chloramphenicol acetyltransferase (CAT) constructs showed that CAT activity was dramatically increased in LECs or Sp1-deficient cells (SL2). Curcumin treatment of LECs enhanced Sp1 binding to its sites, consistent with curcumin-dependent stimulation of Prdx6 promoter with Sp1 sites and cytoprotection. Notably, disruption of Sp1 sites by point mutagenesis abolished curcumin transactivation of Prdx6. Also, curcumin failed to activate Prdx6 expression in the presence of Sp1 inhibitors, demonstrating that curcumin-mediated increased expression of Prdx6 was dependent on Sp1 activity. Collectively, the study may provide a foundation for developing transcription-based inductive therapy to reinforce endogenous antioxidant defense by using dietary supplements.

Chhunchha, B; Fatma, N; Bhargavan, B; Kubo, E; Kumar, A; Singh, D P

2011-01-01

279

Play the Electrocardiogram Game  

MedlinePLUS

... and Work Teachers' Questionnaire Electrocardiogram Play the ECG Game About the game ECG is used for diagnosing heart conditions by ... last will in Paris. Play the Blood Typing Game Try to save some patients and learn about ...

280

Apolipoprotein E4 Is Deficient in Inducing Macrophage ABCA1 Expression and Stimulating the Sp1 Signaling Pathway  

PubMed Central

ATP binding cassette A1 (ABCA1) is a membrane protein that promotes cellular cholesterol efflux. Using RAW 264.7 macrophages, we studied the relative effects of apolipoprotein (apo) E3 and apoE4 on ABCA1 and on the signaling pathway that regulates its expression. Both lipid-associated and lipid-free apoE4 forms induced ?30% lower levels of ABCA1 protein and mRNA than apoE3 forms. Phosphorylated levels of phosphoinositol 3-kinase (PI3K), protein kinase C? (PKC?) and specificity protein 1 (Sp1) were also lower when treated with apoE4 compared to apoE3. The reduced ability of apoE4 to induce ABCA1 expression, PKC? and Sp1 phosphorylation were confirmed in human THP-1 monocytes/macrophages. Sequential phosphorylation of PI3K, PKC? and Sp1 has been suggested as a mechanism for upregulation of ABCA1 expression. Both apoE3 and apoE4 reduced total cholesterol and cholesterol esters in lipid-laden RAW 264.7 cells, and induced apoAI-mediated cholesterol efflux. However, the cholesterol esters and cholesterol efflux in apoE4-treated cells were ?50% and ?24% lower, respectively, compared to apoE3-treated cells. Accumulation of cholesterol esters in macrophages is a mechanism for foam cell formation. Thus the reduced ability of apoE4 to activate the PI3K-PKC?-Sp1 signaling pathway and induce ABCA1 expression likely impairs cholesterol ester removal, and increases foam cell formation.

Okoro, Emmanuel Ugochukwu; Zhao, Yanfeng; Guo, ZhongMao; Zhou, Lichun; Lin, Xinghua; Yang, Hong

2012-01-01

281

Sp1 modulates ncOGT activity to alter target recognition and enhanced thermotolerance in E. coli  

Microsoft Academic Search

cDNAs encoding three isoforms of OGT (ncOGT, mOGT, and sOGT) were expressed in Escherichia coli in which the coexpression system of OGT with target substrates was established in vivo. No endogenous bacterial proteins were significantly O-GlcNAcylated by any type of OGT isoform while co-expressed p62 and Sp1 were strongly O-GlcNAcylated by ncOGT. These results suggest that most of bacterial proteins

In-Hyun Riu; Il-Soo Shin; Su-Il Do

2008-01-01

282

The Excellence of Play.  

ERIC Educational Resources Information Center

|Recognizing that for young children, play is a tool for learning, this book compiles contributions by different authors, reflecting both up-to-date research and current classroom practice as they relate to children's play. Part 1 of the book explores the value of play as a cross-cultural concept as well as one rooted in the Western world. Gender…

Moyles, Janet R., Ed.

283

Designing for playful photography  

Microsoft Academic Search

This paper highlights the concept of playful photography as an emerging and important area for Human Computer Interaction (HCI) research, through bringing together three research projects investigating new ways of engaging with digital photography with theories related to playfulness and experience-centred design. Drawing upon this, we start to unpack playful photography and its characteristics. Instead of aiming for a unifying

Marianne Graves Petersen; Sara Ljungblad; Maria Håkansson

2009-01-01

284

The Excellence of Play.  

ERIC Educational Resources Information Center

Recognizing that for young children, play is a tool for learning, this book compiles contributions by different authors, reflecting both up-to-date research and current classroom practice as they relate to children's play. Part 1 of the book explores the value of play as a cross-cultural concept as well as one rooted in the Western world. Gender…

Moyles, Janet R., Ed.

285

The Pedagogy of Play  

ERIC Educational Resources Information Center

|Play is important. Environmental educators Sobel and Louv write about the relationship between children and outside play and suggest that early transcendental experiences within nature allow children to develop empathetic orientations towards the natural world. Children who play out-of-doors develop an appreciation for the environment and…

Giesbrecht, Sheila

2012-01-01

286

The Identification of Play.  

ERIC Educational Resources Information Center

Several approaches to the study of play are examined and critiqued, including Matthews and Matthews' (1982) paradigm case approach and Sutton-Smith and Kelly-Byrne's (1984) view of play as a commonly-recognized-as-framed event in which the metacommunicative function always retains primacy. Consideration of the genesis of play in the child leads to…

Cornwell, David; Hobbs, Sandy

287

Pedagogy of Play  

Microsoft Academic Search

“Pedagogy of play” focuses on the educational value of this field of experience, by claiming that play characterizes the two fundamental guidelines which are at the basis of education; the spontaneous and natural direction on the one side, and the intentional one on the other side. It is commonly assumed that pedagogy of play concerns only the latter of the

Roberto Farné

2005-01-01

288

Play Is the Way  

ERIC Educational Resources Information Center

|Historically, play has been viewed as a frivolous break from important endeavors like working and learning when, in fact, a child's ability to fully and freely engage in play is essential to their learning, productivity, and overall development. A natural drive to play is universal across all young mammals. Children from every society on earth…

Gross, Steve; Sanderson, Rebecca Cornelli

2012-01-01

289

What about a Play?  

ERIC Educational Resources Information Center

Reading and writing plays can be a good way to learn reading, listening, and writing skills. This paper contains suggestions for using plays in adult literacy courses. Ideas are given for reading and writing plays, including developing a plot and characters, drafting a script, and editing and finalizing a script. Various methods of transcribing…

Eggar, Rosey

290

Kupffer cells play an important role in the cytokine production and activation of nuclear factors of liver grafts from non-heart-beating donors  

Microsoft Academic Search

In the non-heart-beating donor (NHBD) deterioration of microcirculation of the liver graft is strongly associated with secretion of cytokines and eicosanoids. In this study we investigated the excretion of cytokines, eicosanoids, and DNA binding activity of transcription factors in the grafts from NHBD and evaluated the effects of the elimination of Kupffer cells on them. The purpose of this study

Kosei Oikawa; Nobuhiro Ohkohchi; Masahide Sato; Atsuschi Masamume; Susumu Satomi

2002-01-01

291

Examining Resource and Protective Factors in the Adjustment of Latino Youth in Low Income Families: What Role Does Maternal Acculturation Play?  

ERIC Educational Resources Information Center

|This longitudinal study examined whether the risk and positive factors contributing to the delinquent behaviors and internalizing problems of 454 Latino adolescents varied across maternal linguistic acculturation and adolescent gender. Although the level of cumulative risk to which the 10-to-14-year old adolescents were exposed did not vary by…

Loukas, Alexandra; Suizzo, Marie-Anne; Prelow, Hazel M.

2007-01-01

292

Examining Resource and Protective Factors in the Adjustment of Latino Youth in Low Income Families: What Role Does Maternal Acculturation Play?  

ERIC Educational Resources Information Center

This longitudinal study examined whether the risk and positive factors contributing to the delinquent behaviors and internalizing problems of 454 Latino adolescents varied across maternal linguistic acculturation and adolescent gender. Although the level of cumulative risk to which the 10-to-14-year old adolescents were exposed did not vary by…

Loukas, Alexandra; Suizzo, Marie-Anne; Prelow, Hazel M.

2007-01-01

293

A naturally occurring deletion in the SRY promoter region affecting the Sp1 binding site is associated with sex reversal.  

PubMed

Male to female sex reversal results from failure of testis development. Mutations in the SRY gene or in other genes involved in the sexual differentiation pathway are considered to cause XY gonadal dysgenesis. The majority of the mutations in the SRY described so far are located within the SRY coding region, mainly in the HMG-box conserved domain. Comparison of 5' flanking SRY gene sequences among different species indicated the presence of several putative conserved consensus sequences for different transcription regulators. In this study, we investigated a 360 bp sequence encompassing the SRY putative core promoter, in 17 patients with variable degrees of 46,XY sex reversal, which have been previously shown not to bear mutations in the SRYcoding region. Sequencing analysis of the SRYpromoter in one patient with complete XY gonadal dysgenesis revealed a three base pair deletion in one of the Sp1 binding sites. The deletion abolished Sp1 binding in vitro. This is the first report on a naturally occurring mutation affecting the Sp1 regulatory element in the SRY promoter region, which is associated with sex reversal. Additionally, upon familial investigation the father, who had 18 genital surgeries due to severe hypospadia without cryptorchidism, was found to bear the same deletion and several relatives were referred to have sexual ambiguity. PMID:16218050

Assumpção, J G; Ferraz, L F Caldas; Benedetti, C E; Maciel-Guerra, A T; Guerra, G; Marques-de-Faria, A P; Baptista, M T Matias; de Mello, M P

294

Inter-Play  

NSDL National Science Digital Library

Inter-Play is a Web-based, multilingual index to plays published as part of collections, anthologies, or periodicals, and compiles many citations to plays not indexed by standard print indexes. Inter-Play contains about 16,130 bibliographic citations and spans in date from the late nineteenth century to the present. Although the index is multilingual, the search interface is in English. Users may search the index by author or title only. Inter-Play is updated frequently by its co-editors: Robert Westover and Janet Wright, humanities librarians at Portland State University.

295

Caloric Cost of Playing Golf  

ERIC Educational Resources Information Center

Women who play golf at the same rate of speed as men will use energy at a higher rate, but the rapidity with which the course is completed, which is dependent on the number of members of the golfing party, is a factor in the caloric expenditure of both sexes. (JD)

Lampley, James H.; And Others

1977-01-01

296

NELL-1, an osteoinductive factor, is a direct transcriptional target of Osterix.  

PubMed

NELL-1 is a novel secreted protein associated with premature fusion of cranial sutures in craniosynostosis that has been found to promote osteoblast cell differentiation and mineralization. Our previous study showed that Runx2, the key transcription factor in osteoblast differentiation, transactivates the NELL-1 promoter. In this study, we evaluated the regulatory involvement and mechanisms of Osterix, an essential transcription factor of osteoblasts, in NELL-1 gene expression and function. Promoter analysis showed a cluster of potential Sp1 sites (Sp1/Osterix binding sites) within approximately 70 bp (from -71 to -142) of the 5' flanking region of the human NELL-1 transcriptional start site. Luciferase activity in our NELL-1 promoter reporter systems was significantly decreased in Saos-2 cells when Osterix was overexpressed. Mutagenesis study demonstrated that this suppression is mediated by the Sp1 sites. The binding specificity of Osterix to these Sp1 sites was confirmed in Saos-2 cells and primary human osteoblasts by EMSA in vitro and ChIP assay in vivo. ChIP assay also showed that Osterix downregulated NELL-1 by affecting binding of RNA polymerase II to the NELL-1 promoter, but not by competing with Runx2 binding to the OSE2 sites. Moreover, NELL-1 mRNA levels were significantly decreased when Osterix was overexpressed in Saos-2, U2OS, Hela and Glioma cells. Correspondingly, knockdown of Osterix increased NELL-1 transcription and osteoblastic differentiation in both Saos-2 cells and primary human osteoblasts. These results suggest that Osterix is a direct transcriptional regulator with repressive effect on NELL-1 gene expression, contributing to a delicate balance of regulatory effects on NELL-1 transcription with Runx2, and may play a crucial role in osteoblast differentiation and mineralization. These findings also extend our understanding of the molecular mechanism of Runx2, Osterix, and NELL-1 and demonstrate their crosstalk during osteogenesis. PMID:21931789

Chen, Feng; Zhang, Xinli; Sun, Shan; Zara, Janette N; Zou, Xuan; Chiu, Robert; Culiat, Cymbelin T; Ting, Kang; Soo, Chia

2011-09-13

297

The transcription factors Nkx2.2 and Nkx2.9 play a novel role in floor plate development and commissural axon guidance.  

PubMed

The transcription factors Nkx2.2 and Nkx2.9 have been proposed to execute partially overlapping functions in neuronal patterning of the ventral spinal cord in response to graded sonic hedgehog signaling. The present report shows that in mice lacking both Nkx2 proteins, the presumptive progenitor cells in the p3 domain of the neural tube convert to motor neurons (MN) and never acquire the fate of V3 interneurons. This result supports the concept that Nkx2 transcription factors are required to establish V3 progenitor cells by repressing the early MN lineage-specific program, including genes like Olig2. Nkx2.2 and Nkx2.9 proteins also perform an additional, hitherto unknown, function in the development of non-neuronal floor plate cells. Here, we demonstrate that loss of both Nkx2 genes results in an anatomically smaller and functionally impaired floor plate causing severe defects in axonal pathfinding of commissural neurons. Defective floor plates were also seen in Nkx2.2(+/-);Nkx2.9(-/-) compound mutants and even in single Nkx2.9(-/-) mutants, suggesting that floor plate development is sensitive to dose and/or timing of Nkx2 expression. Interestingly, adult Nkx2.2(+/-);Nkx2.9(-/-) compound-mutant mice exhibit abnormal locomotion, including a permanent or intermittent hopping gait. Drug-induced locomotor-like activity in spinal cords of mutant neonates is also affected, demonstrating increased variability of left-right and flexor-extensor coordination. Our data argue that the Nkx2.2 and Nkx2.9 transcription factors contribute crucially to the formation of neuronal networks that function as central pattern generators for locomotor activity in the spinal cord. As both factors affect floor plate development, control of commissural axon trajectories might be the underlying mechanism. PMID:21068056

Holz, Andreas; Kollmus, Heike; Ryge, Jesper; Niederkofler, Vera; Dias, Jose; Ericson, Johan; Stoeckli, Esther T; Kiehn, Ole; Arnold, Hans-Henning

2010-11-10

298

Interleukin-18 induces EMMPRIN expression in primary cardiomyocytes via JNK/Sp1 signaling and MMP-9 in part via EMMPRIN and through AP-1 and NF-?B activation  

PubMed Central

IL-18 and the extracellular matrix metalloproteinase (MMP) inducer (EMMPRIN) stimulate the expression of proinflammatory cytokines and MMPs and are elevated in myocardial hypertrophy, remodeling, and failure. Here, we report several novel findings in primary cardiomyocytes treated with IL-18. First, IL-18 activated multiple transcription factors, including NF-?B (p50 and p65), activator protein (AP)-1 (cFos, cJun, and JunD), GATA, CCAAT/enhancer-binding protein, myocyte-specific enhancer-binding factor, interferon regulatory factor-1, p53, and specific protein (Sp)-1. Second, IL-18 induced EMMPRIN expression via myeloid differentiation primary response gene 88/IL-1 receptor-associated kinase/TNF receptor-associated factor-6/JNK-dependent Sp1 activation. Third, IL-18 induced a number of MMP genes, particularly MMP-9, at a rapid rate as well as tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-3 at a slower rate. Finally, the IL-18 induction of MMP-9 was mediated in part via EMMPRIN and through JNK- and ERK-dependent AP-1 activation and p38 MAPK-dependent NF-?B activation. These results suggest that the elevated expression of IL-18 during myocardial injury and inflammation may favor EMMPRIN and MMP induction and extracellular matrix degradation. Therefore, targeting IL-18 or its signaling pathways may be of potential therapeutic benefit in adverse remodeling.

Reddy, Venkatapuram Seenu; Prabhu, Sumanth D.; Mummidi, Srinivas; Valente, Anthony J.; Venkatesan, Balachandar; Shanmugam, Prakashsrinivasan; Delafontaine, Patrice

2010-01-01

299

Activation of heat shock factor 1 plays a role in pyrrolidine dithiocarbamate-mediated expression of the co-chaperone BAG3  

PubMed Central

Adaptive responses to physical and inflammatory stressors are mediated by transcription factors and molecular chaperones. The transcription factor heat shock factor 1 (HSF1) has been implicated in extending lifespan in part by increasing expression of heat shock response genes. Pyrrolidine dithiocarbamate (PDTC) is a small thiol compound that exerts in vivo and in vitro anti-inflammatory properties through mechanisms that remain unclear. Here we report that PDTC induced the release of monomeric HSF1 from the molecular chaperone heat shock protein 90 (Hsp90), with concomitant increase in HSF1 trimer formation, translocation to the nucleus, and binding to promoter of target genes in human HepG2 cells. siRNA-mediated silencing of HSF1 blocked BAG3 gene expression by PDTC. The protein levels of the co-chaperone BAG3 and its interaction partner Hsp72 were stimulated by PDTC in a dose-dependent fashion, peaking at 6 hours. Inhibition of Hsp90 function by geldanamycin derivatives and novobiocin elicited a pattern of HSF1 activation and BAG3 expression that was similar to PDTC. Chromatin immunoprecipitation studies showed that PDTC and the inhibitor 17-dimethylaminoethylamino-17-demethoxygeldanamycin enhanced the binding of HSF1 to the promoter of several target genes, including BAG3, HSPA1A, HSPA1B, FKBP4, STIP1 and UBB. Cell treatment with PDTC increased significantly the level of Hsp90? thiol oxidation, a posttranslational modification known to inhibit its chaperone function. These results unravel a previously unrecognized mechanism by which PDTC and related compounds could confer cellular protection against inflammation through HSF1-induced expression of heat shock response genes.

Song, Shaoming; Kole, Sutapa; Precht, Patricia; Pazin, Michael J.; Bernier, Michel

2010-01-01

300

Transcriptional profiling of Medicago truncatula under salt stress identified a novel CBF transcription factor MtCBF4 that plays an important role in abiotic stress responses  

Microsoft Academic Search

Background  Salt stress hinders the growth of plants and reduces crop production worldwide. However, different plant species might possess\\u000a different adaptive mechanisms to mitigate salt stress. We conducted a detailed pathway analysis of transcriptional dynamics\\u000a in the roots of Medicago truncatula seedlings under salt stress and selected a transcription factor gene, MtCBF4, for experimental validation.\\u000a \\u000a \\u000a \\u000a \\u000a Results  A microarray experiment was conducted using

Daofeng Li; Yunqin Zhang; Xiaona Hu; Xiaoye Shen; Lei Ma; Zhen Su; Tao Wang; Jiangli Dong

2011-01-01

301

Suppression of the androgen receptor function by quercetin through protein–protein interactions of Sp1, c-Jun, and the androgen receptor in human prostate cancer cells  

Microsoft Academic Search

We have previously reported that the increase in c-Jun expression induced by quercetin inhibited androgen receptor (AR) transactivation,\\u000a and Sp1 was involved in quercetin-mediated downregulation of AR activity. Transient transfection assays in this work revealed\\u000a that co-expression of c-Jun quenched Sp1-induced production of luciferase activity driven by AR promoter or three copies of\\u000a Sp1 binding elements in the AR promoter.

Huiqing YuanCharles; Charles Y. F. Young; Yuanyuan Tian; Zhifang Liu; Mengye Zhang; Hongxiang Lou

2010-01-01

302

Oldenlandia diffusa extracts exert antiproliferative and apoptotic effects on human breast cancer cells through ER?/Sp1-mediated p53 activation.  

PubMed

Breast cancer is the most frequent tumor and a major cause of death among women. Estrogens play a crucial role in breast tumor growth, which is the rationale for the use of hormonal antiestrogen therapies. Unfortunately, not all therapeutic modalities are efficacious and it is imperative to develop new effective antitumoral drugs. Oldenlandia diffusa (OD) is a well-known medicinal plant used to prevent and treat many disorders, especially cancers. The aim of this study was to investigate the effects of OD extracts on breast cancer cell proliferation. We observed that OD extracts strongly inhibited anchorage-dependent and -independent cell growth and induced apoptosis in estrogen receptor alpha (ER?)-positive breast cancer cells, whereas proliferation and apoptotic responses of MCF-10A normal breast epithelial cells were unaffected. Mechanistically, OD extracts enhance the tumor suppressor p53 expression as a result of an increased binding of ER?/Sp1 complex to the p53 promoter region. Finally, we isolated ursolic and oleanolic acids as the bioactive compounds able to upregulate p53 expression and inhibit breast cancer cell growth. These acids were greatly effective in reducing tamoxifen-resistant growth of a derivative MCF-7 breast cancer cell line resistant to the antiestrogen treatment. Our results evidence how OD, and its bioactive compounds, exert antiproliferative and apoptotic effects selectively in ER?-positive breast cancer cells, highlighting the potential use of these herbal extracts as breast cancer preventive and/or therapeutic agents. PMID:22213398

Gu, Guowei; Barone, Ines; Gelsomino, Luca; Giordano, Cinzia; Bonofiglio, Daniela; Statti, Giancarlo; Menichini, Francesco; Catalano, Stefania; Andò, Sebastiano

2012-10-01

303

Vascular Endothelial Growth Factor Receptor 2 (VEGFR-2) Plays a Key Role in Vasculogenic Mimicry Formation, Neovascularization and Tumor Initiation by Glioma Stem-like Cells  

PubMed Central

Human glioblastomas (GBM) are thought to be initiated by glioma stem-like cells (GSLCs). GSLCs also participate in tumor neovascularization by transdifferentiating into vascular endothelial cells. Here, we report a critical role of GSLCs in the formation of vasculogenic mimicry (VM), which defines channels lined by tumor cells to supply nutrients to early growing tumors and tumor initiation. GSLCs preferentially expressed vascular endothelial growth factor receptor-2 (VEGFR-2) that upon activation by VEGF, mediated chemotaxis, tubule formation and increased expression of critical VM markers by GSLCs. Knockdown of VEGFR-2 in GSLCs by shRNA markedly reduced their capacity of self-renewal, forming tubules, initiating xenograft tumors, promoting vascularization and the establishment of VM. Our study demonstrates VEGFR-2 as an essential molecule to sustain the “stemness” of GSLCs, their capacity to initiate tumor vasculature, and direct initiation of tumor.

Yao, Xiaohong; Ping, Yifang; Liu, Ying; Chen, Kequiang; Yoshimura, Teizo; Liu, Mingyong; Gong, Wanghua; Chen, Chong; Niu, Qin; Guo, Deyu; Zhang, Xia; Wang, Ji Ming; Bian, Xiuwu

2013-01-01

304

Analysis of the Xenopus laevis CCAAT-enhancer binding protein ? gene promoter demonstrates species-specific differences in the mechanisms for both auto-activation and regulation by Sp1  

PubMed Central

Transcription factors belonging to the CCAAT-enhancer binding protein (C/EBP) family have been implicated in the regulation of gene expression during differentiation, development and disease. Autoregulation is relatively common in the modulation of C/EBP gene expression and the murine and human C/EBP? genes have been shown to be auto-activated by different mechanisms. In the light of this finding, it is essential that autoregulation of C/EBP? genes from a wider range of different species be investigated in order to gauge the degree of commonality, or otherwise, that may exist. We report here studies that investigate the regulation of the Xenopus laevis C/EBP? gene (xC/EBP?). The –1131/+41 promoter region was capable of directing high levels of expression in both the human hepatoma Hep3B and the Xenopus kidney epithelial A6 cell lines, and was auto-activated by expression vectors specifying for xC/EBP? or xC/EBP?. Deletion analysis showed that the –321/+41 sequence was sufficient for both the constitutive promoter activity and auto-activation and electrophoretic mobility shift assays identified the interaction of C/EBPs and Sp1 to this region. Although deletion of either the C/EBP or the Sp1 site drastically reduced the xC/EBP? promoter activity, multimers of only the C/EBP site could confer autoregulation to a heterologous SV40 promoter. These results indicate that, in contrast to the human promoter and in common with the murine gene, the xC/EBP? promoter was subject to direct autoregulation. In addition, we demonstrate a novel species-specific action of Sp1 in the regulation of C/EBP? expression, with the factor able to repress the murine promoter but activate the Xenopus gene.

Kockar, Feray Tura; Foka, Pelagia; Hughes, Timothy R.; Kousteni, Stavroula; Ramji, Dipak P.

2001-01-01

305

Characterization of human deoxyribonuclease I gene (DNASE1) promoters reveals the utilization of two transcription-starting exons and the involvement of Sp1 in its transcriptional regulation.  

PubMed

Levels of deoxyribonuclease I (DNase I) activity in vivo have been shown to be altered by physiological and/or pathological processes. However, no information is available on the regulation of DNase I gene (DNASE1) expression in vivo or in vitro. We first mapped the transcription start sites of DNASE1 in human pancreas and in the DNase I-producing human pancreatic cancer cell line QGP-1, and revealed a novel site approximately 12 kb upstream of exon 1, which was previously believed to be the single transcription-starting exon. This initiation site marks an alternative starting exon, designated 1a. Exons 1 and 1a were used simultaneously as transcription-starting exons in pancreas and QGP-1 cells. Promoter assay, EMSA and chromatin immunoprecipitation analysis with QGP-1 cells showed the promoter region of exon 1a in which the Sp1 transcription factor is specifically involved in promoter activity. This is the first to be identified as a transcription factor responsible for gene expression of vertebrate DNase I genes. Furthermore, RT-PCR analysis indicated alternative splicing of human DNASE1 pre-mRNA in pancreas and QGP-1 cells. Only two transcripts among eight alternative splicing products identified can be translated to produce intact DNase I protein. These results suggest that human DNASE1 expression is regulated through the use of alternative promoter and alternative splicing. PMID:16771825

Kominato, Yoshihiko; Ueki, Misuzu; Iida, Reiko; Kawai, Yasuyuki; Nakajima, Tamiko; Makita, Chikako; Itoi, Masako; Tajima, Yutaka; Kishi, Koichiro; Yasuda, Toshihiro

2006-06-09

306

Theories of Play.  

ERIC Educational Resources Information Center

Discusses several theories of play advanced before the development of psychoanalysis, including the theories of surplus energy, recreation, and practice. Examines the psychoanalytical view advanced by Freud and others, which focuses on the emotional release of play and its role in discovery and learning. (MDM)

Peller, Lili E.

1996-01-01

307

Play and Digital Media  

ERIC Educational Resources Information Center

|This article examines how play is affected by computers and digital toys. Research indicates that when computer software targeted at children is problem-solving oriented and open-ended, children tend to engage in creative play and interact with peers in a positive manner. On the other hand, drill-and-practice programs can be quite boring and…

Johnson, James E.; Christie, James F.

2009-01-01

308

Let's Just Play  

ERIC Educational Resources Information Center

|Children have a right to play. The idea is so simple it seems self-evident. But a stroll through any toy superstore, or any half-hour of so-called "children's" programming on commercial TV, makes it clear that violence, not play, dominates what's being sold. In this article, the author discusses how teachers and parents share the responsibility…

Schmidt, Janet

2003-01-01

309

Play, Epideictic and Argument.  

ERIC Educational Resources Information Center

This paper explores the relationship between epideictic and argument, noting that the relationship is a "troublesome" one. The first part moves toward new definitions of epideictic and argument (taking the view that epideictic rises out of human play) and locates argument on the boundary where the play-world meets the "real" or "everyday." The…

Hoffman, David C.

310

The Play's the Thing  

ERIC Educational Resources Information Center

|The modern special education theater in the United States has hosted many plays, none with a larger or more diverse cast than the learning disabilities (LD) play. During the prologue, the children with LD were waiting in the wings, not yet identified as LD but there, nonetheless. With the advent of compulsory education in this country, awareness…

Bateman, Barbara

2005-01-01

311

An Invitation to Play.  

ERIC Educational Resources Information Center

The manual is intended to provide suggestions for play to parents of young children with exceptional educational needs. Nineteen types of activities are described and pictured, including make believe with boxes, dress-up activities, kitchen play, bubbles, small motor activities using beans and buttons, use of throw-away materials, painting,…

Lange, Jenny; Zieher, Connie

312

Guidelines for Medical Play.  

ERIC Educational Resources Information Center

|Medical play can be used as a tool to aid children in coping with stress related to hospitalization, surgery, medical care, and illness. Providing children with adequate guidance and appropriate supplies necessary for medical play, prepares children for medical experiences by enabling them to express their thoughts and feelings. Before attempting…

Ostrenga, Mary Anne

313

Growing Up with Play  

ERIC Educational Resources Information Center

|Many adults are afraid of boys' play today, believing that the aggression that is so common in boys' fantasies is dangerous and might make them become violent men. This personal reflection describes the importance of multiage play in showing little boys how to become big boys while encouraging empathy and emotional growth in older boys. The…

Katch, Jane

2008-01-01

314

The Fear of Play  

ERIC Educational Resources Information Center

|Real play--play that is initiated and directed by children and that bubbles up from within the child rather than being imposed by adults--has largely disappeared from the landscape of childhood in the United States. There are many reasons for this, such as the long hours spent in front of screens each day or in activities organized by adults. In…

Almon, Joan

2009-01-01

315

Evaluation of the formulation of solid dispersions by co-spray drying itraconazole with Inutec SP1, a polymeric surfactant, in combination with PVPVA 64  

Microsoft Academic Search

In order to improve the in vitro performance and stability of co-spray-dried itraconazole\\/Inutec SP1 systems, the influence of adding PVPVA 64, a polymer that is compatible with itraconazole, was evaluated. Dissolution tests were carried out on several itraconazole\\/PVPVA 64\\/Inutec SP1 compositions and spray-dried itraconazole\\/PVPVA 64 powders were used as references. The physicochemical properties of the samples were assessed with modulated

Sandrien Janssens; Jan Van Humbeeck; Guy Van den Mooter

2008-01-01

316

Substance P N-terminal fragment SP(1-7) attenuates chronic morphine tolerance and affects dynorphin B and nociceptin in rats.  

PubMed

The N-terminal substance P fragment SP(1-7) is known to modulate hyperalgesia and opioid withdrawal in animal models. This study examined the effects of intraperitoneal (i.p.) injections of SP(1-7) on chronic morphine tolerance and on the levels of dynorphin B (DYN B) and nociceptin/orphanin FQ (N/OFQ) in various brain areas of male Sprague-Dawley rats. Morphine tolerance was induced by subcutaneous injections of the opioid (10mg/kg) twice daily for 7 days. SP(1-7) injected i.p. (185 nmol/kg) 30 min prior to morphine reduced the development of morphine tolerance. Immunoreactive (ir) DYN B and N/OFQ peptide levels were measured in several areas of the central nervous system. Levels of ir DYN B in rats treated with SP(1-7) and morphine were decreased in the nucleus accumbens, substantia nigra and ventral tegmental area and increased in the frontal cortex. The ir N/OFQ levels were increased in the periaqueductal gray and decreased in the nucleus accumbens. Since the concentration profiles of the two peptides were altered by SP(1-7) in the areas that are implicated in the modulation of opioid tolerance and analgesia, it is suggested that DYN B and N/OFQ systems may be involved in the effects of SP(1-7) on opioid tolerance. PMID:21763376

Zhou, Qin; Carlsson, Anna; Hallberg, Mathias; Nyberg, Fred

2011-07-07

317

Shuttle Astronauts Play Chess  

NASA Video Gallery

STS-134 astronauts Greg Johnson and Greg Chamitoff ponder their next move for the Earth vs. Space chess match. The shuttle crew members also discuss their activities aboard the International Space Station and the benefits of playing chess.

Mark Garcia

2011-05-25

318

Play the MRI Game  

MedlinePLUS

... about the Nobel Prize Alfred Nobel's Life and Work Teachers' Questionnaire MRI Play MRI the Magnetic Miracle Game About the game In the MRI imaging technique, strong magnets and radio waves are used for getting images of inner ...

319

Kidney Role-Plays.  

ERIC Educational Resources Information Center

|Describes a study of the effectiveness of using role-play in teaching the functions of the kidney to secondary science students. Results suggest that the teaching technique is effective. (Author/WRM)|

Johnson, Gillian

1999-01-01

320

Play and Digital Media  

Microsoft Academic Search

This article examines how play is affected by computers and digital toys. Research indicates that when computer software targeted at children is problem-solving oriented and open-ended, children tend to engage in creative play and interact with peers in a positive manner. On the other hand, drill-and-practice programs can be quite boring and limit children's initiative and decision-making. Digital toys with

James E. Johnson; James F. Christie

2009-01-01

321

Power play game mechanics  

US Patent & Trademark Office Database

Method, article and apparatus for executing computer games, and in particular, computer-based racing games. In a racing game, a player may be allowed to earn one or more game play options which may be exercised during the race. The game play options, when exercised, may modify the predefined race path to create an advantage for the player or a disadvantage to the competitors.

Baynes; Nick (Brighton, GB); Jefferies; David (Hove, GB); Green; Jason (Brighton, GB); Hassan; Serkan (Brighton, GB)

2013-02-05

322

Complete genome sequence of Terriglobus saanensis type strain SP1PR4(T), an Acidobacteria from tundra soil.  

PubMed

Terriglobus saanensis SP1PR4(T) is a novel species of the genus Terriglobus. T. saanensis is of ecological interest because it is a representative of the phylum Acidobacteria, which are dominant members of bacterial soil microbiota in Arctic ecosystems. T. saanensis is a cold-adapted acidophile and a versatile heterotroph utilizing a suite of simple sugars and complex polysaccharides. The genome contained an abundance of genes assigned to metabolism and transport of carbohydrates including gene modules encoding for carbohydrate-active enzyme (CAZyme) family involved in breakdown, utilization and biosynthesis of diverse structural and storage polysaccharides. T. saanensis SP1PR4(T) represents the first member of genus Terriglobus with a completed genome sequence, consisting of a single replicon of 5,095,226 base pairs (bp), 54 RNA genes and 4,279 protein-coding genes. We infer that the physiology and metabolic potential of T. saanensis is adapted to allow for resilience to the nutrient-deficient conditions and fluctuating temperatures of Arctic tundra soils. PMID:23450133

Rawat, Suman R; Männistö, Minna K; Starovoytov, Valentin; Goodwin, Lynne; Nolan, Matt; Hauser, Lauren; Land, Miriam; Davenport, Karen Walston; Woyke, Tanja; Häggblom, Max M

2012-09-26

323

Complete genome sequence of Terriglobus saanensis type strain SP1PR4T, an Acidobacteria from tundra soil  

SciTech Connect

Terriglobus saanensis SP1PR4T is a novel species of the genus Terriglobus. T. saanensis is of ecological interest because it is a representative of the phylum Acidobacteria, which are dominant members of bacterial soil microbiota in Arctic ecosystems. T. saanensis is a cold-adapted acidophile and a versatile heterotroph utilizing a suite of simple sugars and complex polysaccharides. The genome contained an abundance of genes assigned to metabolism and transport of carbohydrates including gene modules encoding for carbohydrate-active enzyme (CAZyme) family involved in breakdown, utilization and biosynthesis of diverse structural and storage polysaccharides. T. saanensis SP1PR4T represents the first member of genus Terriglobus with a completed genome sequence, consisting of a single replicon of 5,095,226 base pairs (bp), 54 RNA genes and 4,279 protein-coding genes. We infer that the physiology and metabolic potential of T. saanensis is adapted to allow for resilience to the nutrient-deficient conditions and fluctuating temperatures of Arctic tundra soils.

Rawat, Suman R. [Rutgers University; Mannisto, Minna [Finnish Forest Research Institute, Parkano, Finland; Starovoytov, Valentin [Rutgers University; Goodwin, Lynne A. [Los Alamos National Laboratory (LANL); Nolan, Matt [U.S. Department of Energy, Joint Genome Institute; Hauser, Loren John [ORNL; Land, Miriam L [ORNL; Davenport, Karen W. [Los Alamos National Laboratory (LANL); Woyke, Tanja [U.S. Department of Energy, Joint Genome Institute; Haggblom, Max [Rutgers University

2012-01-01

324

Tat and trans-activation-responsive (TAR) RNA-independent induction of HIV-1 long terminal repeat by human and murine cyclin T1 requires Sp1.  

PubMed

P-TEFb, cyclin T1 + CDK9, is needed for the expression of cellular promoters and primate lentiviral long terminal repeats (LTRs). Curiously, cellular and lentiviral promoters differ dramatically in the requirements for positive transcriptional elongation factor (P-TEF) b activity. Lentiviral LTRs, but not cellular promoters, need an RNA-associated P-TEFb/Tat/TAR (trans-activation-responsive) RNA ternary complex. Ternary complex defective murine cycT1 is apparently inactive for lentiviral transcription. Why P-TEFb requires Tat/TAR for LTRs but not for cellular promoters remains unknown. To explore this question, we sought to determine whether DNA targeting of murine and human cyclin T1 can reconstitute a Tat/TAR-independent activity to the HIV-1 LTR. In the absence of Tat and TAR, we found that both HuCycT1 and MuCycT1 can robustly activate the HIV-1 LTR. We further showed that Sp1 is necessary and sufficient for this DNA-targeted activity. Thus, like cellular promoters, HIV-1 LTR can use P-TEFb function without a Tat/TAR RNA complex. This activity could explain recent findings of robust HIV-1 replication in rat cells that cannot form a P-TEFb/Tat/TAR moiety. PMID:12458222

Yedavalli, Venkat S R K; Benkirane, Monsef; Jeang, Kuan-Teh

2002-11-27

325

BMP-2 and TGF-? Stimulate Expression of ?1,3-Glucuronosyl Transferase 1 (GlcAT-1) in Nucleus Pulposus Cells Through AP1, TonEBP, and Sp1: Role of MAPKs  

PubMed Central

The goal of the study was to investigate bone morphogenetic protein 2 (BMP-2) and transforming growth factor ? (TGF-?) control of the expression of ?1,3-glucuronosyl transferase 1 (GlcAT-1), an important regulator of chondroitin sulfate synthesis in cells of the nucleus pulposus. Treatment with both growth factors resulted in induction of GlcAT-1 expression and promoter activity. Deletion analysis indicated that promoter constructs lacking AP1 and TonE sites were unresponsive to growth factor treatment. Experiments using dominant-negative proteins showed that these transcription factors along with Sp1 were required for induction of GlcAT-1 promoter activity. Moreover, when either AP1 or TonE binding sites were mutated, induction was suppressed. Both BMP-2 and TGF-? increased c-Jun and TonEBP expression and phosphorylation of transactivation domains. We investigated the role of the mitogen-activated protein kinase (MAPK) signaling pathway following growth factor treatment; a robust and transient activation of ERK1/2, p38, and JNK was noted. Treatment with MAPK inhibitors blocked BMP-2- and TGF-?-induced AP1 reporter function, GlcAT-1 expression, and GAG accumulation. We found that DN-ERK1 but not DN-ERK2 resulted in suppression of growth factor–mediated induction of GlcAT-1 promoter activity; we also showed that p38? was important in GlcAT-1 activation. Results of these studies demonstrate that BMP-2 and TGF-? regulate GlcAT-1 expression in nucleus pulposus cells through a signaling network comprising MAPK, AP1, Sp1, and TonEBP. It is concluded that by controlling both GAG and aggrecan synthesis, these growth factors positively influence disk cell function. © 2010 American Society for Bone and Mineral Research.

Hiyama, Akihiko; Gogate, Shilpa S; Gajghate, Sachin; Mochida, Joji; Shapiro, Irving M; Risbud, Makarand V

2010-01-01

326

Mutation in the Sp1 motif of the bovine leptin gene affects its expression.  

PubMed

Leptin is expressed mainly by adipocytes and plays a crucial role in the regulation of energy expenditure, food intake, and adiposity. Using PCR-heteroduplex analysis and sequencing, we investigated a C/G substitution in the promoter region of the bovine leptin gene. Application of the electrophoretic mobility shift assay showed that the C-->G transversion decreased the leptin gene promoter binding capacity for nuclear proteins. With real-time PCR and Western blotting, we showed that the leptin expression level was higher in cattle with the CC than with the GG genotype. PMID:16416093

Adamowicz, Tatiana; Flisikowski, Krzysztof; Starzy?ski, Rafa?; Zwierzchowski, Lech; Swito?ski, Marek

2006-01-13

327

Curcumin Down-Regulates DNA Methyltransferase 1 and Plays an Anti-Leukemic Role in Acute Myeloid Leukemia  

PubMed Central

Bioactive components from dietary supplements such as curcumin may represent attractive agents for cancer prevention or treatment. DNA methylation plays a critical role in acute myeloid leukemia (AML) development, and presents an excellent target for treatment of this disease. However, it remains largely unknown how curcumin, a component of the popular Indian spice turmeric, plays a role in DNA hypomethylation to reactivate silenced tumor suppressor genes and to present a potential treatment option for AML. Here we show that curcumin down-regulates DNMT1 expression in AML cell lines, both in vitro and in vivo, and in primary AML cells ex vivo. Mechanistically, curcumin reduced the expression of positive regulators of DNMT1, p65 and Sp1, which correlated with a reduction in binding of these transcription factors to the DNMT1 promoter in AML cell lines. This curcumin-mediated down-regulation of DNMT1 expression was concomitant with p15INK4B tumor suppressor gene reactivation, hypomethylation of the p15INK4B promoter, G1 cell cycle arrest, and induction of tumor cell apoptosis in vitro. In mice implanted with the human AML MV4–11 cell line, administration of curcumin resulted in remarkable suppression of AML tumor growth. Collectively, our data indicate that curcumin shows promise as a potential treatment for AML, and our findings provide a basis for future studies to test the clinical efficacy of curcumin – whether used as a single agent or as an adjuvant – for AML treatment.

Yu, Jianhua; Peng, Yong; Wu, Lai-Chu; Xie, Zhiliang; Deng, Youcai; Hughes, Tiffany; He, Shun; Mo, XiaoKui; Chiu, Ming; Wang, Qi-En; He, Xiaoming; Liu, Shujun; Grever, Michael R.; Chan, Kenneth K.; Liu, Zhongfa

2013-01-01

328

Loss of NECL1, a novel tumor suppressor, can be restored in glioma by HDAC inhibitor-Trichostatin A through Sp1 binding site.  

PubMed

Nectin-like molecule 1 (NECL1)/CADM3/IGSF4B/TSLL1/SynCAM3 is a neural tissue-specific immunoglobulin-like cell-cell adhesion molecule downregulated at the mRNA level in 12 human glioma cell lines. Here we found that the expression of NECL1 was lost in six glioma cell lines and 15 primary glioma tissues at both RNA and protein levels. Re-expression of NECL1 into glioma cell line U251 would repress cell proliferation in vitro by inducing cell cycle arrest. And also NECL1 could decrease the growth rate of tumors in nude mice in vivo. To further investigate the mechanism why NECL1 was silenced in glioma, the basic promoter region located at -271 to +81 in NECL1 genomic sequence was determined. DNA bisulfite sequencing was performed to study the methylation status of CpG islands in NECL1 promoter; however, no hypermethylated CpG site was found. Additionally, the activity of histone deacetylase (HDACs) in glioma was higher than that in normal brain tissues, and the expression of NECL1 in glioma cell lines could be reactivated by HDACs inhibitor-Trichostatin A (TSA). So the loss of NECL1 in glioma was at least partly caused by histone deacetylation. Luciferase reporter assays, chromatin immunoprecipitation and co-immunoprecipitation (co-IP) assays indicated that Sp1 played an important role in this process by binding to either HDAC1 in untreated glioma cells or p300/CBP in TSA treated cells. Our finding suggests that NECL1 may act as a tumor suppressor in glioma and loss of it in glioma may be caused by histone deacetylation. PMID:19062177

Gao, Jing; Chen, Tao; Liu, Jin; Liu, Wei; Hu, Guangyu; Guo, Xiaoxiao; Yin, Bin; Gong, Yanhua; Zhao, Jizong; Qiang, Boqin; Yuan, Jiangang; Peng, Xiaozhong

2009-07-01

329

Playing It Safe.  

ERIC Educational Resources Information Center

|Offers tips for avoiding sports-related injuries: (1) expect more of coaches; (2) develop an athletic-safety plan; (3) consider hiring an athletic trainer; (4) check facilities and equipment regularly; (5) recognize athletes' limitations; (6) take precautions beyond the playing field; and (7) check liability coverage and obtain informed consent.…

Jones, Rebecca

1997-01-01

330

Playing with danger.  

PubMed

Young people who sit still for hours playing computer games can double their risk of potentially fatal blood clots. The charity Lifeblood is alerting nurses to 'e-thrombosis'. It is calling on them to ensure young people are aware of the risks of prolonged immobility and the need to take regular breaks from gaming or using a computer. PMID:23061127

Pearce, Lynne

331

The neurobiology of play  

Microsoft Academic Search

A large volume of neurobiological research has been conducted in recent years, almost all of which has been considered solely from the perspective of biology. However, most of the insights gained through this research are also valuable for the game research field. This paper discusses the implications of existing research in neurobiology to the play of games (including, but not

Chris Bateman; Lennart E. Nacke

2010-01-01

332

The Paradoxes of Play.  

ERIC Educational Resources Information Center

The article makes a case against the structuring of intramural sports programs on the basis of the varsity athletics model, arguing that the latter model's components of competition and aggression mar the former's intrinsic rewards of play, creativity, and enhanced human relationships. (CB)

Rokosz, Francis M.

1988-01-01

333

Learn to Play Chess!  

NSDL National Science Digital Library

This tutorial uses video and interactives to teach the basic moves and other features of the game of chess. The site offers other opportunities to learn and play chess online against other registered opponents. If under 13 yers of age, a learner must have a parent or coach register first and then create learner accounts.

2013-01-01

334

Kazantzakis's Metachristian Play  

Microsoft Academic Search

The play Nikifóros Fokás, written in first draft in 1915, shows Kazantzakis assimilating Christian materials to a basically aesthetic philosophy in order to develop a “metachristian” world-view that treats our futile presence on earth. This metachristian view replaces the Christian assurance that happiness comes from the observance of certain precepts of behavior that lead to the reward of heavenly bliss;

Peter Bien

335

Strategic Levels of Play.  

ERIC Educational Resources Information Center

|This article presents a broad ranging philosophical and theoretical argument for improving the education of young children through a greater understanding of developmental child psychology. Notes that play is essential for individual mental development, and must be used in educational settings. Maintains that pure scientific research is simply a…

Lima, Lauro de Oliveira

1986-01-01

336

E-Play  

Microsoft Academic Search

E-Play is an electronic entertainer, pacifier, and communicator that meets needs of very small children, from infancy to preschool, is robust and simple to control, and is activated by touch only. Children choose activities by touching a picture, thus it is a natural design for use with kids having no computer experience. We have explored two types of contents -

Claudia V. Goldman; Scott Kirkpatricki

2002-01-01

337

Everyone Here Can Play.  

ERIC Educational Resources Information Center

|An action-research project examined how implementation of an inclusive rule, "You can't say you can't play," at a Syracuse, New York, elementary school influenced children's informal social relationships, focusing particularly on children with disabilities. Overall, the rule has helped create a rich discourse about inclusion issues, providing a…

Sapon-Shevin, Mara; Dobbelaere, Anne; Corrigan, Cathleen; Goodman, Kathleen; Mastin, Mary

1998-01-01

338

"Playing" with Science  

ERIC Educational Resources Information Center

When faced with a multitude of tasks, any opportunity to "kill two birds with one stone" is welcome. Drama has always excited the author: as a child performing in plays, later as a student and now as a teacher directing performances and improvising within lessons. The author was lucky enough to have inspirational teachers during his primary and…

Allen, Dave

2012-01-01

339

Abstraction through Game Play  

ERIC Educational Resources Information Center

|This paper examines the computer game play of an 11-year-old boy. In the course of building a virtual house he developed and used, without assistance, an artefact and an accompanying strategy to ensure that his house was symmetric. We argue that the creation and use of this artefact-strategy is a mathematical abstraction. The discussion…

Avraamidou, Antri; Monaghan, John; Walker, Aisha

2012-01-01

340

Bicentennial Plays and Programs.  

ERIC Educational Resources Information Center

This book contains royalty-free material on bicentennial themes for presentation by schools and amateur groups. The first section, Plays and Pageants, contains "Our Great Declaration,""A Star for Old Glory,""Sing, America, Sing,""Washington Marches On,""When Freedom Was News," and "A Dish of Green Peas." The second section, Playlets and…

Fisher, Aileen

341

Playing with Light.  

ERIC Educational Resources Information Center

Challenges the belief that high stakes tests are the keystone of students' educational attainment, describing a series of exploratory workshops, developed in reaction to this issue, in which teachers (as essential preparation for developing students' curiosity) deepened their understanding of the principles of physics by playing with light. Such…

Cavicchi, Elizabeth; Lucht, Petra; Hughes-McDonnell, Fiona

2000-01-01

342

Playing House: Stories  

Microsoft Academic Search

Playing House: Stories is a collection of short fiction submitted in partial fulfillment of the requirements for the MFA. Each story stands on its own and features a unique protagonist, but some commonalities in theme and subject matter extend across the collection. The stories realistically depict Americans in their twenties during the early twenty-first century. All of the stories involve

George Zamzow

2009-01-01

343

Sp1 trans-activates and is required for maximal aldosterone induction of the ?ENaC gene in collecting duct cells.  

PubMed

The epithelial Na(+) channel (ENaC) in the distal nephron constitutes the rate-limiting step for renal sodium reabsorption. Aldosterone increases tubular sodium absorption in large part by increasing ?ENaC transcription in collecting duct principal cells. We previously reported that Af9 binds to +78/+92 of ?ENaC and recruits Dot1a to repress basal and aldosterone-sensitive ?ENaC transcription in mouse inner medullary collecting duct (mIMCD)3 cells. Despite this epigenetic repression, basal ?ENaC transcription is still evident and physiologically necessary, indicating basal operation of positive regulators. In the present study, we identified Sp1 as one such regulator. Gel shift and antibody competition assays using a +208/+240 probe revealed DNA-Sp1-containing complexes in mIMCD3 cells. Mutation of the +222/+229 element abrogated Sp1 binding in vitro and in promoter-reporter constructs stably expressed in mIMCD3 cells. Compared with the wild-type promoter, an ?ENaC promoter-luciferase construct with +222/+229 mutations exhibited much lower activity and impaired trans-activation in Sp1 overexpression experiments. Conversely, Sp1 knockdown inhibited endogenous ?ENaC mRNA and the activity of the wild-type ?ENaC promoter but not the mutated construct. Aldosterone triggered Sp1 recruitment to the ?ENaC promoter, which was required for maximal induction of ?ENaC promoter activity and was blocked by spironolactone. Sequential chromatin immunoprecipitation assays and functional tests of +78/+92 and +222/+229 ?ENaC promoter mutants indicated that while Sp1, Dot1a, and Af9 co-occupy the ?ENaC promoter, the Sp1 effects are functionally independent from Dot1a and Af9. In summary, Sp1 binding to a cis-element at +222/+229 represents the first identified constitutive driver of ?ENaC transcription, and it contributes to maximal aldosterone trans-activation of ?ENaC. PMID:23804453

Yu, Zhiyuan; Kong, Qun; Kone, Bruce C

2013-06-26

344

Persistence of Ha-ras-induced metastatic potential of SP1 mouse mammary tumors despite loss of the Ha-ras shuttle vector.  

PubMed Central

Previous studies have shown that the SP1 mouse mammary adenocarcinoma cell line, which is tumorigenic but nonmetastatic, acquires metastatic potential when transfected with the activated human Ha-ras gene. In addition, the process of calcium phosphate-mediated DNA transfection, as well as treatment with the calcium ionophore A23187 or with phorbol 12-myristate 13-acetate, can also result in heritable changes in the malignant behavior of SP1 cells. It was of interest, therefore, to determine whether the metastatic consequences of Ha-ras oncogene expression in SP1 cells are a primary effect of the transfected gene or whether heritable secondary changes are induced by Ha-ras oncogene expression. In the latter case, continued expression of the Ha-ras oncogene would not be required to maintain the metastatic phenotype. To test this hypothesis we introduced the Ha-ras oncogene into SP1 cells on a shuttle vector in which maintenance of the vector was dependent on selection for resistance to the antibiotic G418. Subclones which had lost the transfected Ha-ras gene were subsequently isolated following growth in nonselective medium. The Ha-ras-transfected clones and the revertant subclones were found to be equally metastatic, indicating that transfection with the Ha-ras gene does induce stable secondary changes in the metastatic phenotype of SP1 cells. Images

Schlatter, B; Waghorne, C G

1992-01-01

345

Time perspective as a predictor of massive multiplayer online role-playing game playing.  

PubMed

This article focuses on the relationship between the time perspective (TP) personality trait and massive multiplayer online role-playing game (MMORPG) playing. We investigate the question of frequency of playing. The TP was measured with Zimbardo's TP Inventory (ZTPI), which includes five factors-past negative, past positive, present hedonistic, present fatalistic, and future. The study used data from 154 MMORPG players. We demonstrated that TP partially explained differences within a group of players with respect to the frequency of playing. Significant positive correlations were found between present factors and the amount of time spent playing MMORPGs, and significant negative correlation was found between the future factor and the time spent playing MMORPGs. Our study also revealed the influence of future-present balance on playing time. Players who scored lower in future-present balance variables (their present score was relatively high compared with their future score) reported higher values in playing time. In contrast to referential studies on TP and drug abuse and gambling, present fatalistic TP was demonstrated to be a stronger predictor of extensive playing than present hedonistic TP, which opened the question of motivation for playing. The advantage of our study compared with other personality-based studies lies in the fact that TP is a stable but malleable personality trait with a direct link to playing behavior. Therefore, TP is a promising conceptual resource for excessive playing therapy. PMID:22032796

Lukavska, Katerina

2011-10-27

346

Play It Safe  

NSDL National Science Digital Library

This fast-paced strategy game combines probability and mathematical reasoning, and helps hone memory and mental math skills. Players turn over cards until they get a total as close as possible to 40. They need to decide when to get out of the game, since they don't want to go over 40--so they need to pay careful attention to which cards have already been played. Available as a web page or downloadable pdf. Also available in Spanish.

Terc

2010-01-01

347

Building upon everyday play  

Microsoft Academic Search

Most of today's video game strategies are based on a static set of game controls and player actions that remain oblivious to the player's context and own creativity. Building Upon Everyday Play is the result of a collaboration of Control Freaks, a pervasive gaming experience project, and Exemplar, a toolkit that uses programming-by-demonstration to author sensor-based interactions. In combination, Building

Haiyan Zhang; Bjöern Hartmann

2007-01-01

348

Plug and Play Encryption  

Microsoft Academic Search

\\u000a We present a novel protocol for secret key exchange that is provably secure against attacks by an adversary that is free to\\u000a attack zero, one, or both parties in an adaptive fashion, at any time. This high degree of robustness enables larger, multiparty\\u000a interactions (including multiparty secure computations) to substitute our protocol for secure private channels in a simple,\\u000a plug-and-play

Donald Beaver

1997-01-01

349

Eat Smart. Play Hard.  

NSDL National Science Digital Library

The Food and Nutrition Service of the US Department of Agriculture offers online educational material as part of "Eat Smart. Play Hard." -- a public information campaign designed to promote healthy living in American children. While the site and its materials are geared for use by state and local program coordinators, anyone is welcome to download the available information and activity sheets. Click on Cool Stuff for Kids for nutrition-related puzzles and games. Parents Place offers informational brochures and an educational bookmark.

350

Ancient properties of spider silks revealed by the complete gene sequence of the prey-wrapping silk protein (AcSp1).  

PubMed

Spider silk fibers have impressive mechanical properties and are primarily composed of highly repetitive structural proteins (termed spidroins) encoded by a single gene family. Most characterized spidroin genes are incompletely known because of their extreme size (typically >9 kb) and repetitiveness, limiting understanding of the evolutionary processes that gave rise to their unusual gene architectures. The only complete spidroin genes characterized thus far form the dragline in the Western black widow, Latrodectus hesperus. Here, we describe the first complete gene sequence encoding the aciniform spidroin AcSp1, the primary component of spider prey-wrapping fibers. L. hesperus AcSp1 contains a single enormous (?19 kb) exon. The AcSp1 repeat sequence is exceptionally conserved between two widow species (?94% identity) and between widows and distantly related orb-weavers (?30% identity), consistent with a history of strong purifying selection on its amino acid sequence. Furthermore, the 16 repeats (each 371-375 amino acids long) found in black widow AcSp1 are, on average, >99% identical at the nucleotide level. A combination of stabilizing selection on amino acid sequence, selection on silent sites, and intragenic recombination likely explains the extreme homogenization of AcSp1 repeats. In addition, phylogenetic analyses of spidroin paralogs support a gene duplication event occurring concomitantly with specialization of the aciniform glands and the tubuliform glands, which synthesize egg-case silk. With repeats that are dramatically different in length and amino acid composition from dragline spidroins, our L. hesperus AcSp1 expands the knowledge base for developing silk-based biomimetic technologies. PMID:23155003

Ayoub, Nadia A; Garb, Jessica E; Kuelbs, Amanda; Hayashi, Cheryl Y

2012-11-15

351

Ancient Properties of Spider Silks Revealed by the Complete Gene Sequence of the Prey-Wrapping Silk Protein (AcSp1)  

PubMed Central

Spider silk fibers have impressive mechanical properties and are primarily composed of highly repetitive structural proteins (termed spidroins) encoded by a single gene family. Most characterized spidroin genes are incompletely known because of their extreme size (typically >9 kb) and repetitiveness, limiting understanding of the evolutionary processes that gave rise to their unusual gene architectures. The only complete spidroin genes characterized thus far form the dragline in the Western black widow, Latrodectus hesperus. Here, we describe the first complete gene sequence encoding the aciniform spidroin AcSp1, the primary component of spider prey-wrapping fibers. L. hesperus AcSp1 contains a single enormous (?19 kb) exon. The AcSp1 repeat sequence is exceptionally conserved between two widow species (?94% identity) and between widows and distantly related orb-weavers (?30% identity), consistent with a history of strong purifying selection on its amino acid sequence. Furthermore, the 16 repeats (each 371–375 amino acids long) found in black widow AcSp1 are, on average, >99% identical at the nucleotide level. A combination of stabilizing selection on amino acid sequence, selection on silent sites, and intragenic recombination likely explains the extreme homogenization of AcSp1 repeats. In addition, phylogenetic analyses of spidroin paralogs support a gene duplication event occurring concomitantly with specialization of the aciniform glands and the tubuliform glands, which synthesize egg-case silk. With repeats that are dramatically different in length and amino acid composition from dragline spidroins, our L. hesperus AcSp1 expands the knowledge base for developing silk-based biomimetic technologies.

Ayoub, Nadia A.; Garb, Jessica E.; Kuelbs, Amanda; Hayashi, Cheryl Y.

2013-01-01

352

Characterization of a marine-isolated mercury-resistant Pseudomonas putida strain SP1 and its potential application in marine mercury reduction  

Microsoft Academic Search

The Pseudomonas putida strain SP1 was isolated from marine environment and was found to be resistant to 280 ?M HgCl2. SP1 was also highly resistant to other metals, including CdCl2, CoCl2, CrCl3, CuCl2, PbCl2, and ZnSO4, and the antibiotics ampicillin (Ap), kanamycin (Kn), chloramphenicol (Cm), and tetracycline (Tc). mer operon, possessed by most mercury-resistant bacteria, and other diverse types of resistant

Weiwei Zhang; Lingxin Chen; Dongyan Liu

353

An Sp1/Sp3 Site in the Downstream Region of Varicella-Zoster Virus (VZV) oriS Influences Origin-Dependent DNA Replication and Flanking Gene Transcription and Is Important for VZV Replication In Vitro and in Human Skin  

PubMed Central

The distribution and orientation of origin-binding protein (OBP) sites are the main architectural contrasts between varicella-zoster virus (VZV) and herpes simplex virus (HSV) origins of DNA replication (oriS). One important difference is the absence of a downstream OBP site in VZV, raising the possibility that an alternative cis element may replace its function. Our previous work established that Sp1, Sp3, and YY1 bind to specific sites within the downstream region of VZV oriS; we hypothesize that one or both of these sites may be the alternative cis element(s). Here, we show that the mutation of the Sp1/Sp3 site decreases DNA replication and transcription from the adjacent ORF62 and ORF63 promoters following superinfection with VZV. In contrast, in the absence of DNA replication or in transfection experiments with ORF62, only ORF63 transcription is affected. YY1 site mutations had no significant effect on either process. Recombinant viruses containing these mutations were then constructed. The Sp1/Sp3 site mutant exhibited a significant decrease in virus growth in MeWo cells and in human skin xenografts, while the YY1 site mutant virus grew as well as the wild type in MeWo cells, even showing a late increase in VZV replication in skin xenografts following infection. These results suggest that the Sp1/Sp3 site plays an important role in both VZV origin-dependent DNA replication and ORF62 and ORF63 transcription and that, in contrast to HSV, these events are linked during virus replication.

Robinson, Makeda; Sommer, Marvin; Arvin, Ann; Hay, John; Ruyechan, William T.

2012-01-01

354

PlayStation purpura.  

PubMed

A 16-year-old boy presented with a number of asymptomatic pigmented macules on the volar aspect of his index fingers. Dermoscopy of each macule revealed a parallel ridge pattern of homogenous reddish-brown pigment. We propose that these lesions were induced by repetitive trauma from a Sony PlayStation 3 (Sony Corporation, Tokyo, Japan) vibration feedback controller. The lesions completely resolved following abstinence from gaming over a number of weeks. Although the parallel ridge pattern is typically the hallmark for early acral lentiginous melanoma, it may be observed in a limited number of benign entities, including subcorneal haematoma. PMID:20695869

Robertson, Susan J; Leonard, Jane; Chamberlain, Alex J

2010-08-01

355

Disease Role Play  

NSDL National Science Digital Library

Students in collaborative groups will develop an action plan to address a new disease. This activity provides 3 roles for student participation: scientist, public health official and community leader. Each group member will be required to remain within the parameters described by the scenario during the role play. For example, the scientists will be given a data sheet the they will need to interpret. This group member will be the only one with knowledge of the disease. Only this person will act as a disease expert. Once the groups have an opportunity to read their scenarios and prepare for a committee meeting, they will meet and devise an action plan.

Chris Kuka (Bend Senior High School REV)

1994-07-30

356

Playing Connect Three  

NSDL National Science Digital Library

This activity promotes students to explore and analyze the number of different ways of achieving each of the specific outcomes when adding and subtracting positive and negative integers while playing the game, "Connect Three." By answering key questions, the players work out a strategy for improving their chances of winning the game. The Teachers' Notes page offers suggestions for implementation, discussion questions, ideas for support, extension and answers to questions are provided. A pdf of the game board and a spreadsheet to simulate tossing the dice are linked.

2008-01-01

357

Baroreceptor Reflex Role Play  

NSDL National Science Digital Library

In this activity about the baroreceptor reflex (BR) arc (page 123 of the PDF), learners discover the importance of maintaining adequate arterial blood pressure through a role playing exercise. This activity will model how the brain processes information and sends out signals to the heart and arteries. Learners can also consider how this affects astronauts in the microgravity environment of space. The lesson guide, part of NASA's "The Brain in Space: A Teacher's Guide with Activities for Neuroscience," includes background information and evaluation strategies. Note: this activity requires 9 learners per group.

Macleish, Marlene Y.; Mclean, Bernice R.

2012-06-26

358

Mitochondrial Transcription Factor A and Its Downstream Targets Are Up-regulated in a Rat Hepatoma*  

PubMed Central

Mitochondrial transcription factor A is a key regulator involved in mitochondrial DNA transcription and replication. In a poorly differentiated rat hepatoma, Morris hepatoma 3924A, the mRNA and protein levels of this factor were elevated about 10- and 11-fold, respectively, relative to the host liver. The mRNA levels for the hepatoma cytochrome c oxidase I, II, and NADH dehydrogenase 5, 6, the downstream targets of Tfam, were augmented 10-, 8-, 5-, and 3-fold, respectively. Interestingly, Tfam was also found in the hepatoma nucleus. The mRNA levels for nuclear respiratory factor 1 and 2 (NRF-1 and -2), the proteins that are known to interact with specific regulatory elements on human TFAM promoter, were 5- and 3-fold higher, respectively, in the hepatoma relative to the host liver. Unlike the human promoter, the rat Tfam promoter did not form a specific complex with the NRF-1 in the liver or hepatoma nuclear extracts, which is consistent with the absence of an NRF-1 consensus sequence in the proximal rat promoter. A single specific complex formed between the rat promoter and the NRF-2 protein was comparable in the two extracts. The DNA binding activity of Sp1 in the hepatoma nuclear extract was 4-fold greater than that in the liver extract. In vivo genomic footprinting showed occupancy of NRF-2 and Sp1 consensus sites on the promoter of rat Tfam gene. Tfam was also up-regulated in other hepatoma cells. Together, these results show up-regulation of Tfam in some tumors, particularly the liver tumors. Further, the relatively high level of Sp1 binding to the promoter in the hepatoma could play a major role in the up-regulation of Tfam in these tumor cells.

Dong, Xiaocheng; Ghoshal, Kalpana; Majumder, Sarmila; Yadav, Satya P.; Jacob, Samson T.

2008-01-01

359

Who played the Raptors?  

NSDL National Science Digital Library

In this online activity, students analyze predictions made by sportswriters about which basketball teams will win to determine which teams are playing each other. The Getting Started link describes how to set up a table to organize the given information. The activity is one of 80 mathematical challenges featured on the Figure This! web site, where real-world uses of mathematics are emphasized. The solution illustrates and explains three different ways to successfully organize information, including using a Venn diagram. The related questions challenge students to use logic and organizational skills to analyze data in a pet survey and to draw a conclusion from information about automobile preferences. Background information about famous names in the field of logic and a list of literary books containing logic puzzles are included. Copyright 2005 Eisenhower National Clearinghouse

National Council of Teachers of Mathematics (NCTM)

2002-01-01

360

The HSP90 inhibitor 17-allylamino-17-demethoxygeldanamycin modulates radiosensitivity by downregulating serine/threonine kinase 38 via Sp1 inhibition.  

PubMed

The ansamycin-based HSP90 inhibitor 17-AAG (17-allylamino-17-demethoxygeldanamycin) combats tumors and has been shown to modulate cellular sensitivity to radiation, prompting researchers to use 17-AAG as a radiosensitizer. 17-AAG causes the degradation of several oncogenic and signaling proteins. We previously demonstrated that oxidative stress activates serine/threonine kinase 38 (STK38), a member of the protein kinase A (PKA)/PKG/PKC-like family. In the present study, we investigated how 17-AAG affects STK38 expression, and evaluated STK38's role in the regulation of radiosensitivity. We found that 17-AAG depleted cellular STK38 and reduced STK38's kinase activity. Importantly, 17-AAG downregulated the stk38 gene expression. Deletion analysis and site-directed mutagenesis experiments demonstrated that Sp1 was required for the stk38 promoter activity. Treatment with 17-AAG inhibited Sp1's binding to the stk38 promoter by decreasing the amount of Sp1 and knocking down Sp1 reduced STK38 expression. Moreover, 17-AAG treatment or STK38 knockdown enhanced the radiosensitivity of HeLa cells. Our data provide a novel mechanism, mediated by stk38 downregulation, by which 17-AAG radiosensitizes cells. PMID:23886587

Enomoto, Atsushi; Fukasawa, Takemichi; Takamatsu, Nobuhiko; Ito, Michihiko; Morita, Akinori; Hosoi, Yoshio; Miyagawa, Kiyoshi

2013-07-22

361

Investigation of the Sp1-binding site polymorphism within the COL1A1 gene in participants with Achilles tendon injuries and controls.  

PubMed

Sequence variants within the type V collagen (COL5A1) and tenascin C (TNC) genes have to date been shown to be associated with chronic Achilles tendinopathies and/or spontaneous Achilles tendon ruptures. Type V collagen and tenascin C are quantitatively minor components of tendon, while type I collagen is the major structural component. There is increased expression of the COL1A1 gene, which encodes for the alpha1 chain of type I collagen, in the painful Achilles tendon. A functional Sp1-binding site polymorphism (SNP rs1800012; IVS1+1023G>T) within this gene has been shown to be associated with several connective tissue disorders. The aim of this study was to determine whether the Sp1-binding site polymorphism within the COL1A1 gene is associated with chronic Achilles tendinopathies and/or spontaneous Achilles tendon ruptures. Achilles tendinopathy (n=85), Achilles rupture (n=41) and asymptomatic control (n=125) participants were genotyped for the COL1A1 Sp1-binding site polymorphism. There were no observed statistical differences in the genotype (p=0.602) or allele (p=0.694) distributions between the groups. In conclusion, this study has shown that there is no association between the Sp1-binding site polymorphism within the first intron of COL1A1 and Achilles tendinopathy or Achilles tendon rupture within the population studied. PMID:18353721

Posthumus, Michael; September, Alison V; Schwellnus, Martin P; Collins, Malcolm

2008-03-19

362

Valproic acid induces functional heat shock protein 70 via Class I histone deacetylase inhibition in cortical neurons: a potential role of Sp1 acetylation  

PubMed Central

Neuroprotective properties of the mood stabilizer valproic acid (VPA) are implicated in its therapeutic efficacy. Heat shock protein 70 (HSP70) is a molecular chaperone, neuroprotective and anti-inflammatory agent. The present study aimed to investigate underlying mechanisms and functional significance of HSP70 induction by VPA in rat cortical neurons. VPA treatment markedly upregulated HSP70 protein levels, and this was accompanied by increased HSP70 mRNA levels and promoter hyperacetylation and activity. Other HDAC inhibitors - sodium butyrate, trichostatin A and Class I HDAC-specific inhibitors MS-275 and apicidin, - all mimicked the ability of VPA to induce HSP70. Pretreatment with PI3-kinase inhibitors or an Akt inhibitor attenuated HSP70 induction by VPA and other HDAC inhibitors. VPA treatment increased Sp1 acetylation, and a Sp1 inhibitor, mithramycin, abolished the induction of HSP70 by HDAC inhibitors. Moreover, VPA promoted the association of Sp1 with the histone acetyltransferases p300 and recruitment of p300 to the HSP70 promoter. Further, VPA-induced neuroprotection against glutamate excitotoxicity was prevented by blocking HSP70 induction. Taken together, the data suggest that the PI3-kinase/Akt pathway and Sp1 are likely involved in HSP70 induction by HDAC inhibitors, and induction of HSP70 by VPA in cortical neurons may contribute to its neuroprotective and therapeutic effects.

Marinova, Zoya; Ren, Ming; Wendland, Jens R.; Leng, Yan; Liang, Min-Huei; Yasuda, Shigeru; Leeds, Peter; Chuang, De-Maw

2009-01-01

363

Child's Play: Revisiting Play in Early Childhood Settings.  

ERIC Educational Resources Information Center

|Noting that play is an essential aspect of learning for young children, this book presents a collection of articles on children's play in Australia. Part 1, "Play, Development, and Learning," contains the following chapters: (1) "The Role of Play in Development and Learning" (Ann Glover); (2) "Stop, Look, and Listen: Adopting an Investigative…

Dau, Elizabeth, Ed.; Jones, Elizabeth, Ed.

364

Play Therapist's Perspectives on Culturally Sensitive Play Therapy  

Microsoft Academic Search

The Association for Play Therapy (2009) promotes play therapists’ awareness of personal cultural identity, obtaining continuous cultural knowledge, and displaying culturally appropriate practices. Play therapy research includes studies on working with specific culturally diverse populations. Founding play therapists, such as Virginia Axline, have made suggestions for toys that should be included in the therapist’s playroom. This exploratory survey inquired about

Krystal M Vaughn

2012-01-01

365

Doxorubicin promotes transcriptional upregulation of Cdc25B in cancer cells by releasing Sp1 from the promoter.  

PubMed

Cdc25B phosphatases have a key role in G2/M cell-cycle progression by activating the CDK1-cyclinB1 complexes and functioning as important targets of checkpoints. Overexpression of Cdc25B results in a bypass of the G2/M checkpoint and illegitimate entry into mitosis. It can also cause replicative stress, which leads to genomic instability. Thus, fine-tuning of the Cdc25B expression level is critical for correct cell-cycle arrest in response to DNA damage. In response to genotoxic stress, Cdc25B is mainly regulated by post-transcriptional mechanisms affecting either Cdc25B protein stability or translation. Here, we show that upon DNA damage Cdc25B can be regulated at the transcriptional level. Although ionizing radiation downregulates Cdc25B in a p53-dependent pathway, doxorubicin transcriptionally upregulates Cdc25B in p53-proficient cancer cells. We show that in the presence of wild-type p53, doxorubicin activates the Cdc25B promoter by preventing the binding of Sp1 and increasing the binding of NF-Y on the Cdc25B promoter, thus preventing p53 from downregulating this promoter. Our results highlight the mechanistically distinct regulation of the three Cdc25 phosphatases by checkpoint signalling following doxorubicin treatment. PMID:23160377

Dalvai, M; Mondesert, O; Bugler, B; Manenti, S; Ducommun, B; Dozier, C

2012-11-19

366

The Child's Right To Play.  

ERIC Educational Resources Information Center

|This paper argues that play is an important and fundamental educational process and that the child's right to play should be respected. The paper also comments on the 1990 Tokyo International Conference on the Child's Right to Play. Several issues related to children's play, both in and out of school, are discussed. The focus is on the state of…

Morris, Beverley

367

Play in evolution and development  

Microsoft Academic Search

In this paper we examine the role of play in human ontogeny and phylogeny, following Surplus Resource Theory. We consider how juveniles use play to sample their environment in order to develop adaptive behaviors. We speculate about how innovative behaviors developed in play in response to environmental novelty may influence subsequent evolutionary processes. Play during this period of immaturity is

Anthony D. Pellegrini; Danielle Dupuis; Peter K. Smith

2007-01-01

368

Play Therapy in Elementary Schools  

ERIC Educational Resources Information Center

|Because the child's world is a world of action and activity, play therapy provides the psychologist in elementary-school settings with an opportunity to enter the child's world. In the play therapy relationship, toys are like the child's words and play is the child's language. Therefore, children play out their problems, experiences, concerns,…

Landreth, Garry L.; Ray, Dee C.; Bratton, Sue C.

2009-01-01

369

Playful Learning and Montessori Education  

ERIC Educational Resources Information Center

Although Montessori education is often considered a form of playful learning, Maria Montessori herself spoke negatively about a major component of playful learning--pretend play, or fantasy--for young children. In this essay, the author discusses this apparent contradiction: how and why Montessori education includes elements of playful learning…

Lillard, Angeline S.

2013-01-01

370

Music Learning and Child's Play.  

ERIC Educational Resources Information Center

|Reviews various studies on childs play and its relation to young childrens development in music learning processes and explores the role that cognitive and social play categories have in studying childrens play with music. Provides strategies for initiating music-play opportunities in a preschool classroom. (CMK)|

Littleton, Danette

1998-01-01

371

Non-Redundant Selector and Growth-Promoting Functions of Two Sister Genes, buttonhead and Sp1, in Drosophila Leg Development  

Microsoft Academic Search

The radically distinct morphologies of arthropod and tetrapod legs argue that these appendages do not share a common evolutionary origin. Yet, despite dramatic differences in morphology, it has been known for some time that transcription factors encoded by the Distalless (Dll)\\/Dlx gene family play a critical role in the development of both structures. Here we show that a second transcription

Carlos Estella; Richard S. Mann

2010-01-01

372

Toy Play, Play Tempo, and Reaction to Frustration in Infants.  

ERIC Educational Resources Information Center

In two sessions, the duration and tempo of toy play of infants and reaction of frustration were measured. Correlations indicated a general relationship between response persistence during play and attempts to escape frustrating situations. (Author/CM)

Longo, Josephine; And Others

1982-01-01

373

Urokinase induces stromal cell-derived factor-1 expression in human hepatocellular carcinoma cells.  

PubMed

Both the urokinase-type plasminogen activator (uPA) and the uPA receptor (uPAR) play important roles with regard to hepatocellular carcinoma (HCC) progression and metastasis. Notably, the stromal cell-derived factor-1 (SDF-1) is an important chemokine involved in HCC pathology. However, the influence of uPA on SDF-1 expression in human HCC cells remains unknown. We investigated the mechanisms underlying the modulation of SDF-1 expression through uPA stimulation in human HCC SK-Hep-1 cells. SK-Hep-1 cells stimulation with uPA induced increases in the expression and secretion of SDF-1. By using specific inhibitors and small interfering RNA, we have demonstrated that the activation of extracellular signal-related kinase (ERK) and c-Jun-NH(2)-terminal kinase (JNK) pathways are critical for uPA-induced SDF-1 expression. Transcription factor ELISA and chromatin immunoprecipitation assays suggest that uPA increase Sp1- and AP-1-DNA-binding activities in SK-Hep-1 cells. Inhibition of Sp1 and AP-1 activations by specific siRNAs blocked the uPA-induced SDF-1 promoter activity and expression. The effect of uPA on SK-Hep-1 signaling and SDF-1 expression is mediated by uPAR. In summary, our findings serve to elucidate the uPA/uPAR downstream signaling, providing new insight into the function of uPA in HCC cells. PMID:21465475

Hsu, Wen-Hsiu; Chen, Cheng-Nan; Huang, Hai-I; Lai, Yi-Liang; Teng, Chun-Yuh; Kuo, Wu-Hsien

2012-02-01

374

Spongiibacter marinus gen. nov., sp. nov., a halophilic marine bacterium isolated from the boreal sponge Haliclona sp. 1.  

PubMed

Strain HAL40b(T) was isolated from the marine sponge Haliclona sp. 1 collected at the Sula Ridge off the Norwegian coast and characterized by physiological, biochemical and phylogenetic analyses. The isolate was a small rod with a polar flagellum. It was aerobic, Gram-negative and oxidase- and catalase-positive. Optimal growth was observed at 20-30 degrees C, pH 7-9 and in 3 % NaCl. Substrate utilization tests were positive for arabinose, Tween 40 and Tween 80. Enzyme tests were positive for alkaline phosphatase, esterase lipase (C8), leucine arylamidase, acid phosphatase, naphthol-AS-BI-phosphohydrolase and N-acetyl-beta-glucosaminidase. The predominant cellular fatty acid was C(17 : 1) omega8, followed by C(17 : 0) and C(18 : 1) omega7. Analysis by matrix-assisted laser desorption/ionization time-of-flight MS was used to characterize the strain, producing a characteristic low-molecular-mass protein pattern that could be used as a fingerprint for identification of members of this species. The DNA G+C content was 69.1 mol%. Phylogenetic analysis supported by 16S rRNA gene sequence comparison classified the strain as a member of the class Gammaproteobacteria. Strain HAL40b(T) was only distantly related to other marine bacteria including Neptunomonas naphthovorans and Marinobacter daepoensis (type strain sequence similarity >90 %). Based on its phenotypic, physiological and phylogenetic characteristics, it is proposed that the strain should be placed into a new genus as a representative of a novel species, Spongiibacter marinus gen. nov., sp. nov.; the type strain of Spongiibacter marinus is HAL40b(T) (=DSM 17750(T) =CCUG 54896(T)). PMID:18319460

Graeber, Ingeborg; Kaesler, Ines; Borchert, Martin S; Dieckmann, Ralf; Pape, Thomas; Lurz, Rudi; Nielsen, Preben; von Döhren, Hans; Michaelis, Walter; Szewzyk, Ulrich

2008-03-01

375

Challenging Notions of Gendered Game Play: Teenagers playing The Sims  

Microsoft Academic Search

This paper challenges notions of gendered game playing practice implicit in much research into young women's involvement with the computer gaming culture. It draws on a study of Australian teenagers playing The Sims Deluxe as part of an English curriculum unit and insights from feminist media studies to explore relationships between gender and game playing practices. Departing from a reliance

Catherine Beavis; Claire Charles

2005-01-01

376

The Play's the Thing. Teachers' Roles in Children's Play.  

ERIC Educational Resources Information Center

The traditional role for teachers in children's play was to structure it, setting rules and interrupting if things got "out of hand." However, for children ages 3 to 5, sociodramatic play is a way to invent and make familiar the rhythms and actions of everyday life. This book describes why play is a fundamentally important part of children's…

Jones, Elizabeth; Reynolds, Gretchen

377

Sex Disparities in the Quality of Diabetes Care: Biological and Cultural Factors May Play a Different Role for Different Outcomes: A cross-sectional observational study from the AMD Annals initiative.  

PubMed

OBJECTIVE To investigate the quality of type 2 diabetes care according to sex. RESEARCH DESIGN AND METHODS Clinical data collected during the year 2009 were extracted from electronic medical records; quality-of-care indicators were evaluated. Multilevel logistic regression analysis was applied to estimate the likelihood of women versus men to be monitored for selected parameters, to reach clinical outcomes, and to be treated with specific classes of drugs. The intercenter variability in the proportion of men and women achieving the targets was also investigated. RESULTS Overall, 415,294 patients from 236 diabetes outpatient centers were evaluated, of whom 188,125 (45.3%) were women and 227,169 (54.7%) were men. Women were 14% more likely than men to have HbA1c >9.0% in spite of insulin treatment (odds ratio 1.14 [95% CI 1.10-1.17]), 42% more likely to have LDL cholesterol (LDL-C) ?130 mg/dL (1.42 [1.38-1.46]) in spite of lipid-lowering treatment, and 50% more likely to have BMI ?30 kg/m(2) (1.50 [1.50-1.54]). Women were less likely to be monitored for foot and eye complications. In 99% of centers, the percentage of men reaching the LDL-C target was higher than in women, the proportion of patients reaching the HbA1c target was in favor of men in 80% of the centers, and no differences emerged for blood pressure. CONCLUSIONS Women show a poorer quality of diabetes care than men. The attainment of the LDL-C target seems to be mainly related to pathophysiological factors, whereas patient and physician attitudes can play an important role in other process measures and outcomes. PMID:23835692

Rossi, Maria Chiara; Cristofaro, Maria Rosaria; Gentile, Sandro; Lucisano, Giuseppe; Manicardi, Valeria; Mulas, Maria Franca; Napoli, Angela; Nicolucci, Antonio; Pellegrini, Fabio; Suraci, Concetta; Giorda, Carlo

2013-07-08

378

Transcriptional regulation of the hepatocyte growth factor (HGF) gene by the Sp family of transcription factors.  

PubMed

In this study, we have localized an enhancer element in the 5'-flanking region of the HGF gene promoter and have identified its functional transcriptional factors. Through transient transfection of NIH3T3 fibroblast cells and gel mobility shift assays, the functional binding site was localized to a short region (-318 to -303 bp from the transcription start site) which has a CTCCC sequence. This motif is also conserved in the human HGF promoter and acts as a binding site for the Sp family of transcription factors. In the presence of NIH3T3 nuclear protein extracts, this enhancer region formed specific DNA-protein complexes which were totally abrogated by excess amounts of consensus Sp1 oligonucleotide. In gel mobility supershift assays, anti-Sp1 and anti-Sp3 antibodies specifically recognized these complexes as was evident by their slower migration. Site-specific mutation of this binding motif resulted in total loss of Sp1 and Sp3 binding and a concomitant loss of enhancer function within the context of the HGF promoter. Furthermore, in transient cotransfection assays, overexpression of Sp1 and/or Sp3 stimulated HGF promoter activity independently and additively through binding to the Sp1 binding site in the HGF gene promoter region. DNaseI hypersensitive analysis of freshly isolated nuclei from NIH3T3 cells revealed that five hypersensitive sites (HSS) are present within the 2 kb region immediately upstream of the HGF promoter. One of these sites was mapped to position -0.3 kb from the transcription start site. These data show that both Sp1 and Sp3 transcription factors upregulate HGF promoter activity by binding to the Sp1 binding site at position -318 to -303 bp in the HGF gene promoter. PMID:9223667

Jiang, J G; Chen, Q; Bell, A; Zarnegar, R

1997-06-26

379

Mathematical Adventures in Role Play  

ERIC Educational Resources Information Center

The provision of role play is vital in every early years setting. It provides opportunities for the development of all areas of learning. With careful thought and planning, all role play situations can provide children with mathematical adventures. Many examples of good quality role play had been observed in a variety of settings throughout…

Tyce, Constance

2002-01-01

380

Play in Evolution and Development  

ERIC Educational Resources Information Center

|In this paper we examine the role of play in human ontogeny and phylogeny, following Surplus Resource Theory. We consider how juveniles use play to sample their environment in order to develop adaptive behaviors. We speculate about how innovative behaviors developed in play in response to environmental novelty may influence subsequent…

Pellegrini, Anthony D.; Dupuis, Danielle; Smith, Peter K.

2007-01-01

381

The Biology of Human Play.  

ERIC Educational Resources Information Center

|Maintains that the "getting into shape" hypothesis of explaining the inverted-U distribution of exercise play across age is likely incorrect. Argues that the biological study of human physical activity play, as recommended by Pellegrini and Smith (1998), will reveal whether physical activity play represents an example of performance-dependent…

Byers, John A.

1998-01-01

382

An Sp1 binding site involves the transcription of the fas ligand gene induced by PMA and ionomycin in Jurkat cells  

Microsoft Academic Search

The transcriptional regulation of the Fas ligand (FasL) gene in Jurkat cells was investigated. We demonstrated that an Sp1 binding site, located between ?280 and ?275 bp relative to the translational start site (+1) of the FasL gene, was important for the transcription of the FasL gene by deletion and mutation analysis in Jurkat cells after phorbol 12-myristate 13-acetate (PMA)

Chun-Fen Chou; Hong-Wen Peng; Chung-Yih Wang; Ya-Ting Yang; Shou-Hwa Han

2000-01-01

383

Playing Safe: Eliminating Hazards on Children's Playgrounds.  

ERIC Educational Resources Information Center

Discusses typical playground hazards, environmental factors affecting safety in play areas, playground safety guidelines and standards established by the Consumer Product Safety Commission and the American Society of Testing Materials, and playground surfacing and equipment. Offers suggestions for reducing the number and severity of playground…

Wallach, Frances

1992-01-01

384

Epigenetic regulation of human ?1d-adrenergic receptor gene expression: a role for DNA methylation in Sp1-dependent regulation  

PubMed Central

A growing body of evidence implicates ?1-adrenergic receptors (?1ARs) as potent regulators of growth pathways. The three ?1AR subtypes (?1aAR, ?1bAR, ?1dAR) display highly restricted tissue expression that undergoes subtype switching with many pathological stimuli, the mechanistic basis of which remains unknown. To gain insight into transcriptional pathways governing cell-specific regulation of the human ?1dAR subtype, we cloned and characterized the ?1dAR promoter region in two human cellular models that display disparate levels of endogenous ?1dAR expression (SK-N-MC and DU145). Results reveal that ?1dAR basal expression is regulated by Sp1-dependent binding of two promoter-proximal GC boxes, the mutation of which attenuates ?1dAR promoter activity 10-fold. Mechanistically, chromatin immunoprecipitation data demonstrate that Sp1 binding correlates with expression of the endogenous gene in vivo, correlating highly with ?1dAR promoter methylation-dependent silencing of both episomally expressed reporter constructs and the endogenous gene. Further, analysis of methylation status of proximal GC boxes using sodium bisulfite sequencing reveals differential methylation of proximal GC boxes in the two cell lines examined. Together, the data support a mechanism of methylation-dependent disruption of Sp1 binding in a cell-specific manner resulting in repression of basal ?1dAR expression.

Michelotti, Gregory A.; Brinkley, D. Marshall; Morris, Daniel P.; Smith, Michael P.; Louie, Raphael J.; Schwinn, Debra A.

2008-01-01

385

Membrane-Type 1 Matrix Metalloproteinase Is Regulated by Sp1 through the Differential Activation of AKT, JNK, and ERK Pathways in Human Prostate Tumor Cells1  

PubMed Central

We and other investigators have previously shown that membrane-type 1 matrix metalloproteinase (MT1-MMP) is overexpressed in invasive prostate cancer cells. However, the mechanism for this expression is not known. Here, we show that MT1-MMP is minimally expressed in nonmalignant primary prostate cells, moderately expressed in DU-145 cells, and highly expressed in invasive PC-3 and PC-3N cells. Using human MT1-MMP promoter reporter plasmids and mobility shift assays, we show that Sp1 regulates MT1-MMP expression in DU-145, PC-3, and PC-3N cells and in PC3-N cells using chromatin immunoprecipitation analysis and silencing RNA. Investigation of signaling pathway showed that DU-145 cells express constitutively phosphorylated extracellular stress-regulated kinase (ERK), whereas PC-3 and PC-3N cells express constitutively phosphorylated AKT/PKB and c-Jun NH2 terminal kinase (JNK). We show that MT1-MMP and Sp1 levels are decreased in PC-3 and PC-3N cells when phosphatidylinositol-3 kinase and JNK are inhibited, and that MT1-MMP levels are decreased in DU-145 cells when MEK is inhibited. Transient transfection of PC-3 and PC-3N cells with a dominant-negative JNK or p85, and of DU-145 cells with a dominant negative ERK, reduces MT1-MMP promoter activity. These results indicate differential signaling control of Sp1-mediated transcriptional regulation of MT1-MMP in prostate cancer cell lines.

Sroka, Isis C; Nagle, Raymond B; Bowden, G Tim

2007-01-01

386

Stability of playfulness across environmental settings: a pilot study.  

PubMed

The Test of Playfulness (ToP) was used in this pilot study to examine the stability of playfulness of 16 children with cerebral palsy (CP), aged 4-8 years, across three environmental settings: home, community, and school. Each videotaped play segment was scored using the ToP. The ANOVA statistic demonstrated a significant variance (p < 0.05) in the playfulness of the children across the 3 settings. The children were most playful at home and least playful at school (p < 0.05). The variability in playfulness across settings suggests that playful behaviors are influenced by factors external to the child. Eleven children were playful (achieving a positive ToP score) in at least one environment, which demonstrates that they had the capacity to be playful. Their play was supported in some settings and not in others. However, there was a lack of playfulness in 65% of the play segments suggesting that these children experience many barriers to their participation in play. Future research is needed to identify factors that help and hinder the playfulness of children with CP. PMID:17298939

Rigby, Patricia; Gaik, Sandy

2007-01-01

387

A Profile of Children's Play in Urban India.  

ERIC Educational Resources Information Center

Observed universal and culturally specific features of play conditioned by ecological factors, social class, and gender in India. Found that, although ecological constraints conspired against the urban child's natural propensity to play with joyous spontaneity, there were also conscious community endeavors to create play environments. Children…

Oke, Meera; Khattar, Archna; Pant, Prarthana; Saraswathi, T. S.

1999-01-01

388

Playing with toys: Towards autonomous robot manipulation for therapeutic play  

Microsoft Academic Search

When young children play, they often manipulate toys that have been specifically designed to accommodate and stimulate their perceptual-motor skills. Robotic playmates capable of physically manipulating toys have the potential to engage children in therapeutic play and augment the beneficial interactions provided by overtaxed care givers and costly therapists. To date, assistive robots for children have almost exclusively focused on

Alexander J. B. Trevor; Hae Won Park; Ayanna M. Howard; Charles C. Kemp

2009-01-01

389

Taking Play Home: Encouraging Parents To Encourage Play.  

ERIC Educational Resources Information Center

Discusses data from surveys assessing parents feelings about their children's play, finding that while parents believe play is important for children's development, they often believe that early academic learning is more important. Offers suggestions for early childhood educators to help parents make playtime more available to their children. (EV)

Oliver, Susan J.; Klugman, Edgar

2003-01-01

390

Integrating play in neurodevelopmental treatment.  

PubMed

This article presents one perspective on the integration of play activities within a neurodevelopmental frame of reference. Based on the premise that activities are characteristic of occupational therapy intervention, issues related to combining play activities with neurodevelopmental principles are discussed. Clinical examples are also provided to illustrate the value of integrating play activities within the occupational therapy treatment of the child with cerebral palsy. PMID:3688158

Anderson, J; Hinojosa, J; Strauch, C

1987-07-01

391

Conserved POU-binding site linked to SP1-binding site within FZD5 promoter: Transcriptional mechanisms of FZD5 in undifferentiated human ES cells, fetal liver/spleen, adult colon, pancreatic islet, and diffuse-type gastric cancer.  

PubMed

Canonical WNT signals are transduced through Frizzled (FZD) family receptor and LRP5/LRP6 co-receptor to upregulate FGF20, JAG1, DKK1, WISP1, CCND1 and MYC genes for cell-fate determination, while non-canonical WNT signals are transduced through FZD family receptor and ROR2/PTK7/RYK co-receptor to activate RHOA/RHOU/RAC/CDC42, JNK, PKC, NLK and NFAT signaling cascades for the regulation of tissue polarity, cell movement, and adhesion. We previously reported molecular cloning and characterization of human FZD5, which showed six amino-acid substitutions with human Hfz5. FZD5, functioning as WNT5A receptor, is the key molecule in the fields of oncology, regenerative medicine, cardiology, rheumatology, diabetology, and gastroenterology. Here, comparative integromics analyses on FZD5 orthologs were performed by using bioinformatics (Techint) and human intelligence (Humint). Chimpanzee FZD5 and cow Fzd5 genes were identified within NW_104292.1 and AC166656.2 genome sequences, respectively. FZD5 orthologs were seven-transmembrane proteins with extracellular Frizzled domain, leucine zipper motif around the 5th transmembrane domain, and cytoplasmic DVL- and PDZ-binding motifs. Ser523 and Ser529 around the DVL-binding motif of FZD5 orthologs were putative aPKC phosphorylation sites. POU5F1 (OCT4)-binding site linked to SP1-binding site within the 5'-promoter region of human FZD5 gene was evolutionarily conserved among mammalian FZD5 orthologs. POU5F1 was more related to POU2F and POU3F subfamily members. POU5F1 was preferentially expressed in undifferentiated human embryonic stem (ES) cells, pancreatic islet, and diffuse-type gastric cancer. POU2F1 (OCT1) was expressed in ES cells, fetal liver/spleen, adult colon, POU2F2 in ES cells, fetal liver/spleen, and POU2F3 in diffuse-type gastric cancer. Multiple SP1/KLF family members, other than KLF2 or KLF4, were expressed in undifferentiated human ES cells. Together, these facts indicate that POU5F1 and POU2F subfamily members play a pivotal role for the FZD5 expression in undifferentiated human ES cells, fetal liver/spleen, adult colon, pancreatic islet, and diffuse-type gastric cancer. PMID:17273778

Katoh, Yuriko; Katoh, Masaru

2007-03-01