Cell-Specific Regulation of IRS-1 Gene Expression: Role of E Box and C/EBP Binding Site in HepG2 Cells and CHO Cells

Diabetes ◽  
1997 ◽  
Vol 46 (3) ◽  
pp. 354-362 ◽  
Author(s):  
K. Matsuda ◽  
E. Araki ◽  
R. Yoshimura ◽  
K. Tsuruzoe ◽  
N. Furukawa ◽  
...  
Keyword(s):  
Gene Expression ◽  
Binding Site ◽  
Cho Cells ◽  
Hepg2 Cells ◽  
E Box ◽  
Specific Regulation

Cell-specific regulation of IRS-1 gene expression: role of E box and C/EBP binding site in HepG2 cells and CHO cells

Diabetes ◽  
1997 ◽  
Vol 46 (3) ◽  
pp. 354-362 ◽  
Author(s):  
K. Matsuda ◽  
E. Araki ◽  
R. Yoshimura ◽  
K. Tsuruzoe ◽  
N. Furukawa ◽  
...  
Keyword(s):  
Gene Expression ◽  
Binding Site ◽  
Cho Cells ◽  
Hepg2 Cells ◽  
E Box ◽  
Specific Regulation

The role of NeuroD1 in the upregulation of SMYD3 by HBx.

2012 ◽  
Vol 30 (4_suppl) ◽  
pp. 183-183
Author(s):  
Junyao Xu ◽  
Qingqi Hong ◽  
Chuanchao He ◽  
Jie Wang
Keyword(s):  
Gene Expression ◽  
Binding Site ◽  
Promoter Region ◽  
Gene Transfection ◽  
Histone Methyltransferase ◽  
Proximal Promoter ◽  
Luciferase Reporter ◽  
Mobility Shift ◽  
Cis Element ◽  
E Box

183 Background: SET and MYND Domain-Containing Protein 3 (SMYD3) is frequently overexpressed in hepatocellular carcinoma (HCC) exhibiting increased malignant phenotypes. It has also been known that the hepatitis B virus x protein (HBx) is strongly associated with HCC development and progression. Although overexpression of both proteins is related to HCC, the relationship between the two has not been well studied. Methods: Immunohistochemical staining was used to detect the expression of HBx and SMYD3 in HCC tumor tissues. HBx gene transfection, RNAi, and histone methyltransferase(H3-K4) activity assay were performed to reveal the transcrpitionally activation of HBx on functional SMYD3 gene expression. Chromatin immunoprecipitation (ChIP), Co-immunoprecipitation (Co-IP), Electrophoretic mobility shift assay (EMSA) were applied to investigate the underlying mechanism. Dual-luciferase reporter assay was used to search for the HBx responsive cis-element of SMYD3 gene. Results: Immunohistochemistry identified the positive correlation between HBx and SMYD3 expression in 42 HCC tissues. Up-regulation of HBx on SMYD3 expression was validated through experiments involving overexpression or knock-down of HBx in different HCC cell lines. And up-regulated SMYD3 is functionally active as histone methyltransferase. Next we found that HBx transcriptionally regulated SMYD3 gene expression by interacting with RNA polymerase IIand altering its binding site to a proximal promoter region(SD2) from a distant promoter region(SD6) of SMYD3. Truncated and mutant reporter assays revealed that the cis-element mapped in -178~-203bp in SMYD3 promotor is responsive for HBx-transactivation. And this 25bp cis-element contains a E-box 3 unit, which is a binding site for the transcriptional factor Neurogenic differentiation 1(NeuroD1). EMSA and Chip showed that HBx increased NeuroD1 binding to SMYD3 proximal promotor, however transcient expression of antisense NeuroD1 abolished HBx-induced SMYD3 expression. Conclusions: HBx transcriptionally up-regulates SMYD3 and that this process is mediated by NeuroD1 through binding to the E-box 3 site of SMYD3 promotor.

scholarly journals Regulation of the Human Secretin Gene Is Controlled by the Combined Effects of CpG Methylation, Sp1/Sp3 Ratio, and the E-Box Element

2004 ◽  
Vol 18 (7) ◽  
pp. 1740-1755 ◽  
Author(s):  
Leo Tsz-On Lee ◽  
Kian-Cheng Tan-Un ◽  
Ronald Ting-Kai Pang ◽  
David Tai-Wai Lam ◽  
Billy Kwok-Chong Chow
Keyword(s):  
Gene Expression ◽  
Hepg2 Cells ◽  
Cpg Island ◽  
Methylation Status ◽  
Gene Promoter ◽  
Mobility Shift ◽  
Specific Pcr ◽  
E Box

Abstract To unravel the mechanisms that regulate the human secretin gene expression, in this study, we have used secretin-expressing (HuTu-80 cells, human duodenal adenocarcinoma) and non-secretin-expressing [PANC-1 (human pancreatic ductile carcinoma) and HepG2 (human hepatocellular carcinoma) cells] cell models for in vitro and in vivo analyses. By transient transfection assays, within the promoter region (−11 to −341 from ATG, relative to the ATG initiation codon), we have initially identified several functional motifs including an E-box and 2 GC-boxes. Results from gel mobility shift and chromatin immunoprecipitation assays confirmed further that NeuroD, E2A, Sp1, and Sp3 bind to these E- and GC-boxes in HuTu-80 cells in vitro and in vivo, whereas only high levels of Sp3 is observed to bind the promoter in HepG2 cells. In addition, overexpression of Sp3 resulted in a dose-dependent repression of the Sp1-mediated transactivation. Collectively, these data suggest that the Sp1/Sp3 ratio is instrumental to controlling secretin gene expression in secretin-producing and non-secretin-producing cells. The functions of GC-box and Sp proteins prompted us to investigate the possible involvement of DNA methylation in regulating this gene. Consistent with this idea, we found a putative CpG island (−336 to 262 from ATG) that overlaps with the human secretin gene promoter. By methylation-specific PCR, all the CpG dinucleo-tides (26 of them) within the CpG island in HuTu-80 cells are unmethylated, whereas all these sites are methylated in PANC-1 and HepG2 cells. The expressions of secretin in PANC-1 and HepG2 cells were subsequently found to be significantly activated by a demethylation agent, 5′-Aza-2′ deoxycytidine. Taken together, our data indicate that the human secretin gene is controlled by the in vivo Sp1/Sp3 ratio and the methylation status of the promoter.

scholarly journals Role of the GATA-1/FOG-1/NuRD Pathway in the Expression of Human β-Like Globin Genes

2010 ◽  
Vol 30 (14) ◽  
pp. 3460-3470 ◽  
Author(s):  
Annarita Miccio ◽  
Gerd A. Blobel
Keyword(s):  
Gene Expression ◽  
Molecular Mechanisms ◽  
Globin Gene ◽  
Globin Genes ◽  
Nurd Complex ◽  
Adult Type ◽  
Specific Regulation ◽  
Globin Gene Expression

ABSTRACT The human β-globin genes are expressed in a developmentally controlled fashion. Studies on the molecular mechanisms underlying the stage-specific regulation of globin genes have been fueled by the clinical benefit of elevated fetal γ-globin expression in patients with sickle cell anemia and thalassemia. Recent reports suggested a role of the hematopoietic transcription factor GATA-1, its cofactor FOG-1, and the associated chromatin remodeling complex NuRD in the developmental silencing of HBG1 and HBG2 gene expression. To examine whether FOG-1 via NuRD controls HBG1 and HBG2 silencing in vivo, we created mice in which the FOG-1/NuRD complex is disrupted (A. Miccio et al., EMBO J. 29:442-456, 2010) and crossed these with animals carrying the entire human β-globin gene locus as a transgene. We found that the FOG-1/NuRD interaction is dispensable for the silencing of human HBG1 and HBG2 expression. In addition, mutant animals displayed normal silencing of the endogenous embryonic globin genes. In contrast, a significant reduction of adult-type human and murine globin gene expression was found in adult bone marrows of mutant animals. These results suggest that, unexpectedly, NuRD is required for FOG-1-dependent activation of adult-type globin gene expression but is dispensable for human γ-globin silencing in vivo.

MyoD promotes porcine PPARγ gene expression through an E-box and a MyoD-binding site in the PPARγ promoter region

2016 ◽  
Vol 365 (2) ◽  
pp. 381-391 ◽  
Author(s):  
Bing Deng ◽  
Feng Zhang ◽  
Kun Chen ◽  
Jianghui Wen ◽  
Haijun Huang ◽  
...  
Keyword(s):  
Gene Expression ◽  
Binding Site ◽  
Promoter Region ◽  
E Box ◽  
Pparγ Gene

scholarly journals Reduced SCD1 activity alters markers of fatty acid reesterification, glyceroneogenesis, and lipolysis in murine white adipose tissue and 3T3-L1 adipocytes

2017 ◽  
Vol 313 (3) ◽  
pp. C295-C304 ◽  
Author(s):  
Steven M. Dragos ◽  
Karl F. Bergeron ◽  
Frédérik Desmarais ◽  
Katherine Suitor ◽  
David C. Wright ◽  
...  
Keyword(s):  
Gene Expression ◽  
Adipose Tissue ◽  
Fatty Acid ◽  
White Adipose Tissue ◽  
Phosphoenolpyruvate Carboxykinase ◽  
Critical Role ◽  
Wild Type ◽  
Important Regulator ◽  
Specific Regulation

White adipose tissue (WAT) has a critical role in lipid handling. Previous work demonstrated that SCD1 is an important regulator of WAT fatty acid (FA) composition; however, its influence on the various interconnected pathways influencing WAT lipid handling remains unclear. Our objective was to investigate the role of SCD1 on WAT lipid handling using Scd1 knockout (KO) mice and SCD1-inhibited 3T3-L1 adipocytes by measuring gene, protein, and metabolite markers related to FA reesterification, glyceroneogenesis, and lipolysis. Triacylglycerol (TAG) content was higher in inguinal WAT (iWAT) from KO mice compared with wild-type, but significantly lower in epididymal WAT (eWAT). The SCD1 desaturation index was decreased in both WAT depots in KO mice. FA reesterification, as measured with a NEFA:glycerol ratio, was reduced in both WAT depots in KO mice, as well as SCD1-inhibited 3T3-L1 adipocytes. Pck1, Atgl, and Hsl gene expression was reduced in both WAT depots of KO mice, while Pck2 and Pdk4 gene expression showed depot-specific regulation. Pck1, Atgl, and Hsl gene expression was reduced, and phosphoenolpyruvate carboxykinase protein content was ablated, in SCD1-inhibited adipocytes. Our data provide evidence that SCD1 has a broad impact on WAT lipid handling by altering TAG composition in a depot-specific manner, reducing FA reesterification, and regulating markers of lipolysis and glyceroneogenesis.

scholarly journals Estrogen Enhances Gonadotropin-Releasing Hormone-Stimulated Transcription of the Luteinizing Hormone Subunit Promoters via Altered Expression of Stimulatory and Suppressive Transcription Factors

Endocrinology ◽  
2007 ◽  
Vol 148 (12) ◽  
pp. 6083-6091 ◽  
Author(s):  
Takanori Kowase ◽  
Heidi E. Walsh ◽  
Douglas S. Darling ◽  
Margaret A. Shupnik
Keyword(s):  
Gene Expression ◽  
Promoter Activity ◽  
Gonadotropin Releasing Hormone ◽  
Α Subunit ◽  
Altered Expression ◽  
E Box ◽  
17Β Estradiol ◽  
E Boxes ◽  
Stimulation Of

Transcription of the LH subunit genes is stimulated by GnRH and may be modulated physiologically by steroids such as 17β-estradiol (E). We found that E treatment amplified GnRH stimulation of the rat LHβ and α-subunit promoters, and expression of the endogenous mRNA, in LβT2 gonadotrope cells 2- to 5-fold above GnRH alone. We examined gene expression in LβT2 cells after E and/or GnRH treatment, and found that E suppressed expression of transcription factor Zfhx1a, and enhanced GnRH stimulation of Egr-1 mRNA and protein. E effects were abolished in the presence of antiestrogen. Egr-1 is critical for LHβ expression; however, the role of Zfhx1a, which binds to E-box sequences, was untested. We found E-box motifs in both the rat LHβ (−381, −182, and −15 bp) and α-subunit (−292, −64, −58 bp) promoters. Zfhx1a overexpression suppressed basal and GnRH-stimulated activity of both promoters. Mutation of the α-subunit promoter E boxes at either −64 or −58 bp eliminated Zfhx1a suppression, whereas mutation of the −292 bp E box had no effect. Gel shift assays demonstrated that Zfhx1a bound to the −64 and −58, but not −292, bp E-box DNA. Similarly, mutation of LHβ promoter E boxes at either −381 or −182, but not −15, bp reduced Zfhx1a suppression, correlating with binding of Zfhx1a. The −381 bp LHβ E box overlaps with an Sp1 binding site in the distal GnRH-stimulatory region, and increased Sp1 expression overcame Zfhx1a suppression. Thus, one mechanism by which E may enhance GnRH-stimulated LH subunit promoter activity is through regulation of both activators and suppressors of transcription.

scholarly journals On the Role of c-Jun in the Induction of PAI-1 Gene Expression by Phorbol Ester, Serum, and IL-1α in HepG2 Cells

1999 ◽  
Vol 19 (1) ◽  
pp. 39-46 ◽  
Author(s):  
Janine Arts ◽  
Jos Grimbergen ◽  
Karin Toet ◽  
Teake Kooistra
Keyword(s):  
Gene Expression ◽  
Phorbol Ester ◽  
Hepg2 Cells ◽  
Pai 1
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