scholarly journals Functional Analysis of Steroidogenic Factor 1 (sf-1) and 17α-Hydroxylase/Lyase (cyp17α) Promoters in Yellow Catfish Pelteobagrus fulvidraco

2020 ◽  
Vol 22 (1) ◽  
pp. 195
Author(s):  
Wu-Hong Lv ◽  
Guang-Hui Chen ◽  
Mei-Qin Zhuo ◽  
Yi-Huan Xu ◽  
Yi-Chuang Xu ◽  
...  
Keyword(s):  
Binding Sites ◽  
Promoter Activity ◽  
Pelteobagrus Fulvidraco ◽  
Peroxisome Proliferator ◽  
Yellow Catfish ◽  
Site Mutation ◽  
Promoter Regions ◽  
Mobility Shift ◽  
Peroxisome Proliferator Activated Receptor ◽  
Steroidogenic Factor 1

The present study was performed to clone and characterize the structures and functions of steroidogenic factor 1 (sf-1) and 17α-hydroxylase/lyase (cyp17α) promoters in yellow catfish Pelteobagrus fulvidraco, a widely distributed freshwater teleost. We successfully obtained 1981 and 2034 bp sequences of sf-1 and cyp17α promoters, and predicted the putative binding sites of several transcription factors, such as Peroxisome proliferator-activated receptor alpha (PPARα), Peroxisome proliferator-activated receptor gamma (PPARγ) and Signal transducer and activator of transcription 3 (STAT3), on sf-1 and cyp17α promoter regions, respectively. Overexpression of PPARγ significantly increased the activities of sf-1 and cyp17α promoters, but overexpression of PPARα significantly decreased the promoter activities of sf-1 and cyp17α. Overexpression of STAT3 reduced the activity of the sf-1 promoter but increased the activity of the cyp17α promoter. The analysis of site-mutation and electrophoretic mobility shift assay suggested that the sf-1 promoter possessed the STAT3 binding site, but did not the PPARα or PPARγ binding sites. In contrast, only the PPARγ site, not PPARα or STAT3 sites, was functional with the cyp17α promoter. Leptin significantly increased sf-1 promoter activity, but the mutation of STAT3 and PPARγ sites decreased leptin-induced activation of sf-1 promoter. Our findings offered the novel insights into the transcriptional regulation of sf-1 and cyp17α and suggested leptin regulated sf-1 promoter activity through STAT3 site in yellow catfish.

scholarly journals Molecular Characterization and Functional Analysis of Two Steroidogenic Genes TSPO and SMAD4 in Yellow Catfish

2021 ◽  
Vol 22 (9) ◽  
pp. 4505
Author(s):  
Fang Chen ◽  
Chong-Chao Zhong ◽  
Chang-Chun Song ◽  
Shu-Wei Chen ◽  
Yang He ◽  
...  
Keyword(s):  
Promoter Activity ◽  
Tissue Expression ◽  
Gonadal Development ◽  
Pelteobagrus Fulvidraco ◽  
The Novel ◽  
Yellow Catfish ◽  
Site Mutation ◽  
Promoter Regions ◽  
Promoter Sequences ◽  
Different Levels

The steroid hormones are required for gonadal development in fish. The present study was undertaken to characterize the cDNA and promoter sequences of TSPO and SMAD4 genes in yellow catfish Pelteobagrus fulvidraco, explored the mRNA tissue expression and deciphered their promoter regions. Yellow catfish TSPO and SMAD4 shared the similar domains to the corresponding genes from other vertebrates. The TSPO and SMAD4 mRNAs were widely expressed in the detected tissues, but at different levels. Several transcription factors were predicted, such as Sp, GATA, AP1, SOX1, SRY, STAT, HNF4α, PPARγ, Pu.1 and FOXL2. PPARγ overexpression increased but STAT3 overexpression reduced TSPO promoter activity, and FOXL2 overexpression inhibited the promoter activity of TSPO and SMAD4. The site mutation and EMSA analysis indicated that TSPO promoter possessed STAT3 and FOXL2 sites. Overall, our provided the novel understanding into the transcriptionally regulatory mechanisms of TSPO and SMAD4 in fish.

scholarly journals Novel Insights for PI3KC3 in Mediating Lipid Accumulation in Yellow Catfish Pelteobagrus Fulvidraco

2021 ◽  
Author(s):  
Mei-Qin Zhuo ◽  
Jun Chen ◽  
Mei-Li Wu ◽  
Wen-biao Wang
Keyword(s):  
Transcriptional Regulation ◽  
Protein Level ◽  
Lipid Accumulation ◽  
Mrna Level ◽  
Pelteobagrus Fulvidraco ◽  
Yellow Catfish ◽  
Site Mutation ◽  
Mobility Shift ◽  
Mobility Shift Assay ◽  
Mutation Assay

Abstract In this study, the transcriptional regulation of PI3KC3 by three transcript factors (PPARγ, PPARα and STAT3) and the potential role of PI3KC3 in mediating lipid accumulation were determined in yellow catfish Pelteobagrus fulvidraco. The 5’-deletion assay, overexpression assay, site-mutation assay and electrophoretic mobility shift assay suggested that PPARα, PPARγ and STAT3 negatively regulated the promoter activity of pi3kc3. Moreover, the transcriptional inactivation of pi3kc3 was directly mediated by PPARα and PPARγ under fatty acid (FA) treatment. Using primary hepatocytes from yellow catfish, FA incubation significantly increased triacylglyceride (TG), NEFA content, the mRNA level of pparα, pparγ, stat3 and dnmt3b, the protein level of PPARα, PPARγ and STAT3, and the methylation level of pi3kc3, but significantly reduced the mRNA and protein level of PI3KC3. Our findings offer new insights into the mechanisms for transcriptional regulation of PI3KC3 and for PI3KC3-mediated lipid accumulation in fish.

scholarly journals The effect of peroxisome-proliferator-activated receptor-α on the activity of the cholesterol 7α-hydroxylase gene

2000 ◽  
Vol 351 (3) ◽  
pp. 747-753 ◽  
Author(s):  
Dilip D. PATEL ◽  
Brian L. KNIGHT ◽  
Anne K. SOUTAR ◽  
Geoffrey F. GIBBONS ◽  
David P. WADE
Keyword(s):  
Binding Sites ◽  
Cholesterol Metabolism ◽  
Mrna Abundance ◽  
Major Influence ◽  
Dark Phase ◽  
Peroxisome Proliferator ◽  
Dependent Manner ◽  
Mobility Shift ◽  
Concentration Dependent Manner ◽  
Peroxisome Proliferator Activated Receptor

Cholesterol 7α-hydroxylase (Cyp7a1) plays a central role in the regulation of bile acid and cholesterol metabolism, and transcription of the gene is controlled by bile acids and hormones acting through a complex interaction with a number of potential steroid-hormone-binding sites. Transcriptional activity of the human CYP7A1 gene promoter transfected into HepG2 cells was decreased in a concentration-dependent manner by co-transfection with an expression vector for peroxisome-proliferator-activated receptor-α (PPARα). This effect was augmented by 9-cis-retinoic acid receptor-α (RXRα) and activators of PPARα to give a maximum inhibition of approx. 80%. The region responsible for this inhibition contained a site known to bind hepatocyte nuclear factor 4 (HNF4), and mutation of this site greatly decreased the effect. Co-expression of HNF4 increased promoter activity and decreased the effect of PPARα. Gel-mobility-shift assays failed to detect any binding of PPARα/RXRα dimers to any regions of the promoter containing potential binding sites. Also the hepatic abundance of Cyp7a1 mRNA in mice in which the PPARα gene was disrupted was the same as in normal mice, both during the dark phase, when the animals were feeding, and during the light phase, when mRNA abundance was greatly increased. Cholesterol feeding produced the same increase in hepatic Cyp7a1 mRNA abundance in PPARα-null animals as in normals. It is concluded that, whereas PPARα can affect CYP7A1 gene transcription in vitro through an indirect action, probably by competing for co-factors, this is unlikely to be a major influence on Cyp7a1 activity under normal physiological conditions.

scholarly journals Nano-Zn Increased Zn Accumulation and Triglyceride Content by Up-Regulating Lipogenesis in Freshwater Teleost, Yellow Catfish Pelteobagrus fulvidraco

2020 ◽  
Vol 21 (5) ◽  
pp. 1615 ◽  
Author(s):  
Shi-Cheng Ling ◽  
Mei-Qin Zhuo ◽  
Dian-Guang Zhang ◽  
Heng-Yang Cui ◽  
Zhi Luo
Keyword(s):  
Fatty Acid ◽  
Fatty Acid Synthase ◽  
Pelteobagrus Fulvidraco ◽  
Fatty Acid Transport ◽  
Peroxisome Proliferator ◽  
Mrna Levels ◽  
Yellow Catfish ◽  
Peroxisome Proliferator Activated Receptor ◽  
Lipogenic Genes ◽  
Zn Accumulation

The present study was conducted to explore the mechanism of nano-Zn absorption and its influence on lipid metabolism in the intestine of yellow catfish Pelteobagrus fulvidraco. Compared to ZnSO4, dietary nano-Zn addition increased the triglyceride (TG) content, enzymatic activities of malic enzyme (ME) and fatty acid synthase (FAS), and up-regulated mRNA levels of 6pgd, fas, acca, dgat1, pparγ, and fatp4. Using primary intestinal epithelial cells of yellow catfish, compared to the ZnSO4 group, nano-Zn incubation increased the contents of TG and free fatty acids (FFA), the activities of glucose-6-phosphate dehydrogenase (G6PD), 6-phosphogluconate dehydrogenase (6GPD), ME, and FAS, up-regulated mRNA levels of lipogenic genes (6pgd, g6pd, fas, dgat1, and pparγ), genes of lipid transport (fatp4 and ifabp), and Zn transport genes (znt5, znt7, mt, and mtf1), and increased the protein expression of fatty acid transport protein 4 (FATP4) and peroxisome proliferator activated receptor gamma (PPARγ). Further studies found that nano-Zn absorption was via the clathrin-dependent endocytic mechanism. PPARγ mediated the nano-Zn-induced increase in TG, and nano-Zn increased Zn accumulation and induced TG accumulation by activating the PPARγ pathway and up-regulating lipogenesis.

The DLK gene is a transcriptional target of PPARγ

2011 ◽  
Vol 438 (1) ◽  
pp. 93-101 ◽  
Author(s):  
Jean-Philippe Couture ◽  
Richard Blouin
Keyword(s):  
Transcriptional Activation ◽  
Binding Sites ◽  
Leucine Zipper ◽  
Transcriptional Start Site ◽  
Peroxisome Proliferator ◽  
Mobility Shift ◽  
Peroxisome Proliferator Activated Receptor ◽  
Bioinformatic Tools ◽  
Pparγ Agonist ◽  
Transcriptional Target

DLK (dual leucine zipper-bearing kinase) is a key regulator of development, cell differentiation and apoptosis. Interestingly, recent studies have shown that DLK expression is up-regulated in 3T3-L1 cells induced to differentiate into adipocytes and that DLK knockdown impairs the expression of PPARγ (peroxisome-proliferator-activated receptor γ), a master regulator of adipogenesis. Because the PPARγ agonist rosiglitazone was found to increase DLK expression in 3T3-L1 cells, we hypothesized that PPARγ is required for the transcriptional activation of the DLK gene. To test this hypothesis, we first examined the effects of pharmacological inhibition or shRNA (small-hairpin RNA)-mediated depletion of PPARγ on DLK accumulation in 3T3-L1 cells undergoing differentiation. In addition to blocking adipocyte conversion of 3T3-L1 cells, inhibition of PPARγ suppressed DLK expression at both the mRNA and protein levels. Moreover, supporting a role for PPARγ in DLK regulation, two potential PPARγ-binding sites identified by bioinformatic tools at positions −611 and −767 upstream of the DLK gene transcriptional start site were shown by electrophoretic mobility-shift assay and chromatin immunoprecipitation to bind PPARγ and its essential heterodimer partner retinoid X receptor as differentiation proceeds. Collectively, these results show that DLK is a novel transcriptional target of PPARγ with functional PPARγ-binding sites in its promoter.

scholarly journals Trans-activation of the human SOX3 promoter by MAZ in NT2/D1 cells

2008 ◽  
Vol 60 (3) ◽  
pp. 379-387 ◽  
Author(s):  
Natasa Kovacevic-Grujicic ◽  
Kazunari Yokoyama ◽  
Milena Stevanovic
Keyword(s):  
Gene Expression ◽  
Neuronal Differentiation ◽  
Gene Transcription ◽  
Binding Sites ◽  
Promoter Activity ◽  
Zinc Finger Protein ◽  
Mobility Shift ◽  
Finger Protein ◽  
Sox3 Gene

In this study, we examine the role of three highly conserved putative binding sites for Myc-associated zinc finger protein (MAZ) in regulation of the human SOX3 gene expression. Electrophoretic mobility shift and supershift assays indicate that complexes formed at two out of three MAZ sites of the human SOX3 promoter involve ubiquitously expressed MAZ protein. Furthermore, in cotransfection experiments we demonstrate that MAZ acts as a positive regulator of SOX3 gene transcription in both undifferentiated and RA-differentiated NT2/D1 cells. Although MAZ increased both basal and RA-induced promoter activity, our results suggest that MAZ does not contribute to RA inducibility of the SOX3 promoter during neuronal differentiation of NT2/D1 cells.

PGC-1α coactivates estrogen-related receptor-α to induce the expression of glucokinase

2010 ◽  
Vol 298 (6) ◽  
pp. E1210-E1218 ◽  
Author(s):  
Liu-Luan Zhu ◽  
Yang Liu ◽  
An-Fang Cui ◽  
Di Shao ◽  
Ji-Chao Liang ◽  
...  
Keyword(s):  
Enzyme Regulation ◽  
Regulatory Function ◽  
Acid Oxidation ◽  
Regulatory Sequence ◽  
Peroxisome Proliferator ◽  
Mobility Shift ◽  
Glucokinase Gene ◽  
Peroxisome Proliferator Activated Receptor ◽  
Insulin Dependent ◽  
Novel Target

Peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) is a key regulator of cellular energy metabolism and regulates processes such as adaptive thermogenesis, hepatic gluconeogenesis, fatty acid oxidation, and mitochondrial biogenesis by coactivating numerous nuclear receptors and transcription factors. Here, we demonstrate the presence of the ERRα binding site in the regulatory sequence of the glucokinase gene and that PGC-1α coactivates ERRα to stimulate the transcription of glucokinase. Simultaneous overexpression of PGC-1α and ERRα potently induced the glucokinase gene expression and its enzymatic activity in primary hepatocytes; however, expression of either PGC-1α or ERRα alone had no significant effect. Electrophoretic mobility shift and chromatin immunoprecipitation assays revealed the interaction of ERRα with the glucokinase promoter. Finally, the knockdown of endogenous ERRα with specific siRNA (siERRα) or pharmacological inhibition of ERRα with XCT790 attenuated insulin-induced glucokinase expression. Taken together, this research identifies glucokinase as a novel target of PGC-1α/ERRα and underscores the regulatory function of ERRα in insulin-dependent enzyme regulation.

Sign in / Sign up

Export Citation Format

Share Document