Hepatocyte Nuclear Factor 3 (Winged Helix Domain) Activates Trefoil Factor Gene TFF1 through a Binding Motif Adjacent to the TATAA Box

Human dihydrodiol dehydrogenase (DD) 4/aldo-keto reductase (AKR) 1C4 is a major isoform of hepatic DD that oxidizes trans-dihydrodiols of polycyclic aromatic hydrocarbons to reactive and redox-active o-quinones and that reduces several ketone-containing drugs. To investigate the mechanism of transcriptional regulation of the human DD4 gene, the 5′-flanking region of the gene was fused to the luciferase gene. The results of luciferase assays using HepG2 cells and of 1,10-phenanthroline-copper footprinting indicated that two positive regulatory regions were located in regions from -701 to -684 and from -682 to -666. The former region contained a putative hepatocyte nuclear factor (HNF)-4 binding motif, and the latter region contained an HNF-1 consensus binding sequence. DNA fragments of the HNF-4 or HNF-1 motif gave a shifted band in a gel-shift assay with nuclear extracts from HepG2 cells. The formation of the DNA-protein complex was inhibited by the HNF-4 or HNF-1 motif of the α1-antitrypsin gene. A supershift assay using antibodies to human HNF-4α, HNF-4γ and HNF-1α showed that HNF-4α and HNF-4γ bound to the HNF-4 motif, and that HNF-1α interacted with the HNF-1 motif. Introduction of mutations into the HNF-4 or HNF-1 motif lowered the luciferase activity to 10 or 8% respectively of that seen with the intact human DD4 gene. These results indicate that HNF-4α, HNF-4γ and HNF-1α regulate co-operatively the transcription of the human DD4 gene in HepG2 cells.

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Murine chromosomal location of eight members of the hepatocyte nuclear factor 3/fork head winged helix family of transcription factors

Genomics ◽

10.1016/0888-7543(95)80038-n ◽

1995 ◽

Vol 25 (2) ◽

pp. 388-393 ◽

Cited By ~ 17

Author(s):

Karen B. Avraham ◽

Colin Fletcher ◽

David G. Overdier ◽

Derek E. Clevidence ◽

Eseng Lai ◽

...

Keyword(s):

Transcription Factors ◽

Chromosomal Location ◽

Nuclear Factor ◽

Hepatocyte Nuclear Factor ◽

Winged Helix ◽

Fork Head

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Hepatocyte nuclear factor 3/fork head homolog 11 is expressed in proliferating epithelial and mesenchymal cells of embryonic and adult tissues.

Molecular and Cellular Biology ◽

10.1128/mcb.17.3.1626 ◽

1997 ◽

Vol 17 (3) ◽

pp. 1626-1641 ◽

Cited By ~ 252

Author(s):

H Ye ◽

T F Kelly ◽

U Samadani ◽

L Lim ◽

S Rubio ◽

...

Keyword(s):

Oxidative Stress ◽

Transcription Factor ◽

Epithelial Cells ◽

Cell Line ◽

Mrna Levels ◽

Nuclear Factor ◽

Hepatocyte Nuclear Factor ◽

Winged Helix ◽

Fork Head ◽

Ht 29

The hepatocyte nuclear factor 3alpha (HNF-3alpha) and 3beta proteins have homology in the winged helix/fork head DNA binding domain and regulate cell-specific transcription in hepatocytes and in respiratory and intestinal epithelia. In this study, we describe two novel isoforms of the winged helix transcription factor family, HNF-3/fork head homolog 11A (HFH-11A) and HFH-11B, isolated from the human colon carcinoma HT-29 cell line. We show that these isoforms arise via differential splicing and are expressed in a number of epithelial cell lines derived from tumors (HT-29, Caco-2, HepG2, HeLa, A549, and H441). We demonstrate that differentiation of Caco-2 cells toward the enterocyte lineage results in decreased HFH-11 expression and reciprocal increases in HNF-3alpha and HNF-3beta mRNA levels. In situ hybridization of 16 day postcoitus mouse embryos demonstrates that HFH-11 expression is found in the mesenchymal and epithelial cells of the liver, lung, intestine, renal cortex, and urinary tract. Although HFH-11 exhibits a wide cellular expression pattern in the embryo, its adult expression pattern is restricted to epithelial cells of Lieberkühn's crypts of the intestine, the spermatocytes and spermatids of the testis, and the thymus and colon. HFH-11 expression is absent in adult hepatocytes, but its expression is reactivated in proliferating hepatocytes at 4, 24, and 48 h after partial hepatectomy. Consistent with these findings, we demonstrate that HFH-11 mRNA levels are stimulated by intratracheal administration of keratinocyte growth factor in adult lung and its expression in an adult endothelial cell line is reactivated in response to oxidative stress. These experiments show that the HFH-11 transcription factor is expressed in embryonic mesenchymal and epithelial cells and its expression is reactivated in these adult cell types by proliferative signals or oxidative stress.

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Hepatic Expression of the Mouse Angptl8 Gene Is Regulated by Insulin Through Increases in Hepatocyte Nuclear Factor-1

Journal of the Endocrine Society ◽

10.1210/jendso/bvab048.094 ◽

2021 ◽

Vol 5 (Supplement_1) ◽

pp. A47-A48

Author(s):

Takuya Watanabe ◽

Atsushi Ozawa ◽

Yuri Kondo ◽

Kazuhiko Horiguchi ◽

...

Keyword(s):

Promoter Region ◽

Promoter Activity ◽

Time Course ◽

Binding Motif ◽

Light Cycle ◽

Nuclear Factor ◽

Hepatocyte Nuclear Factor ◽

Primary Hepatocytes ◽

Expression Levels ◽

Hepatic Expression

Abstract Angiopoietin-like proteins (ANGPTLs) are a family of proteins structurally similar to angiopoietins. ANGPTL8 is an important regulator of circulating triglyceride (TG) levels in mammals. Increasing evidence revealed an association between ANGPTL8 expression and serum lipid profiles, especially in subjects with metabolic syndrome. Several mice studies demonstrated that Angptl8 is suppressed by fasting and induced by long term refeeding, however the detailed mechanism is still unclear. In humans, ANGPTL8 is mainly expressed in the liver. Therefore, this study aims to investigate the mechanisms that control the refeeding induced increase in the hepatic Angptl8 gene expression. Methods and Results: Twenty-week-old male C57/BL6 mice were used in this study. Mice were fasted for 12h during the dark cycle and re-fed for 30, 60, 120, 240 and 360 minutes during the light cycle. Mice were euthanized after each refeeding time course and tissues were collected. We found even short refeeding times (~60 min) enhanced the expression levels of hepatic Angptl8 in mice. We cloned the mouse Angptl8 gene promoter region. Promoter deletion analyses showed that the basal promoter activity was significantly attenuated by a deletion of -309/-60 region in hepatocytes. A computational motif search revealed the presence of a potential binding motif for hepatocyte nuclear factor 1α/1β (HNF-1α/β) at -84/-68 bp of the promoter. Mutations of the HNF-1 binging site significantly decreased the promoter activity in mouse hepatoma cells (Hepa1-6) and mouse primary hepatocytes, and the promoter carrying the mutated HNF-1 site was not transactivated by co-transfected HNF-1 in a non-hepatic cell line. These findings indicated that HNF-1 was essential and critical factor for the basal expression of Angptl8 in murine liver. In fact, knockdown of Hnf-1 using siRNA method in mouse Hepa1-6 and mouse primary hepatocytes reduced Angptl8 protein levels. We also performed Electrophoretic mobility-shift assays and confirmed the direct binding of Hnf-1 to its Angptl8 promoter binding motif. To elucidate whether refeeding could enhance HNF-1, we checked the expression levels of Hnf-1 in mouse liver. Hnf-1 expression levels of both mRNA and protein were increased after short-term refeeding, paralleling the enhanced expression of the Angptl8. Moreover, insulin-stimulated primary hepatocytes showed increased expression of Angptl8 protein, but knockdown of Hnf-1 completely abolished this enhancement by insulin. Chromatin immunoprecipitation (ChIP) analyses confirmed the recruitment of endogenous Hnf-1 to the Angptl8 promoter region and it was strongly induced by insulin. Conclusion: HNF-1 plays essential role in hepatocyte-specific and refeeding-induced rapid increases in Angptl8 expression via insulin.

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