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Yerra VG, Drosatos K. Specificity Proteins (SP) and Krüppel-like Factors (KLF) in Liver Physiology and Pathology. Int J Mol Sci 2023; 24:4682. [PMID: 36902112 PMCID: PMC10003758 DOI: 10.3390/ijms24054682] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 02/21/2023] [Accepted: 02/23/2023] [Indexed: 03/04/2023] Open
Abstract
The liver acts as a central hub that controls several essential physiological processes ranging from metabolism to detoxification of xenobiotics. At the cellular level, these pleiotropic functions are facilitated through transcriptional regulation in hepatocytes. Defects in hepatocyte function and its transcriptional regulatory mechanisms have a detrimental influence on liver function leading to the development of hepatic diseases. In recent years, increased intake of alcohol and western diet also resulted in a significantly increasing number of people predisposed to the incidence of hepatic diseases. Liver diseases constitute one of the serious contributors to global deaths, constituting the cause of approximately two million deaths worldwide. Understanding hepatocyte transcriptional mechanisms and gene regulation is essential to delineate pathophysiology during disease progression. The current review summarizes the contribution of a family of zinc finger family transcription factors, named specificity protein (SP) and Krüppel-like factors (KLF), in physiological hepatocyte functions, as well as how they are involved in the onset and development of hepatic diseases.
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Affiliation(s)
| | - Konstantinos Drosatos
- Metabolic Biology Laboratory, Cardiovascular Center, Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
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2
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Chang TT, Hughes-Fulford M. Molecular mechanisms underlying the enhanced functions of three-dimensional hepatocyte aggregates. Biomaterials 2013; 35:2162-71. [PMID: 24332390 DOI: 10.1016/j.biomaterials.2013.11.063] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Accepted: 11/21/2013] [Indexed: 12/17/2022]
Abstract
Three-dimensional (3D) culture of hepatocytes leads to improved and prolonged synthetic and metabolic functions, but the underlying molecular mechanisms are unknown. In order to investigate the role of 3D cell-cell interactions in maintaining hepatocyte differentiated functions ex vivo, primary mouse hepatocytes were cultured either as monolayers on tissue culture dishes (TCD) or as 3D aggregates in rotating wall vessel (RWV) bioreactors. Global gene expression analyses revealed that genes upregulated in 3D culture were distinct from those upregulated during liver development and liver regeneration. Instead, they represented a diverse array of hepatocyte-specific functional genes with significant over-representation of hepatocyte nuclear factor 4α (Hnf4a) binding sites in their promoters. Expression of Hnf4a and many of its downstream target genes were significantly increased in RWV cultures as compared to TCD. Conversely, there was concomitant suppression of mesenchymal and cytoskeletal genes in RWV cultures that were induced in TCDs. These findings illustrate the importance of 3D cell-cell interactions in maintaining fundamental molecular pathways of hepatocyte function and serve as a basis for rational design of biomaterials that aim to optimize hepatocyte functions ex vivo for biomedical applications.
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Affiliation(s)
- Tammy T Chang
- Department of Surgery, University of California, San Francisco, CA 94143, USA; Liver Center, University of California, San Francisco, CA 94143, USA.
| | - Millie Hughes-Fulford
- Department of Medicine, University of California, San Francisco, CA 94143, USA; Northern California Institute for Research and Education, San Francisco, CA 94121, USA
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3
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CK2 kinase activity but not its binding to CK2 promoter regions is implicated in the regulation of CK2α and CK2β gene expressions. Mol Cell Biochem 2013; 384:71-82. [DOI: 10.1007/s11010-013-1782-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Accepted: 08/09/2013] [Indexed: 12/11/2022]
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4
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Cleuren ACA, Van der Linden IK, De Visser YP, Wagenaar GTM, Reitsma PH, Van Vlijmen BJM. 17α-Ethinylestradiol rapidly alters transcript levels of murine coagulation genes via estrogen receptor α. J Thromb Haemost 2010; 8:1838-46. [PMID: 20524981 DOI: 10.1111/j.1538-7836.2010.03930.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Oral estrogen use is associated with changes in plasma levels of many coagulation proteins. OBJECTIVE To gain more insight into the underlying mechanism of estrogen-induced changes in coagulation. METHODS Ovariectomized female mice were used to study the impact of oral 17α-ethinylestradiol (EE) on plasma coagulation, hepatic coagulation gene transcript levels, and dependence on estrogen receptor (ER) α and ERβ. RESULTS Ten days of oral EE treatment resulted in significantly reduced plasma activity levels of factor (F)VIII, FXII, combined FII/FVII/FX and antithrombin, whereas FIX activity significantly increased. Regarding hepatic transcript levels, oral EE caused significant decreases in fibrinogen-γ, FII, FV, FVII, FX, FXII, antithrombin, protein C, protein Z, protein Z inhibitor and heparin cofactor II mRNA levels, whereas FXI levels significantly increased and transcript levels of FVIII, FIX, protein S and α(2) -antiplasmin remained unaffected. All EE-induced coagulation-related changes were neutralized by coadministration of the non-specific ER antagonist ICI182780. In addition, ERα-deficient mice lacked the EE-induced changes in plasma coagulation and hepatic transcript profile, whereas ERβ-deficient mice responded similarly to non-deficient littermate controls. A crucial role for the ER was further demonstrated by its rapid effects on transcription, within 2.5-5 h after EE administration, suggesting a short chain of events leading to its final effects. CONCLUSIONS Oral EE administration has a broad impact on the mouse coagulation profile at the level of both plasma and hepatic mRNA levels. The effects on transcription are rapidly induced, mostly downregulatory, and principally mediated by ERα.
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Affiliation(s)
- A C A Cleuren
- Einthoven Laboratory for Experimental Vascular Medicine, Department of Thrombosis and Haemostasis, Leiden University Medical Center, Leiden, the Netherlands.
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5
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Evidence for an overlapping role of CLOCK and NPAS2 transcription factors in liver circadian oscillators. Mol Cell Biol 2008; 28:3070-5. [PMID: 18316400 DOI: 10.1128/mcb.01931-07] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The mechanisms underlying the circadian control of gene expression in peripheral tissues and influencing many biological pathways are poorly defined. Factor VII (FVII), the protease triggering blood coagulation, represents a valuable model to address this issue in liver since its plasma levels oscillate in a circadian manner and its promoter contains E-boxes, which are putative DNA-binding sites for CLOCK-BMAL1 and NPAS2-BMAL1 heterodimers and hallmarks of circadian regulation. The peaks of FVII mRNA levels in livers of wild-type mice preceded those in plasma, indicating a transcriptional regulation, and were abolished in Clock(-/-); Npas2(-/-) mice, thus demonstrating a role for CLOCK and NPAS2 circadian transcription factors. The investigation of Npas2(-/-) and Clock(Delta19/Delta19) mice, which express functionally defective heterodimers, revealed robust rhythms of FVII expression in both animal models, suggesting a redundant role for NPAS2 and CLOCK. The molecular bases of these observations were established through reporter gene assays. FVII transactivation activities of the NPAS2-BMAL1 and CLOCK-BMAL1 heterodimers were (i) comparable (a fourfold increase), (ii) dampened by the negative circadian regulators PER2 and CRY1, and (iii) abolished upon E-box mutagenesis. Our data provide the first evidence in peripheral oscillators for an overlapping role of CLOCK and NPAS2 in the regulation of circadianly controlled genes.
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Jackson AA, Cronin KR, Zachariah R, Carew JA. CCAAT/enhancer-binding protein-beta participates in insulin-responsive expression of the factor VII gene. J Biol Chem 2007; 282:31156-65. [PMID: 17675296 DOI: 10.1074/jbc.m704694200] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Expression of the human coagulation factor VII (FVII) gene by hepatoma cells was modulated in concert with levels of glucose and insulin in the culture medium. In low glucose medium without insulin, amounts of both FVII mRNA and secreted FVII protein were coordinately increased; in the presence of glucose with insulin, both were decreased. Analysis of the FVII promoter showed that these effects could be reproduced in a reporter-gene system, and a small promoter element immediately upstream of the translation start site of the gene, which mediated these effects, was identified. Mutation of this element largely abrogated the glucose/insulin-responsive change in expression of the reporter gene. Several members of the CCAAT/enhancer-binding protein family were found to be capable of binding the identified sequence element but not the mutated element. The expression of a FVII minigene directed by a segment of the native FVII promoter responded to co-expressed activating and inhibiting forms of CCAAT/enhancer-binding protein beta.
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Affiliation(s)
- Audrey A Jackson
- Veterans Affairs Boston Healthcare System, West Roxbury, Massachusetts 02132, USA
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Inoue Y, Peters LL, Yim SH, Inoue J, Gonzalez FJ. Role of hepatocyte nuclear factor 4alpha in control of blood coagulation factor gene expression. J Mol Med (Berl) 2005; 84:334-44. [PMID: 16389552 DOI: 10.1007/s00109-005-0013-5] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2005] [Accepted: 08/25/2005] [Indexed: 11/28/2022]
Abstract
Hepatocyte nuclear factor 4alpha (HNF4alpha) plays an important role in the maintenance of many liver-specific functions. Liver-specific HNF4alpha-null mice were used to determine whether hepatic HNF4alpha regulates blood coagulation in vivo. These mice exhibited reduced expression of hepatic coagulation factors V, IX, XI, XII, and XIIIB and a prolonged activated partial thromboplastin time but not prothrombin time. Promoter analysis of the mouse FXII and FXIIIB genes was performed to determine whether HNF4alpha directly regulates the genes encoding these coagulation factors. Sequence analysis revealed the presence of one and two HNF4alpha binding sites in the mouse FXII and FXIIIB genes, respectively. Using transient transfection and electrophoretic mobility shift analyses with the mouse FXII and FXIIIB promoters, it was established that the high levels of promoter activity were dependent on HNF4alpha binding sites and the expression of HNF4alpha. In conclusion, HNF4alpha has a critical role in blood coagulation homeostasis by directing transcription of the FXII and XIIIB genes.
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Affiliation(s)
- Yusuke Inoue
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
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Lay AJ, Liang Z, Rosen ED, Castellino FJ. Mice with a severe deficiency in protein C display prothrombotic and proinflammatory phenotypes and compromised maternal reproductive capabilities. J Clin Invest 2005; 115:1552-61. [PMID: 15902301 PMCID: PMC1089798 DOI: 10.1172/jci24030] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2004] [Accepted: 03/29/2005] [Indexed: 12/11/2022] Open
Abstract
Anticoagulant protein C (PC) is important not only for maintenance of normal hemostasis, but also for regulating the host immune response during inflammation. Because mice with a designed total genetic deficiency in PC (PC-/- mice) die soon after birth, attempts to dissect PC function in various coagulation/inflammation-based pathologies through use of mice with less than 50% of normal PC levels have not been successful to date. In the current investigation, we have used a novel transgenic strategy to generate different mouse models expressing 1-18% of normal PC levels. In contrast to PC-/- mice, mice with only partial PC deficiency survived beyond birth and also developed thrombosis and inflammation. The onset and severity of these phenotypes vary significantly and are strongly dependent on plasma PC levels. Our findings additionally provide the first evidence that maternal PC is vital for sustaining pregnancy beyond 7.5 days postcoitum, likely by regulating the balance of coagulation and inflammation during trophoblast invasion. These low PC-expressing transgenic mouse lines provide novel animal models that can be used to elucidate the importance of PC in maintenance of the organism and in disease.
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Affiliation(s)
- Angelina J Lay
- W.M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, Indiana 46556, USA
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Barbier O, Girard H, Inoue Y, Duez H, Villeneuve L, Kamiya A, Fruchart JC, Guillemette C, Gonzalez FJ, Staels B. Hepatic Expression of the UGT1A9 Gene Is Governed by Hepatocyte Nuclear Factor 4α. Mol Pharmacol 2004; 67:241-9. [PMID: 15470081 DOI: 10.1124/mol.104.003863] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
UDP-glucuronosyltransferase (UGT) enzymes catalyze the glucuronidation reaction, which is a major pathway in the catabolism and elimination of numerous endo- and xenobiotics. Among the UGT enzyme family members, the UGT1A7, UGT1A8, UGT1A9, and UGT1A10 isoforms are issued from a single gene through differential splicing. However, these enzymes display distinct tissue-specific expression patterns. Indeed, UGT1A7, UGT1A8, and UGT1A10 are exclusively expressed in extrahepatic tissues, whereas UGT1A9 transcripts are found at high concentrations in liver. In the present study, we report that the liver-enriched hepatocyte nuclear factor 4 (HNF4)-alpha controls the hepatic expression of the UGT1A9 enzyme. Liver-specific disruption of the HNF4alpha gene in mice drastically decreases liver UGT1A9 mRNA levels. Furthermore, an HNF4alpha response element (HNF4alpha RE) was identified in the promoter of human UGT1A9 at position -372 to -360 base pairs by transient transfection, electrophoretic mobility shift assays, and chromatin immunoprecipitation experiments. It is interesting that this response element is absent in the proximal UGT1A7, UGT1A8, and UGT1A10 gene promoters. In conclusion, the present study identifies HNF4alpha as a major factor for the control of UGT1A9 hepatic expression and suggests that the absence of UGT1A7, UGT1A8, and UGT1A10 expression in the liver is caused by, at least in part, a few base pair changes in their promoter sequences in the region corresponding to the HNF4alpha RE of the UGT1A9 gene.
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Affiliation(s)
- Olivier Barbier
- Unité INSERM 545, Institut Pasteur de Lille, 1 rue du Pr Calmette, BP 245, 59019 Lille, France
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Ivanov GS, Kater JM, Jha SH, Stutius EA, Sabharwal R, Tricarico MD, Ginsburg GS, Ozer JS. Sp and GATA factors are critical for Apolipoprotein AI downstream enhancer activity in human HepG2 cells. Gene 2004; 323:31-42. [PMID: 14659877 DOI: 10.1016/j.gene.2003.08.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The factors that bind to the hepatic-specific human apolipoprotein AI (apoAI) 48-bp downstream enhancer (DSE) were identified and characterized by electrophoretic mobility shift assays. A significant homology was shown between the histone 4 (H4) promoters and the hepatic-specific human apoAI DSE at Sp1 and H4TF2 binding sites. Human HepG2 nuclear extracts were used to form four specific complexes with the DSE (referred to as apoAI DSE-1, -2, -3, and -4). The apoAI DSE-1 and -2 complexes showed similar binding specificity to the Sp/H4TF1 consensus site within the apoAI DSE. The apoAI DSE-1 complex was predominantly recognized by anti-Sp1 and Sp3 sera in gel shift assays, indicating that the DSE was recognized by multiple Sp family members. Nuclear extracts that were prepared from retinoic acid treated HepG2 cells showed increased levels of Sp factors in gel shift and Western blot assays. The apoAI DSE-2 complex was identified as H4TF1 and formed in the absence of magnesium chloride. The apoAI DSE-3 complex bound to a consensus GATA element within the DSE that was recognized by recombinant human GATA-6 as well. The apoAI DSE-3 complex was completely disrupted by a GATA-4 antibody in EMSA. GATA-4 and -6 were detected in nuclear extracts prepared from retinoic acid treated HepG2 cells using Western blot assays. The highest apoAI DSE-3 levels were observed with retinoic acid treated HepG2 cell nuclear extracts in EMSA. ApoAI DSE-4 is a multi-factor complex that includes an Sp/H4TF1 factor and either H4TF2 or apoAI DSE-3. Because apoAI DSE mutations revealed transcription defects in transient transfection assays, we conclude that the entire DSE sequence is required for full apoAI transcriptional activity in HepG2 cells.
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Affiliation(s)
- Gleb S Ivanov
- Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, 715 Albany Street, Building R-618, Boston, MA 02118, USA
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Kryszke MH, Moura-Neto V, Lilienbaum A, Paulin D, Auclair C. Involvement of histone H4 gene transcription factor 1 in downregulation of vimentin gene expression during skeletal muscle differentiation. FEBS Lett 2001; 491:30-4. [PMID: 11226413 DOI: 10.1016/s0014-5793(01)02142-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Upon in vitro myogenesis, the intermediate filament protein vimentin is replaced by desmin, the switch in gene expression occurring essentially at the transcriptional level. Trying to elucidate the molecular mechanisms of this genetic control, we show here that the vimentin promoter is specifically recognized and activated by a protein most probably identical to H4TF-1, and that this factor is present in proliferating myoblasts but disappears upon fusion of these cells into multinucleated myotubes. Our results suggest that H4TF-1 is a differentiation stage-specific factor involved in the downregulation of vimentin gene expression during myogenesis.
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Affiliation(s)
- M H Kryszke
- CNRS UMR 8532, Institut Gustave Roussy, 39 rue Camille Desmoulins, 94800 Villejuif, France.
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Xu Y, Kiningham KK, Devalaraja MN, Yeh CC, Majima H, Kasarskis EJ, St Clair DK. An intronic NF-kappaB element is essential for induction of the human manganese superoxide dismutase gene by tumor necrosis factor-alpha and interleukin-1beta. DNA Cell Biol 1999; 18:709-22. [PMID: 10492402 DOI: 10.1089/104454999314999] [Citation(s) in RCA: 183] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Tumor necrosis factor-alpha (TNF) and interleukin-1beta (IL-1) are cytokines that induce expression of various genes through activation of the redox-sensitive transcription factor nuclear factor-kappaB (NF-kappaB). We have previously cloned the entire human MnSOD (SOD2) gene and found several NF-kappaB-binding sites in the 5' and 3' flanking and intronic regions. To test whether these putative NF-kappaB-binding sites are able to respond to TNF and IL-1, we performed induction analysis using various deletion constructs ligated to a luciferase reporter gene. We found that the 5' and 3' flanking regions containing several NF-kappaB-binding sites do not mediate MnSOD induction by TNF or IL-1. When a 342-bp intron 2 fragment containing NF-kappaB, C/EBP, and NF-1 binding sites was linked to the basal promoter of the SOD2 gene, transcriptional activities were significantly increased in response to TNF and IL-1 in an orientation- and position-independent manner. To accurately identify the element that is most critical for the enhancer activity, deletions and specific mutations of each individual site were studied. The results indicated that the NF-kappaB binding site is essential but not sufficient for TNF- or IL-1-mediated induction. Furthermore, NF-kappaB elements in the 5' and 3' flanking regions could be made to function in TNF or IL-1 induction when they were transposed to the intronic fragment. Taken together, these results suggest that an NF-kappaB element and its location in the SOD2 gene is critical for TNF/IL-1-mediated induction. However, a complex interaction between NF-kappaB and other transcription elements is needed for a high-level induction.
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Affiliation(s)
- Y Xu
- Graduate Center for Toxicology, University of Kentucky, Lexington 40536-0305, USA
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Reinhart AJ, Williams SC, Clark BJ, Stocco DM. SF-1 (steroidogenic factor-1) and C/EBP beta (CCAAT/enhancer binding protein-beta) cooperate to regulate the murine StAR (steroidogenic acute regulatory) promoter. Mol Endocrinol 1999; 13:729-41. [PMID: 10319323 DOI: 10.1210/mend.13.5.0279] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The steroidogenic acute regulatory (StAR) protein mediates the rate-limiting step of steroidogenesis, which is the transfer of cholesterol to the inner mitochondrial membrane. In steroidogenic tissues, StAR expression is acutely regulated by trophic hormones through a cAMP second messenger pathway, leading to increased StAR mRNA levels within 30 min, reaching maximal levels after 4-6 h of stimulation. The molecular mechanisms underlying such regulation remain unknown. We have examined the StAR promoter for putative transcription factor-binding sites that may regulate transcription in a developmental and/or hormone-induced context. Through sequence analysis, deoxyribonuclease I (DNAse I) footprinting and electrophoretic mobility shift assays (EMSAs), we have identified two putative CCAAT/enhancer binding protein (C/EBP) DNA elements at -113 (C1) and -87 (C2) in the mouse StAR promoter. Characterization of these sites by EMSA indicated that C/EBP beta bound with high affinity to C1 and C2 was a low-affinity C/EBP site. Functional analysis of these sites in the murine StAR promoter showed that mutation of one or both of these binding sites decreases both basal and (Bu)2cAMP-stimulated StAR promoter activity in MA-10 Leydig tumor cells, without affecting the fold activation [(Bu)2cAMP-stimulated/basal] of the promoter. Furthermore, we have demonstrated that these two C/EBP binding sites are required for steroidogenic factor-1 (SF-1)-dependent transactivation of the StAR promoter in a nonsteroidogenic cell line. These data indicate that in addition to SF-1, C/EBP beta is involved in the transcriptional regulation of the StAR gene and may play an important role in developmental and hormone-responsive regulation of steroidogenesis.
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Affiliation(s)
- A J Reinhart
- Department of Cell Biology and Biochemistry, Texas Tech University Health Science Center Lubbock 79430, USA
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Abstract
We have identified a point mutation in the promoter of the factor VII gene responsible for a severe bleeding disorder in a patient from a large French-Canadian family with known consanguinity. The proband has an extremely low plasma level of factor VII antigen and factor VII coagulant activity (<1 percent of normal) and suffers from hemarthroses and chronic arthropathy. Sequencing of the patient’s factor VII 5′ flanking region, intron/exon junctions, and coding regions showed a homozygous point mutation, a C to G transversion at position −94 relative to the translation start site. We show here that this mutation prevented binding of transcription factor Sp1 and of other nuclear proteins to this region of the factor VII promoter and resulted in a 20-fold reduction in reporter gene expression in HepG2 cells. These data underscore the importance of this region of the factor VII promoter for in vivo expression of the factor VII gene.© 1998 by The American Society of Hematology.
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Severe Factor VII Deficiency Due to a Mutation Disrupting an Sp1 Binding Site in the Factor VII Promoter. Blood 1998. [DOI: 10.1182/blood.v92.5.1639] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractWe have identified a point mutation in the promoter of the factor VII gene responsible for a severe bleeding disorder in a patient from a large French-Canadian family with known consanguinity. The proband has an extremely low plasma level of factor VII antigen and factor VII coagulant activity (<1 percent of normal) and suffers from hemarthroses and chronic arthropathy. Sequencing of the patient’s factor VII 5′ flanking region, intron/exon junctions, and coding regions showed a homozygous point mutation, a C to G transversion at position −94 relative to the translation start site. We show here that this mutation prevented binding of transcription factor Sp1 and of other nuclear proteins to this region of the factor VII promoter and resulted in a 20-fold reduction in reporter gene expression in HepG2 cells. These data underscore the importance of this region of the factor VII promoter for in vivo expression of the factor VII gene.© 1998 by The American Society of Hematology.
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