title: Regulation of human coagulation factor X gene expression by GATA-4 and the Sp family of transcription factors.
abstract: Serine protease factor Xa plays a critical role in the coagulation cascade. Zymogen factor X is synthesized and modified in the liver. To understand the mechanisms governing the liver-specific expression of factor X, the proximal promoter of human factor X was previously characterized. Two crucial cis elements at -73 and -128 and their cognate binding proteins, HNF-4 and NF-Y, respectively, were identified. In this report, studies are extended to 3 additional cis elements within the factor X promoter. Using gel mobility shift assays, the liver-enriched protein GATA-4 was identified as the protein binding to the GATA element at -96. GATA-4 transactivates the factor X promoter 28-fold in transient transfection experiments. It was also determined that the Sp family of transcription factors binds 2 DNase I-footprinted sites at -165 and -195. Disruption of Sp protein binding at either site reduces the promoter activity by half. Simultaneous disruption of both sites reduces the promoter activity 8-fold. This is the first report indicating the involvement of GATA-4 in the regulation of clotting factor expression. These observations provide novel insight into mechanisms by which the vitamin K-dependent coagulation factors are regulated.
authors.affiliation: Department of Pediatrics, University of Pennsylvania, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
authors.forename: H L
authors.initials: HL
authors.lastname: Hung
authors.forename: E S
authors.initials: ES
authors.lastname: Pollak
authors.forename: R D
authors.initials: RD
authors.lastname: Kudaravalli
authors.forename: V
authors.initials: V
authors.lastname: Arruda
authors.forename: K
authors.initials: K
authors.lastname: Chu
authors.forename: K A
authors.initials: KA
authors.lastname: High
mesh_terms: D016475:3T3 Cells; D000818:Animals; D001665:Binding Sites; D018983:DNA Footprinting; D004268:DNA-Binding Proteins / Q000502:physiology*; D004331:Drosophila melanogaster / Q000166:cytology; D005170:Factor X / Q000096:biosynthesis / Q000235:genetics*; D050991:GATA4 Transcription Factor; D005786:Gene Expression Regulation; D017930:Genes, Reporter; D005813:Genes, Synthetic; D006579:Heterozygote; D006801:Humans; D008099:Liver / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D016297:Mutagenesis, Site-Directed; D009928:Organ Specificity; D010314:Partial Thromboplastin Time; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000235:genetics; D016329:Sp1 Transcription Factor / Q000502:physiology*; D051705:Sp3 Transcription Factor; D014157:Transcription Factors / Q000502:physiology*; D015533:Transcriptional Activation; D014162:Transfection
chemical_list: D004268:DNA-Binding Proteins; D050991:GATA4 Transcription Factor; D011993:Recombinant Fusion Proteins; D016329:Sp1 Transcription Factor; D014157:Transcription Factors; D051705:Sp3 Transcription Factor; D005170:Factor X