title: Repression of the steroidogenic acute regulatory gene by the multifunctional transcription factor Yin Yang 1.
abstract: The transport of cholesterol to the inner mitochondrial membrane by the steroidogenic acute regulatory (StAR) protein is a critical step in steroidogenesis. The current study was designed to examine whether the multifunctional transcription factor Yin Yang 1 (YY1) was able to repress activation of the StAR gene. YY1 bound to three putative YY1-binding sites in the rat StAR promoter. Cotransfection of the StAR promoter linked to a luciferase reporter gene and YY1 in the presence or absence of sterol regulatory element binding protein-1a (SREBP-1a) resulted in transcriptional repression. YY1 was found to colocalize in the nucleus with SREPB-1a. YY1 inhibited SREBP-1a/nuclear factor Y (NF-Y) enhancement of StAR activation and YY1 decreased SREBP-1a binding to a sterol regulatory element in the presence or absence of NF-Y. YY1 also decreased NF-Y binding to a nonconsensus NF-Y-binding motif in the StAR promoter. These studies provide novel information on the mechanisms of YY1-mediated repression of the StAR gene.
authors.affiliation: Department of Obstetrics and Gynecology, University of South Florida, Tampa, Florida 33606, USA.
authors.forename: Anna C
authors.initials: AC
authors.lastname: Nackley
authors.forename: Wendy
authors.initials: W
authors.lastname: Shea-Eaton
authors.forename: Dayami
authors.initials: D
authors.lastname: Lopez
authors.forename: Mark P
authors.initials: MP
authors.lastname: McLean
mesh_terms: D000818:Animals; D015153:Blotting, Western; D022762:CCAAT-Enhancer-Binding Proteins / Q000502:physiology; D019556:COS Cells; D004268:DNA-Binding Proteins / Q000502:physiology; D015536:Down-Regulation / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel; D050981:Erythroid-Specific DNA-Binding Factors; D016297:Mutagenesis, Site-Directed / Q000235:genetics; D010750:Phosphoproteins / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D051780:Sterol Regulatory Element Binding Protein 1; D014157:Transcription Factors / Q000235:genetics*; D014162:Transfection; D050986:YY1 Transcription Factor; D000098682:Steroidogenic Acute Regulatory Protein
chemical_list: D022762:CCAAT-Enhancer-Binding Proteins; D004268:DNA-Binding Proteins; D050981:Erythroid-Specific DNA-Binding Factors; D010750:Phosphoproteins; C497389:Srebf1 protein, rat; D051780:Sterol Regulatory Element Binding Protein 1; D014157:Transcription Factors; D050986:YY1 Transcription Factor; C494700:Yy1 protein, rat; D000098682:Steroidogenic Acute Regulatory Protein