The transcription factor nuclear factor I mediates repression of the GLUT4 promoter by insulin.
Insulin represses GLUT4 expression in 3T3-L1 adipocytes through an insulin response element located at bases -706 to -676 in the 5'-flanking sequence. Nuclear proteins related to the nuclear factor I (NF1) family of transcription factors bind to this insulin response element. Mutations that disrupt binding of NF1 proteins to the insulin response element impair the insulin response in reporter gene assays. Insulin treatment of 3T3-L1 adipocytes induces a rapid change in the level of phosphorylation of NF1 proteins, providing a potential mechanism for insulin's ability to regulate gene expression through NF1. Another as yet unidentified protein, not related to NF1, also binds to the GLUT4 insulin response element and is able to mediate partial repression of the GLUT4 promoter in reporter gene assays.
Cooke
D W
DW
Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287-2520, USA. dcooke@welchlink.welch.jhu.edu
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MD
D016475:3T3 Cells; D000818:Animals; D001483:Base Sequence; D022762:CCAAT-Enhancer-Binding Proteins; D015342:DNA Probes; D004268:DNA-Binding Proteins / Q000378:metabolism*; D051275:Glucose Transporter Type 4; D007328:Insulin / Q000494:pharmacology*; D051379:Mice; D008969:Molecular Sequence Data; D009004:Monosaccharide Transport Proteins / Q000235:genetics*; D009124:Muscle Proteins; D051839:NFI Transcription Factors; D009687:Nuclear Proteins; D010766:Phosphorylation; D011401:Promoter Regions, Genetic; D012097:Repressor Proteins / Q000378:metabolism*; D014157:Transcription Factors; D051840:Y-Box-Binding Protein 1
D022762:CCAAT-Enhancer-Binding Proteins; D015342:DNA Probes; D004268:DNA-Binding Proteins; D051275:Glucose Transporter Type 4; D007328:Insulin; D009004:Monosaccharide Transport Proteins; D009124:Muscle Proteins; D051839:NFI Transcription Factors; D009687:Nuclear Proteins; D012097:Repressor Proteins; C495693:Slc2a4 protein, mouse; D014157:Transcription Factors; D051840:Y-Box-Binding Protein 1; C070856:YBX1 protein, human