title: Transcription factor cycling on the insulin promoter.
abstract: Using MIN6 beta-cells and chromatin immunoprecipitation (ChIP) assays, the chronological sequence of binding of MafA, E47/beta2 and PDX-1 to the insulin promoter in living beta-cells were investigated. All four factors were shown to bind to the mouse insulin 2 promoter in a cyclical manner with a periodicity of approximately 10-15 min. The cyclical binding of MafA, E47 and beta2 was largely unaffected by the glucose or insulin concentration in the media. However, the binding and cycling of PDX-1 was markedly abolished in low glucose (1 mM), and this was reversed in the presence of low concentrations of insulin.
authors.affiliation: School of Medical Sciences, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK.
authors.forename: John
authors.initials: J
authors.lastname: Barrow
authors.forename: Colin W
authors.initials: CW
authors.lastname: Hay
authors.forename: Laura A
authors.initials: LA
authors.lastname: Ferguson
authors.forename: Hilary M
authors.initials: HM
authors.lastname: Docherty
authors.forename: Kevin
authors.initials: K
authors.lastname: Docherty
mesh_terms: D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D005947:Glucose / Q000378:metabolism; D018398:Homeodomain Proteins / Q000378:metabolism*; D006801:Humans; D007328:Insulin / Q000235:genetics* / Q000378:metabolism; D050417:Insulin-Secreting Cells / Q000166:cytology / Q000378:metabolism; D051473:Maf Transcription Factors, Large / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D016415:Sequence Alignment; D051820:TCF Transcription Factors / Q000378:metabolism*; D015534:Trans-Activators / Q000378:metabolism*; D058125:Transcription Factor 7-Like 1 Protein
chemical_list: D018398:Homeodomain Proteins; D007328:Insulin; D051473:Maf Transcription Factors, Large; C485160:Mafa protein, mouse; D051820:TCF Transcription Factors; C544912:TCF7L1 protein, human; C544913:Tcf7l1 protein, mouse; D015534:Trans-Activators; D058125:Transcription Factor 7-Like 1 Protein; C084010:pancreatic and duodenal homeobox 1 protein; D005947:Glucose