title: Control of insulin gene expression in pancreatic beta-cells and in an insulin-producing cell line, RIN-5F cells. I. Effects of glucose and cyclic AMP on the transcription of insulin mRNA.
abstract: To define the mechanism whereby glucose regulates islet insulin mRNA content, insulin gene transcription rates were determined in islets labeled with [3H]uridine at low (3.3) or high (17 mM) glucose. Glucose stimulated the transcription of total RNA almost 2-fold and insulin mRNA 5.6-fold. Addition of dibutyryl cAMP to islets in vitro could partially mimic the effect of glucose on insulin gene-specific transcription. In the insulin-producing RIN-5F cell line, glucose did not affect transcription, while cholera toxin acted as a secretagogue and increased total RNA and insulin gene-specific transcription as well. We conclude that glucose exerts a specific stimulatory effect on the transcription of the insulin gene(s) in normal islets and that this effect may be mediated in part by cAMP.
mesh_terms: D000818:Animals; D001483:Base Sequence; D003994:Bucladesine / Q000494:pharmacology; D000242:Cyclic AMP / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects*; D005947:Glucose / Q000494:pharmacology*; D007328:Insulin / Q000235:genetics*; D007515:Islets of Langerhans / Q000378:metabolism*; D010766:Phosphorylation; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D014158:Transcription, Genetic / Q000187:drug effects*
chemical_list: D007328:Insulin; D012333:RNA, Messenger; D003994:Bucladesine; D000242:Cyclic AMP; D005947:Glucose