Insulin stimulates the phosphorylation of the 95,000-dalton subunit of its own receptor.
Cultured human lymphocytes and rat hepatoma cells were labeled with [32P]orthophosphate and the insulin receptor subunits identified by immunoprecipitation and sodium dodecyl sulfate-gel electrophoreses. In both cell types the 95,000-dalton (beta) subunit of the insulin receptor was selectively phosphorylated. Phosphorylation was specifically stimulated by insulin in a dose-dependent fashion after 1 and 15 minutes of hormone treatment, whereas human growth hormone was without effect. This phosphorylation may be a very early event in insulin action.
D000818:Animals; D002478:Cells, Cultured; D013006:Growth Hormone / Q000494:pharmacology; D006801:Humans; D007328:Insulin / Q000494:pharmacology*; D008114:Liver Neoplasms, Experimental / Q000378:metabolism; D008214:Lymphocytes; D046911:Macromolecular Substances; D008970:Molecular Weight; D010766:Phosphorylation; D051381:Rats; D011972:Receptor, Insulin / Q000378:metabolism*
D007328:Insulin; D046911:Macromolecular Substances; D013006:Growth Hormone; D011972:Receptor, Insulin