Activation of phosphatidylinositol-3-kinase by insulin is mediated by both A and B human insulin receptor types

Biochem Biophys Res Commun. 1991 Jan 15;174(1):123-7. doi: 10.1016/0006-291x(91)90494-r.

Abstract

Activation of a phosphatidylinositol-3-kinase (PI-3-kinase) is one of the earliest consequences of insulin binding to the receptor. The human insulin receptor exists in two isoforms which differ in the length of the alpha-subunit (HIR-A = 719 aa, HIR-B = 731 aa). To test whether both isoforms transduce an insulin signal on PI-3-kinase we used rat-1-fibroblasts expressing HIR-A or HIR-B. We found that insulin stimulates 32P incorporation into PIP through both HIR-A and HIR-B to a similar extent (approx. 8-10 fold).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cells, Cultured
  • Enzyme Activation / drug effects
  • Humans
  • Insulin / pharmacology*
  • Isoenzymes / metabolism
  • Phosphatidylinositol 3-Kinases
  • Phosphotransferases / biosynthesis*
  • Rats
  • Receptor, Insulin / drug effects
  • Receptor, Insulin / metabolism*

Substances

  • Insulin
  • Isoenzymes
  • Phosphotransferases
  • Phosphatidylinositol 3-Kinases
  • Receptor, Insulin