Insulin-Stimulated Tyrosine Phosphorylation of Protein Kinase Cα: Evidence for Direct Interaction of the Insulin Receptor and Protein Kinase C in Cells

Feng Liu, Richard A. Roth

Research output: Contribution to journalArticle

30 Scopus citations

Abstract

Insulin, in the presence of phorbol esters, was observed to stimulate the tyrosine phosphorylation of a major 80 kDa protein by immunoblotting with anti-phosphotyrosine antibodies in Chinese hamster ovary cells overexpressing the insulin receptor and protein kinase Cα. The protein was specifically immunoprecipitated by antibodies to protein kinase C and anti-phosphotyrosine antibodies were capable of immunoprecipitating protein kinase C enzymatic activity from these cells. When this tyrosine phosphorylated protein kinase C was treated with a tyrosine-specific phosphatase, a 35% decrease in its enzymatic activity was observed and this inhibition was blocked by inclusion of a tyrosine phosphatase inhibitor, vanadate, in the reaction mixture. These results indicate that under certain conditions insulin can stimulate the tyrosine phosphorylation of protein kinase C and this phosphorylation can affect its enzymatic activity.

Original languageEnglish (US)
Pages (from-to)1570-1577
Number of pages8
JournalBiochemical and Biophysical Research Communications
Volume200
Issue number3
DOIs
StatePublished - May 15 1994
Externally publishedYes

ASJC Scopus subject areas

  • Biophysics
  • Biochemistry
  • Molecular Biology
  • Cell Biology

Fingerprint Dive into the research topics of 'Insulin-Stimulated Tyrosine Phosphorylation of Protein Kinase Cα: Evidence for Direct Interaction of the Insulin Receptor and Protein Kinase C in Cells'. Together they form a unique fingerprint.

  • Cite this