Insulin but not phorbol ester treatment increases phosphorylation of vinculin by protein kinase C in BC3H-1 myocytes.
Insulin was found to increase protein kinase C activity in BC3H-1 myocytes as determined by in vitro phosphorylation of both a lysine-rich histone fraction (histone III-S) and vinculin. TPA treatment for 20 min or 18 h provoked an apparent loss of histone-directed but not vinculin-directed phosphorylation by cytosolic C-kinase. Thus, chronic TPA-induced 'desensitization' or 'depletion' of cellular protein kinase C is more apparent than real, and is not a valid means for evaluating the role of C-kinase in hormone action.
D000818:Animals; D002478:Cells, Cultured; D006657:Histones / Q000378:metabolism; D007328:Insulin / Q000494:pharmacology*; D009124:Muscle Proteins / Q000378:metabolism*; D009132:Muscles / Q000187:drug effects / Q000378:metabolism; D010766:Phosphorylation; D011493:Protein Kinase C / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D016596:Vinculin
D006657:Histones; D007328:Insulin; D009124:Muscle Proteins; D016596:Vinculin; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate