Effects of insulin and phorbol esters on subcellular distribution of protein kinase C isoforms in rat adipocytes.
Effects of insulin and phorbol esters on subcellular distribution of protein kinase C (PKC) isoforms were examined in rat adipocytes. Both agonists provoked rapid decreases in cytosolic, and/or increases in membrane, immunoreactive PKC-alpha, PKC-beta, PKC-gamma, and PKC-epsilon. Effects of phorbol esters on PKC-alpha redistribution to the plasma membrane, however, were much greater than those of insulin. In contrast, insulin, but not phorbol esters, stimulated the translocation of PKC-beta to the plasma membrane, and provoked changes in PKC-zeta redistribution. Neither agonist altered subcellular distribution of PKC-delta, which was detected only in membrane fractions. Our findings indicate that insulin and phorbol esters have overlapping and distinctly different effects on the subcellular redistribution of specific PKC isoforms.
Farese
R V
RV
J. A. Haley Veterans' Hospital, Tampa, FL.
Standaert
M L
ML
Francois
A J
AJ
Ways
K
K
Arnold
T P
TP
Hernandez
H
H
Cooper
D R
DR
D000273:Adipose Tissue / Q000187:drug effects / Q000201:enzymology* / Q000648:ultrastructure*; D000818:Animals; D002462:Cell Membrane / Q000201:enzymology; D003600:Cytosol / Q000201:enzymology; D007328:Insulin / Q000494:pharmacology*; D007527:Isoenzymes / Q000378:metabolism*; D007700:Kinetics; D011493:Protein Kinase C / Q000378:metabolism*; D051381:Rats; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
D007328:Insulin; D007527:Isoenzymes; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate