Effects of insulin on the translocation of protein kinase C-theta and other protein kinase C isoforms in rat skeletal muscles.
Protein kinase C (PKC)-theta is a newly recognized major PKC isoform in skeletal muscle. In this study we found that insulin provoked rapid biphasic increases in membrane-associated immunoreactive PKC-theta, as well as PKC-alpha, PKC-beta and PKC-epsilon, in rat soleus muscles incubated in vitro. Effects of insulin on PKC isoforms in the soleus were comparable in magnitude with those of phorbol esters. Increases in membrane-associated PKC-theta, PKC-alpha, PKC-beta and PKC-epsilon were also observed in rat gastrocnemius muscles after insulin treatment in vivo. Our findings suggest that PKC-theta, like other diacylglycerol-sensitive PKC isoforms (alpha, beta and epsilon), may play a role in insulin action in skeletal muscles.
Yamada
K
K
Department of Internal Medicine, J.A. Haley Veterans' Hospital, University of South Florida, Tampa 33612, USA.
Avignon
A
A
Standaert
M L
ML
Cooper
D R
DR
Spencer
B
B
Farese
R V
RV
D000818:Animals; D002451:Cell Compartmentation / Q000187:drug effects; D002462:Cell Membrane / Q000201:enzymology; D003600:Cytosol / Q000201:enzymology; D006003:Glycogen / Q000378:metabolism; D007328:Insulin / Q000494:pharmacology*; D007527:Isoenzymes / Q000378:metabolism; D050356:Lipid Metabolism; D008297:Male; D009132:Muscles / Q000201:enzymology*; D011493:Protein Kinase C / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D007328:Insulin; D007527:Isoenzymes; D006003:Glycogen; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate