Activation of the PKC-isotypes alpha, beta 1, gamma, delta and epsilon by phorbol esters of different biological activities.
Phorbol esters, tetradecanoylphorbolacetate, sapintoxin-A, 12-deoxyphorbol-phenylacetate, 12-deoxyphorbol-phenylacetate-20-acetate, thymeleatoxin and resiniferatoxin were investigated for their abilities to activate the PKC-isotypes alpha, beta 1, gamma, delta and epsilon. PKC-isotypes were grouped into two classes on the basis of Ca2+ requirements for activation by phorbol esters; alpha, beta 1, and gamma being Ca(2+)-dependent forms and delta and epsilon being Ca(2+)-independent. PKC-isotype selective activation by phorbol esters was observed in that SAPA failed to activate PKC-delta up to a concentration of 1000 ng.ml-1 and DOPPA only activated PKC-beta 1 over the same range of concentrations.
Ryves
W J
WJ
Department of Pharmacognosy, School of Pharmacy, University of London, UK.
Evans
A T
AT
Olivier
A R
AR
Parker
P J
PJ
Evans
F J
FJ
D000818:Animals; D002118:Calcium / Q000494:pharmacology; D002417:Cattle; D004789:Enzyme Activation; D007527:Isoenzymes / Q000378:metabolism; D010703:Phorbol Esters / Q000494:pharmacology*; D011493:Protein Kinase C / Q000378:metabolism*
D007527:Isoenzymes; D010703:Phorbol Esters; D011493:Protein Kinase C; D002118:Calcium