The protein kinase inhibitor staurosporine, like phorbol esters, induces the association of protein kinase C with membranes.
Staurosporine induced the association of purified protein kinase C (PKC) with inside-out vesicles from erythrocyte membranes. This effect was Ca2+ and concentration dependent, and maximum PKC translocation was observed at 50 nM staurosporine and 0.5 microM Ca2+, or higher. A significant effect of staurosporine was already obtained at free Ca2+ concentrations in the range found in resting cells. Under these conditions, the PKC activator 4-phorbol 12,13-dibutyrate was by itself inactive, but enhanced translocation by staurosporine. Protein phosphorylation by staurosporine-translocated PKC was inhibited in the presence or absence of phorbol esters. Translocation and inhibition of PKC occurred in the same staurosporine concentration range.
Wolf
M
M
Theodor-Kocher-Institut, University of Bern, Switzerland.
Baggiolini
M
M
D000470:Alkaloids / Q000494:pharmacology*; D001792:Blood Platelets / Q000201:enzymology; D004910:Erythrocyte Membrane / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D010766:Phosphorylation; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000097:blood*; D019311:Staurosporine
D000470:Alkaloids; D011493:Protein Kinase C; D019311:Staurosporine