Effects of 17-hydroxywortmannin on serine/threonine-protein kinases in human blood platelets.
Protein kinases are involved in signal transduction in human blood platelets. A number of renaturable protein kinases have increased in vitro activities compared to controls due to covalent modifications when intact platelets are activated by thrombin. The effect of the platelet inhibitor 17-hydroxywortmannin (HWT) on these protein kinases was investigated in intact platelets and in vitro. HWT inhibits the increase in activity of these protein kinases but it does not interact directly with their catalytic subunits. We conclude that HWT blocks a step in signal transduction which is necessary to activate these protein kinases via covalent modifications.
Kocher
M
M
Theodor Kocher Institute, University of Berne, Switzerland.
Clemetson
K J
KJ
D000730:Androstadienes / Q000494:pharmacology*; D001792:Blood Platelets / Q000187:drug effects / Q000201:enzymology*; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D004789:Enzyme Activation; D006801:Humans; D007700:Kinetics; D015539:Platelet Activation / Q000187:drug effects*; D011489:Protein Denaturation; D011494:Protein Kinases / Q000097:blood*; D012694:Serine; D013912:Threonine
D000730:Androstadienes; C053480:17-hydroxywortmannin; D013912:Threonine; D012694:Serine; D011494:Protein Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases