Stimulation by GTP-binding proteins (Gi, Go) of partially purified phospholipase C activity from human platelet membranes.
A phospholipase C exhibiting preferential hydrolytic activity for polyphosphoinositides was partially purified from the deoxycholate extract of human platelet membranes by Q-Sepharose and Heparin-Sepharose column chromatographies. The activity of this purified phospholipase C free of the GTP gamma S-binding activity was stimulated at a similar level by addition of purified rat brain Gi or Go. These results suggest that GTP-binding proteins may interact directly with a solubilized membrane phospholipase C to stimulate its activity.
D000818:Animals; D001792:Blood Platelets / Q000201:enzymology*; D001921:Brain / Q000201:enzymology; D002118:Calcium / Q000378:metabolism; D004789:Enzyme Activation; D019204:GTP-Binding Proteins / Q000378:metabolism*; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D006160:Guanosine Triphosphate / Q000031:analogs & derivatives / Q000378:metabolism; D006801:Humans; D051381:Rats; D013873:Thionucleotides / Q000378:metabolism; D010738:Type C Phospholipases / Q000097:blood*
D013873:Thionucleotides; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D006160:Guanosine Triphosphate; D010738:Type C Phospholipases; D019204:GTP-Binding Proteins; D002118:Calcium