Distribution of rac and cdc42 in platelets after activation with 25 μm TRAP.

Distribution of rac and cdc42 in platelets at rest and after activation with 25 μmol/L TRAP. Platelets were permeabilized with buffer containing Triton X-100. (A) Quantitation of the amount of rac or cdc42 that co-sediments with the actin-based cytoskeleton relative to the total. (top inset) Representative immunoblot showing the incorporation of cdc42 into the detergent insoluble cytoskeleton (100 000gpellet). (bottom inset) Immunoblot for rac in the high-speed supernatant (S) or pellet (P) from detergent lysates. (B) Distribution of rac and cdc42 in cytoskeletal pellet (P) or supernatant (S) from platelets permeabilized with buffers containing 0.1% Triton X-100 (TX-100) or 0.5% octyl-glucoside (OG). The bulk of rac and cdc42 are associated with the OG-insoluble material. (C) Effect of 100 μmol/L GDP, GTP, GDPβS, or GTPγS on the movement of cdc42 into actin cytoskeleton of platelets permeabilized with 0.1% TX-100.