Fig. 3.
Association of WASP with the Triton X-100–insoluble residue. Platelets were lysed with Triton X-100-EGTA buffer before or after stimulation with thrombin (1 U/mL), with or without stirring. Lysates were separated by high speed centrifugation into soluble and insoluble residues. Proteins from each fraction were separated by 10% SDS-PAGE and immunoblotted with anti-WASP antiserum 503. Lane 1, Triton X-100–soluble residue of resting cells (7.5 × 106cells). Lane 2, Triton X-100–insoluble residue of resting cells (3.0 × 107 cells). Lanes 3 through 5, Triton X-100–insoluble residue from 3.0 × 107 cells, prepared 15 seconds, 1 minute, and 5 minutes after exposure to thrombin (1 U/mL) with stirring, respectively. Lane 6, Triton X-100–insoluble residue of cells (3.0 × 107 cells) stimulated for 5 minutes with thrombin but without stirring.