Phosphorylation of platelet actin-binding protein during platelet activation

摘要: In this study we have followed the 32P-labeling of actin-binding protein as a function platelet activation. Utilizing polyacrylamide-sodium dodecyl sulfate gel electrophoresis to resolve total samples, found 2--3-fold labeling increases in 30--60 sec after thrombin stimulation. Somewhat larger were observed for 40,000 and 20,000 apparent molecular weight peptides. The was identified on gels by coelectrophoresis with purified protein, its presence cytoskeletal cores prepared detergent extraction activated 32P-labeled platelets, direct immunoprecipitation antibodies against guinea pig vas deferens filamin (actin-binding protein). addition, these indicated that closely associated platelet's cytoskeleton. Following over an 8-min time course revealed aggregating samples rapid dephosphorylation almost initial levels occurred between 3 5 min. A similar curve obtained peptide. However, not if aggregation prevented chelating external calcium or using thrombasthenic platelets lacking response. Thus, cell-cell contact would seem be crucial initiating