Stimulation-dependent association of ERP5 with integrin β₃. Platelets (1 × 10⁹/mL) were stimulated in the presence of EGTA, apyrase, and indomethacin at varying concentrations of convulxin (ng/mL) or thrombin (U/mL) for 90 seconds (panel A), or at fixed concentrations of agonist (100 ng Cvx, 1.0 U Thr) for increasing durations (panel B). Following sample lysis, proteins were precipitated and separated with specific antibodies and protein A–sepharose. Immunoblotting was used to show interacting proteins. Blots were stripped and reprobed to verify equivalent levels of target antigen in each sample lane.