GPIIb-IIIa activation in Tln1^R35E/R35E, Apbb1ip^KO/KO(RIAM-null) platelets. (A) Western blot analysis of talin 1 and RIAM expression in platelets. Vinculin was used as a loading control. (B-C) Normal GPIIb-IIIa integrin activation in Tln1^R35E/R35E, Apbb1ip^−/− platelets. Flow cytometry assay to measure binding of washed platelets to fibrinogen (B) or GPIX-labeled platelets in whole blood to Jon/A antibody (C). Bar graphs represent MFI ± SEM (n = 4 mice, representative of 2 independent experiments).