Figure 7. STXBP5 regulates platelet secretion and activation.

(A) STXBP5 expression in platelets from WT and Stxbp5 KO mice, determined by IB. GAPDH served as a loading control. (B) STXBP5 promoted platelet secretion. Platelets were isolated from WT and Stxbp5 KO mice and stimulated with PBS (resting) or the indicated concentrations of thrombin. Median fluorescence intensity (MFI) changes were measured by flow cytometry after P-selectin externalization or integrin GPIIbIIIα activation (measured by CD62 and JonA fluorescence, respectively), and bioluminescence change was measured after ATP release (n = 3 per treatment). All data are mean ± SD. *P < 0.05 vs. WT.