CD36 is required for TSR-induced SHP-1 association with VEGFR2 and VEGFR2 dephosphorylation in MVEC. (A) MVEC were transfected with CD36 or control siRNA for 6 hours and then cultured for 48 hours before analysis of CD36 expression by immunoprecipitation and western blot. (B) MVEC transfected as in (A) were treated with 10 nmol/L TSR in low-serum medium for 4 hours and then exposed to 50 ng/mL VEGF for 5 minutes. VEGFR2 phosphorylation was analyzed by western blot with an antibody to pTyr1175. Blots were reprobed with an antibody to VEGFR2. The level of phosphorylation was shown as the ratio of phosphorylated to total VEGFR2 (B). (C) MVEC transfected as in (B) were treated with 10 nmol/L TSR in low-serum medium for 4 hours and then either exposed (left) or not exposed (right) to 50 ng/mL VEGF for 15 minutes. VEGFR2 was then immunoprecipitated and the precipitates were analyzed by western blot with anti–SHP-1 antibody. Blots were reprobed with an antibody to VEGFR2. Blots are representative of 3 experiments.