Figure 4.

Platelet aggregation results in the formation of Fyn and Lyn complexes with EphA4. Platelets were incubated with ADP (20 μM) under conditions that allowed aggregation to occur. After 5 min, the cells were lysed and EphA4 was immunoprecipitated. The precipitates were then subjected to electrophoresis and probed with antibodies to Fyn, Lyn, or Src. Where indicated, Eph/ephrin interactions were blocked with a combination of His-EphA4 plus His-EphB1 at a final concentration of 10 μg/ml of each, a concentration found to be sufficient to block ephrin/Eph kinase interactions (58, 59). The lane farthest to the right shows total platelet lysates probed with a Src-specific antibody to document that Src is present. IP, the immunoprecipitating antibody; IB, the antibody used in the Western immunoblot.