Adhesive ligand binding to integrin (alpha)(IIb)(beta)(3) stimulates tyrosine phosphorylation of novel protein substrates before phosphorylation of pp125(FAK)

It was determined whether fibrinogen binding, per se, triggers a process of tyrosine phosphorylation in the absence of exogenous agonists. Results demonstrate that fibrinogen binding to alpha-IIb-beta-3 initiates a process of tyrosine phosphorylation that precedes platelet aggregation and the phosphorylation of pp125FAK.