Differential association of cellular proteins with family protein-tyrosine kinases.

We have sought to identify candidate substrates for src family protein-tyrosine kinases potentially important for transformation. Transfected NIH/3T3 cells, each overexpressing a normal or activated version of the fyn, fgr, or src translational product, were examined using antibody to phosphotyrosine as a probe. Expression of each cDNA induced similar but distinct patterns of tyrosine phosphorylated cellular proteins, with the extent of phosphorylation being greatest in cells expressing an activated kinase. A 70-kDa tyrosine-phosphorylated protein was found to associate with the activated fyn gene product. A protein designated p130, tyrosine phosphorylated in vitro, and in vivo, was found to physically associate with the activated product of each src family gene examined. Physical interaction of three different highly transforming tyrosine kinases with a common cellular protein suggests that p130 may play an important role in transformation induced by src family kinases.