SH3 And PX Domain Containing Protein 2A (SH3PXD2A)

A new method for isolating tyrosine kinase substrates used to identify fish, an SH3 and PX domain-containing protein, and Src substrate.

Several potential Src substrates were identified including Fish, which has five SH3 domains and a recently discovered phox homology (PX) domain. Fish is tyrosine-phosphorylated in Src-transformed fibroblasts (suggesting that it is a target of Src in vivo) and in normal cells following treatment with several growth factors. Treatment of cells with cytochalasin D also resulted in rapid tyrosine phosphorylation of Fish, concomitant with activation of Src. These data suggest that Fish is involved in signalling by tyrosine kinases, and imply a specialized role in the actin cytoskeleton.