SH2 domain of Src binds to the active receptor

The Src family of tyrosine kinases are characterized by a SH3 and a SH2 domain in addition to the kinase domain.Src is activated when the SH2 domain binds to autophosphorylation sites on PDGF receptors (Tyr579 and 581 in the beta-receptor, Tyr572 and 574 in the alpha receptor), in conjuction with dephosporylation of the COOH-terminal phosphorylated tyrosine 527.

Src家族的酪氨酸激酶以其激酶结构域之外，还具备SH3和SH2结构域为特征。Src激酶在SH2结构域与PDGF受体上的自磷酸化位点（β受体中的Tyr579和Tyr581，α受体中的Tyr572和Tyr574）结合，并与COOH末端磷酸化酪氨酸527的去磷酸化协同作用时被激活。