Figure 4.

c-Src elevates phosphorylation and self-ubiquitylation of c-Cbl. (A and B) SYF cells were transfected with plasmids encoding the indicated HA-tagged forms of c-Cbl, together with a plasmid encoding Y529F-Src, or the respective empty plasmid. Forty-eight hours after transfection, cell extracts were analyzed as indicated. (C) SYF cells were transfected with plasmids encoding EGFR and a Flag-tagged ubiquitin, along with the indicated forms of Src and Cbl. Forty-eight hours after transfection, cells were untreated or treated for 15 min with EGF (100 ng/ml), and cell extracts were analyzed as indicated. IP, immunoprecipitation; IB, immunoblotting.