FIG. 7.

Analysis of single-site “pocket” mutants of c-Src. (A) COS-1 cells transfected with WT and mutant c-Src constructs were lysed at 22 or 48 h posttransfection, and lysates were analyzed by Western blotting with the indicated antibodies. (B) COS-1 cells transfected with WT or mutant c-Src were lysed at 24 h posttransfection. c-Src was immunoprecipitated and used in an in vitro kinase assay with purified Cas. Representative data from two independent experiments performed in duplicate are shown. The inset shows that equal amounts of WT and mutant Src were immunoprecipitated. (C) COS-1 cells transfected with the indicated c-Src constructs were labeled with the myristate analog 13-[¹²⁵I]iodotridecanoic acid for 4 h at 37°C. c-Src was immunoprecipitated, and radiolabel incorporation was analyzed by SDS-PAGE and autoradiography. (D) Lysates from COS-1 cells cotransfected with NMT and WT or mutant c-Src were subjected to cell fractionation and analyzed as described in the legend to Fig. 1C.