FIG. 6.

Activation of Src kinases upon HIV Tat stimulation. Total-cell lysates (500 μg) from unstimulated or HIV Tat-stimulated cell lysates were immunoprecipitated (IP) with anti-Src antibody. The immune complexes were subjected to Western blotting (WB) with antiphosphotyrosine antibody (top) followed by c-Src antibody (bottom) (A) or an in vitro kinase assay with enolase as the substrate. The ³²P-incorporated proteins were resolved by SDS-PAGE (7.5% polyacrylamide) followed by autoradiography. Control lane represents immunoprecipitates of antibody alone, and TCL lane represents 50 μg of total-cell lysates. MW, molecular weight in thousands. P-TYR, phosphotyrosine.