Figure 4.

Effect of wild-type and dominant negative E6AP on the degradation of activated Blk. Blk was transfected into Cos-7 cells with wild-type or C833A forms of E6AP, the catalytically inactive form (C/A mutant) of the rat p100 E3, or empty vector. Forty hours after transfection, cells were treated with increasing concentrations of pervanadate for 2 hr. Total cell lysates were subjected to immunoblot analysis for Blk (A). Specific signals (arrow heads) were quantitated by densitometry, and the percent Blk remaining at each concentration of pervanadate was compared with the nontreated levels (B).