FIG 2.
CBF-β is critical for the primary HIV-1 Vif-Cul5 interaction. CBF-β is important for HIV-189.6 Vif-mediated (A) and HIV-1Yu2 Vif-mediated (D) degradation of human A3G. HEK293T cells were transfected with expression vectors for HIV-189.6 Vif-HA (B) or HIV-1Yu2 Vif-HA (E) in the presence of control shRNA (lane 1) or shRNA against CBF-β (lane 2). After 36 h, cells were lysed, and the supernatant was immunoprecipitated (IP) and analyzed by immunoblotting as described in Materials and Methods (lanes 3 and 4). Coimmunoprecipitated Cul5 protein bands with HIV-189.6 Vif (B, lanes 3 and 4) and HIV-1Yu2 Vif (E, lanes 3 and 4) were quantified as previously described (51) and shown in panel C and F, respectively. Coimmunoprecipitated Cul5 from control cells was set to 100%. The data shown represent one of three independent experiments. Error bars represent the standard deviation of the mean of triplicate samples. EloB, ElonginB; Con, control.