CUL4A and infection: The partial reduction in DCAF1 levels did not affect the infection of the HIV-1 Vpr+ and HIV-1 Vpr+ (Fig. 6A and 6B), suggesting that the Vpr-mediated enhancement of infection in HuT/CCR5 cells did not involve the recruitment of the DCAF1/DDB1/Cul4A complex and proteasomal degradation.