CD4 and HIV-1 infection: Figure 1B shows that Exo1 levels were depleted with kinetics similar to those seen for HLTF, in line with the data from primary CD4+ T cells. We conclude that HIV-1 infection depletes Exo1 levels in infected CD4+ T cells in a Vpr-dependent manner to an extent similar to that seen for previously validated targets of Vpr-CRL4DCAF1 E3.