MX2 and HIV-1 infection: We next compared the MxB sensitivity profiles of the CA mutant viruses to similar profiles generated when HIV-1 infection was perturbed through other means, including restriction by TRIM5α or a truncated version of cleavage and polyadenylation specific factor (CPSF) 6 (CPSF6358), or by cell growth arrest (Figure 2E and F) [26].