APOBEC3C and infection: While the APOBEC3C I188 restricted 5–10 fold better than APOBEC3C S188 (Fig 6A: 60% infectivity compared to 8% infectivity), strikingly, APOBEC3C S188-S188 dimer restricted infection as efficiently as APOBEC3G (Fig 5B: approximately 1% infectivity for both conditions).