DNA dC->dU-editing enzyme APOBEC-3B (APOBEC3B)

DNA deaminase (cytidine deaminase) which acts as an inhibitor of retrovirus replication and retrotransposon freedom via deaminase-dependent and -independent mechanisms. Following the penetration of retroviral nucleocapsids into target cells of disease and the initiation of reverse transcription, it can induce the conversion of cytosine to uracil in the minus-sense single-strand viral DNA, resulting in G-to-A hypermutations in the subsequent plus-strand viral DNA.

The resultant detrimental levels of mutations from the proviral genome, along with a deamination- independent mechanism that operates before the proviral integration, together exert efficient antiretroviral effects in infected cells. Selectively targets single-stranded DNA and does not deaminate double-stranded DNA or single-or double- stranded RNA.