DNA dC->dU-editing enzyme APOBEC-3H (APOBEC3H)

DNA deaminase (cytidine deaminase) which functions as an inhibitor of retrovirus replication and retrotransposon mobility via deaminase-dependent and -independent mechanisms. The A3H- var/haplotype 2 exhibits antiviral activity against vif-deficient HIV-1.

After the penetration of retroviral nucleocapsids into target cells of infection 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 consequent detrimental levels of mutations from the proviral genome, along with a deamination-independent mechanism which works prior to the proviral integration, together exert effective antiretroviral effects in infected target cells.