APOBEC3G, DNA dC->dU-editing enzyme APOBEC-3G
Enzyme Classification 3.5.4.-
Also Known as
DNA deaminase (cytidine deaminase) which acts as an inhibitor of retrovirus replication and retrotransposon mobility via deaminase-dependent and -independent mechanisms. Exhibits potent 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, leading to G-to-A hypermutations in the subsequent plus-strand viral DNA. The resultant detrimental levels of mutations in the proviral genome, along with a deamination-independent mechanism that works prior to the proviral integration, together exert efficient antiretroviral effects in infected target cells. Selectively targets single-stranded DNA and does not deaminate double-stranded DNA or single-or double-stranded RNA. Exhibits antiviral activity also against simian immunodeficiency viruses (SIVs), hepatitis B virus (HBV), equine infectious anemia virus (EIAV), xenotropic MuLV-related virus (XMRV) and simian foamy virus (SFV). May inhibit the mobility of LTR and non-LTR retrotransposons. Homodimer. Homooligomer. Can bind RNA to form ribonucleoprotein complexes of high-molecular-mass (HMM) or low-molecular-mass (LMM). HMM is inactive and heterogeneous in protein composition because of binding nonselectively to cellular RNAs, which in turn are associated with variety of cellular proteins. The LMM form which is enzymatically active has few or no RNAs associated. Its ability to form homooligomer is distinct from its ability to assemble into HMM. Interacts with APOBEC3B, APOBEC3F, MOV10, AGO2, EIF4E, EIF4ENIF1, DCP2 and DDX6 in an RNA-dependent manner. Interacts with AGO1, AGO3 and PKA/PRKACA.