APOBEC3 proteins are important cellular factors that restrict infection by a number of viruses, including human immunodeficiency virus type 1 (HIV-1). Previously, we found that the mouse APOBEC3 (mA3) restricts infection by mouse mammary tumor virus (MMTV) in its natural host. Dendritic cells (DCs) are the first in vivo targets of MMTV infection. In this study, we demonstrate that mA3 expressed...

The APOBEC3 proteins are unique to mammals. Many inhibit retrovirus infection through a cDNA cytosine deamination mechanism. HIV-1 neutralizes this host defense through Vif, which triggers APOBEC3 ubiquitination and degradation. Here, we report an APOBEC3F-like, double deaminase domain protein from three artiodactyls: cattle, pigs and sheep. Like their human counterparts, APOBEC3F and APOBEC3G,...

The human genome encodes numerous enzymes capable of deaminating polynucleotides. While they are capable of exquisite specificity, occasionally they result in hypermutation where up to 90 per cent of cytidine or adenosine residues may be edited. As such, they constitute a formidable anti-viral barrier, for no virus can survive such a high mutation rate. As the APOBEC3 group of cytidine deaminas...

The APOBEC3 family of mammalian cytidine deaminases, including APOBEC3G (A3G), has been shown to function as innate antiviral factors against retroviruses and can also suppress the replication of the hepatitis B virus (HBV). The mechanism by which A3G inhibits HBV replication remains to be elucidated. In this study, we show that the inhibitory effect of APOBEC3 proteins on HBV replication was m...

The human APOBEC3 (A3A-A3H) locus encodes six cytidine deaminases that edit single-stranded DNA, the result being DNA peppered with uridine. Although several cytidine deaminases are clearly restriction factors for retroviruses and hepadnaviruses, it is not known if APOBEC3 enzymes have roles outside of these settings. It is shown here that both human mitochondrial and nuclear DNA are vulnerable...

IFNα, a cytokine with multiple functions in innate and adaptive immunity and a potent inhibitor of HIV, exerts antiviral activity, in part, by enhancing apolipoprotein B mRNA-editing enzyme-catalytic polypeptide-like 3 (APOBEC3) family members. Although IFNα therapy is associated with reduced viral burden, this cytokine also mediates immune dysfunction and toxicities. Through detailed mapping o...

The human genome encodes numerous enzymes capable of deaminating polynucleotides. While they are capable of exquisite specificity, occasionally they result in hypermutation where up to 90 per cent of cytidine or adenosine residues may be edited. As such, they constitute a formidable anti-viral barrier, for no virus can survive such a high mutation rate. As the APOBEC3 group of cytidine deaminas...

Interferon (IFN) has been part of the standard treatment of chronic hepatitis B infection for more than 2 decades, yet the mechanism of action of this antiviral remains poorly understood. It was recently observed that members of the human APOBEC family of cytidine deaminases endowed with anti-hepatitis B virus (HBV) activity are upregulated by type I and II IFNs. However, we demonstrated that, ...