title: APOBEC3G targets specific virus species.
abstract: Human APOBEC3G (huAPOBEC3G), also known as CEM15, is a broad antiretroviral host factor that deaminates dC to dU in the minus strand DNA of human immunodeficiency virus type 1 (HIV-1), other lentiviruses, and murine leukemia virus (MLV), thereby creating G-to-A hypermutation in the plus strand DNA to inhibit the infectivity of these viruses. In this study, we examined the antiretroviral function of a murine homologue of APOBEC3G (muAPOBEC3G) on several retrovirus systems with different producer cells. MuAPOBEC3G did not suppress the infectivity of murine retroviral vectors produced from human or murine cells, whereas it showed antiviral activity on both wild-type and Deltavif virions of HIV-1 in human cells. In contrast, huAPOBEC3G showed broad antiviral activity on HIV-1 and murine retroviral vectors produced from human cells as well as murine cells. These data suggested that muAPOBEC3G does not possess antiretroviral activity on murine retroviruses and has a different target specificity from that of huAPOBEC3G and that huAPOBEC3G works as a broad antiviral factor not only in human cells but also in murine cells. A functional interaction study between human and murine APOBEC3G supported the former hypothesis. Furthermore, studies on the expression of APOBEC3G in producer cells and its incorporation into virions revealed that muAPOBEC3G is incorporated into HIV-1 virions but not into MLV virions. Thus, muAPOBEC3G cannot suppress the infectivity of murine retrovirus because it is not incorporated into virions. We suggest that murine retroviruses can replicate in murine target cells expressing muAPOBEC3G because they are not targets for this enzyme.
authors.affiliation: Department of Hematology and Oncology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Kobayashi
authors.forename: Akifumi
authors.initials: A
authors.lastname: Takaori-Kondo
authors.forename: Keisuke
authors.initials: K
authors.lastname: Shindo
authors.forename: Aierken
authors.initials: A
authors.lastname: Abudu
authors.forename: Keiko
authors.initials: K
authors.lastname: Fukunaga
authors.forename: Takashi
authors.initials: T
authors.lastname: Uchiyama
mesh_terms: D000071480:APOBEC-3G Deaminase; D000818:Animals; D000998:Antiviral Agents / Q000502:physiology*; D002460:Cell Line; D003564:Cytidine Deaminase; D015497:HIV-1 / Q000472:pathogenicity; D006801:Humans; D009052:Leukemia Virus, Murine / Q000472:pathogenicity; D051379:Mice; D009700:Nucleoside Deaminases; D011506:Proteins / Q000502:physiology*; D012097:Repressor Proteins; D013045:Species Specificity; D014771:Virion / Q000472:pathogenicity
chemical_list: D000998:Antiviral Agents; D011506:Proteins; D012097:Repressor Proteins; D009700:Nucleoside Deaminases; D000071480:APOBEC-3G Deaminase; C464924:APOBEC3G protein, human; D003564:Cytidine Deaminase