背景介绍
This gene is a member of the cytidine deaminase gene family. It is one of seven related genes or pseudogenes found in a cluster, thought to result from gene duplication, on chromosome 22. Members of the cluster encode proteins that are structurally and functionally related to the C to U RNA-editing cytidine deaminase APOBEC1. It is thought that the proteins may be RNA editing enzymes and have roles in growth or cell cycle control. Alternatively spliced transcript variants encoding different isoforms have been identified. [provided by RefSeq, Jul 2008],
功能
cofactor:Zinc.,function:After being packaged into HIV-1 virions, blocks productive infection by massively editing dC residues to dU on the DNA minus strand during reverse transcription. The editing of the minus strand DNA of HIV-1 during reverse transcription leads to G-to-A transitions in the plus strand. The inhibition of viral replication is either due to the degradation of the minus strand before its integration or to the lethality of the hypermutations.,function:DNA deaminase (cytidine deaminase) that mediates a form of innate resistance to retroviral infections (at least to HIV-1 infection) by triggering G-to-A hypermutation in the newly synthesized viral DNA. The replacements C-to-U in the minus strand DNA of HIV-1 during reverse transcription, leads to G-to-A transitions in the plus strand. The inhibition of viral replication is either due to the degradation of the minus strand before its integration or to the lethality of the hypermutations. Modification of both DNA strands is not excluded. This antiviral activity is neutralized by the virion infectivity factor (VIF), that prevents the incorporation of APOBEC3G into progeny HIV-1 virions by both inhibiting its translation and/or by inducing its ubiquitination and subsequent degradation by the 26S proteasome. APOBEC3G binds a variety of RNAs, but does not display detectable APOB, NF1 and NAT1 mRNA editing.,miscellaneous:Accumulation of APOBEC3G induced non-lethal hypermutation could contribute to the genetic variation of primate lentiviral populations.,miscellaneous:HIV-1 does not replicate productively in non-human primates with the exception of the chimpanzee. The primates APOBEC3G (rhesus macaque, chimpanzee and African green monkey) are active against HIV-1 without VIF. Only the chimpanzee APOBEC3G is inhibited by HIV-1 VIF.,miscellaneous:Inhibits also the infectivity of retroviral particles only distantly related to HIV-1, such as the simian immunodeficiency virus (SIV), the equine infectious anemia virus (EIAV) and the murine leukemia virus (MLV).,miscellaneous:It is one of seven related genes or pseudogenes found in a cluster, thought to result from gene duplication, on chromosome 22.,online information:Protein wars - Issue 45 of April 2004,PTM:Ubiquitinated in the presence of HIV-1 VIF. Association with VIF targets the protein for proteolysis by the ubiquitin-dependent proteasome pathway.,similarity:Belongs to the cytidine and deoxycytidylate deaminase family.,subcellular location:Mainly cytoplasmic. Small amount are found in the nucleus. During HIV-1 infection, virion-encapsidated in absence of HIV-1 VIF.,subunit:Forms heterodimers with APOBEC3G. Binds HIV-1 Vif. In the absence of Vif protein, specifically packaged into HIV-1 virions.,subunit:Homodimer. Interacts with APOBEC3B, APOBEC3F and HIV-1 VIF in a species specific manner.,tissue specificity:Expressed in spleen, testes, ovary and peripheral blood leukocytes and CD4+ lymphocytes. Also expressed in non-permissive peripheral blood mononuclear cells, and several tumor cell lines; no expression detected in permissive lymphoid and non-lymphoid cell lines.,tissue specificity:Widely expressed, including in lymphoid tissues, such as thymus and peripheral blood leukocytes. No expression detected in permissive lymphoid.,
