title: Distinct domains within APOBEC3G and APOBEC3F interact with separate regions of human immunodeficiency virus type 1 Vif.
abstract: Human APOBEC3G (A3G) and APOBEC3F (A3F) inhibit the replication of Vif-deficient human immunodeficiency virus type 1 (HIV-1). HIV-1 Vif overcomes these host restriction factors by binding to them and inducing their degradation. Thus, the Vif-A3G and Vif-A3F interactions are attractive targets for antiviral drug development, as inhibiting these interactions could allow the host defense mechanism to control HIV-1 replication. Recently, it has been reported that amino acids 105 to 156 of A3G are involved in the interaction with Vif; however, to date, the region of A3F involved in Vif binding has not been identified. Using our previously reported Vif mutants that are capable of binding to only A3G (3G binder) or only A3F (3F binder), in conjunction with a series of A3G-A3F chimeras, we have now mapped the APOBEC3-Vif interaction domains. We found that the A3G domain that interacts with the Vif YRHHY region is located between amino acids 126 and 132 of A3G, which is consistent with the conclusions reported in previous studies. The A3F domain that interacts with the Vif DRMR region did not occur in the homologous domain but instead was located between amino acids 283 and 300 of A3F. These studies are the first to identify the A3F domain that interacts with the Vif DRMR region and show that distinct domains of A3G and A3F interact with different Vif regions. Pharmacological inhibition of either or both of these Vif-A3 interactions should prevent the degradation of the APOBEC3 proteins and could be used as a therapy against HIV-1.
authors.affiliation: Viral Mutation Section, HIV Drug Resistance Program, Center for Cancer Research, National Cancer Institute at Frederick, Frederick, Maryland 21702, USA.
authors.forename: Rebecca A
authors.initials: RA
authors.lastname: Russell
authors.forename: Jessica
authors.initials: J
authors.lastname: Smith
authors.forename: Rebekah
authors.initials: R
authors.lastname: Barr
authors.forename: Darshana
authors.initials: D
authors.lastname: Bhattacharyya
authors.forename: Vinay K
authors.initials: VK
authors.lastname: Pathak
mesh_terms: D000071480:APOBEC-3G Deaminase; D000595:Amino Acid Sequence; D002460:Cell Line; D003564:Cytidine Deaminase / Q000378:metabolism*; D043525:Cytosine Deaminase / Q000378:metabolism*; D015497:HIV-1 / Q000502:physiology*; D006801:Humans; D008969:Molecular Sequence Data; D050505:Mutant Proteins / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D025941:Protein Interaction Mapping; D054320:vif Gene Products, Human Immunodeficiency Virus / Q000235:genetics / Q000378:metabolism*
chemical_list: D050505:Mutant Proteins; D054320:vif Gene Products, Human Immunodeficiency Virus; C514847:vif protein, Human immunodeficiency virus 1; C492906:APOBEC3F protein, human; D043525:Cytosine Deaminase; D000071480:APOBEC-3G Deaminase; C464924:APOBEC3G protein, human; D003564:Cytidine Deaminase