title: Molecular mechanisms of simian immunodeficiency virus SIV(agm) RNA encapsidation.
abstract: Primate lentiviruses are composed of several distinct lineages, including human immunodeficiency virus type 1 (HIV-1), HIV-2, and simian immunodeficiency virus SIVagm. HIV-1 and HIV-2 have significant differences in the mechanisms of viral RNA encapsidation. Therefore, the RNA packaging mechanisms of SIVagm cannot be predicted from the studies of HIV-1 and HIV-2. We examined the roles of the nucleocapsid (NC) zinc finger motifs on RNA packaging by mutating the conserved zinc finger (CCHC) motifs, and whether SIVagm has a preference to package RNA in cis by comparing the RNA packaging efficiencies of gag mutants in the presence of a wild-type vector. Our results indicate that the SIVagm NC domain plays an important role in Gag-RNA recognition; furthermore SIVagm is distinct from the other currently known primate lentiviruses as destroying either zinc finger motif in the NC causes very drastic RNA packaging defects. Additionally, trans-packaging is a major mechanism for SIVagm RNA encapsidation.
authors.affiliation: HIV Drug Resistance Program, National Cancer Institute, 1 Frederick, MD 21702, USA.
authors.forename: William
authors.initials: W
authors.lastname: Fu
authors.forename: V V S P
authors.initials: VV
authors.lastname: Prasad
authors.forename: Jianbo
authors.initials: J
authors.lastname: Chen
authors.forename: Olga
authors.initials: O
authors.lastname: Nikolaitchik
authors.forename: Wei-Shau
authors.initials: WS
authors.lastname: Hu
mesh_terms: D002460:Cell Line; D015683:Gene Products, gag / Q000378:metabolism; D006801:Humans; D009154:Mutation / Q000235:genetics; D019590:Nucleocapsid Proteins / Q000235:genetics / Q000378:metabolism; D012367:RNA, Viral / Q000235:genetics / Q000378:metabolism*; D015302:Simian Immunodeficiency Virus / Q000145:classification / Q000235:genetics* / Q000378:metabolism*; D019065:Virus Assembly / Q000235:genetics; D014779:Virus Replication / Q000235:genetics
chemical_list: D015683:Gene Products, gag; D019590:Nucleocapsid Proteins; D012367:RNA, Viral