Molecular mechanisms of simian immunodeficiency virus SIV(agm) RNA encapsidation.
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.
Fu
William
W
HIV Drug Resistance Program, National Cancer Institute, 1 Frederick, MD 21702, USA.
Prasad
V V S P
VV
Chen
Jianbo
J
Nikolaitchik
Olga
O
Hu
Wei-Shau
WS
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
D015683:Gene Products, gag; D019590:Nucleocapsid Proteins; D012367:RNA, Viral