title: HIV-1 assembly: viral glycoproteins segregate quantally to lipid rafts that associate individually with HIV-1 capsids and virions.
abstract: HIV-1 assembly depends on its structural protein, Gag, which after synthesis on ribosomes, traffics to the late endosome/plasma membrane, associates with HIV Env glycoprotein, and forms infectious virions. While Env and Gag migrate to lipid microdomains, their stoichiometry and specificity of interaction are unknown. Pseudotyped viral particles can be made with one viral core surrounded by heterologous envelope proteins. Taking advantage of this property, we analyzed the association of HIV Env and Ebola glycoprotein (GP), with HIV-1 Gag coexpressed in the same cell. Though both viral glycoproteins were expressed, each associated independently with Gag, giving rise to distinct virion populations, each with a single glycoprotein type. Confocal imaging demonstrated that Env and GP localized to distinct lipid raft microdomains within the same cell where they associated with different virions. Thus, a single Gag particle associates "quantally" with one lipid raft, containing homogeneous trimeric viral envelope proteins, to assemble functional virions.
authors.affiliation: Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, MD 20892-0485, USA.
authors.forename: Kwanyee
authors.initials: K
authors.lastname: Leung
authors.forename: Jae-Ouk
authors.initials: JO
authors.lastname: Kim
authors.forename: Lakshmanan
authors.initials: L
authors.lastname: Ganesh
authors.forename: Juraj
authors.initials: J
authors.lastname: Kabat
authors.forename: Owen
authors.initials: O
authors.lastname: Schwartz
authors.forename: Gary J
authors.initials: GJ
authors.lastname: Nabel
mesh_terms: D002213:Capsid / Q000378:metabolism; D002460:Cell Line; D005822:Genetic Vectors; D019302:HIV Envelope Protein gp160 / Q000378:metabolism; D015497:HIV-1 / Q000502:physiology*; D021962:Membrane Microdomains / Q000378:metabolism*; D008954:Models, Biological; D014759:Viral Envelope Proteins / Q000378:metabolism; D014771:Virion; D019065:Virus Assembly
chemical_list: D019302:HIV Envelope Protein gp160; D014759:Viral Envelope Proteins; C113189:envelope glycoprotein, Ebola virus