title: Features of the Env leader protein and the N-terminal Gag domain of feline foamy virus important for virus morphogenesis.
abstract: Previous studies have shown that foamy virus (FV) particle budding, especially the involvement of the viral env glycoprotein is different from that of other (ortho) retroviruses: the N-terminal Env leader protein Elp is a constituent of released FV particles. A defined sequence in Elp required for particle budding binds to the MA domain of Gag. To extend these findings, we show that feline FV Elp is a membrane-anchored protein with the N-terminus located inside the particle. Thus, the internal/cytoplasmic domain of Elp has the correct topology for interacting with Gag during budding. In addition to Elp, an Elp-related protein of about 9 kDa was shown to be virion associated and is probably generated by cellular signal peptidases. Besides the function of Elp binding, the N-terminal domain of Gag was shown to be required for proper localization of feline FV Gag to the cytoplasm and the perinuclear/nuclear region.
authors.affiliation: Abteilung Retrovirale Genexpression, Forschungsschwerpunkt Angewandte Tumorvirologie, Deutsches Krebsforschungszentrum, Heidelberg, Germany.
authors.forename: Verena
authors.initials: V
authors.lastname: Geiselhart
authors.forename: Astrid
authors.initials: A
authors.lastname: Schwantes
authors.forename: Patrizia
authors.initials: P
authors.lastname: Bastone
authors.forename: Matthias
authors.initials: M
authors.lastname: Frech
authors.forename: Martin
authors.initials: M
authors.lastname: Löchelt
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D019084:Fluorescent Antibody Technique, Indirect; D015686:Gene Products, env / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D015683:Gene Products, gag / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D006801:Humans; D015151:Immunoblotting; D008969:Molecular Sequence Data; D009154:Mutation; D011485:Protein Binding; D013045:Species Specificity; D016092:Spumavirus / Q000235:genetics / Q000502:physiology*; D013347:Subcellular Fractions / Q000378:metabolism; D014162:Transfection; D014771:Virion / Q000378:metabolism / Q000502:physiology*; D019065:Virus Assembly
chemical_list: D015686:Gene Products, env; D015683:Gene Products, gag