title: A vacuolar membrane protein Avt7p is involved in transport of amino acid and spore formation in Saccharomyces cerevisiae.
abstract: Active transport systems for various amino acids operate in the vacuolar membrane of Saccharomyces cerevisiae. The gene families for vacuolar amino acid transporters were identified by reverse genetics experiments. In the AVT transporter family, Avt1p works for active uptake of amino acid into vacuole, and Avt3p, Avt4p, and Avt6p for active extrusion of amino acid from vacuole to cytosol. Here, we found green fluorescent protein-tagged Avt7p, an unidentified member of the AVT family, localized to the vacuolar membrane of S. cerevisiae. Disruption of the AVT7 gene enhanced both vacuolar contents of several amino acids and uptake activities of glutamine and proline by vacuolar membrane vesicles. Efficiency of spore formation was impaired by the disruption of the AVT7 gene, suggesting the physiological importance of Avt7p-dependent efflux of amino acid from vacuoles under nutrient-poor condition.
authors.affiliation: a Laboratory of Molecular Physiology and Genetics, Faculty of Agriculture , Ehime University , Matsuyama , Japan.
authors.forename: Junichi
authors.initials: J
authors.lastname: Tone
authors.forename: Atsushi
authors.initials: A
authors.lastname: Yamanaka
authors.forename: Kunio
authors.initials: K
authors.lastname: Manabe
authors.forename: Nami
authors.initials: N
authors.lastname: Murao
authors.forename: Miyuki
authors.initials: M
authors.lastname: Kawano-Kawada
authors.forename: Takayuki
authors.initials: T
authors.lastname: Sekito
authors.forename: Yoshimi
authors.initials: Y
authors.lastname: Kakinuma
mesh_terms: D026921:Amino Acid Transport Systems, Neutral / Q000378:metabolism*; D000596:Amino Acids / Q000378:metabolism*; D007425:Intracellular Membranes / Q000378:metabolism; D009584:Nitrogen / Q000172:deficiency; D021381:Protein Transport; D012441:Saccharomyces cerevisiae / Q000166:cytology* / Q000378:metabolism* / Q000502:physiology; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*; D013172:Spores, Fungal / Q000502:physiology*; D014617:Vacuoles / Q000378:metabolism
chemical_list: D026921:Amino Acid Transport Systems, Neutral; D000596:Amino Acids; C000603331:Avt7 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D009584:Nitrogen
keywords: amino acid; extrusion; spore; starvation; vacuole