Aquaporins in Saccharomyces

• Published in: The Journal of biological chemistry Vol. 273; no. 42; pp. 27565 - 27572
• Main Authors: Bonhivers, Mélanie, Carbrey, Jennifer M., Gould, Stephen J., Agre, Peter
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 16.10.1998; American Society for Biochemistry and Molecular Biology
• Subjects: ABSORCION DE AGUA; ABSORPTION D'EAU; ACTIVE TRANSPORT; AGUA; AGY1 GENE; AMINO ACID SEQUENCES; AMPHIBIANS; AMPHIBIEN; ANFIBIOS; BIOLOGICAL DIFFERENCES; CELL MEMBRANES; CHEMICAL COMPOSITION; COMPOSICION QUIMICA; COMPOSITION CHIMIQUE; DIFERENCIAS BIOLOGICAS; DIFFERENCE BIOLOGIQUE; EAU; EXPRESION GENICA; EXPRESSION DES GENES; GENBANK/AF053981; GENE; GENE EXPRESSION; GENE TRANSFER; GENES; LABORATORY STRAINS; MEMBRANAS CELULARES; MEMBRANE CELLULAIRE; MOLECULAR SEQUENCE DATA; NUCLEOTIDE SEQUENCE; OOCYTES; OPEN READING FRAMES; OVA; OVULE; OVULO; PLASMA MEMBRANES; PROTEINAS; PROTEINE; PROTEINS; SACCHAROMYCES CEREVISIAE; SECUENCIA NUCLEOTIDICA; SEQUENCE NUCLEOTIDIQUE; STRAIN DIFFERENCES; STRAINS; STRUCTURAL GENES; TRANSFERENCIA DE GENES; TRANSFERT DE GENE; WATER; WATER UPTAKE; WILD STRAINS; XENOPUS LAEVIS
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1074/jbc.273.42.27565

Aquaporin water channel proteins mediate the transport of water across cell membranes in numerous species. TheSaccharomyces genome data base contains an open reading frame (here designated AQY1) that encodes a protein with strong homology to aquaporins. AQY1 from laboratory and wild-type strains of Saccharomyces were expressed in Xenopus oocytes to determine the coefficients of osmotic water permeability (Pf). Oocytes injected with wild-typeAQY1 cRNAs exhibit high Pf values, whereas oocytes injected with AQY1 cRNAs from laboratory strains exhibit low Pf values and have reduced levels of Aqy1p due to two amino acid substitutions. When the AQY1 gene was deleted from a wild-type yeast and cells were cultured in vitro with cycled hypo-osmolar or hyper-osmolar stresses, theAQY1 null yeast showed significantly improved viability when compared with the parental wild-type strain. We conclude thatSaccharomyces cerevisiae contains at least one aquaporin gene, but it is not functional in laboratory strains due to apparent negative selection pressures resulting from in vitromethods.