title: Functional production of mammalian concentrative nucleoside transporters in Saccharomyces cerevisiae.
abstract: The transport of nucleosides and nucleobases in the yeast Saccharomyces cerevisiae is reviewed and the use of this organism to study recombinant mammalian concentrative nucleoside transport (CNT) proteins is described. A selection strategy based on the ability of an expressed nucleoside transporter cDNA to mediate thymidine uptake by yeast under a selective condition that depletes endogenous thymidylate was used to assess the transport capacity of heterologous transporter proteins. The pyrimidine-nucleoside selective concentrative transporters from human (hCNT1) and rat (rCNT1) complemented the imposed thymidylate depletion in S. cerevisiae, as did N-terminally truncated versions of hCNT1 and rCNT1 lacking up to 31 amino acids. Transporter-mediated rescue of S. cerevisiae by both nucleoside transporters was inhibited by cytidine, uridine and adenosine, but not by guanosine or inosine. This work represents the development of a new model system for the functional production of recombinant nucleoside transporters of the CNT family of membrane proteins.
authors.affiliation: University of Alberta, and Cross Cancer Institute, Edmonton, Canada.
authors.forename: M F
authors.initials: MF
authors.lastname: Vickers
authors.forename: J D
authors.initials: JD
authors.lastname: Young
authors.forename: S A
authors.initials: SA
authors.lastname: Baldwin
authors.forename: M J
authors.initials: MJ
authors.lastname: Ellison
authors.forename: C E
authors.initials: CE
authors.lastname: Cass
mesh_terms: D000818:Animals; D001692:Biological Transport; D018076:DNA, Complementary / Q000378:metabolism; D005816:Genetic Complementation Test; D006801:Humans; D026901:Membrane Transport Proteins / Q000378:metabolism*; D033702:Nucleobase Transport Proteins; D033703:Nucleoside Transport Proteins; D009705:Nucleosides / Q000378:metabolism*; D033704:Nucleotide Transport Proteins; D051381:Rats; D011994:Recombinant Proteins / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism
chemical_list: D018076:DNA, Complementary; C043181:FCY2 protein, S cerevisiae; C413444:FUI1 protein, S cerevisiae; C035528:FUR4 protein, S cerevisiae; D026901:Membrane Transport Proteins; D033702:Nucleobase Transport Proteins; D033703:Nucleoside Transport Proteins; D009705:Nucleosides; D033704:Nucleotide Transport Proteins; D011994:Recombinant Proteins; D029701:Saccharomyces cerevisiae Proteins; C065171:cif nucleoside transporter