Functional expression of the ENA1(PMR2)-ATPase of Saccharomyces cerevisiae in Schizosaccharomyces pombe.
Na+ efflux and Na+ tolerance depend on a putative P-type ATPase encoded by the gene ENA1(PMR2) in Saccharomyces cerevisiae and on a putative Na+/H+ antiporter encoded by the gene sod2 in Schizosaccharomyces pombe. This report shows that a sod2::ura4 mutant of S. pombe transformed with the ENA1 gene of S. cerevisiae expressed the ENA1 protein, and recovered Na+ efflux and Na+ tolerance. The efflux of Na+ in the wild strain of S. pombe was sensitive to the transmembrane Na+ and H+ gradients, whereas in the sod2::ura4 mutant transformed with ENA1 it was independent of these gradients. The data give further support to the notion that ENA1 and sod2 encode Na+ transporters and not regulators of the process of Na+ export; they show also the physiological consequences of exporting Na+ through an Na(+)-ATPase or an Na+/H+ antiporter.
Bañuelos
M A
MA
Departamento de Microbiología, Escuela Técnica Superior de Ingenieros Agrónomos, Madrid, Spain.
Quintero
F J
FJ
Rodríguez-Navarro
A
A
D000251:Adenosine Triphosphatases / Q000235:genetics*; D001692:Biological Transport; D027682:Cation Transport Proteins; D003001:Cloning, Molecular; D006863:Hydrogen-Ion Concentration; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins; D012568:Schizosaccharomyces / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D012964:Sodium / Q000378:metabolism; D000254:Sodium-Potassium-Exchanging ATPase
D027682:Cation Transport Proteins; C086375:ENA1 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D012964:Sodium; D000251:Adenosine Triphosphatases; D000254:Sodium-Potassium-Exchanging ATPase