The Nha1 antiporter of Saccharomyces cerevisiae mediates sodium and potassium efflux

• Published in: Microbiology (Society for General Microbiology) Vol. 144; no. 10; pp. 2749 - 2758
• Main Authors: BANUELOS, M. A, SYCHROVA, H, BLEYKASTEN-GROSSHANS, C, SOUCIET, J.-L, POTIER, S
• Format: Journal Article
• Language: English
• Published: Reading Society for General Microbiology 01.10.1998
• Subjects: Adenosine Triphosphatases - genetics; Adenosine Triphosphatases - metabolism; Antiporters - genetics; Antiporters - immunology; Antiporters - physiology; Biological and medical sciences; Blotting, Northern; Blotting, Western; Cation Transport Proteins; Cloning, Molecular; Drug Tolerance - genetics; Fundamental and applied biological sciences. Psychology; Fungal Proteins - genetics; Fungal Proteins - immunology; Fungal Proteins - physiology; Gene Deletion; Gene Expression - genetics; Genetic Vectors; Growth, nutrition, metabolism, transports, enzymes. Molecular biology; Homeostasis; Hydrogen-Ion Concentration; Ion Transport; Membrane Proteins - genetics; Membrane Proteins - immunology; Membrane Proteins - physiology; Microbiology; Mycology; Nha1p protein; Potassium - metabolism; Potassium-Hydrogen Antiporters; Promoter Regions, Genetic - genetics; Saccharomyces cerevisiae; Saccharomyces cerevisiae - drug effects; Saccharomyces cerevisiae - genetics; Saccharomyces cerevisiae - growth & development; Saccharomyces cerevisiae - metabolism; Saccharomyces cerevisiae Proteins; Salts - pharmacology; Sodium - metabolism; Sodium-Hydrogen Exchangers - genetics; Sodium-Hydrogen Exchangers - immunology; Sodium-Hydrogen Exchangers - physiology; Sodium-Potassium-Exchanging ATPase; Membrane protein; Yeast; Coupled transport; Gene expression; Fungi; Gene; Sodium; Membrane transport; Proton; Ascomycetes; Molecular cloning; Potassium; Saccharomyces cerevisiae; Thallophyta; Structural analysis
• ISSN: 1350-0872; 1465-2080
• DOI: 10.1099/00221287-144-10-2749

The NHA1 gene of Saccharomyces cerevisiae, transcribed into a 3.5 kb mRNA, encodes a protein mediating Na+ and K+ efflux through the plasma membrane that is required for alkali cation tolerance at acidic pH. Deletion of the gene in a wild-type strain resulted in higher sensitivity to both K+ and Na+ at acidic pH. Measurements of cation loss in strains carrying deleted or overexpressed alleles of NHA1 demonstrated its role in K+ and Na+ efflux. In addition, high K+ and Na+ efflux observed upon alkalinization of the cytoplasm implies a role of Nha1p in the regulation of intracellular pH. Moreover, the overexpression of ENA1 and NHA1 genes in an ena1-4 delta-nha1 delta strain showed that the Nha1 alkalication antiporter is responsible for growth on high concentrations of KCl and NaCl at acidic pH, and Ena alkali-cation ATPases are necessary at higher pH values. Both systems have a complementary action to maintain the intracellular steady-state concentration of K+ and Na+.