The Nha1 antiporter of Saccharomyces cerevisiae mediates sodium and potassium efflux

Microbiology (Reading). 1998 Oct:144 ( Pt 10):2749-2758. doi: 10.1099/00221287-144-10-2749.

Abstract

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+.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphatases / genetics
  • Adenosine Triphosphatases / metabolism
  • Antiporters / genetics
  • Antiporters / immunology
  • Antiporters / physiology*
  • Blotting, Northern
  • Blotting, Western
  • Cation Transport Proteins*
  • Cloning, Molecular
  • Drug Tolerance / genetics
  • Fungal Proteins / genetics
  • Fungal Proteins / immunology
  • Fungal Proteins / physiology
  • Gene Deletion
  • Gene Expression / genetics
  • Genetic Vectors
  • Homeostasis
  • Hydrogen-Ion Concentration
  • Ion Transport
  • Membrane Proteins / genetics
  • Membrane Proteins / immunology
  • Membrane Proteins / physiology*
  • Potassium / metabolism*
  • Potassium-Hydrogen Antiporters
  • Promoter Regions, Genetic / genetics
  • 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

Substances

  • Antiporters
  • Cation Transport Proteins
  • ENA1 protein, S cerevisiae
  • Fungal Proteins
  • Membrane Proteins
  • NHA1 protein, S cerevisiae
  • Potassium-Hydrogen Antiporters
  • Saccharomyces cerevisiae Proteins
  • Salts
  • Sodium-Hydrogen Exchangers
  • Sodium
  • Adenosine Triphosphatases
  • Sodium-Potassium-Exchanging ATPase
  • Potassium