Maintenance of proper intracellular concentrations of monovalent cations, mainly sodium and potassium, is a requirement for survival of any cell. In the budding yeast Saccharomyces cerevisiae, monovalent cation homeostasis is determined by the active extrusion of protons through the Pma1 H+ -ATPase (reviewed in another chapter of this issue), the influx and efflux of these cations through the plasma membrane transporters (reviewed in this chapter), and the sequestration of toxic cations into the vacuoles. Here, we will describe the structure, function, and regulation of the plasma membrane transporters Trk1, Trk2, Tok1, Nha1, and Ena1, which play a key role in maintaining physiological intracellular concentrations of Na+ , K+ , and H+ , both under normal growth conditions and in response to stress.

Departamento de Microbiología Universidad de Córdoba Córdoba Spain

Department of Membrane Transport Institute of Physiology Czech Academy of Sciences Prague Czech Republic

Institut de Biotecnologia i Biomedicina and Departament de Bioquimica i Biologia Molecular Universitat Autònoma de Barcelona Cerdanyola del Vallès Spain

References provided by Crossref.org

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