Functional conservation between yeast and plant endosomal Na+/H+ antiporters 1

FEBS Letters

Blatt, Michael R.¹  Pardo, José M.²  Quintero, Francisco J.² 

[1] Laboratory of Plant Physiology and Biophysics, University of London, Wye College, Wye TN25 5AH, UK;Instituto de Recursos Naturales y Agrobiologı́a, Consejo Superior de Investigaciones Cientı́ficas, P.O. Box 1052, Seville 41080, Spain

关键词: Sodium/proton antiporter;    Sodium compartmentation;    Halotolerance;    Arabidopsis thaliana;    Saccharomyces cerevisiae;   

DOI  :  10.1016/S0014-5793(00)01412-5

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Vacuolar compartmentation of Na⁺ is an essential mechanism for salinity tolerance since it lowers cytosolic Na⁺ levels while contributing to osmotic adjustment for cell turgor and expansion. The AtNHX1 protein of Arabidopsis thaliana substituted functionally for ScNHX1, the endosomal Na⁺/H⁺ antiporter of yeast. Ion tolerance conferred by AtNHX1 and ScNHX1 correlated with ion uptake into an intracellular pool that was energetically dependent on the vacuolar (H⁺)ATPase. AtNHX1 localized to vacuolar membrane fractions of yeast. Hence, both transporters share an evolutionarily conserved function in Na⁺ compartmentation. AtNHX1 mRNA levels were upregulated by ABA and NaCl treatment in leaf but not in root tissue.

【 授权许可】

Unknown