Planta

, Volume 227, Issue 3, pp 659–669

The Arabidopsis cax3 mutants display altered salt tolerance, pH sensitivity and reduced plasma membrane H+-ATPase activity

Authors

  • Jian Zhao
    • United States Department of Agriculture/Agricultural Research Service Children’s Nutrition Research CenterBaylor College of Medicine
  • Bronwyn J. Barkla
    • Instituto de BiotecnologíaUniversidad Nacional Autónoma de México
  • Joy Marshall
    • Department of BiologyPrairie View A&M University
  • Jon K. Pittman
    • Faculty of Life SciencesUniversity of Manchester
    • United States Department of Agriculture/Agricultural Research Service Children’s Nutrition Research CenterBaylor College of Medicine
    • Vegetable and Fruit Improvement CenterTexas A&M University
Original Article

DOI: 10.1007/s00425-007-0648-2

Cite this article as:
Zhao, J., Barkla, B.J., Marshall, J. et al. Planta (2008) 227: 659. doi:10.1007/s00425-007-0648-2

Abstract

Perturbing CAX1, an Arabidopsis vacuolar H+/Ca2+ antiporter, and the related vacuolar transporter CAX3, has been previously shown to cause severe growth defects; however, the specific function of CAX3 has remained elusive. Here, we describe plant phenotypes that are shared among cax1 and cax3 including an increased sensitivity to both abscisic acid (ABA) and sugar during germination, and an increased tolerance to ethylene during early seedling development. We have also identified phenotypes unique to cax3, namely salt, lithium and low pH sensitivity. We used biochemical measurements to ascribe these cax3 sensitivities to a reduction in vacuolar H+/Ca2+ transport during salt stress and decreased plasma membrane H+-ATPase activity. These findings catalog an array of CAX phenotypes and assign a specific role for CAX3 in response to salt tolerance.

Keywords

ArabidopsisAntiporterCalciumSalt toleranceTransport

Abbreviations

35S

35S Cauliflower mosaic virus promoter

ABA

Abscisic acid

ACC

1-Aminocyclopropane-1-carboxylic acid

AHA

Arabidopsis H+-ATPase

CAX

Cation exchanger

MS

Murashige and Skoog medium

P-ATPase

Plasma membrane H+-ATPase

sCAX

N-terminal truncated cation exchanger

V-ATPase

Vacuolar-type H+-ATPase

Copyright information

© Springer-Verlag 2007