JXB Advance Access originally published online on March 2, 2006
Journal of Experimental Botany 2006 57(5):1181-1199; doi:10.1093/jxb/erj114
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
RESEARCH PAPER |
Alkali cation exchangers: roles in cellular homeostasis and stress tolerance
Instituto de Recursos Naturales y Agrobiología, Consejo Superior de Investigaciones Científicas, Reina Mercedes 10, Sevilla 41012, Spain
* To whom correspondence should be addressed. E-mail: pardo{at}cica.es
Uptake and translocation of cations play essential roles in plant nutrition, signal transduction, growth, and development. Among them, potassium (K+) and sodium (Na+) have been the focus of numerous physiological studies because K+ is an essential macronutrient and the most abundant inorganic cation in plant cells, whereas Na+ toxicity is a principal component of the deleterious effects associated with salinity stress. Although the homeostasis of these two ions was long surmised to be fine tuned and under complex regulation, the myriad of candidate membrane transporters mediating their uptake, intracellular distribution, and long-distance transport is nevertheless perplexing. Recent advances have shown that, in addition to their function in vacuolar accumulation of Na+, proteins of the NHX family are endosomal transporters that also play critical roles in K+ homeostasis, luminal pH control, and vesicle trafficking. The plasma membrane SOS1 protein from Arabidopsis thaliana, a highly specific Na+/H+ exchanger that catalyses Na+ efflux and that regulates its root/shoot distribution, has also revealed surprising interactions with K+ uptake mechanisms by roots. Finally, the function of individual members of the large CHX family remains largely unknown but two CHX isoforms, AtCHX17 and AtCH23, have been shown to affect K+ homeostasis and the control of chloroplast pH, respectively. Recent advances on the understanding of the physiological processes that are governed by these three families of cation exchangers are reviewed and discussed.
Key words: Endosomes, intracellular localization, ion exchangers, membrane transport, mineral nutrition, pH regulation, potassium, salinity, sodium, vacuole, vesicle trafficking
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
G. Batelli, P. E. Verslues, F. Agius, Q. Qiu, H. Fujii, S. Pan, K. S. Schumaker, S. Grillo, and J.-K. Zhu SOS2 Promotes Salt Tolerance in Part by Interacting with the Vacuolar H+-ATPase and Upregulating Its Transport Activity Mol. Cell. Biol., November 15, 2007; 27(22): 7781 - 7790. [Abstract] [Full Text] [PDF] |
||||
![]() |
S.-M. Wang, J.-L. Zhang, and T. J. Flowers Low-Affinity Na+ Uptake in the Halophyte Suaeda maritima Plant Physiology, October 1, 2007; 145(2): 559 - 571. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Barrero-Gil, A. Rodriguez-Navarro, and B. Benito Cloning of the PpNHAD1 transporter of Physcomitrella patens, a chloroplast transporter highly conserved in photosynthetic eukaryotic organisms J. Exp. Bot., August 1, 2007; 58(11): 2839 - 2849. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Lunde, D. P. Drew, A. K. Jacobs, and M. Tester Exclusion of Na+ via Sodium ATPase (PpENA1) Ensures Normal Growth of Physcomitrella patens under Moderate Salt Stress Plant Physiology, August 1, 2007; 144(4): 1786 - 1796. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Hanana, O. Cagnac, T. Yamaguchi, S. Hamdi, A. Ghorbel, and E. Blumwald A Grape Berry (Vitis vinifera L.) Cation/Proton Antiporter is Associated with Berry Ripening Plant Cell Physiol., June 1, 2007; 48(6): 804 - 811. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Padmanaban, S. Chanroj, J. M. Kwak, X. Li, J. M. Ward, and H. Sze Participation of Endomembrane Cation/H+ Exchanger AtCHX20 in Osmoregulation of Guard Cells Plant Physiology, May 1, 2007; 144(1): 82 - 93. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Martinez-Atienza, X. Jiang, B. Garciadeblas, I. Mendoza, J.-K. Zhu, J. M. Pardo, and F. J. Quintero Conservation of the Salt Overly Sensitive Pathway in Rice Plant Physiology, February 1, 2007; 143(2): 1001 - 1012. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. W. Szczerba, D. T. Britto, and H. J. Kronzucker Rapid, Futile K+ Cycling and Pool-Size Dynamics Define Low-Affinity Potassium Transport in Barley Plant Physiology, August 1, 2006; 141(4): 1494 - 1507. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Maggio, J.-K. Zhu, P. M. Hasegawa, and R. A. Bressan Osmogenetics: Aristotle to Arabidopsis PLANT CELL, July 1, 2006; 18(7): 1542 - 1557. [Full Text] [PDF] |
||||




