The role of Na+ and K+ transporters in salt stress adaptation in glycophytes

Dekoum V.M. Assaha, Akihiro Ueda, Hirofumi Saneoka, Rashid Al-Yahyai, Mahmoud W. Yaish

Research output: Contribution to journalReview article

62 Citations (Scopus)

Abstract

Ionic stress is one of the most important components of salinity and is brought about by excess Na+ accumulation, especially in the aerial parts of plants. Since Na+ interferes with K+ homeostasis, and especially given its involvement in numerous metabolic processes, maintaining a balanced cytosolic Na+/K+ ratio has become a key salinity tolerance mechanism. Achieving this homeostatic balance requires the activity of Na+ and K+ transporters and/or channels. The mechanism of Na+ and K+ uptake and translocation in glycophytes and halophytes is essentially the same, but glycophytes are more susceptible to ionic stress than halophytes. The transport mechanisms involve Na+ and/or K+ transporters and channels as well as non-selective cation channels. Thus, the question arises of whether the difference in salt tolerance between glycophytes and halophytes could be the result of differences in the proteins or in the expression of genes coding the transporters. The aim of this review is to seek answers to this question by examining the role of major Na+ and K+ transporters and channels in Na+ and K+ uptake, translocation and intracellular homeostasis in glycophytes. It turns out that these transporters and channels are equally important for the adaptation of glycophytes as they are for halophytes, but differential gene expression, structural differences in the proteins (single nucleotide substitutions, impacting affinity) and post-translational modifications (phosphorylation) account for the differences in their activity and hence the differences in tolerance between the two groups. Furthermore, lack of the ability to maintain stable plasma membrane (PM) potentials following Na+-induced depolarization is also crucial for salt stress tolerance. This stable membrane potential is sustained by the activity of Na+/H+ antiporters such as SOS1 at the PM. Moreover, novel regulators of Na+ and K+ transport pathways including the Nax1 and Nax2 loci regulation of SOS1 expression and activity in the stele, and haem oxygenase involvement in stabilizing membrane potential by activating H+-ATPase activity, favorable for K+ uptake through HAK/AKT1, have been shown and are discussed.

Original languageEnglish
Article number509
JournalFrontiers in Physiology
Volume8
Issue numberJUL
DOIs
Publication statusPublished - Jul 18 2017

Fingerprint

Salt-Tolerant Plants
Salts
Membrane Potentials
Salt-Tolerance
Salinity
Homeostasis
Aerial Plant Components
Cell Membrane
Gene Expression
Heme Oxygenase (Decyclizing)
Sodium-Hydrogen Antiporter
Proton-Translocating ATPases
Post Translational Protein Processing
Cations
Proteins
Nucleotides
Phosphorylation

Keywords

  • Abiotic stress
  • Glycophytes
  • Halophytes
  • Potassium transporters
  • Salinity
  • Sodium transporters

ASJC Scopus subject areas

  • Physiology
  • Physiology (medical)

Cite this

The role of Na+ and K+ transporters in salt stress adaptation in glycophytes. / Assaha, Dekoum V.M.; Ueda, Akihiro; Saneoka, Hirofumi; Al-Yahyai, Rashid; Yaish, Mahmoud W.

In: Frontiers in Physiology, Vol. 8, No. JUL, 509, 18.07.2017.

Research output: Contribution to journalReview article

@article{0daa7c3a464b45f1ac5b318e2a8586c3,
title = "The role of Na+ and K+ transporters in salt stress adaptation in glycophytes",
abstract = "Ionic stress is one of the most important components of salinity and is brought about by excess Na+ accumulation, especially in the aerial parts of plants. Since Na+ interferes with K+ homeostasis, and especially given its involvement in numerous metabolic processes, maintaining a balanced cytosolic Na+/K+ ratio has become a key salinity tolerance mechanism. Achieving this homeostatic balance requires the activity of Na+ and K+ transporters and/or channels. The mechanism of Na+ and K+ uptake and translocation in glycophytes and halophytes is essentially the same, but glycophytes are more susceptible to ionic stress than halophytes. The transport mechanisms involve Na+ and/or K+ transporters and channels as well as non-selective cation channels. Thus, the question arises of whether the difference in salt tolerance between glycophytes and halophytes could be the result of differences in the proteins or in the expression of genes coding the transporters. The aim of this review is to seek answers to this question by examining the role of major Na+ and K+ transporters and channels in Na+ and K+ uptake, translocation and intracellular homeostasis in glycophytes. It turns out that these transporters and channels are equally important for the adaptation of glycophytes as they are for halophytes, but differential gene expression, structural differences in the proteins (single nucleotide substitutions, impacting affinity) and post-translational modifications (phosphorylation) account for the differences in their activity and hence the differences in tolerance between the two groups. Furthermore, lack of the ability to maintain stable plasma membrane (PM) potentials following Na+-induced depolarization is also crucial for salt stress tolerance. This stable membrane potential is sustained by the activity of Na+/H+ antiporters such as SOS1 at the PM. Moreover, novel regulators of Na+ and K+ transport pathways including the Nax1 and Nax2 loci regulation of SOS1 expression and activity in the stele, and haem oxygenase involvement in stabilizing membrane potential by activating H+-ATPase activity, favorable for K+ uptake through HAK/AKT1, have been shown and are discussed.",
keywords = "Abiotic stress, Glycophytes, Halophytes, Potassium transporters, Salinity, Sodium transporters",
author = "Assaha, {Dekoum V.M.} and Akihiro Ueda and Hirofumi Saneoka and Rashid Al-Yahyai and Yaish, {Mahmoud W.}",
year = "2017",
month = "7",
day = "18",
doi = "10.3389/fphys.2017.00509",
language = "English",
volume = "8",
journal = "Frontiers in Physiology",
issn = "1664-042X",
publisher = "Frontiers Research Foundation",
number = "JUL",

}

TY - JOUR

T1 - The role of Na+ and K+ transporters in salt stress adaptation in glycophytes

AU - Assaha, Dekoum V.M.

AU - Ueda, Akihiro

AU - Saneoka, Hirofumi

AU - Al-Yahyai, Rashid

AU - Yaish, Mahmoud W.

PY - 2017/7/18

Y1 - 2017/7/18

N2 - Ionic stress is one of the most important components of salinity and is brought about by excess Na+ accumulation, especially in the aerial parts of plants. Since Na+ interferes with K+ homeostasis, and especially given its involvement in numerous metabolic processes, maintaining a balanced cytosolic Na+/K+ ratio has become a key salinity tolerance mechanism. Achieving this homeostatic balance requires the activity of Na+ and K+ transporters and/or channels. The mechanism of Na+ and K+ uptake and translocation in glycophytes and halophytes is essentially the same, but glycophytes are more susceptible to ionic stress than halophytes. The transport mechanisms involve Na+ and/or K+ transporters and channels as well as non-selective cation channels. Thus, the question arises of whether the difference in salt tolerance between glycophytes and halophytes could be the result of differences in the proteins or in the expression of genes coding the transporters. The aim of this review is to seek answers to this question by examining the role of major Na+ and K+ transporters and channels in Na+ and K+ uptake, translocation and intracellular homeostasis in glycophytes. It turns out that these transporters and channels are equally important for the adaptation of glycophytes as they are for halophytes, but differential gene expression, structural differences in the proteins (single nucleotide substitutions, impacting affinity) and post-translational modifications (phosphorylation) account for the differences in their activity and hence the differences in tolerance between the two groups. Furthermore, lack of the ability to maintain stable plasma membrane (PM) potentials following Na+-induced depolarization is also crucial for salt stress tolerance. This stable membrane potential is sustained by the activity of Na+/H+ antiporters such as SOS1 at the PM. Moreover, novel regulators of Na+ and K+ transport pathways including the Nax1 and Nax2 loci regulation of SOS1 expression and activity in the stele, and haem oxygenase involvement in stabilizing membrane potential by activating H+-ATPase activity, favorable for K+ uptake through HAK/AKT1, have been shown and are discussed.

AB - Ionic stress is one of the most important components of salinity and is brought about by excess Na+ accumulation, especially in the aerial parts of plants. Since Na+ interferes with K+ homeostasis, and especially given its involvement in numerous metabolic processes, maintaining a balanced cytosolic Na+/K+ ratio has become a key salinity tolerance mechanism. Achieving this homeostatic balance requires the activity of Na+ and K+ transporters and/or channels. The mechanism of Na+ and K+ uptake and translocation in glycophytes and halophytes is essentially the same, but glycophytes are more susceptible to ionic stress than halophytes. The transport mechanisms involve Na+ and/or K+ transporters and channels as well as non-selective cation channels. Thus, the question arises of whether the difference in salt tolerance between glycophytes and halophytes could be the result of differences in the proteins or in the expression of genes coding the transporters. The aim of this review is to seek answers to this question by examining the role of major Na+ and K+ transporters and channels in Na+ and K+ uptake, translocation and intracellular homeostasis in glycophytes. It turns out that these transporters and channels are equally important for the adaptation of glycophytes as they are for halophytes, but differential gene expression, structural differences in the proteins (single nucleotide substitutions, impacting affinity) and post-translational modifications (phosphorylation) account for the differences in their activity and hence the differences in tolerance between the two groups. Furthermore, lack of the ability to maintain stable plasma membrane (PM) potentials following Na+-induced depolarization is also crucial for salt stress tolerance. This stable membrane potential is sustained by the activity of Na+/H+ antiporters such as SOS1 at the PM. Moreover, novel regulators of Na+ and K+ transport pathways including the Nax1 and Nax2 loci regulation of SOS1 expression and activity in the stele, and haem oxygenase involvement in stabilizing membrane potential by activating H+-ATPase activity, favorable for K+ uptake through HAK/AKT1, have been shown and are discussed.

KW - Abiotic stress

KW - Glycophytes

KW - Halophytes

KW - Potassium transporters

KW - Salinity

KW - Sodium transporters

UR - http://www.scopus.com/inward/record.url?scp=85025463644&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85025463644&partnerID=8YFLogxK

U2 - 10.3389/fphys.2017.00509

DO - 10.3389/fphys.2017.00509

M3 - Review article

AN - SCOPUS:85025463644

VL - 8

JO - Frontiers in Physiology

JF - Frontiers in Physiology

SN - 1664-042X

IS - JUL

M1 - 509

ER -