Mapping of HKT1;5 gene in barley using gwas approach and its implication in salt tolerance mechanism

Khaled M. Hazzouri, Basel Khraiwesh, Khaled M.A. Amiri, Duke Pauli, Tom Blake, Mohammad Shahid, Sangeeta K. Mullath, David Nelson, Alain L. Mansour, Kourosh Salehi-Ashtiani, Michael Purugganan, Khaled Masmoudi

Research output: Contribution to journalArticle

Abstract

Sodium (Na+) accumulation in the cytosol will result in ion homeostasis imbalance and toxicity of transpiring leaves. Studies of salinity tolerance in the diploid wheat ancestor Triticum monococcum showed that HKT1;5-like gene was a major gene in the QTL for salt tolerance, named Nax2. In the present study, we were interested in investigating the molecular mechanisms underpinning the role of the HKT1;5 gene in salt tolerance in barley (Hordeum vulgare). A USDA mini-core collection of 2,671 barley lines, part of a field trial was screened for salinity tolerance, and a Genome Wide Association Study (GWAS) was performed. Our results showed important SNPs that are correlated with salt tolerance that mapped to a region where HKT1;5 ion transporter locatedon chromosome four. Furthermore, sodium (Na+) and potassium (K+) content analysis revealed that tolerant lines accumulate more sodium in roots and leaf sheaths, than in the sensitive ones. In contrast, sodium concentration was reduced in leaf blades of the tolerant lines under salt stress. In the absence of NaCl, the concentration of Na+ andK+ were the same in the roots, leaf sheaths and leaf blades between the tolerant and the sensitive lines. In order to study the molecular mechanismbehind that, alleles of the HKT1;5 gene fromfive tolerant and five sensitive barley lines were cloned and sequenced. Sequence analysis did not show the presence of any polymorphism that distinguishes between the tolerant and sensitive alleles. Our real-time RT-PCR experiments, showed that the expression of HKT1;5 gene in roots of the tolerant line was significantly induced after challenging the plants with salt stress. In contrast, in leaf sheaths the expression was decreased after salt treatment. In sensitive lines, there was no difference in the expression of HKT1;5 gene in leaf sheath under control and saline conditions, while a slight increase in the expression was observed in roots after salt treatment. These results provide stronger evidence that HKT1;5 gene in barley play a key role in withdrawing Na+ from the xylem and therefore reducing its transport to leaves. Given all that, these data support the hypothesis that HKT1;5 gene is responsible for Na+ unloading to the xylemand controlling its distribution in the shoots, which provide new insight into the understanding of this QTL for salinity tolerance in barley.

Original languageEnglish (US)
Article number156
JournalFrontiers in Plant Science
Volume9
DOIs
StatePublished - Feb 19 2018

Fingerprint

salt tolerance
barley
sodium
genes
leaves
salinity
leaf blade
salt stress
quantitative trait loci
ions
salts
alleles
Triticum monococcum
major genes
cytosol
USDA
Hordeum vulgare
xylem
transporters
homeostasis

Keywords

  • 5 gene
  • Barley
  • GWAS
  • HKT1
  • Salinity tolerance
  • Sodium transport

ASJC Scopus subject areas

  • Plant Science

Cite this

Hazzouri, K. M., Khraiwesh, B., Amiri, K. M. A., Pauli, D., Blake, T., Shahid, M., ... Masmoudi, K. (2018). Mapping of HKT1;5 gene in barley using gwas approach and its implication in salt tolerance mechanism. Frontiers in Plant Science, 9, [156]. https://doi.org/10.3389/fpls.2018.00156

Mapping of HKT1;5 gene in barley using gwas approach and its implication in salt tolerance mechanism. / Hazzouri, Khaled M.; Khraiwesh, Basel; Amiri, Khaled M.A.; Pauli, Duke; Blake, Tom; Shahid, Mohammad; Mullath, Sangeeta K.; Nelson, David; Mansour, Alain L.; Salehi-Ashtiani, Kourosh; Purugganan, Michael; Masmoudi, Khaled.

In: Frontiers in Plant Science, Vol. 9, 156, 19.02.2018.

Research output: Contribution to journalArticle

Hazzouri, Khaled M. ; Khraiwesh, Basel ; Amiri, Khaled M.A. ; Pauli, Duke ; Blake, Tom ; Shahid, Mohammad ; Mullath, Sangeeta K. ; Nelson, David ; Mansour, Alain L. ; Salehi-Ashtiani, Kourosh ; Purugganan, Michael ; Masmoudi, Khaled. / Mapping of HKT1;5 gene in barley using gwas approach and its implication in salt tolerance mechanism. In: Frontiers in Plant Science. 2018 ; Vol. 9.
@article{210bc486892b4876aabe165a5951cdd8,
title = "Mapping of HKT1;5 gene in barley using gwas approach and its implication in salt tolerance mechanism",
abstract = "Sodium (Na+) accumulation in the cytosol will result in ion homeostasis imbalance and toxicity of transpiring leaves. Studies of salinity tolerance in the diploid wheat ancestor Triticum monococcum showed that HKT1;5-like gene was a major gene in the QTL for salt tolerance, named Nax2. In the present study, we were interested in investigating the molecular mechanisms underpinning the role of the HKT1;5 gene in salt tolerance in barley (Hordeum vulgare). A USDA mini-core collection of 2,671 barley lines, part of a field trial was screened for salinity tolerance, and a Genome Wide Association Study (GWAS) was performed. Our results showed important SNPs that are correlated with salt tolerance that mapped to a region where HKT1;5 ion transporter locatedon chromosome four. Furthermore, sodium (Na+) and potassium (K+) content analysis revealed that tolerant lines accumulate more sodium in roots and leaf sheaths, than in the sensitive ones. In contrast, sodium concentration was reduced in leaf blades of the tolerant lines under salt stress. In the absence of NaCl, the concentration of Na+ andK+ were the same in the roots, leaf sheaths and leaf blades between the tolerant and the sensitive lines. In order to study the molecular mechanismbehind that, alleles of the HKT1;5 gene fromfive tolerant and five sensitive barley lines were cloned and sequenced. Sequence analysis did not show the presence of any polymorphism that distinguishes between the tolerant and sensitive alleles. Our real-time RT-PCR experiments, showed that the expression of HKT1;5 gene in roots of the tolerant line was significantly induced after challenging the plants with salt stress. In contrast, in leaf sheaths the expression was decreased after salt treatment. In sensitive lines, there was no difference in the expression of HKT1;5 gene in leaf sheath under control and saline conditions, while a slight increase in the expression was observed in roots after salt treatment. These results provide stronger evidence that HKT1;5 gene in barley play a key role in withdrawing Na+ from the xylem and therefore reducing its transport to leaves. Given all that, these data support the hypothesis that HKT1;5 gene is responsible for Na+ unloading to the xylemand controlling its distribution in the shoots, which provide new insight into the understanding of this QTL for salinity tolerance in barley.",
keywords = "5 gene, Barley, GWAS, HKT1, Salinity tolerance, Sodium transport",
author = "Hazzouri, {Khaled M.} and Basel Khraiwesh and Amiri, {Khaled M.A.} and Duke Pauli and Tom Blake and Mohammad Shahid and Mullath, {Sangeeta K.} and David Nelson and Mansour, {Alain L.} and Kourosh Salehi-Ashtiani and Michael Purugganan and Khaled Masmoudi",
year = "2018",
month = "2",
day = "19",
doi = "10.3389/fpls.2018.00156",
language = "English (US)",
volume = "9",
journal = "Frontiers in Plant Science",
issn = "1664-462X",
publisher = "Frontiers Media S. A.",

}

TY - JOUR

T1 - Mapping of HKT1;5 gene in barley using gwas approach and its implication in salt tolerance mechanism

AU - Hazzouri, Khaled M.

AU - Khraiwesh, Basel

AU - Amiri, Khaled M.A.

AU - Pauli, Duke

AU - Blake, Tom

AU - Shahid, Mohammad

AU - Mullath, Sangeeta K.

AU - Nelson, David

AU - Mansour, Alain L.

AU - Salehi-Ashtiani, Kourosh

AU - Purugganan, Michael

AU - Masmoudi, Khaled

PY - 2018/2/19

Y1 - 2018/2/19

N2 - Sodium (Na+) accumulation in the cytosol will result in ion homeostasis imbalance and toxicity of transpiring leaves. Studies of salinity tolerance in the diploid wheat ancestor Triticum monococcum showed that HKT1;5-like gene was a major gene in the QTL for salt tolerance, named Nax2. In the present study, we were interested in investigating the molecular mechanisms underpinning the role of the HKT1;5 gene in salt tolerance in barley (Hordeum vulgare). A USDA mini-core collection of 2,671 barley lines, part of a field trial was screened for salinity tolerance, and a Genome Wide Association Study (GWAS) was performed. Our results showed important SNPs that are correlated with salt tolerance that mapped to a region where HKT1;5 ion transporter locatedon chromosome four. Furthermore, sodium (Na+) and potassium (K+) content analysis revealed that tolerant lines accumulate more sodium in roots and leaf sheaths, than in the sensitive ones. In contrast, sodium concentration was reduced in leaf blades of the tolerant lines under salt stress. In the absence of NaCl, the concentration of Na+ andK+ were the same in the roots, leaf sheaths and leaf blades between the tolerant and the sensitive lines. In order to study the molecular mechanismbehind that, alleles of the HKT1;5 gene fromfive tolerant and five sensitive barley lines were cloned and sequenced. Sequence analysis did not show the presence of any polymorphism that distinguishes between the tolerant and sensitive alleles. Our real-time RT-PCR experiments, showed that the expression of HKT1;5 gene in roots of the tolerant line was significantly induced after challenging the plants with salt stress. In contrast, in leaf sheaths the expression was decreased after salt treatment. In sensitive lines, there was no difference in the expression of HKT1;5 gene in leaf sheath under control and saline conditions, while a slight increase in the expression was observed in roots after salt treatment. These results provide stronger evidence that HKT1;5 gene in barley play a key role in withdrawing Na+ from the xylem and therefore reducing its transport to leaves. Given all that, these data support the hypothesis that HKT1;5 gene is responsible for Na+ unloading to the xylemand controlling its distribution in the shoots, which provide new insight into the understanding of this QTL for salinity tolerance in barley.

AB - Sodium (Na+) accumulation in the cytosol will result in ion homeostasis imbalance and toxicity of transpiring leaves. Studies of salinity tolerance in the diploid wheat ancestor Triticum monococcum showed that HKT1;5-like gene was a major gene in the QTL for salt tolerance, named Nax2. In the present study, we were interested in investigating the molecular mechanisms underpinning the role of the HKT1;5 gene in salt tolerance in barley (Hordeum vulgare). A USDA mini-core collection of 2,671 barley lines, part of a field trial was screened for salinity tolerance, and a Genome Wide Association Study (GWAS) was performed. Our results showed important SNPs that are correlated with salt tolerance that mapped to a region where HKT1;5 ion transporter locatedon chromosome four. Furthermore, sodium (Na+) and potassium (K+) content analysis revealed that tolerant lines accumulate more sodium in roots and leaf sheaths, than in the sensitive ones. In contrast, sodium concentration was reduced in leaf blades of the tolerant lines under salt stress. In the absence of NaCl, the concentration of Na+ andK+ were the same in the roots, leaf sheaths and leaf blades between the tolerant and the sensitive lines. In order to study the molecular mechanismbehind that, alleles of the HKT1;5 gene fromfive tolerant and five sensitive barley lines were cloned and sequenced. Sequence analysis did not show the presence of any polymorphism that distinguishes between the tolerant and sensitive alleles. Our real-time RT-PCR experiments, showed that the expression of HKT1;5 gene in roots of the tolerant line was significantly induced after challenging the plants with salt stress. In contrast, in leaf sheaths the expression was decreased after salt treatment. In sensitive lines, there was no difference in the expression of HKT1;5 gene in leaf sheath under control and saline conditions, while a slight increase in the expression was observed in roots after salt treatment. These results provide stronger evidence that HKT1;5 gene in barley play a key role in withdrawing Na+ from the xylem and therefore reducing its transport to leaves. Given all that, these data support the hypothesis that HKT1;5 gene is responsible for Na+ unloading to the xylemand controlling its distribution in the shoots, which provide new insight into the understanding of this QTL for salinity tolerance in barley.

KW - 5 gene

KW - Barley

KW - GWAS

KW - HKT1

KW - Salinity tolerance

KW - Sodium transport

UR - http://www.scopus.com/inward/record.url?scp=85043386289&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85043386289&partnerID=8YFLogxK

U2 - 10.3389/fpls.2018.00156

DO - 10.3389/fpls.2018.00156

M3 - Article

AN - SCOPUS:85043386289

VL - 9

JO - Frontiers in Plant Science

JF - Frontiers in Plant Science

SN - 1664-462X

M1 - 156

ER -