title: The sodium transporter encoded by the HKT1;2 gene modulates sodium/potassium homeostasis in tomato shoots under salinity.
abstract: Excessive soil salinity diminishes crop yield and quality. In a previous study in tomato, we identified two closely linked genes encoding HKT1-like transporters, HKT1;1 and HKT1;2, as candidate genes for a major quantitative trait locus (kc7.1) related to shoot Na+/K+homeostasis - a major salt tolerance trait - using two populations of recombinant inbred lines (RILs). Here, we determine the effectiveness of these genes in conferring improved salt tolerance by using two near-isogenic lines (NILs) that were homozygous for either the Solanum lycopersicum allele (NIL17) or for the Solanum cheesmaniae allele (NIL14) at both HKT1 loci; transgenic lines derived from these NILs in which each HKT1;1 and HKT1;2 had been silenced by stable transformation were also used. Silencing of ScHKT1;2 and SlHKT1;2 altered the leaf Na+/K+ratio and caused hypersensitivity to salinity in plants cultivated under transpiring conditions, whereas silencing SlHKT1;1/ScHKT1;1 had a lesser effect. These results indicate that HKT1;2 has the more significant role in Na+homeostasis and salinity tolerance in tomato.
authors.affiliation: Department of Biochemistry, Molecular and Cellular Biology of Plants, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas (CSIC), C/Prof. Albareda 1, E-18008, Granada, Spain.
authors.forename: Noelia
authors.initials: N
authors.lastname: Jaime-Pérez
authors.affiliation: Laboratory of Tissue Culture and Plant Breeding, Institute of Plant Molecular and Cellular Biology, CSIC, Polytechnic University of Valencia, Valencia, 46022, Spain.
authors.forename: Benito
authors.identifier: http://orcid.org/0000-0001-9176-701X
authors.initials: B
authors.lastname: Pineda
authors.affiliation: Laboratory of Tissue Culture and Plant Breeding, Institute of Plant Molecular and Cellular Biology, CSIC, Polytechnic University of Valencia, Valencia, 46022, Spain.
authors.forename: Begoña
authors.initials: B
authors.lastname: García-Sogo
authors.affiliation: Laboratory of Tissue Culture and Plant Breeding, Institute of Plant Molecular and Cellular Biology, CSIC, Polytechnic University of Valencia, Valencia, 46022, Spain.
authors.forename: Alejandro
authors.identifier: http://orcid.org/0000-0003-1728-5471
authors.initials: A
authors.lastname: Atares
authors.affiliation: ARC Centre of Excellence in Plant Energy Biology, School of Agriculture, Food and Wine and Waite Research Institute, Waite Research Precinct, University of Adelaide, Glen Osmond, SA 5064, Australia.
authors.forename: Asmini
authors.initials: A
authors.lastname: Athman
authors.affiliation: ARC Centre of Excellence in Plant Energy Biology, School of Agriculture, Food and Wine and Waite Research Institute, Waite Research Precinct, University of Adelaide, Glen Osmond, SA 5064, Australia.
authors.forename: Caitlin S
authors.identifier: http://orcid.org/0000-0001-8549-2873
authors.initials: CS
authors.lastname: Byrt
authors.affiliation: Department of Biochemistry, Molecular and Cellular Biology of Plants, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas (CSIC), C/Prof. Albareda 1, E-18008, Granada, Spain.
authors.forename: Raquel
authors.initials: R
authors.lastname: Olías
authors.affiliation: Plant Protection and Biotechnology Center, Instituto Valenciano de Investigaciones Agrarias (IVIA), E46113 Moncada, Valencia, Spain.
authors.forename: Maria José
authors.identifier: http://orcid.org/0000-0002-4330-160X
authors.initials: MJ
authors.lastname: Asins
authors.affiliation: ARC Centre of Excellence in Plant Energy Biology, School of Agriculture, Food and Wine and Waite Research Institute, Waite Research Precinct, University of Adelaide, Glen Osmond, SA 5064, Australia.
authors.forename: Matthew
authors.identifier: http://orcid.org/0000-0003-0666-3078
authors.initials: M
authors.lastname: Gilliham
authors.affiliation: Laboratory of Tissue Culture and Plant Breeding, Institute of Plant Molecular and Cellular Biology, CSIC, Polytechnic University of Valencia, Valencia, 46022, Spain.
authors.forename: Vicente
authors.identifier: http://orcid.org/0000-0002-0345-7300
authors.initials: V
authors.lastname: Moreno
authors.affiliation: Department of Biochemistry, Molecular and Cellular Biology of Plants, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas (CSIC), C/Prof. Albareda 1, E-18008, Granada, Spain.
authors.forename: Andrés
authors.identifier: http://orcid.org/0000-0003-3187-5443
authors.initials: A
authors.lastname: Belver
mesh_terms: D000483:Alleles; D027682:Cation Transport Proteins / Q000235:genetics* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D020868:Gene Silencing / Q000187:drug effects; D017343:Genes, Plant; D056426:Genetic Loci; D006706:Homeostasis / Q000187:drug effects / Q000235:genetics; D007178:Inbreeding; D018551:Solanum lycopersicum / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*; D010641:Phenotype; D018515:Plant Leaves / Q000187:drug effects / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D018520:Plant Shoots / Q000187:drug effects / Q000378:metabolism*; D011188:Potassium / Q000378:metabolism*; D025341:Principal Component Analysis; D034622:RNA Interference; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D054712:Salinity; D012964:Sodium / Q000378:metabolism*; D012965:Sodium Chloride / Q000494:pharmacology; D027981:Symporters / Q000235:genetics* / Q000378:metabolism
chemical_list: D027682:Cation Transport Proteins; C088864:HKT1 protein, plant; D010940:Plant Proteins; D012333:RNA, Messenger; D027981:Symporters; D012965:Sodium Chloride; D012964:Sodium; D011188:Potassium
keywords: HKT1;2; Solanum lycopersicum and Solanum cheesmaniae; post-transcriptional gene silencing