title: A coastal cline in sodium accumulation in Arabidopsis thaliana is driven by natural variation of the sodium transporter AtHKT1;1.
abstract: The genetic model plant Arabidopsis thaliana, like many plant species, experiences a range of edaphic conditions across its natural habitat. Such heterogeneity may drive local adaptation, though the molecular genetic basis remains elusive. Here, we describe a study in which we used genome-wide association mapping, genetic complementation, and gene expression studies to identify cis-regulatory expression level polymorphisms at the AtHKT1;1 locus, encoding a known sodium (Na(+)) transporter, as being a major factor controlling natural variation in leaf Na(+) accumulation capacity across the global A. thaliana population. A weak allele of AtHKT1;1 that drives elevated leaf Na(+) in this population has been previously linked to elevated salinity tolerance. Inspection of the geographical distribution of this allele revealed its significant enrichment in populations associated with the coast and saline soils in Europe. The fixation of this weak AtHKT1;1 allele in these populations is genetic evidence supporting local adaptation to these potentially saline impacted environments.
authors.affiliation: United States Department of Agriculture-Agricultural Research Service, Plant Genetics Research Unit, Donald Danforth Plant Sciences Center, St. Louis, Missouri, United States of America.
authors.forename: Ivan
authors.initials: I
authors.lastname: Baxter
authors.forename: Jessica N
authors.initials: JN
authors.lastname: Brazelton
authors.forename: Danni
authors.initials: D
authors.lastname: Yu
authors.forename: Yu S
authors.initials: YS
authors.lastname: Huang
authors.forename: Brett
authors.initials: B
authors.lastname: Lahner
authors.forename: Elena
authors.initials: E
authors.lastname: Yakubova
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Joy
authors.initials: J
authors.lastname: Bergelson
authors.forename: Justin O
authors.initials: JO
authors.lastname: Borevitz
authors.forename: Magnus
authors.initials: M
authors.lastname: Nordborg
authors.forename: Olga
authors.initials: O
authors.lastname: Vitek
authors.forename: David E
authors.initials: DE
authors.lastname: Salt
mesh_terms: D000483:Alleles; D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism*; D027682:Cation Transport Proteins / Q000235:genetics* / Q000378:metabolism*; D017753:Ecosystem; D018506:Gene Expression Regulation, Plant; D005816:Genetic Complementation Test; D014644:Genetic Variation; D018745:Genome, Plant / Q000235:genetics; D055106:Genome-Wide Association Study; D005843:Geography; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism; D012623:Seawater; D012964:Sodium / Q000378:metabolism*; D027981:Symporters / Q000235:genetics* / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D027682:Cation Transport Proteins; C490286:HKT1 protein, Arabidopsis; D027981:Symporters; D012964:Sodium