title: A rice quantitative trait locus for salt tolerance encodes a sodium transporter.
abstract: Many important agronomic traits in crop plants, including stress tolerance, are complex traits controlled by quantitative trait loci (QTLs). Isolation of these QTLs holds great promise to improve world agriculture but is a challenging task. We previously mapped a rice QTL, SKC1, that maintained K(+) homeostasis in the salt-tolerant variety under salt stress, consistent with the earlier finding that K(+) homeostasis is important in salt tolerance. To understand the molecular basis of this QTL, we isolated the SKC1 gene by map-based cloning and found that it encoded a member of HKT-type transporters. SKC1 is preferentially expressed in the parenchyma cells surrounding the xylem vessels. Voltage-clamp analysis showed that SKC1 protein functions as a Na(+)-selective transporter. Physiological analysis suggested that SKC1 is involved in regulating K(+)/Na(+) homeostasis under salt stress, providing a potential tool for improving salt tolerance in crops.
authors.affiliation: National Key Laboratory of Plant Molecular Genetics, Shanghai Institute of Plant Physiology and Ecology, Shanghai Institute for Biological Sciences, The Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China.
authors.forename: Zhong-Hai
authors.initials: ZH
authors.lastname: Ren
authors.forename: Ji-Ping
authors.initials: JP
authors.lastname: Gao
authors.forename: Le-Gong
authors.initials: LG
authors.lastname: Li
authors.forename: Xiu-Ling
authors.initials: XL
authors.lastname: Cai
authors.forename: Wei
authors.initials: W
authors.lastname: Huang
authors.forename: Dai-Yin
authors.initials: DY
authors.lastname: Chao
authors.forename: Mei-Zhen
authors.initials: MZ
authors.lastname: Zhu
authors.forename: Zong-Yang
authors.initials: ZY
authors.lastname: Wang
authors.forename: Sheng
authors.initials: S
authors.lastname: Luan
authors.forename: Hong-Xuan
authors.initials: HX
authors.lastname: Lin
mesh_terms: D001483:Base Sequence; D003001:Cloning, Molecular; D005816:Genetic Complementation Test; D017136:Ion Transport / Q000235:genetics; D008969:Molecular Sequence Data; D012275:Oryza / Q000235:genetics / Q000378:metabolism*; D011188:Potassium / Q000032:analysis; D015221:Potassium Channels / Q000235:genetics / Q000502:physiology; D040641:Quantitative Trait Loci; D012492:Salts / Q000378:metabolism; D012964:Sodium / Q000032:analysis / Q000378:metabolism*; D015222:Sodium Channels / Q000235:genetics* / Q000502:physiology*; D012965:Sodium Chloride / Q000378:metabolism
chemical_list: D015221:Potassium Channels; D012492:Salts; D015222:Sodium Channels; D012965:Sodium Chloride; D012964:Sodium; D011188:Potassium