title: Rice RCN1/OsABCG5 mutation alters accumulation of essential and nonessential minerals and causes a high Na/K ratio, resulting in a salt-sensitive phenotype.
abstract: Mineral balance and salt stress are major factors affecting plant growth and yield. Here, we characterized the effects of rice (Oryza sativa L.) reduced culm number1 (rcn1), encoding a G subfamily ABC transporter (OsABCG5) involved in accumulation of essential and nonessential minerals, the Na/K ratio, and salt tolerance. Reduced potassium and elevated sodium in field-grown plants were evident in rcn1 compared to original line 'Shiokari' and four independent rcn mutants, rcn2, rcn4, rcn5 and rcn6. A high Na/K ratio was evident in the shoots and roots of rcn1 under K starvation and salt stress in hydroponically cultured plants. Downregulation of SKC1/OsHKT1;5 in rcn1 shoots under salt stress demonstrated that normal function of RCN1/OsABCG5 is essential for upregulation of SKC1/OsHKT1;5 under salt stress. The accumulation of various minerals in shoots and roots was also altered in the rcn1 mutant compared to 'Shiokari' under control conditions, potassium starvation, and salt and d-sorbitol treatments. The rcn1 mutation resulted in a salt-sensitive phenotype. We concluded that RCN1/OsABCG5 is a salt tolerance factor that acts via Na/K homeostasis, at least partly by regulation of SKC1/OsHKT1;5 in shoots.
authors.affiliation: Department of Agro-Environmental Science, Obihiro University of Agriculture and Veterinary Medicine, Nishi 2-11 Inada, Obihiro, Hokkaido 080-8555, Japan.
authors.forename: Shuichi
authors.initials: S
authors.lastname: Matsuda
authors.affiliation: Department of Agro-Environmental Science, Obihiro University of Agriculture and Veterinary Medicine, Nishi 2-11 Inada, Obihiro, Hokkaido 080-8555, Japan.
authors.forename: Hidetaka
authors.initials: H
authors.lastname: Nagasawa
authors.affiliation: Department of Agro-Environmental Science, Obihiro University of Agriculture and Veterinary Medicine, Nishi 2-11 Inada, Obihiro, Hokkaido 080-8555, Japan.
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Yamashiro
authors.affiliation: Department of Agro-Environmental Science, Obihiro University of Agriculture and Veterinary Medicine, Nishi 2-11 Inada, Obihiro, Hokkaido 080-8555, Japan.
authors.forename: Naoko
authors.initials: N
authors.lastname: Yasuno
authors.affiliation: Graduate School of Agriculture, Hokkaido University, Kita 9 Nishi 9, Kita-ku, Sapporo, Hokkaido 060-8589, Japan.
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Watanabe
authors.affiliation: Department of Agro-Environmental Science, Obihiro University of Agriculture and Veterinary Medicine, Nishi 2-11 Inada, Obihiro, Hokkaido 080-8555, Japan.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Kitazawa
authors.affiliation: Department of Agro-Environmental Science, Obihiro University of Agriculture and Veterinary Medicine, Nishi 2-11 Inada, Obihiro, Hokkaido 080-8555, Japan.
authors.forename: Sho
authors.initials: S
authors.lastname: Takano
authors.affiliation: Department of Food Science, Obihiro University of Agriculture and Veterinary Medicine, Nishi 2-11 Inada, Obihiro, Hokkaido 080-8555, Japan.
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Tokuji
authors.affiliation: Department of Food Science, Obihiro University of Agriculture and Veterinary Medicine, Nishi 2-11 Inada, Obihiro, Hokkaido 080-8555, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Tani
authors.affiliation: Graduate School of Agriculture, Hokkaido University, Kita 9 Nishi 9, Kita-ku, Sapporo, Hokkaido 060-8589, Japan.
authors.forename: Itsuro
authors.initials: I
authors.lastname: Takamure
authors.affiliation: Department of Agro-Environmental Science, Obihiro University of Agriculture and Veterinary Medicine, Nishi 2-11 Inada, Obihiro, Hokkaido 080-8555, Japan. Electronic address: kiyoaki@obihiro.ac.jp.
authors.forename: Kiyoaki
authors.initials: K
authors.lastname: Kato
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics* / Q000378:metabolism; D000222:Adaptation, Physiological / Q000235:genetics*; D027682:Cation Transport Proteins; D015870:Gene Expression; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D006706:Homeostasis; D008903:Minerals / Q000378:metabolism*; D009154:Mutation; D012275:Oryza / Q000235:genetics* / Q000378:metabolism; D010641:Phenotype; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000378:metabolism; D018520:Plant Shoots / Q000378:metabolism; D011188:Potassium / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism*; D012965:Sodium Chloride / Q000378:metabolism; D013312:Stress, Physiological / Q000235:genetics; D027981:Symporters
chemical_list: D018528:ATP-Binding Cassette Transporters; D027682:Cation Transport Proteins; C088864:HKT1 protein, plant; D008903:Minerals; D010940:Plant Proteins; D027981:Symporters; D012965:Sodium Chloride; D012964:Sodium; D011188:Potassium
keywords: ABC transporter; Mineral balance; Na/K ratio; SKC1/OsHKT1 ;5; Salt tolerance