title: Rice Stomatal Closure Requires Guard Cell Plasma Membrane ATP-Binding Cassette Transporter RCN1/OsABCG5.
abstract: Water stress is one of the major environmental stresses that affect agricultural production worldwide. Water loss from plants occurs primarily through stomatal pores. Here, we report that an Oryza sativa half-size ATP-binding cassette (ABC) subfamily G protein, RCN1/OsABCG5, is involved in stomatal closure mediated by phytohormone abscisic acid (ABA) accumulation in guard cells. We found that the GFP-RCN1/OsABCG5-fusion protein was localized at the plasma membrane in guard cells. The percentage of guard cell pairs containing both ABA and GFP-RCN1/OsABCG5 increased after exogenous ABA treatment, whereas they were co-localized in guard cell pairs regardless of whether exogenous ABA was applied. ABA application resulted in a smaller increase in the percentage of guard cell pairs containing ABA in rcn1 mutant (A684P) and RCN1-RNAi than in wild-type plants. Furthermore, polyethylene glycol (drought stress)-inducible ABA accumulation in guard cells did not occur in rcn1 mutants. Stomata closure mediated by exogenous ABA application was strongly reduced in rcn1 mutants. Finally, rcn1 mutant plants had more rapid water loss from detached leaves than the wild-type plants. These results indicate that in response to drought stress, RCN1/OsABCG5 is involved in accumulation of ABA in guard cells, which is indispensable for stomatal closure.
authors.affiliation: Department of Agro-environmental Science, Obihiro University of Agricultural and Veterinary Medicine, 2-11 Nishi, Inada, Obihiro, Hokkaido 080-0834, Japan. Electronic address: matsudas@obihiro.ac.jp.
authors.forename: Shuichi
authors.initials: S
authors.lastname: Matsuda
authors.affiliation: Department of Agro-environmental Science, Obihiro University of Agricultural and Veterinary Medicine, 2-11 Nishi, Inada, Obihiro, Hokkaido 080-0834, Japan.
authors.forename: Sho
authors.initials: S
authors.lastname: Takano
authors.affiliation: Department of Agro-environmental Science, Obihiro University of Agricultural and Veterinary Medicine, 2-11 Nishi, Inada, Obihiro, Hokkaido 080-0834, Japan.
authors.forename: Moeko
authors.initials: M
authors.lastname: Sato
authors.affiliation: Department of Agro-environmental Science, Obihiro University of Agricultural and Veterinary Medicine, 2-11 Nishi, Inada, Obihiro, Hokkaido 080-0834, Japan.
authors.forename: Kaoru
authors.initials: K
authors.lastname: Furukawa
authors.affiliation: Department of Agro-environmental Science, Obihiro University of Agricultural and Veterinary Medicine, 2-11 Nishi, Inada, Obihiro, Hokkaido 080-0834, Japan.
authors.forename: Hidetaka
authors.initials: H
authors.lastname: Nagasawa
authors.affiliation: Department of Agro-environmental Science, Obihiro University of Agricultural and Veterinary Medicine, 2-11 Nishi, Inada, Obihiro, Hokkaido 080-0834, Japan.
authors.forename: Shoko
authors.initials: S
authors.lastname: Yoshikawa
authors.affiliation: Department of Agro-environmental Science, Obihiro University of Agricultural and Veterinary Medicine, 2-11 Nishi, Inada, Obihiro, Hokkaido 080-0834, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Kasuga
authors.affiliation: Department of Food Science, Obihiro University of Agricultural and Veterinary Medicine, 2-11 Nishi, Inada, Obihiro, Hokkaido 080-0834, Japan.
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Tokuji
authors.affiliation: Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan.
authors.forename: Kazufumi
authors.initials: K
authors.lastname: Yazaki
authors.affiliation: Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa, Nagoya, Aichi 464-8601, Japan.
authors.forename: Mikio
authors.initials: M
authors.lastname: Nakazono
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 Agricultural and Veterinary Medicine, 2-11 Nishi, Inada, Obihiro, Hokkaido 080-0834, Japan. Electronic address: kiyoaki@obihiro.ac.jp.
authors.forename: Kiyoaki
authors.initials: K
authors.lastname: Kato
mesh_terms: D000071018:ATP Binding Cassette Transporter, Subfamily G, Member 5 / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism*; D055864:Droughts; D009154:Mutation; D012275:Oryza / Q000033:anatomy & histology / Q000166:cytology* / Q000378:metabolism* / Q000502:physiology; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D054046:Plant Stomata / Q000033:anatomy & histology*; D055503:Protein Multimerization; D020836:Protein Structure, Quaternary; D021381:Protein Transport; D013312:Stress, Physiological; D015854:Up-Regulation
chemical_list: D000071018:ATP Binding Cassette Transporter, Subfamily G, Member 5; D010940:Plant Proteins
keywords: ABC transporter; abscisic acid; drought stress; rice; stomatal closure