title: A rice orthologue of the ABA receptor, OsPYL/RCAR5, is a positive regulator of the ABA signal transduction pathway in seed germination and early seedling growth.
abstract: Abscisic acid (ABA) is a phytohormone that positively regulates seed dormancy and stress tolerance. PYL/RCARs were identified an intracellular ABA receptors regulating ABA-dependent gene expression in Arabidopsis thaliana. However, their function in monocot species has not been characterized yet. Herein, it is demonstrated that PYL/RCAR orthologues in Oryza sativa function as a positive regulator of the ABA signal transduction pathway. Transgenic rice plants expressing OsPYL/RCAR5, a PYL/RCAR orthologue of rice, were found to be hypersensitive to ABA during seed germination and early seedling growth. A rice ABA signalling unit composed of OsPYL/RCAR5, OsPP2C30, SAPK2, and OREB1 for ABA-dependent gene regulation was further identified, via interaction assays and a transient gene expression assay. Thus, a core signalling unit for ABA-responsive gene expression modulating seed germination and early seedling growth in rice has been unravelled. This study provides substantial contributions toward understanding the ABA signal transduction pathway in rice.
authors.affiliation: Department of Bio-crop development, National Academy of Agricultural Science, Rural Development Administration, Suwon, 441-707, Korea.
authors.forename: Hyunmi
authors.initials: H
authors.lastname: Kim
authors.forename: Hyunsik
authors.initials: H
authors.lastname: Hwang
authors.forename: Jung-Woo
authors.initials: JW
authors.lastname: Hong
authors.forename: Young-Na
authors.initials: YN
authors.lastname: Lee
authors.forename: Il Pyung
authors.initials: IP
authors.lastname: Ahn
authors.forename: In Sun
authors.initials: IS
authors.lastname: Yoon
authors.forename: Sang-Dong
authors.initials: SD
authors.lastname: Yoo
authors.forename: Sukchan
authors.initials: S
authors.lastname: Lee
authors.forename: Sung Chul
authors.initials: SC
authors.lastname: Lee
authors.forename: Beom-Gi
authors.initials: BG
authors.lastname: Kim
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism* / Q000494:pharmacology; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000502:physiology; D018525:Germination / Q000502:physiology*; D008954:Models, Biological; D012275:Oryza / Q000235:genetics / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D010641:Phenotype; D057445:Plant Dormancy / Q000502:physiology; D010937:Plant Growth Regulators / Q000378:metabolism* / Q000494:pharmacology; D018515:Plant Leaves / Q000235:genetics / Q000254:growth & development / Q000378:metabolism / Q000502:physiology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified; D011523:Protoplasts; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D036226:Seedlings / Q000235:genetics / Q000254:growth & development / Q000378:metabolism / Q000502:physiology; D012639:Seeds / Q000235:genetics / Q000254:growth & development / Q000378:metabolism / Q000502:physiology; D015398:Signal Transduction / Q000502:physiology*; D014026:Nicotiana / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D020798:Two-Hybrid System Techniques
chemical_list: D010937:Plant Growth Regulators; D010940:Plant Proteins; D000040:Abscisic Acid