title: SKP1 is involved in abscisic acid signalling to regulate seed germination, stomatal opening and root growth in Arabidopsis thaliana.
abstract: Abscisic acid (ABA) regulates many aspects of plant development, including seed dormancy and germination, root growth and stomatal closure. Plant SKP1 proteins are subunits of the SCF complex E3 ligases, which regulate several phytohormone signalling pathways through protein degradation. However, little is known about SKP1 proteins participating in ABA signalling. Here, we report that the overexpression of Triticum aestivum SKP1-like 1 (TSK1) in Arabidopsis thaliana (Arabidopsis) resulted in delayed seed germination and hypersensitivity to ABA. The opening of stomatal guard cells and the transcription of several ABA-responsive genes were affected in transgenic plants. In contrast, Arabidopsis skp1-like 1 (ask1)/ask1 ASK2/ask2 seedlings exhibited reduced ABA sensitivity. Furthermore, the transcription of ASK1 and ASK2 was down-regulated in abi1-1 and abi5-1 mutants compared with that in wild type. ASK1 or ASK2 overexpression could rescue or partially rescue the ABA insensitivity of abi5-1 mutants, respectively. Our work demonstrates that SKP1 is involved in ABA signalling and that SKP1-like genes may positively regulate ABA signalling by SCF-mediated protein degradation.
authors.affiliation: Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Chijun
authors.initials: C
authors.lastname: Li
authors.forename: Zuojun
authors.initials: Z
authors.lastname: Liu
authors.forename: Qirui
authors.initials: Q
authors.lastname: Zhang
authors.forename: Ruozhong
authors.initials: R
authors.lastname: Wang
authors.forename: Langtao
authors.initials: L
authors.lastname: Xiao
authors.forename: Hong
authors.initials: H
authors.lastname: Ma
authors.forename: Kang
authors.initials: K
authors.lastname: Chong
authors.forename: Yunyuan
authors.initials: Y
authors.lastname: Xu
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism*; D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics; D015536:Down-Regulation / Q000235:genetics; D018507:Gene Expression Regulation, Developmental / Q000235:genetics; D018506:Gene Expression Regulation, Plant / Q000235:genetics; D018525:Germination; D009154:Mutation; D010937:Plant Growth Regulators / Q000378:metabolism*; D018515:Plant Leaves / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D010940:Plant Proteins / Q000235:genetics / Q000502:physiology; D018517:Plant Roots / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D054046:Plant Stomata / Q000378:metabolism; D030821:Plants, Genetically Modified; D059748:Proteolysis; D044786:S-Phase Kinase-Associated Proteins / Q000235:genetics* / Q000502:physiology; D044843:SKP Cullin F-Box Protein Ligases / Q000235:genetics; D036226:Seedlings / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D015398:Signal Transduction / Q000235:genetics*; D014908:Triticum / Q000235:genetics
chemical_list: C120363:ASK1 protein, Arabidopsis; D029681:Arabidopsis Proteins; D010937:Plant Growth Regulators; D010940:Plant Proteins; D044786:S-Phase Kinase-Associated Proteins; D000040:Abscisic Acid; C484058:ASK2 protein, Arabidopsis; D044843:SKP Cullin F-Box Protein Ligases