title: Phytochrome B and REVEILLE1/2-mediated signalling controls seed dormancy and germination in Arabidopsis.
abstract: Seeds maintain a dormant state to withstand adverse conditions and germinate when conditions become favourable to give rise to a new generation of flowering plants. Seed dormancy and germination are tightly controlled by internal and external signals. Although phytochrome photoreceptors are proposed to regulate primary seed dormancy, the underlying molecular mechanism remains elusive. Here we show that the REVEILLE1 (RVE1) and RVE2 transcription factors promote primary seed dormancy and repress red/far-red-light-reversible germination downstream of phytochrome B (phyB) in Arabidopsis thaliana. RVE1 and RVE2 expression is downregulated after imbibition and by phyB. RVE1 directly binds to the promoter of GIBBERELLIN 3-OXIDASE 2, inhibits its transcription and thus suppresses the biosynthesis of bioactive gibberellins. In addition, DELAY OF GERMINATION 1 also acts downstream of phyB. This study identifies a signalling pathway that integrates environmental light input with internal factors to control both seed dormancy and germination.
authors: Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Nanxincun 20, Xiangshan, Beijing 100093, China.|University of the Chinese Academy of Sciences, Beijing 100049, China.
authors: Zhimin
authors: Z
authors: Jiang
authors: Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Nanxincun 20, Xiangshan, Beijing 100093, China.|University of the Chinese Academy of Sciences, Beijing 100049, China.
authors: Gang
authors: G
authors: Xu
authors: Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Nanxincun 20, Xiangshan, Beijing 100093, China.
authors: Yanjun
authors: Y
authors: Jing
authors: Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Nanxincun 20, Xiangshan, Beijing 100093, China.
authors: Weijiang
authors: W
authors: Tang
authors: Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Nanxincun 20, Xiangshan, Beijing 100093, China.|CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Beijing 100093, China.
authors: Rongcheng
authors: R
authors: Lin
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D017360:Arabidopsis / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D015536:Down-Regulation; D018506:Gene Expression Regulation, Plant / Q000502:physiology; D018525:Germination / Q000502:physiology*; D005875:Gibberellins / Q000096:biosynthesis; D008027:Light; D006899:Mixed Function Oxygenases / Q000235:genetics / Q000378:metabolism; D051939:Phytochrome B / Q000378:metabolism*; D057445:Plant Dormancy / Q000502:physiology*; D011401:Promoter Regions, Genetic / Q000235:genetics; D012639:Seeds / Q000502:physiology; D015398:Signal Transduction / Q000502:physiology; D014157:Transcription Factors / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; C524391:CIR1 protein, Arabidopsis; C532384:DOG1 protein, Arabidopsis; D005875:Gibberellins; C497952:PHYB protein, Arabidopsis; C545814:REVEILLE1 protein, Arabidopsis; D014157:Transcription Factors; D051939:Phytochrome B; D006899:Mixed Function Oxygenases; C108186:gibberellin 3beta-hydroxylase