title: Arabidopsis DET1 represses photomorphogenesis in part by negatively regulating DELLA protein abundance in darkness.
abstract: Arabidopsis De-etiolated 1 (DET1) is one of the key repressors that maintain the etiolated state of seedlings in darkness. The plant hormone gibberellic acid (GA) also participates in this process, and plants deficient in GA synthesis or signaling show a partially de-etiolated phenotype in darkness. However, how DET1 and the GA pathway work in concert in repressing photomorphogenesis remains largely unknown. In this study, we found that the abundance of DELLA proteins in det1-1 was increased in comparison with that in the wild-type plants. Mutation in DET1 changed the sensitivity of hypocotyl elongation of mutant seedlings to GA and paclobutrazol (PAC), an inhibitor of GA synthesis. However, we did not find obvious differences between det1-1 and wild-type plants with regard to the bioactive GA content or the GA signaling upstream of DELLAs. Genetic data showed that removal of several DELLA proteins suppressed the det1-1 mutant phenotype more obviously than GA treatment, indicating that DET1 can regulate DELLA proteins via some other mechanisms. In addition, a large-scale transcriptomic analysis revealed that DET1 and DELLAs play antagonistic roles in regulating expression of photosynthetic and cell elongation-related genes in etiolated seedlings. Taken together, our results show that DET1 represses photomorphogenesis in darkness in part by reducing the abundance of DELLA proteins.
authors.affiliation: Peking-Yale Joint Center for Plant Molecular Genetics and Agro-biotechnology, State Key Laboratory of Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences, College of Life Sciences, Peking University, Beijing 100871, China.
authors.forename: Kunlun
authors.initials: K
authors.lastname: Li
authors.affiliation: Peking-Yale Joint Center for Plant Molecular Genetics and Agro-biotechnology, State Key Laboratory of Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences, College of Life Sciences, Peking University, Beijing 100871, China.
authors.forename: Zhaoxu
authors.initials: Z
authors.lastname: Gao
authors.affiliation: Peking-Yale Joint Center for Plant Molecular Genetics and Agro-biotechnology, State Key Laboratory of Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences, College of Life Sciences, Peking University, Beijing 100871, China.
authors.forename: Hang
authors.initials: H
authors.lastname: He
authors.affiliation: Department of Biology, Wilkes University, Wilkes-Barre, PA 18766, USA.
authors.forename: William
authors.initials: W
authors.lastname: Terzaghi
authors.affiliation: Peking-Yale Joint Center for Plant Molecular Genetics and Agro-biotechnology, State Key Laboratory of Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences, College of Life Sciences, Peking University, Beijing 100871, China.
authors.forename: Liu-Min
authors.initials: LM
authors.lastname: Fan
authors.affiliation: Peking-Yale Joint Center for Plant Molecular Genetics and Agro-biotechnology, State Key Laboratory of Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences, College of Life Sciences, Peking University, Beijing 100871, China; Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, CT 06520-8104, USA. Electronic address: xingwang.deng@yale.edu.
authors.forename: Xing Wang
authors.initials: XW
authors.lastname: Deng
authors.affiliation: Peking-Yale Joint Center for Plant Molecular Genetics and Agro-biotechnology, State Key Laboratory of Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences, College of Life Sciences, Peking University, Beijing 100871, China. Electronic address: chenhaodong@pku.edu.cn.
authors.forename: Haodong
authors.initials: H
authors.lastname: Chen
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D003624:Darkness; D005875:Gibberellins / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins; D009024:Morphogenesis / Q000235:genetics / Q000502:physiology; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D010937:Plant Growth Regulators / Q000378:metabolism; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology
chemical_list: D029681:Arabidopsis Proteins; C088435:DET1 protein, Arabidopsis; C109555:GAI protein, Arabidopsis; D005875:Gibberellins; D047908:Intracellular Signaling Peptides and Proteins; D009687:Nuclear Proteins; D010937:Plant Growth Regulators; C007842:gibberellic acid
keywords: Arabidopsis; DELLA; DET1; gibberellic acid (GA); photomorphogenesis