Arabidopsis DE-ETIOLATED1 Represses Photomorphogenesis by Positively Regulating Phytochrome-Interacting Factors in the Dark
Arabidopsis DE-ETIOLATED1 Represses Photomorphogenesis by Positively Regulating Phytochrome-Interacting Factors in the Dark
复制标题
拟南芥 DE-ETIOLATED1 通过在黑暗中正向调节光敏色素相互作用因子来抑制光形态发生
DOI：
10.1105/tpc.114.130666
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发表时间：
2014-09-01
期刊：
影响因子：
11.6
通讯作者：
Chen, Haodong
中科院分区：
文献类型：
--
作者：
Dong, Jie;Tang, Dafang;Chen, Haodong
当光形态发生抑制因子DE-ETIOLATED1(DET1)的功能被破坏时，拟南芥幼苗即使在黑暗中也能进行光形态发生发育。然而，DET1抑制光形态建成的机制尚不清楚。我们的结果表明，DET1直接与一组被称为光敏色素相互作用因子(PIF)的转录因子相互作用。此外，我们的结果表明，DET1主要通过在黑暗中稳定PIF蛋白来积极调节PIF蛋白的水平。遗传分析表明，每个PIF突变体都能增强DET1-1的表型，而根据下胚轴伸长和子叶在黑暗中的张开角度，每个PIF在DET1-1中的异位表达部分抑制了DET1-1的表型。基因组分析还表明，DET1可能部分通过PIF调控光调控基因的表达，从而介导光形态建成。DET1和PIF之间的相互作用和调控不仅揭示了DET1是如何抑制光形态建成的，而且提示了一种可能的机制，即构成光形态发生/DET/FusCA和PIFs的光形态发生抑制因子在黑暗中协同作用抑制光形态建成。
Arabidopsis thaliana seedlings undergo photomorphogenic development even in darkness when the function of DE-ETIOLATED1 (DET1), a repressor of photomorphogenesis, is disrupted. However, the mechanism by which DET1 represses photomorphogenesis remains unclear. Our results indicate that DET1 directly interacts with a group of transcription factors known as the phytochrome-interacting factors (PIFs). Furthermore, our results suggest that DET1 positively regulates PIF protein levels primarily by stabilizing PIF proteins in the dark. Genetic analysis showed that each pif single mutant could enhance the det1-1 phenotype, and ectopic expression of each PIF in det1-1 partially suppressed the det1-1 phenotype, based on hypocotyl elongation and cotyledon opening angles observed in darkness. Genomic analysis also revealed that DET1 may modulate the expression of light-regulated genes to mediate photomorphogenesis partially through PIFs. The observed interaction and regulation between DET1 and PIFs not only reveal how DET1 represses photomorphogenesis, but also suggest a possible mechanism by which two groups of photomorphogenic repressors, CONSTITUTIVE PHOTOMORPHOGENESIS/DET/FUSCA and PIFs, work in concert to repress photomorphogenesis in darkness.