Arabidopsis DET1 Represses Photomorphogenesis in Part by Negatively Regulating DELLA Protein Abundance in Darkness
Arabidopsis DET1 Represses Photomorphogenesis in Part by Negatively Regulating DELLA Protein Abundance in Darkness
复制标题
拟南芥 DET1 通过负调节黑暗中 DELLA 蛋白丰度部分抑制光形态发生
DOI：
10.1016/j.molp.2014.12.017
复制
发表时间：
2015-04-06
期刊：
影响因子：
27.5
通讯作者：
Chen, Haodong
中科院分区：
文献类型：
--
作者：
Li, Kunlun;Gao, Zhaoxu;Chen, Haodong
拟南芥去黄化蛋白1（DET 1）是在黑暗条件下维持幼苗黄化状态的关键阻遏蛋白之一。植物激素赤霉酸（GA）也参与了这一过程，缺乏GA合成或信号传导的植物在黑暗中表现出部分去黄化的表型。然而，DET 1和GA途径如何协同抑制光形态建成仍然是未知的。在这项研究中，我们发现，DELLA蛋白的丰度在det 1 -1中增加相比，在野生型植物。DET 1基因突变改变了突变体幼苗下胚轴伸长对GA和GA合成抑制剂多效唑（PAC）的敏感性。然而，我们没有发现det 1 -1和野生型植物之间的生物活性GA含量或GA信号上游的DELLA的明显差异。遗传数据显示，去除几种DELLA蛋白比GA处理更明显地抑制了det 1 -1突变体表型，表明DET 1可以通过其他机制调节DELLA蛋白。此外，一个大规模的转录组学分析表明，DET 1和DELLA发挥拮抗作用，在调控光合和细胞伸长相关基因在黄化幼苗的表达。总之，我们的研究结果表明，DET 1抑制光形态建成在黑暗中的一部分，通过减少DELLA蛋白的丰度。
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 pathwaywork 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.