近日，中国科学院遗传与发育生物学研究所王冰等研究人员合作揭示水稻中独角金内酯感知的调控机制。相关论文于2024年11月4日在线发表在《细胞》杂志上。
研究人员表示，独角金内酯（SL）是植物发育和环境响应中必不可少的激素。SL的感知需要由榄香烯受体DWARF14（D14）、F-box蛋白D3和转录抑制因子D53组成的复合物，触发D53的泛素化和降解，从而激活信号转导。然而，SL感知的机制及其对植物结构和环境响应的影响仍不清楚且存在争议。
研究人员报告了AtD14-D3-ASK1复合物接口上的关键残基对SL感知激活的重要性，发现D3-CTH基序的过表达通过负向调控SL感知来增强分蘖，并揭示了磷酸化和N端无序（NTD）结构域在介导D14的泛素化和降解中的重要作用。
重要的是，低氮促进D14的磷酸化和稳定性，从而抑制水稻的分蘖。这些发现揭示了SL感知的激活、终止和调控全景，并决定了植物在复杂环境中的结构可塑性。
附：英文原文
Title: Regulatory mechanisms of strigolactone perception in rice
Author: Qingliang Hu, Huihui Liu, Yajun He, Yanrong Hao, Jijun Yan, Simao Liu, Xiahe Huang, Zongyun Yan, Dahan Zhang, Xinwei Ban, Hao Zhang, Qianqian Li, Jingkun Zhang, Peiyong Xin, Yanhui Jing, Liquan Kou, Dajun Sang, Yonghong Wang, Yingchun Wang, Xiangbing Meng, Xiangdong Fu, Jinfang Chu, Bing Wang, Jiayang Li
Issue&Volume: 2024-11-04
Abstract: Strigolactones (SLs) are hormones essential for plant development and environmental responses. SL perception requires the formation of the complex composed of an SL receptor DWARF14 (D14), F-box protein D3, and transcriptional repressor D53, triggering ubiquitination and degradation of D53 to activate signal transduction. However, mechanisms of SL perception and their influence on plant architecture and environmental responses remain elusive and controversial. Here, we report that key residues at interfaces of the AtD14-D3-ASK1 complex are essential for the activation of SL perception, discover that overexpression of the D3-CTH motif negatively regulates SL perception to enhance tillering, and reveal the importance of phosphorylation and N-terminal disordered (NTD) domain in mediating ubiquitination and degradation of D14. Importantly, low nitrogen promotes phosphorylation and stabilization of D14 to repress rice tillering. These findings reveal a panorama of the activation, termination, and regulation of SL perception, which determines the plasticity of plant architecture in complex environments.
DOI: 10.1016/j.cell.2024.10.009
Source: https://www.cell.com/cell/abstract/S0092-8674(24)01157-7