摘要
独脚金内酯(strigolactone,SL)是调控植物分枝等重要生长发育过程的新型植物激素。水稻(Oryza sativa)中SL受体D14感知SL信号,结合F-box蛋白D3并招募转录抑制子D53,诱导D53泛素化降解,从而触发信号传递、抑制分蘖。最近的一项研究发现,低氮信号诱导D14的N端无序区(NTD)特异位点发生磷酸化修饰,造成D14的泛素化降解减弱,从而增强SL信号通路。此外,低氮信号本身可以诱导SL合成,通过这两种机制的协同作用强化SL信号转导,从而强烈抑制分蘖,使水稻适应低氮逆境。该研究还发现,SL诱导的D14-D3相互作用也促进了D14的泛素化降解,从而介导SL信号感知的终止。这些重要发现阐明了水稻中SL信号感知的激活和终止机制,揭示了SL信号在控制水稻分蘖以适应低氮逆境中的重要作用,为理解植物如何适应营养匮乏等外界环境变化提供了新的重要见解,对作物株型的精准改良以及减肥增产水稻分子设计育种具有重要指导意义。
Strigolactone(SL)is a novel plant hormone that regulates important growth and developmental processes such as plant branching.In rice,the SL receptor D14 perceives SL signals,binds with the F-box protein D3,and recruits the transcriptional repressor D53,inducing the ubiquitination and degradation of D53,thereby triggering signal transduction and inhibiting tillering.A recent study discovered that nitrogen limitation induces SL biosynthesis in rice to activate the receptor D14,triggering SL signal transduction.Concurrently,nitrogen limitation also induces phosphorylation of the N-terminal disordered region(NTD)of D14,reducing the ubiquitination and degradation of receptor D14,thereby further enhancing SL perception.Through these two synergistic mechanisms,nitrogen limitation stimulates SL signal transduction,strongly inhibiting tillering and enabling rice to adapt to low nitrogen stress conditions.The study also found that the D14-D3 interaction induced by SL promotes the ubiquitination and degradation of D14,thereby mediating the termination of SL signal perception.These significant findings elucidate the mechanisms of activation and termination of SL perception in rice,revealing the crucial regulatory role of SL signals in controlling rice tillering under low nitrogen stress.This would provide key insights into plant adaptation to nutrient scarcity and guide the precise improvement of crop architecture and molecular breeding of rice for reduced fertilizer use and increased yield.
作者
姚瑞枫
谢道昕
Ruifeng Yao;Daoxin Xie(Hunan Provincial Key Laboratory of Plant Functional Genomics and Developmental Regulation,State Key Laboratory of Chemo/Biosensing and Chemometrics,College of Biology,Hunan University,Changsha 410082,China;MOE Key Laboratory of Bioinformatics,Tsinghua-Peking Joint Center for Life Sciences,School of Life Sciences,Tsinghua University,Beijing 100084,China)
出处
《植物学报》
CAS
CSCD
北大核心
2024年第6期873-877,共5页
Chinese Bulletin of Botany
基金
国家重点研发计划青年科学家项目(No.2022YFF1002000)。
关键词
水稻
独脚金内酯
受体D14
低氮信号
磷酸化
泛素化
rice
strigolactone
receptor D14
nitrogen limitation
phosphorylation
ubiquitination
