A TT1–SCE1 module integrates ubiquitination and SUMOylation to regulate heat tolerance in rice  

作　　者：Hong-Xiao Yu Ying-Jie Cao Yi-Bing Yang Jun-Xiang Shan Wang-Wei Ye Nai-Qian Dong Yi Kan Huai-Yu Zhao Zi-Qi Lu Shuang-Qin Guo Jie-Jie Lei Ben Liao Hong-Xuan Lin 

机构地区：[1]National Key Laboratory of Plant Molecular Genetics,CAS Center for Excellence in Molecular Plant Sciences,Shanghai Institute of Plant Physiology and Ecology,Chinese Academy of Sciences,Shanghai 200032,China [2]University of the Chinese Academy of Sciences,Beijing 100049,China [3]Joint Center for Single Cell Biology,School of Agriculture and Biology,Shanghai Jiao Tong University,Shanghai 200240,China [4]School of Life Science and Technology,ShanghaiTech University,Shanghai 201210,China [5]Guangdong Laboratory for Lingnan Modern Agriculture,Guangzhou 510642,China [6]These authors contributed equally to this article

出　　处：《Molecular Plant》2024年第12期1899-1918,共20页分子植物（英文版）

基　　金：National Natural Science Foundation of China(32388201);Biological Breeding-National Science and Technology Major Project(2023ZD04071);Laboratory of Lingnan Modern Agriculture Project(NT2021002);Chinese Academy of Sciences(159231KYSB20200008);CAS-Croucher Funding Scheme for Joint Laboratories and National Key Laboratory of Plant MolecularGenetics。

摘　　要：Heat stress poses a significant threat to grain yield.As anα2 subunit of the 26S proteasome,TT1 has been shown to act as a critical regulator of rice heat tolerance.However,the heat tolerance mechanisms mediated by TT1 remain elusive.In this study,we unveiled that small ubiquitin-like modifier(SUMO)-conjugating enzyme 1(SCE1),which interacts with TT1 and acts as a downstream component of TT1,is engaged in TT1-mediated 26S proteasome degradation.We showed that SCE1 functions as a negative regulator of heat tolerance in rice,which is associated with its ubiquitination modification.Furthermore,we observed that small heat-shock proteins(sHSPs)such as Hsp24.1 and Hsp40 can undergo SUMOylation mediated by SCE1,leading to increased accumulation of sHSPs in the absence of SCE1.Reducing protein levels of SCE1 significantly enhanced grain yield under high-temperature stress by improving seed-setting rate and rice grain filling capacity.Taken together,these results uncover the critical role of SCE1 in the TT1-mediated heat tolerance pathway by regulating the abundance of sHSPs and SUMOylation,and ultimately modulating rice heat tolerance.These findings underscore the great potential of the TT1–SCE1 module in improving the heat tolerance of crops.

关 键 词：RICE heat tolerance UBIQUITINATION SUMOYLATION heat-shock protein 

分 类 号：S511[农业科学—作物学]