OsLESV and OsESV1 promote transitory and storage starch biosynthesis to determine rice grain quality and yield  

作　　者：Nannan Dong Guiai Jiao Ruijie Cao Sanfeng Li Shaolu Zhao Yingqing Duan Liuyang Ma Xinwei Li Feifei Lu Hong Wang Shiwen Wang Gaoneng Shao Zhonghua Sheng Shikai Hu Shaoqing Tang Xiangjin Wei Peisong Hu 董楠楠;焦桂爱;操瑞节;李三峰;绍路;段影青;马刘洋;李欣伟;鲁菲菲;王虹;王诗雯;邵高能;圣忠华;胡时开;唐绍清;魏祥进;胡培松(State Key Laboratory of Rice Biology and Breeding,China National Center for Rice Improvement,China National Rice Research Institute,Hangzhou 310006,China)

机构地区：[1]State Key Laboratory of Rice Biology and Breeding,China National Center for Rice Improvement,China National Rice Research Institute,Hangzhou 310006,China

出　　处：《Plant Communications》2024年第7期215-230,共16页植物通讯（英文）

基　　金：supported by the"STI2030-Major Project"of China(2023ZD04072);the National Major Agriculture Science and Technolohy Project of China(NK2022050102);the National Natural Science Foundation of China(32372099 and 32188102);the Innovation Program of Chinese Academy of Agricultural Sciences(CAAS-CACB-202402).

摘　　要：Transitory starch is an important carbon source in leaves,and its biosynthesis and metabolism are closely related to grain quality and yield.The molecular mechanisms controlling leaf transitory starch biosynthesis and degradation and their effects on rice(Oryza sativa)quality and yield remain unclear.Here,we show that OsLESV and OsESV1,the rice orthologs of AtLESV and AtESV1,are associated with transitory starch biosynthesis in rice.The total starch and amylose contents in leaves and endosperms are significantly reduced,and the final grain quality and yield are compromised in oslesv and osesv1 single and oslesv esv1 double mutants.Furthermore,we found that OsLESV and OsESV1 bind to starch,and this binding depends on a highly conserved C-terminal tryptophan-rich region that acts as a starch-binding domain.Importantly,OsLESV and OsESV1 also interact with the key enzymes of starch biosynthesis,granule-bound starch synthase I(GBSSI),GBSSII,and pyruvate orthophosphote dikiase(PPDKB),to maintain their protein stability and activity.OsLESV and OsESV1 also facilitate the targeting of GBSSI and GBSSII from plastid stroma to starch granules.Overexpression of GBSSI,GBSSII,and PPDKB can partly rescue the phenotypic defects of the oslesv and osesv1 mutants.Thus,we demonstrate that OsLESV and OsESV1 play a key role in regulating the biosynthesis of both leaf transitory starch and endosperm storage starch in rice.These findings deepen our understanding of the molecular mechanisms underlying transitory starch biosynthesis in rice leaves and reveal how the transitory starch metabolism affects rice grain quality and yield,providing useful information for the genetic improvement of rice grain quality and yield.

关 键 词：transitory starch starch-binding domain starch biosynthesis leaf starch deficiency rice Oryza sativa 

分 类 号：S511[农业科学—作物学]