Defective mitochondrial function by mutation in THICK ALEURONE 1 encoding a mitochondrion-targeted single-stranded DNA-binding protein leads to increased aleurone cell layers and improved nutrition in rice  

作　　者：Dong-Qi Li Xiao-Ba Wu Hai-Feng Wang Xue Feng Shi-Juan Yan Sheng-Yang Wu Jin-Xin Liu Xue-Feng Yao Ai-Ning Bai Heng Zhao Xiu-Fen Song Lin Guo Shi-Yong Zhang Chun-Ming Liu 

机构地区：[1]Key Laboratory of Plant Molecular Physiology,Institute of Botany,Chinese Academy of Sciences,Beijing 100093,China [2]University of Chinese Academy of Sciences,Beijing 100864,China [3]Rice Research Institute,Shandong Academy of Agricultural Sciences,Jinan 250100,China [4]Guangdong Key Laboratory for Crop Germplasm Resources Preservation and Utilization,Agro-biological Gene Research Center,Guangdong Academy of Agricultural Sciences,Guangzhou 510640,China [5]lnstitute of Crop Sciences,Chinese Academy of Agricultural Sciences,Beijing 100081,China [6]School of Advanced Agricultural Sciences,Peking University,Beijing 100871,China [7]Innovative Academy of Seed Design,Chinese Academy of Sciences,Beijing 100101,China

出　　处：《Molecular Plant》2021年第8期1343-1361,共19页分子植物（英文版）

基　　金：supported by grants from the Chinese Academy of Sciences Innovation Project"Molecular Modules for Breeding Design"(XDA24010402);the Beijing Municipal Science and Technology Commission Project(Z181100002418010);the CAS-CSIRO Bilateral Collaboration Project(151111KYSB20180049).

摘　　要：Cereal endosperm comprises an outer aleurone and an inner starchy endosperm.Although these two tissues have the same developmental origin,they differ in morphology,cell fate,and storage product accumulation,with the mechanism largely unknown.Here,we report the identification and characterization of rice thick aleurone 1(ta1)mutant that shows an increased number of aleurone cell layers and increased contents of nutritional factors including proteins,lipids,vitamins,dietary fibers,and micronutrients.We identified that the TA1 gene,which is expressed in embryo,aleurone,and subaleurone in caryopses,encodes a mitochondrion-targeted protein with single-stranded DNA-binding activity named OsmtSSB1.Cytological analyses revealed that the increased aleurone cell layers in ta1 originate from a developmental switch of subaleurone toward aleurone instead of starchy endosperm in the wild type.We found that TA1/OsmtSSB1 interacts with mitochondrial DNA recombinase RECA3 and DNA helicase TWINKLE,and downregulation of REC A3 or TWINKLE also leads to ta1-like phenotypes.We further showed that mutation in TA1/OsmtSSB1 causes elevated illegitimate recombinations in the mitochondrial genome,altered mitochondrial morphology,and compromised energy supply,suggesting that the OsmtSSB1-mediated mitochondrial function plays a critical role in subaleur one cell-fate determination in rice.

关 键 词：RICE thick aleurone cell-fate determination nutritional improvement mitochondria 

分 类 号：S511[农业科学—作物学]