The metal tolerance protein OsMTP11 facilitates cadmium sequestration in the vacuoles of leaf vascular cells for restricting its translocation into rice grains  

作　　者：Peng Liu Liang Sun Yu Zhang Yongjun Tan Yuxing Zhu Can Peng Jiurong Wang Huili Yan Donghai Mao Guohua Liang Gang Liang Xiaoxiang Li Yuntao Liang Feng Wang Zhenyan He Wenbang Tang Daoyou Huang Caiyan Chen 

机构地区：[1]Key Laboratory of Agro-Ecological Processes in Subtropical Region,Institute of Subtropical Agriculture,Chinese Academy of Sciences,Changsha 410125,China [2]College of Agronomy,Hunan Agricultural University,Changsha 410128,China [3]Key Laboratory of Plant Resources,Institute of Botany,Chinese Academy of Sciences,Beijing 100093,China [4]Jiangsu Key Laboratory of Crop Genetics and Physiology,Yangzhou University,Yangzhou 225009,China [5]CAS Key Laboratory of Tropical Plant Resources and Sustainable Use,Xishuangbanna Tropical Botanical Garden,Chinese Academy of Sciences,Kunming,Yunnan 650223,China [6]Hunan Rice Research Institute,Hunan Academy of Agricultural Science,Changsha 410125,China [7]Guangxi Key Laboratory of Rice Genetics and Breeding,Rice Research Institute,Guangxi Academy ofAgricultural Sciences,Nanning 530007,China [8]University of Chinese Academy of Sciences,Beijing 100049,China

出　　处：《Molecular Plant》2024年第11期1733-1752,共20页分子植物（英文版）

基　　金：jointly supported by the Strategic Priority Research Program of the CAS(XDA24010404);the National Natural Science Foundation of ChinaNational Natural Science Foundation of China(U19A2026 and 31972490);the Major Program of Natural Science Foundation of Hunan Province(2021JC0007);the Hunan Key Technologies R&D Program Hunan Key Technologies R&D Program(2023NK1010).

摘　　要：Rice(Oryza sativa)provides>20%of the consumed calories in the human diet.However,rice is also a leading source of dietary cadmium(Cd)that seriously threatens human health.Deciphering the genetic network that underlies the grain-Cd accumulation will benefit the development of low-Cd rice and mitigate the effects of Cd accumulation in the rice grain.In this study,we identified a QTL gene,OsCS1,which is allelic to OsMTP11 and encodes a protein sequestering Cd in the leaf during vegetative growth and preventing Cd from being translocated to the grain after heading in rice.OsCS1 is predominantly expressed in leaf vascular parenchyma cells,where it binds to a vacuole-sorting receptor protein OsVSR2 and is translocated intracellularly from the trans-Golgi network to pre-vacuolar compartments and then to the vacuole.In this trafficking process,OsCS1 actively transports Cd into the endomembrane system and sequesters it in the vacuoles.There are natural variations in the promoter of OsCS1 between the indica and japonica rice subspecies.Duplication of a G-box-like motif in the promoter region of the superior allele of OsCS1 from indica rice enhances the binding of the transcription factor OsIRO2 to the OsCS1 promoter,thereby promoting OsCS1 expression.Introgression of this allele into commercial rice varieties could significantly lower grain-Cd levels compared to the inferior allele present in japonica rice.Collectively,our findings offer new insights into the genetic control of leaf-to-grain Cd translocation and provide a novel gene and its superior allele for the genetic improvement of low-Cd variety in rice.

关 键 词：rice OsCS1/OsMTP11 grain Cd TGN–PVC–vacuole transport allelic variation 

分 类 号：S511[农业科学—作物学]