Knockout of a rice K5.2 gene increases Ca accumulation in the grain  

作　　者：Peitong Wang Naoki Yamaji Namiki Mitani-Ueno Jun Ge Jian Feng Ma 

机构地区：[1]National Key Laboratory of Crop Genetics&Germplasm Enhancement and Utilization,College of Resources and Environmental Sciences,Nanjing Agricultural University,Nanjing 210095,China [2]Institute of Plant Science and Resources,Okayama University,Kurashiki 710-0046,Japan

出　　处：《Journal of Integrative Plant Biology》2024年第2期252-264,共13页植物学报（英文版）

基　　金：supported by the Japan Society for the Promotion of Science(JSPS)(KAKENHI grant nos.21H05034 and 21F21096 to J.F.M.,and 19H03250 to N.Y.)。

摘　　要：Rice is a staple food for half of the world’s population,but it is a poor dietary source of calcium(Ca)due to the low concentration.It is an important issue to boost Ca concentration in this grain to improve Ca deficiency risk,but the mechanisms underlying Ca accumulation are poorly understood.Here,we obtained a rice(Oryza sativa)mutant with high shoot Ca accumulation.The mutant exhibited 26%-53% higher Ca in shoots than did wild-type rice(WT)at different Ca supplies.Ca concentration in the xylem sap was 36% higher in the mutant than in the WT.There was no difference in agronomic traits between the WT and mutant,but the mutant showed 25% higher Ca in the polished grain compared with the WT.Map-based cloning combined with a complementation test revealed that the mutant phenotype was caused by an 18-bp deletion of a gene,OsK5.2,belonging to the Shaker-like K+channel family.OsK5.2 was highly expressed in the mature region of the roots and its expression in the roots was not affected by Ca levels,but upregulated by low K.Immunostaining showed that OsK5.2 was mainly expressed in the pericycle of the roots.Taken together,our results revealed a novel role for OsK5.2 in Ca translocation in rice,and will be a good target for Ca biofortification in rice.

关 键 词：ACCUMULATION BIOFORTIFICATION calcium OsK5.2 pericycle RICE TRANSLOCATION 

分 类 号：S511[农业科学—作物学]