文献类型：期刊文献

英文题名：A Single Amino Acid Change in Nramp6 from Sedum Alfredii Hance Affects Cadmium Accumulation

作者：Lu, Zhuchou[1,2] Chen, Shuangshuang[1,2,3] Han, Xiaojiao[1,2] Zhang, Jin[4] Qiao, Guirong[1,2] Jiang, Yugen[5] Zhuo, Renying[1,2] Qiu, Wenmin[1,2]

第一作者：Lu, Zhuchou

通信作者：Zhuo, RY[1];Qiu, WM[1];Zhuo, RY[2];Qiu, WM[2]|[a00058eb5603bedf0c2e1]卓仁英;

机构：[1]Chinese Acad Forestry, State Key Lab Tree Genet & Breeding, Xiangshan Rd, Beijing 100091, Peoples R China;[2]Chinese Acad Forestry, Res Inst Subtrop Forestry, Hangzhou 311400, Peoples R China;[3]Jiangsu Acad Agr Sci, Inst Leisure Agr, Nanjing 210014, Peoples R China;[4]Oak Ridge Natl Lab, Biosci Div, Oak Ridge, TN 37831 USA;[5]Agr Technol Extens Ctr Fuyang Dist, Hangzhou 311400, Peoples R China

年份：2020

卷号：21

期号：9

外文期刊名：INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES

收录：;Scopus(收录号：2-s2.0-85084276396);WOS:【SCI-EXPANDED(收录号:WOS:000535581700140)】；

基金：This research was funded by grant from the National Nonprofit Institute Research Grant of CAF (CAFYBB2019SZ001), the National key program on transgenic Research (2018ZX08020002) and the National Natural Science Foundation of China (No. 31872168) supported this work.

语种：英文

外文关键词：Nramp6; Cadmium accumulation; site-directed mutagenesis; Sedum alfredii Hance

摘要：SaNramp6 in Sedum alfredii encodes a membrane-localized metal transporter. We isolated the SaNramp6h allele from the hyperaccumulating ecotype (HE) of S. alfredii. When this allele was expressed in transgenic yeast and Arabidopsis thaliana, it enhanced their cadmium (Cd) sensitivity by increased Cd transport and accumulation. We isolated another allele, SaNramp6n, from a nonhyperaccumulating ecotype (NHE) of S. alfredii. Amino acid sequence comparisons revealed three amino acid differences between SaNramp6h and SaNramp6n. We investigated the Cd transport activity of the Nramp6 allele, and determined which residues are essential for the transport activity. We conducted structure-function analyses of SaNramp6 based on site-directed mutagenesis and functional assays of the mutants in yeast and Arabidopsis. The three residues that differed between SaNramp6h and SaNramp6n were mutated. Only the L157P mutation of SaNramp6h impaired Cd transport. The other mutations, S218N and T504A, did not affect the transport activity of SaNramp6h, indicating that these residues are not essential for metal selectivity. Transgenic plants overexpressing SaNramp6h(L157P) showed altered metal accumulation in shoots and roots. Our results suggest that the conserved site L157 is essential for the high metal transport activity of SaNramp6h. This information may be useful for limiting or increasing Cd transport by other plant natural resistance associated macrophage protein (NRAMP) proteins.