An Arabidopsis vasculature distributed metal tolerance protein facilitates xylem magnesium diffusion to shoots under high-magnesium environments  

作　　者：Haiman Ge Yuan Wang Jinlin Chen Bin Zhang Rui Chen Wenzhi Lan Sheng Luan Lei Yang 

机构地区：[1]Nanjing University–Nanjing Forestry University Joint Institute for Plant Molecular Biology,College of Life Sciences,Nanjing University,Nanjing 210093,China [2]Shanghai Center for Plant Stress Biology,CAS Center for Excellence in Molecular Plant Sciences,Shanghai 201602,China [3]Chinese Education Ministry’s Key Laboratory of Western Resources and Modern Biotechnology,Key Laboratory of Biotechnology Shaanxi Province,College of Life Sciences,Northwest University,Xi'an 710069,China [4]Department of Plant and Microbial Biology,University of California,Berkeley,California 94702,USA

出　　处：《Journal of Integrative Plant Biology》2022年第1期166-182,共17页植物学报（英文版）

基　　金：supported by the Natural Science Foundation of Shandong Province(ZR2020MC160);China Postdoctoral Foundation(2019M661647)。

摘　　要：Magnesium(Mg^(2+)) is an essential metal for plant growth;however, its over-accumulation in cells can be cytotoxic. The metal tolerance protein family(MTP) belongs to an ubiquitous family of cation diffusion facilitator(CDF) proteins that export divalent metal cations for metal homeostasis and tolerance in all organisms. We describe here the identification of MTP10 to be critical for xylem Mg homeostasis in Arabidopsis under high Mg^(2+) conditions. The Arabidopsis plant contains 12 MTP genes, and only knockout of MTP10 decreased the tolerance of high-Mg stress. The functional complementation assays in a Mg^(2+)-uptake-deficient bacterial strain MM281 confirmed that MTP10 conducted Mg;transport.MTP10 is localized to the plasma membrane of parenchyma cells around the xylem. Reciprocal grafting analysis further demonstrated that MTP10 functions in the shoot to determine the shoot growth phenotypes under high Mg^(2+) conditions.Moreover, compared to the wild type, the mtp10 mutant accumulated more Mg^(2+) in xylem sap under high-Mg stress. This study reveals that MTP10 facilitates Mg^(2+) diffusion from the xylem to shoots and thus determines Mg homeostasis in shoot vascular tissues during high-Mg stress.

关 键 词：allocation ARABIDOPSIS Mg^(2+)toxicity root-to-shoot translocation 

分 类 号：Q945[生物学—植物学]