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
• 来源期刊: 植物学报（英文版）
• 年，卷（期）: 2022,（1）
• 所属期刊栏目: Plant-abiotic Interactions
• 页码范围: 166-182
• 页数: 17页
• 语种: 英文

摘要

Magnesium (Mg2+) 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 ex-port 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 Mg2+conditions.The Arabidopsis plant contains 12 MTP genes,and only knockout of MTP10 de-creased the tolerance of high-Mg stress.The functional complementation assays in a Mg2+-uptake-deficient bacterial strain MM281 con-firmed that MTP10 conducted Mg2+ 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 Mg2+ conditions.Moreover,compared to the wild type,the mtp10 mutant accumulated more Mg2+ in xylem sap under high-Mg stress.This study reveals that MTP10 facilitates Mg2+ diffusion from the xylem to shoots and thus determines Mg homeostasis in shoot vascular tissues during high-Mg stress.