Back to Search
Start Over
Four plasma membrane-localized MGR transporters mediate xylem Mg 2+ loading for root-to-shoot Mg 2+ translocation in Arabidopsis.
- Source :
-
Molecular plant [Mol Plant] 2022 May 02; Vol. 15 (5), pp. 805-819. Date of Electronic Publication: 2022 Jan 19. - Publication Year :
- 2022
-
Abstract
- Magnesium (Mg <superscript>2+</superscript> ), an essential structural component of chlorophyll, is absorbed from the soil by roots and transported to shoots to support photosynthesis in plants. However, the molecular mechanisms underlying root-to-shoot Mg <superscript>2+</superscript> translocation remain largely unknown. We describe here the identification of four plasma membrane (PM)-localized transporters, named Mg <superscript>2+</superscript> release transporters (MGRs), that are critical for root-to-shoot Mg transport in Arabidopsis. Functional complementation assays in a Mg <superscript>2+</superscript> -uptake-deficient bacterial strain confirmed that these MGRs conduct Mg <superscript>2+</superscript> transport. PM-localized MGRs (MGR4, MGR5, MGR6, and MGR7) were expressed primarily in root stellar cells and participated in the xylem loading step of the long-distance Mg <superscript>2+</superscript> transport process. In particular, MGR4 and MGR6 played a major role in shoot Mg homeostasis, as their loss-of-function mutants were hypersensitive to low Mg <superscript>2+</superscript> but tolerant to high Mg <superscript>2+</superscript> conditions. Reciprocal grafting analysis further demonstrated that MGR4 functions in the root to determine shoot Mg <superscript>2+</superscript> accumulation and physiological phenotypes caused by both low- and high-Mg <superscript>2+</superscript> stress. Taken together, our study has identified the long-sought transporters responsible for root-to-shoot Mg <superscript>2+</superscript>  translocation in plants.<br /> (Copyright © 2022 The Author. Published by Elsevier Inc. All rights reserved.)
Details
- Language :
- English
- ISSN :
- 1752-9867
- Volume :
- 15
- Issue :
- 5
- Database :
- MEDLINE
- Journal :
- Molecular plant
- Publication Type :
- Academic Journal
- Accession number :
- 35063662
- Full Text :
- https://doi.org/10.1016/j.molp.2022.01.011