Plant Cell Journal of Integrative Plant Biology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
QUICK SEARCH:   [advanced]


     

Plant Cell Advance Online Publication
Published on December 4, 2009; 10.1105/tpc.109.070557

This Article
Right arrow Full Text - TPC Advance Online Pub. (PDF)
Right arrow Supplemental Data
Right arrow All Versions of this Article:
21/12/4018    most recent
tpc.109.070557v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Gebert, M.
Right arrow Articles by Knoop, V.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Gebert, M.
Right arrow Articles by Knoop, V.
Agricola
Right arrow Articles by Gebert, M.
Right arrow Articles by Knoop, V.

Received August 6, 2009
Returned for revision October 28, 2009
Accepted November 17, 2009

A Root-Expressed Magnesium Transporter of the MRS2/MGT Gene Family in Arabidopsis thaliana Allows for Growth in Low-Mg2+ Environments

Michael Gebert 1, Karoline Meschenmoser 1, Sona Svidová 2, Julian Weghuber 2, Rudolf Schweyen 2, Karolin Eifler 1, Henning Lenz 1, Katrin Weyand 1, and Volker Knoop 1*

1 Institut für Zelluläre und Molekulare Botanik, Universität Bonn, D-53115 Bonn, Germany
2 Vienna Biocenter, Abteilung für Mikrobiologie und Genetik, A-1030 Wien, Austria

* To whom correspondence should be addressed. E-mail: volker.knoop{at}uni-bonn.de.

The MRS2/MGT gene family in Arabidopsis thaliana belongs to the superfamily of CorA-MRS2-ALR-type membrane proteins. Proteins of this type are characterized by a GMN tripeptide motif (Gly-Met-Asn) at the end of the first of two C-terminal transmembrane domains and have been characterized as magnesium transporters. Using the recently established mag-fura-2 system allowing direct measurement of Mg2+ uptake into mitochondria of Saccharomyces cerevisiae, we find that all members of the Arabidopsis family complement the corresponding yeast mrs2 mutant. Highly different patterns of tissue-specific expression were observed for the MRS2/MGT family members in planta. Six of them are expressed in root tissues, indicating a possible involvement in plant magnesium supply and distribution after uptake from the soil substrate. Homozygous T-DNA insertion knockout lines were obtained for four members of the MRS2/MGT gene family. A strong, magnesium-dependent phenotype of growth retardation was found for mrs2-7 when Mg2+ concentrations were lowered to 50 μM in hydroponic cultures. Ectopic overexpression of MRS2-7 from the cauliflower mosaic virus 35S promoter results in complementation and increased biomass accumulation. Green fluorescent protein reporter gene fusions indicate a location of MRS2-7 in the endomembrane system. Hence, contrary to what is frequently found in analyses of plant gene families, a single gene family member knockout results in a strong, environmentally dependent phenotype.






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
ASPB Publications THE PLANT CELL PLANT PHYSIOLOGY
Copyright © 2009 by the American Society of Plant Biologists