Drought stress provokes the down-regulation of methionine and ethylene biosynthesis pathways in Medicago truncatula roots and nodules

Author(s)
Estíbaliz Larrainzar, Johanna A Molenaar, Stefanie Wienkoop, Erena Gil-Quintana, Bénédicte Alibert, Anis M Limami, Cesar Arrese-Igor, Esther M González
Abstract

Symbiotic nitrogen fixation is one of the first physiological processes inhibited in legume plants under water-deficit conditions. Despite the progress made in the last decades, the molecular mechanisms behind this regulation are not fully understood yet. Recent proteomic work carried out in the model legume Medicago truncatula provided the first indications of a possible involvement of nodule methionine (Met) biosynthesis and related pathways in response to water-deficit conditions. To better understand this involvement, the drought-induced changes in expression and content of enzymes involved in the biosynthesis of Met, S-adenosyl-L-methionine (SAM) and ethylene in M. truncatula root and nodules were analyzed using targeted approaches. Nitrogen-fixing plants were subjected to a progressive water deficit and a subsequent recovery period. Besides the physiological characterization of the plants, the content of total sulphur, sulphate and main S-containing metabolites was measured. Results presented here show that S availability is not a limiting factor in the drought-induced decline of nitrogen fixation rates in M. truncatula plants and provide evidences for a down-regulation of the Met and ethylene biosynthesis pathways in roots and nodules in response to water-deficit conditions.

Organisation(s)
External organisation(s)
Universidad Pública de Navarra, Wageningen University and Research Centre, Université d'Angers
Journal
Plant, Cell and Environment
Volume
37
Pages
2051-2063
No. of pages
13
ISSN
0140-7791
DOI
https://doi.org/10.1111/pce.12285
Publication date
09-2014
Peer reviewed
Yes
Austrian Fields of Science 2012
106023 Molecular biology, 106030 Plant ecology
Keywords
ASJC Scopus subject areas
Physiology, Plant Science
Portal url
https://ucrisportal.univie.ac.at/en/publications/b93fc054-f3c9-48de-abd9-6832f66ceb0f