Dual involvement of a Medicago truncatula NAC transcription factor in root abiotic stress response and symbiotic nodule senescence. - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Plant Journal Année : 2012

Dual involvement of a Medicago truncatula NAC transcription factor in root abiotic stress response and symbiotic nodule senescence.

Axel de Zélicourt
  • Fonction : Auteur
Anouck Diet
  • Fonction : Auteur
Carole Laffont
  • Fonction : Auteur
  • PersonId : 1205165
Federico Ariel
Michaël Moison
  • Fonction : Auteur
  • PersonId : 769133
  • IdRef : 183327950
Ons Zahaf
  • Fonction : Auteur
Martin Crespi
Véronique Gruber
  • Fonction : Auteur
Florian Frugier

Résumé

Legume crops related to the model plant Medicago truncatula can adapt their root architecture to environmental conditions, both by branching and by establishing a symbiosis with rhizobial bacteria to form nitrogen-fixing nodules. Soil salinity is a major abiotic stress affecting plant yield and root growth. Previous transcriptomic analyses identified several transcription factors linked to the M. truncatula response to salt stress in roots, including NAC (NAM/ATAF/CUC)-encoding genes. Over-expression of one of these transcription factors, MtNAC969, induced formation of a shorter and less-branched root system, whereas RNAi-mediated MtNAC969 inactivation promoted lateral root formation. The altered root system of over-expressing plants was able to maintain its growth under high salinity, and roots in which MtNAC969 was down-regulated showed improved growth under salt stress. Accordingly, expression of salt stress markers was decreased or induced in MtNAC969 over-expressing or RNAi roots, respectively, suggesting a repressive function for this transcription factor in the salt-stress response. Expression of MtNAC969 in central symbiotic nodule tissues was induced by nitrate treatment, and antagonistically affected by salt in roots and nodules, similarly to senescence markers. MtNAC969 RNAi nodules accumulated amyloplasts in the nitrogen-fixing zone, and were prematurely senescent. Therefore, the MtNAC969 transcription factor, which is differentially affected by environmental cues in root and nodules, participates in several pathways controlling adaptation of the M. truncatula root system to the environment.
Fichier non déposé

Dates et versions

hal-00855577 , version 1 (29-08-2013)

Identifiants

Citer

Axel de Zélicourt, Anouck Diet, Jessica Marion, Carole Laffont, Federico Ariel, et al.. Dual involvement of a Medicago truncatula NAC transcription factor in root abiotic stress response and symbiotic nodule senescence.. Plant Journal, 2012, 70 (2), pp.220-30. ⟨10.1111/j.1365-313X.2011.04859.x⟩. ⟨hal-00855577⟩
31 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More