The Effects of High Steady State Auxin Levels on Root Cell Elongation in Brachypodium.

Détails

ID Serval
serval:BIB_039E942D5707
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Institution
Titre
The Effects of High Steady State Auxin Levels on Root Cell Elongation in Brachypodium.
Périodique
The Plant cell
Auteur(s)
Pacheco-Villalobos D., Díaz-Moreno S.M., van der Schuren A., Tamaki T., Kang Y.H., Gujas B., Novak O., Jaspert N., Li Z., Wolf S., Oecking C., Ljung K., Bulone V., Hardtke C.S.
ISSN
1532-298X (Electronic)
ISSN-L
1040-4651
Statut éditorial
Publié
Date de publication
05/2016
Peer-reviewed
Oui
Volume
28
Numéro
5
Pages
1009-1024
Langue
anglais
Notes
Publication types: Journal Article
Publication Status: ppublish
Résumé
The long-standing Acid Growth Theory of plant cell elongation posits that auxin promotes cell elongation by stimulating cell wall acidification and thus expansin action. To date, the paucity of pertinent genetic materials has precluded thorough analysis of the importance of this concept in roots. The recent isolation of mutants of the model grass species Brachypodium distachyon with dramatically enhanced root cell elongation due to increased cellular auxin levels has allowed us to address this question. We found that the primary transcriptomic effect associated with elevated steady state auxin concentration in elongating root cells is upregulation of cell wall remodeling factors, notably expansins, while plant hormone signaling pathways maintain remarkable homeostasis. These changes are specifically accompanied by reduced cell wall arabinogalactan complexity but not by increased proton excretion. On the contrary, we observed a tendency for decreased rather than increased proton extrusion from root elongation zones with higher cellular auxin levels. Moreover, similar to Brachypodium, root cell elongation is, in general, robustly buffered against external pH fluctuation in Arabidopsis thaliana However, forced acidification through artificial proton pump activation inhibits root cell elongation. Thus, the interplay between auxin, proton pump activation, and expansin action may be more flexible in roots than in shoots.

Mots-clé
Brachypodium/metabolism, Cell Wall/metabolism, Galactans/metabolism, Indoleacetic Acids/metabolism, Plant Roots/metabolism, Signal Transduction/physiology
Pubmed
Web of science
Open Access
Oui
Création de la notice
31/05/2016 16:56
Dernière modification de la notice
20/08/2019 12:25
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