A hormonal regulatory module that provides flexibility to tropic responses.

Détails

ID Serval
serval:BIB_180F6421AAD5
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Institution
Titre
A hormonal regulatory module that provides flexibility to tropic responses.
Périodique
Plant Physiology
Auteur⸱e⸱s
Gallego-Bartolomé J., Kami C., Fankhauser C., Alabadí D., Blázquez M.A.
ISSN
1532-2548 (Electronic)
ISSN-L
0032-0889
Statut éditorial
Publié
Date de publication
2011
Volume
156
Numéro
4
Pages
1819-1825
Langue
anglais
Résumé
Plants orient their growth depending on directional stimuli such as light and gravity, in a process known as tropic response. Tropisms result from asymmetrical accumulation of auxin across the responding organ relative to the direction of the stimulus, which causes differential growth rates on both sides of the organ. Here, we show that gibberellins (GAs) attenuate the gravitropic reorientation of stimulated hypocotyls of dark-grown Arabidopsis (Arabidopsis thaliana) seedlings. We show that the modulation occurs through induction of the expression of the negative regulator of auxin signaling INDOLE-3-ACETIC ACID INDUCIBLE19/MASSUGU2. The biological significance of this regulatory mechanism involving GAs and auxin seems to be the maintenance of a high degree of flexibility in tropic responses. This notion is further supported by observations that GA-deficient seedlings showed a much lower variance in the response to gravity compared to wild-type seedlings and that the attenuation of gravitropism by GAs resulted in an increased phototropic response. This suggests that the interplay between auxin and GAs may be particularly important for plant orientation under competing tropic stimuli.
Mots-clé
Arabidopsis/drug effects, Arabidopsis/genetics, Arabidopsis Proteins/genetics, Arabidopsis Proteins/metabolism, Gene Expression Regulation, Plant/drug effects, Gibberellins/pharmacology, Gravitropism/drug effects, Gravitropism/physiology, Hypocotyl/drug effects, Hypocotyl/physiology, Mutation/genetics, Repressor Proteins/metabolism
Pubmed
Web of science
Open Access
Oui
Création de la notice
09/05/2011 8:25
Dernière modification de la notice
20/08/2019 13:48
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