Modulation of the transition to flowering plays an important role in the adaptation to drought. The drought-escape (DE) response allows plants to adaptively shorten their life cycle to make seeds before severe stress leads to death. However, the molecular basis of the DE response is unknown. A screen of different Arabidopsis (Arabidopsis thaliana) flowering time mutants under DE-triggering conditions revealed the central role of the flower-promoting gene GIGANTEA (GI) and the florigen genes FLOWERING LOCUS T (FT) and TWIN SISTER OF FT (TSF) in the DE response. Further screens showed that the phytohormone abscisic acid is required for the DE response, positively regulating flowering under long-day conditions. Drought stress promotes the transcriptional up-regulation of the florigens in an abscisic acid- and photoperiod-dependent manner, so that early flowering only occurs under long days. Along with the florigens, the floral integrator SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1 is also up-regulated in a similar fashion and contributes to the activation of TSF. The DE response was recovered under short days in the absence of the floral repressor SHORT VEGETATIVE PHASE or in GI-overexpressing plants. Our data reveal a key role for GI in connecting photoperiodic cues and environmental stress independently from the central FT/TSF activator CONSTANS. This mechanism explains how environmental cues may act upon the florigen genes in a photoperiodically controlled manner, thus enabling plastic flowering responses.
GIGANTEA enables drought escape response via abscisic acid-dependent activation of the florigens and SUPPRESSOR of OVEREXPRESSION of CONSTANS1 1[c][w] / M. Riboni, M. Galbiati, C. Tonelli, L. Conti. - In: PLANT PHYSIOLOGY. - ISSN 0032-0889. - 162:3(2013), pp. 1706-1719.
|Titolo:||GIGANTEA enables drought escape response via abscisic acid-dependent activation of the florigens and SUPPRESSOR of OVEREXPRESSION of CONSTANS1 1[c][w]|
RIBONI, MATTEO (Primo)
GALBIATI, MASSIMO (Secondo)
TONELLI, CHIARA (Penultimo)
CONTI, LUCIO (Corresponding)
|Parole Chiave:||floweing-locus-T; mads domain protein; arabidopsis-thaliana; pathway integrator; floral initiation; FT protein; reproductive development; transcription factors; circadian-rhytms; plant development|
|Settore Scientifico Disciplinare:||Settore BIO/18 - Genetica|
|Data di pubblicazione:||2013|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1104/pp.113.217729|
|Appare nelle tipologie:||01 - Articolo su periodico|