The transcriptional regulator BBX24 impairs della activity to promote shade avoidance in Arabidopsis thaliana

• Autores: Crocco, Carlos Daniel; Locascio, Antonella; Escudero, Cristian M.; Alabadí, David; Blázquez, Miguel A.; Botto, Javier Francisco
• Año de publicación: 2015
• Idioma: inglés
• Tipo de recurso: artículo
• Fuente: Nature Communications; Vol.6; art.6202; http://www.nature.com/index.html
• Materia: WHITE LIGHT; UPREGULATION; UNCLASSIFIED DRUG; TRANSIENT EXPRESSION; TRANSCRIPTION FACTOR BBX24; TRANSCRIPTION FACTOR; STRESS; SIGNALING; SIGNAL TRANSDUCTION; SHADE TOLERANCE; SHADE; SEEDLING; SECONDARY METABOLISM; REVERSE TRANSCRIPTION POLYMERASE CHAIN REACTION; PROTEIN PROTEIN INTERACTION; PROTEIN FUNCTION; PROTEIN DEGRADATION; PROTEIN; PROMOTER REGION; PLANT GROWTH; PHOTOPERIODICITY; PHENOTYPE; NONHUMAN; NICOTIANA BENTHAMIANA; MOLECULAR ANALYSIS; LIGHT QUALITY; LIGHT EFFECT; HORMONE METABOLISM; HERB; GLUCOCORTICOID RECEPTOR; GIBBERELLIN; GENOTYPE; GENE REPRESSION; GENE CONTROL; ETHYLENE; EPIDERMIS CELL; DNA BINDING; DELLA PROTEIN; CONTROLLED STUDY; CIRCADIAN RHYTHM; CHROMATIN IMMUNOPRECIPITATION; CELL EXPANSION; BRASSINOSTEROID; BIODEGRADATION; AUXIN TRANSPORT; AUXIN; ARABIDOPSIS THALIANA; ALLELE
• Institución: Universidad de Buenos Aires. Facultad de Agronomía

Fil: Crocco, Carlos Daniel. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura (IFEVA). Buenos Aires, Argentina.
Fil: Crocco, Carlos Daniel. CONICET – Universidad de Buenos Aires. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura (IFEVA). Buenos Aires, Argentina.
Fil: Escudero, Cristian M. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura (IFEVA). Buenos Aires, Argentina.
Fil: Escudero, Cristian M. CONICET – Universidad de Buenos Aires. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura (IFEVA). Buenos Aires, Argentina.
Fil: Botto, Javier Francisco. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura (IFEVA). Buenos Aires, Argentina.
Fil: Botto, Javier Francisco. CONICET – Universidad de Buenos Aires. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura (IFEVA). Buenos Aires, Argentina.
In response to canopy shade, plant vegetative structures elongate to gain access to light. However, the mechanism that allows a plastic transcriptional response to canopy shade light is not fully elucidated. Here we propose that the activity of PIF4, a key transcription factor in the shade signalling network, is modulated by the interplay between the BBX24 transcriptional regulator and DELLA proteins, which are negative regulators of the gibberellin (GA) signalling pathway. We show that GA-related targets are enriched among genes responsive to BBX24 under shade and that the shade-response defect in bbx24 mutants is rescued by a GA treatment that promotes DELLA degradation. BBX24 physically interacts with DELLA proteins and alleviates DELLA-mediated repression of PIF4 activity. The proposed molecular mechanism provides reversible regulation of the activity of a key transcription factor that may prove especially relevant under fluctuating light conditions.