IFEVA 02662
INSTITUTO DE INVESTIGACIONES FISIOLOGICAS Y ECOLOGICAS VINCULADAS A LA AGRICULTURA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Repression of shade-avoidance reactions by sunfleck-induction of HY5 expression.
Autor/es:
SELLARO, ROMINA; CASAL, JORGE JOSÉ
Lugar:
La Plata
Reunión:
Taller; Primera Reunión de Fotobiólogos Moleculares Argentinos; 2011
Resumen:
The light environment provides key signals controlling the growth of the stem in plants. The reduced fluence rate and altered spectral composition of shade-light promote stem growth compared to unfiltered sunlight. However, while most studies have used seedlings exposed to contrasting but constant light treatments, the natural light environment may exhibit strong fluctuations. Due to gaps in the canopy, plants shaded by neighbours may experience sunflecks, i.e. brief periods of exposure to unfiltered sunlight. Here we show that sunflecks are perceived by phytochromes A and B and inhibit hypocotyl growth in Arabidopsis thaliana mainly if they occur during the final portion of the photoperiod. By using forward and reverse genetic approaches we found that ELONGATED HYPOCOTYL 5, LATE ELONGATED HYPOCOTYL, PHYTOCHROME KINASE SUBSTRATE 4 and auxin signalling are key players in this response.
