DELLA Proteins in Signalling

Abstract

DELLAs are a family of nuclear proteins that act as growth repressors throughout the life cycle of higher plants. Derepression is mediated through the gibberellic acid (GA)‐dependent degradation of DELLAs and the key components of the GA‐DELLA signalling pathway (the GA receptor and the F‐box protein involved in DELLA destruction) have recently been identified. It is becoming increasingly clear that DELLAs promote a plant's survival by integrating its growth responses to a wide range of endogenous and environmental signals.

Ethylene: A Master Regulator of Salinity Stress Tolerance in Plants

“…The interaction of GA with ethylene was observed via DELLA proteins only. Moreover, the mutants in which the DELLA protein gene was disrupted by four folds showed improved root growth in high salinity stress, as ethylene suppresses the root growth and GA promotes the same [161].…”

Basal stomatal aperture is regulated by GA-DELLAs in Arabidopsis

“…Therefore, it was possible that the GA-mediated opening of stomata that we observed in the wild type, was due to the degradation of DELLAs mediated by exogenous GA. Taken together, our data suggest that the exogenous GAmediated opening of stomata in the wild-type occurs through the degradation of DELLAs, thus inhibiting DELLA-mediated promotion of closure. DELLA proteins are key negative regulators of gibberellin signalling (Alvey and Boulton, 2008;Murase et al, 2008) and important in plant environmental responses (Achard et al, 2006).…”