Role of SnRK2s in grape berry development and stress response

Abstract

Even though abscisic acid (ABA) plays a significant role in fruit growth and responses to a variety of environmental stimuli, the signaling mechanisms that underpin these activities are unknown. role. In present study, we identified seven sucrose non-fermenting-1-related protein kinases 2 (SnRK2s) from the grape (Vitis vinifera L.) genome, which may localized in the nucleus, membrane, and cytoplasm. The overexpression (OE) of VvSnRK2s showed that VvSnRK2.2 and VvSnRK2.7 promoted the ripening process in strawberries on molecular and physiological levels (fruit weight, berry firmness, cell wall composition, total soluble sugar, titratable acid, pigments, phenolic compounds), furthermore, VvSnRK2.3 and VvSnRK2.6 induced strong resistance in strawberry fruits to B. cinerea. Only VvSnRK2.2 and VvSnRK2.7 were found to interact with VvMYB24, a positive regulator of grape berry ripening. Additionally, VvSnRK2s interact with VvABF1 (an ABA-responsive factor) and VvABI1 (ABA insensitive 1) to mediate the ABA signalling pathway. VvSnRK2s respond to different hormonal treatments and abiotic stresses to improve plant stress resistance. Collectively, our results demonstrated that VvSnRK2.2 and VvSnRK2.7 are positive regulators grape berry development and ripening, while, VvSnRK2.3 and VvSnRK2.6 mediate grape resistance against B. cinerea.