VvNAC17, a grape NAC transcription factor, regulates plant response to drought-tolerance and anthocyanin synthesis.

NAC transcription factors are unique to plants and play a role in stress. In this study, the VvNAC17 gene was isolated from grapes, and tested the functions of VvNAC17 under drought stress. The expression level of VvNAC17 in callus could be highly induced by drought stress. VvNAC17 overexpression in callus conferred drought-resistant phenotypes with lower MDA content, higher antioxidant enzyme activity (CAT, POD, SOD), higher monomer anthocyanin content, and higher expression levels of some drought-related genes (VvDREB1A, VvDREB2A, VvDREB2D, VvRD29A, VvPIN5) and anthocyanin-biosynthesis-related genes (VvUFGT, VvANS, VvANR, VvDFR,VvLAR). Meanwhile, the Y1H and Dual-LUC assays showed that VvNAC17 could activate VvDREB1A and VvUFGT expression by binding to its promoter. Futhermore, RNA-seq showed that VvNAC17 can affect grape growth and development by affecting the photosynthesis and metabolism of some macromolecules. Taken together, the NAC transcription factor VvNAC17 could positively regulates drought-tolerance. VvNAC17 is a promising candidate for improving drought resistance in grape.