Heterologous VvDREB2c Expression Improves Heat Tolerance in Arabidopsis by Inducing Photoprotective Responses.

Extreme temperatures limit grape production and sustainability. Dehydration-responsive element-binding (DREB) transcription factors affect plant responses to temperature related stresses. Therefore, we investigated the role of , a DREB-coding gene, found in grapes ( L.). Protein characterization revealed that VvDREB2c is localized to the nucleus and that its AP2/ERF domain contains three β-sheets and one α-helix sheet. Analysis of the promoter region revealed the presence of light-, hormone-, and stress-related cis-acting elements. Furthermore, we observed that the heterologous expression of in improved growth, drought tolerance, and heat tolerance. Furthermore, it improved the leaf quantum yield of regulated energy dissipation [Y(NPQ)], elevated the activities of RuBisCO, and phosphoenolpyruvate carboxylase and reduced the quantum yield of non-regulated energy dissipation [Y(NO)] in plants exposed to high temperatures. -overexpressing lines also specifically upregulated several photosynthesis-related genes (, , and ). In addition, -overexpressing lines reduced light damage and enhanced photoprotective ability by dissipating excess light energy and converting it into heat, which eventually improves tolerance to high temperature. The contents of abscisic acid, jasmonic acid, and salicylic acid and differentially expressed genes (DEGs) in the mitogen-activated protein kinase (MAPK) signaling pathway were affected by heat stress in -overexpressing lines, which indicated that positively regulates heat tolerance via a hormonal pathway in . promotes heat tolerance in by exerting effects on photosynthesis, hormones, and growth conditions. This study may provide useful insights into the enrichment of the heat-tolerance pathways in plants.