Exploring the Role of TaERF4a in Enhancing Drought Tolerance and Regulating Dehydrin Gene Expression in Wheat.

Dehydrins (DHNs) belong to the second family of late embryogenesis abundant (LEA) proteins, which are widely distributed in plants. We cloned a SK-type DHN gene named in Zheng yin 1 cultivar of . An ERF-type transcription factor TaERF4a was found to be involved in the regulation of the dehydrin gene in our last report. The stress-responsive ability and dual-luciferase assay demonstrated that TaERF4a positively regulates gene transcription under stress conditions. In this study, we further characterized the role of the transcription factor TaERF4a in plant drought tolerance. heterologously overexpressing exhibited higher survival rate, increased superoxide dismutase (SOD) activity, elevated proline and chlorophyll content, and reduced malondialdehyde (MDA) content under drought conditions. Conversely, silencing in Chinese spring wheat using the virus-induced gene silencing (VIGS) method increased the sensitivity of plants to drought stress. Furthermore, we identified the specific binding site of TaERF4a in the promoter. Electrophoretic mobility shift assay (EMSA) and dual-luciferase reporter assay demonstrated that TaERF4a activates the expression of the dehydrin gene through binding to the DRE -element in its promoter. Taken together, the results of our study indicate that TaERF4a positively regulates the expression of the dehydrin gene and enhances drought tolerance in plants.