Characterization of a Wheat R2R3-MYB Transcription Factor Gene, TaMYB19, Involved in Enhanced Abiotic Stresses in Arabidopsis

MYB-type proteins have been shown to participate in multiple stress responses. In the present study, we identified a gene in wheat induced by multiple abiotic stresses, TaMYB19, which encodes a R2R3-type MYB protein. Three highly homologous sequences of TaMYB19 were isolated from hexaploid wheat. Using the nulli-tetrasomic (NT) lines of Chinese Spring wheat, the three sequences were localized to chromosomes 1A, 1B and 1D and designated as TaMYB19-A, TaMYB19-B and TaMYB19-D, respectively. The expression patterns of these three genes were similar under different stress conditions. The TaMYB19-B sequence was selected for further analysis. The TaMYB19-B protein localized to the nucleus. A detailed characterization of Arabidopsis transgenic plants overexpressing the TaMYB19-B gene revealed that the TaMYB19-B protein could improve tolerance to multiple stresses during the seedling stage. We also found that the overexpression of TaMYB19-B resulted in changes in several physiological indices and altered the expression levels of a number of abiotic stress-related genes, allowing the plants to overcome adverse conditions. These results indicate that the TaMYB19 protein plays an important role in plant stress tolerance and that modification of the expression of this protein may improve abiotic stress tolerance in crop plants.