Grape BES1 transcription factor gene VvBES1-3 confers salt tolerance in transgenic Arabidopsis

BRI1-EMS-Suppressor 1 (BES1) regulates plant growth, development, and stress resistance, and plays a pivotal role in the brassinosteroid (BR) signal transduction pathway. In this study, a total of 12 BES1 genes were identified in the grape (Vitis vinifera) genome. Phylogenetic, structure, and motif sequence analyses of these genes provided insights into their evolutionary characteristics. Hormone-, stress-, and light-responsive and organ-specific cis-acting elements were identified in VvBES1 gene promoters. Microarray data analysis showed that VvBES1 family members exhibit diverse expression patterns in different organs. Quantitative real-time PCR (qRT-PCR) analysis showed that the expression levels of VvBES1 genes differed in response to BR, methyl jasmonate (MeJA), cold (4 °C), NaCl, and polyethylene glycol (PEG) treatments. The expression of VvBES1-3 was 29-fold higher under salt stress than control at 12 h. Moreover, VvBES1-3-overexpessing Arabidopsis thaliana plants showed lower malondialdehyde content, higher proline content, enhanced antioxidant enzyme (catalase, superoxide dismutase, peroxidase) activities, and higher salt-responsive gene expression levels than wild-type plants under salt stress, indicating that VvBES1-3 overexpression enhances salt stress tolerance in transgenic Arabidopsis. These results will contribute to further understanding the functions of BES1 transcription factors in the abiotic stress response.