Functional Analysis of SmMYB39 in Salt Stress Tolerance of Eggplant (Solanum melongena L.)

Eggplant (Solanum melongena L.), a widely cultivated vegetable of the Solanaceae family, faces significant challenges in growth and yield due to soil salinization. This study aimed to investigate the functional role of the transcription factor SmMYB39 in salt stress tolerance in eggplant. This investigation was conducted through the utilization of bioinformatics analysis, quantitative real-time polymerase chain reaction (qRT-PCR), subcellular localization, validation of transcriptional activation activity, Virus-Induced Gene Silencing (VIGS), and protein interactome analysis. Bioinformatics analysis revealed that SmMYB39 has the closest relationship with SlMYB41, and its promoter contains multiple stress-responsive elements. qRT-PCR results demonstrated that SmMYB39 was significantly upregulated after 12 h of salt stress. Subcellular localization results indicated that the SmMYB39 protein is localized in the nucleus and exhibits transcriptional activation activity. Using VIGS, we observed that silencing of SmMYB39 led to reduced salt stress tolerance in eggplant. In addition, we have conducted research on the protein interactome of SmMYB39. In conclusion, our study demonstrates that SmMYB39 is a crucial transcription factor involved in salt stress response and has the potential to enhance salt tolerance in eggplant.