Genome-wide analysis of the MYB gene family and its stress-responsive expression under salinity and drought in sesame
摘要
MYB transcription factors are key regulators of plant development and stress responses. Sesame (Sesamum indicum L.), a vital oilseed crop, is notable for its tolerance to drought and salinity. In this study, we identified 148 MYB genes in the sesame genome, all of which contain characteristic MYB domains. These genes showed substantial variation in physicochemical properties, gene structure, and chromosomal location. Subcellular localization analysis showed that most MYB proteins are nuclear, but some are distributed across multiple organelles. Promoter region analysis revealed diverse cis-acting elements related to light responsiveness, hormone signaling, and stress response. Conserved motif analysis indicated both shared and subgroup-specific motif patterns, supporting functional diversification. Phylogenetic classification grouped the SiMYBs into 11 major clades. Expression profiling of five selected genes under drought and salinity treatments highlighted time-dependent and genotype-specific expression patterns. In particular, SiMYB114, SiMYB305, and SiMYB308 emerged as strong candidates for stress-responsive gene regulation. These findings enhance our understanding of the MYB gene family in sesame and provide valuable targets for future genetic improvement toward stress-resilient cultivars.