Genome-wide identification and expression profiling of the MYC gene family in Triticum monococcum L. subsp. aegilopoides with a focus on the red glume mutant.

Abstract

MYC transcription factors, belonging to the basic helix-loop-helix (bHLH) superfamily, are widely recognized for their critical involvement in controlling various aspects of plant growth, developmental processes, and responses to environmental stresses. Triticum monococcum L. subsp. aegilopoides, a wild diploid wheat species, provides valuable Genetic resources for improving stress tolerance and nutritional traits. In this study, 18 TbMYC genes were identified in T. monococcum L. subsp. aegilopoides, characterized by diverse gene structures, conserved motifs, and distinct tissue-specific expression patterns. Phylogenetic analysis grouped these genes into six groups, revealing unique structural features and motifs that suggest functional diversification. Promoter analysis uncovered numerous cis-regulatory elements linked to light response, stress adaptation, and hormonal regulation, with TbMYC8 notably enriched in ABA-responsive elements, highlighting its potential involvement in abscisic acid-mediated stress responses. Synteny analysis demonstrated conserved TbMYCs across Triticeae species, underscoring their evolutionary significance. RNA-seq analysis identified five TbMYCs significantly implicated in the anthocyanin biosynthetic pathway, particularly in regulating pigment accumulation in a red-glume mutant. These findings underscore the critical roles of TbMYCs in stress adaptation and secondary metabolism, providing valuable insights for wheat improvement and functional genomics.