Genome-Wide Screening of the MYB Genes in Coptis chinensis and Their Roles in Growth, Development, and Heavy Metal Resistance.

Background:Coptis chinensis is a traditional medicinal plant rich in bioactive compounds like berberine, known for its antibacterial, anti-inflammatory, and antioxidant properties. This study aims to analyze the MYB transcription factor family in C. chinensis to better understand their roles in plant growth, development, metabolism, and stress responses. Methods: We employed bioinformatics to conduct a genome-wide identification of MYB genes in C. chinensis, followed by analyses of physicochemical properties, phylogenetic relationships, gene structures, chromosomal localization, conserved motifs, cis-acting elements, and expression patterns. Results were validated using qRT-PCR. Results: A total of 129 CcMYB genes were identified across nine chromosomes. Phylogenetic analysis categorized these genes into 19 subgroups, notably highlighting the S6 subgroup, which lacks counterparts in Arabidopsis. Comparative genomics revealed segmental duplication among gene pairs. Transcriptomic analysis indicated that CcMYB21, CcMYB40, CcMYB105, and CcMYB116 had high expression levels in stems. Importantly, CcMYB94 expression significantly increased under cadmium stress, suggesting its role in stress regulation. Conclusions: This study offers a comprehensive analysis of the MYB gene family in C. chinensis, underscoring the significance of MYB transcription factors in enhancing the plant's medicinal value and stress tolerance, particularly against cadmium exposure. These insights pave the way for further exploration of specific MYB genes to improve stress resilience in C. chinensis.