Genome-Wide Identification Analysis of the R2R3-MYB Transcription Factor Family in for Insights into Drought Stress Responses.

represents a distinctive Orchidaceae plant that is more tolerant than other terrestrial orchids. Studies have shown that many members of the MYB transcription factor (TF) family, especially the R2R3-MYB subfamily, are responsive to drought stress. This study identified 103 ; phylogenetic analysis classified these genes into 22 subgroups with . Structural analysis showed that most genes contained the same motifs, three exons and two introns, and showed a helix-turn-helix 3D structure in each R repeat. However, the members of subgroup 22 contained only one exon and no intron. Collinear analysis revealed that had more orthologous R2R3-MYB genes with wheat than and rice. ratios indicated that most genes were under purifying negative selection pressure. -acting elements analysis revealed that drought-related elements were mainly focused on subgroups 4, 8, 18, 20, 21, and 22, and (S20) contained the most. The transcriptome analysis results showed that expression patterns of most genes were upregulated in leaves in response to slight drought stress and downregulated in roots. Among them, members in S8 and S20 significantly responded to drought stress in . In addition, S14 and S17 also participated in these responses, and nine genes were selected for the real-time reverse transcription quantitative PCR (RT-qPCR) experiment. The results were roughly consistent with the transcriptome. Our results, thus, provide an important contribution to understanding the role of in stress-related metabolic processes.