Genome-Wide Identification and Analysis of Gene Family among Three Species.

orchids, which are among the most well-known species of orchids, are appreciated for their aesthetic appeal across the globe. Furthermore, due to their strict living conditions, they have accumulated high levels of active ingredients, resulting not only in their medicinal value but also in their strong ability to respond to harsh environments. The gene family plays an important role in plant growth and development, and signal transduction. However, these genes have not been systematically investigated in species. In this study, we detected a total of 24, 23, and 14 candidate members in the genome sequences of , , and , respectively. These genes were classified into three clades on the basis of a phylogenetic analysis. The gene numbers among species were still highly variable due to the independent loss of genes in the CIN clade. However, only three gene duplication events were detected, with only one tandem duplication event (/) in and two pairs of paralogous gene duplication events (/ and /) in . A total of 25 -acting elements of s related to hormone/stress and light responses were detected. Among them, the proportions of hormone response, light response, and stress response elements in (100/421, 127/421, and 171/421) were similar to those in (83/352, 87/352, and 161/352). Using qRT-PCR to determine their expression patterns under MeJA treatment, four s (, , , and ) were significantly upregulated under MeJA treatment, which indicates that genes may play important roles in responding to stress. Under ABA treatment, seven s (, , , , , , and ) were significantly upregulated, indicating that genes may also play an important role in hormone response. Therefore, these results can provide useful information for studying the evolution and function of genes in species.