Genome-Wide Identification, Expression, and Molecular Characterization of the CONSTANS-like Gene Family in Seven Orchid Species

The orchid is one of the most distinctive and highly valued flowering plants. Nevertheless, the ( ) gene family plays significant roles in the control of flowering, and its functions in Orchidaceae have been minimally explored. This research identified 68 potential genes within seven orchids' complete genome, divided into three groups (groups I, II, and III) via a phylogenetic tree. The modeled three-dimensional structure and the conserved domains exhibited a high degree of similarity among the orchid proteins. The selection pressure analysis showed that all orchid COLs suffered a strong purifying selection. Furthermore, the orchid genes exhibited functional and structural heterogeneity in terms of collinearity, gene structure, cis-acting elements within their promoters, and expression patterns. Moreover, we identified 50 genes in orchids with a homology to those involved in the transcriptional regulatory network in Arabidopsis. Additionally, the first overexpression of and in protoplasts suggests that they may antagonize the regulation of flowering time and gynostemium development. Our study will undoubtedly provide new resources, ideas, and values for the modern breeding of orchids and other plants.