Genome-Wide Identification of the PEBP Family Gene in Three Cymbidium Species and Its Expression Patterns Analysis in C. ensifolium

The PEBP gene family is involved in many biological processes in plants, including plant growth and development, flowering regulation, light response, and abiotic stress response. But there is little information about the role of the PEBP gene family in Cymbidium species. In this study, we identified 11, 9, and 7 PEBP genes in C. ensifolium, C. sinense, and C. goeringii, respectively, and mapped them to the chromosomes. We also studied the physicochemical characteristics of the proteins encoded by these PEBPs and analyzed their intra-species collinearity, gene structure, conserved motifs, and cis-acting elements. Furthermore, a total of forty PEBP genes from C. sinense, C. ensifolium, C. goeringii, Phalaenopsis, and Arabidopsis were divided into three clades based on the phylogenetic tree. The expression patterns of 11 PEBP genes in different tissues and organs of C. ensifolium were analyzed based on transcriptome data, indicating that the CePEBPs might play an important role in the growth and development, especially in the flower bud organs (1-5 mm). CePEBP5 plays an indispensable role in both the vegetative and reproductive growth cycles of C. ensifolium. CePEBP1 is essential for root development, while CePEBP1, CePEBP3, CePEBP5, and CePEBP10 regulate the growth and development of different floral organ tissues at various stages. The findings of this study can do a great deal to understand the roles of the PEBP gene family in Cymbidium.