Genome-Wide Identification and Characterization of WRKY Transcription Factors and Their Expression Profile in var. .

The gene family plays important roles in plant growth and development, as well as in the responses to biotic and abiotic stresses. var. has high ornamental and medicinal value. However, few genes have been reported in this plant, and their functions remain unknown. To explore the roles that the genes play in var. , we identified and characterized 79 through BLAST homology analysis and renamed them (as ) based on their distribution on the chromosomes of var. . In this way, according to their structural characteristics and phylogenetic analysis, they were divided into three groups containing 16 (Group I), 52 (Group II), and 11 (Group III) WRKYs, respectively. LcWRKYs in the same group have similar motifs and gene structures; for instance, Motifs 1, 2, 3, 4, and 10 constitute the WRKY domain and zinc-finger structure. The promoter region contains light response elements (ACE, G-box), stress response elements (TC-rich repeats), hormone response elements (TATC-box, TCA-element), and MYB binding sites (MBS, MBSI). Synteny analysis of allowed us to establish orthologous relationships among the gene families of , , L., L., L., and L.; furthermore, analysis of the transcriptomes of mature leaves and flowers from different cultivars demonstrated the cultivar-specific gene expression. The expression levels of certain genes also presented responsive changes from young to mature leaves, based on an analysis of the transcriptome in leaves at different developmental stages. White light treatment led to a significant decrease in the expression of and and a significant increase in the expression of , blue light treatment led to a significant decrease in the expression of and and a significant increase in the expression of and . These results enable a better understanding of , facilitating the further exploration of their genetic functions and the molecular breeding of var. .