Unveiling kiwifruit TCP genes: evolution, functions, and expression insights.

The (TCP) gene family is a plant-specific transcriptional factor family involved in leaf morphogenesis and senescence, lateral branching, hormone crosstalk, and stress responses. To date, a systematic study on the identification and characterization of the gene family in kiwifruit has not been reported. Additionally, the function of kiwifruit TCPs in regulating kiwifruit responses to the ethylene treatment and bacterial canker disease pathogen ( pv. , Psa) has not been investigated. Here, we identified 40 and 26 genes in (Ac) and (Ae) genomes, respectively. The synteny analysis of illustrated that whole-genome duplication accounted for the expansion of the family in Ac. Phylogenetic, conserved domain, and selection pressure analysis indicated that family genes in Ac and Ae had undergone different evolutionary patterns after whole-genome duplication (WGD) events, causing differences in gene number and distribution. Our results also suggested that protein structure and -element architecture in promoter regions of TCP genes have driven the function divergence of duplicated gene pairs. Three and four genes significantly affected kiwifruit responses to the ethylene treatment and Psa invasion, respectively. Our results provided insight into general characters, evolutionary patterns, and functional diversity of kiwifruit .