Genome-Wide Identification and Characterization of the / Gene Family in Strawberry Species.

Auxin is the first plant hormone found to play a dominant role in fruit growth, from fruit set to fruit ripening. Strawberry plants represent a suitable model for studying auxin's biosynthesis, sensing, and signaling machinery. / genes are a classical rapid auxin-responsive family. However, the / gene family in genus is poorly understood. In this study, a total of 287 / genes were identified in the eight strawberry genomes. Their physicochemical properties, domain structure, and cis-regulatory elements revealed the functional multiplicity of the strawberry /s. We used a phylogenetic analysis to classify these genes into 12 classes. In addition, based on synteny analysis, gene duplications, and calculation of the Ka/Ks ratio, we found that segmental duplications promote the evolution of /s in species, which is followed by purifying selection. Furthermore, the expression pattern and protein-protein interaction network of these genes in revealed various tissue-specific expressions and probable regulatory functions. Taken together, these results provide basic genomic information and a functional analysis of these genes, which will serve to expand our understanding of the direction in which the / gene family is evolving in species.