Genome-Wide Identification, Characterization, and Expression Analysis of the <i>U-Box</i> Gene Family in <i>Punica granatum</i> L.

The ubiquitination pathway is essential for several developmental phases in plants, and the U-box protein family of ubiquitin ligases plays an important role in this process. However, little is known about pomegranate’s PUB genes. In this investigation, the pomegranate U-box gene family was identified using whole-genome sequencing data. We identified a total of 56 members of the pomegranate U-box family based on the U-box domain, and the PgPUBs were classified into four groups. Chromosomal localization, phylogenetic analysis, motif distribution, gene duplications, cis-acting elements, and expression profiling were also investigated. The PgPUB genes were unevenly distributed among the eight pomegranate chromosomes, and collinear duplicated genes were identified between the Arabidopsis thaliana genome and the Punica granatum genome. Furthermore, the gene expression analysis revealed that expression of U-box genes in pomegranate was induced by abiotic stressors. Collectively, our findings provide insight into the U-box gene family and will assist in understanding the functional divergence of U-box genes in Punica granatum L