Comprehensive analysis of sweet cherry UDP-glycosyltransferases and functional validation of PavUGT10 for improving...

Sweet cherry (Prunus avium L.) is an economically significant fruit crop, and improving its resilience to abiotic stress is crucial for sustainable production and industrial value. UDP-glycosyltransferases (UGTs) modulate hormone homeostasis, secondary metabolism, and stress responses in plants, yet their roles in sweet cherry remain largely uncharacterized. Here, we report a comprehensive genome-wide analysis of the PavUGT family, identifying 235 genes unevenly distributed across eight chromosomes and classified into 18 phylogenetic subfamilies. Promoter analysis revealed enrichment of stress-responsive cis-elements, and comparative synteny with multiple dicots including Arabidopsis, strawberry, apple, peach, and pear highlighted both conserved genomic blocks and lineage-specific expansions. Transcriptome profiling under waterlogging stress revealed a large set of PavUGTs with significant induction; twelve representative genes were selected for RT-qPCR validation, and PavUGT10 was further characterized functionally. Subcellular localization of PavUGT10-GFP in Nicotiana leaves confirmed nuclear localization, consistent with predictions. Overexpression (OE) lines of PavUGT10 in Arabidopsis significantly enhanced tolerance to 60 h of dark submergence followed by fifteen days of recovery; OE3 and OE7 achieved survival rates of 70 % and 75 %, respectively, compared to 25 % in WT. This enhanced tolerance was associated with elevated antioxidant enzyme activities (SOD, POD, CAT), increased proline accumulation, reduced MDA content, and reduced ROS accumulation, collectively indicating improved ROS scavenging and stress adaptation. These findings establish the PavUGT gene family as key players in cherry rootstocks' adaptive responses to waterlogging and identify PavUGT10 as a promising candidate for molecular breeding of flood-tolerant cultivars.