Proteome analysis provides new insight into major proteins involved in gibberellin-induced fruit setting in triploid loquat ( Eriobotrya japonica )

Background Parthenocarpy can be induced by gibberellin (GA) treatment in plants. The fruits of the loquat exhibit many seeds. GA treatment can induce the development of seedless fruit and increase fruit quality during production. However, the molecular mechanism of fruit setting under GA treatment is still unclear. Objective Our aim was to explore GA-induced parthenocarpy in triploid loquat by proteome analysis to identify the differentially expressed proteins. Methods A proteome analysis was performed using TMT protein labeling and LC-MS/MS in triploid loquat. Results A total of 7290 protein groups were identified in the two stages of fruit setting. The quantitative results showed that 923 differentially expressed proteins (DEPs) were isolated, which were enriched in five pathways: ribosome, citrate cycle (TCA cycle), pentose phosphate, carbon metabolism, and carbon fixation. Twenty-four DEPs were annotated as putative key regulatory proteins involved in fruit setting, which were related to the auxin response, gibberellin metabolism, ethylene synthesis, and cell division. In addition, thirty-five DEPs were involved in the formation of the cell wall, which might be downstream proteins involved in cell proliferation during fruit setting. Conclusion Our report reveals new insight into the protein dynamics of loquat fruit setting induced by GA treatment via the analysis of proteome profiles and provides a reference for other Rosaceae species.