Integration of transcriptomic and metabolomic profiling unveil the mechanisms in ‘Kongxin’ plum (Prunus salicina L.) peel reddening during storage

Abstract

The fundamental mechanisms causing the peel reddening of ‘Kongxin’ plum (Prunus salicina Lindl.) fruit maintained at room temperature at 25 °C were discovered through an integrated analysis of the transcriptomics and metabolomics. There were apparent differences in fruit quality among the three periods. We also performed transcriptomic and metabolomic analyses of plum fruit peel at different reddening stages and identified 495 secondary metabolites in ‘Kongxin’ plums during reddening. The primary coloring agents in plum peel were anthocyanins, and a significant buildup of cyanidin-3-O-glucoside was what gives plum peel its reddening. Moreover, structural genes linked to anthocyanin production of PAL1, C4H, CHS1, and DFR2, which may be the primary players increased during the process of plum peel reddening. In the plum peel, PsMYB75, PsbHLH62 and PsWRKY71 strongly and favorably associated with anthocyanin accumulation and served as a positive regulator of the accumulation of anthocyanin. These findings offer fresh insights into the molecular mechanisms underlying the red change of anthocyanin production in ‘Kongxin’ plum peel.