Integrative analysis of the transcriptome and metabolome reveals the peel coloration mechanism of Zanthoxylum armatum
摘要
Zanthoxylum armatum is a globally recognized medicinal and edible plant, the fruit peel color of which is considered an important trait that influences its economic value. In this study, Z. armatum fruits were used at five different stages of development to explore the law of metabolite biosynthesis and its potential molecular mechanism.
ResultsUsing transcriptomic and widely-targeted metabolomic analyses, 23 differentially accumulated metabolites, 274 differentially expressed structural genes, and 230 differentially expressed transcription factor genes associated with anthocyanin synthesis were identified. Based on co-expression network analysis, key structural genes positively associated with anthocyanin biosynthesis were identified and the corresponding hub transcription factor genes were predicted. Cyanidin-3-O-arabinoside, cyanidin-3-O-glucoside, cyanidin-3-O-(2ʹʹ-O-glucosyl)glucoside, cyanidin-3-O-(6’’-O-malonyl)glucoside, cyanidin-3-O-rutinoside, cyanidin-3-O-galactoside, and petunidin-3-O-glucoside-5-O-arabinoside were identified as key anthocyanins accumulated in the peel of mature Z. armatum fruits, the synthesis of which appeared to involve the structural genes PAL5, PAL8, PAL9, PAL11, PAL13, PAL14, C4H2, CHS17, F3’H2, DFR1, ANS2, and ANS4 as candidate catalysts. Furthermore, dual-luciferase reporter assays indicated that bHLH-MYC9 and MYB19 may trans-activate the promoters of ANS2 and ANS4, respectively.
ConclusionsOur findings in this study provide new perspectives regarding the regulation of peel color development during the ripening of Z. armatum fruit.