[Analysis of flavonoid accumulation and expression patterns of F3H and F3'H genes during fruit development in...

To elucidate the biosynthesis mechanism of flavonoids at different developmental stages of Gardenia jasminoides fruit and identify key regulatory genes, this study used the pericarp and sarcocarp of green and red fruit as the materials. Non-targeted metabolomics analysis based on ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-ESI-MS/MS) was performed, followed by integrated transcriptomic data mining to screen candidate genes involved in flavonoid biosynthesis. The expression patterns of these genes were subsequently validated by real-time quantitative PCR(RT-qPCR). The results showed that flavonoids accumulate significantly in the pulp of G.jasminoides fruits, with flavonol components being particularly prominent in the red pulp. Integrated metabolomic and transcriptomic analysis suggested that apigenin is a key precursor, while flavanone 3-hydroxylase(F3H) and flavonoid 3'-hydroxylase(F3'H) are key rate-limiting enzymes regulating hydroxylation modifications of flavonoids. Phylogenetic and expression analyses further revealed that members of the GjF3'H family exhibit distinct evolutionary specificity and tissue-specific expression patterns. This study provides a multi-omics perspective on the accumulation patterns and key biosynthetic genes of flavonoids in G. jasminoides fruit, thereby offering a theoretical basis for the targeted breeding and quality control of flavonoid components in G. jasminoides.