Key genes for phenylpropanoid metabolite biosynthesis during half-highbush blueberry (Vaccinium angustifolium×Vaccinium corymbosum) fruit development

Abstract

BACKGROUND: Blueberry fruits contain large amounts of phenolic compounds derived from the phenylpropanoid pathway. Their biosynthesis is complex, involving many enzymes. OBJECTIVE: We sought to investigate the content of phenylpropanoid-derived compounds and identify key genes involved in the phenylpropanoid metabolite pathway during half-highbush blueberry fruit development. METHODS: Phenylpropanoid metabolite contents were determined by high-performance liquid chromatography (HPLC) and spectrophotometry. Gene expression was examined through reverse-transcription PCR. RESULTS: Phloretin, chlorogenic acid, total flavonol, quercetin, catechin, and proanthocyanidin contents were highest in small-sized green fruits; myricetin and epicatechin contents were highest in pink fruits; and lignin and anthocyanin were highest in blue fruits. Genes from the 4-coumarate CoA ligase (4CL) family regulate the biosynthesis of phenylpropanoid metabolites. Phenylalanine ammonia-lyase (PAL) and cinnamoyl-CoA reductase (CCR) are key genes in the lignin biosynthetic pathway. Flavonol synthase (FLS) is a key gene affecting total flavonols and the quercetin biosynthetic pathway. PAL and chalcone isomerase (CHI) are key genes in the epicatechin and anthocyanin biosynthetic pathways, respectively. CONCLUSION: Phenylpropanoid metabolites are regulated by multiple genes from the same or different families. Enzymes in different metabolic pathways compete for precursors to form a complex regulatory network for phenylalanine metabolism.

Gene expression controlling signalling molecules within mutualistic associations of an invasive plant: An evolutionary perspective

“…FLS encodes a key enzyme that catalyses the last steps in the formation of quercetin from phenylalanine (Li et al, 2020;Yang et al, 2022). In our study, we confirmed the expression levels of FLS by transcriptomics and fluorescent real-time quantitative PCR (qPCR), which showed that both quercetin and myricetin (which is synthesized from quercetin) metabolism were positively related to the expression of FLS (Figure 4c), and there were higher concentrations of myricetin and quercetin as well as higher expression of FLS in invasive populations of T. sebifera (Figure 4a,b).…”

Molecular profiling of chemical signals enhancing plant invasion by shaping mutualistic associations

“…Quercetin is a ubiquitous flavonoid in plants and the predominant flavanol in leaves of T. sebifera (Wang et al 2012;Tian et al 2021). FLS encodes a key enzyme that catalyzes the last steps in the formation of quercetin from phenylalanine (Li et al 2020;Yang et al 2022). In our study, we confirmed the expression levels of FLS by transcriptomics and fluorescent real-time quantitative PCR (qPCR), which showed that both quercetin and myricetin (which is synthesized from quercetin) metabolism were positively related to the expression of FLS (Figure 4c), and there were higher concentrations of myricetin and quercetin as well as higher expression of FLS in invasive populations of T. sebifera (Figure 4a, b).…”

“…Metabolite biosynthesis is largely regulated at the transcriptional level due to modified expression levels of genes (Yang et al 2022). However, the mechanistic basis of enhanced mutualism from evolved changes in gene expression is still not understood.…”

UV-B induces the expression of flavonoid biosynthetic pathways in blueberry (Vaccinium corymbosum) calli

“…WGCNA has been widely used to identify gene regulatory networks from different KEGG pathways ( Zhu et al., 2019 ; Li et al., 2022 ). The biosynthesis of flavonoid compounds is co-regulated by multiple genes (e.g., PAL , 4CL , CHI , and FLS ) during half-high blueberry fruit development ( Yang et al., 2022b ). In the current study, we assembled the regulatory network of the phenylpropanoid biosynthesis pathway under UV radiation using WGCNA.…”