Molecular characterization of flavanone 3-hydroxylase gene and flavonoid accumulation in two chemotyped safflower lines in response to methyl jasmonate stimulation

Abstract

BackgroundAmong secondary metabolites, flavonoids are particularly crucial for plant growth, development, and reproduction, as well as beneficial for maintenance of human health. As a flowering plant, safflower has synthesized a striking variety of flavonoids with various pharmacologic properties. However, far less research has been carried out on the genes involved in the biosynthetic pathways that generate these amazing flavonoids, especially characterized quinochalcones. In this study, we first cloned and investigated the participation of a presumed flavanone 3-hydroxylase gene (F3H) from safflower (CtF3H) in a flavonoid biosynthetic pathway.ResultsBioinformation analysis showed that CtF3H shared high conserved residues and confidence with F3H from other plants. Subcellular localization uncovered the nuclear and cytosol localization of CtF3H in onion epidermal cells. The functional expressions of CtF3H in Escherichia coli BL21(DE3)pLysS cells in the pMAL-C5x vector led to the production of dihydrokaempferol when naringenin was the substrate. Furthermore, the transcriptome expression of CtF3H showed a diametrically opposed expression pattern in a quinochalcone-type safflower line (with orange-yellow flowers) and a flavonol-type safflower line (with white flowers) under external stimulation by methyl jasmonate (MeJA), which has been identified as an elicitor of flavonoid metabolites. Further metabolite analysis showed the increasing tendency of quinochalcones and flavonols, such as hydroxysafflor yellow A, kaempferol-3-O-β-D-glucoside, kaempferol-3-O-β-rutinoside, rutin, carthamin, and luteolin, in the quinochalcone-type safflower line. Also, the accumulation of kaempferol-3-O-β-rutinoside and kaempferol-3-O-β-D-glucoside in flavonols-typed safflower line showed enhanced accumulation pattern after MeJA treatment. However, other flavonols, such as kaempferol, dihydrokaempferol and quercetin-3-O-β-D-glucoside, in flavonols-typed safflower line presented down accumulation respond to MeJA stimulus.ConclusionsOur results showed that the high expression of CtF3H in quinochalcone-type safflower line was associated with the accumulation of both quinochalcones and flavonols, whereas its low expression did not affect the increased accumulation of glycosylated derivatives (kaempferol-3-O-β-rutinoside and rutin) in flavonols-typed safflower line but affect the upstream precursors (D-phenylalanine, dihydrokaempferol, kaempferol), which partly revealed the function of CtF3H in different phenotypes and chemotypes of safflower lines.Electronic supplementary materialThe online version of this article (doi:10.1186/s12870-016-0813-5) contains supplementary material, which is available to authorized users.

Genome-wide interologous interactome map (TeaGPIN) of Camellia sinensis

“…Protein TEA023790.1 with 55 interactions and KO id K00475 codes for F3H enzyme (Flavanone 3-hydroxylase). F3H is a known nuclear enzyme important for flavonoid biosynthetic pathway by catalysis of 3-hydroxylation of (2S)-flavanones that includes naringenin to dihydroflavonols [76]. Protein TEA032730.1 with 50 interactions has function of bifunctional dihydroflavonol 4-reductase (DFR) that is an oxidoreductase and produces flavan 3,4-diols by catalysing the NADPH dependent reduction of keto group at the 4 th position of dihydroflavonols.…”

Tissue-specific transcriptional biomarkers in medicinal plants: Application of large-scale meta-analysis and computational systems biology

“…The majority of F3H genes have been obtained from some herbal medicines, including Ginkgo biloba (Shen et al, 2006), Carthamus tinctorius (Tu et al, 2016) and Camellia sinensis (Singh et al, 2008). The genes expression of CHS and F3H is influenced in response to environmental stress and exposure to JA which increased accumulation of flavonoid (Dao et al, 2011;Tu et al, 2016). Cytochrome P450 reductase belongs to the cytochrome P450 superfamily (CYP) that catalyzes 3hydroxylation of p-coumaroyl shikimate to monolignol lignin precursor.…”

A Brief Review on Secondary Metabolites Biosynthesis Regulation: Application in Gynura Procumbens in Glasshouse Condition

“…To date, elicitor and precursor have been widely used to increase the production as well as to induce de novo synthesis of secondary metabolites by means of in vitro plant cell cultures (Tu et al, 2016). However, glasshouse condition seems to work best for domesticating the study of abiotic influence on secondary metabolites production since the agricultural cultivation and natural habitat have shown similar responses to manipulations (Massad, Fincher, Smilanich, & Dyer, 2011).…”