Tissue-specific Accumulation of Flavonoids in Grape Berries is Related to Transcriptional Expression of VvF3′H and VvF3′5′H

Abstract

The products and the related gene expression of flavonoid metabolism were examined in the skin and pulp of Yan73 (Vitis vinifera L. cv.) grapes, a teinturier variety cultivated in China, and the data were compared with those in the skin and pulp of Cabernet Sauvignon (Vitis vinifera L. cv.) grapes, a well-known red variety. The results showed that, in comparison with the skins of Cabernet Sauvignon, the skins of Yan73 berries were characterised by fewer types of flavonols and anthocyanins, a higher level of flavonoids, and a much lower percentage of 3′-hydroxylated flavonols. Flavonoid metabolism was also present in the pulp of Yan73, and the percentages of 3′-hydroxylated flavonols and 3′-hydroxylated flavan-3-ols were significantly higher than the percentages of their corresponding 3′,5′-hydroxylated forms. Only flavan-3-ols were found in the pulp of Cabernet Sauvignon. The expression of VvmybA1 exhibited a co-ordination with the accumulation of anthocyanins in the pulp of the teinturier cultivar, which showed great similarity to that in the skin. A good correlation was found between the expression of VvF3′H and 3′-hydroxylated flavonoids, as well as between the expression of VvF3′5′H and 3′,5′-hydroxylated flavonoids in the skin and pulp of the grape berries. It is suggested that tissue-specific accumulation of flavonoids in grape berries is related to the transcriptional expression of VvF3′H and VvF3′5′H.

Color Intensity of the Red-Fleshed Berry Phenotype of Vitis vinifera Teinturier Grapes Varies Due to a 408 bp Duplication in the Promoter of VvmybA1

“…The two key enzymes flavonoid 3’-hydroxylase (F3’H) and flavonoid 3’,5’-hydroxylase (F3′5′H) use the flavanone naringenin as the main substrate for a hydroxylation reaction. The resulting amounts of 3′-hydroxylated flavonoids and 3′,5′-hydroxylated flavonoids correlate with the expression level of the F3′H and F3′5′H , respectively [ 9 , 10 ]. All precursors of the anthocyanins are colorless up to a final glycosylation by UFGT (UDP-glucose: flavonoid-3- O -glucosyltransferase) resulting in the color-intensive pigments [ 11 ].…”

A wild ‘albino’ bilberry (Vaccinium myrtillus L.) from Slovenia shows three bottlenecks in the anthocyanin pathway and significant differences in the expression of several regulatory genes compared to the common blue berry type

“…In addition, we measured the specific activities of selected enzymes and concentrations of primary and secondary metabolites. We particularly focused on the polyphenol metabolism in berry skins, since previous studies have indicated that some key genes that are related to anthocyanin accumulation are expressed mainly in the skin [ 29 , 30 ].…”

Transcriptomic analysis of berry development and a corresponding analysis of anthocyanin biosynthesis in teinturier grape

“…Thus, F3'H and F3'5'H could divide and separate the flavonoid pathway into two branches that lead to the accumulation of cyanidin-; peonidin-glycosides (red to purple) and delphinidin-; malvidin-; petunidin-glycosides (blue to purple), respectively. A previous study (Mu et al 2014) on a teinturier cultivar, 'Yan-73,' demonstrated that the transcript level of F3'H was much higher than F3'5'H in pulp tissue. In our study, however, the expression level of F3'5'H was significantly higher than F3'H.…”