Resumen de Tissue-specific accummulation of flavonoids in grape berries is related to transcriptional expression of VvF3'H and VvF3'5'H
L. Mu, J.-J. He, Qiu-Hong Pan, F. He, Chang-Qing Duan
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.
