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bioRxiv · 10.1101/139105

Isolation And Characterization Of Key Genes That Promote Flavonoid Accumulation In Purple-Leaf Tea (Camellia sinensis L.)

Abstract

There were several high concentrations of flavonoid components in tea leaves that present health benefits. A novel purple-leaf tea variety, Mooma1, was obtained from the natural hybrid population of Longjing 43 variety. The buds and young leaves of Mooma1 were displayed in bright red. HPLC and LC-MS analysis showed that anthocyanins and O-Glycosylated flavonols were remarkably accumulated in the leaves of Mooma1, while the total amount of catechins in purple-leaf leaves was slightly decreased compared with the control. A R2R3-MYB transcription factor (CsMYB6A) and a novel UGT gene (CsUGT72AM1), that were highly expressed in purple leaf were isolated and identified by transcriptome sequencing. The over-expression of transgenic tobacco confirmed that CsMYB6A can activate the expression of flavonoid-related structural genes, especially CHS and 3GT, controlling the accumulation of anthocyanins in the leaf of transgenic tobacco. Enzymatic assays in vitro confirmed that CsUGT72AM1 has catalytic activity as a flavonol 3-O-glucosyltransferase, and displayed broad substrate specificity. The results were useful for further elucidating the molecular mechanisms of the flavonoid metabolic fluxes in the tea plant.

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BibTeXRIS

He, X., Zhao, X., Gao, L., Shi, X., Dai, X., Liu, Y., Xia, T., Wang, Y.. 2017-05-17. Isolation And Characterization Of Key Genes That Promote Flavonoid Accumulation In Purple-Leaf Tea (Camellia sinensis L.). https://doi.org/10.1101/139105

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