AUTHOR=Zhang Ya-Ling , Lin-Wang Kui , Albert Nick W. , Elborough Caitlin , Espley Richard V. , Andre Christelle M. , Fang Zhi-Zhen 

TITLE=Identification of a Strong Anthocyanin Activator, VbMYBA, From Berries of Vaccinium bracteatum Thunb.

JOURNAL=Frontiers in Plant Science

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2021.697212

DOI=10.3389/fpls.2021.697212

ISSN=1664-462X

ABSTRACT=<p>Wufanshu (<italic>Vaccinium bracteatum</italic> Thunb.), which is a wild member of the genus <italic>Vaccinium</italic>, accumulates high concentration of anthocyanin in its berries. In this study, the accumulated anthocyanins and their derivatives in Wufanshu berries were identified through UHPLC–MS/MS analysis. Candidate anthocyanin biosynthetic genes were identified from the transcriptome of Wufanshu berries. qRT-PCR analyses showed that the expression of anthocyanin structural genes correlated with anthocyanin accumulation in berries. The R2R3-MYB, <italic>VbMYBA</italic>, which is a homolog of anthocyanin promoting R2R3-MYBs from other <italic>Vaccinium</italic> species, was also identified. Transient expression of <italic>VbMYBA</italic> in <italic>Nicotiana tabacum</italic> leaves confirmed its role as an anthocyanin regulator, and produced a higher anthocyanin concentration when compared with blueberry <italic>VcMYBA</italic> expression. Dual-luciferase assays further showed that VbMYBA can activate the <italic>DFR</italic> and <italic>UFGT</italic> promoters from other <italic>Vaccinium</italic> species. VbMYBA has an additional 23 aa at the N terminus compared with blueberry VcMYBA, but this was shown not to affect the ability to regulate anthocyanins. Taken together, our results provide important information on the molecular mechanisms responsible for the high anthocyanin content in Wufanshu berries.</p>