A MYB-INDUCED MECHANISM FOR ENHANCED ASCORBATE IN RED-FLESHED APPLES

Abstract

The results presented in “The anthocyanin biosynthetic regulator MdMYB1 positively regulates ascorbic acid biosynthesis in apple” (An et al., this issue) provide evidence for a new mechanism for the elevation of ascorbate concentration in apple. Using a red-fleshed apple breeding population, the authors show how the anthocyanin-regulating MYB transcription factor, MdMYB1, also increases ascorbate concentrations by directly activating transcription of the dehydroascorbate reductase gene MdDHAR. This gene recycles oxidized ascorbate back to ascorbate, leading to elevated concentrations of vitamin C. These red-fleshed apples have enhanced concentrations of both anthocyanins and ascorbate, both of which are appealing traits for the development of healthier apples.

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RIGHTS & PERMISSIONS

The Author(s) 2021. Published by Higher Education Press. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0)