Transcriptional regulation of flavonol biosynthesis in plants

Abstract

Flavonols are a class of flavonoids that play a crucial role in regulating plant growth and promoting stress resistance. They are also important dietary components in horticultural crops due to their benefits for human health. In past decades, research on the transcriptional regulation of flavonol biosynthesis in plants has increased rapidly. This review summarizes recent progress in flavonol-specific transcriptional regulation in plants, encompassing characterization of different categories of transcription factors (TFs) and microRNAs as well as elucidation of different transcriptional mechanisms, including direct and cascade transcriptional regulation. Direct transcriptional regulation involves TFs, such as MYB, AP2/ERF, and WRKY, which can directly target the key flavonol synthase gene or other early genes in flavonoid biosynthesis. In addition, different regulation modules in cascade transcriptional regulation involve microRNAs targeting TFs, regulation between activators, interaction between activators and repressors, and degradation of activators or repressors induced by UV-B light or plant hormones. Such sophisticated regulation of the flavonol biosynthetic pathway in response to UV-B radiation or hormones may allow plants to fine-tune flavonol homeostasis, thereby balancing plant growth and stress responses in a timely manner. Based on orchestrated regulation, molecular design strategies will be applied to breed horticultural crops with excellent health-promoting effects and high resistance.

Acknowledgements

This work was supported by the National Natural Science Foundation of China (32372667), the Natural Science Foundation of Shandong Province (ZR2023QC228), the Key Research and Development Program of Zhejiang Province (2021C02001), and the Key Project for New Variety Breeding in Agriculture of Zhejiang Province (2021C02066-3).

Author contributions

Y.C. and X.L. designed this review. Y.C., Y.M., R.Z., and Z.Z. conducted the literature review and wrote the manuscript. K.C., C.X., and X.L. carefully compiled and revised the paper. X.Y. provided discussion and comments on the paper. All authors approved the final submission.

Data availability

The authors confirm that all data in this study are available and can be found in this article.

Conflict of interest

The authors declare that they have no conflict of interest.

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