The MYB transcription factor RcMYB1 plays a central role in rose anthocyanin biosynthesis

Abstract

Rose (Rosa hybrida) is one of most famous ornamental plants in the world, and its commodity value largely depends on its flower color. However, the regulatory mechanism underlying rose flower color is still unclear. In this study, we found that a key R2R3-MYB transcription factor, RcMYB1, plays a central role in rose anthocyanin biosynthesis. Overexpression of RcMYB1 significantly promoted anthocyanin accumulation in both white rose petals and tobacco leaves. In 35S: RcMYB1 transgenic lines, a significant accumulation of anthocyanins occurred in leaves and petioles. We further identified two MBW complexes (RcMYB1-RcBHLH42-RcTTG1; RcMYB1-RcEGL1-RcTTG1) associated with anthocyanin accumulation. Yeast one-hybrid and luciferase assays showed that RcMYB1 could active its own gene promoter and those of other EBGs (early anthocyanin biosynthesis genes) and LBGs (late anthocyanin biosynthesis genes). In addition, both of the MBW complexes enhanced the transcriptional activity of RcMYB1 and LBGs. Interestingly, our results also indicate that RcMYB1 is involved in the metabolic regulation of carotenoids and volatile aroma. In summary, we found that RcMYB1 widely participates in the transcriptional regulation of ABGs (anthocyanin biosynthesis genes), indicative of its central role in the regulation of anthocyanin accumulation in rose. Our results provide a theoretical basis for the further improvement of the flower color trait in rose by breeding or genetic modification.

Acknowledgements

We acknowledge Wenqiu Wang (College of Agriculture and Biotechnology, Zhejiang University, China) for the technical assistance. We thank Jennifer Smith, PhD, from Liwen Bianji (Edanz) (www.liwenbianji.cn/) for editing the English text of a draft of this manuscript. This work was supported by Shanghai Special Project of Capacity Construction for Local Colleges and Universities, No.20070502500; Shanghai Science and Technology Agriculture Program, No.2022-02-08-00-12-F01146; Science and Technology Commission of Shanghai Municipality, No.18DZ2260500; and Shanghai Plant Germplasm Resources Engineering Research Center, 17DZ2252700.

Author contributions

F.M. designed the research and is the author responsible for distribution of materials integral to the findings presented in this article in accordance with the policy described in the Instructions for Authors. G.H., R.Z., S.J., and H.W. conducted the experiments. G.H. and R.Z. analysed the data and wrote the manuscript. All authors read and approved the manuscript.

Data availability

All relevant data in this study are provided in the article and its supplementary file.

Conflict of interest

The authors declare that they have no conflict of interest.

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