1. The R2R3 MYB Ruby1 is activated by two cold responsive ethylene response factors, via the retrotransposon in its promoter, to positively regulate anthocyanin biosynthesis in citrus.
- Author
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Wang Y, Li S, Shi Y, Lv S, Zhu C, Xu C, Zhang B, Allan AC, Grierson D, and Chen K
- Subjects
- Ethylenes metabolism, Ethylenes biosynthesis, Cold Temperature, Citrus genetics, Citrus metabolism, Anthocyanins biosynthesis, Anthocyanins metabolism, Plant Proteins genetics, Plant Proteins metabolism, Gene Expression Regulation, Plant, Promoter Regions, Genetic, Transcription Factors metabolism, Transcription Factors genetics, Retroelements genetics
- Abstract
Anthocyanins are natural pigments and dietary antioxidants that play multiple biological roles in plants and are important in animal and human nutrition. Low temperature (LT) promotes anthocyanin biosynthesis in many species including blood orange. A retrotransposon in the promoter of Ruby1, which encodes an R2R3 MYB transcription factor, controls cold-induced anthocyanin accumulation in blood orange flesh. However, the specific mechanism remains unclear. In this study, we characterized two LT-induced ETHYLENE RESPONSE FACTORS (CsERF054 and CsERF061). Both CsERF054 and CsERF061 can activate the expression of CsRuby1 by directly binding to a DRE/CRT cis-element within the retrotransposon in the promoter of CsRuby1, thereby positively regulating anthocyanin biosynthesis. Further investigation indicated that CsERF061 also forms a protein complex with CsRuby1 to co-activate the expression of anthocyanin biosynthetic genes, providing a dual mechanism for the upregulation of the anthocyanin pathway. These results provide insights into how LT mediates anthocyanin biosynthesis and increase the understanding of the regulatory network of anthocyanin biosynthesis in blood orange., (© 2024 The Author(s). The Plant Journal published by Society for Experimental Biology and John Wiley & Sons Ltd.)
- Published
- 2024
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