Wang Jiafa, Li Guobin, Li Changxing, Zhang Chunli, Cui Long, Ai Guo, Wang Xin, Zheng Fangyan, Zhang Dedi, Larkin Robert M, Ye Zhibiao, Zhang Junhong
The Key Laboratory of Horticultural Plant Biology, Ministry of Education, Huazhong Agricultural University, Wuhan, 430070, China.
New Phytol. 2021 Mar;229(6):3237-3252. doi: 10.1111/nph.17112. Epub 2020 Dec 21.
NF-Y transcription factors are reported to play diverse roles in a wide range of biological processes in plants. However, only a few active NF-Y complexes are known in plants and the precise functions of NF-Y complexes in flavonoid biosynthesis have not been determined. Using various molecular, genetic and biochemical approaches, we found that NF-YB8a, NF-YB8b and NF-YB8c - a NF-YB subgroup - can interact with a specific subgroup of NF-YC and then recruit either of two distinct NF-YAs to form NF-Y complexes that bind the CCAAT element in the CHS1 promoter. Furthermore, suppressing the expression of particular NF-YB genes increased the levels of H3K27me3 at the CHS1 locus and significantly suppressed the expression of CHS1 during tomato fruit ripening, which led to the development of pink-coloured fruit with colourless peels. Altogether, by demonstrating that NF-Y transcription factors play essential roles in flavonoid biosynthesis and by providing significant molecular insight into the regulatory mechanisms that drive the development of pink-coloured tomato fruit, we provide a major advance to our fundamental knowledge and information that has considerable practical value for horticulture.
据报道，NF-Y转录因子在植物的广泛生物过程中发挥着多种作用。然而，植物中已知的活性NF-Y复合物很少，并且NF-Y复合物在类黄酮生物合成中的精确功能尚未确定。通过各种分子、遗传和生化方法，我们发现NF-YB8a、NF-YB8b和NF-YB8c（一个NF-YB亚组）可以与特定的NF-YC亚组相互作用，然后招募两种不同的NF-YA中的任何一种来形成结合CHS1启动子中CCAAT元件的NF-Y复合物。此外，抑制特定NF-YB基因的表达会增加CHS1基因座处H3K27me3的水平，并在番茄果实成熟过程中显著抑制CHS1的表达，这导致了果皮无色的粉红色果实的发育。总之，通过证明NF-Y转录因子在类黄酮生物合成中起重要作用，并通过对驱动粉红色番茄果实发育的调控机制提供重要的分子见解，我们为基础知识和信息提供了重大进展，这些知识和信息对园艺具有相当大的实用价值。
