CsMYB184 regulates caffeine biosynthesis in tea plants

作者：Penghui Li, Zhili Ye, Jiamin Fu, Yujie Xu, Yihua Shen, Yanrui Zhang, Dingkun Tang, Ping Li, Hao Zuo, Wei Tong, Shucai Wang, Alisdair R. Fernie, Jian Zhao · 发表于：Plant Biotechnology Journal · 年份：2022 · DOI：10.1111/pbi.13814 · 被引用次数：51 · 研究领域：Coffee research and impacts、Tea Polyphenols and Effects、Sirtuins and Resveratrol in Medicine

As the most well-known and globally consumed central nervous system stimulant, caffeine is a purine alkaloid natural product usually derived from tea and coffee. Caffeine has a wide range of health benefits on the human body, and plays crucial roles in pollination, resistance to herbivore attacks, and pathogen infections in plants (Zhao et al., 2020). While caffeine biosynthetic pathways have been extensively studied in tea (Camellia sinensis L) and coffee plants, the regulation of caffeine biosynthesis is not understood (Zhao et al., 2020). Tea Caffeine Synthase1 (TCS1) is the first N-methyltransferase gene reported in the tea plant, possessing the 1-N methyltransferase activity responsible for converting theobromine to caffeine (Kato et al., 2000). Studies on the structure–activity of TCS1 and genetic variations in the TCS1 gene of tea plant populations have supported that TCS1 is a determination enzyme for caffeine content (Jin et al., 2016). To explore the regulation of caffeine biosynthesis, 23 candidate transcription factors (TFs) from Weighted Gene Co-expression Network Analysis were screened in a luciferase reporter gene activation system driven by the TCS1 promoter (Figure S1). MYB184 (TEA029017) showed the highest TCS1 promoter activation with 4.7-fold (Figure 1a). Yeast one-hybrid assay showed that the −828 to −1670 bp region of TCS1 promoter, which contains an MYBCORE and a fused MYB1AT-MYBPLANT, was critically required for MYB184 recognition (Figure 1b). In plant...