Browse Articles

Article|17 Nov 2023|OPEN
CsMYB67 participates in the flavonoid biosynthesis of summer tea leaves
Ying Ye1 ,† , Ru-Yi Liu1 ,† , Xin Li2 , Xin-Qiang Zheng1 , Jian-Liang Lu1 , Yue-Rong Liang1 , Chao-Ling Wei3 , , Yong-Quan Xu2 and Jian-Hui Ye,1 ,
1Tea Research Institute, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, China
2Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, Tea Research Institute Chinese Academy of Agricultural Sciences, Hangzhou 310000, China
3State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 Changjiang West Road, Hefei 230036, China
*Corresponding author. E-mail: yqx33@126.com,jianhuiye@zju.edu.cn
Both authors contributed equally to the study.

Horticulture Research 11,
Article number: uhad231 (2024)
doi: https://doi.org/10.1093/hr/uhad231
Views: 25

Received: 26 Jun 2023
Accepted: 01 Nov 2023
Published online: 17 Nov 2023

Abstract

Flavonoids are important compounds in tea leaves imparting bitter and astringent taste, which also play key roles in tea plants responding to environmental stress. Our previous study showed that the expression level of CsMYB67 was positively correlated with the accumulation of flavonoids in tea leaves as exposed to sunlight. Here, we newly reported the function of CsMYB67 in regulating flavonoid biosynthesis in tea leaves. CsMYB67 was localized in the nucleus and responded to temperature. The results of transient expression assays showed the co-transformation of CsMYB67 and CsTTG1 promoted the transcription of CsANS promoter in the tobacco system. CsTTG1 was bound to the promoter of CsANS based on the results of yeast one-hybrid (Y1H) and transient expression assays, while CsMYB67 enhanced the transcription of CsANS through protein interaction with CsTTG1 according to the results of yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC). Thus, CsMYB67-CsTTG1 module enhanced the anthocyanin biosynthesis through up-regulating the transcription of CsANS. Besides, CsMYB67 also enhanced the transcription of CsFLS and CsUFGT through forming transcription factor complexes. The function of CsMYB67 on flavonoid biosynthesis in tea leaves was validated by gene suppression assay. As CsMYB67 was suppressed, the transcriptional level of CsFLS was greatly reduced, leading to a significant increase in the contents of total catechins and total anthocyanidins. Hence, CsMYB67 plays an important role in regulating the downstream pathway of flavonoid biosynthesis in summer tea leaves.