转录因子CsMYB75-like-2调控茶树花青素合成的分子机制研究

摘要/Abstract

摘要： 花青素作为植物重要的次生代谢产物,赋予植物多彩的颜色,吸引昆虫授粉,抵抗生物和非生物胁迫,对植物生长发育和繁殖具有重要意义。以高花青素茶树品种‘紫娟’为试验材料,探究R2R3-MYB型转录因子CsMYB75-like-2对茶树花青素合成的调控机制。结果表明,CsMYB75-like-2属于花青素合成的SG6亚族,该基因在紫化茶树品种中的表达量显著高于绿色茶树品种,且在幼嫩组织特异性高表达,不同茶树品种中CsMYB75-like-2的蛋白编码区高度保守。亚细胞定位和酵母转录活性试验证实,CsMYB75-like-2是一个核膜共定位的激活型转录因子;遮阴试验表明,CsMYB75-like-2及下游基因（CsDFR和CsFLS）的表达水平与花青素含量呈正相关。与CsMYB75-like-1功能不同,CsMYB75-like-2对花青素合成关键基因CsANS无直接调控作用;其与CsMYB308、CsMYB114等MYB家族成员形成互作调控网络。研究结果可为解析茶树花青素合成分子机制及紫化茶树品种选育提供理论依据。

关键词: 茶树, 花青素, CsMYB75-like-2, 调控机制

Abstract: Anthocyanins, as vital plant secondary metabolites, contribute to pigmentation, pollinator attraction and stress resistance, significantly impacting plant development. This study elucidated the regulatory role of the R2R3-MYB transcription factor CsMYB75-like-2 in anthocyanin biosynthesis in tea plants (Camellia sinensis), utilizing the anthocyanin-rich cultivar ‘Zijuan’ as the material. Phylogenetic analysis reveals that CsMYB75-like-2 belongs to the SG6 subfamily of anthocyanin-related transcription factors. CsMYB75-like-2 is expressed at higher levels in purple tea cultivars than in green ones and is specifically enriched in young tissues. Its coding sequence remains highly conserved across cultivars. Subcellular localization confirmed its residence in the nuclear membrane, and yeast assays demonstrated its function as a transcriptional activator. Shade treatment experiments showed a positive correlation between CsMYB75-like-2 expression, its downstream genes (CsDFR and CsFLS) as well as anthocyanin accumulation. However, unlike CsMYB75-like-1, CsMYB75-like-2 does not directly bind to or activate the key anthocyanin biosynthesis gene CsANS. Instead, it forms an interactive regulatory network with other MYB family members, including CsMYB308 and CsMYB114. These findings provided crucial insights into the molecular mechanisms governing anthocyanin biosynthesis in tea plants and offer valuable targets for breeding enhanced purple tea cultivars.

Key words: Camellia sinensis, anthocyanins, CsMYB75-like-2, regulation mechanisms

中图分类号:

S571.1
Q52

周慧, 崔悠, 陈雯剑, 杜悦阳, 张欢, 苏鸿锋, 张凯凯, 张凌云. 转录因子CsMYB75-like-2调控茶树花青素合成的分子机制研究[J]. 茶叶科学, 2026, 46(1): 20-34.

ZHOU Hui, CUI You, CHEN Wenjian, DU Yueyang, ZHANG Huan, SU Hongfeng, ZHANG Kaikai, ZHANG Lingyun. Molecular Mechanisms Underlying the Regulation of Anthocyanin Biosynthesis by the Transcription Factor CsMYB75-like-2 in Tea Plants (Camellia sinensis)[J]. Journal of Tea Science, 2026, 46(1): 20-34.

参考文献

[1] 夏恩华, 韦朝领, 宛晓春. 茶树生物学“十三五”进展及“十四五”发展方向[J]. 中国茶叶, 2021, 43(9): 31-41.
Xia E H, Wei C L, Wan X C.Tea plant biology progress during the 13th five-year plan period and development direction in the 14th five-year plan period[J]. China Tea, 2021, 43(9): 31-41.
[2] Dong Y H, Wu X, Han L, et al.The potential roles of dietary anthocyanins in inhibiting vascular endothelial cell senescence and preventing cardiovascular diseases[J]. Nutrients, 2022, 14(14): 2836. doi: 10.3390/nu14142836.
[1] Lü H P, Dai W D, Tan J F, et al.Identification of the anthocyanins from the purple leaf coloured tea cultivar Zijuan (Camellia sinensis var. assamica) and characterization of their antioxidant activities[J]. Journal of Functional Foods, 2015, 17: 449-458. doi: 10.1016/j.jff.2015.05.043.
[2] Singh K, Kumar S, Rani A, et al.Phenylalanine ammonia-lyase (PAL) and cinnamate 4-hydroxylase (C4H) and catechins (flavan-3-ols) accumulation in tea[J]. Functional & Integrative Genomics, 2009, 9(1): 125-134.
[3] Rani A, Singh K, Sood P, et al.p-Coumarate: CoA ligase as a key gene in the yield of catechins in tea [Camellia sinensis (L.) O. Kuntze][J]. Functional & Integrative Genomics, 2009, 9(2): 271-275.
[4] Singh K, Rani A, Kumar S, et al.Early gene of the flavonoid pathway, flavanone 3-hydroxylase, exhibits a positive relationship with the concentration of catechins in tea (Camellia sinensis)[J]. Tree Physiology, 2008, 28(9): 1349-1356.
[5] 马春雷, 陈亮. 茶树功能基因分离克隆研究进展[J]. 分子植物育种, 2006, 4(s1): 16-22.
Ma C L, Chen L.Research progress on isolation and cloning of functional genes in tea plant[J]. Molecular Plant Breeding, 2006, 4(s1): 16-22.
[6] 马春雷, 赵丽萍, 张亚丽, 等. 茶树查尔酮异构酶基因克隆及序列分析[J]. 茶叶科学, 2007, 27(2): 127-132.
Ma C L, Zhao L P, Zhang Y L, et al.Molecular cloning and sequence analysis of chalcone isomerase gene of tea plant (Camellia sinensis)[J]. Jouranl of Tea Science, 2007, 27(2): 127-132.
[7] 金琦芳, 陈志丹, 孙威江, 等. 茶树CsANS基因及其启动子的克隆与生物信息学分析[J]. 茶叶科学, 2016, 36(2): 219-228.
Jin Q F, Chen Z D, Sun W J, et al.Cloning and bioinformatical analysis of anthocyanin synthase gene and its promoter in Camellia sinensis[J]. Journal of Tea Science, 2016, 36(2): 219-228.
[8] Hong G J, Wang J, Zhang Y, et al.Biosynthesis of catechin components is differentially regulated in dark-treated tea (Camellia sinensis L.)[J]. Plant Physiology Biochemistry, 2014, 78: 49-52. doi: 10.1016/j.plaphy.2014.02.017.
[9] Jiang L, Shen X, Shoji T, et al.Characterization and activity of anthocyanins in Zijuan tea (Camellia sinensis var. kitamura)[J]. Journal Agricultural Food Chemistry, 2013, 61(13): 3306-3310.
[10] Lai Y S, Li S, Tang Q, et al.The dark-purple tea cultivar ‘Ziyan’ accumulates a large amount of delphinidin-related anthocyanins[J]. Journal Agricultural Food Chemistry, 2016, 64(13): 2719-2726.
[11] Kerio L C, Wachira F N, Wanyoko J K, et al.Characterization of anthocyanins in Kenyan teas: extraction and identification[J]. Food Chemistry, 2012, 131(1): 31-38.
[12] Saito T, Honma D, Tagashira M, et al.Anthocyanins from new red leaf tea ‘Sunrouge’[J]. Journal of Agricultural and Food Chemistry, 2011, 59(9): 4779-4782.
[13] 蒋会兵, 夏丽飞, 田易萍, 等. 基于转录组测序的紫芽茶树花青素合成相关基因分析[J]. 植物遗传资源学报, 2018, 19(5): 967-978.
Jiang H B, Xia L F, Tian Y P, et al.Transcriptome analysis of anthocyanin synthesis related genes in purple bud tea plant[J]. Journal of Plant Genetic Resources, 2018, 19(5): 967-978.
[14] Wang Y Q, Jin J Q, Zhang R, et al. Association analysis of BSA-seq, BSR-seq, and RNA-seq reveals key genes involved in purple leaf formation in a tea population (Camellia sinensis) [J]. Horticulture Research, 2024, 11(9): uhae191. doi: 10.1093/hr/uhae191.
[15] Wei K, Wang L, Zhang Y, et al.A coupled role for CsMYB75 and CsGSTF1 in anthocyanin hyperaccumulation in purple tea[J]. Plant Journal, 2019, 97(5): 825-840.
[16] 李智. 不同环境因子调控茶树紫色芽叶形成的分子机制研究[D]. 泰安: 山东农业大学, 2014.
Li Z.Research on the molecular mechanism of different environmental factors regulating the formation of purple buds and leaves in tea tree [D]. Tai'an: Shandong Agricultural University, 2014.
[17] Li W, Tan L Q, Zou Y, et al.The effects of ultraviolet A/B treatments on anthocyanin accumulation and gene expression in dark-purple tea cultivar ‘Ziyan’ (Camellia sinensis)[J]. Molecules, 2020, 25(2): 354. doi: 10.3390/molecules25020354.
[18] Zhang K K, Lin C Y, Chen B Y, et al.A light responsive transcription factor CsbHLH89 positively regulates anthocyanidin synthesis in tea (Camellia sinensis)[J]. Scientia Horticulturae, 2024, 327: 112784. doi: 10.1016/j.scienta.2023.112784.
[19] Singh K, Kumar S, Yadav S K, et al.Characterization of dihydroflavonol 4-reductase cDNA in tea [Camellia sinensis (L.) O. Kuntze][J]. Plant Biotechnology Reports, 2009, 3(1): 95-101.
[20] Li X, Ahammed G J, Zhang X, et al.Melatonin-mediated regulation of anthocyanin biosynthesis and antioxidant defense confer tolerance to arsenic stress in Camellia sinensis L[J]. Journal Hazardous Materials, 2021, 403: 123922. doi: 10.1016/j.jhazmat.2020.123922.
[21] Lynch M, Conery J S.The evolutionary fate and consequences of duplicate genes[J]. Science, 2000, 290(5494): 1151-1155.
[22] Wang P Q, Ma G L, Zhang L J, et al.A sucrose-induced MYB (SIMYB) transcription factor promoting proanthocyanidin accumulation in the tea plant (Camellia sinensis)[J]. Journal of Agricultural Food Chemistry, 2019, 67(5): 1418-1428.
[23] Sawano H, Matsuzaki T, Usui T, et al.Double-stranded RNA-binding protein DRB3 negatively regulates anthocyanin biosynthesis by modulating PAP1 expression in Arabidopsis thaliana[J]. Journal of Plant Research, 2017, 130(1): 45-55.
[24] Zhou H, Chen B Y, Du Y Y, et al.CsMYB308 as a repressive transcription factor inhibits anthocyanin biosynthesis in tea plants[J]. Plant Physiology Biochemistry, 2025, 222: 109662. doi: 10.1016/j.plaphy.
2025.109662.
[25] 笈小龙. ChMYB1调控欧李花青素合成的分子机制[D]. 哈尔滨: 东北林业大学, 2023.
Ji X L.Molecular mechanism of ChMYB1 regulating Cerasus humilis anthocyanin synthesis [D]. Harbin: Northeast Forestry University, 2023.
[26] 苏鸿锋. 茶树花青素合成酶基因的表达特征及上游MYB调控因子鉴定[D]. 广州: 华南农业大学, 2024.
Su H F.Research on the expression of anthocyanin synthase gene and identification of its upstream MYB regulatorys in tea plants (Camellia sinensis) [D]. Guangzhou: South China Agricultural University, 2024.
[27] Mariyam S, Kumar V, Roychoudhury A, et al.Functional diversification and mechanistic insights of MYB transcription factors in mediating plant growth and development, secondary metabolism, and stress responses[J]. Journal of Plant Growth Regulation, 2025, 44(4): 1465-1484.
[28] Fang F, Zhang X L, Luo H H, et al.An intracellular laccase is responsible for epicatechin-mediated anthocyanin degradation in litchi fruit pericarp[J]. Plant Physiology, 2015, 169(4): 2391-2408.
[29] Zipor G, Duarte P, Carqueijeiro I, et al.In planta anthocyanin degradation by a vacuolar class Ⅲ peroxidase in Brunfelsia calycina flowers[J]. New Phytologist, 2015, 205(2): 653-665.
[30] Maritim T K, Korir R K, Nyabundi K W, et al.Molecular regulation of anthocyanin discoloration under water stress and high solar irradiance in pluckable shoots of purple tea cultivar[J]. Planta, 2021, 254(5): 85. doi: 10.1007/s00425-
021-03736-8.
[31] Ruan H X, Shi X X, Gao L P, et al. Functional analysis of the dihydroflavonol 4-reductase family of Camellia sinensis: exploiting key amino acids to reconstruct reduction activity [J]. Horticultura Research, 2022, 9: uhac098. doi: 10.1093/hr/uhac098.
[32] Zhang C Y, Liu H R, Wang J Y, et al. A key mutation in magnesium chelatase I subunit leads to a chlorophyll-deficient mutant of tea (Camellia sinensis) [J]. Jounal Experimental Botany, 2024, 75(3): 935-946.
[33] Ma Y Y, Shi J C, Wang D J, et al.A point mutation in the gene encoding magnesium chelatase I subunit influences strawberry leaf color and metabolism[J]. Plant Physiology, 2023, 192(4): 2737-2755.
[34] Yoshida K, Ma D, Constabel C P.The MYB182 protein down-regulates proanthocyanidin and anthocyanin biosynthesis in poplar by repressing both structural and regulatory flavonoid genes[J]. Plant Physiology, 2015, 167(3): 693-710.
[35] Xu W J, Dubos C, Lepiniec L.Transcriptional control of flavonoid biosynthesis by MYB-bHLH-WDR complexes[J]. Trends Plant Science, 2015, 20(3): 176-185.
[36] Huang D, Tang Z Z, Fu J L, et al.CsMYB3 and CsRuby1 form an ‘activator-and-repressor’ loop for the regulation of anthocyanin biosynthesis in Citrus[J]. Plant and Cell Physiology, 2020, 61(2): 318-330.
[37] Li P H, Fu J M, Xu Y J, et al.CsMYB1 integrates the regulation of trichome development and catechins biosynthesis in tea plant domestication[J]. New Phytologist, 2022, 234(3): 902-917.
[38] Zhao X C, Li P, Zuo H, et al.CsMYBL2 homologs modulate the light and temperature stress-regulated anthocyanin and catechins biosynthesis in tea plants (Camellia sinensis)[J]. Plant Journal, 2023, 115(4): 1051-1070.
[3] 孙彬妹. 茶树MYB转录因子CsAN1调控花青素的作用机制研究[D]. 广州: 华南农业大学, 2016.
Sun B M.Research on the mechanism of action of tea tree MYB transcription factor CsAN1 in regulating anthocyanins [D]. Guangzhou: South China Agricultural University, 2016.