[1]

Li P, Fu J, Xu Y, Shen Y, Zhang Y, et al. 2022. CsMYB1 integrates the regulation of trichome development and catechins biosynthesis in tea plant domestication. New Phytologist 234:902−17

doi: 10.1111/nph.18026
[2]

Li J, Liu S, Chen P, Cai J, Tang S, et al. 2022. Systematic analysis of the R2R3-MYB family in Camellia sinensis: evidence for galloylated catechins biosynthesis regulation. Frontiers in Plant Science 12:782220

doi: 10.3389/fpls.2021.782220
[3]

Jin J, Zhou C, Ma C, Yao M, Ma J, et al. 2014. Identification on purine alkaloids of representative tea germplasms in China. Journal of Plant Genetic Resources 2:279−85

[4]

Zhong H, Wang Y, Qu F-R, Wei M-Y, Zhang C-Y, et al. 2022. A novel TCS allele conferring the high-theacrine and low-caffeine traits and having potential use in tea plant breeding. Horticulture Research 9:uhac191

doi: 10.1093/hr/uhac191
[5]

Jin J, Chai Y, Liu Y, Zhang J, Yao M, et all. 2018. Hongyacha, a naturally caffeine-free tea plant from Fujian, China. Journal of Agricultural and Food Chemistry 66:11311−19

doi: 10.1021/acs.jafc.8b03433
[6]

Ashihara H, Sano H, Crozier A. 2008. Caffeine and related purine alkaloids: biosynthesis, catabolism, function and genetic engineering. Phytochemistry 69:841−56

doi: 10.1016/j.phytochem.2007.10.029
[7]

Juliano LM, Griffiths RR. 2004. A critical review of caffeine withdrawal: empirical validation of symptoms and signs, incidence, severity, and associated features. Psychopharmacology 176:1−29

doi: 10.1007/s00213-004-2000-x
[8]

Tritsch N, Steger MC, Segatz V, Blumenthal P, Rigling M, et al. 2022. Risk assessment of caffeine and epigallocatechin gallate in coffee leaf tea. Foods 11:263

doi: 10.3390/foods11030263
[9]

Kato M, Mizuno K, Crozier A, Fujimura T, Ashihara H. 2000. Caffeine synthase gene from tea leaves. Nature 406:956−57

doi: 10.1038/35023072
[10]

Kato M, Kanehara T, Shimizu H, Suzuki T, Gillies FM, et al. 1996. Caffeine biosynthesis in young leaves of Camellia sinensis: In vitro studies on N-methyltransferase activity involved in the conversion of xanthosine to caffeine. Physiologia Plantarum 98:629−36

doi: 10.1111/j.1399-3054.1996.tb05720.x
[11]

Deng WW, Ashihara H. 2010. Profiles of purine metabolism in leaves and roots of Camellia sinensis seedlings. Plant and Cell Physiology 51:2105−18

doi: 10.1093/pcp/pcq175
[12]

Jin J, Yao M, Ma C, Ma J, Chen L. 2016. Association mapping of caffeine content with TCS1 in tea plant and its related species. Plant Physiology and Biochemistry 105:251−9

doi: 10.1016/j.plaphy.2016.04.032
[13]

Negishi O, Ozawa T, Imagawa H. 1992. Biosynthesis of caffeine from purine nucleotides in tea plant. Bioscience, Biotechnology, and Biochemistry 56:499−503

doi: 10.1271/bbb.56.499
[14]

Ashihara H, Kato M, Ye CX. 1998. Biosynthesis and metabolism of purine alkaloids in leaves of cocoa tea (Camellia ptilophylla). Journal of Plant Research 111:599−604

doi: 10.1007/BF02507798
[15]

Deng C, Ku X, Cheng L, Pan S, Fan L, et al. 2020. Metabolite and transcriptome profiling on xanthine alkaloids-fed tea plant (Camellia sinensis) shoot tips and roots reveal the complex metabolic network for caffeine biosynthesis and degradation. Frontiers in Plant Science 11:551288

doi: 10.3389/fpls.2020.551288
[16]

Li P, Ye Z, Fu J, Xu Y, Shen Y, et al. 2022. CsMYB184 regulates caffeine biosynthesis in tea plants. Plant Biotechnology Journal 20:1012−14

doi: 10.1111/pbi.13814
[17]

Yoneyama N, Morimoto H, Ye CX, Ashihara H, Mizuno K, Kato M. 2006. Substrate specificity of N-methyltransferase involved in purine alkaloids synthesis is dependent upon one amino acid residue of the enzyme. Molecular Genetics and Genomics 275:125−35

doi: 10.1007/s00438-005-0070-z
[18]

Teng J, Yan C, Zeng W, Zhang Y, Zeng Z, Huang Y. 2020. Purification and characterization of theobromine synthase in a Theobromine-Enriched wild tea plant (Camellia gymnogyna Chang) from Dayao Mountain, China. Food Chemistry 311:125875

doi: 10.1016/j.foodchem.2019.125875
[19]

Ma J, Jin J, Yao M, Ma C, Xu Y, et al. 2018. Quantitative trait loci mapping for theobromine and caffeine contents in tea plant (Camellia sinensis). Journal of Agricultural and Food Chemistry 66:13321−27

doi: 10.1021/acs.jafc.8b05355
[20]

Ogino A, Taniguchi F, Yoshida K, Matsumoto S, Fukuoka H, et al. 2019. A new DNA marker CafLess-TCS1 for selection of caffeine-less tea plants. Breeding Science 69:393−400

doi: 10.1270/jsbbs.18161
[21]

Yamada Y, Sato F. 2013. Transcription factors in alkaloid biosynthesis. In International Review of Cell and Molecular Biology, ed. Jeon KW. vol. 305. USA: Academic Press, Elsevier. pp. 339-82. https://doi.org/10.1016/B978-0-12-407695-2.00008-1

[22]

Wu Z, Li X, Liu Z, Li H, Wang Y, et al. 2015. Transcriptome-based discovery of AP2/ERF transcription factors related to temperature stress in tea plant (Camellia sinensis). Functional & Integrative Genomics 15:741−52

[23]

Zhao X, Zeng X, Lin N, Yu S, Fernie AR, et al. 2021. CsbZIP1-CsMYB12 mediates the production of bitter-tasting flavonols in tea plants (Camellia sinensis) through a coordinated activator–repressor network. Horticulture Research 8:110

doi: 10.1038/s41438-021-00545-8
[24]

Zhang Y, Li P, She G, Xu Y, Peng A, et al. 2021. Molecular basis of the distinct metabolic features in shoot tips and roots of tea plants (Camellia sinensis): Characterization of MYB regulator for root theanine synthesis. Journal of Agricultural and Food Chemistry 69:3415−29

doi: 10.1021/acs.jafc.0c07572
[25]

Ma W, Kang X, Liu P, She K, Zhang Y, et al. 2022. The NAC-like transcription factor CsNAC7 positively regulates the caffeine biosynthesis-related gene yhNMT1 in Camellia sinensis. Horticulture Research 9:uhab046

doi: 10.1093/hr/uhab046
[26]

Wang Y, Zheng P, Liu P, Song X, Guo F, et al. 2019. Novel insight into the role of withering process in characteristic flavor formation of teas using transcriptome analysis and metabolite profiling. Food Chemistry 272:313−22

doi: 10.1016/j.foodchem.2018.08.013
[27]

Shi J, Yang G, You Q, Sun S, Chen R, et al. 2021. Updates on the chemistry, processing characteristics, and utilization of tea flavonoids in last two decades (2001−2021). Critical Reviews in Food Science and Nutrition

doi: 10.1080/10408398.2021.2007353
[28]

Jin J, Ma J, Ma C, Yao M, Chen L. 2014. Determination of catechin content in representative Chinese Tea Germplasms. Journal of Agricultural and Food Chemistry 62:9436−41

doi: 10.1021/jf5024559
[29]

Li K, Liu C, Tam JC, Kwok H, Lau C, et al. 2014. In vitro and in vivo mechanistic study of a novel proanthocyanidin, GC-(4→8)-GCG from cocoa tea (Camellia ptilophylla) in antiangiogenesis. The Journal of Nutritional Biochemistry 25:319−28

doi: 10.1016/j.jnutbio.2013.11.006
[30]

Ou C, Ou Y, Kong Q, Sun H, Luo Y, et al. 2022. Variation of major quality-related chemical components in leaves of seed-propagated offspring in 'Cocoa Tea'. Journal of Tea 3:169−72

doi: 10.3969/j.issn.0577-8921.2022.03.008
[31]

Liu W, Feng Y, Yu S, Fan Z, Li X, et al. 2021. The Flavonoid Biosynthesis Network in Plants. International Journal of Molecular Sciences 22:12824

doi: 10.3390/ijms222312824
[32]

Mei S, Yu Z, Chen J, Zheng P, Sun B, et al. 2022. The physiology of postharvest tea (Camellia sinensis) leaves, according to metabolic phenotypes and gene expression analysis. Molecules 27:1708

doi: 10.3390/molecules27051708
[33]

Chen S, Zhou Y, Chen Y, Gu J. 2018. fastp: an ultra-fast all-in-one FASTQ preprocessor. Bioinformatics 34:i884−i890

doi: 10.1093/bioinformatics/bty560
[34]

Kim D, Langmead B, Salzberg SL. 2015. HISAT: a fast spliced aligner with low memory requirements. Nature Methods 12:357−60

doi: 10.1038/nmeth.3317
[35]

Liao Y, Smyth GK, Shi W. 2014. FeatureCounts: an efficient general purpose program for assigning sequence reads to genomic features. Bioinformatics 30:923−30

doi: 10.1093/bioinformatics/btt656
[36]

Bu D, Luo H, Huo P, Wang Z, Zhang S, et al. 2021. KOBAS-i: intelligent prioritization and exploratory visualization of biological functions for gene enrichment analysis. Nucleic Acids Research 49:W317−W325

doi: 10.1093/nar/gkab447
[37]

Robinson MD, McCarthy DJ, Smyth GK. 2010. edgeR: a Bioconductor package for differential expression analysis of digital gene expression data. Bioinformatics 26:139−40

doi: 10.1093/bioinformatics/btp616
[38]

Zheng Y, Jiao C, Sun H, Rosli HG, Pombo MA, et al. 2016. iTAK: A program for genome-wide prediction and classification of plant transcription factors, transcriptional regulators, and protein kinases. Molecular Plant 9:1667−70

doi: 10.1016/j.molp.2016.09.014
[39]

Livak KJ, Schmittgen TD. 2001. Analysis of relative gene expression data using real-time quantitative PCR and the 2−ΔΔCᴛ Method. Methods 25:402−8

doi: 10.1006/meth.2001.1262
[40]

Chen C, Chen H, Zhang Y, Thomas HR, Frank MH, et al. 2020. TBtools: an integrative toolkit developed for interactive analyses of big biological data. Molecular Plant 13:1194−202

doi: 10.1016/j.molp.2020.06.009
[41]

Wei C, Yang H, Wang S, Zhao J, Liu C, et al. 2018. Draft genome sequence of Camellia sinensis var. sinensis provides insights into the evolution of the tea genome and tea quality. Proceedings of the National Academy of Sciences of the United States of America 115:E4151−E4158

doi: 10.1073/pnas.1719622115
[42]

Ahmad MZ, Li P, She G, Xia E, Benedito VA, et al. 2020. Genome-wide analysis of serine carboxypeptidase-like acyltransferase gene family for evolution and characterization of enzymes involved in the biosynthesis of galloylated catechins in the tea plant (Camellia sinensis). Frontiers in Plant Science 11:848

doi: 10.3389/fpls.2020.00848
[43]

Yuan C, Shi S, Ye C. 1999. Phylogenetic relationship of Camellia ptilophylla Chang with its allied species and disintegration of its population. Acta Scientiarum Naturalium Universitatis Sunyatseni 38:72−76

[44]

Jin J, Yao M, Ma C, Ma J, Chen L. 2016. Natural allelic variations of TCS1 play a crucial role in caffeine biosynthesis of tea plant and its related species. Plant Physiology and Biochemistry 100:18−26

doi: 10.1016/j.plaphy.2015.12.020
[45]

Li Mm, Xue Jy, Wen Yl, Guo Hs, Sun Xq, et al. 2015. Transcriptomic analysis of Camellia ptilophylla and identification of genes associated with flavonoid and caffeine biosynthesis. Genetics and Molecular Research 14:18731−42

doi: 10.4238/2015.December.28.22
[46]

Zhu B, Chen L, Lu M, Zhang J, Han J, et al. 2019. Caffeine content and related gene expression: novel insight into caffeine metabolism in Camellia plants containing low, normal, and high caffeine concentrations. Journal of Agricultural and Food Chemistry 67:3400−11

doi: 10.1021/acs.jafc.9b00240
[47]

Zhang S, Jin J, Chen J, Ercisli S, Chen L. 2022. Purine alkaloids in tea plants: component. biosynthetic mechanism and genetic variation. Beverage Plant Research 2:13

doi: 10.48130/bpr-2022-0013