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Yu S, Li P, Zhao X, Tan M, Ahmad MZ, Xu Y, Tadege M, Zhao J. CsTCPs regulate shoot tip development and catechin biosynthesis in tea plant (Camellia sinensis). HORTICULTURE RESEARCH 2021; 8:104. [PMID: 33931613 PMCID: PMC8087681 DOI: 10.1038/s41438-021-00538-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Revised: 01/01/2021] [Accepted: 02/24/2021] [Indexed: 05/19/2023]
Abstract
The growth of leaves and biosynthesis of characteristic secondary metabolites are critically important for tea production and quality control. However, little is known about the coordinated regulation of leaf development and catechin biosynthesis in tea plants. Here, we reported that TCP TFs are involved in both catechin biosynthesis and leaf development. An integrated analysis of catechin profiling and CsTCP expression in different tissues of plants under various environmental conditions at different developmental stages indicated significant correlations between the transcript levels of CIN-type TCPs and catechin production. CIN-type CsTCP3 and CsTCP4 and PCF-type CsTCP14 interacted with the MYB-bHLH-WD40 repeat (MBW) complex by forming a CsTCP3-CsTT8 heterodimer and modulating the transactivation activity of the promoters of anthocyanin synthase (CsANS1) and anthocyanidin reductase (CsANR1). Four types of microRNA/target modules, miR319b/CsTCP3-4, miR164b/CsCUC, miR396/CsGRF-GIF, and miR165b/HD-ZIPIII ones, were also identified and characterized for their functions in the regulation of the development of tea plant shoot tips and leaf shape. The results of these modules were reflected by their different expression patterns in developing buds and leaves that had distinctly different morphologies in three different tea plant varieties. Their roles in the regulation of catechin biosynthesis were also further verified by manipulation of microRNA319b (miR319b), which targets the transcripts of CsTCP3 and CsTCP4. Thus, CsTCPs represent at least one of these important groups of TFs that can integrate tea plant leaf development together with secondary metabolite biosynthesis. Our study provides new insight into shoot tip development and catechin production in tea plants and lays a foundation for further mechanistic understanding of the regulation of tea plant leaf development and secondary metabolism.
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Affiliation(s)
- Shuwei Yu
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, 230036, China
| | - Penghui Li
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, 230036, China
| | - Xuecheng Zhao
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, 230036, China
| | - Mangmang Tan
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, 230036, China
| | - Muhammad Zulfiqar Ahmad
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, 230036, China
| | - Yujie Xu
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, 230036, China
| | - Million Tadege
- Department of Plant and Soil Sciences, Institute for Agricultural Biosciences, Oklahoma State University, 3210 Sam Noble Parkway, Ardmore, OK, 73401, USA
| | - Jian Zhao
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, 230036, China.
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Yang T, Xie Y, Lu X, Yan X, Wang Y, Ma J, Cheng X, Lin S, Bao S, Wan X, Lucas WJ, Zhang Z. Shading Promoted Theanine Biosynthesis in the Roots and Allocation in the Shoots of the Tea Plant ( Camellia sinensis L.) Cultivar Shuchazao. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:4795-4803. [PMID: 33861578 DOI: 10.1021/acs.jafc.1c00641] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Shading was thought as an effective approach to increase theanine in harvested tea shoots. Previous studies offered conflicting findings, perhaps since the integration of theanine metabolism and transport in different tissues was not considered. Theanine is synthesized primarily in the roots and is then transported, via the vascular system, to new vegetative tissues. Here, we found that theanine increased in the stem, was reduced in the leaf, and remained stable in the roots, under shading conditions. Notably, in tea roots, shading significantly increased ethylamine and activated the theanine biosynthesis pathway and theanine transporter genes. Furthermore, shading significantly increased the expression of theanine transporter genes, CsAAP2/4/5/8, in the stem, while decreasing the expression of CsAAP1/2/4/5/6 in the leaf, in accordance with shading effects on theanine levels in these tissues. These findings reveal that shading of tea plants promotes theanine biosynthesis and allocation in different tissues, processes which appear to involve the theanine biosynthesis pathway enzymes and AAP family of theanine transporters.
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Affiliation(s)
- Tianyuan Yang
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, Anhui 230036, China
| | - Yunxia Xie
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, Anhui 230036, China
| | - Xin Lu
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, Anhui 230036, China
| | - Xiaomei Yan
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, Anhui 230036, China
| | - Yan Wang
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, Anhui 230036, China
| | - Jingzhen Ma
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, Anhui 230036, China
| | - Xunmin Cheng
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, Anhui 230036, China
| | - Shijia Lin
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, Anhui 230036, China
| | - Shilai Bao
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Xiaochun Wan
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, Anhui 230036, China
| | - William J Lucas
- Department of Plant Biology, College of Biological Sciences, University of California, Davis, California 95616, United States
| | - Zhaoliang Zhang
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, Anhui 230036, China
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Zhang Y, Li P, She G, Xu Y, Peng A, Wan X, Zhao J. 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 2021; 69:3415-3429. [PMID: 33719427 DOI: 10.1021/acs.jafc.0c07572] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The physiological and metabolic differences between shoot tips and roots of tea plants are significant, and understanding them is required for improvement of tea quality and plant growth. A high-quality full-length transcriptome sequencing on tea plant roots and shoot tips by PacBio SMRT technology was done to gain a further understanding. Approximately 160699 and 166120 full-length transcripts were recovered in roots and shoots, respectively, including 31232 and 41068 novel isoforms and 16960 and 26029 alternative splicing (AS) isoforms. These supported 21699 full-length reads and 31232 and 41068 novel transcripts from root and shoot, respectively, including 1679 long noncoding RNAs (lncRNAs) and 2772 fusion transcripts, which significantly upgrade the Camellia sinensis genome annotation. The respective 6475 and 6981 transcripts in roots and shoots differ in 3'-untranslated regions. Meanwhile, extensive analyses of novel transcripts, ASs, and lncRNAs also revealed a large number of ASs and lincRNAs closely related to the regulation of characteristic secondary metabolites including catechins, theanine, and caffeine. Finally, a root-specific CsMYB6 was characterized to regulate theanine biosynthesis by genetic and molecular analyses. CsMYB6 directly bound to and activate the promoter of theanine synthetase gene (CsTSI). The study lays a foundation for the further investigation of metabolic genomics and regulation in tea plants.
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Affiliation(s)
- Yanrui Zhang
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, People's Republic of China
| | - Penghui Li
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, People's Republic of China
| | - Guangbiao She
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, People's Republic of China
| | - Yujie Xu
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, People's Republic of China
| | - Anqi Peng
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, People's Republic of China
| | - Xiaochun Wan
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, People's Republic of China
| | - Jian Zhao
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, People's Republic of China
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Fang K, Xia Z, Li H, Jiang X, Qin D, Wang Q, Wang Q, Pan C, Li B, Wu H. Genome-wide association analysis identified molecular markers associated with important tea flavor-related metabolites. HORTICULTURE RESEARCH 2021; 8:42. [PMID: 33642595 PMCID: PMC7917101 DOI: 10.1038/s41438-021-00477-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 12/15/2020] [Accepted: 12/17/2020] [Indexed: 05/02/2023]
Abstract
The characteristic secondary metabolites in tea (theanine, caffeine, and catechins) are important factors contributing to unique tea flavors. However, there has been relatively little research on molecular markers related to these metabolites. Thus, we conducted a genome-wide association analysis of the levels of these tea flavor-related metabolites in three seasons. The theanine, caffeine, and catechin levels in Population 1 comprising 191 tea plant germplasms were examined, which revealed that their heritability exceeded 0.5 in the analyzed seasons, with the following rank order (highest to lowest heritabilities): (+)-catechin > (-)-gallocatechin gallate > caffeine = (-)-epicatechin > (-)-epigallocatechin-3-gallate > theanine > (-)-epigallocatechin > (-)-epicatechin-3-gallate > catechin gallate > (+)-gallocatechin. The SNPs detected by amplified-fragment SNP and methylation sequencing divided Population 1 into three groups and seven subgroups. An association analysis yielded 307 SNP markers related to theanine, caffeine, and catechins that were common to all three seasons. Some of the markers were pleiotropic. The functional annotation of 180 key genes at the SNP loci revealed that FLS, UGT, MYB, and WD40 domain-containing proteins, as well as ATP-binding cassette transporters, may be important for catechin synthesis. KEGG and GO analyses indicated that these genes are associated with metabolic pathways and secondary metabolite biosynthesis. Moreover, in Population 2 (98 tea plant germplasm resources), 30 candidate SNPs were verified, including 17 SNPs that were significantly or extremely significantly associated with specific metabolite levels. These results will provide a foundation for future research on important flavor-related metabolites and may help accelerate the breeding of new tea varieties.
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Affiliation(s)
- Kaixing Fang
- Tea Research Institute, Guangdong Academy of Agricultural Sciences; Guangdong Key Laboratory of Tea Plant Resources Innovation & Utilization, Guangzhou, 510640, China
| | - Zhiqiang Xia
- Institute of Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, 570100, China
- Hainan University, Haikou, 570228, China
| | - Hongjian Li
- Tea Research Institute, Guangdong Academy of Agricultural Sciences; Guangdong Key Laboratory of Tea Plant Resources Innovation & Utilization, Guangzhou, 510640, China
| | - Xiaohui Jiang
- Tea Research Institute, Guangdong Academy of Agricultural Sciences; Guangdong Key Laboratory of Tea Plant Resources Innovation & Utilization, Guangzhou, 510640, China
| | - Dandan Qin
- Tea Research Institute, Guangdong Academy of Agricultural Sciences; Guangdong Key Laboratory of Tea Plant Resources Innovation & Utilization, Guangzhou, 510640, China
| | - Qiushuang Wang
- Tea Research Institute, Guangdong Academy of Agricultural Sciences; Guangdong Key Laboratory of Tea Plant Resources Innovation & Utilization, Guangzhou, 510640, China
| | - Qing Wang
- Tea Research Institute, Guangdong Academy of Agricultural Sciences; Guangdong Key Laboratory of Tea Plant Resources Innovation & Utilization, Guangzhou, 510640, China
| | - Chendong Pan
- Tea Research Institute, Guangdong Academy of Agricultural Sciences; Guangdong Key Laboratory of Tea Plant Resources Innovation & Utilization, Guangzhou, 510640, China
| | - Bo Li
- Tea Research Institute, Guangdong Academy of Agricultural Sciences; Guangdong Key Laboratory of Tea Plant Resources Innovation & Utilization, Guangzhou, 510640, China
| | - Hualing Wu
- Tea Research Institute, Guangdong Academy of Agricultural Sciences; Guangdong Key Laboratory of Tea Plant Resources Innovation & Utilization, Guangzhou, 510640, China.
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Krishnatreya DB, Agarwala N, Gill SS, Bandyopadhyay T. Understanding the role of miRNAs for improvement of tea quality and stress tolerance. J Biotechnol 2021; 328:34-46. [PMID: 33421509 DOI: 10.1016/j.jbiotec.2020.12.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 12/04/2020] [Accepted: 12/28/2020] [Indexed: 12/18/2022]
Abstract
MicroRNAs (miRNAs) are an emerging class of small non-coding RNAs that exhibit important role in regulation of gene expression, mostly through the mechanism of cleavage and/or inhibition of translation of target mRNAs during or after transcription. Although much has been unravelled about the role of miRNAs in diverse biological processes like maintenance of functional integrity of genes and genome, growth and development, metabolism, and adaptive responses towards biotic and abiotic stresses in plants, not much is known on their specific roles in majority of cash crops - an area of investigation with potentially significant and gainful economic implications. Tea (Camellia sinensis) is globally the second most consumed beverage after water and its cultivation has major agro-economic and social ramifications. In recent years, global tea production has been greatly challenged by many biotic and abiotic stress factors and a deeper understanding of molecular processes regulating stress adaptation in this largely under investigated crop stands to significantly facilitate potential crop improvement strategies towards durable stress tolerance. This review endeavours to highlight recent advances in our understanding of the role of miRNAs in regulating stress tolerance traits in tea plant with additional focus on their role in determining tea quality attributes.
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Affiliation(s)
| | - Niraj Agarwala
- Department of Botany, Gauhati University, Jalukbari, Guwahati, Assam, 781014, India.
| | - Sarvajeet Singh Gill
- Center for Biotechnology, Maharshi Dayanand University, Rohtak, Haryana, 124001, India
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Zeng L, Zhou X, Liao Y, Yang Z. Roles of specialized metabolites in biological function and environmental adaptability of tea plant (Camellia sinensis) as a metabolite studying model. J Adv Res 2020; 34:159-171. [PMID: 35024188 PMCID: PMC8655122 DOI: 10.1016/j.jare.2020.11.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 10/12/2020] [Accepted: 11/04/2020] [Indexed: 12/21/2022] Open
Abstract
Background Aim of review Key scientific concepts of review
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57
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Li P, Xu Y, Zhang Y, Fu J, Yu S, Guo H, Chen Z, Chen C, Yang X, Wang S, Zhao J. Metabolite Profiling and Transcriptome Analysis Revealed the Chemical Contributions of Tea Trichomes to Tea Flavors and Tea Plant Defenses. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:11389-11401. [PMID: 32852206 DOI: 10.1021/acs.jafc.0c04075] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Tea trichomes contain special flavor-determining metabolites; however, little is known about how and why tea trichomes produce them. Integrated metabolite and transcriptome profiling on tea trichomes in comparison with that on leaves showed that trichomes contribute to tea plant defense and tea flavor and nutritional quality. These unicellular, nonglandular, and unbranched tea trichomes produce a wide array of tea characteristic metabolites, such as UV-protective flavonoids, insect-toxic caffeine, herbivore-defensive volatiles, and theanine, as evidenced by the expression of whole sets of genes involved in different metabolic pathways. Both dry and fresh trichomes contain several volatiles and flavonols that were not found or at much low levels in trichome-removed leaves, including benzoic acid derivatives, lipid oxidation derivatives, and monoterpene derivatives. Trichomes also specifically expressed many disease signaling genes and various antiherbivore or antiabiotic peptides. Trichomes are one of the domestication traits in tea plants. Tea trichomes contribute to tea plant defenses and tea flavors.
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Affiliation(s)
- Penghui Li
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, China
| | - Yujie Xu
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, China
| | - Yanrui Zhang
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, China
| | - Jiamin Fu
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, China
| | - Shuwei Yu
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, China
| | - Huimin Guo
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, China
| | - Zhihui Chen
- Tea Research Institute, Fujian Academy of Agricultural Sciences, Fuzhou 350013, China
| | - Changsong Chen
- Tea Research Institute, Fujian Academy of Agricultural Sciences, Fuzhou 350013, China
| | - Xiaogen Yang
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, China
| | - Shucai Wang
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun 130024, China
| | - Jian Zhao
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, China
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58
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Deng C, Ku X, Cheng LL, Pan SA, Fan L, Deng WW, Zhao J, Zhang ZZ. 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 2020; 11:551288. [PMID: 33013969 PMCID: PMC7509060 DOI: 10.3389/fpls.2020.551288] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 08/13/2020] [Indexed: 05/08/2023]
Abstract
While caffeine is one of the most important bioactive metabolites for tea as the most consumed non-alcohol beverage, its biosynthesis and catabolism in tea plants are still not fully understood. Here, we integrated purine alkaloid profiling and transcriptome analysis on shoot tips and roots fed with caffeine, theophylline, or theobromine to gain further understanding of caffeine biosynthesis and degradation. Shoot tips and roots easily took up and accumulated high concentrations of alkaloids, but roots showed much faster caffeine and theophylline degradation rates than shoot tips, which only degraded theophylline significantly but almost did not degrade caffeine. Clearly feedback inhibition on caffeine synthesis or inter-conversion between caffeine, theophylline, and theobromine, and 3-methylxanthine had been observed in alkaloids-fed shoot tips and roots, and these were also evidenced by significant repression of TCS and MXMT genes critical for caffeine biosynthesis. Among these responsively repressed genes, two highly expressed genes TCS-4 and TCS-8 were characterized for their enzyme activity. While we failed to detect TCS-4 activity, TCS-8 displayed N-methyltransferase activities towards multiple substrates, supporting the complex metabolic network in caffeine biosynthesis in tea plants since at least 13 TCS-like N-methyltransferase genes may function redundantly. This study provides new insight into complex metabolic networks of purine alkaloids in tea plants.
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Affiliation(s)
- Cheng Deng
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, China
| | - Xiuping Ku
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, China
| | - Lin-Lin Cheng
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, China
| | - Si-An Pan
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, China
| | - Limao Fan
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, China
| | - Wei-Wei Deng
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, China
| | - Jian Zhao
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, China
| | - Zheng-Zhu Zhang
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, China
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Ahmad MZ, Li P, She G, Xia E, Benedito VA, Wan XC, Zhao J. 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 2020; 11:848. [PMID: 32670320 PMCID: PMC7330524 DOI: 10.3389/fpls.2020.00848] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 05/26/2020] [Indexed: 05/14/2023]
Abstract
Tea (Camellia sinensis L.) leaves synthesize and concentrate a vast array of galloylated catechins (e.g., EGCG and ECG) and non-galloylated catechins (e.g., EGC, catechin, and epicatechin), together constituting 8%-24% of the dry leaf mass. Galloylated catechins account for a major portion of soluble catechins in tea leaves (up to 75%) and make a major contribution to the astringency and bitter taste of the green tea, and their pharmacological activity for human health. However, the catechin galloylation mechanism in tea plants is largely unknown at molecular levels. Previous studies indicated that glucosyltransferases and serine carboxypeptidase-like acyltransferases (SCPL) might be involved in the process. However, details about the roles of SCPLs in the biosynthesis of galloylated catechins remain to be elucidated. Here, we performed the genome-wide identification of SCPL genes in the tea plant genome. Several SCPLs were grouped into clade IA, which encompasses previously characterized SCPL-IA enzymes with an acylation function. Twenty-eight tea genes in this clade were differentially expressed in young leaves and vegetative buds. We characterized three SCPL-IA enzymes (CsSCPL11-IA, CsSCPL13-IA, CsSCPL14-IA) with galloylation activity toward epicatechins using recombinant enzymes. Not only the expression levels of these SCPLIA genes coincide with the accumulation of galloylated catechins in tea plants, but their recombinant enzymes also displayed β-glucogallin:catechin galloyl acyltransferase activity. These findings provide the first insights into the identities of genes encoding glucogallin:catechin galloyl acyltransferases with an active role in the biosynthesis of galloylated catechins in tea plants.
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Affiliation(s)
- Muhammad Zulfiqar Ahmad
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, China
| | - Penghui Li
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, China
| | - Guangbiao She
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, China
| | - Enhua Xia
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, China
| | - Vagner A. Benedito
- Division of Plant & Soil Sciences, West Virginia University, Morgantown, WV, United States
| | - Xiao Chun Wan
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, China
| | - Jian Zhao
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, China
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