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Reimer JJ, Thiele B, Biermann RT, Junker-Frohn LV, Wiese-Klinkenberg A, Usadel B, Wormit A. Tomato leaves under stress: a comparison of stress response to mild abiotic stress between a cultivated and a wild tomato species. PLANT MOLECULAR BIOLOGY 2021; 107:177-206. [PMID: 34677706 PMCID: PMC8553704 DOI: 10.1007/s11103-021-01194-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 09/16/2021] [Indexed: 05/03/2023]
Abstract
Tomato is one of the most produced crop plants on earth and growing in the fields and greenhouses all over the world. Breeding with known traits of wild species can enhance stress tolerance of cultivated crops. In this study, we investigated responses of the transcriptome as well as primary and secondary metabolites in leaves of a cultivated and a wild tomato to several abiotic stresses such as nitrogen deficiency, chilling or warmer temperatures, elevated light intensities and combinations thereof. The wild species responded different to varied temperature conditions compared to the cultivated tomato. Nitrogen deficiency caused the strongest responses and induced in particular the secondary metabolism in both species but to much higher extent in the cultivated tomato. Our study supports the potential of a targeted induction of valuable secondary metabolites in green residues of horticultural production, that will otherwise only be composted after fruit harvest. In particular, the cultivated tomato showed a strong induction in the group of mono caffeoylquinic acids in response to nitrogen deficiency. In addition, the observed differences in stress responses between cultivated and wild tomato can lead to new breeding targets for better stress tolerance.
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Affiliation(s)
- Julia J Reimer
- Institute for Biology I, RWTH Aachen University, Worringer Weg 3, 52074, Aachen, Germany
- Bioeconomy Science Center, c/o Forschungszentrum Jülich GmbH, 52425, Jülich, Germany
- Forschungszentrum Jülich GmbH, PtJ, 52425, Jülich, Germany
| | - Björn Thiele
- Forschungszentrum Jülich GmbH, Institute of Bio- and Geosciences, Plant Sciences (IBG-2), 52425, Jülich, Germany
- Forschungszentrum Jülich GmbH, Institute of Bio- and Geosciences, Agrosphere (IBG-3), 52425, Jülich, Germany
- Bioeconomy Science Center, c/o Forschungszentrum Jülich GmbH, 52425, Jülich, Germany
| | - Robin T Biermann
- Institute for Biology I, RWTH Aachen University, Worringer Weg 3, 52074, Aachen, Germany
- Leibniz Institute of Vegetable and Ornamental Crops (IGZ) e.V., 14979, Großbeeren, Germany
| | - Laura V Junker-Frohn
- Forschungszentrum Jülich GmbH, Institute of Bio- and Geosciences, Plant Sciences (IBG-2), 52425, Jülich, Germany
- Bioeconomy Science Center, c/o Forschungszentrum Jülich GmbH, 52425, Jülich, Germany
| | - Anika Wiese-Klinkenberg
- Forschungszentrum Jülich GmbH, Institute of Bio- and Geosciences, Plant Sciences (IBG-2), 52425, Jülich, Germany
- Forschungszentrum Jülich GmbH, Institute of Bio- and Geosciences, Bioinformatics (IBG-4), 52425, Jülich, Germany
- Bioeconomy Science Center, c/o Forschungszentrum Jülich GmbH, 52425, Jülich, Germany
| | - Björn Usadel
- Institute for Biology I, RWTH Aachen University, Worringer Weg 3, 52074, Aachen, Germany
- Forschungszentrum Jülich GmbH, Institute of Bio- and Geosciences, Plant Sciences (IBG-2), 52425, Jülich, Germany
- Forschungszentrum Jülich GmbH, Institute of Bio- and Geosciences, Bioinformatics (IBG-4), 52425, Jülich, Germany
- Bioeconomy Science Center, c/o Forschungszentrum Jülich GmbH, 52425, Jülich, Germany
- Heinrich-Heine-University, Chair of Biological Data Science, 40225, Düsseldorf, Germany
| | - Alexandra Wormit
- Institute for Biology I, RWTH Aachen University, Worringer Weg 3, 52074, Aachen, Germany.
- Bioeconomy Science Center, c/o Forschungszentrum Jülich GmbH, 52425, Jülich, Germany.
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Zhang X, He Y, Li L, Liu H, Hong G. Involvement of the R2R3-MYB transcription factor MYB21 and its homologs in regulating flavonol accumulation in Arabidopsis stamen. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:4319-4332. [PMID: 33831169 PMCID: PMC8163065 DOI: 10.1093/jxb/erab156] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 04/03/2021] [Indexed: 05/19/2023]
Abstract
Commonly found flavonols in plants are synthesized from dihydroflavonols by flavonol synthase (FLS). The genome of Arabidopsis thaliana contains six FLS genes, among which FLS1 encodes a functional enzyme. Previous work has demonstrated that the R2R3-MYB subgroup 7 transcription factors MYB11, MYB12, and MYB111 redundantly regulate flavonol biosynthesis. However, flavonol accumulation in pollen grains was unaffected in the myb11myb12myb111 triple mutant. Here we show that MYB21 and its homologs MYB24 and MYB57, which belong to subgroup 19, promote flavonol biosynthesis through regulation of FLS1 gene expression. We used a combination of genetic and metabolite analysis to identify the role of MYB21 in regulating flavonol biosynthesis through direct binding to the GARE cis-element in the FLS1 promoter. Treatment with kaempferol or overexpression of FLS1 rescued stamen defects in the myb21 mutant. We also observed that excess reactive oxygen species (ROS) accumulated in the myb21 stamen, and that treatment with the ROS inhibitor diphenyleneiodonium chloride partly rescued the reduced fertility of the myb21 mutant. Furthermore, drought increased ROS abundance and impaired fertility in myb21, myb21myb24myb57, and chs, but not in the wild type or myb11myb12myb111, suggesting that pollen-specific flavonol accumulation contributes to drought-induced male fertility by ROS scavenging in Arabidopsis.
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Affiliation(s)
- Xueying Zhang
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Sciences, 198 Shiqiao Road, Hangzhou 310021, China
| | - Yuqing He
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Sciences, 198 Shiqiao Road, Hangzhou 310021, China
| | - Linying Li
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Sciences, 198 Shiqiao Road, Hangzhou 310021, China
| | - Hongru Liu
- National Key Laboratory of Plant Molecular Genetics and National Plant Gene Research Center, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Shanghai 200032, China
| | - Gaojie Hong
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Sciences, 198 Shiqiao Road, Hangzhou 310021, China
- Correspondence:
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Behr M, Neutelings G, El Jaziri M, Baucher M. You Want it Sweeter: How Glycosylation Affects Plant Response to Oxidative Stress. FRONTIERS IN PLANT SCIENCE 2020; 11:571399. [PMID: 33042189 PMCID: PMC7525049 DOI: 10.3389/fpls.2020.571399] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 09/01/2020] [Indexed: 05/02/2023]
Abstract
Oxidative stress is a cellular threat which puts at risk the productivity of most of crops valorized by humankind in terms of food, feed, biomaterial, or bioenergy. It is therefore of crucial importance to understand the mechanisms by which plants mitigate the deleterious effects of oxidizing agents. Glycosylation of antioxidant molecules and phytohormones modifies their chemical properties as well as their cellular and histological repartition. This review emphasizes the mechanisms and the outcomes of this conjugation reaction on plant ability to face growing conditions favoring oxidative stress, in mirror with the activity of deglycosylating enzymes. Pioneer evidence bridging flavonoid, glycosylation, and redox homeostasis paved the way for numerous functional analyses of UDP-glycosyltransferases (UGTs), such as the identification of their substrates and their role to circumvent oxidative stress resulting from various environmental challenges. (De)glycosylation appears as a simple chemical reaction regulating the biosynthesis and/or the activity of a myriad of specialized metabolites partaking in response to pathogen and abiotic stresses. This outcome underlies the possibility to valorize UGTs potential to upgrade plant adaptation and fitness in a rising context of sub-optimal growing conditions subsequent to climate change.
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Affiliation(s)
- Marc Behr
- Laboratoire de Biotechnologie Végétale, Université libre de Bruxelles, Gosselies, Belgium
| | - Godfrey Neutelings
- UGSF—Unité de Glycobiologie Structurale et Fonctionnelle, UMR 8576, Université de Lille, CNRS, Lille, France
| | - Mondher El Jaziri
- Laboratoire de Biotechnologie Végétale, Université libre de Bruxelles, Gosselies, Belgium
| | - Marie Baucher
- Laboratoire de Biotechnologie Végétale, Université libre de Bruxelles, Gosselies, Belgium
- *Correspondence: Marie Baucher,
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Campos L, López-Gresa MP, Fuertes D, Bellés JM, Rodrigo I, Lisón P. Tomato glycosyltransferase Twi1 plays a role in flavonoid glycosylation and defence against virus. BMC PLANT BIOLOGY 2019; 19:450. [PMID: 31655554 PMCID: PMC6815406 DOI: 10.1186/s12870-019-2063-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 10/09/2019] [Indexed: 05/05/2023]
Abstract
BACKGROUND Secondary metabolites play an important role in the plant defensive response. They are produced as a defence mechanism against biotic stress by providing plants with antimicrobial and antioxidant weapons. In higher plants, the majority of secondary metabolites accumulate as glycoconjugates. Glycosylation is one of the commonest modifications of secondary metabolites, and is carried out by enzymes called glycosyltransferases. RESULTS Here we provide evidence that the previously described tomato wound and pathogen-induced glycosyltransferase Twi1 displays in vitro activity toward the coumarins scopoletin, umbelliferone and esculetin, and the flavonoids quercetin and kaempferol, by uncovering a new role of this gene in plant glycosylation. To test its activity in vivo, Twi1-silenced transgenic tomato plants were generated and infected with Tomato spotted wilt virus. The Twi1-silenced plants showed a differential accumulation of Twi1 substrates and enhanced susceptibility to the virus. CONCLUSIONS Biochemical in vitro assays and transgenic plants generation proved to be useful strategies to assign a role of tomato Twi1 in the plant defence response. Twi1 glycosyltransferase showed to regulate quercetin and kaempferol levels in tomato plants, affecting plant resistance to viral infection.
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Affiliation(s)
- Laura Campos
- Instituto de Biología Molecular y Celular de Plantas, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas, Valencia, Spain
| | - María Pilar López-Gresa
- Instituto de Biología Molecular y Celular de Plantas, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas, Valencia, Spain
| | - Diana Fuertes
- Instituto de Biología Molecular y Celular de Plantas, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas, Valencia, Spain
| | - José María Bellés
- Instituto de Biología Molecular y Celular de Plantas, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas, Valencia, Spain
| | - Ismael Rodrigo
- Instituto de Biología Molecular y Celular de Plantas, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas, Valencia, Spain
| | - Purificación Lisón
- Instituto de Biología Molecular y Celular de Plantas, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas, Valencia, Spain
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Li X, Jin L, Pan X, Yang L, Guo W. Proteins expression and metabolite profile insight into phenolic biosynthesis during highbush blueberry fruit maturation. Food Chem 2019; 290:216-228. [PMID: 31000040 DOI: 10.1016/j.foodchem.2019.03.115] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 03/14/2019] [Accepted: 03/22/2019] [Indexed: 10/27/2022]
Abstract
Blueberry is one of the richest phenolic sources, providing health benefits. To study blueberry phenolic biosynthesis, we investigated phenolics and proteomics at three typical fruit maturation phases. Multiple isoforms of enzymes and multiple members of transcription factors involved in phenolic biosynthesis were divergent and differently regulated. Regulation of some proteins resulted in change of phenolic content. During fruit maturation, down-regulation of VcOMT (CUFF.177.1) and VcLAR2 (CUFF.16780.1) was associated with decreases of ferulic acid and catechin, respectively; Up-regulation of VcFLS (CUFF.41155.1), and VcF3'5'H (CUFF.51711.1) and VcF3'5'H (gene.g10884.t1.1) likely drove increases of their products (quercetin and myricetin); Up-regulation of VcUFGALT (CUFF.20951.1) and VcUFGT73 (4333_g.1) and down-regulation of VcU5GT (CUFF.51258.1) were correlated to accumulation of anthocyanins with 3-glucoside/galactoside. Additionally, four TFs, VcAPRR2 (CUFF.24826.1), VcbHLH3 (CUFF.37765.1), VcWD (CUFF.28282.2) and VcWD (CUFF.28273.1) were probably related to regulation of anthocyanin biosynthesis. These proteins were potential targets for genetic improvement in a breeding program.
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Affiliation(s)
- Xiaobai Li
- Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China.
| | - Liang Jin
- Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
| | - Xuhao Pan
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao 266101, China
| | - Li Yang
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, China
| | - Weidong Guo
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, China
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Optimization of Ultrasound-Assisted Extraction of Flavonoids from Olive ( Olea europaea) Leaves, and Evaluation of Their Antioxidant and Anticancer Activities. Molecules 2018; 23:molecules23102513. [PMID: 30274358 PMCID: PMC6222376 DOI: 10.3390/molecules23102513] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2018] [Revised: 09/29/2018] [Accepted: 09/29/2018] [Indexed: 11/17/2022] Open
Abstract
Olea europaea leaves are the major byproduct of olive farming. In this study, ultrasound-assisted extraction of flavonoids from olive leaves was optimized using response surface methodology, and the flavonoid compounds and their antioxidant and anticancer activities were investigated by high performance liquid chromatography. The results showed that the optimized conditions for achieving the maximum yield of flavonoids (74.95 mg RE/g dm) were 50 °C temperature, 270 W power, 50 min time, and 41 mL/g liquid-solid ratio. There was a significant difference in the total flavonoid content between the aged and young leaves harvested in April and July, and six main components were quantified. Among them, luteolin-4’-O-glucoside was the most predominant flavonoid compound, followed by apigenin-7-O-glucoside and rutin. Olive leaves also contained small amounts of luteolin, apigenin, and quercetin. Additionally, excellent antioxidant activity was exhibited when tested with the DPPH assay; superoxide radical-scavenging ability and reducing power was also tested. The anticancer activity of the flavonoids was assessed using HeLa cervical cancer cells, and it was observed that increasing concentrations of olive leaf flavonoids resulted in decreased cancer cell viability. These results suggest that the flavonoids from olive leaves could be used as a potential source of natural antioxidants for the pharmaceutical and food industries.
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Wang Q, Xu Y, Xu J, Wang X, Shen C, Zhang Y, Liu X, Yu B, Zhang J. Molecular cloning and expression of a glycosyltransferase from Bacillus subtilis for modification of morin and related polyphenols. Biotechnol Lett 2017; 39:1229-1235. [PMID: 28484911 DOI: 10.1007/s10529-017-2352-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 05/04/2017] [Indexed: 01/03/2023]
Abstract
OBJECTIVES To characterize glycosyltransferases from Bacillus subtilis ATCC 6633 and investigate their substrate specificity towards plant polyphenols. RESULTS Among the cloned and expressed six UDP-glycosyltransferases (BsGT1-6), BsGT-1 showed activity with a wide range of polyphenols: morin, quercetin, alizarin, rehin, curcumin and aloe emodin. The gene of BsGT-1 has an ORF of 1206 bp encoding 402 amino acids. The recombinant enzyme was purified to homogeneity by Ni-NTA affinity chromatograph, and its biochemical characteristics were identified by HPLC-UV/MS, 1H-NMR and 13C-NMR. BsGT-1 has an MW of approx. 46 kDa as indicated by SDS-PAGE; its activity was optimal at 40 °C and pH 8.5. The Km value of BsGT-1 towards morin was 110 μM. CONCLUSIONS BsGT-1 from B. subtilis was cloned. It had high catalytic capabilities towards polyphenols which would make it feasible for the structural modification of polyphenols.
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Affiliation(s)
- Qianqian Wang
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, 24# TongJia Xiang Street, Nanjing, 210009, Jiangsu, China.,Jiangsu Key Laboratory of TCM Evaluation and Translational Research, China Pharmaceutical University, Nanjing, 211198, Jiangsu, China
| | - Yixiang Xu
- Institute of Biotechnology for TCM Research, School of Traditional Chinese Medicine, China Pharmaceutical University, Nanjing, 210009, Jiangsu, China
| | - Jiaqi Xu
- Jiangsu Key Laboratory of TCM Evaluation and Translational Research, China Pharmaceutical University, Nanjing, 211198, Jiangsu, China
| | - Xudong Wang
- Institute of Biotechnology for TCM Research, School of Traditional Chinese Medicine, China Pharmaceutical University, Nanjing, 210009, Jiangsu, China
| | - Chen Shen
- Institute of Biotechnology for TCM Research, School of Traditional Chinese Medicine, China Pharmaceutical University, Nanjing, 210009, Jiangsu, China
| | - Yan Zhang
- Institute of Biotechnology for TCM Research, School of Traditional Chinese Medicine, China Pharmaceutical University, Nanjing, 210009, Jiangsu, China
| | - Xiufeng Liu
- Institute of Biotechnology for TCM Research, School of Traditional Chinese Medicine, China Pharmaceutical University, Nanjing, 210009, Jiangsu, China
| | - Boyang Yu
- Jiangsu Key Laboratory of TCM Evaluation and Translational Research, China Pharmaceutical University, Nanjing, 211198, Jiangsu, China
| | - Jian Zhang
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, 24# TongJia Xiang Street, Nanjing, 210009, Jiangsu, China. .,Institute of Biotechnology for TCM Research, School of Traditional Chinese Medicine, China Pharmaceutical University, Nanjing, 210009, Jiangsu, China.
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Ji A, Jia J, Xu Z, Li Y, Bi W, Ren F, He C, Liu J, Hu K, Song J. Transcriptome-Guided Mining of Genes Involved in Crocin Biosynthesis. FRONTIERS IN PLANT SCIENCE 2017; 8:518. [PMID: 28443112 PMCID: PMC5387100 DOI: 10.3389/fpls.2017.00518] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2016] [Accepted: 03/23/2017] [Indexed: 05/11/2023]
Abstract
Gardenia jasminoides is used in traditional Chinese medicine and has drawn attention as a rich source of crocin, a compound with reported activity against various cancers, depression and cardiovascular disease. However, genetic information on the crocin biosynthetic pathway of G. jasminoides is scarce. In this study, we performed a transcriptome analysis of the leaves, green fruits, and red fruits of G. jasminoides to identify and predict the genes that encode key enzymes responsible for crocin production, compared with Crocus sativus. Twenty-seven putative pathway genes were specifically expressed in the fruits, consistent with the distribution of crocin in G. jasminoides. Twenty-four of these genes were reported for the first time, and a novel CCD4a gene was predicted that encodes carotenoid cleavage dioxygenase leading to crocin synthesis, in contrast to CCD2 of C. sativus. In addition, 6 other candidate genes (ALDH12, ALDH14, UGT94U1, UGT86D1, UGT71H4, and UGT85K18) were predicted to be involved in crocin biosynthesis following phylogenetic analysis and different gene expression profiles. Identifying the genes that encode key enzymes should help elucidate the crocin biosynthesis pathway.
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Affiliation(s)
- Aijia Ji
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing, China
| | - Jing Jia
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing, China
| | - Zhichao Xu
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing, China
| | - Ying Li
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing, China
| | - Wu Bi
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing, China
| | - Fengming Ren
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing, China
- Chongqing Institute of Medicinal Plant CultivationChongqing, China
| | - Chunnian He
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing, China
| | - Jie Liu
- Chongqing Institute of Medicinal Plant CultivationChongqing, China
| | - Kaizhi Hu
- Chongqing Institute of Medicinal Plant CultivationChongqing, China
- *Correspondence: Kaizhi Hu
| | - Jingyuan Song
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing, China
- Chongqing Institute of Medicinal Plant CultivationChongqing, China
- Jingyuan Song
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Guo DD, Liu F, Tu YH, He BX, Gao Y, Guo ML. Expression Patterns of Three UGT Genes in Different Chemotype Safflower Lines and under MeJA Stimulus Revealed Their Potential Role in Flavonoid Biosynthesis. PLoS One 2016; 11:e0158159. [PMID: 27391785 PMCID: PMC4938162 DOI: 10.1371/journal.pone.0158159] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 06/10/2016] [Indexed: 12/16/2022] Open
Abstract
Safflower (Carthamus tinctorius L.) has received a significant amount of attention as a medicinal plant in China. Flavonoids are the dominant active medical compounds. UDP-glycosyltransferase plays an essential role in the biosynthesis and storage of flavonoids in safflower. In this study, 45 UGT unigenes were screened from our transcriptomic database of safflower. Among them, 27 UGT unigenes were predicted to own a complete open reading frame with various pI and Mw. The phylogenetic tree showed that CtUGT3 and CtUGT16 were classified under the UGT71 subfamily involved in metabolite process, whereas CtUGT25 has high identities with PoUGT both catalyzing the glycosylation of flavonoids and belonging to the UGT90 subfamily. cDNA microarray exhibited that the three UGT genes displayed temporal difference in two chemotype safflower lines. To functionally characterize UGT in safflower, CtUGT3, CtUGT16 and CtUGT25 were cloned and analyzed. Subcellular localization suggested that the three UGTs might be located in the cell cytoplasm and chloroplast. The expression pattern showed that the three UGTs were all suppressed in two lines responsive to methyl jasmonate induction. The co-expression relation of expression pattern and metabolite accumulation demonstrated that CtUGT3 and CtUGT25 were positively related to kaempferol-3-O-β-D-glucoside and CtUGT16 was positively related to quercetin-3-O-β-D-glucoside in yellow line, whereas CtUGT3 and CtUGT25 were positively related to quercetin-3-O-β-D-glucoside in white line. This study indicates that the three CtUGTs play a significant and multiple role in flavonoids biosynthesis with presenting different functional characterization in two safflower lines.
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Affiliation(s)
- Dan-Dan Guo
- Department of Pharmacognosy, College of Pharmacy, Second Military Medical University, 200433, Shanghai, China
| | - Fei Liu
- Department of Pharmacognosy, College of Pharmacy, Second Military Medical University, 200433, Shanghai, China
| | - Yan-Hua Tu
- Department of Pharmacognosy, College of Pharmacy, Second Military Medical University, 200433, Shanghai, China
| | - Bei-Xuan He
- Department of Pharmacognosy, College of Pharmacy, Second Military Medical University, 200433, Shanghai, China
| | - Yue Gao
- Department of Pharmacognosy, College of Pharmacy, Second Military Medical University, 200433, Shanghai, China
- * E-mail: (MLG); (YG)
| | - Mei-Li Guo
- Department of Pharmacognosy, College of Pharmacy, Second Military Medical University, 200433, Shanghai, China
- * E-mail: (MLG); (YG)
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Tiwari P, Sangwan RS, Sangwan NS. Plant secondary metabolism linked glycosyltransferases: An update on expanding knowledge and scopes. Biotechnol Adv 2016; 34:714-739. [PMID: 27131396 DOI: 10.1016/j.biotechadv.2016.03.006] [Citation(s) in RCA: 131] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Revised: 02/06/2016] [Accepted: 03/19/2016] [Indexed: 02/04/2023]
Abstract
The multigene family of enzymes known as glycosyltransferases or popularly known as GTs catalyze the addition of carbohydrate moiety to a variety of synthetic as well as natural compounds. Glycosylation of plant secondary metabolites is an emerging area of research in drug designing and development. The unsurpassing complexity and diversity among natural products arising due to glycosylation type of alterations including glycodiversification and glycorandomization are emerging as the promising approaches in pharmacological studies. While, some GTs with broad spectrum of substrate specificity are promising candidates for glycoengineering while others with stringent specificity pose limitations in accepting molecules and performing catalysis. With the rising trends in diseases and the efficacy/potential of natural products in their treatment, glycosylation of plant secondary metabolites constitutes a key mechanism in biogeneration of their glycoconjugates possessing medicinal properties. The present review highlights the role of glycosyltransferases in plant secondary metabolism with an overview of their identification strategies, catalytic mechanism and structural studies on plant GTs. Furthermore, the article discusses the biotechnological and biomedical application of GTs ranging from detoxification of xenobiotics and hormone homeostasis to the synthesis of glycoconjugates and crop engineering. The future directions in glycosyltransferase research should focus on the synthesis of bioactive glycoconjugates via metabolic engineering and manipulation of enzyme's active site leading to improved/desirable catalytic properties. The multiple advantages of glycosylation in plant secondary metabolomics highlight the increasing significance of the GTs, and in near future, the enzyme superfamily may serve as promising path for progress in expanding drug targets for pharmacophore discovery and development.
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Affiliation(s)
- Pragya Tiwari
- Department of Metabolic and Structural Biology, CSIR-Central Institute of Medicinal and Aromatic Plants (CSIR-CIMAP), P.O. CIMAP, Lucknow 226015, India
| | - Rajender Singh Sangwan
- Department of Metabolic and Structural Biology, CSIR-Central Institute of Medicinal and Aromatic Plants (CSIR-CIMAP), P.O. CIMAP, Lucknow 226015, India; Center of Innovative and Applied Bioprocessing (CIAB), A National Institute under Department of Biotechnology, Government of India, C-127, Phase-8, Industrial Area, S.A.S. Nagar, Mohali 160071, Punjab, India
| | - Neelam S Sangwan
- Department of Metabolic and Structural Biology, CSIR-Central Institute of Medicinal and Aromatic Plants (CSIR-CIMAP), P.O. CIMAP, Lucknow 226015, India.
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Liu J, Hou J, Jiang C, Li G, Lu H, Meng F, Shi L. Deep Sequencing of the Scutellaria baicalensis Georgi Transcriptome Reveals Flavonoid Biosynthetic Profiling and Organ-Specific Gene Expression. PLoS One 2015; 10:e0136397. [PMID: 26317778 PMCID: PMC4552754 DOI: 10.1371/journal.pone.0136397] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Accepted: 08/04/2015] [Indexed: 12/22/2022] Open
Abstract
Scutellaria baicalensis Georgi has long been used in traditional medicine to treat various such widely varying diseases and has been listed in the Chinese Pharmacopeia, the Japanese Pharmacopeia, the Korean Pharmacopoeia and the European Pharmacopoeia. Flavonoids, especially wogonin, wogonoside, baicalin, and baicalein, are its main functional ingredients with various pharmacological activities. Although pharmaological studies for these flavonoid components have been well conducted, the molecular mechanism of their biosynthesis remains unclear in S. baicalensis. In this study, Illumina/Solexa deep sequencing generated more than 91 million paired-end reads and 49,507 unigenes from S. baicalensis roots, stems, leaves and flowers. More than 70% unigenes were annotated in at least one of the five public databases and 13,627 unigenes were assigned to 3,810 KEGG genes involved in 579 different pathways. 54 unigenes that encode 12 key enzymes involved in the pathway of flavonoid biosynthesis were discovered. One baicalinase and three baicalein 7-O-glucuronosyltransferases genes potentially involved in the transformation between baicalin/wogonoside and baicalein/wogonin were identified. Four candidate 6-hydroxylase genes for the formation of baicalin/baicalein and one candidate 8-O-methyltransferase gene for the biosynthesis of wogonoside/wogonin were also recognized. Our results further support the conclusion that, in S. baicalensis, 3,5,7-trihydroxyflavone was the precursor of the four above compounds. Then, the differential expression models and simple sequence repeats associated with these genes were carefully analyzed. All of these results not only enrich the gene resource but also benefit research into the molecular genetics and functional genomics in S. baicalensis.
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Affiliation(s)
- Jinxin Liu
- Key Laboratory of Traditional Chinese Medicine Research and Development of Hebei Province, Institute of Traditional Chinese Medicine, Chengde Medical University, Chengde, 067000, China; Beijing Area Major Laboratory of Protection and Utilization of Traditional Chinese Medicine, Beijing Normal University, Beijing, 100875, China; State Key Laboratory Breeding Base of Dao-di Herbs, China Academy of Chinese Medical Sciences, Beijng, 100700, China
| | - Jingyi Hou
- Key Laboratory of Traditional Chinese Medicine Research and Development of Hebei Province, Institute of Traditional Chinese Medicine, Chengde Medical University, Chengde, 067000, China; Beijing Area Major Laboratory of Protection and Utilization of Traditional Chinese Medicine, Beijing Normal University, Beijing, 100875, China; State Key Laboratory Breeding Base of Dao-di Herbs, China Academy of Chinese Medical Sciences, Beijng, 100700, China
| | - Chao Jiang
- Beijing Area Major Laboratory of Protection and Utilization of Traditional Chinese Medicine, Beijing Normal University, Beijing, 100875, China; State Key Laboratory Breeding Base of Dao-di Herbs, China Academy of Chinese Medical Sciences, Beijng, 100700, China
| | - Geng Li
- Beijing Area Major Laboratory of Protection and Utilization of Traditional Chinese Medicine, Beijing Normal University, Beijing, 100875, China; State Key Laboratory Breeding Base of Dao-di Herbs, China Academy of Chinese Medical Sciences, Beijng, 100700, China
| | - Heng Lu
- Beijing Area Major Laboratory of Protection and Utilization of Traditional Chinese Medicine, Beijing Normal University, Beijing, 100875, China; State Key Laboratory Breeding Base of Dao-di Herbs, China Academy of Chinese Medical Sciences, Beijng, 100700, China
| | - Fanyun Meng
- Beijing Area Major Laboratory of Protection and Utilization of Traditional Chinese Medicine, Beijing Normal University, Beijing, 100875, China; State Key Laboratory Breeding Base of Dao-di Herbs, China Academy of Chinese Medical Sciences, Beijng, 100700, China
| | - Linchun Shi
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 100193, China
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Ruby, Santosh Kumar RJ, Vishwakarma RK, Singh S, Khan BM. Molecular cloning and characterization of genistein 4'-O-glucoside specific glycosyltransferase from Bacopa monniera. Mol Biol Rep 2014; 41:4675-88. [PMID: 24664316 DOI: 10.1007/s11033-014-3338-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2013] [Accepted: 03/18/2014] [Indexed: 11/29/2022]
Abstract
Health related benefits of isoflavones such as genistein are well known. Glycosylation of genistein yields different glycosides like genistein 7-O-glycoside (genistin) and genistein 4'-O-glycoside (sophoricoside). This is the first report on isolation, cloning and functional characterization of a glycosyltransferase specific for genistein 4'-O-glucoside from Bacopa monniera, an important Indian medicinal herb. The glycosyltransferase from B. monniera (UGT74W1) showed 49% identity at amino acid level with the glycosyltransferases from Lycium barbarum. The UGT74W1 sequence contained all the conserved motifs present in plant glycosyltransferases. UGT74W1 was cloned in pET-30b (+) expression vector and transformed into E. coli. The molecular mass of over expressed protein was found to be around 52 kDa. Functional characterization of the enzyme was performed using different substrates. Product analysis was done using LC-MS and HPLC, which confirmed its specificity for genistein 4'-O-glucoside. Immuno-localization studies of the UGT74W1 showed its localization in the vascular bundle. Spatio-temporal expression studies under normal and stressed conditions were also performed. The control B. monniera plant showed maximum expression of UGT74W1 in leaves followed by roots and stem. Salicylic acid treatment causes almost tenfold increase in UGT74W1 expression in roots, while leaves and stem showed decrease in expression. Since salicylic acid is generated at the time of injury or wound caused by pathogens, this increase in UGT74W1 expression under salicylic acid stress might point towards its role in defense mechanism.
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Affiliation(s)
- Ruby
- Plant Tissue Culture Division, National Chemical Laboratory, Dr. Homi Bhabha Road, Pune, 411008, Maharashtra, India
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13
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Buer CS, Kordbacheh F, Truong TT, Hocart CH, Djordjevic MA. Alteration of flavonoid accumulation patterns in transparent testa mutants disturbs auxin transport, gravity responses, and imparts long-term effects on root and shoot architecture. PLANTA 2013; 238:171-89. [PMID: 23624937 DOI: 10.1007/s00425-013-1883-3] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Accepted: 04/08/2013] [Indexed: 05/18/2023]
Abstract
Flavonoids have broad cross-kingdom biological activity. In Arabidopsis, flavonoid accumulation in specific tissues, notably the root elongation zone and root/shoot junction modulate auxin transport, affect root gravitropism, and influence overall plant architecture. The relative contribution made by aglycones and their glycosides remains undetermined, and the longer-term phenotypic effects of altered flavonoid accumulation are not fully assessed. We tested Arabidopsis thaliana mutants that accumulate different flavonoids to determine which flavonoids were causing these affects. Tandem mass spectrometry and in situ fluorescence localisation were used to determine the in vivo levels of aglycones in specific tissues of 11 transparent testa mutants. We measured rootward and shootward auxin transport, gravitropic responses, and identified the long-term changes to root and shoot architecture. Unexpected aglycone species accumulated in vivo in several flavonoid-pathway mutants, and lower aglycone levels occurred in transcription factor mutants. Mutants accumulating more quercetin and quercetin-glycosides changed the greatest in auxin transport, gravitropism, and aerial tissue growth. Early flavonoid-pathway mutants showed aberrant lateral root initiation patterns including clustered lateral root initiations at a single site. Transcription factor mutants had multiple phenotypes including shallow root systems. These results confirm that aglycones are present at very low levels, show that lateral root initiation is perturbed in early flavonoid-pathway mutants, and indicate that altered flavonoid accumulation affects multiple aspects of plant architecture.
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Affiliation(s)
- Charles S Buer
- Plant Sciences Division, Research School of Biology, College of Medicine, Biology, and Environment, The Australian National University, Linneaus Bldg #134, Linneaus Way, Canberra, ACT 0200, Australia
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14
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Veljanovski V, Constabel CP. Molecular cloning and biochemical characterization of two UDP-glycosyltransferases from poplar. PHYTOCHEMISTRY 2013; 91:148-57. [PMID: 23375153 DOI: 10.1016/j.phytochem.2012.12.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Revised: 11/16/2012] [Accepted: 12/21/2012] [Indexed: 05/26/2023]
Abstract
Two pathogen-induced uridine diphosphate glycosyltransferases (UGTs) identified previously via co-expression with induced proanthocyanidin (PA) synthesis in poplar were cloned and characterized. Phylogenetic analysis grouped both genes with other known flavonoid UGTs that act on flavonols and anthocyanins. Recombinant enzymes were produced in order to test if they could glycoslate flavonoids. PtUGT78L1 accepted the flavonols quercetin and kaempferol as well as cyanidin, and used UDP-galactose as a sugar donor. PtUGT78M1 did not accept any of the flavonoids tested as a substrate, but did transfer glucose from UDP-glucose to the universal substrate 2,4,6-trichlorophenol. However, neither enzyme acted on the flavan-3-ols catechin or epicatechin, intermediates in the PA biosynthetic pathway.
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Affiliation(s)
- Vasko Veljanovski
- Centre for Forest Biology and Department of Biology, University of Victoria, Victoria, BC, Canada
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15
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Singh S, Vishwakarma RK, Kumar RJS, Sonawane PD, Ruby, Khan BM. Functional Characterization of a Flavonoid Glycosyltransferase Gene from Withania somnifera (Ashwagandha). Appl Biochem Biotechnol 2013; 170:729-41. [DOI: 10.1007/s12010-013-0230-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2012] [Accepted: 04/07/2013] [Indexed: 11/28/2022]
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Sui X, Gao X, Ao M, Wang Q, Yang D, Wang M, Fu Y, Wang L. cDNA cloning and characterization of UDP-glucose: anthocyanidin 3-O-glucosyltransferase in Freesia hybrida. PLANT CELL REPORTS 2011; 30:1209-18. [PMID: 21318353 DOI: 10.1007/s00299-011-1029-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2010] [Revised: 01/18/2011] [Accepted: 01/20/2011] [Indexed: 05/07/2023]
Abstract
The enzyme that catalyzes the formation of the first stable anthocyanin in the biosynthesis of natural compounds is UDP-glucose: anthocyanidin 3-O-glucosyltransferase (UF3GT). A cDNA clone (Fh3GT1) encoding UF3GT was isolated from Freesia hybrida. Phylogenetic tree analysis indicated that Fh3GT1 was a novel member of glycosyltransferase, which was classified into monocot subgroups. Semi-quantitative RT-PCR analysis detected transcripts of Fh3GT1 in different organs of F. hybrida and in petals of Freesia cultivars of different colors, and the expression level reached the maximum at the fully opened stage of petals. Characterization of the enzymatic assays indicated that Fh3GT1 had a role in anthocyanin glycoside biosyntheses in vitro. To elucidate the function of Fh3GT1, RNA interference vector (pART-Fh3GT1i) was constructed, and introduced into Petunia grandiflora by Agrobacterium-mediated transformation. Integration of the Fh3GT1 in petunia genome was confirmed by PCR and Southern blotting. SqRT-PCR revealed that the endogenous Ph3GT1 mRNA expression levels decreased in transgenic lines compared with the wild-type. The content of total anthocyanin pigments also decreased with the reduction of mRNA transcript levels, and the transgenic petunia plants had significant changes on their flower colors. In summary, this work identified a UF3GT gene from Freesia hybrida and demonstrated a method to modify plant flower color by redirecting the anthocyanin biosynthesis.
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Affiliation(s)
- Xin Sui
- Key Laboratory of Molecular Epigenetics of Ministry of Education, Institute of Genetics and Cytology, Northeast Normal University, Changchun, People's Republic of China
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17
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He X, Blount JW, Ge S, Tang Y, Dixon RA. A genomic approach to isoflavone biosynthesis in kudzu (Pueraria lobata). PLANTA 2011; 233:843-55. [PMID: 21221632 DOI: 10.1007/s00425-010-1344-1] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Accepted: 12/22/2010] [Indexed: 05/18/2023]
Abstract
Roots of kudzu (Pueraria lobata) are a rich source of isoflavone O- and C-glycosides. Although O-glycosylation of (iso)flavonoids has been well characterized at the molecular level, no plant isoflavonoid C-glycosyltransferase genes have yet been isolated. To address the biosynthesis of kudzu isoflavonoids, we generated 6,365 high-quality expressed sequence tags (ESTs) from a subtraction cDNA library constructed using RNA from roots that differentially accumulate puerarin. The ESTs were clustered into 722 TCs and 3,913 singletons, from which 15 family I glycosyltransferases (UGTs) were identified. Hierarchical clustering analysis of the expression patterns of these UGTs with isoflavone synthase (IFS) in a range of tissues identified UGTs with potential functions in isoflavone glycosylation. The open reading frames of these UGTs were expressed in E. coli for functional analysis, and one was shown to preferentially glycosylate isoflavones at the 7-O-position. In addition, ESTs corresponding to chalcone synthase, chalcone reductase, chalcone isomerase (CHI) and 2-hydroxyisoflavanone dehydratase were identified. Recombinant CHI proteins had high activities with both 6'-deoxy- and 6'-hydroxy chalcones, typical of Type II CHIs. Establishment of this EST database and identification of genes associated with kudzu isoflavone biosynthesis and glycosylation provide a new resource for metabolic engineering of bioactive kudzu isoflavones.
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Affiliation(s)
- XianZhi He
- Plant Biology Division, Samuel Roberts Noble Foundation, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA
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18
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He F, Pan QH, Shi Y, Duan CQ. Biosynthesis and genetic regulation of proanthocyanidins in plants. Molecules 2008; 13:2674-703. [PMID: 18971863 PMCID: PMC6245171 DOI: 10.3390/molecules13102674] [Citation(s) in RCA: 114] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2008] [Revised: 10/21/2008] [Accepted: 10/23/2008] [Indexed: 01/15/2023] Open
Abstract
Proanthocyanidins (PAs), also known as condensed tannins, are a group of polyphenolic secondary metabolites synthesized in plants as oligomers or polymers of flavan-3-ol units via the flavonoid pathway. Due to their structural complexity and varied composition, only in the recent years has the study on the biosynthesis and regulation of PAs in plants taken off, although some details of the synthetic mechanism remain unclear. This paper aims to summarize the status of research on the structures of PAs in plants, the genes encoding key enzymes of biosynthetic pathway, the transport factors, the transcriptional regulation of PA biosynthesis and the genetic manipulation of PAs. The problems of this field were also discussed, including the nature of the final "enzyme" which catalyzes the polymerization reaction of PAs and the possible mechanism of how the elementary units of flavanols are assembled in vivo.
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Affiliation(s)
- Fei He
- Center for Viticulture and Enology, College of Food Science & Nutritional Engineering, China Agricultural University, Beijing, PR China.
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Hong BS, Kim JH, Kim NY, Kim BG, Chong YH, Ahn JH. Characterization of Uridine-Diphosphate Dependent Flavonoid Glucosyltransferase from Oryza sativa. BMB Rep 2007; 40:870-4. [DOI: 10.5483/bmbrep.2007.40.6.870] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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20
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Modolo LV, Blount JW, Achnine L, Naoumkina MA, Wang X, Dixon RA. A functional genomics approach to (iso)flavonoid glycosylation in the model legume Medicago truncatula. PLANT MOLECULAR BIOLOGY 2007; 64:499-518. [PMID: 17437063 DOI: 10.1007/s11103-007-9167-6] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2007] [Accepted: 03/21/2007] [Indexed: 05/14/2023]
Abstract
Analysis of over 200,000 expressed sequence tags from a range of Medicago truncatula cDNA libraries resulted in the identification of over 150 different family 1 glycosyltransferase (UGT) genes. Of these, 63 were represented by full length clones in an EST library collection. Among these, 19 gave soluble proteins when expressed in E. coli, and these were screened for catalytic activity against a range of flavonoid and isoflavonoid substrates using a high-throughput HPLC assay method. Eight UGTs were identified with activity against isoflavones, flavones, flavonols or anthocyanidins, and several showed high catalytic specificity for more than one class of (iso)flavonoid substrate. All tested UGTs preferred UDP-glucose as sugar donor. Phylogenetic analysis indicated that the Medicago (iso)flavonoid glycosyltransferase gene sequences fell into a number of different clades, and several clustered with UGTs annotated as glycosylating non-flavonoid substrates. Quantitative RT-PCR and DNA microarray analysis revealed unique transcript expression patterns for each of the eight UGTs in Medicago organs and cell suspension cultures, and comparison of these patterns with known phytochemical profiles suggested in vivo functions for several of the enzymes.
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Affiliation(s)
- Luzia V Modolo
- Plant Biology Division, Samuel Roberts Noble Foundation, Ardmore, OK 73401, USA
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