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Chen J, Zhang Y, Wei J, Hu X, Yin H, Liu W, Li D, Tian W, Hao Y, He Z, Fernie AR, Chen W. Beyond pathways: Accelerated flavonoids candidate identification and novel exploration of enzymatic properties using combined mapping populations of wheat. PLANT BIOTECHNOLOGY JOURNAL 2024; 22:2033-2050. [PMID: 38408119 PMCID: PMC11182594 DOI: 10.1111/pbi.14323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 02/06/2024] [Accepted: 02/12/2024] [Indexed: 02/28/2024]
Abstract
Although forward-genetics-metabolomics methods such as mGWAS and mQTL have proven effective in providing myriad loci affecting metabolite contents, they are somehow constrained by their respective constitutional flaws such as the hidden population structure for GWAS and insufficient recombinant rate for QTL. Here, the combination of mGWAS and mQTL was performed, conveying an improved statistical power to investigate the flavonoid pathways in common wheat. A total of 941 and 289 loci were, respectively, generated from mGWAS and mQTL, within which 13 of them were co-mapped using both approaches. Subsequently, the mGWAS or mQTL outputs alone and their combination were, respectively, utilized to delineate the metabolic routes. Using this approach, we identified two MYB transcription factor encoding genes and five structural genes, and the flavonoid pathway in wheat was accordingly updated. Moreover, we have discovered some rare-activity-exhibiting flavonoid glycosyl- and methyl-transferases, which may possess unique biological significance, and harnessing these novel catalytic capabilities provides potentially new breeding directions. Collectively, we propose our survey illustrates that the forward-genetics-metabolomics approaches including multiple populations with high density markers could be more frequently applied for delineating metabolic pathways in common wheat, which will ultimately contribute to metabolomics-assisted wheat crop improvement.
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Affiliation(s)
- Jie Chen
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan)Huazhong Agricultural UniversityWuhanChina
- Hubei Hongshan LaboratoryWuhanChina
- Yazhouwan National LaboratorySanyaChina
| | - Yueqi Zhang
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan)Huazhong Agricultural UniversityWuhanChina
- Hubei Hongshan LaboratoryWuhanChina
| | - Jiaqi Wei
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan)Huazhong Agricultural UniversityWuhanChina
- Hubei Hongshan LaboratoryWuhanChina
- Wuhan Academy of Agricultural SciencesWuhanChina
| | - Xin Hu
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan)Huazhong Agricultural UniversityWuhanChina
- Hubei Hongshan LaboratoryWuhanChina
| | - Huanran Yin
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan)Huazhong Agricultural UniversityWuhanChina
- Hubei Hongshan LaboratoryWuhanChina
| | - Wei Liu
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan)Huazhong Agricultural UniversityWuhanChina
- Hubei Hongshan LaboratoryWuhanChina
| | - Dongqin Li
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan)Huazhong Agricultural UniversityWuhanChina
| | - Wenfei Tian
- National Wheat Improvement Center, Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijingChina
| | - Yuanfeng Hao
- National Wheat Improvement Center, Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijingChina
| | - Zhonghu He
- National Wheat Improvement Center, Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijingChina
| | | | - Wei Chen
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan)Huazhong Agricultural UniversityWuhanChina
- Hubei Hongshan LaboratoryWuhanChina
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Yin B, Jia J, Sun X, Hu X, Ao M, Liu W, Tian Z, Liu H, Li D, Tian W, Hao Y, Xia X, Sade N, Brotman Y, Fernie AR, Chen J, He Z, Chen W. Dynamic metabolite QTL analyses provide novel biochemical insights into kernel development and nutritional quality improvement in common wheat. PLANT COMMUNICATIONS 2024; 5:100792. [PMID: 38173227 PMCID: PMC11121174 DOI: 10.1016/j.xplc.2024.100792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2023] [Revised: 12/20/2023] [Accepted: 01/01/2024] [Indexed: 01/05/2024]
Abstract
Despite recent advances in crop metabolomics, the genetic control and molecular basis of the wheat kernel metabolome at different developmental stages remain largely unknown. Here, we performed widely targeted metabolite profiling of kernels from three developmental stages (grain-filling kernels [FKs], mature kernels [MKs], and germinating kernels [GKs]) using a population of 159 recombinant inbred lines. We detected 625 annotated metabolites and mapped 3173, 3143, and 2644 metabolite quantitative trait loci (mQTLs) in FKs, MKs, and GKs, respectively. Only 52 mQTLs were mapped at all three stages, indicating the high stage specificity of the wheat kernel metabolome. Four candidate genes were functionally validated by in vitro enzymatic reactions and/or transgenic approaches in wheat, three of which mediated the tricin metabolic pathway. Metabolite flux efficiencies within the tricin pathway were evaluated, and superior candidate haplotypes were identified, comprehensively delineating the tricin metabolism pathway in wheat. Finally, additional wheat metabolic pathways were re-constructed by updating them to incorporate the 177 candidate genes identified in this study. Our work provides new information on variations in the wheat kernel metabolome and important molecular resources for improvement of wheat nutritional quality.
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Affiliation(s)
- Bo Yin
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China; Hubei Hongshan Laboratory, Wuhan 430070, China
| | - Jingqi Jia
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China; Hubei Hongshan Laboratory, Wuhan 430070, China
| | - Xu Sun
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China; Hubei Hongshan Laboratory, Wuhan 430070, China
| | - Xin Hu
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China; Hubei Hongshan Laboratory, Wuhan 430070, China
| | - Min Ao
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China; Hubei Hongshan Laboratory, Wuhan 430070, China
| | - Wei Liu
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China; Hubei Hongshan Laboratory, Wuhan 430070, China
| | - Zhitao Tian
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China; Hubei Hongshan Laboratory, Wuhan 430070, China
| | - Hongbo Liu
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China
| | - Dongqin Li
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China
| | - Wenfei Tian
- National Wheat Improvement Center, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yuanfeng Hao
- National Wheat Improvement Center, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xianchun Xia
- National Wheat Improvement Center, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Nir Sade
- School of Plant Sciences and Food Security, The Institute for Cereal Crops Improvement, Tel Aviv University, Tel Aviv 69978, Israel
| | - Yariv Brotman
- School of Plant Sciences and Food Security, The Institute for Cereal Crops Improvement, Tel Aviv University, Tel Aviv 69978, Israel
| | - Alisdair R Fernie
- Max Planck Institute of Molecular Plant Physiology, 14476 Potsdam-Golm, Germany
| | - Jie Chen
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China; Hubei Hongshan Laboratory, Wuhan 430070, China; Yazhouwan National Laboratory, Sanya 572025, China.
| | - Zhonghu He
- National Wheat Improvement Center, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.
| | - Wei Chen
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China; Hubei Hongshan Laboratory, Wuhan 430070, China.
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3
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Cui M, Lu A, Li J, Liu J, Fang Y, Pei T, Zhong X, Wei Y, Kong Y, Qiu W, Hu Y, Yang J, Chen X, Martin C, Zhao Q. Two types of O-methyltransferase are involved in biosynthesis of anticancer methoxylated 4'-deoxyflavones in Scutellaria baicalensis Georgi. PLANT BIOTECHNOLOGY JOURNAL 2022; 20:129-142. [PMID: 34490975 PMCID: PMC8710825 DOI: 10.1111/pbi.13700] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 08/24/2021] [Accepted: 08/27/2021] [Indexed: 05/05/2023]
Abstract
The medicinal plant Scutellaria baicalensis Georgi is rich in specialized 4'-deoxyflavones, which are reported to have many health-promoting properties. We assayed Scutellaria flavones with different methoxyl groups on human cancer cell lines and found that polymethoxylated 4'-deoxyflavones, like skullcapflavone I and tenaxin I have stronger ability to induce apoptosis compared to unmethylated baicalein, showing that methoxylation enhances bioactivity as well as the physical properties of specialized flavones, while having no side-effects on healthy cells. We investigated the formation of methoxylated flavones and found that two O-methyltransferase (OMT) families are active in the roots of S. baicalensis. The Type II OMTs, SbPFOMT2 and SbPFOMT5, decorate one of two adjacent hydroxyl groups on flavones and are responsible for methylation on the C6, 8 and 3'-hydroxyl positions, to form oroxylin A, tenaxin II and chrysoeriol respectively. The Type I OMTs, SbFOMT3, SbFOMT5 and SbFOMT6 account mainly for C7-methoxylation of flavones, but SbFOMT5 can also methylate baicalein on its C5 and C6-hydroxyl positions. The dimethoxylated flavone, skullcapflavone I (found naturally in roots of S. baicalensis) can be produced in yeast by co-expressing SbPFOMT5 plus SbFOMT6 when the appropriately hydroxylated 4'-deoxyflavone substrates are supplied in the medium. Co-expression of SbPFOMT5 plus SbFOMT5 in yeast produced tenaxin I, also found in Scutellaria roots. This work showed that both type I and type II OMT enzymes are involved in biosynthesis of methoxylated flavones in S. baicalensis.
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Affiliation(s)
- Meng‐Ying Cui
- Shanghai Key Laboratory of Plant Functional Genomics and ResourcesShanghai Chenshan Botanical GardenShanghai Chenshan Plant Science Research CenterChinese Academy of SciencesShanghaiChina
| | - An‐Rui Lu
- Shanghai Key Laboratory of Plant Functional Genomics and ResourcesShanghai Chenshan Botanical GardenShanghai Chenshan Plant Science Research CenterChinese Academy of SciencesShanghaiChina
- State Key Laboratory of Plant Molecular GeneticsCAS Center for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghaiChina
| | - Jian‐Xu Li
- State Key Laboratory of Plant Molecular GeneticsCAS Center for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghaiChina
| | - Jie Liu
- Shanghai Key Laboratory of Plant Functional Genomics and ResourcesShanghai Chenshan Botanical GardenShanghai Chenshan Plant Science Research CenterChinese Academy of SciencesShanghaiChina
| | - Yu‐Min Fang
- Shanghai Key Laboratory of Plant Functional Genomics and ResourcesShanghai Chenshan Botanical GardenShanghai Chenshan Plant Science Research CenterChinese Academy of SciencesShanghaiChina
| | - Tian‐Lin Pei
- Shanghai Key Laboratory of Plant Functional Genomics and ResourcesShanghai Chenshan Botanical GardenShanghai Chenshan Plant Science Research CenterChinese Academy of SciencesShanghaiChina
- State Key Laboratory of Plant Molecular GeneticsCAS Center for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghaiChina
| | - Xin Zhong
- Shanghai Key Laboratory of Plant Functional Genomics and ResourcesShanghai Chenshan Botanical GardenShanghai Chenshan Plant Science Research CenterChinese Academy of SciencesShanghaiChina
| | - Yu‐Kun Wei
- Shanghai Key Laboratory of Plant Functional Genomics and ResourcesShanghai Chenshan Botanical GardenShanghai Chenshan Plant Science Research CenterChinese Academy of SciencesShanghaiChina
| | - Yu Kong
- Shanghai Key Laboratory of Plant Functional Genomics and ResourcesShanghai Chenshan Botanical GardenShanghai Chenshan Plant Science Research CenterChinese Academy of SciencesShanghaiChina
| | - Wen‐Qing Qiu
- Key Laboratory of Metabolism and Molecular MedicineDepartment of Biochemistry and Molecular BiologySchool of Basic Medical SciencesFudan UniversityShanghaiChina
| | - Yong‐Hong Hu
- Shanghai Key Laboratory of Plant Functional Genomics and ResourcesShanghai Chenshan Botanical GardenShanghai Chenshan Plant Science Research CenterChinese Academy of SciencesShanghaiChina
| | - Jun Yang
- Shanghai Key Laboratory of Plant Functional Genomics and ResourcesShanghai Chenshan Botanical GardenShanghai Chenshan Plant Science Research CenterChinese Academy of SciencesShanghaiChina
- State Key Laboratory of Plant Molecular GeneticsCAS Center for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghaiChina
| | - Xiao‐Ya Chen
- Shanghai Key Laboratory of Plant Functional Genomics and ResourcesShanghai Chenshan Botanical GardenShanghai Chenshan Plant Science Research CenterChinese Academy of SciencesShanghaiChina
- State Key Laboratory of Plant Molecular GeneticsCAS Center for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghaiChina
| | - Cathie Martin
- Shanghai Key Laboratory of Plant Functional Genomics and ResourcesShanghai Chenshan Botanical GardenShanghai Chenshan Plant Science Research CenterChinese Academy of SciencesShanghaiChina
- John Innes CentreNorwichUK
| | - Qing Zhao
- Shanghai Key Laboratory of Plant Functional Genomics and ResourcesShanghai Chenshan Botanical GardenShanghai Chenshan Plant Science Research CenterChinese Academy of SciencesShanghaiChina
- State Key Laboratory of Plant Molecular GeneticsCAS Center for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghaiChina
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Lam PY, Lui ACW, Wang L, Liu H, Umezawa T, Tobimatsu Y, Lo C. Tricin Biosynthesis and Bioengineering. FRONTIERS IN PLANT SCIENCE 2021; 12:733198. [PMID: 34512707 PMCID: PMC8426635 DOI: 10.3389/fpls.2021.733198] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 07/28/2021] [Indexed: 05/23/2023]
Abstract
Tricin (3',5'-dimethoxyflavone) is a specialized metabolite which not only confers stress tolerance and involves in defense responses in plants but also represents a promising nutraceutical. Tricin-type metabolites are widely present as soluble tricin O-glycosides and tricin-oligolignols in all grass species examined, but only show patchy occurrences in unrelated lineages in dicots. More strikingly, tricin is a lignin monomer in grasses and several other angiosperm species, representing one of the "non-monolignol" lignin monomers identified in nature. The unique biological functions of tricin especially as a lignin monomer have driven the identification and characterization of tricin biosynthetic enzymes in the past decade. This review summarizes the current understanding of tricin biosynthetic pathway in grasses and tricin-accumulating dicots. The characterized and potential enzymes involved in tricin biosynthesis are highlighted along with discussion on the debatable and uncharacterized steps. Finally, current developments of bioengineering on manipulating tricin biosynthesis toward the generation of functional food as well as modifications of lignin for improving biorefinery applications are summarized.
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Affiliation(s)
- Pui Ying Lam
- Research Institute for Sustainable Humanosphere, Kyoto University, Kyoto, Japan
| | - Andy C. W. Lui
- School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Lanxiang Wang
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Hongjia Liu
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Toshiaki Umezawa
- Research Institute for Sustainable Humanosphere, Kyoto University, Kyoto, Japan
| | - Yuki Tobimatsu
- Research Institute for Sustainable Humanosphere, Kyoto University, Kyoto, Japan
| | - Clive Lo
- School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China
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Lin SJ, Yang YZ, Teng RM, Liu H, Li H, Zhuang J. Identification and expression analysis of caffeoyl-coenzyme A O-methyltransferase family genes related to lignin biosynthesis in tea plant (Camellia sinensis). PROTOPLASMA 2021; 258:115-127. [PMID: 32929631 DOI: 10.1007/s00709-020-01555-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2020] [Accepted: 09/02/2020] [Indexed: 05/09/2023]
Abstract
Tea plant, an economically important crop, is used in producing tea, which is a non-alcoholic beverage. Lignin, the second most abundant component of the cell wall, reduces the tenderness of tea leaves and affects tea quality. Caffeoyl-coenzyme A O-methyltransferase (CCoAOMT) involved in lignin biosynthesis affects the efficiency of lignin synthesis and lignin composition. A total of 10 CsCCoAOMTs were identified based on tea plant genome. Systematic analysis of CCoAOMTs was conducted for its physicochemical properties, phylogenetic relationships, conserved motifs, gene structure, and promoter cis-element prediction. Phylogenetic analysis suggested that all the CsCCoAOMT proteins can be categorized into three clades. The promoters of six CsCCoAOMT genes possessed lignin-specific cis-elements, indicating they are possibly essential for lignin biosynthesis. According to the distinct tempo-spatial expression profiles, five genes were substantially expressed in eight tested tissues. Most CsCCoAOMT genes were expressed in stems and leaves in three tea plant cultivars 'Longjing 43,' 'Anjibaicha,' and 'Fudingdabai' by RT-qPCR detection and analysis. The expression levels of two genes (CsCCoAOMT5 and CsCCoAOMT6) were higher than those of the other genes. The expression levels of most CsCCoAOMT genes in 'Longjing 43' were significantly higher than that those in 'Anjibaicha' and 'Fudingdabai.' Correlation analysis revealed that only the expression levels of CsCCoAOMT6 were positively correlated with lignin content in the leaves and stems. These results lay a foundation for the future exploration of the roles of CsCCoAOMTs in lignin biosynthesis in tea plant.
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Affiliation(s)
- Shi-Jia Lin
- Tea Science Research Institute, College of Horticulture, Nanjing Agricultural University, 1 Weigang, 210095, Nanjing, People's Republic of China
| | - Ya-Zhuo Yang
- Tea Science Research Institute, College of Horticulture, Nanjing Agricultural University, 1 Weigang, 210095, Nanjing, People's Republic of China
| | - Rui-Min Teng
- Tea Science Research Institute, College of Horticulture, Nanjing Agricultural University, 1 Weigang, 210095, Nanjing, People's Republic of China
| | - Hao Liu
- Tea Science Research Institute, College of Horticulture, Nanjing Agricultural University, 1 Weigang, 210095, Nanjing, People's Republic of China
| | - Hui Li
- Tea Science Research Institute, College of Horticulture, Nanjing Agricultural University, 1 Weigang, 210095, Nanjing, People's Republic of China
| | - Jing Zhuang
- Tea Science Research Institute, College of Horticulture, Nanjing Agricultural University, 1 Weigang, 210095, Nanjing, People's Republic of China.
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Uchida K, Sawada Y, Ochiai K, Sato M, Inaba J, Hirai MY. Identification of a Unique Type of Isoflavone O-Methyltransferase, GmIOMT1, Based on Multi-Omics Analysis of Soybean under Biotic Stress. PLANT & CELL PHYSIOLOGY 2020; 61:1974-1985. [PMID: 32894761 PMCID: PMC7758036 DOI: 10.1093/pcp/pcaa112] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 08/25/2020] [Indexed: 05/15/2023]
Abstract
Isoflavonoids are commonly found in leguminous plants. Glycitein is one of the isoflavones produced by soybean. The genes encoding the enzymes in the isoflavone biosynthetic pathway have mostly been identified and characterized. However, the gene(s) for isoflavone O-methyltransferase (IOMT), which catalyzes the last step of glycitein biosynthesis, has not yet been identified. In this study, we conducted multi-omics analyses of fungal-inoculated soybean and indicated that glycitein biosynthesis was induced in response to biotic stress. Moreover, we identified a unique type of IOMT, which participates in glycitein biosynthesis. Soybean seedlings were inoculated with Aspergillus oryzae or Rhizopus oligosporus and sampled daily for 8 d. Multi-omics analyses were conducted using liquid chromatography-tandem mass spectrometry and RNA sequencing. Metabolome analysis revealed that glycitein derivatives increased following fungal inoculation. Transcriptome co-expression analysis identified two candidate IOMTs that were co-expressed with the gene encoding flavonoid 6-hydroxylase (F6H), the key enzyme in glycitein biosynthesis. The enzymatic assay of the two IOMTs using respective recombinant proteins showed that one IOMT, named as GmIOMT1, produced glycitein. Unlike other IOMTs, GmIOMT1 belongs to the cation-dependent OMT family and exhibited the highest activity with Zn2+ among cations tested. Moreover, we demonstrated that GmIOMT1 overexpression increased the levels of glycitein derivatives in soybean hairy roots when F6H was co-expressed. These results strongly suggest that GmIOMT1 participates in inducing glycitein biosynthesis in response to biotic stress.
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Affiliation(s)
- Kai Uchida
- RIKEN Center for Sustainable Resource Science, Yokohama, 230-0045 Japan
| | - Yuji Sawada
- RIKEN Center for Sustainable Resource Science, Yokohama, 230-0045 Japan
| | | | - Muneo Sato
- RIKEN Center for Sustainable Resource Science, Yokohama, 230-0045 Japan
| | - Jun Inaba
- RIKEN Center for Sustainable Resource Science, Yokohama, 230-0045 Japan
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Liu X, Zhao C, Gong Q, Wang Y, Cao J, Li X, Grierson D, Sun C. Characterization of a caffeoyl-CoA O-methyltransferase-like enzyme involved in biosynthesis of polymethoxylated flavones in Citrus reticulata. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:3066-3079. [PMID: 32182355 PMCID: PMC7475179 DOI: 10.1093/jxb/eraa083] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 02/16/2020] [Indexed: 05/07/2023]
Abstract
Polymethoxylated flavones (PMFs), which accumulate exclusively in fruit peel of citrus, play important physiological and pharmacological roles but the genetic basis for the methylation of flavonoids has not been fully elucidated in citrus. Here we characterize a caffeoyl-CoA O-methyltransferase-like enzyme, designated CrOMT1. The expression pattern of CrOMT1 was highly correlated with the concentration of the three major PMFs in two different citrus fruit tissues during fruit maturation. Exposure of fruit to UV-B radiation sharply increased the level of CrOMT1 transcripts and also led to the accumulation of three PMFs. The potential role of CrOMT1 was studied by testing the catalytic activity of recombinant CrOMT1 with numerous possible substrates in vitro. The enzyme could most efficiently methylate flavones with neighboring hydroxy moieties, with high catalytic efficiencies found with 6-OH- and 8-OH-containing compounds, preferences that correspond precisely with the essential methylation sites involved in the synthesis of the three naturally occurring PMFs in Citrus reticulata. This indicates that CrOMT1 is capable of in vitro methylation reactions required to synthesize PMFs in vivo. Furthermore, transient overexpression of CrOMT1 increased levels of the three major PMFs in fruit, indicating that CrOMT1 is likely to play an essential role in the biosynthesis of PMFs in citrus.
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Affiliation(s)
- Xiaojuan Liu
- College of Agriculture & Biotechnology, Zhejiang University, Hangzhou, People’s Republic of China
| | - Chenning Zhao
- College of Agriculture & Biotechnology, Zhejiang University, Hangzhou, People’s Republic of China
| | - Qin Gong
- College of Agriculture & Biotechnology, Zhejiang University, Hangzhou, People’s Republic of China
| | - Yue Wang
- College of Agriculture & Biotechnology, Zhejiang University, Hangzhou, People’s Republic of China
| | - Jinping Cao
- College of Agriculture & Biotechnology, Zhejiang University, Hangzhou, People’s Republic of China
| | - Xian Li
- College of Agriculture & Biotechnology, Zhejiang University, Hangzhou, People’s Republic of China
- Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Hangzhou, People’s Republic of China
- The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, Hangzhou, People’s Republic of China
| | - Donald Grierson
- College of Agriculture & Biotechnology, Zhejiang University, Hangzhou, People’s Republic of China
- Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, Loughborough, UK
| | - Chongde Sun
- College of Agriculture & Biotechnology, Zhejiang University, Hangzhou, People’s Republic of China
- Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Hangzhou, People’s Republic of China
- The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, Hangzhou, People’s Republic of China
- Correspondence:
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Liu X, Wang Y, Chen Y, Xu S, Gong Q, Zhao C, Cao J, Sun C. Characterization of a Flavonoid 3'/5'/7- O-Methyltransferase from Citrus reticulata and Evaluation of the In Vitro Cytotoxicity of Its Methylated Products. Molecules 2020; 25:molecules25040858. [PMID: 32075249 PMCID: PMC7070609 DOI: 10.3390/molecules25040858] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Revised: 02/09/2020] [Accepted: 02/12/2020] [Indexed: 11/24/2022] Open
Abstract
O-methylation of flavonoids is an important modification reaction that occurs in plants. O-methylation contributes to the structural diversity of flavonoids, which have several biological and pharmacological functions. In this study, an O-methyltransferase gene (CrOMT2) was isolated from the fruit peel of Citrus reticulata, which encoding a multifunctional O-methyltransferase and could effectively catalyze the methylation of 3’-, 5’-, and 7-OH of flavonoids with vicinal hydroxyl substitutions. Substrate preference assays indicated that this recombinant enzyme favored polymethoxylated flavones (PMF)-type substrates in vitro, thereby providing biochemical evidence for the potential role of the enzyme in plants. Additionally, the cytotoxicity of the methylated products from the enzymatic catalytic reaction was evaluated in vitro using human gastric cell lines SGC-7901 and BGC-823. The results showed that the in vitro cytotoxicity of the flavonoids with the unsaturated C2-C3 bond was increased after being methylated at position 3’. These combined results provide biochemical insight regarding CrOMT2 in vitro and indicate the in vitro cytotoxicity of the products methylated by its catalytic reaction.
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Affiliation(s)
- Xiaojuan Liu
- College of Agriculture & Biotechnology, Zhejiang University, Zijingang Campus, Hangzhou 310058, China; (X.L.); (Y.W.); (Y.C.); (S.X.); (Q.G.); (C.Z.); (J.C.)
- Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Zijingang Campus, Hangzhou 310058, China
- The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, Zijingang Campus, Hangzhou 310058, China
| | - Yue Wang
- College of Agriculture & Biotechnology, Zhejiang University, Zijingang Campus, Hangzhou 310058, China; (X.L.); (Y.W.); (Y.C.); (S.X.); (Q.G.); (C.Z.); (J.C.)
- Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Zijingang Campus, Hangzhou 310058, China
- The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, Zijingang Campus, Hangzhou 310058, China
| | - Yezhi Chen
- College of Agriculture & Biotechnology, Zhejiang University, Zijingang Campus, Hangzhou 310058, China; (X.L.); (Y.W.); (Y.C.); (S.X.); (Q.G.); (C.Z.); (J.C.)
- Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Zijingang Campus, Hangzhou 310058, China
- The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, Zijingang Campus, Hangzhou 310058, China
| | - Shuting Xu
- College of Agriculture & Biotechnology, Zhejiang University, Zijingang Campus, Hangzhou 310058, China; (X.L.); (Y.W.); (Y.C.); (S.X.); (Q.G.); (C.Z.); (J.C.)
- Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Zijingang Campus, Hangzhou 310058, China
- The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, Zijingang Campus, Hangzhou 310058, China
| | - Qin Gong
- College of Agriculture & Biotechnology, Zhejiang University, Zijingang Campus, Hangzhou 310058, China; (X.L.); (Y.W.); (Y.C.); (S.X.); (Q.G.); (C.Z.); (J.C.)
- Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Zijingang Campus, Hangzhou 310058, China
- The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, Zijingang Campus, Hangzhou 310058, China
| | - Chenning Zhao
- College of Agriculture & Biotechnology, Zhejiang University, Zijingang Campus, Hangzhou 310058, China; (X.L.); (Y.W.); (Y.C.); (S.X.); (Q.G.); (C.Z.); (J.C.)
- Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Zijingang Campus, Hangzhou 310058, China
- The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, Zijingang Campus, Hangzhou 310058, China
| | - Jinping Cao
- College of Agriculture & Biotechnology, Zhejiang University, Zijingang Campus, Hangzhou 310058, China; (X.L.); (Y.W.); (Y.C.); (S.X.); (Q.G.); (C.Z.); (J.C.)
- Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Zijingang Campus, Hangzhou 310058, China
- The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, Zijingang Campus, Hangzhou 310058, China
| | - Chongde Sun
- College of Agriculture & Biotechnology, Zhejiang University, Zijingang Campus, Hangzhou 310058, China; (X.L.); (Y.W.); (Y.C.); (S.X.); (Q.G.); (C.Z.); (J.C.)
- Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Zijingang Campus, Hangzhou 310058, China
- The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, Zijingang Campus, Hangzhou 310058, China
- Correspondence: ; Tel.: +86-0571-8898-2229
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9
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Zhang XS, Ni R, Wang PY, Zhu TT, Sun CJ, Lou HX, Cheng AX. Isolation and functional characterization of two Caffeoyl Coenzyme A 3-O-methyltransferases from the fern species Polypodiodes amoena. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2019; 136:169-177. [PMID: 30685696 DOI: 10.1016/j.plaphy.2019.01.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Revised: 01/16/2019] [Accepted: 01/16/2019] [Indexed: 06/09/2023]
Abstract
Caffeoyl Coenzyme A 3-O-methyltransferases (CCoAOMTs) catalyze the transfer of a methyl group from S-adenosylmethionine (SAM) to a hydroxyl moiety. CCoAOMTs are important for the synthesis of lignin, which provides much of the rigidity required by tracheophytes to enable the long distance transport of water. So far, no CCoAOMTs has been characterized from the ancient tracheophytes ferns. Here, two genes, each encoding a CCoAOMT (and hence denoted PaCCoAOMT1 and PaCCoAOMT2), were isolated from the fern species Polypodiodes amoena. Sequence comparisons confirmed that the product of each gene resembled enzymes known to be associated with lignin synthesis in higher plants. When either of the genes was heterologously expressed in E. coli, the resulting recombinant protein was able to methylate caffeoyl CoA, along with a number of phenylpropanoids, flavones and flavonols containing two vicinal hydroxyl groups. Their in vitro conversion rate when presented with either caffeoyl CoA or certain flavonoids as substrate was comparable with that of the Medicago sativa MsCCoAOMT. Their constitutive expression in Arabidopsis thaliana boosted the plants' lignin content, but did not affect that of methylated flavonols, indicating that both PaCCoAOMTs contributed to lignin synthesis and that neither was able to methylate flavonols in planta. The transient expression of a PaCCoAOMT-GFP fusion gene in tobacco demonstrated that in planta, PaCCoAOMTs are likely directed to the cytoplasm.
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Affiliation(s)
- Xiao-Shuang Zhang
- Key Laboratory of Chemical Biology of Natural Products, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, Jinan, 250012, China
| | - Rong Ni
- Key Laboratory of Chemical Biology of Natural Products, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, Jinan, 250012, China
| | - Piao-Yi Wang
- Key Laboratory of Chemical Biology of Natural Products, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, Jinan, 250012, China
| | - Ting-Ting Zhu
- Key Laboratory of Chemical Biology of Natural Products, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, Jinan, 250012, China
| | - Chun-Jing Sun
- Key Laboratory of Chemical Biology of Natural Products, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, Jinan, 250012, China
| | - Hong-Xiang Lou
- Key Laboratory of Chemical Biology of Natural Products, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, Jinan, 250012, China
| | - Ai-Xia Cheng
- Key Laboratory of Chemical Biology of Natural Products, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, Jinan, 250012, China.
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10
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Poulev A, Heckman JR, Raskin I, Belanger FC. Tricin levels and expression of flavonoid biosynthetic genes in developing grains of purple and brown pericarp rice. PeerJ 2019; 7:e6477. [PMID: 30805251 PMCID: PMC6383554 DOI: 10.7717/peerj.6477] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 01/18/2019] [Indexed: 11/20/2022] Open
Abstract
The methylated flavone tricin has been associated with numerous health benefits, including reductions in intestinal and colon cancers in animal models. Tricin is found in a wide range of plant species and in many different tissues. However, whole cereal grains, such as rice, barley, oats, and wheat, are the only food sources of tricin, which is located in the bran portion of the grain. Variation in tricin levels was found in bran from rice genotypes with light brown, brown, red, and purple pericarp color, with the purple pericarp genotypes having the highest levels of tricin. Here, we analyzed tricin and tricin derivative levels in developing pericarp and embryo samples of a purple pericarp genotype, IAC600, that had high tricin and tricin derivative levels in the bran, and a light brown pericarp genotype, Cocodrie, that had no detectable tricin or tricin derivatives in the bran. Tricin and tricin derivatives were detected in both the pericarp and embryo of IAC600 but only in the embryo of Cocodrie. The purple pericarp rice had higher total levels of free tricin plus tricin derivatives than the light brown pericarp rice. When expressed on a per grain basis, most of the tricin component of IAC600 was in the pericarp. In contrast, Cocodrie had no detectable tricin in the pericarp samples but did have detectable chrysoeriol, a precursor of tricin, in the pericarp samples. We also used RNA-Seq analysis of developing pericarp and embryo samples of the two cultivars to compare the expression of genes involved in the flavonoid biosynthetic pathway. The results presented here suggest that understanding the basis of tricin accumulation in rice pericarp may lead to an approach to increasing tricin levels in whole grain rice. From analysis of gene expression levels in the pericarp samples it appears that regulation of the flavone specific genes is independent of regulation of the anthocyanin biosynthetic genes. It therefore may be feasible to develop brown pericarp rice cultivars that accumulate tricin in the pericarp.
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Affiliation(s)
- Alexander Poulev
- Department of Plant Biology, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
| | - Joseph R Heckman
- Department of Plant Biology, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
| | - Ilya Raskin
- Department of Plant Biology, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
| | - Faith C Belanger
- Department of Plant Biology, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
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11
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Sun B, Wang P, Wang R, Li Y, Xu S. Molecular Cloning and Characterization of a meta/ para- O-Methyltransferase from Lycoris aurea. Int J Mol Sci 2018; 19:ijms19071911. [PMID: 29966257 PMCID: PMC6073595 DOI: 10.3390/ijms19071911] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 06/05/2018] [Accepted: 06/28/2018] [Indexed: 11/16/2022] Open
Abstract
O-methyltransferases (OMTs) have been demonstrated to play key roles in the biosynthesis of plant secondary metabolites, such as alkaloids, isoprenoids, and phenolic compounds. Here, we isolated and characterized an OMT gene from Lycoris aurea (namely LaOMT1), based on our previous transcriptome sequencing data. Sequence alignment and phylogenetic analysis showed that LaOMT1 belongs to the class I OMT, and shares high identity to other known plant OMTs. Also, LaOMT1 is highly identical in its amino acid sequence to NpN4OMT, a norbelladine 4′-OMT from Narcissus sp. aff. pseudonarcissus involved in the biosynthesis of Amaryllidaceae alkaloids. Biochemical analysis indicated that the recombinant LaOMT1 displayed both para and metaO-methylation activities with caffeic acid and 3,4-dihydroxybenzaldehyde, and showed a strong preference for the meta position. Besides, LaOMT1 also catalyzes the O-methylation of norbelladine to form 4′-O-methylnorbelladine, which has been demonstrated to be a universal precursor of all the primary Amaryllidaceae alkaloid skeletons. The results from quantitative real-time PCR assay indicated that LaOMT1 was ubiquitously expressed in different tissues of L. aurea, and its highest expression level was observed in the ovary. Meanwhile, the largest concentration of lycorine and galanthamine were found in the ovary, whereas the highest level of narciclasine was observed in the bulb. In addition, sodium chloride (NaCl), cold, polyethylene glycol (PEG), sodium nitroprusside (SNP), and methyl jasmonate (MeJA) treatments could significantly increase LaOMT1 transcripts, while abscisic acid (ABA) treatment dramatically decreased the expression level of LaOMT1. Subcellular localization showed that LaOMT1 is mainly localized in cytoplasm and endosome. Our results in this study indicate that LaOMT1 may play a multifunctional role, and lay the foundation for Amaryllidaceae alkaloid biosynthesis in L. aurea.
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Affiliation(s)
- Bin Sun
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Nanjing 210014, China.
| | - Peng Wang
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Nanjing 210014, China.
| | - Ren Wang
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Nanjing 210014, China.
- The Jiangsu Provincial Platform for Conservation and Utilization of Agricultural Gerplasm, Nanjing 210014, China.
| | - Yikui Li
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Nanjing 210014, China.
- The Jiangsu Provincial Platform for Conservation and Utilization of Agricultural Gerplasm, Nanjing 210014, China.
| | - Sheng Xu
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Nanjing 210014, China.
- The Jiangsu Provincial Platform for Conservation and Utilization of Agricultural Gerplasm, Nanjing 210014, China.
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12
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Rakoczy M, Femiak I, Alejska M, Figlerowicz M, Podkowinski J. Sorghum CCoAOMT and CCoAOMT-like gene evolution, structure, expression and the role of conserved amino acids in protein activity. Mol Genet Genomics 2018; 293:1077-1089. [PMID: 29721721 PMCID: PMC6153501 DOI: 10.1007/s00438-018-1441-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Accepted: 04/24/2018] [Indexed: 11/28/2022]
Abstract
Sorghum is a crop plant that is grown for seeds, sucrose, forage and biofuel production. In all these applications, lignin is a superfluous component that decreases the efficiency of technological processes. Caffeoyl-coenzyme A O-methyltransferase (CCoAOMT) is an enzyme involved in monolignol synthesis that affects the efficiency of lignification and lignin composition. The sorghum genome harbors one CCoAOMT gene and six closely related CCoAOMT-like genes. The structures of four sorghum CCoAOMT-like enzymes suggest that these proteins might methylate caffeoyl coenzyme A and contribute to monolignol synthesis. In this study, two sorghum genes, CCoAOMT and one CCoAOMT-like, were found to be highly expressed in leaves, stems and immature seeds. The promoters of these genes possess clusters of transcription factor-binding sites specific for lignification, and this suggests that they are important for lignification. Phylogenetic analysis revealed that one sorghum CCoAOMT-like enzyme is closely related to ancestral cyanobacterial CCoAOMT-like proteins. The remaining CCoAOMT-like enzymes, including the one highly expressed in the leaves and stem, are closely related to CCoAOMT. Genes from these two groups possess different, evolutionarily conserved gene structures. The structure of the sorghum CCoAOMT-like protein from the ancestral clade was modeled and differences between enzymes from the two clades were analyzed. These results facilitate a better understanding of the evolution of genes involved in lignification, and provide valuable data for sorghum improvement through traditional breeding or molecular genetic techniques. The findings suggest that CCoAOMT-like genes might be recruited in lignification and raise questions of the frequency of such functional shifts.
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Affiliation(s)
- M Rakoczy
- Institute of Bioorganic Chemistry PAS, ul. Noskowskiego 12/14, 61-704, Poznan, Poland
| | - I Femiak
- Institute of Bioorganic Chemistry PAS, ul. Noskowskiego 12/14, 61-704, Poznan, Poland
| | - M Alejska
- Institute of Bioorganic Chemistry PAS, ul. Noskowskiego 12/14, 61-704, Poznan, Poland
| | - M Figlerowicz
- Institute of Bioorganic Chemistry PAS, ul. Noskowskiego 12/14, 61-704, Poznan, Poland
| | - J Podkowinski
- Institute of Bioorganic Chemistry PAS, ul. Noskowskiego 12/14, 61-704, Poznan, Poland.
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13
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Lee K, Choi GH, Back K. Cadmium-induced melatonin synthesis in rice requires light, hydrogen peroxide, and nitric oxide: Key regulatory roles for tryptophan decarboxylase and caffeic acid O-methyltransferase. J Pineal Res 2017; 63. [PMID: 28793366 DOI: 10.1111/jpi.12441] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 08/04/2017] [Indexed: 12/21/2022]
Abstract
In plants, melatonin production is induced by stimuli such as cold and drought, and cadmium (Cd) is the best elicitor of melatonin production in rice. However, the mechanism by which Cd induces melatonin synthesis in plants remains unknown. We challenged rice seedlings with Cd under different light conditions and found that continuous light produced the highest levels of melatonin, while continuous dark failed to induce melatonin production. Transcriptional and translational induction of tryptophan decarboxylase contributed to the light induction of melatonin during Cd treatment, whereas the protein level of light-induced caffeic acid O-methyltransferase (COMT) was decreased by Cd treatment. In analogy, COMT enzyme activity was inhibited in vitro by Cd in a dose-dependent manner. Notably, the Cd-induced melatonin synthesis was significantly impaired by treatment with either an H2 O2 production inhibitor (DPI) or an NO scavenger (cPTIO). The combination of both inhibitors almost completely abolished Cd-induced melatonin synthesis, suggesting an absolute requirement for H2 O2 and NO. However, neither serotonin nor N-acetylserotonin (NAS) was induced by H2 O2 alone. In contrast, NO significantly induced serotonin production but not NAS or melatonin production. This indicated that serotonin did not enter chloroplasts, where serotonin N-acetyltransferase (SNAT) is constitutively expressed. This suggests that chloroplastidic SNAT expression prevents increased melatonin production after exposure to stress, ultimately leading to the maintenance of a steady-state melatonin level inside cells.
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Affiliation(s)
- Kyungjin Lee
- Department of Biotechnology, Bioenergy Research Center, Chonnam National University, Gwangju, Korea
| | - Geun-Hee Choi
- Department of Biotechnology, Bioenergy Research Center, Chonnam National University, Gwangju, Korea
| | - Kyoungwhan Back
- Department of Biotechnology, Bioenergy Research Center, Chonnam National University, Gwangju, Korea
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14
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Jiang N, Doseff AI, Grotewold E. Flavones: From Biosynthesis to Health Benefits. PLANTS (BASEL, SWITZERLAND) 2016; 5:E27. [PMID: 27338492 PMCID: PMC4931407 DOI: 10.3390/plants5020027] [Citation(s) in RCA: 149] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 06/15/2016] [Accepted: 06/16/2016] [Indexed: 12/20/2022]
Abstract
Flavones correspond to a flavonoid subgroup that is widely distributed in the plants, and which can be synthesized by different pathways, depending on whether they contain C- or O-glycosylation and hydroxylated B-ring. Flavones are emerging as very important specialized metabolites involved in plant signaling and defense, as well as key ingredients of the human diet, with significant health benefits. Here, we appraise flavone formation in plants, emphasizing the emerging theme that biosynthesis pathway determines flavone chemistry. Additionally, we briefly review the biological activities of flavones, both from the perspective of the functions that they play in biotic and abiotic plant interactions, as well as their roles as nutraceutical components of the human and animal diet.
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Affiliation(s)
- Nan Jiang
- Center for Applied Plant Sciences, The Ohio State University, Columbus, OH 43210, USA.
- Department of Molecular Genetics, The Ohio State University, Columbus, OH 43210, USA.
| | - Andrea I Doseff
- Department of Molecular Genetics, The Ohio State University, Columbus, OH 43210, USA.
- Department of Physiology and Cell Biology, 305B Heart and Lung Research Institute, The Ohio State University, Columbus, OH 43210, USA.
| | - Erich Grotewold
- Center for Applied Plant Sciences, The Ohio State University, Columbus, OH 43210, USA.
- Department of Molecular Genetics, The Ohio State University, Columbus, OH 43210, USA.
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15
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Giordano D, Provenzano S, Ferrandino A, Vitali M, Pagliarani C, Roman F, Cardinale F, Castellarin SD, Schubert A. Characterization of a multifunctional caffeoyl-CoA O-methyltransferase activated in grape berries upon drought stress. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2016; 101:23-32. [PMID: 26851572 DOI: 10.1016/j.plaphy.2016.01.015] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 01/12/2016] [Accepted: 01/19/2016] [Indexed: 05/25/2023]
Abstract
Drought stress affects anthocyanin accumulation and modification in vegetative and reproductive plant tissues. Anthocyanins are the most abundant flavonoids in grape (Vitis vinifera L.) coloured berry genotypes and are essential markers of grape winemaking quality. They are mostly mono- and di-methylated, such modifications increase their stability and improve berry quality for winemaking. Anthocyanin methylation in grape berries is induced by drought stress. A few caffeoyl-CoA O-methyltransferases (CCoAOMTs) active on anthocyanins have been described in grape. However, no drought-activated O-methyltransferases have been described in grape berries yet. In this study, we characterized VvCCoAOMT, a grapevine gene known to induce methylation of CoA esters in cultured grape cells. Transcript accumulation of VvCCoAOMT was detected in berry skins, and increased during berry ripening on the plant, and in cultured berries treated with ABA, concomitantly with accumulation of methylated anthocyanins, suggesting that anthocyanins may be substrates of this enzyme. Contrary as previously observed in cell cultures, biotic stress (Botrytis cinerea inoculation) did not affect VvCCoAOMT gene expression in leaves or berries, while drought stress increased VvCCoAOMT transcript in berries. The recombinant VvCCoAOMT protein showed in vitro methylating activity on cyanidin 3-O-glucoside. We conclude that VvCCoAOMT is a multifunctional O-methyltransferase that may contribute to anthocyanin methylation activity in grape berries, in particular under drought stress conditions.
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Affiliation(s)
- Debora Giordano
- University of Turin, Dept. Agricultural, Forestry and Food Sciences, Largo Paolo Braccini 2, 10095 Grugliasco, TO, Italy
| | - Sofia Provenzano
- University of Turin, Dept. Agricultural, Forestry and Food Sciences, Largo Paolo Braccini 2, 10095 Grugliasco, TO, Italy
| | - Alessandra Ferrandino
- University of Turin, Dept. Agricultural, Forestry and Food Sciences, Largo Paolo Braccini 2, 10095 Grugliasco, TO, Italy
| | - Marco Vitali
- University of Turin, Dept. Agricultural, Forestry and Food Sciences, Largo Paolo Braccini 2, 10095 Grugliasco, TO, Italy
| | - Chiara Pagliarani
- University of Turin, Dept. Agricultural, Forestry and Food Sciences, Largo Paolo Braccini 2, 10095 Grugliasco, TO, Italy
| | - Federica Roman
- University of Turin, Dept. Agricultural, Forestry and Food Sciences, Largo Paolo Braccini 2, 10095 Grugliasco, TO, Italy
| | - Francesca Cardinale
- University of Turin, Dept. Agricultural, Forestry and Food Sciences, Largo Paolo Braccini 2, 10095 Grugliasco, TO, Italy
| | - Simone D Castellarin
- The University of British Columbia Wine Research Centre, 2205 East Mall, Vancouver, BC V6T 1Z4, Canada
| | - Andrea Schubert
- University of Turin, Dept. Agricultural, Forestry and Food Sciences, Largo Paolo Braccini 2, 10095 Grugliasco, TO, Italy.
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16
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Du H, Wu J, Ji KX, Zeng QY, Bhuiya MW, Su S, Shu QY, Ren HX, Liu ZA, Wang LS. Methylation mediated by an anthocyanin, O-methyltransferase, is involved in purple flower coloration in Paeonia. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:6563-77. [PMID: 26208646 PMCID: PMC4623676 DOI: 10.1093/jxb/erv365] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Anthocyanins are major pigments in plants. Methylation plays a role in the diversity and stability of anthocyanins. However, the contribution of anthocyanin methylation to flower coloration is still unclear. We identified two homologous anthocyanin O-methyltransferase (AOMT) genes from purple-flowered (PsAOMT) and red-flowered (PtAOMT) Paeonia plants, and we performed functional analyses of the two genes in vitro and in vivo. The critical amino acids for AOMT catalytic activity were studied by site-directed mutagenesis. We showed that the recombinant proteins, PsAOMT and PtAOMT, had identical substrate preferences towards anthocyanins. The methylation activity of PsAOMT was 60 times higher than that of PtAOMT in vitro. Interestingly, this vast difference in catalytic activity appeared to result from a single amino acid residue substitution at position 87 (arginine to leucine). There were significant differences between the 35S::PsAOMT transgenic tobacco and control flowers in relation to their chromatic parameters, which further confirmed the function of PsAOMT in vivo. The expression levels of the two homologous AOMT genes were consistent with anthocyanin accumulation in petals. We conclude that AOMTs are responsible for the methylation of cyanidin glycosides in Paeonia plants and play an important role in purple coloration in Paeonia spp.
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Affiliation(s)
- Hui Du
- Key Laboratory of Plant Resources/ Beijing Botanical Garden, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, PR China
| | - Jie Wu
- Key Laboratory of Plant Resources/ Beijing Botanical Garden, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, PR China University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Kui-Xian Ji
- Key Laboratory of Plant Resources/ Beijing Botanical Garden, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, PR China
| | - Qing-Yin Zeng
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, PR China
| | | | - Shang Su
- Key Laboratory of Plant Resources/ Beijing Botanical Garden, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, PR China University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Qing-Yan Shu
- Key Laboratory of Plant Resources/ Beijing Botanical Garden, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, PR China
| | - Hong-Xu Ren
- Key Laboratory of Plant Resources/ Beijing Botanical Garden, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, PR China
| | - Zheng-An Liu
- Key Laboratory of Plant Resources/ Beijing Botanical Garden, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, PR China
| | - Liang-Sheng Wang
- Key Laboratory of Plant Resources/ Beijing Botanical Garden, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, PR China
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17
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Xu RX, Zhao Y, Gao S, Zhang YY, Li DD, Lou HX, Cheng AX. Functional characterization of a plastidal cation-dependent O-methyltransferase from the liverwort Plagiochasma appendiculatum. PHYTOCHEMISTRY 2015; 118:33-41. [PMID: 26277769 DOI: 10.1016/j.phytochem.2015.08.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Revised: 06/26/2015] [Accepted: 08/04/2015] [Indexed: 06/04/2023]
Abstract
Caffeoyl CoA O-methyltransferases (CCoAOMTs), known to be involved in phenylpropanoid metabolism and lignin synthesis, have been characterized from several higher plant species, which also harbor CCoAOMT-like enzymes responsible for methylation of a variety of flavonoids, anthocyanins, coumarins and phenylpropanoids. Here, a gene encoding a CCoAOMT (PaOMT1) was isolated from a sequenced cDNA library of the liverwort species Plagiochasma appendiculatum, a species belonging to the Family Aytoniaceae. The full-length cDNA sequence of PaOMT1 contains 909 bp, and is predicted to encode a protein with 302 amino acids. The gene products were 40-50% identical to CCoAOMT sequences of other plants. Experiments based on recombinant PaOMT1 showed that the enzyme was able to methylate phenylpropanoids, flavonoids and coumarins, with a preference for the flavonoid quercetin (19). Although the substrate selectivity and biochemical feature of PaOMT1 is similar to CCoAOMT-like enzymes, the sequence alignment results indicated PaOMT1 is closer to true CCoAOMT enzymes. A phylogenetic analysis indicated that PaOMT1 is intermediate between true CCoAOMTs and CCoAOMT-like enzymes. The transient expression of a PaOMT1-GFP fusion in tobacco demonstrated that PaOMT1 is directed to the plastids. PaOMT1 may represent an ancestral form of higher plant true CCoAOMT and CCoAOMT-like enzymes. This is the first time an O-methyltransferase was characterized in liverworts.
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Affiliation(s)
- Rui-Xue Xu
- Key Laboratory of Chemical Biology of Natural Products, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, Jinan 250012, China
| | - Yu Zhao
- Key Laboratory of Chemical Biology of Natural Products, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, Jinan 250012, China
| | - Shuai Gao
- Key Laboratory of Chemical Biology of Natural Products, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, Jinan 250012, China
| | - Yu-Ying Zhang
- Key Laboratory of Chemical Biology of Natural Products, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, Jinan 250012, China
| | - Dan-Dan Li
- Key Laboratory of Chemical Biology of Natural Products, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, Jinan 250012, China
| | - Hong-Xiang Lou
- Key Laboratory of Chemical Biology of Natural Products, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, Jinan 250012, China
| | - Ai-Xia Cheng
- Key Laboratory of Chemical Biology of Natural Products, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, Jinan 250012, China.
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18
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Ma QH, Luo HR. Biochemical characterization of caffeoyl coenzyme A 3-O-methyltransferase from wheat. PLANTA 2015; 242:113-22. [PMID: 25854602 DOI: 10.1007/s00425-015-2295-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 03/30/2015] [Indexed: 05/09/2023]
Abstract
TaCCoAOMT1 is located in wheat chromosome 7A and highly expressed in stem and root. It is important for lignin biosynthesis, and associated with stem maturity but not lodging resistance. Caffeoyl coenzyme A 3-O-methyltransferases (CCoAOMTs) are one important class of enzymes to carry out the transfer of the methyl group from S-adenosylmethionine to the hydroxyl group, and play important roles in lignin and flavonoids biosynthesis. In the present study, sequences for CCoAOMT from the wheat genome were analyzed. One wheat CCoAOMT that belonged to bona fide subclade involved in lignin biosynthesis, namely TaCCoAOMT1, was obtained by the prokaryotic expression in E. coli. The three-dimensional structure prediction showed a highly similar structure of TaCCoAOMT1 with MsCCoAOMT. Recombinant TaCCoAOMT1 protein could only use caffeoyl CoA and 5-hydroxyferuloyl CoA as effective substrates and caffeoyl CoA as the best substrate. TaCCoAOMT1 had a narrow optimal pH and thermal stability. The TaCCoAOMT1 gene was highly expressed in wheat stem and root tissues, paralleled CCoAOMT enzyme activity. TaCCoAOMT1 mRNA abundance and enzyme activity increased linearly with stem maturity, but showed little difference between wheat lodging-resistant (H4546) and lodging-sensitive (C6001) cultivars in elongation, heading and milky stages. These data suggest that TaCCoAOMT1 is an important CCoAOMT for lignin biosynthesis that is critical for stem development, but not directly associated with lodging-resistant trait in wheat.
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Affiliation(s)
- Qing-Hu Ma
- Key Laboratory of Plant Resources and Beijing Botanical Garden, Institute of Botany, Chinese Academy of Sciences, 20 Nanxincun, Xiangshan, Beijing, 100093, China,
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Brandt W, Manke K, Vogt T. A catalytic triad--Lys-Asn-Asp--Is essential for the catalysis of the methyl transfer in plant cation-dependent O-methyltransferases. PHYTOCHEMISTRY 2015; 113:130-139. [PMID: 25596806 DOI: 10.1016/j.phytochem.2014.12.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Revised: 12/10/2014] [Accepted: 12/16/2014] [Indexed: 06/04/2023]
Abstract
Crystal structure data of cation-dependent catechol O-methyltransferases (COMTs) from mammals and related caffeoyl coenzyme A OMTs (CCoAOMTs) from plants have suggested operative molecular mechanisms. These include bivalent cations that facilitate deprotonation of vicinal aromatic dihydroxy systems and illustrate a conserved arrangement of hydroxyl and carboxyl ligands consistent with the requirements of a metal-activated catalytic mechanism. The general concept of metal-dependent deprotonation via a complexed aspartate is only one part of a more pronounced proton relay, as shown by semiempirical and DFT quantum mechanical calculations and experimental validations. A previously undetected catalytic triad, consisting of Lys157-Asn181-Asp228 residues is required for complete methyl transfer in case of a cation-dependent phenylpropanoid and flavonoid OMT, as described in this report. This triad appears essential for efficient methyl transfer to catechol-like hydroxyl group in phenolics. The observation is consistent with a catalytic lysine in the case of mammalian COMTs, but jettisons existing assumptions on the initial abstraction of the meta-hydroxyl proton to the metal stabilizing Asp154 (PFOMT) or comparable Asp-carboxyl groups in type of cation-dependent enzymes in plants. The triad is conserved among all characterized plant CCoAOMT-like enzymes, which are required not only for methylation of soluble phenylpropanoids like coumarins or monolignol monomers, but is also present in the similar microbial and mammalian cation-dependent enzymes which methylate a comparable set of substrates.
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Affiliation(s)
- Wolfgang Brandt
- Leibniz Institute of Plant Biochemistry, Dept. Bioorganic Chemistry, Weinberg 3, D-06120 Halle(Saale), Germany.
| | - Kerstin Manke
- Leibniz Institute of Plant Biochemistry, Dept. Cell and Metabolic Biology, Weinberg 3, D-06120 Halle(Saale), Germany
| | - Thomas Vogt
- Leibniz Institute of Plant Biochemistry, Dept. Cell and Metabolic Biology, Weinberg 3, D-06120 Halle(Saale), Germany
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20
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Byeon Y, Lee HY, Lee K, Back K. Caffeic acid O-methyltransferase is involved in the synthesis of melatonin by methylating N-acetylserotonin in Arabidopsis. J Pineal Res 2014; 57:219-27. [PMID: 25039887 DOI: 10.1111/jpi.12160] [Citation(s) in RCA: 109] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Accepted: 07/15/2014] [Indexed: 12/14/2022]
Abstract
Although a plant N-acetylserotonin methyltransferase (ASMT) was recently cloned from rice, homologous genes appear to be absent in dicotyledonous plants. To clone an ASMT de novo from a dicotyledonous plant, we expressed eight Arabidopsis thaliana O-methyltransferase (OMT) cDNAs in Escherichia coli and screened for ASMT activity by measuring melatonin production after the application of 1 mm N-acetylserotonin (NAS). Among the eight strains harboring the full-length cDNAs, the OMT3 strain produced high levels of melatonin, suggesting that OMT3 encodes an active ASMT. OMT3 is already known as caffeic acid OMT (COMT), suggesting multiple functions for this enzyme. The purified recombinant A. thaliana COMT (AtCOMT) showed high ASMT activity, catalyzing the conversion of NAS to melatonin. The Km and Vmax values for ASMT activity were 233 μm and 1800 pmol/min/mg protein, while the Km and Vmax values for COMT activity were 103 μm and 564,000 pmol/min/mg protein, respectively. The catalytic efficiency (Vmax /Km ) for ASMT activity was 709-fold lower than for COMT. In vitro, ASMT activity was dramatically decreased by the addition of caffeic acid in a dose-dependent manner, but the activity of COMT was not altered by NAS. Lastly, the Arabidopsis comt knockout mutant exhibited less production of melatonin than the wild type when Arabidopsis leaves were infiltrated with 1 mm NAS, suggestive of in vivo role of COMT in melatonin biosynthesis in plants.
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Affiliation(s)
- Yeong Byeon
- Department of Biotechnology, Bioenergy Research Center, Chonnam National University, Gwangju, Korea
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21
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Galland M, Boutet-Mercey S, Lounifi I, Godin B, Balzergue S, Grandjean O, Morin H, Perreau F, Debeaujon I, Rajjou L. Compartmentation and Dynamics of Flavone Metabolism in Dry and Germinated Rice Seeds. ACTA ACUST UNITED AC 2014; 55:1646-59. [DOI: 10.1093/pcp/pcu095] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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22
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Lam PY, Zhu FY, Chan WL, Liu H, Lo C. Cytochrome P450 93G1 Is a Flavone Synthase II That Channels Flavanones to the Biosynthesis of Tricin O-Linked Conjugates in Rice. PLANT PHYSIOLOGY 2014; 165:1315-1327. [PMID: 24843076 PMCID: PMC4081339 DOI: 10.1104/pp.114.239723] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Abstract
Flavones are a major class of flavonoids with a wide range of physiological functions in plants. They are constitutively accumulated as C-glycosides and O-linked conjugates in vegetative tissues of grasses. It has long been presumed that the two structural modifications of flavones occur through independent metabolic routes. Previously, we reported that cytochrome P450 93G2 (CYP93G2) functions as a flavanone 2-hydroxylase (F2H) that provides 2-hydroxyflavanones for C-glycosylation in rice (Oryza sativa). Flavone C-glycosides are subsequently formed by dehydratase activity on 2-hydroxyflavanone C-glycosides. On the other hand, O-linked modifications were proposed to proceed after the flavone nucleus is generated. In this study, we demonstrate that CYP93G1, the closest homolog of CYP93G2 in rice, is a bona fide flavone synthase II (FNSII) that catalyzes the direct conversion of flavanones to flavones. In recombinant enzyme assays, CYP93G1 desaturated naringenin and eriodictyol to apigenin and luteolin, respectively. Consistently, transgenic expression of CYP93G1 in Arabidopsis (Arabidopsis thaliana) resulted in the accumulation of different flavone O-glycosides, which are not naturally present in cruciferous plants. Metabolite analysis of a rice CYP93G1 insertion mutant further demonstrated the preferential depletion of tricin O-linked flavanolignans and glycosides. By contrast, redirection of metabolic flow to the biosynthesis of flavone C-glycosides was observed. Our findings established that CYP93G1 is a key branch point enzyme channeling flavanones to the biosynthesis of tricin O-linked conjugates in rice. Functional diversification of F2H and FNSII in the cytochrome P450 CYP93G subfamily may represent a lineage-specific event leading to the prevalent cooccurrence of flavone C- and O-linked derivatives in grasses today.
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Affiliation(s)
- Pui Ying Lam
- School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China (P.Y.L., F.-Y.Z., W.L.C., C.L.); and
| | - Fu-Yuan Zhu
- School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China (P.Y.L., F.-Y.Z., W.L.C., C.L.); and
| | - Wai Lung Chan
- School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China (P.Y.L., F.-Y.Z., W.L.C., C.L.); and
| | - Hongjia Liu
- State Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Institute of Crops and Nuclear Technology Utilization, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China (H.L.)
| | - Clive Lo
- School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China (P.Y.L., F.-Y.Z., W.L.C., C.L.); and
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Berim A, Gang DR. Characterization of two candidate flavone 8-O-methyltransferases suggests the existence of two potential routes to nevadensin in sweet basil. PHYTOCHEMISTRY 2013; 92:33-41. [PMID: 23747095 DOI: 10.1016/j.phytochem.2013.05.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2012] [Revised: 03/07/2013] [Accepted: 05/08/2013] [Indexed: 06/02/2023]
Abstract
Regioselective 6-,7-,8-,3'-, and 4'-O-methylations underlie the structural diversity of lipophilic flavones produced in the trichomes of sweet basil (Ocimum basilicum L.). The positions 6, 7, and 4' are methylated by a recently described set of cation-independent enzymes. The roles of cation-dependent O-methyltransferases still require elucidation. Here, the basil trichome EST database was used to identify a Mg(2+)-dependent O-methyltransferase that was likely to accept flavonoids as substrates. The recombinant protein was found to be active with a wide range of o-diphenols, and methylated the 8-OH moiety of the flavone backbone with higher catalytic efficiency than the 3'-OH group of candidate substrates. To further investigate flavone 8-O-methylation, the activity of a putative cation-independent flavonoid 8-O-methyltransferase from the same EST collection was assessed with available substrate analogs. Notably, it was strongly inhibited by gardenin B, one of its expected products. The catalytic capacities of the two studied proteins suggest that two alternative routes to nevadensin, a major flavone in some basil cultivars, might exist. Correlating the expression of the underlying genes with the accumulation of 8-substituted flavones in four basil lines did not clarify which is the major operating pathway in vivo, yet the combined data suggested that the biochemical properties of flavone 7-O-demethylase could play a key role in determining the reaction order.
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Affiliation(s)
- Anna Berim
- Institute of Biological Chemistry, Washington State University, Pullman, WA 99164, USA
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24
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Characterization of regiospecific flavonoid 3′/5′-O-methyltransferase from tomato and its application in flavonoid biotransformation. ACTA ACUST UNITED AC 2012. [DOI: 10.1007/s13765-012-2193-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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25
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Akita Y, Kitamura S, Hase Y, Narumi I, Ishizaka H, Kondo E, Kameari N, Nakayama M, Tanikawa N, Morita Y, Tanaka A. Isolation and characterization of the fragrant cyclamen O-methyltransferase involved in flower coloration. PLANTA 2011; 234:1127-36. [PMID: 21735197 DOI: 10.1007/s00425-011-1466-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Accepted: 06/17/2011] [Indexed: 05/26/2023]
Abstract
Anthocyanin O-methyltransferase (OMT) is one of the key enzymes for anthocyanin modification and flower pigmentation. We previously bred a novel red-purple-flowered fragrant cyclamen (KMrp) from the purple-flowered fragrant cyclamen 'Kaori-no-mai' (KM) by ion-beam irradiation. Since the major anthocyanins in KMrp and KM petals were delphinidin 3,5-diglucoside and malvidin 3,5-diglucoside, respectively, inactivation of a methylation step in the anthocyanin biosynthetic pathway was indicated in KMrp. We isolated and compared OMT genes expressed in KM and KMrp petals. RT-PCR analysis revealed that CkmOMT2 was expressed in the petals of KM but not in KMrp. Three additional CkmOMTs with identical sequences were expressed in petals of both KM and KMrp. Genomic PCR analysis revealed that CkmOMT2 was not amplified from the KMrp genome, indicating that ion-beam irradiation caused a loss of the entire CkmOMT2 region in KMrp. In vitro enzyme assay demonstrated that CkmOMT2 catalyzes the 3' or 3',5' O-methylation of the B-ring of anthocyanin substrates. These results suggest that CkmOMT2 is functional for anthocyanin methylation, and defective expression of CkmOMT2 is responsible for changes in anthocyanin composition and flower coloration in KMrp.
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Affiliation(s)
- Yusuke Akita
- Quantum Beam Science Directorate, Japan Atomic Energy Agency, 1233 Watanuki, Takasaki, Gunma, 370-1292, Japan.
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26
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Widiez T, Hartman TG, Dudai N, Yan Q, Lawton M, Havkin-Frenkel D, Belanger FC. Functional characterization of two new members of the caffeoyl CoA O-methyltransferase-like gene family from Vanilla planifolia reveals a new class of plastid-localized O-methyltransferases. PLANT MOLECULAR BIOLOGY 2011; 76:475-88. [PMID: 21629984 DOI: 10.1007/s11103-011-9772-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Accepted: 03/22/2011] [Indexed: 05/19/2023]
Abstract
Caffeoyl CoA O-methyltransferases (OMTs) have been characterized from numerous plant species and have been demonstrated to be involved in lignin biosynthesis. Higher plant species are known to have additional caffeoyl CoA OMT-like genes, which have not been well characterized. Here, we identified two new caffeoyl CoA OMT-like genes by screening a cDNA library from specialized hair cells of pods of the orchid Vanilla planifolia. Characterization of the corresponding two enzymes, designated Vp-OMT4 and Vp-OMT5, revealed that in vitro both enzymes preferred as a substrate the flavone tricetin, yet their sequences and phylogenetic relationships to other enzymes are distinct from each other. Quantitative analysis of gene expression indicated a dramatic tissue-specific expression pattern for Vp-OMT4, which was highly expressed in the hair cells of the developing pod, the likely location of vanillin biosynthesis. Although Vp-OMT4 had a lower activity with the proposed vanillin precursor, 3,4-dihydroxybenzaldehyde, than with tricetin, the tissue specificity of expression suggests it may be a candidate for an enzyme involved in vanillin biosynthesis. In contrast, the Vp-OMT5 gene was mainly expressed in leaf tissue and only marginally expressed in pod hair cells. Phylogenetic analysis suggests Vp-OMT5 evolved from a cyanobacterial enzyme and it clustered within a clade in which the sequences from eukaryotic species had predicted chloroplast transit peptides. Transient expression of a GFP-fusion in tobacco demonstrated that Vp-OMT5 was localized in the plastids. This is the first flavonoid OMT demonstrated to be targeted to the plastids.
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Affiliation(s)
- Thomas Widiez
- Department of Plant Biology and Pathology, School of Environmental and Biological Sciences, Rutgers University, 59 Dudley Road, New Brunswick, NJ 08901, USA
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27
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Schmidt A, Li C, Shi F, Jones AD, Pichersky E. Polymethylated myricetin in trichomes of the wild tomato species Solanum habrochaites and characterization of trichome-specific 3'/5'- and 7/4'-myricetin O-methyltransferases. PLANT PHYSIOLOGY 2011; 155:1999-2009. [PMID: 21343428 PMCID: PMC3091102 DOI: 10.1104/pp.110.169961] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2010] [Accepted: 02/20/2011] [Indexed: 05/18/2023]
Abstract
Flavonoids are a class of metabolites found in many plant species. They have been reported to serve several physiological roles, such as in defense against herbivores and pathogens and in protection against harmful ultraviolet radiation. They also serve as precursors of pigment compounds found in flowers, leaves, and seeds. Highly methylated, nonglycosylated derivatives of the flavonoid myricetin flavonoid, have been previously reported from a variety of plants, but O-methyltransferases responsible for their synthesis have not yet been identified. Here, we show that secreting glandular trichomes (designated types 1 and 4) and storage glandular trichomes (type 6) on the leaf surface of wild tomato (Solanum habrochaites accession LA1777) plants contain 3,7,3'-trimethyl myricetin, 3,7,3',5'-tetramethyl myricetin, and 3,7,3',4',5'-pentamethyl myricetin, with gland types 1 and 4 containing severalfold more of these compounds than type 6 glands and with the tetramethylated compound predominating in all three gland types. We have also identified transcripts of two genes expressed in the glandular trichomes and showed that they encode enzymes capable of methylating myricetin at the 3' and 5' and the 7 and 4' positions, respectively. Both genes are preferentially expressed in secreting glandular trichome types 1 and 4 and to a lesser degree in storage trichome type 6, and the levels of the proteins they encode are correspondingly higher in types 1 and 4 glands compared with type 6 glands.
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Affiliation(s)
| | | | | | | | - Eran Pichersky
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan 48109–1048 (A.S., E.P.); Department of Chemistry (C.L., F.S., A.D.J.) and Department of Biochemistry and Molecular Biology (A.D.J.), Michigan State University, East Lansing, Michigan 48824
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28
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Kim BG, Kim DH, Sung SH, Kim DE, Chong Y, Ahn JH. Two O-methyltransferases from Picea abies: characterization and molecular basis of different reactivity. PLANTA 2010; 232:837-844. [PMID: 20628758 DOI: 10.1007/s00425-010-1223-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2010] [Accepted: 06/29/2010] [Indexed: 05/29/2023]
Abstract
O-Methyltransferase (OMT) catalyzes the transfer of a methyl group from S-adenosyl methionine (SAM) to hydroxyl groups of methyl acceptors. Two OMTs, PaOMT2 and PaOMT3, from Picea abies showed 93.5% identity at the amino acid level. However, PaOMT3 catalyzed the reaction more efficiently than PaOMT2 with several phenolic compounds, including quercetin and caffeoyl-CoA. To determine the critical amino acids for the different reactivity of the two OMTs, site-directed mutagenesis was carried out. The amino acid proline at position 35 in PaOMT2 and leucine in PaOMT3 is a critical amino acid for their reactivity. Molecular modeling showed that the sequential change triggered by Leu35 resulted in a change in the size of the substrate binding pocket, which could account for the different catalytic reactivity of two OMTs.
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Affiliation(s)
- Bong-Gyu Kim
- Department of Bioscience and Biotechnology, Bio/Molecular Informatics Center, Konkuk University, Seoul, Korea
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29
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Joe EJ, Kim BG, An BC, Chong Y, Ahn JH. Engineering of flavonoid O-methyltransferase for a novel regioselectivity. Mol Cells 2010; 30:137-41. [PMID: 20680484 DOI: 10.1007/s10059-010-0098-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2010] [Revised: 04/27/2010] [Accepted: 04/27/2010] [Indexed: 10/19/2022] Open
Abstract
An O-methyltransferase isolated from poplar, POMT7, was identified as a flavone 7-O-methyltransferase. In order to generate a mutant of POMT-7 having a novel regioselectivity, we conducted an error-prone polymerase chain reaction. More than 100 mutants were screened and one of the mutants (POMT-M1) Asp257Gly, methylated the 3-hydroxyl group of flavonols in addition to 7-hydrdoxyl group. The mutation changed asparagine residue at the position of 257 into glycine. The kinetic parameters showed that the wild type POMT7 was better activity toward kaempferol and quercetin than the POMT7-M1. Using E. coli transformant expressing POMT7-M1, 58 microM of 3, 7-O-dimethylquercetin and 70 microM of 3, 7-O-dimethylkaempferol from 100 microM of corresponding substrate were synthesized successfully.
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Affiliation(s)
- Eun Ji Joe
- Department of Bioscience and Biotechnology, Bio/Molecular Informatics Center, Konkuk University, Seoul 143-701, Korea
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30
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Kim BG, Sung SH, Jung NR, Chong Y, Ahn JH. Biological synthesis of isorhamnetin 3-O-glucoside using engineered glucosyltransferase. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/j.molcatb.2010.01.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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31
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Sequence analysis, in silico modeling and docking studies of Caffeoyl CoA-O-methyltransferase of Populus trichopora. J Mol Model 2010; 16:1461-71. [DOI: 10.1007/s00894-010-0656-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2009] [Accepted: 01/05/2010] [Indexed: 10/19/2022]
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32
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Structural Modeling and Biochemical Characterization of Flavonoid O-Methyltransferase from Rice. B KOREAN CHEM SOC 2009. [DOI: 10.5012/bkcs.2009.30.11.2803] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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33
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Kim DH, Kim SK, Kim JH, Kim BG, Ahn JH. Molecular characterization of flavonoid malonyltransferase from Oryza sativa. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2009; 47:991-997. [PMID: 19733090 DOI: 10.1016/j.plaphy.2009.08.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2009] [Revised: 05/29/2009] [Accepted: 08/14/2009] [Indexed: 05/28/2023]
Abstract
In this study, a flavonoid malonyltransferase (OsMaT-2) was cloned from Oryza sativa, and the recombinant protein OsMaT-2 was purified via affinity chromatography. OsMaT-2 utilized a variety of flavonoid glucosides, including flavanone glucosides, flavone glucosides, flavonol glucosides, and isoflavone glucosides as substrates, but did not utilize anthocyanin. As an acyl donor, OsMaT-2 utilized only malonyl-CoA. Based on reactions with various quercetin 3-O-sugars, we identified the probable position of malonylation as the 6''-hydroxyl group of the sugar. This is the first report, to the best of our knowledge, of the cloning of a flavonoid malonyltransferase from O. sativa.
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Affiliation(s)
- Dea Hwan Kim
- Department of Bioscience and Biotechnology, Bio/Molecular Informatics Center, Konkuk University, Seoul 143-701, Republic of Korea
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34
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Hugueney P, Provenzano S, Verriès C, Ferrandino A, Meudec E, Batelli G, Merdinoglu D, Cheynier V, Schubert A, Ageorges A. A novel cation-dependent O-methyltransferase involved in anthocyanin methylation in grapevine. PLANT PHYSIOLOGY 2009; 150:2057-70. [PMID: 19525322 PMCID: PMC2719152 DOI: 10.1104/pp.109.140376] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2009] [Accepted: 06/10/2009] [Indexed: 05/18/2023]
Abstract
Anthocyanins are major pigments in colored grape (Vitis vinifera) berries, and most of them are monomethoxylated or dimethoxylated. We report here the functional characterization of an anthocyanin O-methyltransferase (AOMT) from grapevine. The expression pattern in two cultivars with different anthocyanin methylation profiles (Syrah and Nebbiolo) showed a peak at start ripening (véraison), when the concentrations of all methylated anthocyanins begin to increase. The purified recombinant AOMT protein was active on both anthocyanins and flavonols in vitro, with K(m) in the micromolar range, and was dependent on divalent cations for activity. AOMT showed a preference for 3',5' methylation when a 3',4',5' hydroxylated anthocyanin substrate was tested. In order to assess its in planta activity, we performed transient expression of AOMT in tobacco (Nicotiana benthamiana) leaves expressing the Production of Anthocyanin Pigment1 (PAP1) transcription factor from Arabidopsis (Arabidopsis thaliana). PAP1 expression in leaves induced the accumulation of the nonmethylated anthocyanin delphinidin 3-rutinoside. The coexpression of PAP1 and AOMT resulted in an accumulation of malvidin 3-rutinoside. We also showed that AOMT localized exclusively in the cytoplasm of tobacco leaf cells. These results demonstrate the ability of this enzyme to methylate anthocyanins both in vitro and in vivo, indicating that AOMT plays a major role in anthocyanin biosynthesis in grape berries.
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35
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Kim BG, Lee YJ, Lee S, Lim Y, Cheong Y, Ahn JH. Altered regioselectivity of a poplar O-methyltransferase, POMT-7. J Biotechnol 2008; 138:107-11. [DOI: 10.1016/j.jbiotec.2008.08.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2008] [Revised: 08/13/2008] [Accepted: 08/20/2008] [Indexed: 10/21/2022]
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36
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Structural and Functional Insights into O-Methyltransferase from Bacillus cereus. J Mol Biol 2008; 382:987-97. [DOI: 10.1016/j.jmb.2008.07.080] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2008] [Revised: 07/16/2008] [Accepted: 07/23/2008] [Indexed: 11/18/2022]
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