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Lacchini E, Erffelinck ML, Mertens J, Marcou S, Molina-Hidalgo FJ, Tzfadia O, Venegas-Molina J, Cárdenas PD, Pollier J, Tava A, Bak S, Höfte M, Goossens A. The saponin bomb: a nucleolar-localized β-glucosidase hydrolyzes triterpene saponins in Medicago truncatula. THE NEW PHYTOLOGIST 2023; 239:705-719. [PMID: 36683446 DOI: 10.1111/nph.18763] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 01/09/2023] [Indexed: 06/15/2023]
Abstract
Plants often protect themselves from their own bioactive defense metabolites by storing them in less active forms. Consequently, plants also need systems allowing correct spatiotemporal reactivation of such metabolites, for instance under pathogen or herbivore attack. Via co-expression analysis with public transcriptomes, we determined that the model legume Medicago truncatula has evolved a two-component system composed of a β-glucosidase, denominated G1, and triterpene saponins, which are physically separated from each other in intact cells. G1 expression is root-specific, stress-inducible, and coregulated with that of the genes encoding the triterpene saponin biosynthetic enzymes. However, the G1 protein is stored in the nucleolus and is released and united with its typically vacuolar-stored substrates only upon tissue damage, partly mediated by the surfactant action of the saponins themselves. Subsequently, enzymatic removal of carbohydrate groups from the saponins creates a pool of metabolites with an increased broad-spectrum antimicrobial activity. The evolution of this defense system benefited from both the intrinsic condensation abilities of the enzyme and the bioactivity properties of its substrates. We dub this two-component system the saponin bomb, in analogy with the mustard oil and cyanide bombs, commonly used to describe the renowned β-glucosidase-dependent defense systems for glucosinolates and cyanogenic glucosides.
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Affiliation(s)
- Elia Lacchini
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, B-9052, Belgium
- VIB Center for Plant Systems Biology, Ghent, B-9052, Belgium
| | - Marie-Laure Erffelinck
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, B-9052, Belgium
- VIB Center for Plant Systems Biology, Ghent, B-9052, Belgium
| | - Jan Mertens
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, B-9052, Belgium
- VIB Center for Plant Systems Biology, Ghent, B-9052, Belgium
| | - Shirley Marcou
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Ghent, B-9000, Belgium
| | - Francisco Javier Molina-Hidalgo
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, B-9052, Belgium
- VIB Center for Plant Systems Biology, Ghent, B-9052, Belgium
| | - Oren Tzfadia
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, B-9052, Belgium
- VIB Center for Plant Systems Biology, Ghent, B-9052, Belgium
| | - Jhon Venegas-Molina
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, B-9052, Belgium
- VIB Center for Plant Systems Biology, Ghent, B-9052, Belgium
| | - Pablo D Cárdenas
- Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg C, DK-1871, Denmark
| | - Jacob Pollier
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, B-9052, Belgium
- VIB Center for Plant Systems Biology, Ghent, B-9052, Belgium
| | - Aldo Tava
- CREA Research Centre for Animal Production and Aquaculture, Lodi, 26900, Italy
| | - Søren Bak
- Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg C, DK-1871, Denmark
| | - Monica Höfte
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Ghent, B-9000, Belgium
| | - Alain Goossens
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, B-9052, Belgium
- VIB Center for Plant Systems Biology, Ghent, B-9052, Belgium
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2
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Carqueijeiro I, Koudounas K, Dugé de Bernonville T, Sepúlveda LJ, Mosquera A, Bomzan DP, Oudin A, Lanoue A, Besseau S, Lemos Cruz P, Kulagina N, Stander EA, Eymieux S, Burlaud-Gaillard J, Blanchard E, Clastre M, Atehortùa L, St-Pierre B, Giglioli-Guivarc’h N, Papon N, Nagegowda DA, O’Connor SE, Courdavault V. Alternative splicing creates a pseudo-strictosidine β-d-glucosidase modulating alkaloid synthesis in Catharanthus roseus. PLANT PHYSIOLOGY 2021; 185:836-856. [PMID: 33793899 PMCID: PMC8133614 DOI: 10.1093/plphys/kiaa075] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 11/24/2020] [Indexed: 05/08/2023]
Abstract
Deglycosylation is a key step in the activation of specialized metabolites involved in plant defense mechanisms. This reaction is notably catalyzed by β-glucosidases of the glycosyl hydrolase 1 (GH1) family such as strictosidine β-d-glucosidase (SGD) from Catharanthus roseus. SGD catalyzes the deglycosylation of strictosidine, forming a highly reactive aglycone involved in the synthesis of cytotoxic monoterpene indole alkaloids (MIAs) and in the crosslinking of aggressor proteins. By exploring C. roseus transcriptomic resources, we identified an alternative splicing event of the SGD gene leading to the formation of a shorter isoform of this enzyme (shSGD) that lacks the last 71-residues and whose transcript ratio with SGD ranges from 1.7% up to 42.8%, depending on organs and conditions. Whereas it completely lacks β-glucosidase activity, shSGD interacts with SGD and causes the disruption of SGD multimers. Such disorganization drastically inhibits SGD activity and impacts downstream MIA synthesis. In addition, shSGD disrupts the metabolic channeling of downstream biosynthetic steps by hampering the recruitment of tetrahydroalstonine synthase in cell nuclei. shSGD thus corresponds to a pseudo-enzyme acting as a regulator of MIA biosynthesis. These data shed light on a peculiar control mechanism of β-glucosidase multimerization, an organization common to many defensive GH1 members.
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Affiliation(s)
- Inês Carqueijeiro
- EA2106 “Biomolécules et Biotechnologies Végétales,” Université de Tours, 37200 Tours, France
| | - Konstantinos Koudounas
- EA2106 “Biomolécules et Biotechnologies Végétales,” Université de Tours, 37200 Tours, France
| | | | - Liuda Johana Sepúlveda
- EA2106 “Biomolécules et Biotechnologies Végétales,” Université de Tours, 37200 Tours, France
- Laboratorio de Biotecnología, Universidad de Antioquia, Sede de Investigación Universitaria, 50010 Medellin, Colombia
| | - Angela Mosquera
- EA2106 “Biomolécules et Biotechnologies Végétales,” Université de Tours, 37200 Tours, France
- Laboratorio de Biotecnología, Universidad de Antioquia, Sede de Investigación Universitaria, 50010 Medellin, Colombia
| | - Dikki Pedenla Bomzan
- Molecular Plant Biology and Biotechnology Lab, CSIR-Central Institute of Medicinal and Aromatic Plants, Research Centre, Bengaluru 560065, India
| | - Audrey Oudin
- EA2106 “Biomolécules et Biotechnologies Végétales,” Université de Tours, 37200 Tours, France
| | - Arnaud Lanoue
- EA2106 “Biomolécules et Biotechnologies Végétales,” Université de Tours, 37200 Tours, France
| | - Sébastien Besseau
- EA2106 “Biomolécules et Biotechnologies Végétales,” Université de Tours, 37200 Tours, France
| | - Pamela Lemos Cruz
- EA2106 “Biomolécules et Biotechnologies Végétales,” Université de Tours, 37200 Tours, France
| | - Natalja Kulagina
- EA2106 “Biomolécules et Biotechnologies Végétales,” Université de Tours, 37200 Tours, France
| | - Emily A Stander
- EA2106 “Biomolécules et Biotechnologies Végétales,” Université de Tours, 37200 Tours, France
| | - Sébastien Eymieux
- INSERM U1259, Plateforme IBiSA de Microscopie Electronique, Université de Tours, 37200 Tours, France
| | - Julien Burlaud-Gaillard
- INSERM U1259, Plateforme IBiSA de Microscopie Electronique, Université de Tours, 37200 Tours, France
| | - Emmanuelle Blanchard
- INSERM U1259, Plateforme IBiSA de Microscopie Electronique, Université de Tours, 37200 Tours, France
- Centre Hospitalier Régional de Tours, 37170 Tours, France
| | - Marc Clastre
- EA2106 “Biomolécules et Biotechnologies Végétales,” Université de Tours, 37200 Tours, France
| | - Lucia Atehortùa
- Laboratorio de Biotecnología, Universidad de Antioquia, Sede de Investigación Universitaria, 50010 Medellin, Colombia
| | - Benoit St-Pierre
- EA2106 “Biomolécules et Biotechnologies Végétales,” Université de Tours, 37200 Tours, France
| | | | - Nicolas Papon
- EA3142 “Groupe d'Etude des Interactions Hôte-Pathogène,” Université d’Angers, 49035 Angers, France
| | - Dinesh A Nagegowda
- Molecular Plant Biology and Biotechnology Lab, CSIR-Central Institute of Medicinal and Aromatic Plants, Research Centre, Bengaluru 560065, India
| | - Sarah E O’Connor
- Department of Natural Product Biosynthesis, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany
| | - Vincent Courdavault
- EA2106 “Biomolécules et Biotechnologies Végétales,” Université de Tours, 37200 Tours, France
- Author for communication:
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Park CK, Horton NC. Structures, functions, and mechanisms of filament forming enzymes: a renaissance of enzyme filamentation. Biophys Rev 2019; 11:927-994. [PMID: 31734826 PMCID: PMC6874960 DOI: 10.1007/s12551-019-00602-6] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 10/24/2019] [Indexed: 12/19/2022] Open
Abstract
Filament formation by non-cytoskeletal enzymes has been known for decades, yet only relatively recently has its wide-spread role in enzyme regulation and biology come to be appreciated. This comprehensive review summarizes what is known for each enzyme confirmed to form filamentous structures in vitro, and for the many that are known only to form large self-assemblies within cells. For some enzymes, studies describing both the in vitro filamentous structures and cellular self-assembly formation are also known and described. Special attention is paid to the detailed structures of each type of enzyme filament, as well as the roles the structures play in enzyme regulation and in biology. Where it is known or hypothesized, the advantages conferred by enzyme filamentation are reviewed. Finally, the similarities, differences, and comparison to the SgrAI endonuclease system are also highlighted.
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Affiliation(s)
- Chad K. Park
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ 85721 USA
| | - Nancy C. Horton
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ 85721 USA
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RAWAT RENU, GULATI ASHU, JOSHI ROBIN. PARTIAL PURIFICATION AND CHARACTERIZATION OF β-GLUCOSIDASE FROM TEA SHOOT. J Food Biochem 2011. [DOI: 10.1111/j.1745-4514.2010.00422.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Kwak SN, Kim SY, Choi SR, Kim IS. Assembly and function of AsGlu2 fibrillar multimer of oat beta-glucosidase. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2008; 1794:526-31. [PMID: 19100871 DOI: 10.1016/j.bbapap.2008.11.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2008] [Revised: 10/12/2008] [Accepted: 11/19/2008] [Indexed: 11/17/2022]
Abstract
Oat beta-glucosidase in plastid exists as a long fibrillar structure of AsGlu1 homomultimer (type I) and heteromultimer of AsGlu1 and AsGlu2 (type II). In spite of the high amino acid sequence homology of AsGlu1 and AsGlu2, AsGlu1 assembles into the fibrillar multimers but AsGlu2 forms a dimer when expressed in E. coli. A swapping analysis of AsGlu2 cDNA with AsGlu1 cDNA indicated that the C-terminal segment of AsGlu1 was critical for the fibrillar multimerization. A single substitution of glutamic acid-495 of AsGlu2 in the C-terminal region with lysine, an AsGlu1 counterpart amino acid for the glutamic acid-495, assembled the AsGlu2 into fibrillar homomultimers. The mutant AsGlu2 homomultimer was highly stable and had relatively faster electric mobility in native gel than the AsGlu1 homomultimer. Multimerization increased enzyme affinity to substrates.
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Affiliation(s)
- Su-Nam Kwak
- Department of Life Science and Biotechnology, College of Natural Science, Kyungpook National University, Daegu 702-701, South Korea
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6
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Morant AV, Bjarnholt N, Kragh ME, Kjaergaard CH, Jørgensen K, Paquette SM, Piotrowski M, Imberty A, Olsen CE, Møller BL, Bak S. The beta-glucosidases responsible for bioactivation of hydroxynitrile glucosides in Lotus japonicus. PLANT PHYSIOLOGY 2008; 147:1072-91. [PMID: 18467457 PMCID: PMC2442532 DOI: 10.1104/pp.107.109512] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2007] [Accepted: 05/06/2008] [Indexed: 05/18/2023]
Abstract
Lotus japonicus accumulates the hydroxynitrile glucosides lotaustralin, linamarin, and rhodiocyanosides A and D. Upon tissue disruption, the hydroxynitrile glucosides are bioactivated by hydrolysis by specific beta-glucosidases. A mixture of two hydroxynitrile glucoside-cleaving beta-glucosidases was isolated from L. japonicus leaves and identified by protein sequencing as LjBGD2 and LjBGD4. The isolated hydroxynitrile glucoside-cleaving beta-glucosidases preferentially hydrolyzed rhodiocyanoside A and lotaustralin, whereas linamarin was only slowly hydrolyzed, in agreement with measurements of their rate of degradation upon tissue disruption in L. japonicus leaves. Comparative homology modeling predicted that LjBGD2 and LjBGD4 had nearly identical overall topologies and substrate-binding pockets. Heterologous expression of LjBGD2 and LjBGD4 in Arabidopsis (Arabidopsis thaliana) enabled analysis of their individual substrate specificity profiles and confirmed that both LjBGD2 and LjBGD4 preferentially hydrolyze the hydroxynitrile glucosides present in L. japonicus. Phylogenetic analyses revealed a third L. japonicus putative hydroxynitrile glucoside-cleaving beta-glucosidase, LjBGD7. Reverse transcription-polymerase chain reaction analysis showed that LjBGD2 and LjBGD4 are expressed in aerial parts of young L. japonicus plants, while LjBGD7 is expressed exclusively in roots. The differential expression pattern of LjBGD2, LjBGD4, and LjBGD7 corresponds to the previously observed expression profile for CYP79D3 and CYP79D4, encoding the two cytochromes P450 that catalyze the first committed step in the biosyntheis of hydroxynitrile glucosides in L. japonicus, with CYP79D3 expression in aerial tissues and CYP79D4 expression in roots.
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Affiliation(s)
- Anne Vinther Morant
- Plant Biochemistry Laboratory, Department of Plant Biology, Center for Molecular Plant Physiology and VKR Research Centre "Pro-Active Plants" , University of Copenhagen, DK-1871 Frederiksberg C, Copenhagen, Denmark
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7
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Morant AV, Jørgensen K, Jørgensen C, Paquette SM, Sánchez-Pérez R, Møller BL, Bak S. beta-Glucosidases as detonators of plant chemical defense. PHYTOCHEMISTRY 2008; 69:1795-813. [PMID: 18472115 DOI: 10.1016/j.phytochem.2008.03.006] [Citation(s) in RCA: 300] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2008] [Accepted: 03/06/2008] [Indexed: 05/03/2023]
Abstract
Some plant secondary metabolites are classified as phytoanticipins. When plant tissue in which they are present is disrupted, the phytoanticipins are bio-activated by the action of beta-glucosidases. These binary systems--two sets of components that when separated are relatively inert--provide plants with an immediate chemical defense against protruding herbivores and pathogens. This review provides an update on our knowledge of the beta-glucosidases involved in activation of the four major classes of phytoanticipins: cyanogenic glucosides, benzoxazinoid glucosides, avenacosides and glucosinolates. New aspects of the role of specific proteins that either control oligomerization of the beta-glucosidases or modulate their product specificity are discussed in an evolutionary perspective.
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Affiliation(s)
- Anne Vinther Morant
- Plant Biochemistry Laboratory, Department of Plant Biology and The VKR Research Centre Proactive Plants, University of Copenhagen, 40 Thorvaldsensvej, DK-1871 Frederiksberg C, Copenhagen, Denmark
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8
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Sherameti I, Venus Y, Drzewiecki C, Tripathi S, Dan VM, Nitz I, Varma A, Grundler FM, Oelmüller R. PYK10, a beta-glucosidase located in the endoplasmatic reticulum, is crucial for the beneficial interaction between Arabidopsis thaliana and the endophytic fungus Piriformospora indica. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2008; 54:428-39. [PMID: 18248598 DOI: 10.1111/j.1365-313x.2008.03424.x] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Piriformospora indica, an endophyte of the Sebacinaceae family, promotes growth and seed production of many plant species, including Arabidopsis. Growth of a T-DNA insertion line in PYK10 is not promoted and the plants do not produce more seeds in the presence of P. indica, although their roots are more colonized by the fungus than wild-type roots. Overexpression of PYK10 mRNA did not affect root colonization and the response to the fungus. PYK10 codes for a root- and hypocotyl-specific beta-glucosidase/myrosinase, which is implicated to be involved in plant defences against herbivores and pathogens. Expression of PYK10 is activated by the basic helix-loop-helix domain containing transcription factor NAI1, and two Arabidopsis lines with mutations in the NAI1 gene show the same response to P. indica as the PYK10 insertion line. PYK10 transcript and PYK10 protein levels are severely reduced in a NAI1 mutant, indicating that PYK10 and not the transcription factor NAI1 is responsible for the response to the fungus. In wild-type roots, the message level for a leucine-rich repeat protein LRR1, but not for plant defensin 1.2 (PDF1.2), is upregulated in the presence of P. indica. In contrast, in lines with reduced PYK10 levels the PDF1.2, but not LRR1, message level is upregulated in the presence of the fungus. We propose that PYK10 restricts root colonization by P. indica, which results in the repression of defence responses and the upregulation of responses leading to a mutualistic interaction between the two symbiotic partners.
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Affiliation(s)
- Irena Sherameti
- Friedrich-Schiller-Universität Jena, Institut für Allgemeine Botanik und Pflanzenphysiologie, Dornburger Str. 159, 07743 Jena, Germany
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9
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Sue M, Yamazaki K, Yajima S, Nomura T, Matsukawa T, Iwamura H, Miyamoto T. Molecular and structural characterization of hexameric beta-D-glucosidases in wheat and rye. PLANT PHYSIOLOGY 2006; 141:1237-47. [PMID: 16751439 PMCID: PMC1533919 DOI: 10.1104/pp.106.077693] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
The wheat (Triticum aestivum) and rye (Secale cereale) beta-D-glucosidases hydrolyze hydroxamic acid-glucose conjugates, exist as different types of isozyme, and function as oligomers. In this study, three cDNAs encoding beta-D-glucosidases (TaGlu1a, TaGlu1b, and TaGlu1c) were isolated from young wheat shoots. Although the TaGlu1s share very high sequence homology, the mRNA level of Taglu1c was much lower than the other two genes in 48- and 96-h-old wheat shoots. The expression ratio of each gene was different between two wheat cultivars. Recombinant TaGlu1b expressed in Escherichia coli was electrophoretically distinct fromTaGlu1a and TaGlu1c. Furthermore, coexpression of TaGlu1a and TaGlu1b gave seven bands on a native-PAGE gel, indicating the formation of both homo- and heterohexamers. One distinctive property of the wheat and rye glucosidases is that they function as hexamers but lose activity when dissociated into smaller oligomers or monomers. The crystal structure of hexameric TaGlu1b was determined at a resolution of 1.8 A. The N-terminal region was located at the dimer-dimer interface and plays a crucial role in hexamer formation. Mutational analyses revealed that the aromatic side chain at position 378, which is located at the entrance to the catalytic center, plays an important role in substrate binding. Additionally, serine-464 and leucine-465 of TaGlu1a were shown to be critical in the relative specificity for DIMBOA-glucose (2-O-beta-D-glucopyranosyl-4-hydroxy-7-methoxy-1,4-benzoxazin-3-one) over DIBOA-glucose (7-demethoxy-DIMBOA-glucose).
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Affiliation(s)
- Masayuki Sue
- Department of Applied Biology and Chemistry , Tokyo University of Agriculture, Setagaya, Tokyo 156-8502, Japan.
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Choi DW, Jung J, Ha YI, Park HW, In DS, Chung HJ, Liu JR. Analysis of transcripts in methyl jasmonate-treated ginseng hairy roots to identify genes involved in the biosynthesis of ginsenosides and other secondary metabolites. PLANT CELL REPORTS 2005; 23:557-566. [PMID: 15538577 DOI: 10.1007/s00299-004-0845-4] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2004] [Revised: 06/28/2004] [Accepted: 06/29/2004] [Indexed: 05/24/2023]
Abstract
Methyl jasmonate (MeJA) treatment increases the levels of plant secondary metabolites, including ginsenosides, which are considered to be the main active compounds in ginseng (Panax ginseng C.A. Meyer). To create a ginseng gene resource that contains the genes involved in the biosynthesis of secondary metabolites, including ginsenosides, we generated 3,134 expression sequence tags (ESTs) from MeJA-treated ginseng hairy roots. These ESTs assembled into 370 clusters and 1,680 singletons. Genes yielding highly abundant transcripts were those encoding proteins involved in fatty acid desaturation, the defense response, and the biosynthesis of secondary metabolites. Analysis of the latter group revealed a number of genes that may be involved in the biosynthesis of ginsenosides, namely, oxidosqualene cyclase (OSC), cytochrome P450, and glycosyltransferase. A novel OSC gene was also identified by this analysis. RNA gel blot analysis confirmed that transcription of this OSC gene, along with squalene synthase (SS) and squalene epoxidase (SE) gene transcription, is increased by MeJA treatment. This ginseng EST data set will also provide important information on the genes that are involved in the biosynthesis of other secondary metabolites and the genes that are responsive to MeJA treatment.
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Affiliation(s)
- Dong-Woog Choi
- Eugentech, 52 Oun-Dong, Yusong, Taejon, 305-333, South Korea.
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Hara-Nishimura I, Matsushima R, Shimada T, Nishimura M. Diversity and formation of endoplasmic reticulum-derived compartments in plants. Are these compartments specific to plant cells? PLANT PHYSIOLOGY 2004; 136:3435-9. [PMID: 15542497 PMCID: PMC527142 DOI: 10.1104/pp.104.053876] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2004] [Revised: 10/09/2004] [Accepted: 10/09/2004] [Indexed: 05/18/2023]
Affiliation(s)
- Ikuko Hara-Nishimura
- Department of Botany, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
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Hara-Nishimura I, Matsushima R. A wound-inducible organelle derived from endoplasmic reticulum: a plant strategy against environmental stresses? CURRENT OPINION IN PLANT BIOLOGY 2003; 6:583-588. [PMID: 14611957 DOI: 10.1016/j.pbi.2003.09.015] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Endoplasmic reticulum (ER) is the most multitalented and adaptable compartment in plant cells. Recently, a wound-inducible organelle, which is derived from ER and designated the ER body, was found in Arabidopsis. Wounding and methyl jasmonate induce many ER bodies in rosette leaves, which have no ER bodies under normal conditions. In contrast, tender seedlings have a wide distribution of the ER bodies especially in all the epidermal cells, which are easily stressed by the external environment. The ER bodies play a role in a novel and unique type of endomembrane system that is involved in the response of plant cells to environmental stress and wounding.
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Matsushima R, Hayashi Y, Yamada K, Shimada T, Nishimura M, Hara-Nishimura I. The ER body, a novel endoplasmic reticulum-derived structure in Arabidopsis. PLANT & CELL PHYSIOLOGY 2003; 44:661-6. [PMID: 12881493 DOI: 10.1093/pcp/pcg089] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Plant cells develop various endoplasmic reticulum (ER)-derived structures with specific functions. The ER body, a novel ER-derived compartment in Arabidopsis, is a spindle-shaped structure (approximately 10 microm long and approximately 1 microm wide) that is surrounded by ribosomes. Similar structures were found in many Brassicaceae plants in the 1960s and 1970s, but their main components and biological functions have remained unknown. ER bodies can be visualized in transgenic Arabidopsis expressing the green fluorescent protein with an ER-retention signal. A large number of ER bodies are observed in cotyledons, hypocotyls and roots of seedlings, but very few are observed in rosette leaves. Recently nai1, a mutant that does not develop ER bodies in whole seedlings, was isolated. Analysis of the nai1 mutant reveals that a beta-glucosidase, called PYK10, is the main component of ER bodies. The putative biological function of PYK10 and the inducibility of ER bodies in rosette leaves by wound stress suggest that the ER body functions in the defense against herbivores.
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Affiliation(s)
- Ryo Matsushima
- Department of Botany, Graduate School of Science, Kyoto University, Kyoto, 606-8502 Japan
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14
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Matsushima R, Kondo M, Nishimura M, Hara-Nishimura I. A novel ER-derived compartment, the ER body, selectively accumulates a beta-glucosidase with an ER-retention signal in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2003; 33:493-502. [PMID: 12581307 DOI: 10.1046/j.1365-313x.2003.01636.x] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
The ER body is a novel compartment that is derived from endoplasmic reticulum (ER) in Arabidopsis. In contrast to whole seedlings which have a wide distribution of the ER bodies, rosette leaves have no ER bodies. Recently, we reported that wound stress induces the formation of many ER bodies in rosette leaves, suggesting that the ER body plays a role in the defense system of plants. ER bodies were visualized in transgenic plants (GFP-h) expressing green fluorescent protein (GFP) with an ER-retention signal, HDEL. These were concentrated in a 1000-g pellet (P1) of GFP-h plants. We isolated an Arabidopsis mutant, nai1, in which fluorescent ER bodies were hardly detected in whole plants. We found that a 65-kDa protein was specifically accumulated in the P1 fraction of GFP-h plants, but not in the P1 fraction of nai1 plants. N-terminal peptide sequencing revealed that the 65-kDa protein was a beta-glucosidase, PYK10, with an ER-retention signal, KDEL. Immunocytochemistry showed that PYK10 was localized in the ER bodies. Compared with the accumulation of GFP-HDEL, which was associated with both cisternal ER and ER bodies, the accumulation of PYK10 was much more specific to ER bodies. PYK10 was one of the major proteins in cotyledons, hypocotyls and roots of Arabidopsis seedlings, while PYK10 was not detected in rosette leaves that have no ER bodies. These findings indicated that PYK10 is the main component of ER bodies. It is possible that PYK10 produces defense compounds when plants are damaged by insects or wounding.
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Affiliation(s)
- Ryo Matsushima
- Department of Botany, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
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