101
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Zhou Y, Behrendt J, Sutherland AJ, Griffiths G. Synthetic molecular mimics of naturally occurring cyclopentenones exhibit antifungal activity towards pathogenic fungi. Microbiology (Reading) 2011; 157:3435-3445. [DOI: 10.1099/mic.0.052233-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The naturally occurring reactive electrophilic species 12-oxo-phytodienoic acid (12-oxo-PDA) is a potent antifungal agent, whereas the plant growth regulator jasmonic acid, which is synthesized from 12-oxo-PDA, is ineffective. To address what structural features of the molecule endow it with antifungal activity, we synthesized a series of molecular mimics of 12-oxo-PDA varying in the length of the alkyl chain at its C-4 ring position. The octyl analogue (4-octyl cyclopentenone) was the most effective at suppressing spore germination and subsequent mycelial growth of a range of fungal pathogens and was particularly effective against Cladosporium herbarum and Botrytis cinerea, with minimum fungicidal concentrations in the range 100–200 µM. Introduction of a carboxyl group to the end of the chain, mimicking natural fatty acids, markedly reduced antifungal efficacy. Electrolyte leakage, indicative of membrane perturbation, was evident in both C. herbarum and B. cinerea exposed to 4-octyl cyclopentenone. Lipid composition analysis of the fungal spores revealed that those species with a high oil content, namely Fusarium oxysporum and Alternaria brassicicola, were less sensitive to 4-octyl cyclopentenone. The comparable hydrophobicity of 4-octyl cyclopentenone and 12-oxo-PDA accounts for the similar spore suppression activity of these two compounds. The relative ease of synthesis of 4-octyl cyclopentenone makes it an attractive compound for potential use as an antifungal agent.
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Affiliation(s)
- Yi Zhou
- Chemical Engineering and Applied Chemistry, Aston University, UK
| | | | | | - Gareth Griffiths
- Chemical Engineering and Applied Chemistry, Aston University, UK
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102
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Bajsa J, Pan Z, Duke SO. Serine/threonine protein phosphatases: multi-purpose enzymes in control of defense mechanisms. PLANT SIGNALING & BEHAVIOR 2011; 6:1921-1925. [PMID: 22105028 PMCID: PMC3337179 DOI: 10.4161/psb.6.12.18146] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Depending on the threat to a plant, different pattern recognition receptors, such as receptor-like kinases, identify the stress and trigger action by appropriate defense response development. The plant immunity system primary response to these challenges is rapid accumulation of phytohormones, such as ethylene (ET), salicylic acid (SA), and jasmonic acid (JA) and its derivatives. These phytohormones induce further signal transduction and appropriate defenses against biotic threats. Phytohormones play crucial roles not only in the initiation of diverse downstream signaling events in plant defense but also in the activation of effective defenses through an essential process called signaling pathway crosstalk, a mechanism involved in transduction signals between two or more distinct, "linear signal transduction pathways simultaneously activated in the same cell."
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103
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Owiti J, Grossmann J, Gehrig P, Dessimoz C, Laloi C, Hansen MB, Gruissem W, Vanderschuren H. iTRAQ-based analysis of changes in the cassava root proteome reveals pathways associated with post-harvest physiological deterioration. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2011; 67:145-56. [PMID: 21435052 DOI: 10.1111/j.1365-313x.2011.04582.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The short storage life of harvested cassava roots is an important constraint that limits the full potential of cassava as a commercial food crop in developing countries. We investigated the molecular changes during physiological deterioration of cassava root after harvesting using isobaric tags for relative and absolute quantification (iTRAQ) of proteins in soluble and non-soluble fractions prepared during a 96 h post-harvest time course. Combining bioinformatic approaches to reduce information redundancy for unsequenced or partially sequenced plant species, we established a comprehensive proteome map of the cassava root and identified quantitatively regulated proteins. Up-regulation of several key proteins confirmed that physiological deterioration of cassava root after harvesting is an active process, with 67 and 170 proteins, respectively, being up-regulated early and later after harvesting. This included regulated proteins that had not previously been associated with physiological deterioration after harvesting, such as linamarase, glutamic acid-rich protein, hydroxycinnamoyl transferase, glycine-rich RNA binding protein, β-1,3-glucanase, pectin methylesterase, maturase K, dehydroascorbate reductase, allene oxide cyclase, and proteins involved in signal pathways. To confirm the regulation of these proteins, activity assays were performed for selected enzymes. Together, our results show that physiological deterioration after harvesting is a highly regulated complex process involving proteins that are potential candidates for biotechnology approaches to reduce such deterioration.
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Affiliation(s)
- Judith Owiti
- Department of Biology, Plant Biotechnology, Eidgenössische Technische Hochschule (ETH) Zurich, Universitätstraβe 2, 8092 Zurich, Switzerland
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104
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Schäfer M, Fischer C, Meldau S, Seebald E, Oelmüller R, Baldwin IT. Lipase activity in insect oral secretions mediates defense responses in Arabidopsis. PLANT PHYSIOLOGY 2011; 156:1520-34. [PMID: 21546453 PMCID: PMC3135923 DOI: 10.1104/pp.111.173567] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2011] [Accepted: 04/28/2011] [Indexed: 05/18/2023]
Abstract
How plants perceive herbivory is not yet well understood. We investigated early responses of the model plant Arabidopsis (Arabidopsis thaliana) to attack from the generalist grasshopper herbivore, Schistocerca gregaria (Caelifera). When compared with wounding alone, S. gregaria attack and the application of grasshopper oral secretions (GS) to puncture wounds elicited a rapid accumulation of various oxylipins, including 13-hydroperoxy octadecatrienoic acid, 12-oxo-phytodienoic acid (OPDA), jasmonic acid, and jasmonic acid-isoleucine. Additionally, GS increased cytosolic calcium levels, mitogen-activated protein kinase (MPK3 and MPK6) activity, and ethylene emission but not the accumulation of hydrogen peroxide. Although GS contain caeliferin A16:0, a putative elicitor of caeliferan herbivores, treatment with pure, synthetic caeliferin A16:0 did not induce any of the observed responses. With mutant plants, we demonstrate that the observed changes in oxylipin levels are independent of MPK3 and MPK6 activity but that MPK6 is important for the GS-induced ethylene release. Biochemical and pharmacological analyses revealed that the lipase activity of GS plays a central role in the GS-induced accumulation of oxylipins, especially OPDA, which could be fully mimicked by treating puncture wounds only with a lipase from Rhizopus arrhizus. GS elicitation increased the levels of OPDA-responsive transcripts. Because the oral secretions of most insects used to study herbivory-induced responses in Arabidopsis rapidly elicit similar accumulations of OPDA, we suggest that lipids containing OPDA (arabidopsides) play an important role in the activation of herbivory-induced responses.
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105
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Wu Q, Wu J, Sun H, Zhang D, Yu D. Sequence and expression divergence of the AOC gene family in soybean: insights into functional diversity for stress responses. Biotechnol Lett 2011; 33:1351-9. [PMID: 21626009 DOI: 10.1007/s10529-011-0585-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2011] [Accepted: 03/02/2011] [Indexed: 11/28/2022]
Abstract
As a signaling molecule, jasmonate plays a crucial role in orchestrating plant defense responses to a variety of biotic and abiotic stresses. Allene oxide cyclase (AOC: EC5.3.99.6) catalyzes the most important step in the jasmonate biosynthesis pathway. Six AOC genes were isolated from soybean, randomly distributed on chromosomes 1, 2, 8, 13, 18 and 19. The six AOC proteins were clustered into three groups with similarity values ranging from 55 to 95%. Real-time PCR revealed that the AOC genes have specific and complex expression patterns in multiple organs and under several stresses. Overexpression of GmAOC1 and GmAOC5 gene in transgenic tobacco, respectively enhanced tolerance to salinity and oxidative stresses. Such a large diversity within the AOC gene family might be an adaptive mechanism that developed during soybean genome evolution.
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Affiliation(s)
- Qian Wu
- National Center for Soybean Improvement, National Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing, China.
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106
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Chen Y, Pang Q, Dai S, Wang Y, Chen S, Yan X. Proteomic identification of differentially expressed proteins in Arabidopsis in response to methyl jasmonate. JOURNAL OF PLANT PHYSIOLOGY 2011; 168:995-1008. [PMID: 21377756 DOI: 10.1016/j.jplph.2011.01.018] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2010] [Revised: 01/06/2011] [Accepted: 01/10/2011] [Indexed: 05/25/2023]
Abstract
Jasmonates (JAs) are the well characterized fatty acid-derived cyclopentanone signals involved in the plant response to biotic and abiotic stresses. JAs have been shown to regulate many aspects of plant metabolism, including glucosinolate biosynthesis. Glucosinolates are natural plant products that function in defense against herbivores and pathogens. In this study, we applied a proteomic approach to gain insight into the physiological processes, including glucosinolate metabolism, in response to methyl jasmonate (MeJA). We identified 194 differentially expressed protein spots that contained proteins that participated in a wide range of physiological processes. Functional classification analysis showed that photosynthesis and carbohydrate anabolism were repressed after MeJA treatment, while carbohydrate catabolism was up-regulated. Additionally, proteins related to the JA biosynthesis pathway, stress and defense, and secondary metabolism were up-regulated. Among the differentially expressed proteins, many were involved in oxidative tolerance. The results indicate that MeJA elicited a defense response at the proteome level through a mechanism of redirecting growth-related metabolism to defense-related metabolism.
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Affiliation(s)
- Yazhou Chen
- Alkali Soil Natural Environmental Science Center, Northeast Forestry University/Key Laboratory of Saline-alkali Vegetation Ecology Restoration in Oil Field, Ministry of Education, Harbin 150040, China
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107
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Mielke K, Forner S, Kramell R, Conrad U, Hause B. Cell-specific visualization of jasmonates in wounded tomato and Arabidopsis leaves using jasmonate-specific antibodies. THE NEW PHYTOLOGIST 2011; 190:1069-1080. [PMID: 21561458 DOI: 10.1111/j.1469-8137.2010.03638.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Jasmonates are well-characterized signals in the development of plants and their response to abiotic and biotic stresses, such as touch and wounding by herbivores. A gap in our knowledge on jasmonate-induced processes, however, is the cellular localization of jasmonates. Here, a novel antibody-based approach was developed to visualize jasmonates in cross-sections of plant material. Antibodies raised in rabbits against BSA-coupled jasmonic acid (JA) are specific for JA, its methyl ester and isoleucine conjugate. They do not bind to 12-oxophytodienoic acid, 12-hydoxy-JA or coronatine. These antibodies were used in combination with newly established fixation and embedding methods. Jasmonates were rapidly and uniformly distributed within all cells near the site of damage of a mechanically wounded tomato (Solanum lycopersicum) leaf. Leaf tissue distally located to the wound site exhibited identical distribution, but had a lower signal intensity. The occurrence of jasmonates in all cell types of a wounded leaf was accompanied by transcript accumulation of early JA-induced genes visualized by in situ hybridization. With these new antibodies, a powerful tool is available to detect cell-specifically the occurrence of jasmonates in any jasmonate-dependent stress response or developmental process of plants.
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Affiliation(s)
- Kati Mielke
- Leibniz-Institut für Pflanzenbiochemie, D-06120 Halle, Germany
| | - Susanne Forner
- Leibniz-Institut für Pflanzenbiochemie, D-06120 Halle, Germany
| | - Robert Kramell
- Leibniz-Institut für Pflanzenbiochemie, D-06120 Halle, Germany
| | - Udo Conrad
- Leibniz-Institut für Pflanzengenetik und Kulturpflanzenforschung (IPK), D-06466 Gatersleben, Germany
| | - Bettina Hause
- Leibniz-Institut für Pflanzenbiochemie, D-06120 Halle, Germany
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108
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Dave A, Hernández ML, He Z, Andriotis VM, Vaistij FE, Larson TR, Graham IA. 12-oxo-phytodienoic acid accumulation during seed development represses seed germination in Arabidopsis. THE PLANT CELL 2011; 23:583-99. [PMID: 21335376 PMCID: PMC3077774 DOI: 10.1105/tpc.110.081489] [Citation(s) in RCA: 168] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2010] [Revised: 01/21/2011] [Accepted: 02/02/2011] [Indexed: 05/18/2023]
Abstract
Arabidopsis thaliana COMATOSE (CTS) encodes an ABC transporter involved in peroxisomal import of substrates for β-oxidation. Various cts alleles and mutants disrupted in steps of peroxisomal β-oxidation have previously been reported to exhibit a severe block on seed germination. Oxylipin analysis on cts, acyl CoA oxidase1 acyl CoA oxidase2 (acx1 acx2), and keto acyl thiolase2 dry seeds revealed that they contain elevated levels of 12-oxo-phytodienoic acid (OPDA), jasmonic acid (JA), and JA-Ile. Oxylipin and transcriptomic analysis showed that accumulation of these oxylipins occurs during late seed maturation in cts. Analysis of double mutants generated by crossing cts with mutants in the JA biosynthesis pathway indicate that OPDA, rather than JA or JA-Ile, contributes to the block on germination in cts seeds. We found that OPDA was more effective at inhibiting wild-type germination than was JA and that this effect was independent of CORONATINE INSENSITIVE1 but was synergistic with abscisic acid (ABA). Consistent with this, OPDA treatment increased ABA INSENSITIVE5 protein abundance in a manner that parallels the inhibitory effect of OPDA and OPDA+ABA on seed germination. These results demonstrate that OPDA acts along with ABA to regulate seed germination in Arabidopsis.
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109
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Zdyb A, Demchenko K, Heumann J, Mrosk C, Grzeganek P, Göbel C, Feussner I, Pawlowski K, Hause B. Jasmonate biosynthesis in legume and actinorhizal nodules. THE NEW PHYTOLOGIST 2011; 189:568-79. [PMID: 20964693 DOI: 10.1111/j.1469-8137.2010.03504.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Jasmonic acid (JA) is a plant signalling compound that has been implicated in the regulation of mutualistic symbioses. In order to understand the spatial distribution of JA biosynthetic capacity in nodules of two actinorhizal species, Casaurina glauca and Datisca glomerata, and one legume, Medicago truncatula, we determined the localization of allene oxide cyclase (AOC) which catalyses a committed step in JA biosynthesis. In all nodule types analysed, AOC was detected exclusively in uninfected cells. The levels of JA were compared in the roots and nodules of the three plant species. The nodules and noninoculated roots of the two actinorhizal species, and the root systems of M. truncatula, noninoculated or nodulated with wild-type Sinorhizobium meliloti or with mutants unable to fix nitrogen, did not show significant differences in JA levels. However, JA levels in all plant organs examined increased significantly on mechanical disturbance. To study whether JA played a regulatory role in the nodules of M. truncatula, composite plants containing roots expressing an MtAOC1-sense or MtAOC1-RNAi construct were inoculated with S. meliloti. Neither an increase nor reduction in AOC levels resulted in altered nodule formation. These data suggest that jasmonates are not involved in the development and function of root nodules.
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Affiliation(s)
- Anna Zdyb
- Georg-August-University Göttingen, Albrecht-von-Haller Institute for Plant Sciences, Department of Plant Biochemistry, 37077 Göttingen, Germany
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110
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Leon-Reyes A, Van der Does D, De Lange ES, Delker C, Wasternack C, Van Wees SCM, Ritsema T, Pieterse CMJ. Salicylate-mediated suppression of jasmonate-responsive gene expression in Arabidopsis is targeted downstream of the jasmonate biosynthesis pathway. PLANTA 2010; 232:1423-32. [PMID: 20839007 PMCID: PMC2957573 DOI: 10.1007/s00425-010-1265-z] [Citation(s) in RCA: 159] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2010] [Accepted: 08/17/2010] [Indexed: 05/18/2023]
Abstract
Jasmonates (JAs) and salicylic acid (SA) are plant hormones that play pivotal roles in the regulation of induced defenses against microbial pathogens and insect herbivores. Their signaling pathways cross-communicate providing the plant with a regulatory potential to finely tune its defense response to the attacker(s) encountered. In Arabidopsis thaliana, SA strongly antagonizes the jasmonic acid (JA) signaling pathway, resulting in the downregulation of a large set of JA-responsive genes, including the marker genes PDF1.2 and VSP2. Induction of JA-responsive marker gene expression by different JA derivatives was equally sensitive to SA-mediated suppression. Activation of genes encoding key enzymes in the JA biosynthesis pathway, such as LOX2, AOS, AOC2, and OPR3 was also repressed by SA, suggesting that the JA biosynthesis pathway may be a target for SA-mediated antagonism. To test this, we made use of the mutant aos/dde2, which is completely blocked in its ability to produce JAs because of a mutation in the ALLENE OXIDE SYNTHASE gene. Mutant aos/dde2 plants did not express the JA-responsive marker genes PDF1.2 or VSP2 in response to infection with the necrotrophic fungus Alternaria brassicicola or the herbivorous insect Pieris rapae. Bypassing JA biosynthesis by exogenous application of methyl jasmonate (MeJA) rescued this JA-responsive phenotype in aos/dde2. Application of SA suppressed MeJA-induced PDF1.2 expression to the same level in the aos/dde2 mutant as in wild-type Col-0 plants, indicating that SA-mediated suppression of JA-responsive gene expression is targeted at a position downstream of the JA biosynthesis pathway.
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Affiliation(s)
- Antonio Leon-Reyes
- Plant–Microbe Interactions, Department of Biology, Faculty of Science, Utrecht University, P.O. Box 80056, 3508 TB Utrecht, The Netherlands
- Universidad San Francisco de Quito (USFQ), Diego de Robles y Vía Interoceánica (Cumbaya), P.O. Box 17-1200-841, Quito, Ecuador
| | - Dieuwertje Van der Does
- Plant–Microbe Interactions, Department of Biology, Faculty of Science, Utrecht University, P.O. Box 80056, 3508 TB Utrecht, The Netherlands
| | - Elvira S. De Lange
- Plant–Microbe Interactions, Department of Biology, Faculty of Science, Utrecht University, P.O. Box 80056, 3508 TB Utrecht, The Netherlands
| | - Carolin Delker
- Leibniz Institute of Plant Biochemistry, 06120 Halle, Weinberg 3, Germany
| | - Claus Wasternack
- Leibniz Institute of Plant Biochemistry, 06120 Halle, Weinberg 3, Germany
| | - Saskia C. M. Van Wees
- Plant–Microbe Interactions, Department of Biology, Faculty of Science, Utrecht University, P.O. Box 80056, 3508 TB Utrecht, The Netherlands
| | - Tita Ritsema
- Plant–Microbe Interactions, Department of Biology, Faculty of Science, Utrecht University, P.O. Box 80056, 3508 TB Utrecht, The Netherlands
- Present Address: Amsterdam Molecular Therapeutics, Meibergdreef 61, 1100 DA Amsterdam, The Netherlands
| | - Corné M. J. Pieterse
- Plant–Microbe Interactions, Department of Biology, Faculty of Science, Utrecht University, P.O. Box 80056, 3508 TB Utrecht, The Netherlands
- Centre for BioSystems Genomics, P.O. Box 98, 6700 AB Wageningen, The Netherlands
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111
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Bilgin DD, Zavala JA, Zhu J, Clough SJ, Ort DR, DeLucia EH. Biotic stress globally downregulates photosynthesis genes. PLANT, CELL & ENVIRONMENT 2010; 33:1597-613. [PMID: 20444224 DOI: 10.1111/j.1365-3040.2010.02167.x] [Citation(s) in RCA: 315] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
To determine if damage to foliage by biotic agents, including arthropods, fungi, bacteria and viral pathogens, universally downregulates the expression of genes involved in photosynthesis, we compared transcriptome data from microarray experiments after twenty two different forms of biotic damage on eight different plant species. Transcript levels of photosynthesis light reaction, carbon reduction cycle and pigment synthesis genes decreased regardless of the type of biotic attack. The corresponding upregulation of genes coding for the synthesis of jasmonic acid and those involved in the responses to salicylic acid and ethylene suggest that the downregulation of photosynthesis-related genes was part of a defence response. Analysis of the sub-cellular targeting of co-expressed gene clusters revealed that the transcript levels of 84% of the genes that carry a chloroplast targeting peptide sequence decreased. The majority of these downregulated genes shared common regulatory elements, such as G-box (CACGTG), T-box (ACTTTG) and SORLIP (GCCAC) motifs. Strong convergence in the response of transcription suggests that the universal downregulation of photosynthesis-related gene expression is an adaptive response to biotic attack. We hypothesize that slow turnover of many photosynthetic proteins allows plants to invest resources in immediate defence needs without debilitating near term losses in photosynthetic capacity.
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Affiliation(s)
- Damla D Bilgin
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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112
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Kobayashi M, Seo S, Hirai K, Yamamoto-Katou A, Katou S, Seto H, Meshi T, Mitsuhara I, Ohashi Y. Silencing of WIPK and SIPK mitogen-activated protein kinases reduces tobacco mosaic virus accumulation but permits systemic viral movement in tobacco possessing the N resistance gene. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2010; 23:1032-41. [PMID: 20615114 DOI: 10.1094/mpmi-23-8-1032] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Infection of tobacco cultivars possessing the N resistance gene with Tobacco mosaic virus (TMV) results in confinement of the virus by necrotic lesions at the infection site. Although the mitogen-activated protein kinases WIPK and SIPK have been implicated in TMV resistance, evidence linking them directly to disease resistance is, as yet, insufficient. Viral multiplication was reduced slightly in WIPK- or SIPK-silenced plants but substantially in WIPK/SIPK-silenced plants, and was correlated with an increase in salicylic acid (SA) and a decrease in jasmonic acid (JA). Silencing of WIPK and SIPK in a tobacco cultivar lacking the N gene did not inhibit viral accumulation. The reduction in viral accumulation was attenuated by expressing a gene for an SA-degrading enzyme or by exogenously applying JA. Inoculation of lower leaves resulted in the systemic spread of TMV and formation of necrotic lesions in uninoculated upper leaves. These results suggested that WIPK and SIPK function to negatively regulate local resistance to TMV accumulation, partially through modulating accumulation of SA and JA in an N-dependent manner, but positively regulate systemic resistance.
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Affiliation(s)
- Michie Kobayashi
- National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, Japan
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113
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Wakuta S, Hamada S, Ito H, Matsuura H, Nabeta K, Matsui H. Identification of a beta-glucosidase hydrolyzing tuberonic acid glucoside in rice (Oryza sativa L.). PHYTOCHEMISTRY 2010; 71:1280-1288. [PMID: 20570296 DOI: 10.1016/j.phytochem.2010.04.025] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2009] [Revised: 03/01/2010] [Accepted: 04/27/2010] [Indexed: 05/29/2023]
Abstract
Tuberonic acid (TA) and its glucoside (TAG) have been isolated from potato (Solanum tuberosum L.) leaflets and shown to exhibit tuber-inducing properties. These compounds were reported to be biosynthesized from jasmonic acid (JA) by hydroxylation and subsequent glycosylation, and to be contained in various plant species. Here we describe the in vivo hydrolytic activity of TAG in rice. In this study, the TA resulting from TAG was not converted into JA. Tuberonic acid glucoside (TAG)-hydrolyzing beta-glucosidase, designated OsTAGG1, was purified from rice by six purification steps with an approximately 4300-fold purification. The purified enzyme migrated as a single band on native PAGE, but as two bands with molecular masses of 42 and 26 kDa on SDS-PAGE. Results from N-terminal sequencing and peptide mass fingerprinting of both polypeptides suggested that both bands were derived from a single polypeptide, which is a member of the glycosyl hydrolase family 1. In the native enzyme, the K(m) and V(max) values of TAG were 31.7 microM and 0.25 microkatal/mg protein, OsTAGG1 preferentially hydrolyzed TAG and methyl TAG. Here we report that OsTAGG1 is a specific beta-glucosidase hydrolyzing TAG, which releases the physiologically active TA.
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Affiliation(s)
- Shinji Wakuta
- Division of Applied Bioscience, Research Faculty of Agriculture, Hokkaido University, N-9, W-9, Kita-Ku, Sapporo 060-8589, Japan
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114
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Todd AT, Liu E, Polvi SL, Pammett RT, Page JE. A functional genomics screen identifies diverse transcription factors that regulate alkaloid biosynthesis in Nicotiana benthamiana. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2010; 62:589-600. [PMID: 20202168 DOI: 10.1111/j.1365-313x.2010.04186.x] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Biosynthesis of the alkaloid nicotine in Nicotiana species is induced by insect damage and jasmonate application. To probe the transcriptional regulation of the nicotine pathway, we constructed two subtracted cDNA libraries from methyl jasmonate (MeJA)-treated Nicotiana benthamiana roots directly in a viral vector suitable for virus-induced gene silencing (VIGS). Sequencing of cDNA inserts produced a data set of 3271 expressed sequence tags (ESTs; 1898 unigenes), which were enriched in jasmonate-responsive genes, and included 69 putative transcription factors (TFs). After a VIGS screen to determine their effect on nicotine metabolism, six TFs from three different TF families altered constitutive and MeJA-induced leaf nicotine levels. VIGS of a basic helix-loop-helix (bHLH) TF, NbbHLH3, and an auxin response factor TF, NbARF1, increased nicotine content compared with control plants; silencing the bHLH family members, NbbHLH1 and NbbHLH2, an ethylene response factor TF, NbERF1, and a homeobox domain-like TF, NbHB1, reduced nicotine levels. Transgenic N. benthamiana plants overexpressing NbbHLH1 or NbbHLH2 showed increased leaf nicotine levels compared with vector controls. RNAi silencing led to both reduced nicotine and decreased levels of transcript encoding of enzymes of the nicotine pathway. Electrophoretic mobility shift assays showed that recombinant NbbHLH1 and NbbHLH2 directly bind G-box elements identified from the putrescine N-methyltransferase promoter. We conclude that NbbHLH1 and NbbHLH2 function as positive regulators in the jasmonate activation of nicotine biosynthesis.
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Affiliation(s)
- Andrea T Todd
- Plant Biotechnology Institute, National Research Council of Canada, 110 Gymnasium Place, Saskatoon, SK, Canada S7N 0W9
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115
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Joyard J, Ferro M, Masselon C, Seigneurin-Berny D, Salvi D, Garin J, Rolland N. Chloroplast proteomics highlights the subcellular compartmentation of lipid metabolism. Prog Lipid Res 2010; 49:128-58. [DOI: 10.1016/j.plipres.2009.10.003] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2009] [Revised: 10/22/2009] [Accepted: 10/23/2009] [Indexed: 01/14/2023]
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116
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Rodríguez VM, Chételat A, Majcherczyk P, Farmer EE. Chloroplastic phosphoadenosine phosphosulfate metabolism regulates basal levels of the prohormone jasmonic acid in Arabidopsis leaves. PLANT PHYSIOLOGY 2010; 152:1335-45. [PMID: 20053710 PMCID: PMC2832275 DOI: 10.1104/pp.109.150474] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2009] [Accepted: 12/21/2009] [Indexed: 05/19/2023]
Abstract
Levels of the enzymes that produce wound response mediators have to be controlled tightly in unwounded tissues. The Arabidopsis (Arabidopsis thaliana) fatty acid oxygenation up-regulated8 (fou8) mutant catalyzes high rates of alpha -linolenic acid oxygenation and has higher than wild-type levels of the alpha -linolenic acid-derived wound response mediator jasmonic acid (JA) in undamaged leaves. fou8 produces a null allele in the gene SAL1 (also known as FIERY1 or FRY1). Overexpression of the wild-type gene product had the opposite effect of the null allele, suggesting a regulatory role of SAL1 acting in JA synthesis. The biochemical phenotypes in fou8 were complemented when the yeast (Saccharomyces cerevisiae) sulfur metabolism 3'(2'), 5'-bisphosphate nucleotidase MET22 was targeted to chloroplasts in fou8. The data are consistent with a role of SAL1 in the chloroplast-localized dephosphorylation of 3'-phospho-5'-adenosine phosphosulfate to 5'-adenosine phosphosulfate or in a closely related reaction (e.g. 3',5'-bisphosphate dephosphorylation). Furthermore, the fou8 phenotype was genetically suppressed in a triple mutant (fou8 apk1 apk2) affecting chloroplastic 3'-phospho-5'-adenosine phosphosulfate synthesis. These results show that a nucleotide component of the sulfur futile cycle regulates early steps of JA production and basal JA levels.
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Yoshii M, Yamazaki M, Rakwal R, Kishi-Kaboshi M, Miyao A, Hirochika H. The NAC transcription factor RIM1 of rice is a new regulator of jasmonate signaling. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2010; 61:804-15. [PMID: 20015061 DOI: 10.1111/j.1365-313x.2009.04107.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Jasmonates (JAs) are lipid-derived regulators that play crucial roles in both host immunity and development. We recently identified the NAC transcription factor RIM1 as a host factor involved in multiplication of rice dwarf virus (RDV). Here, we report that RIM1 functions as a transcriptional regulator of JA signaling and is degraded in response to JA treatment via a 26S proteasome-dependent pathway. Plants carrying rim1 mutations show a phenotype of root growth inhibition. The expression profiles of the mutants were significantly correlated with those of JA-treated wild-type plants without accumulation of endogenous JA, indicating that RIM1 functions as a component of JA signaling. The expression of genes encoding JA biosynthetic enzymes (lipoxygenase (LOX), allene oxide synthase 2 (AOS2) and OPDA reductase 7 (OPR7)) was up-regulated in the rim1 mutants under normal conditions, and a rapid and massive accumulation of endogenous JA was detected in the mutants after wounding. These results suggest that RIM1 may represent a new molecular link in jasmonate signaling, and may thereby provide new insights into the well-established coronatine-insensitive 1 (COI1)-Jasmonate ZIM-domain (JAZ) JA signaling pathway.
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Affiliation(s)
- Motoyasu Yoshii
- National Institute of Agrobiological Sciences, Tsukuba, Ibaraki 305-8602, Japan
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118
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Wasternack C, Kombrink E. Jasmonates: structural requirements for lipid-derived signals active in plant stress responses and development. ACS Chem Biol 2010; 5:63-77. [PMID: 20025249 DOI: 10.1021/cb900269u] [Citation(s) in RCA: 160] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Jasmonates are lipid-derived signals that mediate plant stress responses and development processes. Enzymes participating in biosynthesis of jasmonic acid (JA) (1, 2) and components of JA signaling have been extensively characterized by biochemical and molecular-genetic tools. Mutants of Arabidopsis and tomato have helped to define the pathway for synthesis of jasmonoyl-isoleucine (JA-Ile), the active form of JA, and to identify the F-box protein COI1 as central regulatory unit. However, details of the molecular mechanism of JA signaling have only recently been unraveled by the discovery of JAZ proteins that function in transcriptional repression. The emerging picture of JA perception and signaling cascade implies the SCF(COI1) complex operating as E3 ubiquitin ligase that upon binding of JA-Ile targets JAZ repressors for degradation by the 26S-proteasome pathway, thereby allowing the transcription factor MYC2 to activate gene expression. The fact that only one particular stereoisomer, (+)-7-iso-JA-l-Ile (4), shows high biological activity suggests that epimerization between active and inactive diastereomers could be a mechanism for turning JA signaling on or off. The recent demonstration that COI1 directly binds (+)-7-iso-JA-l-Ile (4) and thus functions as JA receptor revealed that formation of the ternary complex COI1-JA-Ile-JAZ is an ordered process. The pronounced differences in biological activity of JA stereoisomers also imply strict stereospecific control of product formation along the JA biosynthetic pathway. The pathway of JA biosynthesis has been unraveled, and most of the participating enzymes are well-characterized. For key enzymes of JA biosynthesis the crystal structures have been established, allowing insight into the mechanisms of catalysis and modes of substrate binding that lead to formation of stereospecific products.
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Affiliation(s)
- Claus Wasternack
- Department of Natural Product Biotechnology, Leibniz Institute of Plant Biochemistry, Weinberg 3, D-06120 Halle (Saale), Germany
| | - Erich Kombrink
- Department of Plant-Microbe Interactions, Max Planck Institute for Plant Breeding Research, Carl-von-Linne-Weg 10, D-50829 Cologne, Germany
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Widjaja I, Lassowskat I, Bethke G, Eschen-Lippold L, Long HH, Naumann K, Dangl JL, Scheel D, Lee J. A protein phosphatase 2C, responsive to the bacterial effector AvrRpm1 but not to the AvrB effector, regulates defense responses in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2010; 61:249-258. [PMID: 19843314 DOI: 10.1111/j.1365-313x.2009.04047.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Using a proteomics approach, a PP2C-type phosphatase (renamed PIA1, for PP2C induced by AvrRpm1) was identified that accumulates following infection by Pseudomonas syringae expressing the type III effector AvrRpm1, and subsequent activation of the corresponding plant NB-LRR disease resistance protein RPM1. No accumulation of PIA1 protein was seen following infection with P. syringae expressing AvrB, another type III effector that also activates RPM1, although PIA transcripts were observed. Accordingly, mutation of PIA1 resulted in enhanced RPM1 function in response to P. syringae pathover tomato (Pto) DC3000 (avrRpm1) but not to Pto DC3000 (avrB). Thus, PIA1 is a protein marker that distinguishes AvrRpm1- and AvrB-dependent activation of RPM1. AvrRpm1-induced expression of the pathogenesis-related genes PR1, PR2 and PR3, and salicylic acid accumulation were reduced in two pia1 mutants. By contrast, expression of other defense-related genes, including PR5 and PDF1.2 (plant defensin), was elevated in unchallenged pia1 mutants. Hence, PIA1 is required for AvrRpm1-induced responses, and confers dual (both positive and negative) regulation of defense gene expression.
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Affiliation(s)
- Ivy Widjaja
- Leibniz Institute of Plant Biochemistry, Weinberg 3, D-06120 Halle, Germany
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121
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Göbel C, Feussner I. Methods for the analysis of oxylipins in plants. PHYTOCHEMISTRY 2009; 70:1485-503. [PMID: 19735927 DOI: 10.1016/j.phytochem.2009.07.040] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2009] [Revised: 07/14/2009] [Accepted: 07/16/2009] [Indexed: 05/08/2023]
Abstract
Plant oxylipins comprise a highly diverse and complex class of molecules that are derived from lipid oxidation. The initial oxidation of unsaturated fatty acids may either occur by enzymatic or chemical reactions. A large variety of oxylipin classes are generated by an array of alternative reactions further converting hydroperoxy fatty acids. The structural diversity of oxylipins is further increased by their occurrence either as free fatty acid derivatives or as esters in complex lipids. Lipid peroxidation is common to all biological systems, appearing in developmentally regulated processes and as a response to environmental changes. The oxylipins formed may perform various biological roles; some of them have signaling functions. In order to elucidate the roles of oxylipins in a given biological context, comprehensive analytical assays are available for determining the oxylipin profiles of plant tissues. This review summarizes indirect methods to estimate the general peroxidation state of a sample and more sophisticated techniques for the identification, structure determination and quantification of oxylipins.
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Affiliation(s)
- Cornelia Göbel
- Georg-August-University, Albrecht-von-Haller-Institute for Plant Science, Department of Plant Biochemistry, D-37077 Göttingen, Germany
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122
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Schaller A, Stintzi A. Enzymes in jasmonate biosynthesis - structure, function, regulation. PHYTOCHEMISTRY 2009; 70:1532-8. [PMID: 19703696 DOI: 10.1016/j.phytochem.2009.07.032] [Citation(s) in RCA: 250] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2009] [Revised: 07/27/2009] [Accepted: 07/28/2009] [Indexed: 05/20/2023]
Abstract
Jasmonates are a growing class of lipid-derived signaling molecules with diverse functions ranging from the initiation of biotic and abiotic stress responses to the regulation of plant growth and development. Jasmonate biosynthesis originates from polyunsaturated fatty acids in chloroplast membranes. In a first lipoxygenase-catalyzed reaction molecular oxygen is introduced to yield their 13-hydroperoxy derivatives. These fatty acid hydroperoxides are converted by allene oxide synthase and allene oxide cyclase to 12-oxophytodienoic acid (OPDA) and dinor-OPDA, i.e. the first cyclic intermediates of the pathway. In the subsequent step, the characteristic cyclopentanone ring structure of jasmonates is established by OPDA reductase. Until recently, jasmonic acid has been viewed as the end product of the pathway and as the bioactive hormone. It becomes increasingly clear, however, that biological activity extends to and may even differ between the various jasmonic acid metabolites and conjugates as well as its biosynthetic precursors. It has also become clear that oxygenated fatty acids give rise to a vast variety of bioactive compounds including but not limited to jasmonates. Recent insights into the structure, function, and regulation of the enzymes involved in jasmonate biosynthesis help to explain how this variety is generated while specificity is maintained.
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Affiliation(s)
- Andreas Schaller
- Institute of Plant Physiology and Biotechnology, University of Hohenheim, D-70599 Stuttgart, Germany.
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123
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Koo AJ, Howe GA. The wound hormone jasmonate. PHYTOCHEMISTRY 2009; 70:1571-80. [PMID: 19695649 PMCID: PMC2784233 DOI: 10.1016/j.phytochem.2009.07.018] [Citation(s) in RCA: 229] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2009] [Revised: 07/13/2009] [Accepted: 07/14/2009] [Indexed: 05/17/2023]
Abstract
Plant tissues are highly vulnerable to injury by herbivores, pathogens, mechanical stress, and other environmental insults. Optimal plant fitness in the face of these threats relies on complex signal transduction networks that link damage-associated signals to appropriate changes in metabolism, growth, and development. Many of these wound-induced adaptive responses are triggered by de novo synthesis of the plant hormone jasmonate (JA). Recent studies provide evidence that JA mediates systemic wound responses through distinct cell autonomous and non-autonomous pathways. In both pathways, bioactive JAs are recognized by an F-box protein-based receptor system that couples hormone binding to ubiquitin-dependent degradation of transcriptional repressor proteins. These results provide a framework for understanding how plants recognize and respond to tissue injury.
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Affiliation(s)
- Abraham J.K. Koo
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824
| | - Gregg A. Howe
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824
- Corresponding author: Tel.: 1-517-355-5159; Fax: 1-517-353-9168. E-mail address:
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Koo AJK, Gao X, Jones AD, Howe GA. A rapid wound signal activates the systemic synthesis of bioactive jasmonates in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2009; 59:974-86. [PMID: 19473329 DOI: 10.1111/j.1365-313x.2009.03924.x] [Citation(s) in RCA: 269] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Jasmonic acid (JA) and its biologically active derivatives (bioactive JAs) perform a critical role in regulating plant responses to wound stress. The perception of bioactive JAs by the F-box protein COI1 triggers the SCF(COI1)/ubiquitin-dependent degradation of JASMONATE ZIM-DOMAIN (JAZ) proteins that repress the expression of JA-response genes. JA is required for many wound-inducible systemic defense responses, but little is known about the role of the hormone in long-distance signal relay between damaged and undamaged leaves. Here, we show that the wounding of Arabidopsis thaliana leaves results in the rapid (<5 min) accumulation of jasmonoyl-l-isoleucine (JA-Ile), the bioactive form of JA, in leaves distal to the wound site. The rapid systemic increase in JA-Ile preceded the onset of early transcriptional responses, and was associated with JAZ degradation. Wound-induced systemic production of JA-Ile required the JA biosynthetic enzyme 12-oxo-phytodienoic acid (OPDA) reductase 3 (OPR3) in undamaged responding leaves, but not in wounded leaves, and was largely dependent on the JA-conjugating enzyme JAR1. Interestingly, the wound-induced synthesis of JA/JA-Ile in systemic leaves was correlated with a rapid decline in OPDA levels. These results are consistent with a model in which a rapidly transmitted wound signal triggers the systemic synthesis of JA, which, upon conversion to JA-Ile, activates the expression of early response genes by the SCF(COI1)/JAZ pathway.
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Affiliation(s)
- Abraham J K Koo
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
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Wei Z, Hu W, Lin Q, Cheng X, Tong M, Zhu L, Chen R, He G. Understanding rice plant resistance to the Brown Planthopper (Nilaparvata lugens): a proteomic approach. Proteomics 2009; 9:2798-808. [PMID: 19405033 DOI: 10.1002/pmic.200800840] [Citation(s) in RCA: 110] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Engineering and breeding resistant plant varieties are the most effective and environmentally friendly ways to control agricultural pests and improve crop performance. However, the mechanism of plant resistance to pests is poorly understood. Here we used a quantitative mass-spectrometry-based proteomic approach for comparative analysis of expression profiles of proteins in rice leaf sheaths in responses to infestation by the brown planthopper (Nilaparvata lugens Stål, BPH), which is a serious rice crop pest. Proteins involved in multiple pathways showed significant changes in expression in response to BPH feeding, including jasmonic acid synthesis proteins, oxidative stress response proteins, beta-glucanases, protein; kinases, clathrin protein, glycine cleavage system protein, photosynthesis proteins and aquaporins. The corresponding genes of eight important proteins were further analyzed by quantitative RT-PCR. Proteomic and transcript responses that were related to wounding, oxidative and pathogen stress overlapped considerably between BPH-resistant (carrying the resistance gene BPH15) and susceptible rice lines. In contrast, proteins and genes related to callose metabolism remained unchanged and glycine cleavage system protein was up-regulated in the BPH-resistant lines, indicating that they have an efficient and specific defense mechanism. Our results provide new information about the interaction between rice and the BPH.
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Affiliation(s)
- Zhe Wei
- Key Laboratory of Ministry of Education for Plant Development Biology, College of Life Sciences, Wuhan University, Wuhan, P. R. China
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Bae H, Sicher RC, Kim MS, Kim SH, Strem MD, Melnick RL, Bailey BA. The beneficial endophyte Trichoderma hamatum isolate DIS 219b promotes growth and delays the onset of the drought response in Theobroma cacao. JOURNAL OF EXPERIMENTAL BOTANY 2009; 60:3279-95. [PMID: 19564160 PMCID: PMC2718224 DOI: 10.1093/jxb/erp165] [Citation(s) in RCA: 157] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2009] [Revised: 02/09/2009] [Accepted: 04/29/2009] [Indexed: 05/02/2023]
Abstract
Theobroma cacao (cacao) is cultivated in tropical climates and is exposed to drought stress. The impact of the endophytic fungus Trichoderma hamatum isolate DIS 219b on cacao's response to drought was studied. Colonization by DIS 219b delayed drought-induced changes in stomatal conductance, net photosynthesis, and green fluorescence emissions. The altered expression of 19 expressed sequence tags (ESTs) (seven in leaves and 17 in roots with some overlap) by drought was detected using quantitative real-time reverse transcription PCR. Roots tended to respond earlier to drought than leaves, with the drought-induced changes in expression of seven ESTs being observed after 7 d of withholding water. Changes in gene expression in leaves were not observed until after 10 d of withholding water. DIS 219b colonization delayed the drought-altered expression of all seven ESTs responsive to drought in leaves by > or = 3 d, but had less influence on the expression pattern of the drought-responsive ESTs in roots. DIS 219b colonization had minimal direct influence on the expression of drought-responsive ESTs in 32-d-old seedlings. By contrast, DIS 219b colonization of 9-d-old seedlings altered expression of drought-responsive ESTs, sometimes in patterns opposite of that observed in response to drought. Drought induced an increase in the concentration of many amino acids in cacao leaves, while DIS 219b colonization caused a decrease in aspartic acid and glutamic acid concentrations and an increase in alanine and gamma-aminobutyric acid concentrations. With or without exposure to drought conditions, colonization by DIS 219b promoted seedling growth, the most consistent effects being an increase in root fresh weight, root dry weight, and root water content. Colonized seedlings were slower to wilt in response to drought as measured by a decrease in the leaf angle drop. The primary direct effect of DIS 219b colonization was promotion of root growth, regardless of water status, and an increase in water content which it is proposed caused a delay in many aspects of the drought response of cacao.
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Affiliation(s)
- Hanhong Bae
- USDA-ARS-Beltsville Agricultural Research Center, Beltsville, MD 20705, USA
| | - Richard C. Sicher
- USDA-ARS-Beltsville Agricultural Research Center, Beltsville, MD 20705, USA
| | - Moon S. Kim
- USDA-ARS-Beltsville Agricultural Research Center, Beltsville, MD 20705, USA
| | - Soo-Hyung Kim
- College of Forest Resources, UW Botanic Gardens, University of Washington, Box 354115, Seattle, WA 98195, USA
| | - Mary D. Strem
- USDA-ARS-Beltsville Agricultural Research Center, Beltsville, MD 20705, USA
| | - Rachel L. Melnick
- Department of Plant Pathology, Pennsylvania State University, University Park, PA 16802, USA
| | - Bryan A. Bailey
- USDA-ARS-Beltsville Agricultural Research Center, Beltsville, MD 20705, USA
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Yang B, Jiang Y, Rahman MH, Deyholos MK, Kav NNV. Identification and expression analysis of WRKY transcription factor genes in canola (Brassica napus L.) in response to fungal pathogens and hormone treatments. BMC PLANT BIOLOGY 2009; 9:68. [PMID: 19493335 PMCID: PMC2698848 DOI: 10.1186/1471-2229-9-68] [Citation(s) in RCA: 110] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2008] [Accepted: 06/03/2009] [Indexed: 05/18/2023]
Abstract
BACKGROUND Members of plant WRKY transcription factor families are widely implicated in defense responses and various other physiological processes. For canola (Brassica napus L.), no WRKY genes have been described in detail. Because of the economic importance of this crop, and its evolutionary relationship to Arabidopsis thaliana, we sought to characterize a subset of canola WRKY genes in the context of pathogen and hormone responses. RESULTS In this study, we identified 46 WRKY genes from canola by mining the expressed sequence tag (EST) database and cloned cDNA sequences of 38 BnWRKYs. A phylogenetic tree was constructed using the conserved WRKY domain amino acid sequences, which demonstrated that BnWRKYs can be divided into three major groups. We further compared BnWRKYs to the 72 WRKY genes from Arabidopsis and 91 WRKY from rice, and we identified 46 presumptive orthologs of AtWRKY genes. We examined the subcellular localization of four BnWRKY proteins using green fluorescent protein (GFP) and we observed the fluorescent green signals in the nucleus only.The responses of 16 selected BnWRKY genes to two fungal pathogens, Sclerotinia sclerotiorum and Alternaria brassicae, were analyzed by quantitative real time-PCR (qRT-PCR). Transcript abundance of 13 BnWRKY genes changed significantly following pathogen challenge: transcripts of 10 WRKYs increased in abundance, two WRKY transcripts decreased after infection, and one decreased at 12 h post-infection but increased later on (72 h). We also observed that transcript abundance of 13/16 BnWRKY genes was responsive to one or more hormones, including abscisic acid (ABA), and cytokinin (6-benzylaminopurine, BAP) and the defense signaling molecules jasmonic acid (JA), salicylic acid (SA), and ethylene (ET). We compared these transcript expression patterns to those previously described for presumptive orthologs of these genes in Arabidopsis and rice, and observed both similarities and differences in expression patterns. CONCLUSION We identified a set of 13 BnWRKY genes from among 16 BnWRKY genes assayed, that are responsive to both fungal pathogens and hormone treatments, suggesting shared signaling mechanisms for these responses. This study suggests that a large number of BnWRKY proteins are involved in the transcriptional regulation of defense-related genes in response to fungal pathogens and hormone stimuli.
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Affiliation(s)
- Bo Yang
- Department of Agricultural, Food and Nutritional Science, Edmonton, Alberta T6G 2P5, Canada
| | - Yuanqing Jiang
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Muhammad H Rahman
- Department of Agricultural, Food and Nutritional Science, Edmonton, Alberta T6G 2P5, Canada
| | - Michael K Deyholos
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Nat NV Kav
- Department of Agricultural, Food and Nutritional Science, Edmonton, Alberta T6G 2P5, Canada
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Gális I, Gaquerel E, Pandey SP, Baldwin IT. Molecular mechanisms underlying plant memory in JA-mediated defence responses. PLANT, CELL & ENVIRONMENT 2009; 32:617-27. [PMID: 18657055 DOI: 10.1111/j.1365-3040.2008.01862.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Plants must respond to biotic and abiotic challenges to optimize their Darwinian fitness in nature. Many of these challenges occur repeatedly during a plant's lifetime, and their sequence and timing can profoundly influence the fitness outcome of a plant's response. The ability to perceive, store and recall previous stressful events is likely useful for efficient, rapid and cost-effective responses, but we know very little about the mechanisms involved. Using jasmonate-elicited anti-herbivore defence responses as an example, we consider how 'memories' of previous attacks could be created in (1) the biosynthetic processes involved in the generation of the oxylipin bursts elicited by herbivore attacks; (2) the perception of oxylipins and their transduction into cellular events by transcription factors and transcriptional activators; and (3) the role of small RNAs in the formation of long-term stress imprints in plants.
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Affiliation(s)
- Ivan Gális
- Department of Molecular Ecology, Max-Planck-Institute for Chemical Ecology, Hans-Knöll-Strasse 8, 07745 Jena, Germany
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Mosblech A, Feussner I, Heilmann I. Oxylipins: structurally diverse metabolites from fatty acid oxidation. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2009; 47:511-7. [PMID: 19167233 DOI: 10.1016/j.plaphy.2008.12.011] [Citation(s) in RCA: 262] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2008] [Revised: 11/13/2008] [Accepted: 12/08/2008] [Indexed: 05/19/2023]
Abstract
Oxylipins are lipophilic signaling molecules derived from the oxidation of polyunsaturated fatty acids. Initial fatty acid oxidation occurs mainly by the enzymatic or chemical formation of fatty acid hydroperoxides. An array of alternative reactions further converting fatty acid hydroperoxides gives rise to a multitude of oxylipin classes, many with reported signaling functions in plants. Oxylipins include the phytohormone, jasmonic acid, and a number of other molecules including hydroxy-, oxo- or keto-fatty acids or volatile aldehydes that may perform various biological roles as second messengers, messengers in inter-organismic signaling, or even as bactericidal agents. The structural diversity of oxylipins is further increased by esterification of the compounds in plastidial glycolipids, for instance the Arabidopsides, or by conjugation of oxylipins to amino acids or other metabolites. The enzymes involved in oxylipin metabolism are diverse and comprise a multitude of examples with interesting and unusual catalytic properties. In addition, the interplay of different subcellular compartments during oxylipin biosynthesis suggests complex mechanisms of regulation that are not well understood. This review aims at giving an overview of plant oxylipins and the multitude of enzymes responsible for their biosynthesis.
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Affiliation(s)
- Alina Mosblech
- Department of Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-University Göttingen, Göttingen, Germany
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Kaufmann K, Muiño JM, Jauregui R, Airoldi CA, Smaczniak C, Krajewski P, Angenent GC. Target genes of the MADS transcription factor SEPALLATA3: integration of developmental and hormonal pathways in the Arabidopsis flower. PLoS Biol 2009; 7:e1000090. [PMID: 19385720 PMCID: PMC2671559 DOI: 10.1371/journal.pbio.1000090] [Citation(s) in RCA: 332] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2008] [Accepted: 03/09/2009] [Indexed: 11/19/2022] Open
Abstract
The molecular mechanisms by which floral homeotic genes act as major developmental switches to specify the identity of floral organs are still largely unknown. Floral homeotic genes encode transcription factors of the MADS-box family, which are supposed to assemble in a combinatorial fashion into organ-specific multimeric protein complexes. Major mediators of protein interactions are MADS-domain proteins of the SEPALLATA subfamily, which play a crucial role in the development of all types of floral organs. In order to characterize the roles of the SEPALLATA3 transcription factor complexes at the molecular level, we analyzed genome-wide the direct targets of SEPALLATA3. We used chromatin immunoprecipitation followed by ultrahigh-throughput sequencing or hybridization to whole-genome tiling arrays to obtain genome-wide DNA-binding patterns of SEPALLATA3. The results demonstrate that SEPALLATA3 binds to thousands of sites in the genome. Most potential target sites that were strongly bound in wild-type inflorescences are also bound in the floral homeotic agamous mutant, which displays only the perianth organs, sepals, and petals. Characterization of the target genes shows that SEPALLATA3 integrates and modulates different growth-related and hormonal pathways in a combinatorial fashion with other MADS-box proteins and possibly with non-MADS transcription factors. In particular, the results suggest multiple links between SEPALLATA3 and auxin signaling pathways. Our gene expression analyses link the genomic binding site data with the phenotype of plants expressing a dominant repressor version of SEPALLATA3, suggesting that it modulates auxin response to facilitate floral organ outgrowth and morphogenesis. Furthermore, the binding of the SEPALLATA3 protein to cis-regulatory elements of other MADS-box genes and expression analyses reveal that this protein is a key component in the regulatory transcriptional network underlying the formation of floral organs. Most regulatory genes encode transcription factors, which modulate gene expression by binding to regulatory sequences of their target genes. In plants in particular, which genes are directly controlled by these transcription factors, and the molecular mechanisms of target gene recognition in vivo, are still largely unexplored. One of the best-understood developmental processes in plants is flower development. In different combinations, transcription factors of the MADS-box family control the identities of the different types of floral organs: sepals, petals, stamens, and carpels. Here, we present the first genome-wide analysis of binding sites of a MADS-box transcription factor in plants. We show that the MADS-domain protein SEPALLATA3 (SEP3) binds to the regulatory regions of thousands of potential target genes, many of which are also transcription factors. We provide insight into mechanisms of DNA recognition by SEP3, and suggest roles for other transcription factor families in SEP3 target gene regulation. In addition to effects on genes involved in floral organ identity, our data suggest that SEP3 binds to, and modulates, the transcription of target genes involved in hormonal signaling pathways. The key floral regulator SEPALLATA3 binds to the promoters of a large number of potential direct target genes to integrate different growth-related and hormonal pathways in flower development.
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Affiliation(s)
- Kerstin Kaufmann
- Business Unit Bioscience, Plant Research International, Wageningen, The Netherlands
| | - Jose M Muiño
- Institute of Plant Genetics, Polish Academy of Sciences, Poznań, Poland
| | | | - Chiara A Airoldi
- Centre for Plant Sciences, University of Leeds, Leeds, United Kingdom
| | - Cezary Smaczniak
- Business Unit Bioscience, Plant Research International, Wageningen, The Netherlands
- Centre for BioSystems Genomics (CBSG), Wageningen, The Netherlands
| | - Pawel Krajewski
- Institute of Plant Genetics, Polish Academy of Sciences, Poznań, Poland
| | - Gerco C Angenent
- Business Unit Bioscience, Plant Research International, Wageningen, The Netherlands
- Centre for BioSystems Genomics (CBSG), Wageningen, The Netherlands
- * To whom correspondence should be addressed. E-mail:
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131
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Molecular cloning, characterization and expression of a jasmonate biosynthetic pathway gene encoding allene oxide cyclase from Camptotheca acuminata. Biosci Rep 2009; 28:349-55. [PMID: 18847436 DOI: 10.1042/bsr20060001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
AOC (allene oxide cyclase; EC 5.3.99.6), an essential enzyme in jasmonic acid and its methyl ester biosynthesis, was cloned from Camptotheca acuminata (named as CaAOC), a native medicinal plant species in China. CaAOC had significant similarity at the amino-acid level with AOCs from other plant species. Comparison between the sequences of the full-length cDNA and genomic DNA of CaAOC revealed that the genomic DNA of CaAOC contained an 89-bp intron and a 240-bp intron. Southern-blot analysis indicated that CaAOC was a multiple-copy gene, and real-time quantitative PCR analysis showed that CaAOC was expressed constitutively in all organs tested, with the highest expression level in leaves. The results from treatment experiments using different signalling components, including methyl jasmonate, abscisic acid, salicylic acid and H(2)O(2), revealed that expression of CaAOC had a prominent diversity. Heavy metal (copper) significantly enhanced CaAOC expression, whereas wounding (induced by UV-B) was not so effective.
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132
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Pi Y, Jiang K, Cao Y, Wang Q, Huang Z, Li L, Hu L, Li W, Sun X, Tang K. Allene oxide cyclase from Camptotheca acuminata improves tolerance against low temperature and salt stress in tobacco and bacteria. Mol Biotechnol 2009; 41:115-22. [PMID: 18850307 DOI: 10.1007/s12033-008-9106-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2008] [Accepted: 09/08/2008] [Indexed: 10/21/2022]
Abstract
Allene oxide cyclase (AOC, E 5.3.99.6) is an essential enzyme in jasmonate (JA) biosynthetic pathway. An AOC gene (defined as CaAOC, Database Accession No. AY863428) had been isolated from Camptotheca acuminata in previous work. Real-time quantitative PCR analysis indicated that mRNA expression of CaAOC was induced by salt stress (120 mM NaCl) and low temperature (4 degrees C). In order to further investigate the role of AOC gene in the processes, CaAOC was introduced into tobacco via Agrobacterium tumefaciens, and the transgenic lines were subjected to the examination of tolerance against salt stress and low temperature. Under salt stress, the chlorophyll content in transgenic tobacco was higher than that of in the wild plants. The electrolyte leakage test revealed that transgenic tobacco plants were more resistant to low temperature over control. Furthermore, 5'-truncated CaAOC was inserted into pET30 and then expressed in Escherichia coli strain BL21DE3 (pLysS). Interestingly, the transformants could grow on 2YT agar containing 400 mM NaCl. Although these mechanisms are not clear yet, this study suggested that CaAOC could not only be a potential target gene in the engineering of plants and bacteria for improved endurance against salt stress, but also be quite useful in enhancing plant tolerance to cold.
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Affiliation(s)
- Yan Pi
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Morgan-Tan International Center for Life Sciences, Fudan-SJTU-Nottingham Plant Biotechnology R&D Center, Fudan University, 220 Handan Road, Shanghai, 200433, People's Republic of China
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133
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Okamoto H, Göbel C, Capper RG, Saunders N, Feussner I, Knight MR. The alpha-subunit of the heterotrimeric G-protein affects jasmonate responses in Arabidopsis thaliana. JOURNAL OF EXPERIMENTAL BOTANY 2009; 60:1991-2003. [PMID: 19342430 PMCID: PMC2682494 DOI: 10.1093/jxb/erp060] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2008] [Revised: 12/29/2008] [Accepted: 01/30/2009] [Indexed: 05/21/2023]
Abstract
Heterotrimeric G-proteins have been implicated in having a role in many plant signalling pathways. To understand further the role of G-proteins, a preliminary experiment was performed to assess the impact of the G alpha subunit loss-of-function mutation gpa1-1 on the Arabidopsis transcriptome. The analysis indicated that the G alpha subunit may play a role in response to jasmonic acid (JA). Consistent with this, G alpha mutants showed a reduced response to JA in inhibition of chlorophyll accumulation and root growth, whilst G alpha gain-of-function plants overexpressing G alpha showed the opposite phenotype. The levels of JA and related compounds were unaffected in the gpa1-1 mutant, as was autoregulation of the Allene Oxide Synthase (AOS) gene that encodes a key enzyme for JA biosynthesis. In contrast, further analyses using G alpha loss- and gain-of-function Arabidopsis lines indicated that G alpha positively modulates the expression of the Vegetative Storage Protein (VSP) gene. This indicates that the G alpha subunit regulates a subset of JA-regulated genes defining a branch point in this signalling pathway in Arabidopsis. Further analysis of the impact of G alpha loss of function upon the JA-regulated transcriptome using Arabidopsis full genome arrays indicated that up to 29% of genes that are >2-fold regulated by JA in the wild type are misregulated in the G alpha mutant. This supports the observation that a significant proportion of, but not all, JA-regulated gene expression is mediated by G alpha.
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Affiliation(s)
- Haruko Okamoto
- Department of Plant Sciences, University of Oxford, South Parks Road, Oxford OX1 3RB, UK.
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134
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Browse J. Jasmonate passes muster: a receptor and targets for the defense hormone. ANNUAL REVIEW OF PLANT BIOLOGY 2009; 60:183-205. [PMID: 19025383 DOI: 10.1146/annurev.arplant.043008.092007] [Citation(s) in RCA: 593] [Impact Index Per Article: 39.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The oxylipin jasmonate (JA) regulates many aspects of growth, development, and environmental responses in plants, particularly defense responses against herbivores and necrotrophic pathogens. Mutants of Arabidopsis helped researchers define the biochemical pathway for synthesis of jasmonoyl-isoleucine (JA-Ile), the active form of JA hormone, and demonstrated that JA is required for plant survival of insect and pathogen attacks and for plant fertility. Transcriptional profiling led to the discovery of the JASMONATE ZIM-DOMAIN (JAZ) proteins, which are repressors of JA signaling. JA-Ile relieves repression by promoting binding of the JAZ proteins to the F-box protein CORONATINE INSENSITIVE1 (COI1) and their subsequent degradation by the ubiquitination/26S-proteasome pathway. Although we now have a much better understanding of the molecular mechanism of JA action, many questions remain. Experimental answers to these questions will expand our knowledge of oxylipin signaling in plants and animals and will also provide new tools for efforts to improve crop protection and reproductive performance.
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Affiliation(s)
- John Browse
- Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164-6340, USA.
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135
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Andersson MX, Dörmann P. Chloroplast Membrane Lipid Biosynthesis and Transport. PLANT CELL MONOGRAPHS 2008. [DOI: 10.1007/978-3-540-68696-5_4] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
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136
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Koussevitzky S, Suzuki N, Huntington S, Armijo L, Sha W, Cortes D, Shulaev V, Mittler R. Ascorbate peroxidase 1 plays a key role in the response of Arabidopsis thaliana to stress combination. J Biol Chem 2008; 283:34197-203. [PMID: 18852264 DOI: 10.1074/jbc.m806337200] [Citation(s) in RCA: 227] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Within their natural habitat plants are subjected to a combination of different abiotic stresses, each with the potential to exacerbate the damage caused by the others. One of the most devastating stress combinations for crop productivity, which frequently occurs in the field, is drought and heat stress. In this study we conducted proteomic and metabolic analysis of Arabidopsis thaliana plants subjected to a combination of drought and heat stress. We identified 45 different proteins that specifically accumulated in Arabidopsis in response to the stress combination. These included enzymes involved in reactive oxygen detoxification, malate metabolism, and the Calvin cycle. The accumulation of malic enzyme during the combined stress corresponded with enhanced malic enzyme activity, a decrease in malic acid, and lower amounts of oxaloacetate, suggesting that malate metabolism plays an important role in the response of Arabidopsis to the stress combination. Cytosolic ascorbate peroxidase 1 (APX1) protein and mRNA accumulated during the stress combination. When exposed to heat stress combined with drought, an APX1-deficient mutant (apx1) accumulated more hydrogen peroxide and was significantly more sensitive to the stress combination than wild type. In contrast, mutants deficient in thylakoid or stromal/mitochondrial APXs were not more sensitive to the stress combination than apx1 or wild type. Our findings suggest that cytosolic APX1 plays a key role in the acclimation of plants to a combination of drought and heat stress.
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Affiliation(s)
- Shai Koussevitzky
- Department of Biochemistry and Molecular Biology, University of Nevada, Reno, Nevada 89557, USA
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137
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Hirano K, Aya K, Hobo T, Sakakibara H, Kojima M, Shim RA, Hasegawa Y, Ueguchi-Tanaka M, Matsuoka M. Comprehensive transcriptome analysis of phytohormone biosynthesis and signaling genes in microspore/pollen and tapetum of rice. PLANT & CELL PHYSIOLOGY 2008; 49:1429-50. [PMID: 18718932 PMCID: PMC2566925 DOI: 10.1093/pcp/pcn123] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2008] [Accepted: 08/18/2008] [Indexed: 05/18/2023]
Abstract
To investigate the involvement of phytohormones during rice microspore/pollen (MS/POL) development, endogenous levels of IAA, gibberellins (GAs), cytokinins (CKs) and abscisic acid (ABA) in the mature anther were analyzed. We also analyzed the global expression profiles of genes related to seven phytohormones, namely auxin, GAs, CKs, brassinosteroids, ethylene, ABA and jasmonic acids, in MS/POL and tapetum (TAP) using a 44K microarray combined with a laser microdissection technique (LM-array analysis). IAA and GA(4) accumulated in a much higher amount in the mature anther compared with the other tissues, while CKs and ABA did not. LM-array analysis revealed that sets of genes required for IAA and GA synthesis were coordinately expressed during the later stages of MS/POL development, suggesting that these genes are responsible for the massive accumulation of IAA and GA(4) in the mature anther. In contrast, genes for GA signaling were preferentially expressed during the early developmental stages of MS/POL and throughout TAP development, while their expression was down-regulated at the later stages of MS/POL development. In the case of auxin signaling genes, such mirror-imaged expression observed in GA synthesis and signaling genes was not observed. IAA receptor genes were mostly expressed during the late stages of MS/POL development, and various sets of AUX/IAA and ARF genes were expressed during the different stages of MS/POL or TAP development. Such cell type-specific expression profiles of phytohormone biosynthesis and signaling genes demonstrate the validity and importance of analyzing the expression of phytohormone-related genes in individual cell types independently of other cells/tissues.
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Affiliation(s)
- Ko Hirano
- Bioscience and Biotechnology Center, Nagoya University, Nagoya, 464-8601 Japan
| | - Koichiro Aya
- Bioscience and Biotechnology Center, Nagoya University, Nagoya, 464-8601 Japan
| | - Tokunori Hobo
- Bioscience and Biotechnology Center, Nagoya University, Nagoya, 464-8601 Japan
| | | | - Mikiko Kojima
- RIKEN Plant Science Center, Tsurumi, Yokohama, 230-0045 Japan
| | | | - Yasuko Hasegawa
- Bioscience and Biotechnology Center, Nagoya University, Nagoya, 464-8601 Japan
| | | | - Makoto Matsuoka
- Bioscience and Biotechnology Center, Nagoya University, Nagoya, 464-8601 Japan
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138
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Tamaoki M, Freeman JL, Marqusè L, Pilon-Smits EAH. New insights into the roles of ethylene and jasmonic acid in the acquisition of selenium resistance in plants. PLANT SIGNALING & BEHAVIOR 2008; 3:865-7. [PMID: 19704524 PMCID: PMC2634399 DOI: 10.4161/psb.3.10.6050] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2008] [Accepted: 04/07/2008] [Indexed: 05/07/2023]
Abstract
In a recent paper, we reported that both ethylene and jasmonic acid (JA) are important for selenium (Se) resistance in Arabidopsis.1 Elevated levels of reactive oxygen species were associated with ethylene and JA production in a Se-resistant Arabidopsis ecotype. Here, we further discuss the functions of these phytohormones, and their possible interactions, in plant Se resistance and -accumulation, placing our data in a broader perspective of other recently published papers.
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Affiliation(s)
- Masanori Tamaoki
- Biology Department; Colorado State University; Environmental Biology Division; National Institute for Environmental Studies; Graduate School of Life and Environmental Sciences; University of Tsukuba; Tsukuba, Ibaraki Japan; UMR de Biochimie et Physiologie Moléculaire des Plantes (B & PMP); Centre National de la Recherche Scientifique; Université Montpellier; Montpellier France
| | - JL Freeman
- Biology Department; Colorado State University; Environmental Biology Division; National Institute for Environmental Studies; Graduate School of Life and Environmental Sciences; University of Tsukuba; Tsukuba, Ibaraki Japan; UMR de Biochimie et Physiologie Moléculaire des Plantes (B & PMP); Centre National de la Recherche Scientifique; Université Montpellier; Montpellier France
| | - L Marqusè
- Biology Department; Colorado State University; Environmental Biology Division; National Institute for Environmental Studies; Graduate School of Life and Environmental Sciences; University of Tsukuba; Tsukuba, Ibaraki Japan; UMR de Biochimie et Physiologie Moléculaire des Plantes (B & PMP); Centre National de la Recherche Scientifique; Université Montpellier; Montpellier France
| | - EAH Pilon-Smits
- Biology Department; Colorado State University; Environmental Biology Division; National Institute for Environmental Studies; Graduate School of Life and Environmental Sciences; University of Tsukuba; Tsukuba, Ibaraki Japan; UMR de Biochimie et Physiologie Moléculaire des Plantes (B & PMP); Centre National de la Recherche Scientifique; Université Montpellier; Montpellier France
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139
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Yara A, Yaeno T, Hasegawa M, Seto H, Seo S, Kusumi K, Iba K. Resistance to Magnaporthe grisea in transgenic rice with suppressed expression of genes encoding allene oxide cyclase and phytodienoic acid reductase. Biochem Biophys Res Commun 2008; 376:460-5. [PMID: 18786507 DOI: 10.1016/j.bbrc.2008.08.157] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2008] [Accepted: 08/30/2008] [Indexed: 10/21/2022]
Abstract
Linolenic acid (18:3) and its derivative jasmonic acid (JA) are important molecules in disease resistance in many dicotyledonous plants. We have previously used 18:3- and JA-deficient rice (F78Ri) to investigate the roles of fatty acids and their derivatives in resistance to the blast fungus Magnaporthe grisea [A. Yara, T. Yaeno, J.-L. Montillet, M. Hasegawa, S. Seo, K. Kusumi, K. Iba, Enhancement of disease resistance to Magnaporthe grisea in rice by accumulation of hydroxy linoleic acid, Biochem. Biophys. Res. Commun. 370 (2008) 344-347; A. Yara, T. Yaeno, M. Hasegawa, H. Seto, J.-L. Montillet, K. Kusumi, S. Seo, K. Iba, Disease resistance against Magnaporthe grisea is enhanced in transgenic rice with suppression of omega-3 fatty acid desaturases, Plant Cell Physiol. 48 (2007) 1263-1274]. However, because F78Ri plants are suppressed in the first step of the JA biosynthetic pathway, we could not confirm the specific contribution of JA to disease resistance. In this paper, we generated two JA-deficient rice lines (AOCRi and OPRRi) with suppressed expression of the genes encoding allene oxide cyclase (AOC) and 12-oxo-phytodienoic acid reductase (OPR), which catalyze late steps in the JA biosynthetic pathway. The levels of disease resistance in the AOCRi and OPRRi lines were equal to that in wild-type plants. Our data suggest that resistance to M. grisea is not dependent on JA synthesis.
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Affiliation(s)
- Asanori Yara
- Department of Biology, Faculty of Sciences, Kyushu University, 6-10-1 Hakozaki, Higash-ku, Fukuoka 812-8581, Japan
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140
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Jiang K, Liao Z, Pi Y, Huang Z, Hou R, Cao Y, Wang Q, Sun X, Tang K. Molecular cloning and expression profile of a jasmonate biosynthetic pathway gene for allene oxide cyclase from Hyoscyamus niger. Mol Biol 2008. [DOI: 10.1134/s0026893308030059] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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141
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Schaller F, Zerbe P, Reinbothe S, Reinbothe C, Hofmann E, Pollmann S. The allene oxide cyclase family of Arabidopsis thaliana: localization and cyclization. FEBS J 2008; 275:2428-41. [PMID: 18393998 DOI: 10.1111/j.1742-4658.2008.06388.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Jasmonates are derived from oxygenated fatty acids (oxylipins) via the octadecanoid pathway and are characterized by a pentacyclic ring structure. They have regulatory functions as signaling molecules in plant development and adaptation to environmental stress. Recently, we solved the structure of allene oxide cyclase 2 (AOC2) of Arabidopsis thaliana, which is, together with the other three AOCs, a key enzyme in the biosynthesis of jasmonates, in that it releases the first cyclic and biologically active metabolite -- 12-oxo-phytodienoic acid (OPDA). On the basis of models for the bound substrate, 12,13(S)-epoxy-9(Z),11,15(Z)-octadecatrienoic acid, and the product, OPDA, we proposed that a conserved Glu promotes the reaction by anchimeric assistance. According to this hypothesis, the transition state with a pentadienyl carbocation and an oxyanion is stabilized by a strongly bound water molecule and favorable pi-pi interactions with aromatic residues in the cavity. Stereoselectivity results from steric restrictions to the necessary substrate isomerizations imposed by the protein environment. Here, site-directed mutagenesis was used to explore and verify the proposed reaction mechanism. In a comparative analysis of the AOC family from A. thaliana involving enzymatic characterization, in vitro import, and transient expression of AOC-enhanced green fluorescent protein fusion proteins for analysis of subcellular targeting, we demonstrate that all four AOC isoenzymes may contribute to jasmonate biosynthesis, as they are all located in chloroplasts and, in concert with the allene oxide synthase, they are all able to convert 13(S)-hydroperoxy-9(Z),11(E),15(Z)-octadecatrienoic acid into enantiomerically pure cis(+)-OPDA.
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Affiliation(s)
- Florian Schaller
- Lehrstuhl für Pflanzenphysiologie, Ruhr-Universität Bochum, Germany
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142
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Chung HS, Koo AJK, Gao X, Jayanty S, Thines B, Jones AD, Howe GA. Regulation and function of Arabidopsis JASMONATE ZIM-domain genes in response to wounding and herbivory. PLANT PHYSIOLOGY 2008; 146:952-64. [PMID: 18223147 PMCID: PMC2259048 DOI: 10.1104/pp.107.115691] [Citation(s) in RCA: 319] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2007] [Accepted: 01/21/2008] [Indexed: 05/18/2023]
Abstract
Jasmonate (JA) and its amino acid conjugate, jasmonoyl-isoleucine (JA-Ile), play important roles in regulating plant defense responses to insect herbivores. Recent studies indicate that JA-Ile promotes the degradation of JASMONATE ZIM-domain (JAZ) transcriptional repressors through the activity of the E(3) ubiquitin-ligase SCF(COI1). Here, we investigated the regulation and function of JAZ genes during the interaction of Arabidopsis (Arabidopsis thaliana) with the generalist herbivore Spodoptera exigua. Most members of the JAZ gene family were highly expressed in response to S. exigua feeding and mechanical wounding. JAZ transcript levels increased within 5 min of mechanical tissue damage, coincident with a large (approximately 25-fold) rise in JA and JA-Ile levels. Wound-induced expression of JAZ and other CORONATINE-INSENSITIVE1 (COI1)-dependent genes was not impaired in the jar1-1 mutant that is partially deficient in the conversion of JA to JA-Ile. Experiments performed with the protein synthesis inhibitor cycloheximide provided evidence that JAZs, MYC2, and genes encoding several JA biosynthetic enzymes are primary response genes whose expression is derepressed upon COI1-dependent turnover of a labile repressor protein(s). We also show that overexpression of a modified form of JAZ1 (JAZ1Delta3A) that is stable in the presence of JA compromises host resistance to feeding by S. exigua larvae. These findings establish a role for JAZ proteins in the regulation of plant anti-insect defense, and support the hypothesis that JA-Ile and perhaps other JA derivatives activate COI1-dependent wound responses in Arabidopsis. Our results also indicate that the timing of JA-induced transcription in response to wounding is more rapid than previously realized.
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Affiliation(s)
- Hoo Sun Chung
- Department of Energy Plant Research Laboratory , Michigan State University, East Lansing, MI 48824, USA
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143
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Hofmann E, Pollmann S. Molecular mechanism of enzymatic allene oxide cyclization in plants. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2008; 46:302-8. [PMID: 18272375 DOI: 10.1016/j.plaphy.2007.12.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2007] [Indexed: 05/01/2023]
Abstract
Jasmonates, a collective term combining both jasmonic acid (JA) and related derivatives, are ubiquitously distributed in the plant kingdom. They are characterized as lipid-derived signal molecules which mediate a plethora of physiological functions, in particular stress responses, male fertility, and a multitude of developmental processes. In the course of JA biosynthesis, the first oxylipin with signal character, cis-(+)-12-oxo-phytodienoic acid (OPDA), is produced in a cyclization reaction catalyzed by allene oxide cyclase (AOC). This enzyme-catalyzed ring closure is of particular importance, as it warrants the enantiomeric structure at the cyclopentenone ring which in the end results in the only bioactive JA enantiomer, cis-(+)-JA. In this review, we focus on the structural and molecular mechanisms underlying the above mentioned cyclization reaction. In this context, we will discuss the crystal structure of AOC2 of Arabidopsis thaliana with respect to putative binding sites of the instable substrate, 12,13-epoxy-9(Z),11,15(Z)-octadecatrienoic acid (12,13-EOT), as well as possible intermolecular rearrangements during the cyclization reaction.
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Affiliation(s)
- Eckhard Hofmann
- Biophysics, Department of Biology and Biotechnology, Ruhr-University Bochum, Universitaetsstrasse 150, D-44801 Bochum, Germany.
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144
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Mosblech A, König S, Stenzel I, Grzeganek P, Feussner I, Heilmann I. Phosphoinositide and inositolpolyphosphate signalling in defense responses of Arabidopsis thaliana challenged by mechanical wounding. MOLECULAR PLANT 2008; 1:249-61. [PMID: 19825537 DOI: 10.1093/mp/ssm028] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Various biochemical signals are implicated in Arabidopsis wound signalling, including jasmonic acid (JA), salicylic acid, auxin, and Ca2+. Here, we report on cross-talk of phytohormones with phosphoinositide signals not previously implicated in plant wound responses. Within 30 min of mechanical wounding of Arabidopsis rosette-leaves, the levels of the lipid-derived soluble inositolpolyphosphate, inositol 1,4,5-trisphosphate (InsP(3)), increased four to five-fold. Concomitantly, the precursor lipids, phosphatidylinositol 4,5-bisphosphate, phosphatidylinositol 4-phosphate and phosphatidylinositol transiently depleted, followed by re-synthesis after 30-60 min of stimulation. Increased InsP(3) levels with wounding coincided with JA increases over the first hours of stimulation. In dde2-2-mutant plants deficient in JA biosynthesis, no InsP(3) increase was observed upon wounding, indicating that JA was required for InsP(3) formation, and InsP(3) levels increased in wild-type plants challenged with sorbitol, increasing endogenous JA levels. In InsP 5-ptase plants with attenuated phosphoinositide signalling, the induction of wounding-inducible genes was diminished compared with wild-type plants, suggesting a role for phosphoinositide signalling in mediating plant wound responses. The gene-expression patterns suggest that phosphoinositides contribute to both JA-dependent and JA-independent aspects of wound signalling. Weight gain of Plutella xylostella caterpillars feeding on InsP 5-ptase plants was increased compared with that of caterpillars feeding on wild-type plants. The ecophysiological relevance of phosphoinositide signals in plant defense responses to herbivory is discussed in light of recent findings of inositolpolyphosphate involvement in phytohormone-receptor function.
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Affiliation(s)
- Alina Mosblech
- Department of Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-University Göttingen, Justus-von-Liebig-Weg 11, 37077 Göttingen, Germany
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145
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Cooperation and Functional Diversification of Two Closely Related Galactolipase Genes for Jasmonate Biosynthesis. Dev Cell 2008; 14:183-92. [DOI: 10.1016/j.devcel.2007.11.010] [Citation(s) in RCA: 136] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2007] [Revised: 09/18/2007] [Accepted: 11/13/2007] [Indexed: 11/20/2022]
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146
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Kienow L, Schneider K, Bartsch M, Stuible HP, Weng H, Miersch O, Wasternack C, Kombrink E. Jasmonates meet fatty acids: functional analysis of a new acyl-coenzyme A synthetase family from Arabidopsis thaliana. JOURNAL OF EXPERIMENTAL BOTANY 2008; 59:403-19. [PMID: 18267944 DOI: 10.1093/jxb/erm325] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Arabidopsis thaliana contains a large number of genes encoding carboxylic acid-activating enzymes, including long-chain fatty acyl-CoA synthetase (LACS), 4-coumarate:CoA ligases (4CL), and proteins closely related to 4CLs with unknown activities. The function of these 4CL-like proteins was systematically explored by applying an extensive substrate screen, and it was uncovered that activation of fatty acids is the common feature of all active members of this protein family, thereby defining a new group of fatty acyl-CoA synthetase, which is distinct from the known LACS family. Significantly, four family members also displayed activity towards different biosynthetic precursors of jasmonic acid (JA), including 12-oxo-phytodienoic acid (OPDA), dinor-OPDA, 3-oxo-2(2'-[Z]-pentenyl)cyclopentane-1-octanoic acid (OPC-8), and OPC-6. Detailed analysis of in vitro properties uncovered significant differences in substrate specificity for individual enzymes, but only one protein (At1g20510) showed OPC-8:CoA ligase activity. Its in vivo function was analysed by transcript and jasmonate profiling of Arabidopsis insertion mutants for the gene. OPC-8:CoA ligase expression was activated in response to wounding or infection in the wild type but was undetectable in the mutants, which also exhibited OPC-8 accumulation and reduced levels of JA. In addition, the developmental, tissue- and cell-type specific expression pattern of the gene, and regulatory properties of its promoter were monitored by analysing promoter::GUS reporter lines. Collectively, the results demonstrate that OPC-8:CoA ligase catalyses an essential step in JA biosynthesis by initiating the beta-oxidative chain shortening of the carboxylic acid side chain of its precursors, and, in accordance with this function, the protein is localized in peroxisomes.
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Affiliation(s)
- Lucie Kienow
- Max Planck Institute for Plant Breeding Research, Department of Plant-Microbe Interactions, Carl-von-Linné-Weg 10, D-50829 Köln, Germany
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147
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Andersson MX, Dörmann P. Chloroplast Membrane Lipid Biosynthesis and Transport. PLANT CELL MONOGRAPHS 2008. [DOI: 10.1007/7089_2008_18] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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148
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Tretner C, Huth U, Hause B. Mechanostimulation of Medicago truncatula leads to enhanced levels of jasmonic acid. JOURNAL OF EXPERIMENTAL BOTANY 2008; 59:2847-56. [PMID: 18540020 PMCID: PMC2486479 DOI: 10.1093/jxb/ern145] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2008] [Accepted: 04/28/2008] [Indexed: 05/18/2023]
Abstract
Wounding of plants leads to endogenous rise of jasmonic acid (JA) accompanied with the expression of a distinct set of genes. Among them are those coding for the allene oxide cyclase (AOC) that catalyses a regulatory step in JA biosynthesis, and for 1-deoxy-D-xylulose 5-phosphate synthase 2 (DXS2), an enzyme involved in isoprenoid biosynthesis. To address the question how roots and shoots of Medicago truncatula respond to mechanostimulation and wounding, M. truncatula plants were analysed in respect to JA levels as well as MtAOC1 and MtDXS2-1 transcript accumulation. Harvest-caused mechanostimulation resulted in a strong, but transient increase in JA level in roots and shoots followed by a transient increase in MtAOC1 transcript accumulation. Additional wounding of either shoots or roots led to further increased JA and MtAOC1 transcript levels in shoots, but not in roots. In situ hybridization revealed a cell-specific transcript accumulation of MtAOC1 after mechanostimulation in companion cells of the vascular tissue of the stem. AOC protein, however, was found to occur constitutively in vascular bundles. Further, transcript accumulation of MtDXS2-1 was similar to that of MtAOC1 in shoots, but its transcript levels were not enhanced in roots. Repeated touching of shoots increased MtAOC1 transcript levels and led to significantly shorter shoots and increased biomass. In conclusion, M. truncatula plants respond very sensitively to mechanostimulation with enhanced JA levels and altered transcript accumulation, which might contribute to the altered phenotype after repeated touching of plants.
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149
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Kourtchenko O, Andersson MX, Hamberg M, Brunnström A, Göbel C, McPhail KL, Gerwick WH, Feussner I, Ellerström M. Oxo-phytodienoic acid-containing galactolipids in Arabidopsis: jasmonate signaling dependence. PLANT PHYSIOLOGY 2007; 145:1658-69. [PMID: 17951463 PMCID: PMC2151682 DOI: 10.1104/pp.107.104752] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2007] [Accepted: 10/09/2007] [Indexed: 05/17/2023]
Abstract
The jasmonate family of phytohormones, as represented by 12-oxo-phytodienoic acid (OPDA), dinor-phytodienoic acid (dn-OPDA), and jasmonic acid in Arabidopsis (Arabidopsis thaliana), has been implicated in a vast array of different developmental processes and stress responses. Recent reports indicate that OPDA and dn-OPDA occur not only as free acids in Arabidopsis, but also as esters with complex lipids, so-called arabidopsides. Recently, we showed that recognition of the two bacterial effector proteins AvrRpm1 and AvrRpt2 induced high levels of a molecule consisting of two OPDAs and one dn-OPDA esterified to a monogalactosyl diacylglycerol moiety, named arabidopside E. In this study, we demonstrate that the synthesis of arabidopsides is mainly independent of the prokaryotic lipid biosynthesis pathway in the chloroplast, and, in addition to what previously has been reported, arabidopside E as well as an all-OPDA analog, arabidopside G, described here accumulated during the hypersensitive response and in response to wounding. We also show that different signaling pathways lead to the formation of arabidopsides during the hypersensitive response and the wounding response, respectively. However, the formation of arabidopsides during both responses is dependent on an intact jasmonate signaling pathway. Additionally, we report inhibition of growth of the fungal necrotrophic pathogen Botrytis cinerea and in planta release of free jasmonates in a time frame that overlaps with the observed reduction of arabidopside levels. Thus, arabidopsides may have a dual function: as antipathogenic substances and as storage compounds that allow the slow release of free jasmonates.
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Affiliation(s)
- Olga Kourtchenko
- Department of Plant and Environmental Sciences, Göteborg University, SE-405 30 Gothenburg, Sweden
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150
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Cenzano A, Abdala G, Hause B. Cytochemical immuno-localization of allene oxide cyclase, a jasmonic acid biosynthetic enzyme, in developing potato stolons. JOURNAL OF PLANT PHYSIOLOGY 2007; 164:1449-56. [PMID: 17223227 DOI: 10.1016/j.jplph.2006.10.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2006] [Revised: 10/13/2006] [Accepted: 10/17/2006] [Indexed: 05/13/2023]
Abstract
The involvement of jasmonates in the tuber development has been proved by the presence of many of these compounds in potato stolons, modification of their levels during the transition of the stolon into tuber, and induction of cell expansion upon exogenous jasmonates treatment. However, to date there is only little evidence of the presence of the jasmonic acid-biosynthetic enzymes in stolons or young tubers. As allene oxide cyclase represents the major control point for jasmonic acid biosynthesis, we studied the occurrence of allene oxide cyclase by immunological approaches in the early stages of tuber formation. In developing stolons, allene oxide cyclase as well as lipoxygenase were clearly detectable, but their levels did not change during development. Jasmonic acid treatment for 24h, however, increased lipoxygenase and allene oxide cyclase protein levels in both developmental stages analyzed. In longitudinal sections of stolons of stages 1 and 2, allene oxide cyclase and lipoxygenase occurred in the apex and along the stolon axis. Allene oxide cyclase was clearly detectable in epidermal, cortical and pith parenchymatic cells, showing the highest levels in vascular tissues surrounding cells. Lipoxygenase was mainly located in the parenchymatic cortex cells. The occurrence of allene oxide cyclase in stolons together with the previous identification of jasmonates from developing stolons reveals that these organs are capable to synthesize and metabolize jasmonates.
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Affiliation(s)
- Ana Cenzano
- Universidad Nacional de Río Cuarto, Departamento de Ciencias Naturales, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Ruta 36, Km 601, CP 5800 Río Cuarto, Córdoba, Argentina
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