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Berg RH, Kahn TW, McCarville MT, Williams J, Czymmek KJ, Daum J. Immunolocalization and Ultrastructure Show Ingestion of Cry Protein Expressed in Glycine max by Heterodera glycines and Its Mode of Action. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2024:MPMI02240021R. [PMID: 39159465 DOI: 10.1094/mpmi-02-24-0021-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/21/2024]
Abstract
Great interest exists in developing a transgenic trait that controls the economically important soybean (Glycine max) pest, soybean cyst nematode (SCN, Heterodera glycines), due to its adaptation to native resistance. Soybean plants expressing the Bacillus thuringiensis delta-endotoxin, Cry14Ab, were recently demonstrated to control SCN in both growth chamber and field testing. In that communication, ingestion of the Cry14Ab toxin by SCN second stage juveniles (J2s) was demonstrated using fluorescently labeled Cry14Ab in an in vitro assay. Here, we show that consistent with expectations for a Cry toxin, Cry14Ab has a mode of action unique from the native resistance sources Peking and PI 88788. Further, we demonstrate in planta the ingestion and localization of the Cry14Ab toxin in the midgut of nematodes feeding on roots expressing Cry14Ab using immunogold labeling and transmission electron microscopy. We observed immunolocalization of the toxin and resulting intestinal damage primarily in the microvillus-like structure (MvL)-containing region of the midgut intestine but not in nematodes feeding on roots lacking toxin. This demonstrated that Cry14Ab was taken up by the J2 SCN, presumably through the feeding tube within the plant root cell that serves as its feeding site. This suggests that relatively large proteins can be taken up through the feeding tube. Electron microscopy showed that Cry14Ab caused lysis of the midgut MvL membrane and eventual degradation of the MvL and the lysate, forming particulate aggregates. The accumulated electron-dense aggregate in the posterior midgut intestine was not observed in SCN in nonCry14Ab-expressing plants. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
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Affiliation(s)
- R Howard Berg
- Advanced Bioimaging Laboratory, Donald Danforth Plant Science Center, St. Louis, MO 63132, U.S.A
| | | | | | - Jayme Williams
- BASF Corporation, Research Triangle Park, NC 27709, U.S.A
| | - Kirk J Czymmek
- Advanced Bioimaging Laboratory, Donald Danforth Plant Science Center, St. Louis, MO 63132, U.S.A
| | - Julia Daum
- BASF Corporation, Research Triangle Park, NC 27709, U.S.A
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Liu X, Mitchum MG. Evaluation of Chemical-Inducible Gene Expression Systems for Beet Cyst Nematode Infection Assays in Arabidopsis thaliana. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2024; 37:611-618. [PMID: 38862124 DOI: 10.1094/mpmi-04-24-0042-ta] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2024]
Abstract
Cyst nematodes co-opt plant developmental programs for the establishment of a permanent feeding site called a syncytium in plant roots. In recent years, the role of plant developmental genes in syncytium formation has gained much attention. One main obstacle in studying the function of development-related genes in syncytium formation is that mutation or ectopic expression of such genes can cause pleiotropic phenotypes, making it difficult to interpret nematode-related phenotypes or, in some cases, impossible to carry out infection assays due to aberrant root development. Here, we tested three commonly used inducible gene expression systems for their application in beet cyst nematode infection assays of the model plant Arabidopsis thaliana. We found that even a low amount of ethanol diminished nematode development, deeming the ethanol-based system unsuitable for use in cyst nematode infection assays, whereas treatment with estradiol or dexamethasone did not negatively affect cyst nematode viability. Dose and time course responses showed that in both systems, a relatively low dose of inducer (1 μM) is sufficient to induce high transgene expression within 24 h of treatment. Transgene expression peaked at 3 to 5 days post-induction and began to decline thereafter, providing a perfect window for inducible transgenes to interfere with syncytium establishment while minimizing any adverse effects on root development. These results indicate that both estradiol- and dexamethasone-based inducible gene expression systems are suitable for cyst nematode infection assays. The employment of such systems provides a powerful tool to investigate the function of essential plant developmental genes in syncytium formation. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
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Affiliation(s)
- Xunliang Liu
- Department of Plant Pathology and Institute of Plant Breeding, Genetics, and Genomics, University of Georgia, Athens, GA 30602, U.S.A
| | - Melissa G Mitchum
- Department of Plant Pathology and Institute of Plant Breeding, Genetics, and Genomics, University of Georgia, Athens, GA 30602, U.S.A
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3
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Anedo EO, Beesigamukama D, Mochoge B, Korir NK, Haukeland S, Cheseto X, Subramanian S, Kelemu S, Tanga CM. Evolving dynamics of insect frass fertilizer for sustainable nematode management and potato production. FRONTIERS IN PLANT SCIENCE 2024; 15:1343038. [PMID: 38463573 PMCID: PMC10920244 DOI: 10.3389/fpls.2024.1343038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 02/07/2024] [Indexed: 03/12/2024]
Abstract
Potato production faces major challenges from inadequate soil fertility, and nematode infestation, yet synthetic fertilizers and nematicides are costly and harmful to the environment. This study explored the potential of chitin-fortified black soldier fly-composted organic fertilizer (BSFCOF) as a multipurpose organic fertilizer amendment for enhancing potato yield and suppressing potato cyst nematodes (PCN). The BSFCOF was applied at a rate equivalent to 150 kg N ha-1 and fortified with chitin from black soldier fly pupal exuviae at inclusion rates equivalent to 0.5, 1, 2, 3, 4 and 5% chitin. Data were collected on potato growth characteristics, PCN population densities, and soil chemical properties for two growing cycles. Results showed that chitin fortified BSFCOF significantly improved potato growth parameters, chlorophyll concentration, marketable tuber yield and number of marketable tubers. The marketable tuber yield achieved using chitin-fortified BSFCOF was 70 - 362%, and 69 - 238% higher than the values achieved using unfertilized soil during the first and second growing cycles, respectively. Soil amendment with chitin-fortified BSFCOF significantly reduced the number of cysts per 200 g soil-1, number of eggs and J2 per cyst-1, eggs g-1 soil and reproduction rate by 32 - 87%, 9 - 92%, 31- 98% and 31 - 98%, respectively. The PCN suppression increased with chitin inclusion rates. There were significantly higher values for soil pH, ammonium nitrogen, nitrate nitrogen, available phosphorus, calcium, magnesium, potassium, and cation exchange capacity in soil amended with BSFCOF compared to unamended soil. This study demonstrates that BSFCOF fortified with 5% chitin is an effective soil enhancer with multiple benefits, including improved soil fertility, potato performance, and effective management of potato cyst nematodes.
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Affiliation(s)
- Emmanuel O. Anedo
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya
- Department of Agricultural Science and Technology, Kenyatta University, Nairobi, Kenya
- Crop Research Operations Department, National Root Crops Research Institute, Umudike, Abia State, Nigeria
| | | | - Benson Mochoge
- Department of Agricultural Science and Technology, Kenyatta University, Nairobi, Kenya
| | - Nicholas K. Korir
- Department of Agricultural Science and Technology, Kenyatta University, Nairobi, Kenya
| | - Solveig Haukeland
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya
- Division of Biotechnology and Plant Health, Norwegian Institute for Bioeconomy Research (NIBIO), Ås, Norway
| | - Xavier Cheseto
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya
| | | | - Segenet Kelemu
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya
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Nematicidal Effects of Volatile Organic Compounds from Microorganisms and Plants on Plant-Parasitic Nematodes. Microorganisms 2022; 10:microorganisms10061201. [PMID: 35744719 PMCID: PMC9228967 DOI: 10.3390/microorganisms10061201] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 06/09/2022] [Accepted: 06/10/2022] [Indexed: 12/10/2022] Open
Abstract
Plant-parasitic nematodes (PPNs) are one of the most destructive plant pathogens worldwide, and controlling them is extremely challenging. Volatile organic compounds (VOCs), which naturally exist in plants and microorganisms, play an important role in the biological control of PPNs and are considered potential substances for the development of commercial nematicides. This paper summarizes the VOCs produced by microorganisms and plants as well as their toxic effects on PPNs. VOCs from 26 microbial strains and 51 plants that are active against nematodes from over the last decade were reviewed. Furthermore, the mechanisms of toxicity of some VOCs against PPNs are also illustrated.
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Sanadhya P, Kumar A, Bucki P, Fitoussi N, Carmeli-Weissberg M, Borenstein M, Brown-Miyara S. Tomato Divinyl Ether-Biosynthesis Pathway Is Implicated in Modulating of Root-Knot Nematode Meloidogyne javanica's Parasitic Ability. FRONTIERS IN PLANT SCIENCE 2021; 12:670772. [PMID: 34512679 PMCID: PMC8424051 DOI: 10.3389/fpls.2021.670772] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 07/21/2021] [Indexed: 05/27/2023]
Abstract
The role of the 9-lipoxygenase (9-LOX)-derived oxylipins in plant defense is mainly known in solanaceous plants. In this work, we identify the functional role of the tomato divinyl ether synthase (LeDES) branch, which exclusively converts 9-hydroperoxides to the 9-divinyl ethers (DVEs) colneleic acid (CA) and colnelenic acid (CnA), during infection by the root-knot nematode Meloidogyne javanica. Analysis of LeDES expression in roots indicated a concurrent response to nematode infection, demonstrating a sharp increase in expression during the molting of third/fourth-stage juveniles, 15 days after inoculation. Spatiotemporal expression analysis using an LeDES promoter:GUS tomato line showed high GUS activity associated with the developing gall; however the GUS signal became more constricted as infection progressed to the mature nematode feeding sites, and eventually disappeared. Wounding did not activate the LeDES promoter, but auxins and methyl salicylate triggered LeDES expression, indicating a hormone-mediated function of DVEs. Heterologous expression of LeDES in Arabidopsis thaliana rendered the plants more resistant to nematode infection and resulted in a significant reduction in third/fourth-stage juveniles and adult females as compared to a vector control and the wild type. To further evaluate the nematotoxic activity of the DVEs CA and CnA, recombinant yeast that catalyzes the formation of CA and CnA from 9-hydroperoxides was generated. Transgenic yeast accumulating CnA was tested for its impact on M. javanica juveniles, indicating a decrease in second-stage juvenile motility. Taken together, our results suggest an important role for LeDES as a determinant in the defense response during M. javanica parasitism, and indicate two functional modes: directly via DVE motility inhibition effect and through signal molecule-mediated defense reactions to nematodes that depend on methyl salicylate.
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Affiliation(s)
- Payal Sanadhya
- Department of Entomology, Nematology and Chemistry Units, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel
| | - Anil Kumar
- Department of Entomology, Nematology and Chemistry Units, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel
| | - Patricia Bucki
- Department of Entomology, Nematology and Chemistry Units, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel
| | - Nathalia Fitoussi
- Department of Entomology, Nematology and Chemistry Units, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel
- Department of Plant Pathology and Microbiology, The Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Mira Carmeli-Weissberg
- Metabolomics, Institute of Plant Sciences, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel
| | - Menachem Borenstein
- Department of Plant Pathology and Weed Research, Agricultural Research Organization (ARO), The Volcani Center, Bet Dagan, Israel
| | - Sigal Brown-Miyara
- Department of Entomology, Nematology and Chemistry Units, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel
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Kozlowski DKL, Hassanaly‐Goulamhoussen R, Da Rocha M, Koutsovoulos GD, Bailly‐Bechet M, Danchin EGJ. Movements of transposable elements contribute to the genomic plasticity and species diversification in an asexually reproducing nematode pest. Evol Appl 2021; 14:1844-1866. [PMID: 34295368 PMCID: PMC8288018 DOI: 10.1111/eva.13246] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 04/12/2021] [Accepted: 04/15/2021] [Indexed: 12/14/2022] Open
Abstract
Despite reproducing without sexual recombination, Meloidogyne incognita is an adaptive and versatile phytoparasitic nematode. This species displays a global distribution, can parasitize a large range of plants, and can overcome plant resistance in a few generations. The mechanisms underlying this adaptability remain poorly known. At the whole-genome level, only a few single nucleotide variations have been observed across different geographical isolates with distinct ranges of compatible hosts. Exploring other factors possibly involved in genomic plasticity is thus important. Transposable elements (TEs), by their repetitive nature and mobility, can passively and actively impact the genome dynamics. This is particularly expected in polyploid hybrid genomes such as the one of M. incognita. Here, we have annotated the TE content of M. incognita, analyzed the statistical properties of this TE landscape, and used whole-genome pool-seq data to estimate the mobility of these TEs across twelve geographical isolates, presenting variations in ranges of compatible host plants. DNA transposons are more abundant than retrotransposons, and the high similarity of TE copies to their consensus sequences suggests they have been at least recently active. We have identified loci in the genome where the frequencies of presence of a TE showed substantial variations across the different isolates. Overall, variations in TE frequencies across isolates followed their phylogenetic divergence, suggesting TEs participate in the species diversification. Compared with the M. incognita reference genome, we detected isolate and lineage-specific de novo insertion of some TEs, including within genic regions or in the upstream regulatory regions. We validated by PCR the insertion of some of these TEs inside genic regions, confirming TE movements have possible functional impacts. Overall, we show DNA transposons can drive genomic plasticity in M. incognita and their role in genome evolution of other parthenogenetic animal deserves further investigation.
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Touray M, Cimen H, Gulsen SH, Ulug D, Erdogus D, Shapiro-Ilan D, Hazir S. The impact of chemical nematicides on entomopathogenic nematode survival and infectivity. J Nematol 2021. [DOI: 10.21307/jofnem-2021-049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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8
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Fráguas RM, Costa VA, Terra WC, Aguiar AP, Martins SJ, Campos VP, Oliveira DF. Toxicities of 4,5-Dihydroisoxazoles Against Root-Knot Nematodes and in Silico Studies of Their Modes of Action. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:523-529. [PMID: 31908169 DOI: 10.1021/acs.jafc.9b07839] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The present work sought to contribute to the development of new nematicides. Benzaldehydes were initially converted to nitrile oxides that underwent 1,3-dipolar cycloaddition reactions with methyl acrylate to generate 4,5-dihydroisoxazoles. In in vitro tests, methyl 3-phenyl-4,5-dihydroisoxazole-5-carboxylate (1) and methyl 3-(4-chlorophenyl)-4,5-dihydroisoxazole-5-carboxylate (4) increased the mortality of Meloidogyne exigua and Meloidogyne incognita second-stage juveniles (J2). Compounds 1 and 4 presented necessary concentrations of 398 and 501 μg mL-1, respectively, to kill 50% of M. incognita J2 (LC50 values), while the value for carbofuran (positive control) was 168 μg mL-1. In in vivo tests, compounds 1 and 4 reduced the number of M. incognita galls in tomato roots by 70 and 40%, respectively, and the number of eggs by 89 and 44%. Using an in silico approach, we showed that compounds 1 and 4 were toxic to the nematodes by binding to the allosteric binding sites of the agonist-binding domains of the nematode nicotinic acetylcholine receptors. These results opened up possibilities for further investigations aimed at developing novel commercial nematicides.
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Affiliation(s)
- Rodrigo M Fráguas
- Laboratory of Organic Synthesis, Department of Chemistry , Instituto Militar de Engenharia , Rio de Janeiro CEP 22290-270 , Brazil
| | | | | | - Alcino P Aguiar
- Laboratory of Organic Synthesis, Department of Chemistry , Instituto Militar de Engenharia , Rio de Janeiro CEP 22290-270 , Brazil
| | - Samuel J Martins
- Department of Plant Pathology and Environmental Microbiology , Pennsylvania State University , University Park , State College , Pennsylvania 16802 , United States
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Silva AC, Ruiz-Ferrer V, Martínez-Gómez Á, Barcala M, Fenoll C, Escobar C. All in One High Quality Genomic DNA and Total RNA Extraction From Nematode Induced Galls for High Throughput Sequencing Purposes. FRONTIERS IN PLANT SCIENCE 2019; 10:657. [PMID: 31214210 PMCID: PMC6554733 DOI: 10.3389/fpls.2019.00657] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2019] [Accepted: 05/01/2019] [Indexed: 05/06/2023]
Abstract
Meloidogyne spp. are plant-parasitic nematodes that form a very complex pseudo-organ, called gall, which contains the giant cells (GCs) to nourish them. During the last decade, several groups have been studying the molecular processes accompanying the formation of these structures, combining both transcriptomics and cellular biology. Among others, it was confirmed that a generalized gene repression is a hallmark of early developing GCs formed by Meloidogyne javanica in Arabidopsis and tomato. One of the main mechanisms behind this gene repression involve small RNAs (sRNAs) directed gene silencing. This is supported not only by the described action of several microRNAs differentially expressed in galls, but by the differential abundance of 24-nucleotide sRNAs in early developing Arabidopsis galls, particularly those rasiRNAs which are mostly involved in RNA-directed DNA methylation. Their accumulation strongly correlates to the repression of several retrotransposons at pericentromeric regions of Arabidopsis chromosomes in early galls. However, the contribution of this global gene repression to GCs/galls formation and maintenance is still not fully understood. Further detailed studies, as the correlation between gene expression profiles and the methylation state of the chromatin in galls are essential to raise testable working hypotheses. A high quality of isolated DNA and RNA is a requirement to obtain non-biased and comprehensive results. Frequently, the isolation of DNA and RNA is performed from different samples of the same type of biological material. However, subtle differences on epigenetic processes are frequent even among independent biological replicates of the same tissue and may not correlate to those changes on the mRNA population obtained from different biological replicates. Herein, we describe a method that allows the simultaneous extraction and purification of genomic DNA and total RNA from the same biological sample adapted to our biological system. The quality of both nucleic acids from Arabidopsis galls formed by M. javanica was high and adequate to construct RNA and DNA libraries for high throughput sequencing used for transcriptomic and epigenetic studies, such as the analysis of the methylation state of the genomic DNA in galls (MethylC-seq) and RNA sequencing (RNAseq). The protocol presents guidance on the described procedure, key notes and troubleshooting.
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Affiliation(s)
- Ana Cláudia Silva
- Facultad de Ciencias Ambientales y Bioquímica, Universidad de Castilla-La Mancha, Toledo, Spain
| | - Virginia Ruiz-Ferrer
- Facultad de Ciencias Ambientales y Bioquímica, Universidad de Castilla-La Mancha, Toledo, Spain
| | - Ángela Martínez-Gómez
- Facultad de Ciencias Ambientales y Bioquímica, Universidad de Castilla-La Mancha, Toledo, Spain
| | - Marta Barcala
- Facultad de Ciencias Ambientales y Bioquímica, Universidad de Castilla-La Mancha, Toledo, Spain
| | - Carmen Fenoll
- Facultad de Ciencias Ambientales y Bioquímica, Universidad de Castilla-La Mancha, Toledo, Spain
| | - Carolina Escobar
- Facultad de Ciencias Ambientales y Bioquímica, Universidad de Castilla-La Mancha, Toledo, Spain
- International Research Organization for Advanced Science and Technology (IROAST), Kumamoto University, Kumamoto, Japan
- *Correspondence: Carolina Escobar,
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Kang BR, Anderson AJ, Kim YC. Hydrogen Cyanide Produced by Pseudomonas chlororaphis O6 Exhibits Nematicidal Activity against Meloidogyne hapla. THE PLANT PATHOLOGY JOURNAL 2018; 34:35-43. [PMID: 29422786 PMCID: PMC5796748 DOI: 10.5423/ppj.oa.06.2017.0115] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Revised: 11/16/2017] [Accepted: 11/23/2017] [Indexed: 05/09/2023]
Abstract
Root-knot nematodes (Meloidogyne spp.) are parasites that attack many field crops and orchard trees, and affect both the quantity and quality of the products. A root-colonizing bacterium, Pseudomonas chlororaphis O6, possesses beneficial traits including strong nematicidal activity. To determine the molecular mechanisms involved in the nematicidal activity of P. chlororaphis O6, we constructed two mutants; one lacking hydrogen cyanide production, and a second lacking an insecticidal toxin, FitD. Root drenching with wild-type P. chlororaphis O6 cells caused juvenile mortality in vitro and in planta. Efficacy was not altered in the fitD mutant compared to the wild-type but was reduced in both bioassays for the mutant lacking hydrogen cyanide production. The reduced number of galls on tomato plants caused by the wild-type strain was comparable to that of a standard chemical nematicide. These findings suggest that hydrogen cyanide-producing root colonizers, such as P. chlororaphis O6, could be formulated as "green" nematicides that are compatible with many crops and offer agricultural sustainability.
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Affiliation(s)
- Beom Ryong Kang
- Institute of Environmentally-Friendly Agriculture, Chonnam National University, Gwangju 61186,
Korea
| | - Anne J. Anderson
- Department of Biology, Utah State University, Logan, UT 84322-5305,
USA
| | - Young Cheol Kim
- Institute of Environmentally-Friendly Agriculture, Chonnam National University, Gwangju 61186,
Korea
- Corresponding author. Phone) +82-62-530-2071, FAX) +82-62-530-0208, E-mail)
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Abstract
Plant-parasitic nematodes cause considerable damage to global agriculture. The ability to
parasitize plants is a derived character that appears to have independently emerged
several times in the phylum Nematoda. Morphological convergence to feeding style has been
observed, but whether this is emergent from molecular convergence is less obvious. To
address this, we assess whether genomic signatures can be associated with plant parasitism
by nematodes. In this review, we report genomic features and characteristics that appear
to be common in plant-parasitic nematodes while absent or rare in animal parasites,
predators or free-living species. Candidate horizontal acquisitions of parasitism genes
have systematically been found in all plant-parasitic species investigated at the sequence
level. Presence of peptides that mimic plant hormones also appears to be a trait of
plant-parasitic species. Annotations of the few genomes of plant-parasitic nematodes
available to date have revealed a set of apparently species-specific genes on every
occasion. Effector genes, important for parasitism are frequently found among those
species-specific genes, indicating poor overlap. Overall, nematodes appear to have
developed convergent genomic solutions to adapt to plant parasitism.
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Rocha TL, Soll CB, Boughton BA, Silva TS, Oldach K, Firmino AA, Callahan DL, Sheedy J, Silveira ER, Carneiro RM, Silva LP, Polez VL, Pelegrini PB, Bacic A, Grossi-de-Sa MF, Roessner U. Prospection and identification of nematotoxic compounds from Canavalia ensiformis seeds effective in the control of the root knot nematode Meloidogyne incognita. ACTA ACUST UNITED AC 2017. [DOI: 10.1016/j.biori.2017.10.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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13
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Rocha RO, Morais JKS, Oliveira JTA, Oliveira HD, Sousa DOB, Souza CEA, Moreno FB, Monteiro-Moreira ACO, de Souza Júnior JDA, de Sá MFG, Vasconcelos IM. Proteome of Soybean Seed Exudates Contains Plant Defense-Related Proteins Active against the Root-Knot Nematode Meloidogyne incognita. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2015; 63:5335-43. [PMID: 26034922 DOI: 10.1021/acs.jafc.5b01109] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Several studies have described the effects of seed exudates against microorganisms, but only few of them have investigated the proteins that have defensive activity particularly against nematode parasites. This study focused on the proteins released in the exudates of soybean seeds and evaluated their nematicidal properties against Meloidogyne incognita. A proteomic approach indicated the existence of 63 exuded proteins, including β-1,3-glucanase, chitinase, lectin, trypsin inhibitor, and lipoxygenase, all of which are related to plant defense. The presence of some of these proteins was confirmed by their in vitro activity. The soybean exudates were able to reduce the hatching of nematode eggs and to cause 100% mortality of second-stage juveniles (J2). The pretreatment of J2 with these exudates resulted in a 90% reduction of the gall number in tobacco plants. These findings suggest that the exuded proteins are directly involved in plant defense against soil pathogens, including nematodes, during seed germination.
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Affiliation(s)
- Raquel O Rocha
- †Department of Biochemistry and Molecular Biology, Federal University of Ceará, Campus do Pici, 60440-900 Fortaleza, Ceará, Brazil
| | - Janne K S Morais
- †Department of Biochemistry and Molecular Biology, Federal University of Ceará, Campus do Pici, 60440-900 Fortaleza, Ceará, Brazil
| | - Jose T A Oliveira
- †Department of Biochemistry and Molecular Biology, Federal University of Ceará, Campus do Pici, 60440-900 Fortaleza, Ceará, Brazil
| | - Hermogenes D Oliveira
- †Department of Biochemistry and Molecular Biology, Federal University of Ceará, Campus do Pici, 60440-900 Fortaleza, Ceará, Brazil
| | - Daniele O B Sousa
- †Department of Biochemistry and Molecular Biology, Federal University of Ceará, Campus do Pici, 60440-900 Fortaleza, Ceará, Brazil
| | | | - Frederico B Moreno
- §School of Pharmacy, University of Fortaleza, 60811-905 Fortaleza, Ceará, Brazil
| | | | | | - Maria F Grossi de Sá
- ∥Plant-Pest Interaction Laboratory, Embrapa Genetic Resources and Biotechnology, 70770-900 Brasília, Distrito Federal, Brazil
| | - Ilka M Vasconcelos
- †Department of Biochemistry and Molecular Biology, Federal University of Ceará, Campus do Pici, 60440-900 Fortaleza, Ceará, Brazil
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Vieira P, Wantoch S, Lilley CJ, Chitwood DJ, Atkinson HJ, Kamo K. Expression of a cystatin transgene can confer resistance to root lesion nematodes in Lilium longiflorum cv. 'Nellie White'. Transgenic Res 2015; 24:421-32. [PMID: 25398618 DOI: 10.1007/s11248-014-9848-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Accepted: 11/04/2014] [Indexed: 10/24/2022]
Abstract
Lilium longiflorum cv. 'Nellie White' assumes a great economic importance as cut flowers, being one of the most valuable species (annual pot plants value above $20,000,000) in terms of wholesales in the US. The root lesion nematode Pratylenchus penetrans (RLN) constitutes one of the main pests for lily producers due to the significant root damage it causes. Our efforts have focused on the generation of soybean hairy roots (as a transient test model) and stable transgenic lilies overexpressing a modified rice cystatin (Oc-IΔD86) transgene and challenged with root lesion nematodes. Lily transformation was achieved by gene gun co-bombardment using both a pBluescript-based vector containing the cystatin gene and pDM307 that contains a bar gene for phosphinothricin selection. Both soybean hairy roots and lilies overexpressing the OcIΔD86 transgene exhibited enhanced resistance to RLN infection by means of nematode reduction up to 75 ± 5% on the total number of nematodes. In addition, lily plants overexpressing OcIΔD86 displayed an increase of plant mass and better growth performance in comparison to wild-type plants, thereby demonstrating an alternative strategy for increasing the yield and reducing nematode damage to this important floral crop.
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Affiliation(s)
- Paulo Vieira
- Floral and Nursery Plants Research Unit, U.S. National Arboretum, U.S. Department of Agriculture (USDA) ARS, BARC West, 10300 Baltimore Avenue, Building 010A Room 126, Beltsville, MD, 20705-2350, USA,
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Jang JY, Dang QL, Choi YH, Choi GJ, Jang KS, Cha B, Luu NH, Kim JC. Nematicidal activities of 4-quinolone alkaloids isolated from the aerial part of Triumfetta grandidens against Meloidogyne incognita. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2015; 63:68-74. [PMID: 25494674 DOI: 10.1021/jf504572h] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The methanol extract of the aerial part of Triumfetta grandidens (Tiliaceae) was highly active against Meloidogyne incognita, with second-stage juveniles (J2s) mortality of 100% at 500 μg/mL at 48 h post-exposure. Two 4-quinolone alkaloids, waltherione E (1), a new alkaloid, and waltherione A (2), were isolated and identified as nematicidal compounds through bioassay-guided fractionation and instrumental analysis. The nematicidal activities of the isolated compounds against M. incognita were evaluated on the basis of mortality and effect on egg hatching. Compounds 1 and 2 exhibited high mortalities against J2s of M. incognita, with EC50 values of 0.09 and 0.27 μg/mL at 48 h, respectively. Compounds 1 and 2 also exhibited a considerable inhibitory effect on egg hatching, which inhibited 91.9 and 87.4% of egg hatching, respectively, after 7 days of exposure at a concentration of 1.25 μg/mL. The biological activities of the two 4-quinolone alkaloids were comparable to those of abamectin. In addition, pot experiments using the crude extract of the aerial part of T. grandidens showed that it completely suppressed the formation of gall on roots of plants at a concentration of 1000 μg/mL. These results suggest that T. grandidens and its bioactive 4-quinolone alkaloids can be used as a potent botanical nematicide in organic agriculture.
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Abebe E, Mekete T, Seid A, Meressa BH, Wondafrash M, Addis T, Getaneh G, Abate BA. Research on plant-parasitic and entomopathogenic nematodes in Ethiopia: a review of current state and future direction. NEMATOLOGY 2015. [DOI: 10.1163/15685411-00002919] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Food self-sufficiency is Ethiopia’s national priority goal. Given that pest management seriously impacts agriculture, research on crop diseases is of paramount significance to the national goal. Here we provide a comprehensive account of research on plant-parasitic and entomopathogenic nematodes in Ethiopia. We show that the limited information available indicates that plant-parasitic nematodes impact crop production. There exists a serious gap in knowledge with regard to the effects of plant-parasitic nematodes on almost all major crops. This gap includes surveys with appropriate levels of identification, distribution, and yield loss and damage threshold studies on target crops. The current state of knowledge hinders the nation’s ability to design and implement appropriate control strategies for plant-parasitic nematodes. We propose a strategic assessment of plant-parasitic nematodes of all major crops, the need for systematic manpower training and continued search for entomopathogenic nematodes in the major agro-ecological zones of the nation and further research on those entomopathogenic nematodes already identified.
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Affiliation(s)
- Eyualem Abebe
- Elizabeth City State University, Elizabeth City, NC 27909, USA
| | - Tesfamariam Mekete
- Department of Entomology and Nematology, University of Florida, Gainesville, FL 32611, USA
| | - Awol Seid
- Haramaya University, College of Agriculture and Environmental Sciences, School of Plant Sciences, P.O. Box 138, Dire Dawa, Ethiopia
| | - Beira H. Meressa
- Julius Kühn-Institut, Federal Research Center for Cultivated Plants, Institute for Epidemiology and Pathogen Diagnostics, Toppheideweg 88, 48161 Münster, Germany
| | - Mesfin Wondafrash
- Haramaya University, College of Agriculture and Environmental Sciences, School of Plant Sciences, P.O. Box 138, Dire Dawa, Ethiopia
- Department of Zoology and Entomology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria 0028, South Africa
| | - Temesgen Addis
- Faculty of Agricultural and Nutritional Sciences, Christian-Albrechts-University Kiel, Hermann-Rodewald-Str. 4, 24118 Kiel, Germany
| | - Gezahegn Getaneh
- College of Veterinary Medicine and Agriculture, Salale Campus, Addis Ababa University P.O. Box 245, Fitche, Ethiopia
| | - Birhan A. Abate
- Department of Zoology and Entomology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria 0028, South Africa
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Apoplastic venom allergen-like proteins of cyst nematodes modulate the activation of basal plant innate immunity by cell surface receptors. PLoS Pathog 2014; 10:e1004569. [PMID: 25500833 PMCID: PMC4263768 DOI: 10.1371/journal.ppat.1004569] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Accepted: 11/11/2014] [Indexed: 11/26/2022] Open
Abstract
Despite causing considerable damage to host tissue during the onset of parasitism, nematodes establish remarkably persistent infections in both animals and plants. It is thought that an elaborate repertoire of effector proteins in nematode secretions suppresses damage-triggered immune responses of the host. However, the nature and mode of action of most immunomodulatory compounds in nematode secretions are not well understood. Here, we show that venom allergen-like proteins of plant-parasitic nematodes selectively suppress host immunity mediated by surface-localized immune receptors. Venom allergen-like proteins are uniquely conserved in secretions of all animal- and plant-parasitic nematodes studied to date, but their role during the onset of parasitism has thus far remained elusive. Knocking-down the expression of the venom allergen-like protein Gr-VAP1 severely hampered the infectivity of the potato cyst nematode Globodera rostochiensis. By contrast, heterologous expression of Gr-VAP1 and two other venom allergen-like proteins from the beet cyst nematode Heterodera schachtii in plants resulted in the loss of basal immunity to multiple unrelated pathogens. The modulation of basal immunity by ectopic venom allergen-like proteins in Arabidopsis thaliana involved extracellular protease-based host defenses and non-photochemical quenching in chloroplasts. Non-photochemical quenching regulates the initiation of the defense-related programmed cell death, the onset of which was commonly suppressed by venom allergen-like proteins from G. rostochiensis, H. schachtii, and the root-knot nematode Meloidogyne incognita. Surprisingly, these venom allergen-like proteins only affected the programmed cell death mediated by surface-localized immune receptors. Furthermore, the delivery of venom allergen-like proteins into host tissue coincides with the enzymatic breakdown of plant cell walls by migratory nematodes. We, therefore, conclude that parasitic nematodes most likely utilize venom allergen-like proteins to suppress the activation of defenses by immunogenic breakdown products in damaged host tissue. Plant-parasitic nematodes have a major impact on global food security, as they reduce the annual yield of food crops by approximately 10 percent. For decades, the application of non-selective toxic chemicals to infested soils controlled outbreaks of plant-parasitic nematodes. The recent bans on most of these chemicals has redirected attention towards a wider use of basal, broad-spectrum immunity to nematodes in crop cultivars. However, it is currently not known if this most ancient layer of immunity affects host invasion by plant-parasitic nematodes at all. Basal immunity in plants relies on the detection of molecular patterns uniquely associated with infections in the apoplast by surface-localized receptors. Here, we demonstrate that venom allergen-like proteins in secretions of soil-borne cyst nematodes suppress immune responses mediated by surface-localized pattern recognition receptors. Migratory stages of cyst nematodes most likely deliver venom allergen-like proteins together with a range of plant cell wall-degrading enzymes into the apoplast of host cells. We therefore conclude that these nematodes most likely secrete venom allergen-like proteins to modulate host responses triggered by the release of immunogenic fragments of damaged plant cell walls.
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Kyndt T, Fernandez D, Gheysen G. Plant-parasitic nematode infections in rice: molecular and cellular insights. ANNUAL REVIEW OF PHYTOPATHOLOGY 2014; 52:135-53. [PMID: 24906129 DOI: 10.1146/annurev-phyto-102313-050111] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Being one of the major staple foods in the world, and an interesting model monocot plant, rice (Oryza sativa L.) has recently received attention from molecular nematologists studying the cellular and molecular aspects of the interaction between this crop and plant-parasitic nematodes. In this review, we highlight recent advances in this field, with a focus on the best-studied root-knot nematodes. Histological studies have revealed the cellular changes inside root-knot nematode-induced feeding sites, both in the compatible interaction with Oryza sativa and the incompatible interaction with the related species Oryza glaberrima. After comparing the published data from transcriptome analyses, mutant studies, and exogenous hormone applications, we provide a comprehensive model showing the role and interaction of plant hormone pathways in defense of this monocot crop against root nematodes, where jasmonate seems to play a key role. Finally, recent evidence indicates that effectors secreted from rice-infecting nematodes can suppress plant defense.
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Affiliation(s)
- Tina Kyndt
- Department of Molecular Biotechnology, Ghent University, 9000 Ghent, Belgium; ,
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Masler EP. Targeting internal processes of plant-parasitic nematodes in the pursuit of novel agents for their control. NEMATOLOGY 2014. [DOI: 10.1163/15685411-00002829] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The success of plant-parasitic nematodes as competitors with humans for crops is evidenced by the parasites’ significant and continuous economic drain on global agriculture. Scientific efforts dedicated to the control of plant-parasitic nematodes employ strategies from the environmental to molecular levels. Understanding the interaction of the nematode with its environment, and the molecules involved, offers great promise for novel control agent development. Perhaps more significantly, such knowledge facilitates the generation of ever more detailed and sophisticated information on nematode biology and new molecular targets. Among the most economically important groups of plant-parasitic nematodes are those comprising the cyst-forming species and the root-knot nematodes. Presented here is a brief overview of research into the biology of these parasites relative to their life cycles. Recent advances in elucidating the molecular biology and biochemistry of nematode-plant interactions during the internal parasitic stages of the life cycle have been driven by advances in genomics and transcriptomics. The remarkable discoveries regarding parasitism, and the application of genetic resources in these findings, provide a template for advanced investigation of external, survival stages biology. While survival biology research lags somewhat behind that of parasitism with regard to the molecular genetics of signalling and response, its extensive catalogue promises explosive rates of discovery as progress in genomics and transcriptomics allows a molecular genetic examination of embryogenesis, dormancy and hatching. Our group is interested in behaviour, development and hatching of cyst and root-knot nematodes, and the effects of the environment on the mechanisms of these activities. Phytochemical and temperature effects are discussed, and evidence is presented that the cyst may provide useful molecules for exploring nematode physiology.
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Affiliation(s)
- Edward P. Masler
- USDA-ARS Nematology Laboratory, 10300 Baltimore Avenue, Beltsville, MD 20705, USA
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Identification of novel target genes for safer and more specific control of root-knot nematodes from a pan-genome mining. PLoS Pathog 2013; 9:e1003745. [PMID: 24204279 PMCID: PMC3814813 DOI: 10.1371/journal.ppat.1003745] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Accepted: 09/19/2013] [Indexed: 11/27/2022] Open
Abstract
Root-knot nematodes are globally the most aggressive and damaging plant-parasitic nematodes. Chemical nematicides have so far constituted the most efficient control measures against these agricultural pests. Because of their toxicity for the environment and danger for human health, these nematicides have now been banned from use. Consequently, new and more specific control means, safe for the environment and human health, are urgently needed to avoid worldwide proliferation of these devastating plant-parasites. Mining the genomes of root-knot nematodes through an evolutionary and comparative genomics approach, we identified and analyzed 15,952 nematode genes conserved in genomes of plant-damaging species but absent from non target genomes of chordates, plants, annelids, insect pollinators and mollusks. Functional annotation of the corresponding proteins revealed a relative abundance of putative transcription factors in this parasite-specific set compared to whole proteomes of root-knot nematodes. This may point to important and specific regulators of genes involved in parasitism. Because these nematodes are known to secrete effector proteins in planta, essential for parasitism, we searched and identified 993 such effector-like proteins absent from non-target species. Aiming at identifying novel targets for the development of future control methods, we biologically tested the effect of inactivation of the corresponding genes through RNA interference. A total of 15 novel effector-like proteins and one putative transcription factor compatible with the design of siRNAs were present as non-redundant genes and had transcriptional support in the model root-knot nematode Meloidogyne incognita. Infestation assays with siRNA-treated M. incognita on tomato plants showed significant and reproducible reduction of the infestation for 12 of the 16 tested genes compared to control nematodes. These 12 novel genes, showing efficient reduction of parasitism when silenced, constitute promising targets for the development of more specific and safer control means. Plant-parasitic nematodes are annually responsible for more than $100 billion crop yield loss worldwide and those considered as causing most of the damages are root-knot nematodes. These nematodes used to be controlled by chemicals that are now banned from use because of their poor specificity and high toxicity for the environment and human health. In the absence of sustainable alternative solutions, new control means, more specifically targeted against these nematodes and safe for the environment are needed. We searched in root-knot nematode genomes, genes conserved in various plant-damaging species while otherwise absent from the genomes of non target species such as those of chordates, plants, annelids, insect pollinators and mollusks. These genes are probably important for plant parasitism and their absence from non-target species make them interesting candidates for the development of more specific and safer control means. Further bioinformatics pruning of this set of genes yielded 16 novel candidates that could be biologically tested. Using RNA interference, we knocked down each of these 16 genes in a root-knot nematode and tested the effect on plant parasitism efficiency. Out of the 16 tested genes, 12 showed a significant and reproducible diminution of infestation when silenced and are thus particularly promising.
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Atkinson LE, Stevenson M, McCoy CJ, Marks NJ, Fleming C, Zamanian M, Day TA, Kimber MJ, Maule AG, Mousley A. flp-32 Ligand/receptor silencing phenocopy faster plant pathogenic nematodes. PLoS Pathog 2013; 9:e1003169. [PMID: 23468621 PMCID: PMC3585147 DOI: 10.1371/journal.ppat.1003169] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Accepted: 12/18/2012] [Indexed: 11/27/2022] Open
Abstract
Restrictions on nematicide usage underscore the need for novel control strategies for plant pathogenic nematodes such as Globodera pallida (potato cyst nematode) that impose a significant economic burden on plant cultivation activities. The nematode neuropeptide signalling system is an attractive resource for novel control targets as it plays a critical role in sensory and motor functions. The FMRFamide-like peptides (FLPs) form the largest and most diverse family of neuropeptides in invertebrates, and are structurally conserved across nematode species, highlighting the utility of the FLPergic system as a broad-spectrum control target. flp-32 is expressed widely across nematode species. This study investigates the role of flp-32 in G. pallida and shows that: (i) Gp-flp-32 encodes the peptide AMRNALVRFamide; (ii) Gp-flp-32 is expressed in the brain and ventral nerve cord of G. pallida; (iii) migration rate increases in Gp-flp-32-silenced worms; (iv) the ability of G. pallida to infect potato plant root systems is enhanced in Gp-flp-32-silenced worms; (v) a novel putative Gp-flp-32 receptor (Gp-flp-32R) is expressed in G. pallida; and, (vi) Gp-flp-32R-silenced worms also display an increase in migration rate. This work demonstrates that Gp-flp-32 plays an intrinsic role in the modulation of locomotory behaviour in G. pallida and putatively interacts with at least one novel G-protein coupled receptor (Gp-flp-32R). This is the first functional characterisation of a parasitic nematode FLP-GPCR. Plant pathogenic nematodes compromise plant health and productivity globally and are an increasing problem due to the lack of efficient control measures. The nematode nervous system depends heavily on small proteins (neuropeptides) for communication between nerve cells and other nerve cells or other cell types. The disruption of neuropeptide signalling would dysregulate normal behaviour, offering an attractive approach to parasite control. One major group of nematode neuropeptides are the FMRFamide-like peptides (FLPs) that alter nematode behaviour by acting on receptors designated G-protein coupled receptors (GPCRs). GPCRs are attractive targets based on their potential ‘druggability;″ indeed they are targets for many human medicines. This study investigates the functional biology of flp-32, a commonly expressed nematode flp, and a novel FLP-32 receptor in a plant pathogenic nematode of major agricultural importance, Globodera pallida. We show that FLP-32 occurs widely in these parasites and interacts with a novel FLP-32 receptor to modulate their behaviour, affecting their movement and the rate at which they infect host plants. These data indicate that chemicals that activate the FLP-32 receptor in these parasites could effectively slow the worms, potentially making them less successful parasites. The conservation of the FLP-32 ligand and receptor across many different nematode parasites adds to its appeal as a potential target for broad-spectrum parasite control.
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Affiliation(s)
- Louise E. Atkinson
- Molecular Biosciences-Parasitology, Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Belfast, United Kingdom
| | - Michael Stevenson
- Molecular Biosciences-Parasitology, Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Belfast, United Kingdom
| | - Ciaran J. McCoy
- Molecular Biosciences-Parasitology, Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Belfast, United Kingdom
| | - Nikki J. Marks
- Molecular Biosciences-Parasitology, Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Belfast, United Kingdom
| | - Colin Fleming
- Agri-Food and Biosciences Institute, Belfast, United Kingdom
| | - Mostafa Zamanian
- Institute of Parasitology, McGill University, Ste. Anne de Bellevue, Quebec, Canada
| | - Tim A. Day
- Department of Biomedical Sciences, Iowa State University, Ames, Iowa, United States of America
| | - Michael J. Kimber
- Department of Biomedical Sciences, Iowa State University, Ames, Iowa, United States of America
| | - Aaron G. Maule
- Molecular Biosciences-Parasitology, Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Belfast, United Kingdom
| | - Angela Mousley
- Molecular Biosciences-Parasitology, Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Belfast, United Kingdom
- * E-mail:
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Xu DL, Long H, Liang JJ, Zhang J, Chen X, Li JL, Pan ZF, Deng GB, Yu MQ. De novo assembly and characterization of the root transcriptome of Aegilops variabilis during an interaction with the cereal cyst nematode. BMC Genomics 2012; 13:133. [PMID: 22494814 PMCID: PMC3439707 DOI: 10.1186/1471-2164-13-133] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2011] [Accepted: 04/11/2012] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Aegilops variabilis No.1 is highly resistant to cereal cyst nematode (CCN). However, a lack of genomic information has restricted studies on CCN resistance genes in Ae. variabilis and has limited genetic applications in wheat breeding. RESULTS Using RNA-Seq technology, we generated a root transcriptome at a sequencing depth of 4.69 gigabases of Ae. variabilis No. 1 from a pooled RNA sample. The sample contained equal amounts of RNA extracted from CCN-infected and untreated control plants at three time-points. Using the Trinity method, nearly 52,081,238 high-quality trimmed reads were assembled into a non-redundant set of 118,064 unigenes with an average length of 500 bp and an N50 of 599 bp. The total assembly was 59.09 Mb of unique transcriptome sequences with average read-depth coverage of 33.25×. In BLAST searches of our database against public databases, 66.46% (78,467) of the unigenes were annotated with gene descriptions, conserved protein domains, or gene ontology terms. Functional categorization further revealed 7,408 individual unigenes and three pathways related to plant stress resistance. CONCLUSIONS We conducted high-resolution transcriptome profiling related to root development and the response to CCN infection in Ae. variabilis No.1. This research facilitates further studies on gene discovery and on the molecular mechanisms related to CCN resistance.
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Affiliation(s)
- De-Lin Xu
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan, China
- Graduate University of the Chinese Academy of Sciences, Beijing, China
| | - Hai Long
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan, China
| | - Jun-Jun Liang
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan, China
- Graduate University of the Chinese Academy of Sciences, Beijing, China
| | - Jie Zhang
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan, China
- Graduate University of the Chinese Academy of Sciences, Beijing, China
| | - Xin Chen
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan, China
- Graduate University of the Chinese Academy of Sciences, Beijing, China
| | - Jing-Liang Li
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan, China
- Graduate University of the Chinese Academy of Sciences, Beijing, China
| | - Zhi-Fen Pan
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan, China
| | - Guang-Bing Deng
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan, China
| | - Mao-Qun Yu
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan, China
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Microbial and fungal protease inhibitors--current and potential applications. Appl Microbiol Biotechnol 2012; 93:1351-75. [PMID: 22218770 PMCID: PMC7080157 DOI: 10.1007/s00253-011-3834-x] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2011] [Revised: 12/07/2011] [Accepted: 12/09/2011] [Indexed: 01/18/2023]
Abstract
Proteolytic enzymes play essential metabolic and regulatory functions in many biological processes and also offer a wide range of biotechnological applications. Because of their essential roles, their proteolytic activity needs to be tightly regulated. Therefore, small molecules and proteins that inhibit proteases can be versatile tools in the fields of medicine, agriculture and biotechnology. In medicine, protease inhibitors can be used as diagnostic or therapeutic agents for viral, bacterial, fungal and parasitic diseases as well as for treating cancer and immunological, neurodegenerative and cardiovascular diseases. They can be involved in crop protection against plant pathogens and herbivorous pests as well as against abiotic stress such as drought. Furthermore, protease inhibitors are indispensable in protein purification procedures to prevent undesired proteolysis during heterologous expression or protein extraction. They are also valuable tools for simple and effective purification of proteases, using affinity chromatography. Because there are such a large number and diversity of proteases in prokaryotes, yeasts, filamentous fungi and mushrooms, we can expect them to be a rich source of protease inhibitors as well.
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