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Cardoso JMS, Manadas B, Abrantes I, Robertson L, Arcos SC, Troya MT, Navas A, Fonseca L. Pine wilt disease: what do we know from proteomics? BMC PLANT BIOLOGY 2024; 24:98. [PMID: 38331735 PMCID: PMC10854151 DOI: 10.1186/s12870-024-04771-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Accepted: 01/26/2024] [Indexed: 02/10/2024]
Abstract
Pine wilt disease (PWD) is a devastating forest disease caused by the pinewood nematode (PWN), Bursaphelenchus xylophilus, a migratory endoparasite that infects several coniferous species. During the last 20 years, advances have been made for understanding the molecular bases of PWN-host trees interactions. Major advances emerged from transcriptomic and genomic studies, which revealed some unique features related to PWN pathogenicity and constituted fundamental data that allowed the development of postgenomic studies. Here we review the proteomic approaches that were applied to study PWD and integrated the current knowledge on the molecular basis of the PWN pathogenicity. Proteomics has been useful for understanding cellular activities and protein functions involved in PWN-host trees interactions, shedding light into the mechanisms associated with PWN pathogenicity and being promising tools to better clarify host trees PWN resistance/susceptibility.
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Affiliation(s)
- Joana M S Cardoso
- Centre for Functional Ecology, Associate Laboratory TERRA, Department of Life Sciences, University of Coimbra, Calçada Martins de Freitas, Coimbra, 3000-456, Portugal.
| | - Bruno Manadas
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Rua Larga, Polo I, Coimbra, 3004-504, Portugal
- CIBB - Centre for Innovative Biomedicine and Biotechnology, University of Coimbra, Rua Larga - Faculdade de Medicina, 1ºandar - POLO I, Coimbra, 3004-504, Portugal
| | - Isabel Abrantes
- Centre for Functional Ecology, Associate Laboratory TERRA, Department of Life Sciences, University of Coimbra, Calçada Martins de Freitas, Coimbra, 3000-456, Portugal
| | - Lee Robertson
- Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, CSIC. Instituto de Ciencias Forestales (ICIFOR), Ctra. de La Coruña Km 7.5, Madrid, 28040, Spain
| | - Susana C Arcos
- Museo Nacional de Ciencias Naturales, CSIC. Dpto Biodiversidad y Biología Evolutiva, C/ José Gutiérrez Abascal 2, Madrid, 28006, Spain
| | - Maria Teresa Troya
- Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, CSIC. Instituto de Ciencias Forestales (ICIFOR), Ctra. de La Coruña Km 7.5, Madrid, 28040, Spain
| | - Alfonso Navas
- Museo Nacional de Ciencias Naturales, CSIC. Dpto Biodiversidad y Biología Evolutiva, C/ José Gutiérrez Abascal 2, Madrid, 28006, Spain
| | - Luís Fonseca
- Centre for Functional Ecology, Associate Laboratory TERRA, Department of Life Sciences, University of Coimbra, Calçada Martins de Freitas, Coimbra, 3000-456, Portugal
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Chang Q, Yang Y, Hong B, Zhao Y, Zhao M, Han S, Zhang F, Peng H, Peng D, Li Y. A variant of the venom allergen-like protein, DdVAP2, is required for the migratory endoparasitic plant nematode Ditylenchus destructor parasitism of plants. FRONTIERS IN PLANT SCIENCE 2023; 14:1322902. [PMID: 38152146 PMCID: PMC10751354 DOI: 10.3389/fpls.2023.1322902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 11/28/2023] [Indexed: 12/29/2023]
Abstract
The potato rot nematode, Ditylenchus destructor, poses a serious threat to numerous root and tuber crops, yet the functional characterization of effectors from this migratory endoparasitic plant nematode remains limited. Despite inhabiting distinct habitats, sedentary and migratory plant parasitic nematodes share the structurally conserved effectors, such as venom allergen-like proteins (VAPs). In this study, a variant of DdVAP2 was cloned from D. destructor. The transcription profile analysis revealed that DdVAP2 was higher expressed in D. destructor feeding on either potato or sweet potato compared to on fungus via qRT-PCR. And DdVAP2 was highly expressed at all life stages feeding on sweet potato, except for eggs. DdVAP2 was confirmed to be specifically expressed in the subventral esophageal glands of D. destructor through in situ hybridization assays. Combined with functional validation of the signal peptide of DdVAP2, it suggested that DdVAP2 could be secreted from nematode into host. Heterologous expression of DdVAP2 in Nicotiana benthamiana revealed that the protein localized in both cytosol and nuclei of plant cells. Knocking down DdVAP2 by RNAi in D. destructor resulted in infection and reproduction defects on plants. All the results suggest that DdVAP2 plays a crucial role in the interaction between D. destructor and plants by facilitating the nematode infection.
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Affiliation(s)
- Qing Chang
- Shaanxi Key Laboratory of Plant Nematology, Bio-Agriculture Institute of Shaanxi, Xi’an, China
| | - Yiwei Yang
- Shaanxi Key Laboratory of Plant Nematology, Bio-Agriculture Institute of Shaanxi, Xi’an, China
| | - Bo Hong
- Shaanxi Key Laboratory of Plant Nematology, Bio-Agriculture Institute of Shaanxi, Xi’an, China
| | - Yanqun Zhao
- Yulin Agricultural Technology Service Center, Yulin, China
| | - Mengxin Zhao
- Shaanxi Key Laboratory of Plant Nematology, Bio-Agriculture Institute of Shaanxi, Xi’an, China
| | - Shanshan Han
- Shaanxi Key Laboratory of Plant Nematology, Bio-Agriculture Institute of Shaanxi, Xi’an, China
| | - Feng Zhang
- Shaanxi Key Laboratory of Plant Nematology, Bio-Agriculture Institute of Shaanxi, Xi’an, China
| | - Huan Peng
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Deliang Peng
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yingmei Li
- Shaanxi Key Laboratory of Plant Nematology, Bio-Agriculture Institute of Shaanxi, Xi’an, China
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GAO J, PAN T, CHEN X, Wei Q, Xu L. Proteomic analysis of Masson pine with high resistance to pine wood nematodes. PLoS One 2022; 17:e0273010. [PMID: 35960732 PMCID: PMC9374249 DOI: 10.1371/journal.pone.0273010] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Accepted: 07/29/2022] [Indexed: 11/25/2022] Open
Abstract
Pine wilt disease is a dangerous pine disease globally. We used Masson pine (Pinus massoniana) clones, selected through traditional breeding and testing for 20 years, to study the molecular mechanism of their high resistance to pine wood nematodes (PWN,Bursaphelenchus xylophilus). Nine strains of seedlings of genetically stable Masson pine screened from different families with high resistance to PWN were used. The same number of sensitive clones were used as susceptible controls. Total proteins were extracted for tandem mass tag (TMT) quantitative proteomic analysis. The key proteins were verified by parallel reaction monitoring (PRM). A threshold of upregulation greater than 1.3-fold or downregulation greater than 0.3-fold was considered significant in highly resistant strains versus sensitive strains. A total of 3491 proteins were identified from the seedling tissues, among which 2783 proteins contained quantitative information. A total of 42 proteins were upregulated and 96 proteins were downregulated in the resistant strains. Functional enrichment analysis found significant differences in the proteins with pectin esterase activity or peroxidase activity. The proteins participating in salicylic acid metabolism, antioxidant stress reaction, polysaccharide degradation, glucose acid ester sheath lipid biosynthesis, and the sugar glycosaminoglycan degradation pathway were also changed significantly. The PRM results showed that pectin acetyl esterase, carbonic anhydrase, peroxidase, and chitinase were significantly downregulated, while aspartic protease was significantly upregulated, which was consistent with the proteomic data. These results suggest that Masson pine can degrade nematode-related proteins by increasing protease to inhibit their infestation, and can enhance the resistance of Masson pine to PWN by downregulating carbon metabolism to limit the carbon available to PWN or for involvement in cell wall components or tissue softening. Most of the downregulated proteins are supposed to act as an alternative mechanism for latter enhancement after pathogen attacks. The highly resistant Masson pine, very likely, harbors multiple pathways, both passive and active, to defend against PWN infestation.
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Affiliation(s)
- Jingbin GAO
- Anhui Vocational & Technical College of Forestry, Hefei, China
- State Key Laboratory of the National Forestry and Grassland Administration for Pine Wood Nematode Disease Prevention and Control Technology, Hefei, China
| | - Ting PAN
- State Key Laboratory of the National Forestry and Grassland Administration for Pine Wood Nematode Disease Prevention and Control Technology, Hefei, China
- Anhui Academy of Forestry, Hefei, China
| | - Xuelian CHEN
- State Key Laboratory of the National Forestry and Grassland Administration for Pine Wood Nematode Disease Prevention and Control Technology, Hefei, China
- Anhui Academy of Forestry, Hefei, China
| | - Qiang Wei
- State Key Laboratory of the National Forestry and Grassland Administration for Pine Wood Nematode Disease Prevention and Control Technology, Hefei, China
- Anhui Academy of Forestry, Hefei, China
| | - Liuyi Xu
- State Key Laboratory of the National Forestry and Grassland Administration for Pine Wood Nematode Disease Prevention and Control Technology, Hefei, China
- Anhui Academy of Forestry, Hefei, China
- * E-mail:
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Chen J, Han S, Li S, Wang M, Zhu H, Qiao T, Lin T, Zhu T. Comparative Transcriptomics and Gene Knockout Reveal Virulence Factors of Neofusicoccum parvum in Walnut. Front Microbiol 2022; 13:926620. [PMID: 35910616 PMCID: PMC9335079 DOI: 10.3389/fmicb.2022.926620] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 06/17/2022] [Indexed: 12/11/2022] Open
Abstract
Neofusicoccum parvum can cause stem and branch blight of walnut (Juglans spp.), resulting in great economic losses and ecological damage. A total of two strains of N. parvum were subjected to RNA-sequencing after being fed on different substrates, sterile water (K1/K2), and walnut (T1/T2), and the function of ABC1 was verified by gene knockout. There were 1,834, 338, and 878 differentially expressed genes (DEGs) between the K1 vs. K2, T1 vs. K1, and T2 vs. K2 comparison groups, respectively. The expression changes in thirty DEGs were verified by fluorescent quantitative PCR. These thirty DEGs showed the same expression patterns under both RNA-seq and PCR. In addition, ΔNpABC1 showed weaker virulence due to gene knockout, and the complementary strain NpABC1c showed the same virulence as the wild-type strain. Compared to the wild-type and complemented strains, the relative growth of ΔNpABC1 was significantly decreased when grown with H2O2, NaCl, Congo red, chloramphenicol, MnSO4, and CuSO4. The disease index of walnuts infected by the mutants was significantly lower than those infected by the wild-type and complementary strains. This result indicates that ABC1 gene is required for the stress response and virulence of N. parvum and may be involved in heavy metal resistance.
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Affiliation(s)
- Jie Chen
- Department of Forest Protection, College of Forestry, Sichuan Agricultural University, Chengdu, China
| | - Shan Han
- Department of Forest Protection, College of Forestry, Sichuan Agricultural University, Chengdu, China
| | - Shujiang Li
- Department of Forest Protection, College of Forestry, Sichuan Agricultural University, Chengdu, China
| | - Ming Wang
- Ecological Institute, Academy of Sichuan Forestry and Grassland Inventory and Planning, Chengdu, China
| | - Hanmingyue Zhu
- Department of Forest Protection, College of Forestry, Sichuan Agricultural University, Chengdu, China
| | - Tianmin Qiao
- Department of Forest Protection, College of Forestry, Sichuan Agricultural University, Chengdu, China
| | - Tiantian Lin
- Department of Forest Protection, College of Forestry, Sichuan Agricultural University, Chengdu, China
| | - Tianhui Zhu
- Department of Forest Protection, College of Forestry, Sichuan Agricultural University, Chengdu, China
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Wram CL, Hesse CN, Zasada IA. Transcriptional response of Meloidogyne incognita to non-fumigant nematicides. Sci Rep 2022; 12:9814. [PMID: 35697824 PMCID: PMC9192767 DOI: 10.1038/s41598-022-13815-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 05/27/2022] [Indexed: 11/12/2022] Open
Abstract
There is limited research about the impacts of new nematicides, including fluazaindolizine, fluopyram, and fluensulfone, on the plant-parasitic nematode Meloidogyne incognita, despite it being a pervasive agricultural pest. In this study, M. incognita second-stage juveniles were exposed for 24-h to fluensulfone, fluazaindolizine, fluopyram, and oxamyl and total RNA was extracted and sequenced using next-generation sequencing to determine gene expression. The effects of nematicide exposure on cellular detoxification pathways, common differentially expressed (DE) genes, and fatty acid and retinol-binding genes were examined. Fluopyram and oxamyl had the smallest impacts on the M. incognita transcriptome with 48 and 151 genes that were DE, respectively. These compounds also elicited a weak response in the cellular detoxification pathway and fatty acid and retinol-binding (FAR) genes. Fluensulfone and fluazaindolizine produced robust transcriptional responses with 1208 and 2611 DE genes, respectively. These compounds had strong impacts on cellular detoxification, causing differential regulation of transcription factors and genes in the detox pathway. These compounds strongly down-regulated FAR genes between 52-85%. Having a greater understanding of how these compounds function at a molecular level will help to promote proper stewardship, aid with nematicide discovery, and help to stay a step ahead of nematicide resistance.
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Affiliation(s)
- Catherine L Wram
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, 97331, USA.
| | - Cedar N Hesse
- USDA-ARS Horticultural Crops Research Unit, Corvallis, OR, 97330, USA
| | - Inga A Zasada
- USDA-ARS Horticultural Crops Research Unit, Corvallis, OR, 97330, USA
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Zhang ZY, Guan JY, Cao YR, Dai XY, Storey KB, Yu DN, Zhang JY. Mitogenome Analysis of Four Lamiinae Species (Coleoptera: Cerambycidae) and Gene Expression Responses by Monochamus alternatus When Infected with the Parasitic Nematode, Bursaphelenchus mucronatus. INSECTS 2021; 12:453. [PMID: 34069253 PMCID: PMC8157225 DOI: 10.3390/insects12050453] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 05/09/2021] [Accepted: 05/12/2021] [Indexed: 01/23/2023]
Abstract
We determined the mitochondrial gene sequence of Monochamus alternatus and three other mitogenomes of Lamiinae (Insect: Coleoptera: Cerambycidae) belonging to three genera (Aulaconotus, Apriona and Paraglenea) to enrich the mitochondrial genome database of Lamiinae and further explore the phylogenetic relationships within the subfamily. Phylogenetic trees of the Lamiinae were built using the Bayesian inference (BI) and maximum likelihood (ML) methods and the monophyly of Monochamus, Anoplophora, and Batocera genera was supported. Anoplophora chinensis, An. glabripennis and Aristobia reticulator were closely related, suggesting they may also be potential vectors for the transmission of the pine wood pathogenic nematode (Bursaphelenchus xylophilus) in addition to M. alternatus, a well-known vector of pine wilt disease. There is a special symbiotic relationship between M. alternatus and Bursaphelenchus xylophilus. As the native sympatric sibling species of B. xylophilus, B. mucronatus also has a specific relationship that is often overlooked. The analysis of mitochondrial gene expression aimed to explore the effect of B. mucronatus on the energy metabolism of the respiratory chain of M. alternatus adults. Using RT-qPCR, we determined and analyzed the expression of eight mitochondrial protein-coding genes (COI, COII, COIII, ND1, ND4, ND5, ATP6, and Cty b) between M. alternatus infected by B. mucronatus and M. alternatus without the nematode. Expression of all the eight mitochondrial genes were up-regulated, particularly the ND4 and ND5 gene, which were up-regulated by 4-5-fold (p < 0.01). Since longicorn beetles have immune responses to nematodes, we believe that their relationship should not be viewed as symbiotic, but classed as parasitic.
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Affiliation(s)
- Zi-Yi Zhang
- College of Chemistry and Life Science, Zhejiang Normal University, Jinhua 321004, China; (Z.-Y.Z.); (J.-Y.G.); (Y.-R.C.); (X.-Y.D.)
| | - Jia-Yin Guan
- College of Chemistry and Life Science, Zhejiang Normal University, Jinhua 321004, China; (Z.-Y.Z.); (J.-Y.G.); (Y.-R.C.); (X.-Y.D.)
| | - Yu-Rou Cao
- College of Chemistry and Life Science, Zhejiang Normal University, Jinhua 321004, China; (Z.-Y.Z.); (J.-Y.G.); (Y.-R.C.); (X.-Y.D.)
| | - Xin-Yi Dai
- College of Chemistry and Life Science, Zhejiang Normal University, Jinhua 321004, China; (Z.-Y.Z.); (J.-Y.G.); (Y.-R.C.); (X.-Y.D.)
| | - Kenneth B. Storey
- Department of Biology, Carleton University, Ottawa, ON K1S 5B6, Canada;
| | - Dan-Na Yu
- College of Chemistry and Life Science, Zhejiang Normal University, Jinhua 321004, China; (Z.-Y.Z.); (J.-Y.G.); (Y.-R.C.); (X.-Y.D.)
- Key Lab of Wildlife Biotechnology, Conservation and Utilization of Zhejiang Province, Zhejiang Normal University, Jinhua 321004, China
| | - Jia-Yong Zhang
- College of Chemistry and Life Science, Zhejiang Normal University, Jinhua 321004, China; (Z.-Y.Z.); (J.-Y.G.); (Y.-R.C.); (X.-Y.D.)
- Key Lab of Wildlife Biotechnology, Conservation and Utilization of Zhejiang Province, Zhejiang Normal University, Jinhua 321004, China
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Li J, Xu C, Yang S, Chen C, Tang S, Wang J, Xie H. A Venom Allergen-Like Protein, RsVAP, the First Discovered Effector Protein of Radopholus similis That Inhibits Plant Defense and Facilitates Parasitism. Int J Mol Sci 2021; 22:4782. [PMID: 33946385 PMCID: PMC8125365 DOI: 10.3390/ijms22094782] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 04/13/2021] [Accepted: 04/28/2021] [Indexed: 12/16/2022] Open
Abstract
Radopholus similis is a migratory endoparasitic nematode that is extremely harmful to host plants. Venom allergen-like proteins (VAPs) are members of the cysteine-rich secretory protein family that are widely present in plants and animals. In this study, we cloned a VAP gene from R. similis, designated as RsVAP. RsVAP contains an open reading frame of 1089 bp encoding 362 amino acids. RsVAP is specifically expressed in the esophageal gland, and the expression levels of RsVAP are significantly higher in juveniles than in other life stages of R. similis. This expression pattern of RsVAP was consistent with the biological characteristics of juveniles of R. similis, which have the ability of infection and are the main infection stages of R. similis. The pathogenicity and reproduction rate of R. similis in tomato was significantly attenuated after RsVAP was silenced. In tobacco leaves transiently expressing RsVAP, the pathogen-associated molecular pattern-triggered immunity (PTI) induced by a bacterial flagellin fragment (flg22) was inhibited, while the cell death induced by two sets of immune elicitors (BAX and Gpa2/RBP-1) was repressed. The RsVAP-interacting, ras-related protein RABA1d (LeRabA1d) was identified in tomato hosts by yeast two-hybrid and co-immunoprecipitation assays. RsVAP may interact with LeRabA1d to affect the host defense response, which in turn facilitates nematode infection. This study provides the first evidence for the inhibition of plant defense response by a VAP from migratory plant-parasitic nematodes, and, for the first time, the target protein of R. similis in its host was identified.
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Affiliation(s)
| | | | | | | | | | | | - Hui Xie
- Research Center of Nematodes of Plant Quarantine, Laboratory of Plant Nematology, Department of Plant Pathology/Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Plant Protection, South China Agricultural University, Guangzhou 510642, China; (J.L.); (C.X.); (S.Y.); (C.C.); (S.T.); (J.W.)
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Silva H, Anjo SI, Manadas B, Abrantes I, Fonseca L, Cardoso JMS. Comparative Analysis of Bursaphelenchus xylophilus Secretome Under Pinus pinaster and P. pinea Stimuli. FRONTIERS IN PLANT SCIENCE 2021; 12:668064. [PMID: 34046053 PMCID: PMC8144518 DOI: 10.3389/fpls.2021.668064] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 03/29/2021] [Indexed: 05/19/2023]
Abstract
The pinewood nematode (PWN), Bursaphelenchus xylophilus, the pine wilt disease's (PWD) causal agent, is a migratory endoparasitic nematode skilled to feed on pine tissues and on fungi that colonize the trees. In order to study B. xylophilus secretomes under the stimulus of pine species with different susceptibilities to disease, nematodes were exposed to aqueous pine extracts from Pinus pinaster (high-susceptible host) and P. pinea (low-susceptible host). Sequential windowed acquisition of all theoretical mass spectra (SWATH-MS) was used to determine relative changes in protein amounts between B. xylophilus secretions, and a total of 776 secreted proteins were quantified in both secretomes. From these, 22 proteins were found increased in the B. xylophilus secretome under the P. pinaster stimulus and 501 proteins increased under the P. pinea stimulus. Functional analyses of the 22 proteins found increased in the P. pinaster stimulus showed that proteins with peptidase, hydrolase, and antioxidant activities were the most represented. On the other hand, gene ontology (GO) enrichment analysis of the 501 proteins increased under the P. pinea stimulus revealed an enrichment of proteins with binding activity. The differences detected in the secretomes highlighted the diverse responses from the nematode to overcome host defenses with different susceptibilities and provide new clues on the mechanism behind the pathogenicity of this plant-parasitic nematode. Proteomic data are available via ProteomeXchange with identifier PXD024011.
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Affiliation(s)
- Hugo Silva
- University of Coimbra, Centre for Functional Ecology, Department of Life Sciences, Coimbra, Portugal
| | - Sandra I. Anjo
- CNC – Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Bruno Manadas
- CNC – Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Isabel Abrantes
- University of Coimbra, Centre for Functional Ecology, Department of Life Sciences, Coimbra, Portugal
| | - Luís Fonseca
- University of Coimbra, Centre for Functional Ecology, Department of Life Sciences, Coimbra, Portugal
| | - Joana M. S. Cardoso
- University of Coimbra, Centre for Functional Ecology, Department of Life Sciences, Coimbra, Portugal
- *Correspondence: Joana M. S. Cardoso,
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Li Y, Feng Y, Wang X, Cui J, Deng X, Zhang X. Adaptation of pine wood nematode Bursaphelenchus xylophilus to β-pinene stress. BMC Genomics 2020; 21:478. [PMID: 32660425 PMCID: PMC7358211 DOI: 10.1186/s12864-020-06876-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 07/01/2020] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND The pine wood nematode (PWN; Bursaphelenchus xylophilus) is the most damaging biological pest in pine forest ecosystems in China. However, the pathogenic mechanism remains unclear. Tracheid cavitation induced by excess metabolism of volatile terpenes is a typical characteristic of pine trees infected by B. xylophilus. β-pinene, one of the main volatile terpenes, influences PWN colonization and reproduction, stimulating pathogenicity during the early stages of infection. To elucidate the response mechanism of PWN to β-pinene, pathogenesis, mortality, and reproduction rate were investigated under different concentrations of β-pinene using a transcriptomics approach. RESULTS A low concentration of β-pinene (BL, C < 25.74 mg/ml) inhibited PWN reproduction, whereas a high concentration (BH, C > 128.7 mg/ml) promoted reproduction. Comparison of PWN expression profiles under low (BL, 21.66 mg/ml) and high (BH, 214.5 mg/ml) β-pinene concentrations at 48 h identified 659 and 418 differentially expressed genes (DEGs), respectively, compared with controls. Some key DEGs are potential regulators of β-pinene via detoxification metabolism (cytochrome P450, UDP-glucuronosyltransferases and short-chain dehydrogenases), ion channel/transporter activity (unc and ATP-binding cassette families), and nuclear receptor -related genes. Gene Ontology enrichment analysis of DEGs revealed metabolic processes as the most significant biological processes, and catalytic activity as the most significant molecular function for both BL and BH samples. Kyoto Encyclopedia of Genes and Genomes (KEGG) Orthology (KO) analysis showed that xenobiotics biodegradation and metabolism, carbohydrate metabolism, lipid metabolism, amino acid metabolism, metabolism of cofactors and vitamins, and transport and catabolism were the dominant terms in metabolism categories. CONCLUSION In addition to detoxification via reduction/oxidation (redox) activity, PWN responds to β-pinene through amino acid metabolism, carbohydrate metabolism, and other pathways including growth regulation and epidermal protein changes to overcome β-pinene stress. This study lays a foundation for further exploring the pathogenic mechanism of PWN.
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Affiliation(s)
- Yongxia Li
- Lab. of Forest Pathogen Integrated Biology, Research institute of Forestry New Technology, Chinese Academy of Forestry, Beijing, 100091 China
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, 210037 China
| | - Yuqian Feng
- Lab. of Forest Pathogen Integrated Biology, Research institute of Forestry New Technology, Chinese Academy of Forestry, Beijing, 100091 China
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, 210037 China
| | - Xuan Wang
- Lab. of Forest Pathogen Integrated Biology, Research institute of Forestry New Technology, Chinese Academy of Forestry, Beijing, 100091 China
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, 210037 China
| | - Jing Cui
- Lab. of Forest Pathogen Integrated Biology, Research institute of Forestry New Technology, Chinese Academy of Forestry, Beijing, 100091 China
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, 210037 China
| | - Xun Deng
- Lab. of Forest Pathogen Integrated Biology, Research institute of Forestry New Technology, Chinese Academy of Forestry, Beijing, 100091 China
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, 210037 China
| | - Xingyao Zhang
- Lab. of Forest Pathogen Integrated Biology, Research institute of Forestry New Technology, Chinese Academy of Forestry, Beijing, 100091 China
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, 210037 China
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Wu S, Gao S, Wang S, Meng J, Wickham J, Luo S, Tan X, Yu H, Xiang Y, Hu S, Zhao L, Sun J. A Reference Genome of Bursaphelenchus mucronatus Provides New Resources for Revealing Its Displacement by Pinewood Nematode. Genes (Basel) 2020; 11:genes11050570. [PMID: 32438771 PMCID: PMC7288286 DOI: 10.3390/genes11050570] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 04/20/2020] [Accepted: 05/08/2020] [Indexed: 12/19/2022] Open
Abstract
The Bursaphelenchus mucronatus, which was highly similar with Bursaphelenchus xylophilus in terms of morphological characteristics and biological properties—but had weaker pathogenicity to forests—was a native species often displaced by B. xylophilus when occupying the same niche. Since the draft genome of the invasive B. xylophilus has been published, the absence of a reference genome of B. mucronatus still prevents us from understanding the molecular evidences behind competitive displacement. In this study, we employed Single Molecule, Real-Time (SMRT) sequencing and a Hi-C scaffolding approach to yield a near chromosome-level assembly of B. mucronatus, including six pseudo-chromosomes. The assembly size is 73 Mb, with scaffold N50 of 11.50 Mb and contig N50 of 1.48 Mb. Comparative genomics results showed high similarity between B. xylophilus and B. mucronatus. However, the losing of orphan genes and species-specific orthologous genes in B. mucronatus may indicate weaker adaptability to the environment. The gene family contractions of GPCRs (G Protein-Coupled Receptors) and cellulases in B. mucronatus may jointly contribute to its displacement by B. xylophilus. Overall, we introduced a valuable genomic resource for molecular and evolutionary studies of B. mucronatus, especially for studying the competitive displacement by the pinewood nematode, which could help us control the pathogenicity of pine wilt diseases.
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Affiliation(s)
- Shuangyang Wu
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; (S.W.); (J.M.); (J.W.); (Y.X.); (L.Z.)
| | - Shenghan Gao
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; (S.G.); (S.W.); (S.L.); (X.T.); (H.Y.); (S.H.)
| | - Sen Wang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; (S.G.); (S.W.); (S.L.); (X.T.); (H.Y.); (S.H.)
| | - Jie Meng
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; (S.W.); (J.M.); (J.W.); (Y.X.); (L.Z.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jacob Wickham
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; (S.W.); (J.M.); (J.W.); (Y.X.); (L.Z.)
| | - Sainan Luo
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; (S.G.); (S.W.); (S.L.); (X.T.); (H.Y.); (S.H.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xinyu Tan
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; (S.G.); (S.W.); (S.L.); (X.T.); (H.Y.); (S.H.)
| | - Haiying Yu
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; (S.G.); (S.W.); (S.L.); (X.T.); (H.Y.); (S.H.)
| | - Yujia Xiang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; (S.W.); (J.M.); (J.W.); (Y.X.); (L.Z.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Songnian Hu
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; (S.G.); (S.W.); (S.L.); (X.T.); (H.Y.); (S.H.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lilin Zhao
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; (S.W.); (J.M.); (J.W.); (Y.X.); (L.Z.)
| | - Jianghua Sun
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; (S.W.); (J.M.); (J.W.); (Y.X.); (L.Z.)
- University of Chinese Academy of Sciences, Beijing 100049, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing 100049, China
- Correspondence: ; Tel.: +86-10-64807121
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11
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Zhang W, Yu H, Lv Y, Bushley KE, Wickham JD, Gao S, Hu S, Zhao L, Sun J. Gene family expansion of pinewood nematode to detoxify its host defence chemicals. Mol Ecol 2020; 29:940-955. [DOI: 10.1111/mec.15378] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 02/02/2020] [Accepted: 02/02/2020] [Indexed: 02/07/2023]
Affiliation(s)
- Wei Zhang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of Zoology Chinese Academy of Sciences Beijing China
- Laboratory of Forest Pathogen Integrated Biology Research Institute of Forestry New Technology Chinese Academy of Forestry Beijing China
| | - Haiying Yu
- State Key Laboratory of Microbial Resources Institute of Microbiology Chinese Academy of Sciences Beijing China
| | - Yunxue Lv
- State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of Zoology Chinese Academy of Sciences Beijing China
| | - Kathryn E. Bushley
- Department of Plant and Microbial Biology University of Minnesota Twin Cities Saint Paul MN USA
| | - Jacob D. Wickham
- State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of Zoology Chinese Academy of Sciences Beijing China
| | - Shenghan Gao
- State Key Laboratory of Microbial Resources Institute of Microbiology Chinese Academy of Sciences Beijing China
| | - Songnian Hu
- State Key Laboratory of Microbial Resources Institute of Microbiology Chinese Academy of Sciences Beijing China
| | - Lilin Zhao
- State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of Zoology Chinese Academy of Sciences Beijing China
- CAS Center for Excellence in Biotic Interactions University of Chinese Academy of Sciences Beijing China
| | - Jianghua Sun
- State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of Zoology Chinese Academy of Sciences Beijing China
- CAS Center for Excellence in Biotic Interactions University of Chinese Academy of Sciences Beijing China
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12
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Lu F, Guo K, Chen A, Chen S, Lin H, Zhou X. Transcriptomic profiling of effects of emamectin benzoate on the pine wood nematode Bursaphelenchus xylophilus. PEST MANAGEMENT SCIENCE 2020; 76:747-757. [PMID: 31386282 DOI: 10.1002/ps.5575] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 07/25/2019] [Accepted: 08/01/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND Emamectin benzoate (EB) has recently been successfully applied as a trunk injection for preventative control of the pine wilt disease (PWD) caused by Bursaphelenchus xylophilus (Steiner & Buhrer) Nickle. Here, a whole-organism transcriptomic analysis provides comprehensive insights into the adverse effects of EB on B. xylophilus. RESULTS A large set of differentially expressed genes (DEGs) were found, demonstrating the antagonistic effects of EB on B. xylophilus embryonic and larval development, reproduction, nervous and motor systems, and pathogenesis. In toxicity assays with EB, the number of eggs laid, hatching rate, thrashing frequency, and developmental rate of B. xylophilus were significantly suppressed at low concentrations (0.1 μg mL-1 ). Moreover, the transcriptional changes validated by real-time quantitative PCR showed downregulated transcript levels of the genes encoding pectate lyases, β-1,4-endoglucanases, and upregulated the genes encoding glutamate-gated chloride channel, γ-aminobutyric acid type β receptor, uridine 5'-diphospho-glucuronosyl transferase, ATP-binding cassette transporter. The potential responses of B. xylophilus to EB included the upregulation of several genes putatively contributing to oocyte protection, stem cell renewal, and xenobiotic degradation, implying the potential for drug resistance to develop. CONCLUSION Our findings further our understanding of the effects of EB for managing the PWD and may help to improve the pesticide-use strategies for controlling B. xylophilus. © 2019 Society of Chemical Industry.
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Affiliation(s)
- Feng Lu
- Collaborative Innovation Center of Zhejiang Green Pesticide, State key Laboratory of Subtropical Silviculture, School of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou, People's Republic of China
| | - Kai Guo
- Collaborative Innovation Center of Zhejiang Green Pesticide, State key Laboratory of Subtropical Silviculture, School of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou, People's Republic of China
| | - Anliang Chen
- Collaborative Innovation Center of Zhejiang Green Pesticide, State key Laboratory of Subtropical Silviculture, School of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou, People's Republic of China
| | - Shani Chen
- Collaborative Innovation Center of Zhejiang Green Pesticide, State key Laboratory of Subtropical Silviculture, School of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou, People's Republic of China
| | - Haiping Lin
- Collaborative Innovation Center of Zhejiang Green Pesticide, State key Laboratory of Subtropical Silviculture, School of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou, People's Republic of China
| | - Xiang Zhou
- Collaborative Innovation Center of Zhejiang Green Pesticide, State key Laboratory of Subtropical Silviculture, School of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou, People's Republic of China
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13
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Wang F, Chen Q, Zhang R, Li D, Ling Y, Song R. The anti-phytoalexin gene Bx-cathepsin W supports the survival of Bursaphelenchus xylophilus under Pinus massoniana phytoalexin stress. BMC Genomics 2019; 20:779. [PMID: 31655568 PMCID: PMC6815438 DOI: 10.1186/s12864-019-6167-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 10/02/2019] [Indexed: 11/10/2022] Open
Abstract
Background Pine trees challenged by Bursaphelenchus xylophilus invasion produce phytoalexins to combat this nematode. Nevertheless, the phytoalexins of Asian pine trees are ineffective against B. xylophilus. The anti-phytoalexin genes of B. xylophilus disable almost all Asian pine phytoalexins, which has allowed B. xylophilus to devastate pine forests in eastern Asia over the last four decades. However, to date, the factors that stimulate anti-phytoalexin gene expression and the mechanisms by which these genes act are not well understood. Results Here, we described anti-phytoalexin genes in B. xylophilus using transcriptomic and bioinformatics analyses. The genes that were induced by both Pinus massoniana and carvone and had similarly elevated expression trends were considered anti-phytoalexin genes. Altogether, 187 anti-phytoalexin genes were identified, including 4 cathepsin genes. KEGG pathway enrichment indicated that those cathepsins were related to the Lysosome pathway. Since cathepsins help to maintain metabolic homeostasis by participating in the degradation of heterophagic and autophagic material, the lysosomal cathepsin gene Bx-cathepsin W was cloned and characterized. The results of the RNAi assessment indicated that the knockdown of Bx-cathepsin W reduced the survival rates of B. xylophilus under carvone or P. massoniana stress. The correlation between Bx-cathepsin W and the susceptibility of pines showed that Bx-cathepsin W might help improve the anti-phytotoxin ability of B. xylophilus. Conclusions The results indicated that the anti-phytoalexin gene Bx-cathepsin W supported the survival of B. xylophilus under P. massoniana phytoalexin stress. The cDNA library sequencing, differentially expressed gene identification, and WGCNA algorithm analysis provided insight at a systemic level into the gene regulation of B. xylophilus in response to the immune reaction of P. massoniana. These results will lead to a better understanding of the function of nematode defenses in host innate immunity.
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Affiliation(s)
- Feng Wang
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, School of Forestry, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China
| | - Qiaoli Chen
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, School of Forestry, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China
| | - Ruizhi Zhang
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, School of Forestry, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China
| | - Danlei Li
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, School of Forestry, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China
| | - Yaming Ling
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, School of Forestry, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China
| | - Ruiqing Song
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, School of Forestry, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China.
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Wang X, Yu Y, Ge J, Xie B, Zhu S, Cheng X. Effects of α-pinene on the pinewood nematode (Bursaphelenchus xylophilus) and its symbiotic bacteria. PLoS One 2019; 14:e0221099. [PMID: 31425544 PMCID: PMC6699699 DOI: 10.1371/journal.pone.0221099] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 07/30/2019] [Indexed: 11/18/2022] Open
Abstract
The pinewood nematode (PWN), Bursaphelenchus xylophilus, is an important plant-parasitic nematode that can cause severe mortality of pine trees. This PWN-induced harm to plants may be closely related to the abundance and diversity of the symbiotic microorganisms of the parasitic nematode. In this study, nematodes were divided into untreated and antibiotic-treated groups. Nematodes were treated by fumigation with different amounts of α-pinene, and the resultant mortality rates were analyzed statistically. Concentrations of symbiotic bacteria were calculated as colony-forming units per nematode. High-throughput sequencing was used to investigate the bacterial community structure. The results showed that the mortality of nematodes increased slightly with an increasing concentration of α-pinene, and nematodes untreated with antibiotics were more sensitive to α-pinene than those treated with antibiotics. The highest abundance of symbiotic bacteria was obtained via medium and low levels of α-pinene, but for which community diversity was the lowest (Shannon and Simpson indexes). The proportion of Pseudomonas spp. in the symbiotic bacteria of nematodes without antibiotics was relatively high (more than 70%), while that of Stenotrophomonas spp. was low (6%–20%). However, the proportion of Stenotrophomonas spp. was larger than that of Pseudomonas spp in the symbiotic bacteria associated with the antibiotic-treated nematodes. Pseudomonas sp. increased after pinene treatment, whereas Stenotrophomonas spp. decreased. These results indicate that although α-pinene has low toxicity to PWNs over a short time period, α-pinene ultimately influences the abundance and community diversity of the symbiotic bacteria of these nematodes; this influence may potentially disturb the development and reproduction of nematodes in the process of infecting pine trees.
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Affiliation(s)
- Xu Wang
- College of Life Sciences, Beijing Normal University, Beijing, China
- Chinese Academy of Inspection and Quarantine, Beijing, China
| | - Yanxue Yu
- Chinese Academy of Inspection and Quarantine, Beijing, China
| | - Jianjun Ge
- Chinese Academy of Inspection and Quarantine, Beijing, China
| | - Bingyan Xie
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Shuifang Zhu
- Chinese Academy of Inspection and Quarantine, Beijing, China
| | - Xinyue Cheng
- College of Life Sciences, Beijing Normal University, Beijing, China
- * E-mail:
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Xue Q, Xiang Y, Wu XQ, Li MJ. Bacterial Communities and Virulence Associated with Pine Wood Nematode Bursaphelenchus xylophilus from Different Pinus spp. Int J Mol Sci 2019; 20:ijms20133342. [PMID: 31284685 PMCID: PMC6650965 DOI: 10.3390/ijms20133342] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 06/29/2019] [Accepted: 07/03/2019] [Indexed: 12/27/2022] Open
Abstract
Bursaphelenchus xylophilus, the causal agent of pine wilt disease, is a destructive threat to pine forests. The role of bacteria associated with B. xylophilus in pine wilt disease has attracted widespread attention. This study investigated variation in bacterial communities and the virulence of surface-sterilized B. xylophilus from different Pinus spp. The predominant culturable bacteria of nematodes from different pines were Stenotrophomonas and Pseudomonas. Biolog EcoPlate analysis showed that metabolic diversity of bacteria in B. xylophilus from P. massoniana was the highest, followed by P. thunbergii and P. densiflora. High-throughput sequencing analysis indicated that bacterial diversity and community structure in nematodes from the different pine species varied, and the dominant bacteria were Stenotrophomonas and Elizabethkingia. The virulence determination of B. xylophilus showed that the nematodes from P. massoniana had the greatest virulence, followed by the nematodes from P. thunbergii and P. densiflora. After the nematodes were inoculated onto P. thunbergii, the relative abundance of the predominant bacteria changed greatly, and some new bacterial species emerged. Meanwhile, the virulence of all the nematode isolates increased after passage through P. thunbergii. These inferred that some bacteria associated with B. xylophilus isolated from different pine species might be helpful to adjust the PWN’s parasitic adaptability.
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Affiliation(s)
- Qi Xue
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, Jiangsu 210037, China
- Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing Forestry University, Nanjing, Jiangsu 210037, China
| | - Yang Xiang
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, Jiangsu 210037, China
- Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing Forestry University, Nanjing, Jiangsu 210037, China
| | - Xiao-Qin Wu
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, Jiangsu 210037, China.
- Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing Forestry University, Nanjing, Jiangsu 210037, China.
| | - Ming-Jie Li
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, Jiangsu 210037, China
- Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing Forestry University, Nanjing, Jiangsu 210037, China
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Li Y, Meng F, Deng X, Wang X, Feng Y, Zhang W, Pan L, Zhang X. Comparative Transcriptome Analysis of the Pinewood Nematode Bursaphelenchus xylophilus Reveals the Molecular Mechanism Underlying Its Defense Response to Host-Derived α-pinene. Int J Mol Sci 2019; 20:E911. [PMID: 30791528 PMCID: PMC6412324 DOI: 10.3390/ijms20040911] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 02/10/2019] [Accepted: 02/16/2019] [Indexed: 12/20/2022] Open
Abstract
Bursaphelenchus xylophilus is fatal to the pine trees around the world. The production of the pine tree secondary metabolite gradually increases in response to a B. xylophilus infestation, via a stress reaction mechanism(s). α-pinene is needed to combat the early stages of B. xylophilus infection and colonization, and to counter its pathogenesis. Therefore, research is needed to characterize the underlying molecular response(s) of B. xylophilus to resist α-pinene. We examined the effects of different concentrations of α-pinene on the mortality and reproduction rate of B. xylophilus in vitro. The molecular response by which B. xylophilus resists α-pinene was examined via comparative transcriptomics of the nematode. Notably, B. xylophilus genes involved in detoxification, transport, and receptor activities were differentially expressed in response to two different concentrations of α-pinene compared with control. Our results contribute to our understanding of the molecular mechanisms by which B. xylophilus responds to monoterpenes in general, and the pathogenesis of B. xylophilus.
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Affiliation(s)
- Yongxia Li
- Laboratory of Forest Pathogen Integrated Biology, Research Institute of Forestry New Technology, Chinese Academy of Forestry, Beijing 100091, China.
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China.
| | - Fanli Meng
- Laboratory of Forest Pathogen Integrated Biology, Research Institute of Forestry New Technology, Chinese Academy of Forestry, Beijing 100091, China.
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China.
| | - Xun Deng
- Laboratory of Forest Pathogen Integrated Biology, Research Institute of Forestry New Technology, Chinese Academy of Forestry, Beijing 100091, China.
| | - Xuan Wang
- Laboratory of Forest Pathogen Integrated Biology, Research Institute of Forestry New Technology, Chinese Academy of Forestry, Beijing 100091, China.
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China.
| | - Yuqian Feng
- Laboratory of Forest Pathogen Integrated Biology, Research Institute of Forestry New Technology, Chinese Academy of Forestry, Beijing 100091, China.
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China.
| | - Wei Zhang
- Laboratory of Forest Pathogen Integrated Biology, Research Institute of Forestry New Technology, Chinese Academy of Forestry, Beijing 100091, China.
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China.
| | - Long Pan
- Laboratory of Forest Pathogen Integrated Biology, Research Institute of Forestry New Technology, Chinese Academy of Forestry, Beijing 100091, China.
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China.
| | - Xingyao Zhang
- Laboratory of Forest Pathogen Integrated Biology, Research Institute of Forestry New Technology, Chinese Academy of Forestry, Beijing 100091, China.
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China.
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Secreted venom allergen-like proteins of helminths: Conserved modulators of host responses in animals and plants. PLoS Pathog 2018; 14:e1007300. [PMID: 30335852 PMCID: PMC6193718 DOI: 10.1371/journal.ppat.1007300] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Despite causing considerable damage to host tissue at the onset of parasitism, invasive helminths establish remarkably persistent infections in both animals and plants. Secretions released by these obligate parasites during host invasion are thought to be crucial for their persistence in infection. Helminth secretions are complex mixtures of molecules, most of which have unknown molecular targets and functions in host cells or tissues. Although the habitats of animal- and plant-parasitic helminths are very distinct, their secretions share the presence of a structurally conserved group of proteins called venom allergen-like proteins (VALs). Helminths abundantly secrete VALs during several stages of parasitism while inflicting extensive damage to host tissue. The tight association between the secretion of VALs and the onset of parasitism has triggered a particular interest in this group of proteins, as improved knowledge on their biological functions may assist in designing novel protection strategies against parasites in humans, livestock, and important food crops.
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18
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Zhou L, Chen F, Ye J, Pan H. Selection of Reliable Reference Genes for RT-qPCR Analysis of Bursaphelenchus mucronatus Gene Expression From Different Habitats and Developmental Stages. Front Genet 2018; 9:269. [PMID: 30083182 PMCID: PMC6064934 DOI: 10.3389/fgene.2018.00269] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 07/02/2018] [Indexed: 12/13/2022] Open
Abstract
Quantitative reverse transcription polymerase chain reaction (RT-qPCR), a sensitive technique for gene expression analysis, depends on the stability of the reference genes used for data normalization under different experimental conditions. Bursaphelenchus mucronatus, a pine-parasitic nematode varying in virulence, is widely distributed in natural pine forests throughout the northern hemisphere, but has not been investigated with respect to the identification of reference genes suitable for the normalization of RT-qPCR data. In the present study, eight candidate reference genes were analyzed in B. mucronatus under different habitat conditions and at different developmental stages. The expression stability of these genes was assessed by geNorm, NormFinder, BestKeeper, delta Cq, and RefFinder algorithms. In general, our results identified encoding beta-tubulin as the most stable gene. Moreover, pairwise analysis showed that three reference genes were sufficient to normalize the gene expression data under each set of conditions, with genes encoding beta-tubulin, 18S ribosomal RNA and ubiquitin-conjugating enzyme being the most suitable reference genes for different habitat conditions, whereas genes encoding beta-tubulin, histone, and 18S ribosomal RNA exhibited the most stable expression at different developmental stages. Validation of the selected reference genes was performed by profiling the expression of the fatty acid- and retinol-binding protein gene in different habitats, and by profiling the expression of the arginine kinase gene at different developmental stages. This first systematic analysis for the selection of suitable reference genes for RT-qPCR in B. mucronatus will facilitate future functional analyses and deep mining of genetic resources in this nematode.
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Affiliation(s)
| | - Fengmao Chen
- Collaborative Innovation Center of Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, China
| | - Jianren Ye
- Collaborative Innovation Center of Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, China
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Kerry MJ, Embretson SE. An Experimental Evaluation of Competing Age-Predictions of Future Time Perspective between Workplace and Retirement Domains. Front Psychol 2018; 8:2316. [PMID: 29375435 PMCID: PMC5767307 DOI: 10.3389/fpsyg.2017.02316] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 12/20/2017] [Indexed: 11/25/2022] Open
Abstract
Future time perspective (FTP) is defined as "perceptions of the future as being limited or open-ended" (Lang and Carstensen, 2002; p. 125). The construct figures prominently in both workplace and retirement domains, but the age-predictions are competing: Workplace research predicts decreasing FTP age-change, in contrast, retirement scholars predict increasing FTP age-change. For the first time, these competing predictions are pitted in an experimental manipulation of subjective life expectancy (SLE). A sample of N = 207 older adults (age 45-60) working full-time (>30-h/week) were randomly assigned to SLE questions framed as either 'Live-to' or 'Die-by' to evaluate competing predictions for FTP. Results indicate general support for decreasing age-change in FTP, indicated by independent-sample t-tests showing lower FTP in the 'Die-by' framing condition. Further general-linear model analyses were conducted to test for interaction effects of retirement planning with experimental framings on FTP and intended retirement; While retirement planning buffered FTP's decrease, simple-effects also revealed that retirement planning increased intentions for sooner retirement, but lack of planning increased intentions for later retirement. Discussion centers on practical implications of our findings and consequences validity evidence in future empirical research of FTP in both workplace and retirement domains.
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Affiliation(s)
| | - Susan E. Embretson
- Quantitative Psychology, Georgia Institute of Technology, Atlanta, GA, United States
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Cardoso JMS, Anjo SI, Fonseca L, Egas C, Manadas B, Abrantes I. Bursaphelenchus xylophilus and B. mucronatus secretomes: a comparative proteomic analysis. Sci Rep 2016; 6:39007. [PMID: 27941947 PMCID: PMC5150578 DOI: 10.1038/srep39007] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 11/16/2016] [Indexed: 11/09/2022] Open
Abstract
The pinewood nematode, Bursaphelenchus xylophilus, recognized as a worldwide major forest pest, is a migratory endoparasitic nematode with capacity to feed on pine tissues and also on fungi colonizing the trees. Bursaphelenchus mucronatus, the closest related species, differs from B. xylophilus on its pathogenicity, making this nematode a good candidate for comparative analyses. Secretome profiles of B. xylophilus and B. mucronatus were obtained and proteomic differences were evaluated by quantitative SWATH-MS. From the 681 proteins initially identified, 422 were quantified and compared between B. xylophilus and B. mucronatus secretomes and from these, 243 proteins were found differentially regulated: 158 and 85 proteins were increased in B. xylophilus and B. mucronatus secretomes, respectively. While increased proteins in B. xylophilus secretome revealed a strong enrichment in proteins with peptidase activity, the increased proteins in B. mucronatus secretome were mainly related to oxidative stress responses. The changes in peptidases were evaluated at the transcription level by RT-qPCR, revealing a correlation between the mRNA levels of four cysteine peptidases with secretion levels. The analysis presented expands our knowledge about molecular basis of B. xylophilus and B. mucronatus hosts interaction and supports the hypothesis of a key role of secreted peptidases in B. xylophilus pathogenicity.
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Affiliation(s)
- Joana M. S. Cardoso
- CFE - Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Calçada Martim de Freitas, 3000-456 Coimbra, Portugal
| | - Sandra I. Anjo
- Faculty of Sciences and Technology, University of Coimbra, 3030-790 Coimbra, Portugal
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal
| | - Luís Fonseca
- CFE - Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Calçada Martim de Freitas, 3000-456 Coimbra, Portugal
| | - Conceição Egas
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal
| | - Bruno Manadas
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal
| | - Isabel Abrantes
- CFE - Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Calçada Martim de Freitas, 3000-456 Coimbra, Portugal
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21
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Identifying Virulence-Associated Genes Using Transcriptomic and Proteomic Association Analyses of the Plant Parasitic Nematode Bursaphelenchus mucronatus. Int J Mol Sci 2016; 17:ijms17091492. [PMID: 27618012 PMCID: PMC5037770 DOI: 10.3390/ijms17091492] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2016] [Revised: 08/05/2016] [Accepted: 08/23/2016] [Indexed: 01/05/2023] Open
Abstract
Bursaphelenchus mucronatus (B. mucronatus) isolates that originate from different regions may vary in their virulence, but their virulence-associated genes and proteins are poorly understood. Thus, we conducted an integrated study coupling RNA-Seq and isobaric tags for relative and absolute quantitation (iTRAQ) to analyse transcriptomic and proteomic data of highly and weakly virulent B. mucronatus isolates during the pathogenic processes. Approximately 40,000 annotated unigenes and 5000 proteins were gained from the isolates. When we matched all of the proteins with their detected transcripts, a low correlation coefficient of r = 0.138 was found, indicating probable post-transcriptional gene regulation involved in the pathogenic processes. A functional analysis showed that five differentially expressed proteins which were all highly expressed in the highly virulent isolate were involved in the pathogenic processes of nematodes. Peroxiredoxin, fatty acid- and retinol-binding protein, and glutathione peroxidase relate to resistance against plant defence responses, while β-1,4-endoglucanase and expansin are associated with the breakdown of plant cell walls. Thus, the pathogenesis of B. mucronatus depends on its successful survival in host plants. Our work adds to the understanding of B. mucronatus' pathogenesis, and will aid in controlling B. mucronatus and other pinewood nematode species complexes in the future.
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22
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He LX, Wu XQ, Xue Q, Qiu XW. Effects of Endobacterium (Stenotrophomonas maltophilia) on Pathogenesis-Related Gene Expression of Pine Wood Nematode (Bursaphelenchus xylophilus) and Pine Wilt Disease. Int J Mol Sci 2016; 17:E778. [PMID: 27231904 PMCID: PMC4926329 DOI: 10.3390/ijms17060778] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 05/13/2016] [Accepted: 05/16/2016] [Indexed: 02/06/2023] Open
Abstract
Pine wilt disease (PWD) caused by the pine wood nematode (PWN), Bursaphelenchus xylophilus, is responsible for devastating epidemics in pine trees in Asia and Europe. Recent studies showed that bacteria carried by the PWN might be involved in PWD. However, the molecular mechanism of the interaction between bacteria and the PWN remained unclear. Now that the whole genome of B. xylophilus (Bursaphelenchus xylophilus) is published, transcriptome analysis is a unique method to study the role played by bacteria in PWN. In this study, the transcriptome of aseptic B. xylophilus, B. xylophilus treated with endobacterium (Stenotrophomonas maltophilia NSPmBx03) and fungus B. xylophilus were sequenced. We found that 61 genes were up-regulated and 830 were down-regulated in B. xylophilus after treatment with the endobacterium; 178 genes were up-regulated and 1122 were down-regulated in fungus B. xylophilus compared with aseptic B. xylophilus. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses were used to study the significantly changed biological functions and pathways for these differentially expressed genes. Many pathogenesis-related genes, including glutathinone S-transferase, pectate lyase, ATP-binding cassette transporter and cytochrome P450, were up-regulated after B. xylophilus were treated with the endobacterium. In addition, we found that bacteria enhanced the virulence of PWN. These findings indicate that endobacteria might play an important role in the development and virulence of PWN and will improve our understanding of the regulatory mechanisms involved in the interaction between bacteria and the PWN.
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Affiliation(s)
- Long-Xi He
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing 210037, China.
- Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing Forestry University, Nanjing 210037, China.
- Jiangxi Forest Pest Control and Quarantine Bureau, Nanchang 330038, China.
| | - Xiao-Qin Wu
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing 210037, China.
- Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing Forestry University, Nanjing 210037, China.
| | - Qi Xue
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing 210037, China.
- Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing Forestry University, Nanjing 210037, China.
| | - Xiu-Wen Qiu
- Poyang Lake Eco-economy Research Center, Jiujiang University, Jiujiang 332005, China.
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23
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Ding X, Ye J, Lin S, Wu X, Li D, Nian B. Deciphering the Molecular Variations of Pine Wood Nematode Bursaphelenchus xylophilus with Different Virulence. PLoS One 2016; 11:e0156040. [PMID: 27224277 PMCID: PMC4880305 DOI: 10.1371/journal.pone.0156040] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 05/09/2016] [Indexed: 12/22/2022] Open
Abstract
Bursaphelenchus xylophilus is the causative agent of pine wilt disease which has caused huge economic losses in many countries. It has been reported that two forms of pine wood nematodes existed in its native region, i.e., with strong virulence and weak virulence. However, little is known about the molecular differences between the two forms. To better understand their molecular variations, transcriptome and genome sequences of three strongly virulent and one weakly virulent strains were analyzed. We found 238 transcripts and 84 exons which showed notable changes between the two virulent forms. Functional analyses of both differentially expressed transcripts and exons indicated that different virulence strains showed dissimilar nematode growth, reproduction, and oxidoreductase activities. In addition, we also detected a small number of exon-skipping events in B. xylophilus. Meanwhile, 117 SNPs were identified as potential genetic markers in distinguishing the two forms. Four of them were further proved to have undergone allele specific expressions and possibly interrupted the target site of evolutionary conserved B. xylophilus miR-47. These particular SNPs were experimentally verified by including eight additional strains to ensure the validity of our sequencing results. These results could help researchers to better diagnose nematode species with different virulence and facilitate the control of pine wilt disease.
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Affiliation(s)
- Xiaolei Ding
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, Jiangsu, China.,Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing, Jiangsu, China
| | - Jianren Ye
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, Jiangsu, China.,Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing, Jiangsu, China
| | - Sixi Lin
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, Jiangsu, China.,Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing, Jiangsu, China
| | - Xiaoqin Wu
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, Jiangsu, China.,Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing, Jiangsu, China
| | - Dewei Li
- The Connecticut Agricultural Experiment Station Valley Laboratory, Windsor, Connecticut, 06095, United States of America.,Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, Jiangsu, China
| | - Bo Nian
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, Jiangsu, China.,Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing, Jiangsu, China
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Wang M, Wang D, Zhang X, Wang X, Liu W, Hou X, Huang X, Xie B, Cheng X. Double-stranded RNA-mediated interference of dumpy genes in Bursaphelenchus xylophilus by feeding on filamentous fungal transformants. Int J Parasitol 2016; 46:351-60. [PMID: 26953254 DOI: 10.1016/j.ijpara.2016.01.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Revised: 01/27/2016] [Accepted: 01/28/2016] [Indexed: 01/05/2023]
Abstract
RNA interference (RNAi) is a valuable tool for studying gene function in vivo and provides a functional genomics platform in a wide variety of organisms. The pinewood nematode, Bursaphelenchus xylophilus, is a prominent invasive plant-parasitic nematode and has become a serious worldwide threat to forest ecosystems. Presently, the complete genome sequence of B. xylophilus has been published, and research involving genome-wide functional analyses is likely to increase. In this study, we describe the construction of an effective silencing vector, pDH-RH, which contains a transcriptional unit for a hairpin loop structure. Utilising this vector, double-stranded (ds)RNAs with sequences homologous to the target genes can be expressed in a transformed filamentous fungus via Agrobacterium tumefaciens-mediated transformation technology, and can subsequently induce the knockdown of target gene mRNA expression in B. xylophilus by allowing the nematode to feed on the fungal transformants. Four dumpy genes (Bx-dpy-2, 4, 10 and 11) were used as targets to detect RNAi efficiency. By allowing the nematode to feed on target gene-transformed Fusarium oxysporum strains, target transcripts were knocked down 34-87% compared with those feeding on the wild-type strain as determined by real-time quantitative PCR (RT-qPCR). Morphological RNAi phenotypes were observed, displaying obviously reduced body length; weak dumpy or small (short and thin) body size; or general abnormalities. Moreover, compensatory regulation and non-specific silencing of dpy genes were found in B. xylophilus. Our results indicate that RNAi delivery by feeding in B. xylophilus is a successful technique. This platform may provide a new opportunity for undertaking RNAi-based, genome-wide gene functional studies in vitro in B. xylophilus. Moreover, as B. xylophilus feeds on endophytic fungi when a host has died, RNAi feeding technology will offer the prospect for developing a novel control strategy for the nematode. Furthermore, this platform may also be applicable to other parasitic nematodes that have a facultative, fungivorous habit.
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Affiliation(s)
- Meng Wang
- College of Life Sciences, Beijing Normal University, Beijing 100875, China
| | - Diandong Wang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China; Yangtze Normal University, Chongqing 408100, China
| | - Xi Zhang
- College of Life Sciences, Beijing Normal University, Beijing 100875, China
| | - Xu Wang
- College of Life Sciences, Beijing Normal University, Beijing 100875, China
| | - Wencui Liu
- College of Life Sciences, Beijing Normal University, Beijing 100875, China
| | - Xiaomeng Hou
- College of Life Sciences, Beijing Normal University, Beijing 100875, China
| | - Xiaoyin Huang
- College of Life Sciences, Beijing Normal University, Beijing 100875, China
| | - Bingyan Xie
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Xinyue Cheng
- College of Life Sciences, Beijing Normal University, Beijing 100875, China; Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Beijing 100875, China.
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25
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Espada M, Silva AC, Eves van den Akker S, Cock PJA, Mota M, Jones JT. Identification and characterization of parasitism genes from the pinewood nematode Bursaphelenchus xylophilus reveals a multilayered detoxification strategy. MOLECULAR PLANT PATHOLOGY 2016; 17:286-95. [PMID: 25981957 PMCID: PMC6638532 DOI: 10.1111/mpp.12280] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The migratory endoparasitic nematode Bursaphelenchus xylophilus, which is the causal agent of pine wilt disease, has phytophagous and mycetophagous phases during its life cycle. This highly unusual feature distinguishes it from other plant-parasitic nematodes and requires profound changes in biology between modes. During the phytophagous stage, the nematode migrates within pine trees, feeding on the contents of parenchymal cells. Like other plant pathogens, B. xylophilus secretes effectors from pharyngeal gland cells into the host during infection. We provide the first description of changes in the morphology of these gland cells between juvenile and adult life stages. Using a comparative transcriptomics approach and an effector identification pipeline, we identify numerous novel parasitism genes which may be important for the mediation of interactions of B. xylophilus with its host. In-depth characterization of all parasitism genes using in situ hybridization reveals two major categories of detoxification proteins, those specifically expressed in either the pharyngeal gland cells or the digestive system. These data suggest that B. xylophilus incorporates effectors in a multilayer detoxification strategy in order to protect itself from host defence responses during phytophagy.
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Affiliation(s)
- Margarida Espada
- NemaLab/ICAAM-Instituto de Ciências Agrárias e Ambientais Mediterrânicas, Universidade de Évora, Núcleo da Mitra, Ap. 94, 7002-554, Évora, Portugal
- Cell and Molecular Sciences Group/Information and Computer Sciences Group (PJAC), The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK
| | - Ana Cláudia Silva
- NemaLab/ICAAM-Instituto de Ciências Agrárias e Ambientais Mediterrânicas, Universidade de Évora, Núcleo da Mitra, Ap. 94, 7002-554, Évora, Portugal
- Cell and Molecular Sciences Group/Information and Computer Sciences Group (PJAC), The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK
- Biology Department, University of Gent, KL Ledeganckstraat 35, B9000, Gent, Belgium
| | | | - Peter J A Cock
- Cell and Molecular Sciences Group/Information and Computer Sciences Group (PJAC), The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK
| | - Manuel Mota
- NemaLab/ICAAM-Instituto de Ciências Agrárias e Ambientais Mediterrânicas, Universidade de Évora, Núcleo da Mitra, Ap. 94, 7002-554, Évora, Portugal
| | - John T Jones
- Cell and Molecular Sciences Group/Information and Computer Sciences Group (PJAC), The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK
- Biology Department, University of Gent, KL Ledeganckstraat 35, B9000, Gent, Belgium
- School of Biology, University of St Andrews, North Haugh, St Andrews, KY16 9TZ, UK
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26
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Nascimento FX, Hasegawa K, Mota M, Vicente CSL. Bacterial role in pine wilt disease development - review and future perspectives. ENVIRONMENTAL MICROBIOLOGY REPORTS 2015; 7:51-63. [PMID: 25139220 DOI: 10.1111/1758-2229.12202] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Accepted: 08/14/2014] [Indexed: 05/02/2023]
Abstract
Mutualistic and beneficial relationships between nematodes and bacteria are highly present in nature, mostly occurring because of nutritional dependence and pathogen protection, and intrinsically related with the environment, the ecological conditions and the nematode life stages. Thirty-four years have passed since the first hypothesis suggesting a bacterial role in pine wilt disease (PWD), associated with the pinewood nematode (PWN), Bursaphelenchus xylophilus. In 1980, researchers reported that bacteria associated with the PWN could produce toxins that lead to PWD development in pine seedlings. It was also suggested a double vector system for PWD, where bacteria were vectored by the PWN and the PWN vectored by an insect from the Monochamus genus. Presently, the specific involvement of bacteria in such complex disease is still controversial, even though the increased number of studies focused on the potential bacteria role has increased considerably. This review is an up-to-date comprehensive perspective and brings new insights on the role of PWN-associated bacteria in PWD.
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Affiliation(s)
- Francisco X Nascimento
- ICAAM - Instituto de Ciências Agrárias e Ambientais Mediterrânicas, Departamento de Biologia, Universidade de Évora, Núcleo da Mitra, Ap. 94, Évora, 7002-554, Portugal
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Cheng XY, Tian XL, Wang YS, Lin RM, Mao ZC, Chen N, Xie BY. Metagenomic analysis of the pinewood nematode microbiome reveals a symbiotic relationship critical for xenobiotics degradation. Sci Rep 2013; 3:1869. [PMID: 23694939 PMCID: PMC3660777 DOI: 10.1038/srep01869] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Accepted: 04/30/2013] [Indexed: 11/09/2022] Open
Abstract
Our recent research revealed that pinewood nematode (PWN) possesses few genes encoding enzymes for degrading α-pinene, which is the main compound in pine resin. In this study, we examined the role of PWN microbiome in xenobiotics detoxification by metagenomic and bacteria culture analyses. Functional annotation of metagenomes illustrated that benzoate degradation and its related metabolisms may provide the main metabolic pathways for xenobiotics detoxification in the microbiome, which is obviously different from that in PWN that uses cytochrome P450 metabolism as the main pathway for detoxification. The metabolic pathway of degrading α-pinene is complete in microbiome, but incomplete in PWN genome. Experimental analysis demonstrated that most of tested cultivable bacteria can not only survive the stress of 0.4% α-pinene, but also utilize α-pinene as carbon source for their growth. Our results indicate that PWN and its microbiome have established a potentially mutualistic symbiotic relationship with complementary pathways in detoxification metabolism.
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Affiliation(s)
- Xin-Yue Cheng
- College of Life Sciences, Beijing Normal University, Beijing, China
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