Publications
2012 |
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Articles de journaux |
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9. | Deleury, Emeline; Dubreuil, Géraldine; Elangovan, Namasivayam; Wajnberg, Eric; Reichhart, Jean-Marc; Gourbal, Benjamin; Duval, David; Baron, Olga Lucia; Gouzy, Jérôme; Coustau, Christine Specific versus non-specific immune responses in an invertebrate species evidenced by a comparative de novo sequencing study Article de journal PLoS ONE, 7 (3), p. e32512, 2012, ISSN: 1932-6203. Résumé | Liens | BibTeX | Étiquettes: Biomphalaria, Calmodulin, Cluster Analysis, Complementary, DNA, Expressed Sequence Tags, Ferritins, Gene Expression Profiling, Gene Expression Regulation, High-Throughput Nucleotide Sequencing, Immunity, Innate, Messenger, Pattern Recognition, Phylogeny, Receptors, RNA, Signal Transduction, Zinc Fingers @article{deleury_specific_2012, title = {Specific versus non-specific immune responses in an invertebrate species evidenced by a comparative de novo sequencing study}, author = { Emeline Deleury and Géraldine Dubreuil and Namasivayam Elangovan and Eric Wajnberg and Jean-Marc Reichhart and Benjamin Gourbal and David Duval and Olga Lucia Baron and Jérôme Gouzy and Christine Coustau}, doi = {10.1371/journal.pone.0032512}, issn = {1932-6203}, year = {2012}, date = {2012-01-01}, journal = {PLoS ONE}, volume = {7}, number = {3}, pages = {e32512}, abstract = {Our present understanding of the functioning and evolutionary history of invertebrate innate immunity derives mostly from studies on a few model species belonging to ecdysozoa. In particular, the characterization of signaling pathways dedicated to specific responses towards fungi and Gram-positive or Gram-negative bacteria in Drosophila melanogaster challenged our original view of a non-specific immunity in invertebrates. However, much remains to be elucidated from lophotrochozoan species. To investigate the global specificity of the immune response in the fresh-water snail Biomphalaria glabrata, we used massive Illumina sequencing of 5'-end cDNAs to compare expression profiles after challenge by Gram-positive or Gram-negative bacteria or after a yeast challenge. 5'-end cDNA sequencing of the libraries yielded over 12 millions high quality reads. To link these short reads to expressed genes, we prepared a reference transcriptomic database through automatic assembly and annotation of the 758,510 redundant sequences (ESTs, mRNAs) of B. glabrata available in public databases. Computational analysis of Illumina reads followed by multivariate analyses allowed identification of 1685 candidate transcripts differentially expressed after an immune challenge, with a two fold ratio between transcripts showing a challenge-specific expression versus a lower or non-specific differential expression. Differential expression has been validated using quantitative PCR for a subset of randomly selected candidates. Predicted functions of annotated candidates (approx. 700 unisequences) belonged to a large extend to similar functional categories or protein types. This work significantly expands upon previous gene discovery and expression studies on B. glabrata and suggests that responses to various pathogens may involve similar immune processes or signaling pathways but different genes belonging to multigenic families. These results raise the question of the importance of gene duplication and acquisition of paralog functional diversity in the evolution of specific invertebrate immune responses.}, keywords = {Biomphalaria, Calmodulin, Cluster Analysis, Complementary, DNA, Expressed Sequence Tags, Ferritins, Gene Expression Profiling, Gene Expression Regulation, High-Throughput Nucleotide Sequencing, Immunity, Innate, Messenger, Pattern Recognition, Phylogeny, Receptors, RNA, Signal Transduction, Zinc Fingers}, pubstate = {published}, tppubtype = {article} } Our present understanding of the functioning and evolutionary history of invertebrate innate immunity derives mostly from studies on a few model species belonging to ecdysozoa. In particular, the characterization of signaling pathways dedicated to specific responses towards fungi and Gram-positive or Gram-negative bacteria in Drosophila melanogaster challenged our original view of a non-specific immunity in invertebrates. However, much remains to be elucidated from lophotrochozoan species. To investigate the global specificity of the immune response in the fresh-water snail Biomphalaria glabrata, we used massive Illumina sequencing of 5'-end cDNAs to compare expression profiles after challenge by Gram-positive or Gram-negative bacteria or after a yeast challenge. 5'-end cDNA sequencing of the libraries yielded over 12 millions high quality reads. To link these short reads to expressed genes, we prepared a reference transcriptomic database through automatic assembly and annotation of the 758,510 redundant sequences (ESTs, mRNAs) of B. glabrata available in public databases. Computational analysis of Illumina reads followed by multivariate analyses allowed identification of 1685 candidate transcripts differentially expressed after an immune challenge, with a two fold ratio between transcripts showing a challenge-specific expression versus a lower or non-specific differential expression. Differential expression has been validated using quantitative PCR for a subset of randomly selected candidates. Predicted functions of annotated candidates (approx. 700 unisequences) belonged to a large extend to similar functional categories or protein types. This work significantly expands upon previous gene discovery and expression studies on B. glabrata and suggests that responses to various pathogens may involve similar immune processes or signaling pathways but different genes belonging to multigenic families. These results raise the question of the importance of gene duplication and acquisition of paralog functional diversity in the evolution of specific invertebrate immune responses. |
8. | Niehus, Sebastian; Giammarinaro, Philippe; Liégeois, Samuel; Quintin, Jessica; Ferrandon, Dominique Fly culture collapse disorder: detection, prophylaxis and eradication of the microsporidian parasite Tubulinosema ratisbonensis infecting Drosophila melanogaster Article de journal Fly (Austin), 6 (3), p. 193–204, 2012, ISSN: 1933-6942. Résumé | Liens | BibTeX | Étiquettes: Apansporoblastina, Apansporoblastina/*genetics/physiology, Base Sequence, cure, Disinfection, Disinfection/methods, DNA, DNA Primers, Drosophila melanogaster/*microbiology, fumagillin, Fungal, Fungal/chemistry, microsporidia, obligate intracellular parasitism, PCR detection, Phylogeny, Polymerase Chain Reaction, Polymerase Chain Reaction/methods, prophylaxis, Ribosomal, Ribosomal/chemistry, Sequence Alignment, Tubulinosema ratisbonensis @article{niehus_fly_2012b, title = {Fly culture collapse disorder: detection, prophylaxis and eradication of the microsporidian parasite Tubulinosema ratisbonensis infecting Drosophila melanogaster}, author = { Sebastian Niehus and Philippe Giammarinaro and Samuel Liégeois and Jessica Quintin and Dominique Ferrandon}, doi = {10.4161/fly.20896}, issn = {1933-6942}, year = {2012}, date = {2012-01-01}, journal = {Fly (Austin)}, volume = {6}, number = {3}, pages = {193--204}, abstract = {Drosophila melanogaster is a robust model to investigate many biological problems. It is however prone to some infections, which may endanger fly stocks if left unchecked for. One such infection is caused by an obligate fungal intracellular parasite, Tubulinosema ratisbonensis, which can be found in laboratory stocks. Here, we identify and briefly characterize a T. ratisbonensis strain that was infesting our Drosophila cultures and that required intensive measures to contain and eradicate the infection. We describe the phenotypes of infested stocks. We also report PCR-based techniques that allow the detection of infested stocks with a high sensitivity. We have developed a high-throughput qPCR assay that allows the efficient parallel screening of a large number of potentially-infested stocks. We also have investigated several prophylactic measures to prevent the further contamination of stocks, namely UV-exposure, ethanol treatment, bleaching, and desiccation. Bleaching was found to kill all spores. Other treatments were less effective but were found to be sufficient to prevent further contamination of noninfested stocks. Two treatments were efficacious in curing infested stocks (1) bleaching of eggs and subsequent raising of the larvae in clean vials; (2) fumagillin treatment. These cures only work on stocks that have not become too weak to withstand the procedures.}, keywords = {Apansporoblastina, Apansporoblastina/*genetics/physiology, Base Sequence, cure, Disinfection, Disinfection/methods, DNA, DNA Primers, Drosophila melanogaster/*microbiology, fumagillin, Fungal, Fungal/chemistry, microsporidia, obligate intracellular parasitism, PCR detection, Phylogeny, Polymerase Chain Reaction, Polymerase Chain Reaction/methods, prophylaxis, Ribosomal, Ribosomal/chemistry, Sequence Alignment, Tubulinosema ratisbonensis}, pubstate = {published}, tppubtype = {article} } Drosophila melanogaster is a robust model to investigate many biological problems. It is however prone to some infections, which may endanger fly stocks if left unchecked for. One such infection is caused by an obligate fungal intracellular parasite, Tubulinosema ratisbonensis, which can be found in laboratory stocks. Here, we identify and briefly characterize a T. ratisbonensis strain that was infesting our Drosophila cultures and that required intensive measures to contain and eradicate the infection. We describe the phenotypes of infested stocks. We also report PCR-based techniques that allow the detection of infested stocks with a high sensitivity. We have developed a high-throughput qPCR assay that allows the efficient parallel screening of a large number of potentially-infested stocks. We also have investigated several prophylactic measures to prevent the further contamination of stocks, namely UV-exposure, ethanol treatment, bleaching, and desiccation. Bleaching was found to kill all spores. Other treatments were less effective but were found to be sufficient to prevent further contamination of noninfested stocks. Two treatments were efficacious in curing infested stocks (1) bleaching of eggs and subsequent raising of the larvae in clean vials; (2) fumagillin treatment. These cures only work on stocks that have not become too weak to withstand the procedures. |
2011 |
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Articles de journaux |
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7. | Aoun, Richard Bou; Hetru, Charles; Troxler, Laurent; Doucet, Daniel; Ferrandon, Dominique; Matt, Nicolas Analysis of thioester-containing proteins during the innate immune response of Drosophila melanogaster Article de journal J Innate Immun, 3 (1), p. 52–64, 2011, ISSN: 1662-8128. Résumé | Liens | BibTeX | Étiquettes: bioinformatic, DNA, Evolution, Gene Expression Regulation, Hemocytes, Immunity, In Situ Hybridization, Innate, Molecular, Mutation, Phylogeny, Sequence Analysis @article{bou_aoun_analysis_2011, title = {Analysis of thioester-containing proteins during the innate immune response of Drosophila melanogaster}, author = { Richard Bou Aoun and Charles Hetru and Laurent Troxler and Daniel Doucet and Dominique Ferrandon and Nicolas Matt}, doi = {10.1159/000321554}, issn = {1662-8128}, year = {2011}, date = {2011-01-01}, journal = {J Innate Immun}, volume = {3}, number = {1}, pages = {52--64}, abstract = {Thioester-containing proteins (TEPs) are conserved proteins among insects that are thought to be involved in innate immunity. In Drosophila, the Tep family is composed of 6 genes named Tep1-Tep6. In this study, we investigated the phylogeny, expression pattern and roles of these genes in the host defense of Drosophila. Protostomian Tep genes are clustered in 3 distinct branches, 1 of which is specific to mosquitoes. Most D. melanogaster Tep genes are expressed in hemocytes, can be induced in the fat body, and are expressed in specific regions of the hypodermis. This expression pattern is consistent with a role in innate immunity. However, we find that TEP1, TEP2, and TEP4 are not strictly required in the body cavity to fight several bacterial and fungal infections. One possibility is that Drosophila TEPs act redundantly or that their absence can be compensated by other components of the immune response. TEPs may thus provide a subtle selective advantage during evolution. Alternatively, they may be required in host defense against specific as yet unidentified natural pathogens of Drosophila.}, keywords = {bioinformatic, DNA, Evolution, Gene Expression Regulation, Hemocytes, Immunity, In Situ Hybridization, Innate, Molecular, Mutation, Phylogeny, Sequence Analysis}, pubstate = {published}, tppubtype = {article} } Thioester-containing proteins (TEPs) are conserved proteins among insects that are thought to be involved in innate immunity. In Drosophila, the Tep family is composed of 6 genes named Tep1-Tep6. In this study, we investigated the phylogeny, expression pattern and roles of these genes in the host defense of Drosophila. Protostomian Tep genes are clustered in 3 distinct branches, 1 of which is specific to mosquitoes. Most D. melanogaster Tep genes are expressed in hemocytes, can be induced in the fat body, and are expressed in specific regions of the hypodermis. This expression pattern is consistent with a role in innate immunity. However, we find that TEP1, TEP2, and TEP4 are not strictly required in the body cavity to fight several bacterial and fungal infections. One possibility is that Drosophila TEPs act redundantly or that their absence can be compensated by other components of the immune response. TEPs may thus provide a subtle selective advantage during evolution. Alternatively, they may be required in host defense against specific as yet unidentified natural pathogens of Drosophila. |
2008 |
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Articles de journaux |
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6. | Deddouche, Safia; Matt, Nicolas ; Budd, Aidan ; Mueller, Stefanie ; Kemp, Cordula ; Galiana-Arnoux, Delphine ; Dostert, Catherine ; Antoniewski, Christophe ; Hoffmann, Jules A; Imler, Jean-Luc The DExD/Ħ-box helicase Dicer-2 mediates the induction of antiviral activity in drosophila Article de journal Nature Immunology, 9 (12), p. 1425–1432, 2008, ISSN: 1529-2916. Résumé | Liens | BibTeX | Étiquettes: Amino Acid, Electrophoresis, Fat Body, Gene Expression Regulation, Genetic, Genetically Modified, Humans, Phylogeny, Polyacrylamide Gel, Reverse Transcriptase Polymerase Chain Reaction, Ribonuclease III, RNA Helicases, Sequence Homology, Transcription, Virus Diseases @article{deddouche_dexd/h-box_2008, title = {The DExD/Ħ-box helicase Dicer-2 mediates the induction of antiviral activity in drosophila}, author = { Safia Deddouche and Nicolas Matt and Aidan Budd and Stefanie Mueller and Cordula Kemp and Delphine Galiana-Arnoux and Catherine Dostert and Christophe Antoniewski and Jules A. Hoffmann and Jean-Luc Imler}, doi = {10.1038/ni.1664}, issn = {1529-2916}, year = {2008}, date = {2008-12-01}, journal = {Nature Immunology}, volume = {9}, number = {12}, pages = {1425--1432}, abstract = {Drosophila, like other invertebrates and plants, relies mainly on RNA interference for its defense against viruses. In flies, viral infection also triggers the expression of many genes. One of the genes induced, Vago, encodes a 18-kilodalton cysteine-rich polypeptide. Here we provide genetic evidence that the Vago gene product controlled viral load in the fat body after infection with drosophila C virus. Induction of Vago was dependent on the helicase Dicer-2. Dicer-2 belongs to the same DExD/H-box helicase family as do the RIG-I-like receptors, which sense viral infection and mediate interferon induction in mammals. We propose that this family represents an evolutionary conserved set of sensors that detect viral nucleic acids and direct antiviral responses.}, keywords = {Amino Acid, Electrophoresis, Fat Body, Gene Expression Regulation, Genetic, Genetically Modified, Humans, Phylogeny, Polyacrylamide Gel, Reverse Transcriptase Polymerase Chain Reaction, Ribonuclease III, RNA Helicases, Sequence Homology, Transcription, Virus Diseases}, pubstate = {published}, tppubtype = {article} } Drosophila, like other invertebrates and plants, relies mainly on RNA interference for its defense against viruses. In flies, viral infection also triggers the expression of many genes. One of the genes induced, Vago, encodes a 18-kilodalton cysteine-rich polypeptide. Here we provide genetic evidence that the Vago gene product controlled viral load in the fat body after infection with drosophila C virus. Induction of Vago was dependent on the helicase Dicer-2. Dicer-2 belongs to the same DExD/H-box helicase family as do the RIG-I-like receptors, which sense viral infection and mediate interferon induction in mammals. We propose that this family represents an evolutionary conserved set of sensors that detect viral nucleic acids and direct antiviral responses. |
2007 |
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Articles de journaux |
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5. | Waterhouse, R M; Kriventseva, E V; Meister, Stephan; Xi, Z; Alvarez, K S; Bartholomay, L C; Barillas-Mury, Carolina; Bian, G; Blandin, Stéphanie A; Christensen, B M; Dong, Y; Jiang, H; Kanost, M R; Koutsos, A C; Levashina, Elena A; Li, J; Ligoxygakis, Petros; Maccallum, R M; Mayhew, G F; Mendes, A; Michel, K; Osta, M A; Paskewitz, S; Shin, S W; Vlachou, D; Wang, L; Wei, W; Zheng, L; Zou, Z; Severson, D W; Raikhel, A S; Kafatos, Fotis C; Dimopoulos, G; Zdobnov, E M; Christophides, G K Evolutionary dynamics of immune-related genes and pathways in disease-vector mosquitoes Article de journal Science, 316 , p. 5832, 2007. Résumé | Liens | BibTeX | Étiquettes: Evolution, Phylogeny @article{RM2007, title = {Evolutionary dynamics of immune-related genes and pathways in disease-vector mosquitoes}, author = {R. M. Waterhouse and E. V. Kriventseva and Stephan Meister and Z. Xi and K. S. Alvarez and L. C. Bartholomay and Carolina Barillas-Mury and G. Bian and Stéphanie A. Blandin and B. M. Christensen and Y. Dong and H. Jiang and M. R. Kanost and A. C. Koutsos and Elena A. Levashina and J. Li and Petros Ligoxygakis and R. M. Maccallum and G. F. Mayhew and A. Mendes and K. Michel and M. A. Osta and S. Paskewitz and S. W. Shin and D. Vlachou and L. Wang and W. Wei and L. Zheng and Z Zou and D. W. Severson and A. S. Raikhel and Fotis C. Kafatos and G. Dimopoulos and E. M. Zdobnov and G. K. Christophides}, url = {http://www.ncbi.nlm.nih.gov/pubmed/17588928}, year = {2007}, date = {2007-06-22}, journal = {Science}, volume = {316}, pages = {5832}, abstract = {Mosquitoes are vectors of parasitic and viral diseases of immense importance for public health. The acquisition of the genome sequence of the yellow fever and Dengue vector, Aedes aegypti (Aa), has enabled a comparative phylogenomic analysis of the insect immune repertoire: in Aa, the malaria vector Anopheles gambiae (Ag), and the fruit fly Drosophila melanogaster (Dm). Analysis of immune signaling pathways and response modules reveals both conservative and rapidly evolving features associated with different functional gene categories and particular aspects of immune reactions. These dynamics reflect in part continuous readjustment between accommodation and rejection of pathogens and suggest how innate immunity may have evolved.}, keywords = {Evolution, Phylogeny}, pubstate = {published}, tppubtype = {article} } Mosquitoes are vectors of parasitic and viral diseases of immense importance for public health. The acquisition of the genome sequence of the yellow fever and Dengue vector, Aedes aegypti (Aa), has enabled a comparative phylogenomic analysis of the insect immune repertoire: in Aa, the malaria vector Anopheles gambiae (Ag), and the fruit fly Drosophila melanogaster (Dm). Analysis of immune signaling pathways and response modules reveals both conservative and rapidly evolving features associated with different functional gene categories and particular aspects of immune reactions. These dynamics reflect in part continuous readjustment between accommodation and rejection of pathogens and suggest how innate immunity may have evolved. |
2004 |
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Articles de journaux |
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4. | Imler, Jean-Luc; Zheng, Liangbiao Biology of Toll receptors: lessons from insects and mammals Article de journal Journal of Leukocyte Biology, 75 (1), p. 18–26, 2004, ISSN: 0741-5400. Résumé | Liens | BibTeX | Étiquettes: Anopheles, Cell Surface, Humans, Membrane Glycoproteins, Mice, Phylogeny, Plant Physiological Phenomena, Receptors, Signal Transduction, Toll-Like Receptor 5, Toll-Like Receptors @article{imler_biology_2004, title = {Biology of Toll receptors: lessons from insects and mammals}, author = { Jean-Luc Imler and Liangbiao Zheng}, doi = {10.1189/jlb.0403160}, issn = {0741-5400}, year = {2004}, date = {2004-01-01}, journal = {Journal of Leukocyte Biology}, volume = {75}, number = {1}, pages = {18--26}, abstract = {Toll receptors are type I transmembrane proteins that play important roles in development and immunity in animals. Comparison of the genomes of mouse and human on one side and of the fruitfly Drosophila and the mosquito Anopheles (two dipteran insects) on the other, revealed that the four species possess a similar number of Toll receptors (approximately 10). However, phylogenetic analyses indicate that the families of Toll receptors expanded independently in insects and mammals. We review recent results on these receptors, which point to differences in the activation and signaling between Tolls in insects and Toll-like receptors (TLRs) in mammals. Whereas mammalian TLRs appear to be solely dedicated to host-defense, insect Tolls may be predominantly linked to other functions, probably developmental.}, keywords = {Anopheles, Cell Surface, Humans, Membrane Glycoproteins, Mice, Phylogeny, Plant Physiological Phenomena, Receptors, Signal Transduction, Toll-Like Receptor 5, Toll-Like Receptors}, pubstate = {published}, tppubtype = {article} } Toll receptors are type I transmembrane proteins that play important roles in development and immunity in animals. Comparison of the genomes of mouse and human on one side and of the fruitfly Drosophila and the mosquito Anopheles (two dipteran insects) on the other, revealed that the four species possess a similar number of Toll receptors (approximately 10). However, phylogenetic analyses indicate that the families of Toll receptors expanded independently in insects and mammals. We review recent results on these receptors, which point to differences in the activation and signaling between Tolls in insects and Toll-like receptors (TLRs) in mammals. Whereas mammalian TLRs appear to be solely dedicated to host-defense, insect Tolls may be predominantly linked to other functions, probably developmental. |
2002 |
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Articles de journaux |
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3. | Christophides, George K; Zdobnov, Evgeny; Barillas-Mury, Carolina; Birney, Ewan; Blandin, Stephanie A; Blass, Claudia; Brey, Paul T; Collins, Frank H; Danielli, Alberto; Dimopoulos, George; Hetru, Charles; Hoa, Ngo T; Hoffmann, Jules A; Kanzok, Stefan M; Letunic, Ivica; Levashina, Elena A; Loukeris, Thanasis G; Lycett, Gareth; Meister, Stephan; Michel, Kristin; Moita, Luis F; Müller, Hans-Michael; Osta, Mike A; Paskewitz, Susan M; Reichhart, Jean-Marc; Rzhetsky, Andrey; Troxler, Laurent; Vernick, Kenneth D; Vlachou, Dina; Volz, Jennifer; von Mering, Christian; Xu, Jiannong; Zheng, Liangbiao; Bork, Peer; Kafatos, Fotis C Immunity-related genes and gene families in Anopheles gambiae Article de journal Science, 298 (5591), p. 159–165, 2002, ISSN: 1095-9203. Résumé | Liens | BibTeX | Étiquettes: Alternative Splicing, Anopheles, Apoptosis, Bacteria, bioinformatic, Catechol Oxidase, Computational Biology, Enzyme Precursors, Gene Expression Regulation, Genes, Genetic, Genome, Immunity, Innate, Insect, Insect Proteins, Multigene Family, Peptides, Phylogeny, Plasmodium, Protein Structure, Selection, Serine Endopeptidases, Serpins, Signal Transduction, Tertiary @article{christophides_immunity-related_2002, title = {Immunity-related genes and gene families in Anopheles gambiae}, author = { George K. Christophides and Evgeny Zdobnov and Carolina Barillas-Mury and Ewan Birney and Stephanie A. Blandin and Claudia Blass and Paul T. Brey and Frank H. Collins and Alberto Danielli and George Dimopoulos and Charles Hetru and Ngo T. Hoa and Jules A. Hoffmann and Stefan M. Kanzok and Ivica Letunic and Elena A. Levashina and Thanasis G. Loukeris and Gareth Lycett and Stephan Meister and Kristin Michel and Luis F. Moita and Hans-Michael Müller and Mike A. Osta and Susan M. Paskewitz and Jean-Marc Reichhart and Andrey Rzhetsky and Laurent Troxler and Kenneth D. Vernick and Dina Vlachou and Jennifer Volz and Christian von Mering and Jiannong Xu and Liangbiao Zheng and Peer Bork and Fotis C. Kafatos}, url = {http://www.ncbi.nlm.nih.gov/pubmed/12364793}, doi = {10.1126/science.1077136}, issn = {1095-9203}, year = {2002}, date = {2002-10-01}, journal = {Science}, volume = {298}, number = {5591}, pages = {159--165}, abstract = {We have identified 242 Anopheles gambiae genes from 18 gene families implicated in innate immunity and have detected marked diversification relative to Drosophila melanogaster. Immune-related gene families involved in recognition, signal modulation, and effector systems show a marked deficit of orthologs and excessive gene expansions, possibly reflecting selection pressures from different pathogens encountered in these insects' very different life-styles. In contrast, the multifunctional Toll signal transduction pathway is substantially conserved, presumably because of counterselection for developmental stability. Representative expression profiles confirm that sequence diversification is accompanied by specific responses to different immune challenges. Alternative RNA splicing may also contribute to expansion of the immune repertoire.}, keywords = {Alternative Splicing, Anopheles, Apoptosis, Bacteria, bioinformatic, Catechol Oxidase, Computational Biology, Enzyme Precursors, Gene Expression Regulation, Genes, Genetic, Genome, Immunity, Innate, Insect, Insect Proteins, Multigene Family, Peptides, Phylogeny, Plasmodium, Protein Structure, Selection, Serine Endopeptidases, Serpins, Signal Transduction, Tertiary}, pubstate = {published}, tppubtype = {article} } We have identified 242 Anopheles gambiae genes from 18 gene families implicated in innate immunity and have detected marked diversification relative to Drosophila melanogaster. Immune-related gene families involved in recognition, signal modulation, and effector systems show a marked deficit of orthologs and excessive gene expansions, possibly reflecting selection pressures from different pathogens encountered in these insects' very different life-styles. In contrast, the multifunctional Toll signal transduction pathway is substantially conserved, presumably because of counterselection for developmental stability. Representative expression profiles confirm that sequence diversification is accompanied by specific responses to different immune challenges. Alternative RNA splicing may also contribute to expansion of the immune repertoire. |
1999 |
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Articles de journaux |
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2. | Hoffmann, Jules A; Kafatos, Fotis C; Janeway, Charles A; Ezekowitz, Alan R B Phylogenetic perspectives in innate immunity Article de journal Science, 284 (5418), p. 1313–1318, 1999, ISSN: 0036-8075. Résumé | BibTeX | Étiquettes: Active, Culicidae, Humans, Immunity, Immunological, Infection, Innate, Insect Vectors, Mammals, Models, Phagocytosis, Phylogeny, Proteins @article{hoffmann_phylogenetic_1999, title = {Phylogenetic perspectives in innate immunity}, author = { Jules A. Hoffmann and Fotis C. Kafatos and Charles A. Janeway and R. Alan B. Ezekowitz}, issn = {0036-8075}, year = {1999}, date = {1999-05-01}, journal = {Science}, volume = {284}, number = {5418}, pages = {1313--1318}, abstract = {The concept of innate immunity refers to the first-line host defense that serves to limit infection in the early hours after exposure to microorganisms. Recent data have highlighted similarities between pathogen recognition, signaling pathways, and effector mechanisms of innate immunity in Drosophila and mammals, pointing to a common ancestry of these defenses. In addition to its role in the early phase of defense, innate immunity in mammals appears to play a key role in stimulating the subsequent, clonal response of adaptive immunity.}, keywords = {Active, Culicidae, Humans, Immunity, Immunological, Infection, Innate, Insect Vectors, Mammals, Models, Phagocytosis, Phylogeny, Proteins}, pubstate = {published}, tppubtype = {article} } The concept of innate immunity refers to the first-line host defense that serves to limit infection in the early hours after exposure to microorganisms. Recent data have highlighted similarities between pathogen recognition, signaling pathways, and effector mechanisms of innate immunity in Drosophila and mammals, pointing to a common ancestry of these defenses. In addition to its role in the early phase of defense, innate immunity in mammals appears to play a key role in stimulating the subsequent, clonal response of adaptive immunity. |
1996 |
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Articles de journaux |
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1. | Charlet, Maurice; Chernysh, S; Philippe, H; Hetru, Charles; Hoffmann, Jules A; Bulet, Philippe Innate immunity. Isolation of several cysteine-rich antimicrobial peptides from the blood of a mollusc, Mytilus edulis Article de journal J. Biol. Chem., 271 (36), p. 21808–21813, 1996, ISSN: 0021-9258. Résumé | BibTeX | Étiquettes: Amino Acid, Anti-Infective Agents, Antifungal Agents, Bivalvia, Blood Proteins, Chromatography, Cysteine, Defensins, High Pressure Liquid, Molecular Weight, Phylogeny, Sequence Homology @article{charlet_innate_1996, title = {Innate immunity. Isolation of several cysteine-rich antimicrobial peptides from the blood of a mollusc, Mytilus edulis}, author = { Maurice Charlet and S. Chernysh and H. Philippe and Charles Hetru and Jules A. Hoffmann and Philippe Bulet}, issn = {0021-9258}, year = {1996}, date = {1996-09-01}, journal = {J. Biol. Chem.}, volume = {271}, number = {36}, pages = {21808--21813}, abstract = {We have isolated from the blood of immune-challenged and untreated mussels (Mytilus edulis) antibacterial and antifungal peptides. We have characterized two isoforms of a novel 34-residue, cysteine-rich, peptide with potent bactericidal activity and partially characterized a novel 6.2-kDa antifungal peptide containing 12 cysteines. We report the presence of two members of the insect defensin family of antibacterial peptides and provide a phylogenetic analysis that indicates that mollusc and arthropod defensins have a common ancestry. Our data argue that circulating antimicrobial peptides represent an ancient host defense mechanism that predated the separation between molluscs and arthropods at the root of the Cambrian, about 545 million years ago.}, keywords = {Amino Acid, Anti-Infective Agents, Antifungal Agents, Bivalvia, Blood Proteins, Chromatography, Cysteine, Defensins, High Pressure Liquid, Molecular Weight, Phylogeny, Sequence Homology}, pubstate = {published}, tppubtype = {article} } We have isolated from the blood of immune-challenged and untreated mussels (Mytilus edulis) antibacterial and antifungal peptides. We have characterized two isoforms of a novel 34-residue, cysteine-rich, peptide with potent bactericidal activity and partially characterized a novel 6.2-kDa antifungal peptide containing 12 cysteines. We report the presence of two members of the insect defensin family of antibacterial peptides and provide a phylogenetic analysis that indicates that mollusc and arthropod defensins have a common ancestry. Our data argue that circulating antimicrobial peptides represent an ancient host defense mechanism that predated the separation between molluscs and arthropods at the root of the Cambrian, about 545 million years ago. |
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