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Immunologie, Immunopathologie et Chimie Thérapeutique
Publications
2005
Kocks Christine, Cho Ju Hyun, Nehme Nadine, Ulvila Johanna, Pearson Alan M, Meister Marie, Strom Charles, Conto Stephanie L, Hetru Charles, Stuart Lynda M, Stehle Thilo, Hoffmann Jules A, Reichhart Jean-Marc, Ferrandon Dominique, Rämet Mika, Ezekowitz Alan R B
Eater, a transmembrane protein mediating phagocytosis of bacterial pathogens in Drosophila Article de journal
Dans: Cell, vol. 123, no. 2, p. 335–346, 2005, ISSN: 0092-8674.
Résumé | Liens | BibTeX | Étiquettes: Amino Acid, Amino Acid Motifs, Animals, Bacterial Infections, Cell Surface, Embryo, Escherichia coli, ferrandon, Flow Cytometry, Frameshift Mutation, Genes, Histidine, hoffmann, In Situ Hybridization, Insect, Insect Proteins, M3i, Macrophages, Membrane Proteins, messenger, Nonmammalian, Open Reading Frames, Phagocytosis, Receptors, reichhart, RNA, RNA Interference, Sequence Homology, Serratia marcescens
@article{kocks_eater_2005,
title = {Eater, a transmembrane protein mediating phagocytosis of bacterial pathogens in Drosophila},
author = {Christine Kocks and Ju Hyun Cho and Nadine Nehme and Johanna Ulvila and Alan M Pearson and Marie Meister and Charles Strom and Stephanie L Conto and Charles Hetru and Lynda M Stuart and Thilo Stehle and Jules A Hoffmann and Jean-Marc Reichhart and Dominique Ferrandon and Mika Rämet and Alan R B Ezekowitz},
doi = {10.1016/j.cell.2005.08.034},
issn = {0092-8674},
year = {2005},
date = {2005-10-01},
journal = {Cell},
volume = {123},
number = {2},
pages = {335--346},
abstract = {Phagocytosis is a complex, evolutionarily conserved process that plays a central role in host defense against infection. We have identified a predicted transmembrane protein, Eater, which is involved in phagocytosis in Drosophila. Transcriptional silencing of the eater gene in a macrophage cell line led to a significant reduction in the binding and internalization of bacteria. Moreover, the N terminus of the Eater protein mediated direct microbial binding which could be inhibited with scavenger receptor ligands, acetylated, and oxidized low-density lipoprotein. In vivo, eater expression was restricted to blood cells. Flies lacking the eater gene displayed normal responses in NF-kappaB-like Toll and IMD signaling pathways but showed impaired phagocytosis and decreased survival after bacterial infection. Our results suggest that Eater is a major phagocytic receptor for a broad range of bacterial pathogens in Drosophila and provide a powerful model to address the role of phagocytosis in vivo.},
keywords = {Amino Acid, Amino Acid Motifs, Animals, Bacterial Infections, Cell Surface, Embryo, Escherichia coli, ferrandon, Flow Cytometry, Frameshift Mutation, Genes, Histidine, hoffmann, In Situ Hybridization, Insect, Insect Proteins, M3i, Macrophages, Membrane Proteins, messenger, Nonmammalian, Open Reading Frames, Phagocytosis, Receptors, reichhart, RNA, RNA Interference, Sequence Homology, Serratia marcescens},
pubstate = {published},
tppubtype = {article}
}
Phagocytosis is a complex, evolutionarily conserved process that plays a central role in host defense against infection. We have identified a predicted transmembrane protein, Eater, which is involved in phagocytosis in Drosophila. Transcriptional silencing of the eater gene in a macrophage cell line led to a significant reduction in the binding and internalization of bacteria. Moreover, the N terminus of the Eater protein mediated direct microbial binding which could be inhibited with scavenger receptor ligands, acetylated, and oxidized low-density lipoprotein. In vivo, eater expression was restricted to blood cells. Flies lacking the eater gene displayed normal responses in NF-kappaB-like Toll and IMD signaling pathways but showed impaired phagocytosis and decreased survival after bacterial infection. Our results suggest that Eater is a major phagocytic receptor for a broad range of bacterial pathogens in Drosophila and provide a powerful model to address the role of phagocytosis in vivo.
Imler Jean-Luc, Bulet Philippe
Antimicrobial peptides in Drosophila: structures, activities and gene regulation Article de journal
Dans: Chemical Immunology and Allergy, vol. 86, p. 1–21, 2005, ISSN: 1660-2242.
Résumé | Liens | BibTeX | Étiquettes: Animals, Antimicrobial Cationic Peptides, Defensins, Gene Expression Regulation, Genes, Glycopeptides, imler, Immunity, Innate, Insect, Insect Proteins, M3i, Molecular Structure, Signal Transduction
@article{imler_antimicrobial_2005,
title = {Antimicrobial peptides in Drosophila: structures, activities and gene regulation},
author = {Jean-Luc Imler and Philippe Bulet},
doi = {10.1159/000086648},
issn = {1660-2242},
year = {2005},
date = {2005-01-01},
journal = {Chemical Immunology and Allergy},
volume = {86},
pages = {1--21},
abstract = {The production of antimicrobial peptides (AMPs) is an important aspect of host-defence in multicellular organisms. Biochemical analysis of the hemolymph of the fruit-fly Drosophila melanogaster and other Diptera has led to the discovery of eight classes of AMPs. These peptides can be grouped into three families based on their main biological targets, gram-positive bacteria (defensin), gram-negative bacteria (cecropins, drosocin, attacins, diptericin, MPAC), or fungi (drosomycin, metchnikowin). Drosophila AMPs are synthesized by the fat body in response to infection, and secreted into the blood. Most of them can also be induced in surface epithelia in a tissue-specific manner. Finally, some of them are constitutively expressed in defined tissues, such as the salivary glands or the reproductive tract. We review here the structures and activities of these AMPs, as well as the signalling cascades, which lead to their induction upon detection of infectious non-self.},
keywords = {Animals, Antimicrobial Cationic Peptides, Defensins, Gene Expression Regulation, Genes, Glycopeptides, imler, Immunity, Innate, Insect, Insect Proteins, M3i, Molecular Structure, Signal Transduction},
pubstate = {published},
tppubtype = {article}
}
The production of antimicrobial peptides (AMPs) is an important aspect of host-defence in multicellular organisms. Biochemical analysis of the hemolymph of the fruit-fly Drosophila melanogaster and other Diptera has led to the discovery of eight classes of AMPs. These peptides can be grouped into three families based on their main biological targets, gram-positive bacteria (defensin), gram-negative bacteria (cecropins, drosocin, attacins, diptericin, MPAC), or fungi (drosomycin, metchnikowin). Drosophila AMPs are synthesized by the fat body in response to infection, and secreted into the blood. Most of them can also be induced in surface epithelia in a tissue-specific manner. Finally, some of them are constitutively expressed in defined tissues, such as the salivary glands or the reproductive tract. We review here the structures and activities of these AMPs, as well as the signalling cascades, which lead to their induction upon detection of infectious non-self.
2004
Blandin Stephanie A, Shiao Shin-Hong, Moita Luis F, Janse Chris J, Waters Andrew P, Kafatos Fotis C, Levashina Elena A
Complement-like protein TEP1 is a determinant of vectorial capacity in the malaria vector Anopheles gambiae Article de journal
Dans: Cell, vol. 116, no. 5, p. 661–670, 2004, ISSN: 0092-8674.
Résumé | BibTeX | Étiquettes: Animals, Anopheles, blandin, Female, Genetic, Humans, Insect Proteins, Insect Vectors, M3i, Malaria, Models, Molecular, Plasmodium berghei, Polymorphism, Protein Structure, RNA, Sequence Alignment, Tertiary
@article{blandin_complement-like_2004,
title = {Complement-like protein TEP1 is a determinant of vectorial capacity in the malaria vector Anopheles gambiae},
author = {Stephanie A Blandin and Shin-Hong Shiao and Luis F Moita and Chris J Janse and Andrew P Waters and Fotis C Kafatos and Elena A Levashina},
issn = {0092-8674},
year = {2004},
date = {2004-01-01},
journal = {Cell},
volume = {116},
number = {5},
pages = {661--670},
abstract = {Anopheles mosquitoes are major vectors of human malaria in Africa. Large variation exists in the ability of mosquitoes to serve as vectors and to transmit malaria parasites, but the molecular mechanisms that determine vectorial capacity remain poorly understood. We report that the hemocyte-specific complement-like protein TEP1 from the mosquito Anopheles gambiae binds to and mediates killing of midgut stages of the rodent malaria parasite Plasmodium berghei. The dsRNA knockdown of TEP1 in adults completely abolishes melanotic refractoriness in a genetically selected refractory strain. Moreover, in susceptible mosquitoes this knockdown increases the number of developing parasites. Our results suggest that the TEP1-dependent parasite killing is followed by a TEP1-independent clearance of dead parasites by lysis and/or melanization. Further elucidation of the molecular mechanisms of TEP1-mediated parasite killing will be of great importance for our understanding of the principles of vectorial capacity in insects.},
keywords = {Animals, Anopheles, blandin, Female, Genetic, Humans, Insect Proteins, Insect Vectors, M3i, Malaria, Models, Molecular, Plasmodium berghei, Polymorphism, Protein Structure, RNA, Sequence Alignment, Tertiary},
pubstate = {published},
tppubtype = {article}
}
Anopheles mosquitoes are major vectors of human malaria in Africa. Large variation exists in the ability of mosquitoes to serve as vectors and to transmit malaria parasites, but the molecular mechanisms that determine vectorial capacity remain poorly understood. We report that the hemocyte-specific complement-like protein TEP1 from the mosquito Anopheles gambiae binds to and mediates killing of midgut stages of the rodent malaria parasite Plasmodium berghei. The dsRNA knockdown of TEP1 in adults completely abolishes melanotic refractoriness in a genetically selected refractory strain. Moreover, in susceptible mosquitoes this knockdown increases the number of developing parasites. Our results suggest that the TEP1-dependent parasite killing is followed by a TEP1-independent clearance of dead parasites by lysis and/or melanization. Further elucidation of the molecular mechanisms of TEP1-mediated parasite killing will be of great importance for our understanding of the principles of vectorial capacity in insects.
Imler Jean-Luc, Ferrandon Dominique, Royet Julien, Reichhart Jean-Marc, Hetru Charles, Hoffmann Jules A
Toll-dependent and Toll-independent immune responses in Drosophila Article de journal
Dans: Journal of Endotoxin Research, vol. 10, no. 4, p. 241–246, 2004, ISSN: 0968-0519.
Résumé | Liens | BibTeX | Étiquettes: Acute-Phase Proteins, Animals, Blood Proteins, Cell Surface, ferrandon, hoffmann, imler, Insect Proteins, M3i, Membrane Glycoproteins, Receptors, reichhart, Toll-Like Receptor 5, Toll-Like Receptors, Up-Regulation
@article{imler_toll-dependent_2004,
title = {Toll-dependent and Toll-independent immune responses in Drosophila},
author = {Jean-Luc Imler and Dominique Ferrandon and Julien Royet and Jean-Marc Reichhart and Charles Hetru and Jules A Hoffmann},
doi = {10.1179/096805104225005887},
issn = {0968-0519},
year = {2004},
date = {2004-01-01},
journal = {Journal of Endotoxin Research},
volume = {10},
number = {4},
pages = {241--246},
abstract = {The multifaceted response of the fruitfly Drosophila melanogaster to infection by a wide range of microbes is complex and remarkably efficient. Its most prominent aspect is the immune-inducible expression of a set of potent antimicrobial peptides. Genetic analysis of the regulation of the genes encoding these peptides has led to the identification of the receptor Toll as an essential component of the fly's host defense system. In addition, these studies have revealed that the response to Gram-negative bacterial infections involves Toll-independent mechanisms, and that the sensing of infection involves two structurally distinct sets of molecules--the PGRPs and the GNBPs/betaGRPs.},
keywords = {Acute-Phase Proteins, Animals, Blood Proteins, Cell Surface, ferrandon, hoffmann, imler, Insect Proteins, M3i, Membrane Glycoproteins, Receptors, reichhart, Toll-Like Receptor 5, Toll-Like Receptors, Up-Regulation},
pubstate = {published},
tppubtype = {article}
}
The multifaceted response of the fruitfly Drosophila melanogaster to infection by a wide range of microbes is complex and remarkably efficient. Its most prominent aspect is the immune-inducible expression of a set of potent antimicrobial peptides. Genetic analysis of the regulation of the genes encoding these peptides has led to the identification of the receptor Toll as an essential component of the fly's host defense system. In addition, these studies have revealed that the response to Gram-negative bacterial infections involves Toll-independent mechanisms, and that the sensing of infection involves two structurally distinct sets of molecules--the PGRPs and the GNBPs/betaGRPs.
2003
Gobert Vanessa, Gottar Marie, Matskevich Alexey A, Rutschmann Sophie, Royet Julien, Belvin Marcia, Hoffmann Jules A, Ferrandon Dominique
Dual activation of the Drosophila toll pathway by two pattern recognition receptors Article de journal
Dans: Science, vol. 302, no. 5653, p. 2126–2130, 2003, ISSN: 1095-9203.
Résumé | Liens | BibTeX | Étiquettes: Animals, Carrier Proteins, Cell Surface, DNA Transposable Elements, ferrandon, Gene Expression, Genes, Gram-Negative Bacteria, Gram-Positive Bacteria, Hemolymph, hoffmann, Hypocreales, Insect, Insect Proteins, M3i, Mutation, Phenotype, Receptors, Serine Endopeptidases, Toll-Like Receptors
@article{gobert_dual_2003,
title = {Dual activation of the Drosophila toll pathway by two pattern recognition receptors},
author = {Vanessa Gobert and Marie Gottar and Alexey A Matskevich and Sophie Rutschmann and Julien Royet and Marcia Belvin and Jules A Hoffmann and Dominique Ferrandon},
doi = {10.1126/science.1085432},
issn = {1095-9203},
year = {2003},
date = {2003-12-01},
journal = {Science},
volume = {302},
number = {5653},
pages = {2126--2130},
abstract = {The Toll-dependent defense against Gram-positive bacterial infections in Drosophila is mediated through the peptidoglycan recognition protein SA (PGRP-SA). A mutation termed osiris disrupts the Gram-negative binding protein 1 (GNBP1) gene and leads to compromised survival of mutant flies after Gram-positive infections, but not after fungal or Gram-negative bacterial challenge. Our results demonstrate that GNBP1 and PGRP-SA can jointly activate the Toll pathway. The potential for a combination of distinct proteins to mediate detection of infectious nonself in the fly will refine the concept of pattern recognition in insects.},
keywords = {Animals, Carrier Proteins, Cell Surface, DNA Transposable Elements, ferrandon, Gene Expression, Genes, Gram-Negative Bacteria, Gram-Positive Bacteria, Hemolymph, hoffmann, Hypocreales, Insect, Insect Proteins, M3i, Mutation, Phenotype, Receptors, Serine Endopeptidases, Toll-Like Receptors},
pubstate = {published},
tppubtype = {article}
}
The Toll-dependent defense against Gram-positive bacterial infections in Drosophila is mediated through the peptidoglycan recognition protein SA (PGRP-SA). A mutation termed osiris disrupts the Gram-negative binding protein 1 (GNBP1) gene and leads to compromised survival of mutant flies after Gram-positive infections, but not after fungal or Gram-negative bacterial challenge. Our results demonstrate that GNBP1 and PGRP-SA can jointly activate the Toll pathway. The potential for a combination of distinct proteins to mediate detection of infectious nonself in the fly will refine the concept of pattern recognition in insects.
Weber Alexander N R, Tauszig-Delamasure Servane, Hoffmann Jules A, Lelièvre Eric, Gascan Hugues, Ray Keith P, Morse Mary A, Imler Jean-Luc, Gay Nicholas J
Binding of the Drosophila cytokine Spätzle to Toll is direct and establishes signaling Article de journal
Dans: Nature Immunology, vol. 4, no. 8, p. 794–800, 2003, ISSN: 1529-2908.
Résumé | Liens | BibTeX | Étiquettes: Animals, Cell Surface, hoffmann, imler, Insect Proteins, M3i, Protein Binding, Protein Structure, Receptors, Signal Transduction, Tertiary, Toll-Like Receptors
@article{weber_binding_2003,
title = {Binding of the Drosophila cytokine Spätzle to Toll is direct and establishes signaling},
author = {Alexander N R Weber and Servane Tauszig-Delamasure and Jules A Hoffmann and Eric Lelièvre and Hugues Gascan and Keith P Ray and Mary A Morse and Jean-Luc Imler and Nicholas J Gay},
doi = {10.1038/ni955},
issn = {1529-2908},
year = {2003},
date = {2003-08-01},
journal = {Nature Immunology},
volume = {4},
number = {8},
pages = {794--800},
abstract = {The extracellular protein Spätzle is required for activation of the Toll signaling pathway in the embryonic development and innate immune defense of Drosophila. Spätzle is synthesized as a pro-protein and is processed to a functional form by a serine protease. We show here that the mature form of Spätzle triggers a Toll-dependent immune response after injection into the hemolymph of flies. Spätzle specifically bound to Drosophila cells and to Cos-7 cells expressing Toll. Furthermore, in vitro experiments showed that the mature form of Spätzle bound to the Toll ectodomain with high affinity and with a stoichiometry of one Spätzle dimer to two receptors. The Spätzle pro-protein was inactive in all these assays, indicating that the pro-domain sequence, which is natively unstructured, acts to prevent interaction of the cytokine and its receptor Toll. These results show that, in contrast to the human Toll-like receptors, Drosophila Toll requires only an endogenous protein ligand for activation and signaling.},
keywords = {Animals, Cell Surface, hoffmann, imler, Insect Proteins, M3i, Protein Binding, Protein Structure, Receptors, Signal Transduction, Tertiary, Toll-Like Receptors},
pubstate = {published},
tppubtype = {article}
}
The extracellular protein Spätzle is required for activation of the Toll signaling pathway in the embryonic development and innate immune defense of Drosophila. Spätzle is synthesized as a pro-protein and is processed to a functional form by a serine protease. We show here that the mature form of Spätzle triggers a Toll-dependent immune response after injection into the hemolymph of flies. Spätzle specifically bound to Drosophila cells and to Cos-7 cells expressing Toll. Furthermore, in vitro experiments showed that the mature form of Spätzle bound to the Toll ectodomain with high affinity and with a stoichiometry of one Spätzle dimer to two receptors. The Spätzle pro-protein was inactive in all these assays, indicating that the pro-domain sequence, which is natively unstructured, acts to prevent interaction of the cytokine and its receptor Toll. These results show that, in contrast to the human Toll-like receptors, Drosophila Toll requires only an endogenous protein ligand for activation and signaling.
Luna C, Hoa N T, Zhang J, Kanzok S M, Brown S E, Imler Jean-Luc, Knudson D L, Zheng L
Characterization of three Toll-like genes from mosquito Aedes aegypti Article de journal
Dans: Insect Molecular Biology, vol. 12, no. 1, p. 67–74, 2003, ISSN: 0962-1075.
Résumé | BibTeX | Étiquettes: Aedes, Animals, Base Sequence, Cell Surface, Chimera, Cloning, Developmental, Female, Gene Expression Regulation, Genetic, imler, Insect Proteins, M3i, Male, messenger, Models, Molecular, Mutagenesis, Promoter Regions, Receptors, Reverse Transcriptase Polymerase Chain Reaction, RNA, Sequence Alignment, Signal Transduction, Site-Directed, Transfection
@article{luna_characterization_2003,
title = {Characterization of three Toll-like genes from mosquito Aedes aegypti},
author = {C Luna and N T Hoa and J Zhang and S M Kanzok and S E Brown and Jean-Luc Imler and D L Knudson and L Zheng},
issn = {0962-1075},
year = {2003},
date = {2003-02-01},
journal = {Insect Molecular Biology},
volume = {12},
number = {1},
pages = {67--74},
abstract = {Three Toll-related genes (AeToll1A, AeToll1B and AeToll5) were cloned and characterized from the yellow fever vector mosquito, Aedes aegypti. All three genes exhibited high levels of amino acid sequence similarity with Drosophila melanogaster (Dm)Toll1 and DmTehao (Toll5). AeToll1A and AeToll1B are 1124 and 1076 amino acid residues long, respectively. Both contain a carboxyl extension downstream of the Toll/interleukin-1 receptor (TIR) domain. AeToll5 is 1007 residues long and, like DmTehao, lacks the carboxyl terminal extension. Expression of these three genes was examined throughout development and after immune challenge. Both AeToll1A and AeToll5, like their Drosophila counterparts, activate transcription of drosomycin promoter in both Aedes and Drosophila cell lines. Deletion of the carboxyl extension of AeToll1A did not result in a further elevated level of the antifungal response. The intracellular signalling process appears to be species specific based on two observations. (1) DmToll is completely inactive in an Aedes cell line, suggesting a higher specificity requirement for DmToll in the intracellular signalling process. (2) Only one of three amino acid residues essential for DmToll function is required for AeToll1A function.},
keywords = {Aedes, Animals, Base Sequence, Cell Surface, Chimera, Cloning, Developmental, Female, Gene Expression Regulation, Genetic, imler, Insect Proteins, M3i, Male, messenger, Models, Molecular, Mutagenesis, Promoter Regions, Receptors, Reverse Transcriptase Polymerase Chain Reaction, RNA, Sequence Alignment, Signal Transduction, Site-Directed, Transfection},
pubstate = {published},
tppubtype = {article}
}
Three Toll-related genes (AeToll1A, AeToll1B and AeToll5) were cloned and characterized from the yellow fever vector mosquito, Aedes aegypti. All three genes exhibited high levels of amino acid sequence similarity with Drosophila melanogaster (Dm)Toll1 and DmTehao (Toll5). AeToll1A and AeToll1B are 1124 and 1076 amino acid residues long, respectively. Both contain a carboxyl extension downstream of the Toll/interleukin-1 receptor (TIR) domain. AeToll5 is 1007 residues long and, like DmTehao, lacks the carboxyl terminal extension. Expression of these three genes was examined throughout development and after immune challenge. Both AeToll1A and AeToll5, like their Drosophila counterparts, activate transcription of drosomycin promoter in both Aedes and Drosophila cell lines. Deletion of the carboxyl extension of AeToll1A did not result in a further elevated level of the antifungal response. The intracellular signalling process appears to be species specific based on two observations. (1) DmToll is completely inactive in an Aedes cell line, suggesting a higher specificity requirement for DmToll in the intracellular signalling process. (2) Only one of three amino acid residues essential for DmToll function is required for AeToll1A function.
2002
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
Dans: Science, vol. 298, no. 5591, p. 159–165, 2002, ISSN: 1095-9203.
Résumé | Liens | BibTeX | Étiquettes: Alternative Splicing, Animals, Anopheles, Apoptosis, bacteria, bioinformatic, blandin, Catechol Oxidase, Computational Biology, Enzyme Precursors, Gene Expression Regulation, Genes, Genetic, Genome, hoffmann, Immunity, Innate, Insect, Insect Proteins, M3i, Multigene Family, Peptides, Phylogeny, Plasmodium, Protein Structure, reichhart, 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, Animals, Anopheles, Apoptosis, bacteria, bioinformatic, blandin, Catechol Oxidase, Computational Biology, Enzyme Precursors, Gene Expression Regulation, Genes, Genetic, Genome, hoffmann, Immunity, Innate, Insect, Insect Proteins, M3i, Multigene Family, Peptides, Phylogeny, Plasmodium, Protein Structure, reichhart, 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.
Ligoxygakis Petros, Pelte Nadège, Hoffmann Jules A, Reichhart Jean-Marc
Activation of Drosophila Toll during fungal infection by a blood serine protease Article de journal
Dans: Science, vol. 297, no. 5578, p. 114–116, 2002, ISSN: 1095-9203.
Résumé | Liens | BibTeX | Étiquettes: Animals, Cell Surface, Chromosome Mapping, Escherichia coli, Female, Gene Expression Regulation, Genes, Gram-Positive Cocci, Hemolymph, hoffmann, Hypocreales, Insect, Insect Proteins, M3i, Male, Mutation, Protein Sorting Signals, Protein Structure, Receptors, reichhart, Serine Endopeptidases, Tertiary, Toll-Like Receptors
@article{ligoxygakis_activation_2002,
title = {Activation of Drosophila Toll during fungal infection by a blood serine protease},
author = {Petros Ligoxygakis and Nadège Pelte and Jules A Hoffmann and Jean-Marc Reichhart},
doi = {10.1126/science.1072391},
issn = {1095-9203},
year = {2002},
date = {2002-07-01},
journal = {Science},
volume = {297},
number = {5578},
pages = {114--116},
abstract = {Drosophila host defense to fungal and Gram-positive bacterial infection is mediated by the Spaetzle/Toll/cactus gene cassette. It has been proposed that Toll does not function as a pattern recognition receptor per se but is activated through a cleaved form of the cytokine Spaetzle. The upstream events linking infection to the cleavage of Spaetzle have long remained elusive. Here we report the identification of a central component of the fungal activation of Toll. We show that ethylmethane sulfonate-induced mutations in the persephone gene, which encodes a previously unknown serine protease, block induction of the Toll pathway by fungi and resistance to this type of infection.},
keywords = {Animals, Cell Surface, Chromosome Mapping, Escherichia coli, Female, Gene Expression Regulation, Genes, Gram-Positive Cocci, Hemolymph, hoffmann, Hypocreales, Insect, Insect Proteins, M3i, Male, Mutation, Protein Sorting Signals, Protein Structure, Receptors, reichhart, Serine Endopeptidases, Tertiary, Toll-Like Receptors},
pubstate = {published},
tppubtype = {article}
}
Drosophila host defense to fungal and Gram-positive bacterial infection is mediated by the Spaetzle/Toll/cactus gene cassette. It has been proposed that Toll does not function as a pattern recognition receptor per se but is activated through a cleaved form of the cytokine Spaetzle. The upstream events linking infection to the cleavage of Spaetzle have long remained elusive. Here we report the identification of a central component of the fungal activation of Toll. We show that ethylmethane sulfonate-induced mutations in the persephone gene, which encodes a previously unknown serine protease, block induction of the Toll pathway by fungi and resistance to this type of infection.
Ligoxygakis Petros, Bulet Philippe, Reichhart Jean-Marc
Critical evaluation of the role of the Toll-like receptor 18-Wheeler in the host defense of Drosophila Article de journal
Dans: EMBO Rep., vol. 3, no. 7, p. 666–673, 2002, ISSN: 1469-221X.
Résumé | Liens | BibTeX | Étiquettes: Animals, Anti-Bacterial Agents, Antimicrobial Cationic Peptides, Cell Adhesion Molecules, Fat Body, Gene Expression Regulation, Genes, Immunohistochemistry, Immunologic, Insect, Insect Proteins, Larva, M3i, Mass, Matrix-Assisted Laser Desorption-Ionization, Membrane Proteins, Receptors, reichhart, Reporter, Spectrometry, Transgenes
@article{ligoxygakis_critical_2002,
title = {Critical evaluation of the role of the Toll-like receptor 18-Wheeler in the host defense of Drosophila},
author = {Petros Ligoxygakis and Philippe Bulet and Jean-Marc Reichhart},
doi = {10.1093/embo-reports/kvf130},
issn = {1469-221X},
year = {2002},
date = {2002-01-01},
journal = {EMBO Rep.},
volume = {3},
number = {7},
pages = {666--673},
abstract = {Essential aspects of innate immune responses to microbial infections appear to be conserved between insects and mammals. In particular, in both groups, transmembrane receptors of the Toll superfamily play a crucial role in activating immune defenses. The Drosophila Toll family member 18-Wheeler had been proposed to sense Gram-negative infection and direct selective expression of peptides active against Gram-negative bacteria. Here we re-examine the role of 18-Wheeler and show that in adults it is dispensable for immune responses. In larvae, 18wheeler is required for normal fat body development, and in mutant larvae induction of all antimicrobial peptide genes, and not only of those directed against Gram-negative bacteria, is compromised. 18-Wheeler does not qualify as a pattern recognition receptor of Gram-negative bacteria.},
keywords = {Animals, Anti-Bacterial Agents, Antimicrobial Cationic Peptides, Cell Adhesion Molecules, Fat Body, Gene Expression Regulation, Genes, Immunohistochemistry, Immunologic, Insect, Insect Proteins, Larva, M3i, Mass, Matrix-Assisted Laser Desorption-Ionization, Membrane Proteins, Receptors, reichhart, Reporter, Spectrometry, Transgenes},
pubstate = {published},
tppubtype = {article}
}
Essential aspects of innate immune responses to microbial infections appear to be conserved between insects and mammals. In particular, in both groups, transmembrane receptors of the Toll superfamily play a crucial role in activating immune defenses. The Drosophila Toll family member 18-Wheeler had been proposed to sense Gram-negative infection and direct selective expression of peptides active against Gram-negative bacteria. Here we re-examine the role of 18-Wheeler and show that in adults it is dispensable for immune responses. In larvae, 18wheeler is required for normal fat body development, and in mutant larvae induction of all antimicrobial peptide genes, and not only of those directed against Gram-negative bacteria, is compromised. 18-Wheeler does not qualify as a pattern recognition receptor of Gram-negative bacteria.
Tauszig-Delamasure Servane, Bilak Hana, Capovilla Maria, Hoffmann Jules A, Imler Jean-Luc
Drosophila MyD88 is required for the response to fungal and Gram-positive bacterial infections Article de journal
Dans: Nature Immunology, vol. 3, no. 1, p. 91–97, 2002, ISSN: 1529-2908.
Résumé | Liens | BibTeX | Étiquettes: Adaptor Proteins, Amino Acid, Animals, Antigens, Antimicrobial Cationic Peptides, Cell Surface, Chromosome Mapping, Differentiation, Disease Susceptibility, Enterococcus faecalis, Epistasis, Escherichia coli, Female, Gene Expression Regulation, Genes, Genetic, Genetically Modified, Gram-Negative Bacteria, hoffmann, Hypocreales, imler, Immunologic, Insect, Insect Proteins, M3i, Membrane Glycoproteins, Micrococcus luteus, Myeloid Differentiation Factor 88, Protein Structure, Protein-Serine-Threonine Kinases, Receptors, Recombinant Fusion Proteins, Sequence Alignment, Sequence Homology, Signal Transducing, Tertiary, Toll-Like Receptors, Transfection
@article{tauszig-delamasure_drosophila_2002,
title = {Drosophila MyD88 is required for the response to fungal and Gram-positive bacterial infections},
author = {Servane Tauszig-Delamasure and Hana Bilak and Maria Capovilla and Jules A Hoffmann and Jean-Luc Imler},
doi = {10.1038/ni747},
issn = {1529-2908},
year = {2002},
date = {2002-01-01},
journal = {Nature Immunology},
volume = {3},
number = {1},
pages = {91--97},
abstract = {We report here the identification and functional characterization of DmMyD88, a gene encoding the Drosophila homolog of mammalian MyD88. DmMyD88 combines a Toll-IL-1R homology (TIR) domain and a death domain. Overexpression of DmMyD88 was sufficient to induce expression of the antifungal peptide Drosomycin, and induction of Drosomycin was markedly reduced in DmMyD88-mutant flies. DmMyD88 interacted with Toll through its TIR domain and required the death domain proteins Tube and Pelle to activate expression of Drs, which encodes Drosomycin. DmMyD88-mutant flies were highly susceptible to infection by fungi and Gram-positive bacteria, but resisted Gram-negative bacterial infection much as did wild-type flies. Phenotypic comparison of DmMyD88-mutant flies and MyD88-deficient mice showed essential differences in the control of Gram-negative infection in insects and mammals.},
keywords = {Adaptor Proteins, Amino Acid, Animals, Antigens, Antimicrobial Cationic Peptides, Cell Surface, Chromosome Mapping, Differentiation, Disease Susceptibility, Enterococcus faecalis, Epistasis, Escherichia coli, Female, Gene Expression Regulation, Genes, Genetic, Genetically Modified, Gram-Negative Bacteria, hoffmann, Hypocreales, imler, Immunologic, Insect, Insect Proteins, M3i, Membrane Glycoproteins, Micrococcus luteus, Myeloid Differentiation Factor 88, Protein Structure, Protein-Serine-Threonine Kinases, Receptors, Recombinant Fusion Proteins, Sequence Alignment, Sequence Homology, Signal Transducing, Tertiary, Toll-Like Receptors, Transfection},
pubstate = {published},
tppubtype = {article}
}
We report here the identification and functional characterization of DmMyD88, a gene encoding the Drosophila homolog of mammalian MyD88. DmMyD88 combines a Toll-IL-1R homology (TIR) domain and a death domain. Overexpression of DmMyD88 was sufficient to induce expression of the antifungal peptide Drosomycin, and induction of Drosomycin was markedly reduced in DmMyD88-mutant flies. DmMyD88 interacted with Toll through its TIR domain and required the death domain proteins Tube and Pelle to activate expression of Drs, which encodes Drosomycin. DmMyD88-mutant flies were highly susceptible to infection by fungi and Gram-positive bacteria, but resisted Gram-negative bacterial infection much as did wild-type flies. Phenotypic comparison of DmMyD88-mutant flies and MyD88-deficient mice showed essential differences in the control of Gram-negative infection in insects and mammals.
2001
Michel T, Reichhart Jean-Marc, Hoffmann Jules A, Royet Julien
Drosophila Toll is activated by Gram-positive bacteria through a circulating peptidoglycan recognition protein Article de journal
Dans: Nature, vol. 414, no. 6865, p. 756–759, 2001, ISSN: 0028-0836.
Résumé | Liens | BibTeX | Étiquettes: Amino Acid, Animals, Anti-Bacterial Agents, Anti-Infective Agents, Bacillus thuringiensis, Carrier Proteins, Cell Surface, Chromosome Mapping, Enterococcus faecalis, Fungi, Genes, Gram-Positive Bacteria, Hemolymph, hoffmann, Humans, Insect, Insect Proteins, M3i, Membrane Glycoproteins, Micrococcus luteus, Mutation, Receptors, reichhart, Sequence Homology, Toll-Like Receptors
@article{michel_drosophila_2001,
title = {Drosophila Toll is activated by Gram-positive bacteria through a circulating peptidoglycan recognition protein},
author = {T Michel and Jean-Marc Reichhart and Jules A Hoffmann and Julien Royet},
doi = {10.1038/414756a},
issn = {0028-0836},
year = {2001},
date = {2001-12-01},
journal = {Nature},
volume = {414},
number = {6865},
pages = {756--759},
abstract = {Microbial infection activates two distinct intracellular signalling cascades in the immune-responsive fat body of Drosophila. Gram-positive bacteria and fungi predominantly induce the Toll signalling pathway, whereas Gram-negative bacteria activate the Imd pathway. Loss-of-function mutants in either pathway reduce the resistance to corresponding infections. Genetic screens have identified a range of genes involved in these intracellular signalling cascades, but how they are activated by microbial infection is largely unknown. Activation of the transmembrane receptor Toll requires a proteolytically cleaved form of an extracellular cytokine-like polypeptide, Spätzle, suggesting that Toll does not itself function as a bona fide recognition receptor of microbial patterns. This is in apparent contrast with the mammalian Toll-like receptors and raises the question of which host molecules actually recognize microbial patterns to activate Toll through Spätzle. Here we present a mutation that blocks Toll activation by Gram-positive bacteria and significantly decreases resistance to this type of infection. The mutation semmelweis (seml) inactivates the gene encoding a peptidoglycan recognition protein (PGRP-SA). Interestingly, seml does not affect Toll activation by fungal infection, indicating the existence of a distinct recognition system for fungi to activate the Toll pathway.},
keywords = {Amino Acid, Animals, Anti-Bacterial Agents, Anti-Infective Agents, Bacillus thuringiensis, Carrier Proteins, Cell Surface, Chromosome Mapping, Enterococcus faecalis, Fungi, Genes, Gram-Positive Bacteria, Hemolymph, hoffmann, Humans, Insect, Insect Proteins, M3i, Membrane Glycoproteins, Micrococcus luteus, Mutation, Receptors, reichhart, Sequence Homology, Toll-Like Receptors},
pubstate = {published},
tppubtype = {article}
}
Microbial infection activates two distinct intracellular signalling cascades in the immune-responsive fat body of Drosophila. Gram-positive bacteria and fungi predominantly induce the Toll signalling pathway, whereas Gram-negative bacteria activate the Imd pathway. Loss-of-function mutants in either pathway reduce the resistance to corresponding infections. Genetic screens have identified a range of genes involved in these intracellular signalling cascades, but how they are activated by microbial infection is largely unknown. Activation of the transmembrane receptor Toll requires a proteolytically cleaved form of an extracellular cytokine-like polypeptide, Spätzle, suggesting that Toll does not itself function as a bona fide recognition receptor of microbial patterns. This is in apparent contrast with the mammalian Toll-like receptors and raises the question of which host molecules actually recognize microbial patterns to activate Toll through Spätzle. Here we present a mutation that blocks Toll activation by Gram-positive bacteria and significantly decreases resistance to this type of infection. The mutation semmelweis (seml) inactivates the gene encoding a peptidoglycan recognition protein (PGRP-SA). Interestingly, seml does not affect Toll activation by fungal infection, indicating the existence of a distinct recognition system for fungi to activate the Toll pathway.
Georgel Philippe, Naitza S, Kappler Christine, Ferrandon Dominique, Zachary Daniel, Swimmer C, Kopczynski C, Duyk G, Reichhart Jean-Marc, Hoffmann Jules A
Drosophila immune deficiency (IMD) is a death domain protein that activates antibacterial defense and can promote apoptosis Article de journal
Dans: Dev. Cell, vol. 1, no. 4, p. 503–514, 2001, ISSN: 1534-5807.
Résumé | BibTeX | Étiquettes: Animals, Anti-Infective Agents, Apoptosis, Bacterial Infections, Caspases, Chromosome Mapping, Cysteine Proteinase Inhibitors, DNA Damage, Female, ferrandon, Gene Expression, hoffmann, I-kappa B Kinase, Immunocompromised Host, In Situ Nick-End Labeling, Insect Proteins, M3i, Male, Mutation, Phenotype, Protein Structure, Protein-Serine-Threonine Kinases, reichhart, Tertiary
@article{georgel_drosophila_2001,
title = {Drosophila immune deficiency (IMD) is a death domain protein that activates antibacterial defense and can promote apoptosis},
author = {Philippe Georgel and S Naitza and Christine Kappler and Dominique Ferrandon and Daniel Zachary and C Swimmer and C Kopczynski and G Duyk and Jean-Marc Reichhart and Jules A Hoffmann},
issn = {1534-5807},
year = {2001},
date = {2001-10-01},
journal = {Dev. Cell},
volume = {1},
number = {4},
pages = {503--514},
abstract = {We report the molecular characterization of the immune deficiency (imd) gene, which controls antibacterial defense in Drosophila. imd encodes a protein with a death domain similar to that of mammalian RIP (receptor interacting protein), a protein that plays a role in both NF-kappaB activation and apoptosis. We show that imd functions upstream of the DmIKK signalosome and the caspase DREDD in the control of antibacterial peptide genes. Strikingly, overexpression of imd leads to constitutive transcription of these genes and to apoptosis, and both effects are blocked by coexpression of the caspase inhibitor P35. We also show that imd is involved in the apoptotic response to UV irradiation. These data raise the possibility that antibacterial response and apoptosis share common control elements in Drosophila.},
keywords = {Animals, Anti-Infective Agents, Apoptosis, Bacterial Infections, Caspases, Chromosome Mapping, Cysteine Proteinase Inhibitors, DNA Damage, Female, ferrandon, Gene Expression, hoffmann, I-kappa B Kinase, Immunocompromised Host, In Situ Nick-End Labeling, Insect Proteins, M3i, Male, Mutation, Phenotype, Protein Structure, Protein-Serine-Threonine Kinases, reichhart, Tertiary},
pubstate = {published},
tppubtype = {article}
}
We report the molecular characterization of the immune deficiency (imd) gene, which controls antibacterial defense in Drosophila. imd encodes a protein with a death domain similar to that of mammalian RIP (receptor interacting protein), a protein that plays a role in both NF-kappaB activation and apoptosis. We show that imd functions upstream of the DmIKK signalosome and the caspase DREDD in the control of antibacterial peptide genes. Strikingly, overexpression of imd leads to constitutive transcription of these genes and to apoptosis, and both effects are blocked by coexpression of the caspase inhibitor P35. We also show that imd is involved in the apoptotic response to UV irradiation. These data raise the possibility that antibacterial response and apoptosis share common control elements in Drosophila.
Vizioli J, Bulet Philippe, Hoffmann Jules A, Kafatos Fotis C, Müller H M, Dimopoulos G
Gambicin: a novel immune responsive antimicrobial peptide from the malaria vector Anopheles gambiae Article de journal
Dans: Proc. Natl. Acad. Sci. U.S.A., vol. 98, no. 22, p. 12630–12635, 2001, ISSN: 0027-8424.
Résumé | Liens | BibTeX | Étiquettes: Animals, Anopheles, Anti-Bacterial Agents, Anti-Infective Agents, Base Sequence, Chromosome Mapping, hoffmann, Insect Proteins, Insect Vectors, M3i, Malaria, messenger, RNA
@article{vizioli_gambicin:_2001,
title = {Gambicin: a novel immune responsive antimicrobial peptide from the malaria vector Anopheles gambiae},
author = {J Vizioli and Philippe Bulet and Jules A Hoffmann and Fotis C Kafatos and H M Müller and G Dimopoulos},
doi = {10.1073/pnas.221466798},
issn = {0027-8424},
year = {2001},
date = {2001-10-01},
journal = {Proc. Natl. Acad. Sci. U.S.A.},
volume = {98},
number = {22},
pages = {12630--12635},
abstract = {A novel mosquito antimicrobial peptide, gambicin, and the corresponding gene were isolated in parallel through differential display-PCR, an expressed sequence tag (EST) project, and characterization of an antimicrobial activity in a mosquito cell line by reverse-phase chromatography. The 616-bp gambicin ORF encodes an 81-residue protein that is processed and secreted as a 61-aa mature peptide containing eight cysteines engaged in four disulfide bridges. Gambicin lacks sequence homology with other known proteins. Like other Anopheles gambiae antimicrobial peptide genes, gambicin is induced by natural or experimental infection in the midgut, fatbody, and hemocyte-like cell lines. Within the midgut, gambicin is predominantly expressed in the anterior part. Both local and systemic gambicin expression is induced during early and late stages of natural malaria infection. In vitro experiments showed that the 6.8-kDa mature peptide can kill both Gram-positive and Gram-negative bacteria, has a morphogenic effect on a filamentous fungus, and is marginally lethal to Plasmodium berghei ookinetes. An oxidized form of gambicin isolated from the cell line medium was more active against bacteria than the nonoxidized form from the same medium.},
keywords = {Animals, Anopheles, Anti-Bacterial Agents, Anti-Infective Agents, Base Sequence, Chromosome Mapping, hoffmann, Insect Proteins, Insect Vectors, M3i, Malaria, messenger, RNA},
pubstate = {published},
tppubtype = {article}
}
A novel mosquito antimicrobial peptide, gambicin, and the corresponding gene were isolated in parallel through differential display-PCR, an expressed sequence tag (EST) project, and characterization of an antimicrobial activity in a mosquito cell line by reverse-phase chromatography. The 616-bp gambicin ORF encodes an 81-residue protein that is processed and secreted as a 61-aa mature peptide containing eight cysteines engaged in four disulfide bridges. Gambicin lacks sequence homology with other known proteins. Like other Anopheles gambiae antimicrobial peptide genes, gambicin is induced by natural or experimental infection in the midgut, fatbody, and hemocyte-like cell lines. Within the midgut, gambicin is predominantly expressed in the anterior part. Both local and systemic gambicin expression is induced during early and late stages of natural malaria infection. In vitro experiments showed that the 6.8-kDa mature peptide can kill both Gram-positive and Gram-negative bacteria, has a morphogenic effect on a filamentous fungus, and is marginally lethal to Plasmodium berghei ookinetes. An oxidized form of gambicin isolated from the cell line medium was more active against bacteria than the nonoxidized form from the same medium.
Boulanger Nathalie, Ehret-Sabatier Laurence, Brun R, Zachary Daniel, Bulet Philippe, Imler Jean-Luc
Immune response of Drosophila melanogaster to infection with the flagellate parasite Crithidia spp Article de journal
Dans: Insect Biochemistry and Molecular Biology, vol. 31, no. 2, p. 129–137, 2001, ISSN: 0965-1748.
Résumé | BibTeX | Étiquettes: Animals, Anti-Bacterial Agents, Antimicrobial Cationic Peptides, Crithidia, Defensins, Gene Expression, Glycopeptides, Hemocytes, imler, Insect Proteins, M3i, Phagocytosis
@article{boulanger_immune_2001,
title = {Immune response of Drosophila melanogaster to infection with the flagellate parasite Crithidia spp},
author = {Nathalie Boulanger and Laurence Ehret-Sabatier and R Brun and Daniel Zachary and Philippe Bulet and Jean-Luc Imler},
issn = {0965-1748},
year = {2001},
date = {2001-02-01},
journal = {Insect Biochemistry and Molecular Biology},
volume = {31},
number = {2},
pages = {129--137},
abstract = {Insects are able to recognize invading microorganisms and to mount an immune response to bacterial and fungal infections. Recently, the fruitfly Drosophila melanogaster has emerged as a promising invertebrate model to investigate innate immunity because of its well-characterized genetics. Insects are also vectors of numerous parasites which can trigger an immune response. We have investigated the interaction of Drosophila melanogaster with the flagellate protozoan Crithidia spp. We show that a per os parasitic infection triggers the synthesis of several antimicrobial peptides. By reverse phase HPLC and mass spectrometry, peptides were shown to be present in the hemolymph and not in the gut tissue, suggesting the presence of immune messengers between the site of the infection, namely the gut, and the fat body, the main site of synthesis for antimicrobial peptides. Interestingly, we have identified one molecule which is specifically induced in the hemolymph after infection with Crithidia, but not with bacteria, suggesting that Drosophila can discriminate between pathogens. When flagellates were injected into the hemolymph, a low synthesis of antimicrobial peptides was observed together with phagocytosis of parasites by circulating hemocytes. The data presented here suggest that Drosophila-Crithidia spp. represents an interesting model to study host defense against protozoan parasites.},
keywords = {Animals, Anti-Bacterial Agents, Antimicrobial Cationic Peptides, Crithidia, Defensins, Gene Expression, Glycopeptides, Hemocytes, imler, Insect Proteins, M3i, Phagocytosis},
pubstate = {published},
tppubtype = {article}
}
Insects are able to recognize invading microorganisms and to mount an immune response to bacterial and fungal infections. Recently, the fruitfly Drosophila melanogaster has emerged as a promising invertebrate model to investigate innate immunity because of its well-characterized genetics. Insects are also vectors of numerous parasites which can trigger an immune response. We have investigated the interaction of Drosophila melanogaster with the flagellate protozoan Crithidia spp. We show that a per os parasitic infection triggers the synthesis of several antimicrobial peptides. By reverse phase HPLC and mass spectrometry, peptides were shown to be present in the hemolymph and not in the gut tissue, suggesting the presence of immune messengers between the site of the infection, namely the gut, and the fat body, the main site of synthesis for antimicrobial peptides. Interestingly, we have identified one molecule which is specifically induced in the hemolymph after infection with Crithidia, but not with bacteria, suggesting that Drosophila can discriminate between pathogens. When flagellates were injected into the hemolymph, a low synthesis of antimicrobial peptides was observed together with phagocytosis of parasites by circulating hemocytes. The data presented here suggest that Drosophila-Crithidia spp. represents an interesting model to study host defense against protozoan parasites.
Levashina Elena A, Moita L F, Blandin Stéphanie A, Vriend G, Lagueux Marie, Kafatos F C
Conserved role of a complement-like protein in phagocytosis revealed by dsRNA knockout in cultured cells of the mosquito, Anopheles gambiae Article de journal
Dans: Cell, vol. 104, no. 5, p. 709–718, 2001, ISSN: 0092-8674.
Résumé | BibTeX | Étiquettes: alpha-Macroglobulins, Animals, Anopheles, blandin, Cells, Cloning, Complement C3, Cultured, DNA Fragmentation, Double-Stranded, Female, Genetic, Gram-Negative Bacteria, Hemocytes, Insect Proteins, M3i, Molecular, Nucleic Acid Denaturation, Phagocytosis, Protein Structure, RNA, Tertiary, Transcription
@article{levashina_conserved_2001,
title = {Conserved role of a complement-like protein in phagocytosis revealed by dsRNA knockout in cultured cells of the mosquito, Anopheles gambiae},
author = {Elena A Levashina and L F Moita and Stéphanie A Blandin and G Vriend and Marie Lagueux and F C Kafatos},
issn = {0092-8674},
year = {2001},
date = {2001-01-01},
journal = {Cell},
volume = {104},
number = {5},
pages = {709--718},
abstract = {We characterize a novel hemocyte-specific acute phase glycoprotein from the malaria vector, Anopheles gambiae. It shows substantial structural and functional similarities, including the highly conserved thioester motif, to both a central component of mammalian complement system, factor C3, and to a pan-protease inhibitor, alpha2-macroglobulin. Most importantly, this protein serves as a complement-like opsonin and promotes phagocytosis of some Gram-negative bacteria in a mosquito hemocyte-like cell line. Chemical inactivation by methylamine and depletion by double-stranded RNA knockout demonstrate that this function is dependent on the internal thioester bond. This evidence of a complement-like function in a protostome animal adds substantially to the accumulating evidence of a common ancestry of immune defenses in insects and vertebrates.},
keywords = {alpha-Macroglobulins, Animals, Anopheles, blandin, Cells, Cloning, Complement C3, Cultured, DNA Fragmentation, Double-Stranded, Female, Genetic, Gram-Negative Bacteria, Hemocytes, Insect Proteins, M3i, Molecular, Nucleic Acid Denaturation, Phagocytosis, Protein Structure, RNA, Tertiary, Transcription},
pubstate = {published},
tppubtype = {article}
}
We characterize a novel hemocyte-specific acute phase glycoprotein from the malaria vector, Anopheles gambiae. It shows substantial structural and functional similarities, including the highly conserved thioester motif, to both a central component of mammalian complement system, factor C3, and to a pan-protease inhibitor, alpha2-macroglobulin. Most importantly, this protein serves as a complement-like opsonin and promotes phagocytosis of some Gram-negative bacteria in a mosquito hemocyte-like cell line. Chemical inactivation by methylamine and depletion by double-stranded RNA knockout demonstrate that this function is dependent on the internal thioester bond. This evidence of a complement-like function in a protostome animal adds substantially to the accumulating evidence of a common ancestry of immune defenses in insects and vertebrates.
2000
Lagueux Marie, Perrodou E, Levashina Elena A, Capovilla Maria, Hoffmann Jules A
Constitutive expression of a complement-like protein in toll and JAK gain-of-function mutants of Drosophila Article de journal
Dans: Proc. Natl. Acad. Sci. U.S.A., vol. 97, no. 21, p. 11427–11432, 2000, ISSN: 0027-8424.
Résumé | Liens | BibTeX | Étiquettes: alpha-Macroglobulins, Amino Acid, Animals, Cell Surface, Complement C3, Esters, Genetic, hoffmann, Insect Proteins, Janus Kinases, M3i, Membrane Glycoproteins, Mutation, Protein-Tyrosine Kinases, Proteins, Receptors, Sequence Homology, Sulfhydryl Compounds, Toll-Like Receptors, Transcription, Transcription Factors
@article{lagueux_constitutive_2000,
title = {Constitutive expression of a complement-like protein in toll and JAK gain-of-function mutants of Drosophila},
author = {Marie Lagueux and E Perrodou and Elena A Levashina and Maria Capovilla and Jules A Hoffmann},
doi = {10.1073/pnas.97.21.11427},
issn = {0027-8424},
year = {2000},
date = {2000-10-01},
journal = {Proc. Natl. Acad. Sci. U.S.A.},
volume = {97},
number = {21},
pages = {11427--11432},
abstract = {We show that Drosophila expresses four genes encoding proteins with significant similarities with the thiolester-containing proteins of the complement C3/alpha(2)-macroglobulin superfamily. The genes are transcribed at a low level during all stages of development, and their expression is markedly up-regulated after an immune challenge. For one of these genes, which is predominantly expressed in the larval fat body, we observe a constitutive expression in gain-of-function mutants of the Janus kinase (JAK) hop and a reduced inducibility in loss-of-function hop mutants. We also observe a constitutive expression in gain-of-function Toll mutants. We discuss the possible roles of these novel complement-like proteins in the Drosophila host defense.},
keywords = {alpha-Macroglobulins, Amino Acid, Animals, Cell Surface, Complement C3, Esters, Genetic, hoffmann, Insect Proteins, Janus Kinases, M3i, Membrane Glycoproteins, Mutation, Protein-Tyrosine Kinases, Proteins, Receptors, Sequence Homology, Sulfhydryl Compounds, Toll-Like Receptors, Transcription, Transcription Factors},
pubstate = {published},
tppubtype = {article}
}
We show that Drosophila expresses four genes encoding proteins with significant similarities with the thiolester-containing proteins of the complement C3/alpha(2)-macroglobulin superfamily. The genes are transcribed at a low level during all stages of development, and their expression is markedly up-regulated after an immune challenge. For one of these genes, which is predominantly expressed in the larval fat body, we observe a constitutive expression in gain-of-function mutants of the Janus kinase (JAK) hop and a reduced inducibility in loss-of-function hop mutants. We also observe a constitutive expression in gain-of-function Toll mutants. We discuss the possible roles of these novel complement-like proteins in the Drosophila host defense.
Rutschmann Sophie, Jung Alain C, Zhou R, Silverman N, Hoffmann Jules A, Ferrandon Dominique
Role of Drosophila IKK gamma in a toll-independent antibacterial immune response Article de journal
Dans: Nat. Immunol., vol. 1, no. 4, p. 342–347, 2000, ISSN: 1529-2908.
Résumé | Liens | BibTeX | Étiquettes: Animals, Antigens, Bacterial, Cell Surface, ferrandon, Gene Expression Regulation, hoffmann, I-kappa B Kinase, Immunity, Innate, Insect Proteins, M3i, Membrane Glycoproteins, Protein-Serine-Threonine Kinases, Receptors, Signal Transduction, Toll-Like Receptors, Transcription Factors
@article{rutschmann_role_2000,
title = {Role of Drosophila IKK gamma in a toll-independent antibacterial immune response},
author = {Sophie Rutschmann and Alain C Jung and R Zhou and N Silverman and Jules A Hoffmann and Dominique Ferrandon},
doi = {10.1038/79801},
issn = {1529-2908},
year = {2000},
date = {2000-10-01},
journal = {Nat. Immunol.},
volume = {1},
number = {4},
pages = {342--347},
abstract = {We have generated, by ethylmethane sulfonate mutagenesis, loss-of-function mutants in the Drosophila homolog of the mammalian I-kappa B kinase (IKK) complex component IKK gamma (also called NEMO). Our data show that Drosophila IKK gamma is required for the Relish-dependent immune induction of the genes encoding antibacterial peptides and for resistance to infections by Escherichia coli. However, it is not required for the Toll-DIF-dependent antifungal host defense. The results indicate distinct control mechanisms of the Rel-like transactivators DIF and Relish in the Drosophila innate immune response and show that Drosophila Toll does not signal through a IKK gamma-dependent signaling complex. Thus, in contrast to the vertebrate inflammatory response, IKK gamma is required for the activation of only one immune signaling pathway in Drosophila.},
keywords = {Animals, Antigens, Bacterial, Cell Surface, ferrandon, Gene Expression Regulation, hoffmann, I-kappa B Kinase, Immunity, Innate, Insect Proteins, M3i, Membrane Glycoproteins, Protein-Serine-Threonine Kinases, Receptors, Signal Transduction, Toll-Like Receptors, Transcription Factors},
pubstate = {published},
tppubtype = {article}
}
We have generated, by ethylmethane sulfonate mutagenesis, loss-of-function mutants in the Drosophila homolog of the mammalian I-kappa B kinase (IKK) complex component IKK gamma (also called NEMO). Our data show that Drosophila IKK gamma is required for the Relish-dependent immune induction of the genes encoding antibacterial peptides and for resistance to infections by Escherichia coli. However, it is not required for the Toll-DIF-dependent antifungal host defense. The results indicate distinct control mechanisms of the Rel-like transactivators DIF and Relish in the Drosophila innate immune response and show that Drosophila Toll does not signal through a IKK gamma-dependent signaling complex. Thus, in contrast to the vertebrate inflammatory response, IKK gamma is required for the activation of only one immune signaling pathway in Drosophila.
Basset A, Khush R S, Braun A, Gardan L, Boccard F, Hoffmann Jules A, Lemaitre Bruno
The phytopathogenic bacteria Erwinia carotovora infects Drosophila and activates an immune response Article de journal
Dans: Proc. Natl. Acad. Sci. U.S.A., vol. 97, no. 7, p. 3376–3381, 2000, ISSN: 0027-8424.
Résumé | Liens | BibTeX | Étiquettes: Animals, Bacterial, Gene Expression Regulation, Genetically Modified, hoffmann, Insect Proteins, Larva, M3i, Pectobacterium carotovorum
@article{basset_phytopathogenic_2000,
title = {The phytopathogenic bacteria Erwinia carotovora infects Drosophila and activates an immune response},
author = {A Basset and R S Khush and A Braun and L Gardan and F Boccard and Jules A Hoffmann and Bruno Lemaitre},
doi = {10.1073/pnas.070357597},
issn = {0027-8424},
year = {2000},
date = {2000-03-01},
journal = {Proc. Natl. Acad. Sci. U.S.A.},
volume = {97},
number = {7},
pages = {3376--3381},
abstract = {Although Drosophila possesses potent immune responses, little is known about the microbial pathogens that infect Drosophila. We have identified members of the bacterial genus Erwinia that induce the systemic expression of genes encoding antimicrobial peptides in Drosophila larvae after ingestion. These Erwinia strains are phytopathogens and use flies as vectors; our data suggest that these strains have also evolved mechanisms for exploiting their insect vectors as hosts. Erwinia infections induce an antimicrobial response in Drosophila larvae with a preferential expression of antibacterial versus antifungal peptide-encoding genes. Antibacterial peptide gene expression after Erwinia infection is reduced in two Drosophila mutants that have reduced numbers of hemocytes, suggesting that blood cells play a role in regulating Drosophila antimicrobial responses and also illustrating that this Drosophila-Erwinia interaction provides a powerful model for dissecting host-pathogen relationships.},
keywords = {Animals, Bacterial, Gene Expression Regulation, Genetically Modified, hoffmann, Insect Proteins, Larva, M3i, Pectobacterium carotovorum},
pubstate = {published},
tppubtype = {article}
}
Although Drosophila possesses potent immune responses, little is known about the microbial pathogens that infect Drosophila. We have identified members of the bacterial genus Erwinia that induce the systemic expression of genes encoding antimicrobial peptides in Drosophila larvae after ingestion. These Erwinia strains are phytopathogens and use flies as vectors; our data suggest that these strains have also evolved mechanisms for exploiting their insect vectors as hosts. Erwinia infections induce an antimicrobial response in Drosophila larvae with a preferential expression of antibacterial versus antifungal peptide-encoding genes. Antibacterial peptide gene expression after Erwinia infection is reduced in two Drosophila mutants that have reduced numbers of hemocytes, suggesting that blood cells play a role in regulating Drosophila antimicrobial responses and also illustrating that this Drosophila-Erwinia interaction provides a powerful model for dissecting host-pathogen relationships.
Imler Jean-Luc, Hoffmann Jules A
Signaling mechanisms in the antimicrobial host defense of Drosophila Article de journal
Dans: Current Opinion in Microbiology, vol. 3, no. 1, p. 16–22, 2000, ISSN: 1369-5274.
Résumé | BibTeX | Étiquettes: Animals, Anti-Infective Agents, Cell Surface, Gene Expression Regulation, Genes, hoffmann, imler, Insect, Insect Proteins, M3i, Membrane Glycoproteins, Receptors, Signal Transduction, Toll-Like Receptors
@article{imler_signaling_2000,
title = {Signaling mechanisms in the antimicrobial host defense of Drosophila},
author = {Jean-Luc Imler and Jules A Hoffmann},
issn = {1369-5274},
year = {2000},
date = {2000-02-01},
journal = {Current Opinion in Microbiology},
volume = {3},
number = {1},
pages = {16--22},
abstract = {Drosophila has appeared in recent years as a powerful model to study innate immunity. Several papers published in the past year shed light on the role of the three Rel proteins Dorsal, Dif and Relish in the regulation of antimicrobial peptide expression. In addition, the discovery that a blood serine protease inhibitor is involved in the control of the antifungal response indicates that Toll is activated upon triggering of a proteolytic cascade and does not function as a Drosophila pattern recognition receptor.},
keywords = {Animals, Anti-Infective Agents, Cell Surface, Gene Expression Regulation, Genes, hoffmann, imler, Insect, Insect Proteins, M3i, Membrane Glycoproteins, Receptors, Signal Transduction, Toll-Like Receptors},
pubstate = {published},
tppubtype = {article}
}
Drosophila has appeared in recent years as a powerful model to study innate immunity. Several papers published in the past year shed light on the role of the three Rel proteins Dorsal, Dif and Relish in the regulation of antimicrobial peptide expression. In addition, the discovery that a blood serine protease inhibitor is involved in the control of the antifungal response indicates that Toll is activated upon triggering of a proteolytic cascade and does not function as a Drosophila pattern recognition receptor.
Hetru Charles, Letellier L, Oren Z, Hoffmann Jules A, Shai Y
Androctonin, a hydrophilic disulphide-bridged non-haemolytic anti-microbial peptide: a plausible mode of action Article de journal
Dans: Biochem. J., vol. 345 Pt 3, p. 653–664, 2000, ISSN: 0264-6021.
Résumé | BibTeX | Étiquettes: Adenosine Triphosphate, Anti-Bacterial Agents, Cations, Cell Membrane Permeability, Cytoplasm, Disulfides, Electron, Escherichia coli, Fluoresceins, Fluorescent Dyes, Fourier Transform Infrared, Gram-Negative Bacteria, hoffmann, Insect Proteins, Liposomes, M3i, Microbial Sensitivity Tests, Micrococcus luteus, Microscopy, oxygen, Phospholipids, Potassium, Proteins, spectroscopy
@article{hetru_androctonin_2000,
title = {Androctonin, a hydrophilic disulphide-bridged non-haemolytic anti-microbial peptide: a plausible mode of action},
author = {Charles Hetru and L Letellier and Z Oren and Jules A Hoffmann and Y Shai},
issn = {0264-6021},
year = {2000},
date = {2000-01-01},
journal = {Biochem. J.},
volume = {345 Pt 3},
pages = {653--664},
abstract = {Androctonin is a 25-residue non-haemolytic anti-microbial peptide isolated from the scorpion Androctonus australis and contains two disulphide bridges. Androctonin is different from known native anti-microbial peptides, being a relatively hydrophilic and non-amphipathic molecule. This raises the possibility that the target of androctonin might not be the bacterial membrane, shown to be a target for most amphipathic lytic peptides. To shed light on its mode of action on bacteria and its non-haemolytic activity, we synthesized androctonin, its fluorescent derivatives and its all-D-amino acid enantiomer. The enantiomer preserved high activity, suggesting a lipid-peptide interaction between androctonin and bacterial membranes. In Gram-positive and (at higher concentrations) Gram-negative bacteria, androctonin induced an immediate perturbation of the permeability properties of the cytoplasmic membrane of the bacterial energetic state, concomitant with perturbation of the morphology of the cell envelope as revealed by electron microscopy. Androctonin binds only to negatively charged lipid vesicles and induces the leakage of markers at high concentrations and with a slow kinetics, in contrast with amphipathic alpha-helical anti-microbial peptides that bind and permeate negatively charged vesicles, and to a smaller extent also zwitterionic ones. This might explain the selective lytic activity of androctonin towards bacteria but not red blood cells. Polarized attenuated total reflection-Fourier transform infrared spectroscopy revealed that androctonin adopts a beta-sheet structure in membranes and did not affect the lipid acyl chain order, which supports a detergent-like effect. The small size of androctonin, its hydrophilic character and its physicochemical properties are favourable features for its potential application as a replacement for commercially available antibiotics to which bacteria have developed resistance.},
keywords = {Adenosine Triphosphate, Anti-Bacterial Agents, Cations, Cell Membrane Permeability, Cytoplasm, Disulfides, Electron, Escherichia coli, Fluoresceins, Fluorescent Dyes, Fourier Transform Infrared, Gram-Negative Bacteria, hoffmann, Insect Proteins, Liposomes, M3i, Microbial Sensitivity Tests, Micrococcus luteus, Microscopy, oxygen, Phospholipids, Potassium, Proteins, spectroscopy},
pubstate = {published},
tppubtype = {article}
}
Androctonin is a 25-residue non-haemolytic anti-microbial peptide isolated from the scorpion Androctonus australis and contains two disulphide bridges. Androctonin is different from known native anti-microbial peptides, being a relatively hydrophilic and non-amphipathic molecule. This raises the possibility that the target of androctonin might not be the bacterial membrane, shown to be a target for most amphipathic lytic peptides. To shed light on its mode of action on bacteria and its non-haemolytic activity, we synthesized androctonin, its fluorescent derivatives and its all-D-amino acid enantiomer. The enantiomer preserved high activity, suggesting a lipid-peptide interaction between androctonin and bacterial membranes. In Gram-positive and (at higher concentrations) Gram-negative bacteria, androctonin induced an immediate perturbation of the permeability properties of the cytoplasmic membrane of the bacterial energetic state, concomitant with perturbation of the morphology of the cell envelope as revealed by electron microscopy. Androctonin binds only to negatively charged lipid vesicles and induces the leakage of markers at high concentrations and with a slow kinetics, in contrast with amphipathic alpha-helical anti-microbial peptides that bind and permeate negatively charged vesicles, and to a smaller extent also zwitterionic ones. This might explain the selective lytic activity of androctonin towards bacteria but not red blood cells. Polarized attenuated total reflection-Fourier transform infrared spectroscopy revealed that androctonin adopts a beta-sheet structure in membranes and did not affect the lipid acyl chain order, which supports a detergent-like effect. The small size of androctonin, its hydrophilic character and its physicochemical properties are favourable features for its potential application as a replacement for commercially available antibiotics to which bacteria have developed resistance.
Imler Jean-Luc, Tauszig Servane, Jouanguy Emmanuelle, Forestier C, Hoffmann Jules A
LPS-induced immune response in Drosophila Article de journal
Dans: Journal of Endotoxin Research, vol. 6, no. 6, p. 459–462, 2000, ISSN: 0968-0519.
Résumé | BibTeX | Étiquettes: Animals, Biological, Cell Line, Cell Surface, Defensins, Genes, Genetic, hoffmann, imler, Insect, Insect Proteins, Lipopolysaccharides, M3i, Membrane Glycoproteins, Models, Mutation, Promoter Regions, Receptors, Signal Transduction, Toll-Like Receptors
@article{imler_lps-induced_2000,
title = {LPS-induced immune response in Drosophila},
author = {Jean-Luc Imler and Servane Tauszig and Emmanuelle Jouanguy and C Forestier and Jules A Hoffmann},
issn = {0968-0519},
year = {2000},
date = {2000-01-01},
journal = {Journal of Endotoxin Research},
volume = {6},
number = {6},
pages = {459--462},
abstract = {The study of the regulation of the inducible synthesis of antimicrobial peptides in Drosophila melanogaster has established this insect as a powerful model in which to study innate immunity. In particular, the molecular characterization of the regulatory pathway controlling the antifungal peptide drosomycin has revealed the importance of Toll receptors in innate immunity. We report here that injection of LPS into flies induces an immune response, suggesting that LPS receptors are used in Drosophila to detect Gram-negative bacteria infection. We have identified in the recently sequenced genome of Drosophila eight genes coding for Toll-like receptors in addition to Toll, which may function as LPS receptors. However, overexpression of a selection of these genes in tissue-culture cells does not result in up-regulation of the antibacterial peptide genes. These results are discussed in light of the recent data from genetic screens aimed at identifying the genes controlling the antibacterial response in Drosophila.},
keywords = {Animals, Biological, Cell Line, Cell Surface, Defensins, Genes, Genetic, hoffmann, imler, Insect, Insect Proteins, Lipopolysaccharides, M3i, Membrane Glycoproteins, Models, Mutation, Promoter Regions, Receptors, Signal Transduction, Toll-Like Receptors},
pubstate = {published},
tppubtype = {article}
}
The study of the regulation of the inducible synthesis of antimicrobial peptides in Drosophila melanogaster has established this insect as a powerful model in which to study innate immunity. In particular, the molecular characterization of the regulatory pathway controlling the antifungal peptide drosomycin has revealed the importance of Toll receptors in innate immunity. We report here that injection of LPS into flies induces an immune response, suggesting that LPS receptors are used in Drosophila to detect Gram-negative bacteria infection. We have identified in the recently sequenced genome of Drosophila eight genes coding for Toll-like receptors in addition to Toll, which may function as LPS receptors. However, overexpression of a selection of these genes in tissue-culture cells does not result in up-regulation of the antibacterial peptide genes. These results are discussed in light of the recent data from genetic screens aimed at identifying the genes controlling the antibacterial response in Drosophila.
Meister Marie, Hetru Charles, Hoffmann Jules A
The antimicrobial host defense of Drosophila Article de journal
Dans: Curr. Top. Microbiol. Immunol., vol. 248, p. 17–36, 2000, ISSN: 0070-217X.
BibTeX | Étiquettes: Animals, Anti-Infective Agents, Fat Body, Genes, hoffmann, Insect, Insect Proteins, M3i
@article{meister_antimicrobial_2000,
title = {The antimicrobial host defense of Drosophila},
author = {Marie Meister and Charles Hetru and Jules A Hoffmann},
issn = {0070-217X},
year = {2000},
date = {2000-01-01},
journal = {Curr. Top. Microbiol. Immunol.},
volume = {248},
pages = {17--36},
keywords = {Animals, Anti-Infective Agents, Fat Body, Genes, hoffmann, Insect, Insect Proteins, M3i},
pubstate = {published},
tppubtype = {article}
}
Imler Jean-Luc, Hoffmann Jules A
Toll and Toll-like proteins: an ancient family of receptors signaling infection Article de journal
Dans: Reviews in Immunogenetics, vol. 2, no. 3, p. 294–304, 2000, ISSN: 1398-1714.
Résumé | BibTeX | Étiquettes: Adaptor Proteins, Animals, Antigens, Autoantigens, CD14, Cell Adhesion Molecules, Cell Surface, Differentiation, DNA-Binding Proteins, Gene Expression Regulation, hoffmann, I-kappa B Proteins, imler, Immunity, Immunologic, infection, Innate, Insect Proteins, Interleukin-1 Receptor-Associated Kinases, Knockout, Larva, Lipopolysaccharides, M3i, Mammals, MAP Kinase Signaling System, Membrane Glycoproteins, Membrane Proteins, Mice, Multigene Family, Myeloid Differentiation Factor 88, NF-kappa B, peptidoglycan, Phosphorylation, Post-Translational, Protein Kinases, Protein Processing, Protein Structure, Receptors, Recombinant Fusion Proteins, Signal Transducing, Signal Transduction, Teichoic Acids, Tertiary, Toll-Like Receptor 4, Toll-Like Receptor 5, Toll-Like Receptor 6, Toll-Like Receptor 9, Toll-Like Receptors, Ubiquitins
@article{imler_toll_2000,
title = {Toll and Toll-like proteins: an ancient family of receptors signaling infection},
author = {Jean-Luc Imler and Jules A Hoffmann},
issn = {1398-1714},
year = {2000},
date = {2000-01-01},
journal = {Reviews in Immunogenetics},
volume = {2},
number = {3},
pages = {294--304},
abstract = {Innate immunity is the first-line host defense of multicellular organisms that rapidly operates to limit infection upon exposure to microbes. It involves intracellular signaling pathways in the fruit-fly Drosophila and in mammals that show striking similarities. Recent genetic and biochemical data have revealed, in particular, that proteins of the Toll family play a critical role in the immediate response to infection. We review here the recent developments on the structural and functional characterization of this evolutionary ancient and important family of proteins, which can function as cytokine receptors (Toll in Drosophila) or pattern recognition receptors (TLR4 in mammals) and activate similar, albeit non identical signal transduction pathways, in flies and mammals.},
keywords = {Adaptor Proteins, Animals, Antigens, Autoantigens, CD14, Cell Adhesion Molecules, Cell Surface, Differentiation, DNA-Binding Proteins, Gene Expression Regulation, hoffmann, I-kappa B Proteins, imler, Immunity, Immunologic, infection, Innate, Insect Proteins, Interleukin-1 Receptor-Associated Kinases, Knockout, Larva, Lipopolysaccharides, M3i, Mammals, MAP Kinase Signaling System, Membrane Glycoproteins, Membrane Proteins, Mice, Multigene Family, Myeloid Differentiation Factor 88, NF-kappa B, peptidoglycan, Phosphorylation, Post-Translational, Protein Kinases, Protein Processing, Protein Structure, Receptors, Recombinant Fusion Proteins, Signal Transducing, Signal Transduction, Teichoic Acids, Tertiary, Toll-Like Receptor 4, Toll-Like Receptor 5, Toll-Like Receptor 6, Toll-Like Receptor 9, Toll-Like Receptors, Ubiquitins},
pubstate = {published},
tppubtype = {article}
}
Innate immunity is the first-line host defense of multicellular organisms that rapidly operates to limit infection upon exposure to microbes. It involves intracellular signaling pathways in the fruit-fly Drosophila and in mammals that show striking similarities. Recent genetic and biochemical data have revealed, in particular, that proteins of the Toll family play a critical role in the immediate response to infection. We review here the recent developments on the structural and functional characterization of this evolutionary ancient and important family of proteins, which can function as cytokine receptors (Toll in Drosophila) or pattern recognition receptors (TLR4 in mammals) and activate similar, albeit non identical signal transduction pathways, in flies and mammals.
1999
Levashina Elena A, Langley E, Green C, Gubb David, Ashburner M, Hoffmann Jules A, Reichhart Jean-Marc
Constitutive activation of toll-mediated antifungal defense in serpin-deficient Drosophila Article de journal
Dans: Science, vol. 285, no. 5435, p. 1917–1919, 1999, ISSN: 0036-8075.
Résumé | BibTeX | Étiquettes: Animals, Antifungal Agents, Antimicrobial Cationic Peptides, Body Patterning, Cell Surface, Escherichia coli, Genes, Hemolymph, hoffmann, Insect, Insect Proteins, M3i, Membrane Glycoproteins, Micrococcus luteus, Mutagenesis, Peptides, Receptors, Recombinant Fusion Proteins, reichhart, Serine Proteinase Inhibitors, Serpins, Signal Transduction, Toll-Like Receptors, Up-Regulation
@article{levashina_constitutive_1999,
title = {Constitutive activation of toll-mediated antifungal defense in serpin-deficient Drosophila},
author = {Elena A Levashina and E Langley and C Green and David Gubb and M Ashburner and Jules A Hoffmann and Jean-Marc Reichhart},
issn = {0036-8075},
year = {1999},
date = {1999-09-01},
journal = {Science},
volume = {285},
number = {5435},
pages = {1917--1919},
abstract = {The antifungal defense of Drosophila is controlled by the spaetzle/Toll/cactus gene cassette. Here, a loss-of-function mutation in the gene encoding a blood serine protease inhibitor, Spn43Ac, was shown to lead to constitutive expression of the antifungal peptide drosomycin, and this effect was mediated by the spaetzle and Toll gene products. Spaetzle was cleaved by proteolytic enzymes to its active ligand form shortly after immune challenge, and cleaved Spaetzle was constitutively present in Spn43Ac-deficient flies. Hence, Spn43Ac negatively regulates the Toll signaling pathway, and Toll does not function as a pattern recognition receptor in the Drosophila host defense.},
keywords = {Animals, Antifungal Agents, Antimicrobial Cationic Peptides, Body Patterning, Cell Surface, Escherichia coli, Genes, Hemolymph, hoffmann, Insect, Insect Proteins, M3i, Membrane Glycoproteins, Micrococcus luteus, Mutagenesis, Peptides, Receptors, Recombinant Fusion Proteins, reichhart, Serine Proteinase Inhibitors, Serpins, Signal Transduction, Toll-Like Receptors, Up-Regulation},
pubstate = {published},
tppubtype = {article}
}
The antifungal defense of Drosophila is controlled by the spaetzle/Toll/cactus gene cassette. Here, a loss-of-function mutation in the gene encoding a blood serine protease inhibitor, Spn43Ac, was shown to lead to constitutive expression of the antifungal peptide drosomycin, and this effect was mediated by the spaetzle and Toll gene products. Spaetzle was cleaved by proteolytic enzymes to its active ligand form shortly after immune challenge, and cleaved Spaetzle was constitutively present in Spn43Ac-deficient flies. Hence, Spn43Ac negatively regulates the Toll signaling pathway, and Toll does not function as a pattern recognition receptor in the Drosophila host defense.
Manfruelli P, Reichhart Jean-Marc, Steward R, Hoffmann Jules A, Lemaitre Bruno
A mosaic analysis in Drosophila fat body cells of the control of antimicrobial peptide genes by the Rel proteins Dorsal and DIF Article de journal
Dans: EMBO J., vol. 18, no. 12, p. 3380–3391, 1999, ISSN: 0261-4189.
Résumé | Liens | BibTeX | Étiquettes: Animals, Anti-Infective Agents, Cell Surface, Clone Cells, DNA-Binding Proteins, Fat Body, Female, Gene Expression Regulation, Genes, hoffmann, Insect, Insect Proteins, Larva, M3i, Male, Membrane Glycoproteins, Mosaicism, Mutation, Nuclear Proteins, Phosphoproteins, Receptors, reichhart, Reporter, Signal Transduction, Toll-Like Receptors, Transcription Factors
@article{manfruelli_mosaic_1999,
title = {A mosaic analysis in Drosophila fat body cells of the control of antimicrobial peptide genes by the Rel proteins Dorsal and DIF},
author = {P Manfruelli and Jean-Marc Reichhart and R Steward and Jules A Hoffmann and Bruno Lemaitre},
doi = {10.1093/emboj/18.12.3380},
issn = {0261-4189},
year = {1999},
date = {1999-06-01},
journal = {EMBO J.},
volume = {18},
number = {12},
pages = {3380--3391},
abstract = {Expression of the gene encoding the antifungal peptide Drosomycin in Drosophila adults is controlled by the Toll signaling pathway. The Rel proteins Dorsal and DIF (Dorsal-related immunity factor) are possible candidates for the transactivating protein in the Toll pathway that directly regulates the drosomycin gene. We have examined the requirement of Dorsal and DIF for drosomycin expression in larval fat body cells, the predominant immune-responsive tissue, using the yeast site-specific flp/FRT recombination system to generate cell clones homozygous for a deficiency uncovering both the dorsal and the dif genes. Here we show that in the absence of both genes, the immune-inducibility of drosomycin is lost but can be rescued by overexpression of either dorsal or dif under the control of a heat-shock promoter. This result suggests a functional redundancy between both Rel proteins in the control of drosomycin gene expression in the larvae of Drosophila. Interestingly, the gene encoding the antibacterial peptide Diptericin remains fully inducible in the absence of the dorsal and dif genes. Finally, we have used fat body cell clones homozygous for various mutations to show that a linear activation cascade Spaetzle--textgreater Toll--textgreaterCactus--textgreaterDorsal/DIF leads to the induction of the drosomycin gene in larval fat body cells.},
keywords = {Animals, Anti-Infective Agents, Cell Surface, Clone Cells, DNA-Binding Proteins, Fat Body, Female, Gene Expression Regulation, Genes, hoffmann, Insect, Insect Proteins, Larva, M3i, Male, Membrane Glycoproteins, Mosaicism, Mutation, Nuclear Proteins, Phosphoproteins, Receptors, reichhart, Reporter, Signal Transduction, Toll-Like Receptors, Transcription Factors},
pubstate = {published},
tppubtype = {article}
}
Expression of the gene encoding the antifungal peptide Drosomycin in Drosophila adults is controlled by the Toll signaling pathway. The Rel proteins Dorsal and DIF (Dorsal-related immunity factor) are possible candidates for the transactivating protein in the Toll pathway that directly regulates the drosomycin gene. We have examined the requirement of Dorsal and DIF for drosomycin expression in larval fat body cells, the predominant immune-responsive tissue, using the yeast site-specific flp/FRT recombination system to generate cell clones homozygous for a deficiency uncovering both the dorsal and the dif genes. Here we show that in the absence of both genes, the immune-inducibility of drosomycin is lost but can be rescued by overexpression of either dorsal or dif under the control of a heat-shock promoter. This result suggests a functional redundancy between both Rel proteins in the control of drosomycin gene expression in the larvae of Drosophila. Interestingly, the gene encoding the antibacterial peptide Diptericin remains fully inducible in the absence of the dorsal and dif genes. Finally, we have used fat body cell clones homozygous for various mutations to show that a linear activation cascade Spaetzle--textgreater Toll--textgreaterCactus--textgreaterDorsal/DIF leads to the induction of the drosomycin gene in larval fat body cells.
Lamberty M, Ades S, Uttenweiler-Joseph S, Brookhart G, Bushey D, Hoffmann Jules A, Bulet Philippe
Insect immunity. Isolation from the lepidopteran Heliothis virescens of a novel insect defensin with potent antifungal activity Article de journal
Dans: J. Biol. Chem., vol. 274, no. 14, p. 9320–9326, 1999, ISSN: 0021-9258.
Résumé | BibTeX | Étiquettes: Amino Acid, Animals, Antifungal Agents, Capillary, Chromatography, Defensins, Electrophoresis, Escherichia coli, Hemolymph, High Pressure Liquid, hoffmann, Insect Proteins, Larva, Lepidoptera, M3i, Micrococcus luteus, Proteins, Sequence Homology
@article{lamberty_insect_1999,
title = {Insect immunity. Isolation from the lepidopteran Heliothis virescens of a novel insect defensin with potent antifungal activity},
author = {M Lamberty and S Ades and S Uttenweiler-Joseph and G Brookhart and D Bushey and Jules A Hoffmann and Philippe Bulet},
issn = {0021-9258},
year = {1999},
date = {1999-04-01},
journal = {J. Biol. Chem.},
volume = {274},
number = {14},
pages = {9320--9326},
abstract = {Lepidoptera have been reported to produce several antibacterial peptides in response to septic injury. However, in marked contrast to other insect groups, no inducible antifungal molecules had been described so far in this insect order. Surprisingly, also cysteine-rich antimicrobial peptides, which predominate in the antimicrobial defense of other insects, had not been discovered in Lepidoptera. Here we report the isolation from the hemolymph of immune induced larvae of the lepidopteran Heliothis virescens of a cysteine-rich molecule with exclusive antifungal activity. We have fully characterized this antifungal molecule, which has significant homology with the insect defensins, a large family of antibacterial peptides directed against Gram-positive strains. Interestingly, the novel peptide shows also similarities with the antifungal peptide drosomycin from Drosophila. Thus, Lepidoptera appear to have built their humoral immune response against bacteria on cecropins and attacins. In addition, we report that Lepidoptera have conferred antifungal properties to the well conserved structure of antibacterial insect defensins through amino acid replacements.},
keywords = {Amino Acid, Animals, Antifungal Agents, Capillary, Chromatography, Defensins, Electrophoresis, Escherichia coli, Hemolymph, High Pressure Liquid, hoffmann, Insect Proteins, Larva, Lepidoptera, M3i, Micrococcus luteus, Proteins, Sequence Homology},
pubstate = {published},
tppubtype = {article}
}
Lepidoptera have been reported to produce several antibacterial peptides in response to septic injury. However, in marked contrast to other insect groups, no inducible antifungal molecules had been described so far in this insect order. Surprisingly, also cysteine-rich antimicrobial peptides, which predominate in the antimicrobial defense of other insects, had not been discovered in Lepidoptera. Here we report the isolation from the hemolymph of immune induced larvae of the lepidopteran Heliothis virescens of a cysteine-rich molecule with exclusive antifungal activity. We have fully characterized this antifungal molecule, which has significant homology with the insect defensins, a large family of antibacterial peptides directed against Gram-positive strains. Interestingly, the novel peptide shows also similarities with the antifungal peptide drosomycin from Drosophila. Thus, Lepidoptera appear to have built their humoral immune response against bacteria on cecropins and attacins. In addition, we report that Lepidoptera have conferred antifungal properties to the well conserved structure of antibacterial insect defensins through amino acid replacements.
1998
Uttenweiler-Joseph S, Moniatte M, Lagueux Marie, Dorsselaer Van A, Hoffmann Jules A, Bulet Philippe
Differential display of peptides induced during the immune response of Drosophila: a matrix-assisted laser desorption ionization time-of-flight mass spectrometry study Article de journal
Dans: Proc. Natl. Acad. Sci. U.S.A., vol. 95, no. 19, p. 11342–11347, 1998, ISSN: 0027-8424.
Résumé | BibTeX | Étiquettes: Animals, bacteria, Chromatography, Cloning, Hemolymph, High Pressure Liquid, hoffmann, Immunity, Insect Proteins, M3i, Mass, Matrix-Assisted Laser Desorption-Ionization, messenger, Molecular, Peptides, Protein Precursors, RNA, Sequence Analysis, Spectrometry, Time Factors
@article{uttenweiler-joseph_differential_1998,
title = {Differential display of peptides induced during the immune response of Drosophila: a matrix-assisted laser desorption ionization time-of-flight mass spectrometry study},
author = {S Uttenweiler-Joseph and M Moniatte and Marie Lagueux and Van A Dorsselaer and Jules A Hoffmann and Philippe Bulet},
issn = {0027-8424},
year = {1998},
date = {1998-09-01},
journal = {Proc. Natl. Acad. Sci. U.S.A.},
volume = {95},
number = {19},
pages = {11342--11347},
abstract = {We have developed an approach based on a differential mass spectrometric analysis to detect molecules induced during the immune response of Drosophila, regardless of their biological activities. For this, we have applied directly matrix-assisted laser desorption/ionization MS to hemolymph samples from individual flies before and after an immune challenge. This method provided precise information on the molecular masses of immune-induced molecules and allowed the detection, in the molecular range of 1.5-11 kDa, of 24 Drosophila immune-induced molecules (DIMs). These molecules are all peptides, and four correspond to already characterized antimicrobial peptides. We have further analyzed the induction of the various peptides by immune challenge in wild-type flies and in mutants with a compromised antimicrobial response. We also describe a methodology combining matrix-assisted laser desorption ionization time-of-flight MS, HPLC, and Edman degradation, which yielded the peptide sequence of three of the DIMs. Finally, molecular cloning and Northern blot analyses revealed that one of the DIMs is produced as a prepropeptide and is inducible on a bacterial challenge.},
keywords = {Animals, bacteria, Chromatography, Cloning, Hemolymph, High Pressure Liquid, hoffmann, Immunity, Insect Proteins, M3i, Mass, Matrix-Assisted Laser Desorption-Ionization, messenger, Molecular, Peptides, Protein Precursors, RNA, Sequence Analysis, Spectrometry, Time Factors},
pubstate = {published},
tppubtype = {article}
}
We have developed an approach based on a differential mass spectrometric analysis to detect molecules induced during the immune response of Drosophila, regardless of their biological activities. For this, we have applied directly matrix-assisted laser desorption/ionization MS to hemolymph samples from individual flies before and after an immune challenge. This method provided precise information on the molecular masses of immune-induced molecules and allowed the detection, in the molecular range of 1.5-11 kDa, of 24 Drosophila immune-induced molecules (DIMs). These molecules are all peptides, and four correspond to already characterized antimicrobial peptides. We have further analyzed the induction of the various peptides by immune challenge in wild-type flies and in mutants with a compromised antimicrobial response. We also describe a methodology combining matrix-assisted laser desorption ionization time-of-flight MS, HPLC, and Edman degradation, which yielded the peptide sequence of three of the DIMs. Finally, molecular cloning and Northern blot analyses revealed that one of the DIMs is produced as a prepropeptide and is inducible on a bacterial challenge.
Ferrandon Dominique, Jung Alain C, Criqui M, Lemaitre Bruno, Uttenweiler-Joseph S, Michaut Lydia, Reichhart Jean-Marc, Hoffmann Jules A
A drosomycin-GFP reporter transgene reveals a local immune response in Drosophila that is not dependent on the Toll pathway Article de journal
Dans: EMBO J., vol. 17, no. 5, p. 1217–1227, 1998, ISSN: 0261-4189.
Résumé | Liens | BibTeX | Étiquettes: Animals, bacteria, Cell Surface, Developmental, Digestive System, Epithelium, Fat Body, Female, ferrandon, Fungal, Gene Expression Regulation, Genes, Green Fluorescent Proteins, hoffmann, Insect Proteins, Larva, Luminescent Proteins, M3i, Male, Membrane Glycoproteins, Organ Specificity, Receptors, reichhart, Reporter, Respiratory System, Spores, Toll-Like Receptors, Trachea, Transgenes
@article{ferrandon_drosomycin-gfp_1998,
title = {A drosomycin-GFP reporter transgene reveals a local immune response in Drosophila that is not dependent on the Toll pathway},
author = {Dominique Ferrandon and Alain C Jung and M Criqui and Bruno Lemaitre and S Uttenweiler-Joseph and Lydia Michaut and Jean-Marc Reichhart and Jules A Hoffmann},
doi = {10.1093/emboj/17.5.1217},
issn = {0261-4189},
year = {1998},
date = {1998-08-01},
journal = {EMBO J.},
volume = {17},
number = {5},
pages = {1217--1227},
abstract = {A hallmark of the systemic antimicrobial response of Drosophila is the synthesis by the fat body of several antimicrobial peptides which are released into the hemolymph in response to a septic injury. One of these peptides, drosomycin, is active primarily against fungi. Using a drosomycin-green fluorescent protein (GFP) reporter gene, we now show that in addition to the fat body, a variety of epithelial tissues that are in direct contact with the external environment, including those of the respiratory, digestive and reproductive tracts, can express the antifungal peptide, suggesting a local response to infections affecting these barrier tissues. As is the case for vertebrate epithelia, insect epithelia appear to be more than passive physical barriers and are likely to constitute an active component of innate immunity. We also show that, in contrast to the systemic antifungal response, this local immune response is independent of the Toll pathway.},
keywords = {Animals, bacteria, Cell Surface, Developmental, Digestive System, Epithelium, Fat Body, Female, ferrandon, Fungal, Gene Expression Regulation, Genes, Green Fluorescent Proteins, hoffmann, Insect Proteins, Larva, Luminescent Proteins, M3i, Male, Membrane Glycoproteins, Organ Specificity, Receptors, reichhart, Reporter, Respiratory System, Spores, Toll-Like Receptors, Trachea, Transgenes},
pubstate = {published},
tppubtype = {article}
}
A hallmark of the systemic antimicrobial response of Drosophila is the synthesis by the fat body of several antimicrobial peptides which are released into the hemolymph in response to a septic injury. One of these peptides, drosomycin, is active primarily against fungi. Using a drosomycin-green fluorescent protein (GFP) reporter gene, we now show that in addition to the fat body, a variety of epithelial tissues that are in direct contact with the external environment, including those of the respiratory, digestive and reproductive tracts, can express the antifungal peptide, suggesting a local response to infections affecting these barrier tissues. As is the case for vertebrate epithelia, insect epithelia appear to be more than passive physical barriers and are likely to constitute an active component of innate immunity. We also show that, in contrast to the systemic antifungal response, this local immune response is independent of the Toll pathway.
Taguchi S, Bulet Philippe, Hoffmann Jules A
A novel insect defensin from the ant Formica rufa Article de journal
Dans: Biochimie, vol. 80, no. 4, p. 343–346, 1998, ISSN: 0300-9084.
Résumé | BibTeX | Étiquettes: Amino Acid, Animals, Anti-Bacterial Agents, Ants, Chromatography, High Pressure Liquid, hoffmann, Insect Proteins, insects, M3i, Mass, Matrix-Assisted Laser Desorption-Ionization, Protein Structure, Secondary, Sequence Alignment, Sequence Homology, Spectrometry
@article{taguchi_novel_1998,
title = {A novel insect defensin from the ant Formica rufa},
author = {S Taguchi and Philippe Bulet and Jules A Hoffmann},
issn = {0300-9084},
year = {1998},
date = {1998-04-01},
journal = {Biochimie},
volume = {80},
number = {4},
pages = {343--346},
abstract = {By combination of size exclusion and reversed-phase chromatography, we have isolated a novel member of insect defensin-type antimicrobial peptides from the entire bodies of bacteria-challenged Formica rufa (hymenoptera, formicidae). The molecular mass of the purified peptide was estimated to be 4120.42 by matrix-assisted laser desorption/ionization-time of flight/mass spectrometry. Sequence analysis revealed that this peptide consisted of 40 amino acid residues with six cysteines engaged in the formation of three intramolecular disulfide bridges. This peptide is unique among the arthropod defensins in terms of the presence of asparatic acid and alanine at position 33 and as C-terminal residue, respectively. In addition, this novel defensin from Formica rufa has the particularity to have no C-terminal extension in contrast to those reported for other hymenoptera defensins.},
keywords = {Amino Acid, Animals, Anti-Bacterial Agents, Ants, Chromatography, High Pressure Liquid, hoffmann, Insect Proteins, insects, M3i, Mass, Matrix-Assisted Laser Desorption-Ionization, Protein Structure, Secondary, Sequence Alignment, Sequence Homology, Spectrometry},
pubstate = {published},
tppubtype = {article}
}
By combination of size exclusion and reversed-phase chromatography, we have isolated a novel member of insect defensin-type antimicrobial peptides from the entire bodies of bacteria-challenged Formica rufa (hymenoptera, formicidae). The molecular mass of the purified peptide was estimated to be 4120.42 by matrix-assisted laser desorption/ionization-time of flight/mass spectrometry. Sequence analysis revealed that this peptide consisted of 40 amino acid residues with six cysteines engaged in the formation of three intramolecular disulfide bridges. This peptide is unique among the arthropod defensins in terms of the presence of asparatic acid and alanine at position 33 and as C-terminal residue, respectively. In addition, this novel defensin from Formica rufa has the particularity to have no C-terminal extension in contrast to those reported for other hymenoptera defensins.
Nicolas E, Reichhart Jean-Marc, Hoffmann Jules A, Lemaitre Bruno
In vivo regulation of the IkappaB homologue cactus during the immune response of Drosophila Article de journal
Dans: J. Biol. Chem., vol. 273, no. 17, p. 10463–10469, 1998, ISSN: 0021-9258.
Résumé | BibTeX | Étiquettes: Animals, Cell Surface, DNA-Binding Proteins, Gene Expression Regulation, hoffmann, Insect Proteins, Larva, M3i, Membrane Glycoproteins, Phosphoproteins, Proto-Oncogene Proteins, Receptors, reichhart, Signal Transduction, Toll-Like Receptors, Transcription Factor RelB, Transcription Factors
@article{nicolas_vivo_1998,
title = {In vivo regulation of the IkappaB homologue cactus during the immune response of Drosophila},
author = {E Nicolas and Jean-Marc Reichhart and Jules A Hoffmann and Bruno Lemaitre},
issn = {0021-9258},
year = {1998},
date = {1998-04-01},
journal = {J. Biol. Chem.},
volume = {273},
number = {17},
pages = {10463--10469},
abstract = {The dorsoventral regulatory gene pathway (spätzle/Toll/cactus) controls the expression of several antimicrobial genes during the immune response of Drosophila. This regulatory cascade shows striking similarities with the cytokine-induced activation cascade of NF-kappaB during the inflammatory response in mammals. Here, we have studied the regulation of the IkappaB homologue Cactus in the fat body during the immune response. We observe that the cactus gene is up-regulated in response to immune challenge. Interestingly, the expression of the cactus gene is controlled by the spätzle/Toll/cactus gene pathway, indicating that the cactus gene is autoregulated. We also show that two Cactus isoforms are expressed in the cytoplasm of fat body cells and that they are rapidly degraded and resynthesized after immune challenge. This degradation is also dependent on the Toll signaling pathway. Altogether, our results underline the striking similarities between the regulation of IkappaB and cactus during the immune response.},
keywords = {Animals, Cell Surface, DNA-Binding Proteins, Gene Expression Regulation, hoffmann, Insect Proteins, Larva, M3i, Membrane Glycoproteins, Phosphoproteins, Proto-Oncogene Proteins, Receptors, reichhart, Signal Transduction, Toll-Like Receptors, Transcription Factor RelB, Transcription Factors},
pubstate = {published},
tppubtype = {article}
}
The dorsoventral regulatory gene pathway (spätzle/Toll/cactus) controls the expression of several antimicrobial genes during the immune response of Drosophila. This regulatory cascade shows striking similarities with the cytokine-induced activation cascade of NF-kappaB during the inflammatory response in mammals. Here, we have studied the regulation of the IkappaB homologue Cactus in the fat body during the immune response. We observe that the cactus gene is up-regulated in response to immune challenge. Interestingly, the expression of the cactus gene is controlled by the spätzle/Toll/cactus gene pathway, indicating that the cactus gene is autoregulated. We also show that two Cactus isoforms are expressed in the cytoplasm of fat body cells and that they are rapidly degraded and resynthesized after immune challenge. This degradation is also dependent on the Toll signaling pathway. Altogether, our results underline the striking similarities between the regulation of IkappaB and cactus during the immune response.
Levashina Elena A, Ohresser S, Lemaitre Bruno, Imler Jean-Luc
Two distinct pathways can control expression of the gene encoding the Drosophila antimicrobial peptide metchnikowin Article de journal
Dans: Journal of Molecular Biology, vol. 278, no. 3, p. 515–527, 1998, ISSN: 0022-2836.
Résumé | Liens | BibTeX | Étiquettes: Animals, Anti-Infective Agents, Antimicrobial Cationic Peptides, Base Sequence, Cloning, Gene Expression Regulation, Genes, Genetic, Genetically Modified, Glycopeptides, imler, Insect, Insect Proteins, Larva, M3i, Molecular, Mutation, Peptides, Promoter Regions, Recombinant Fusion Proteins, Reporter, Restriction Mapping, Transcription
@article{levashina_two_1998,
title = {Two distinct pathways can control expression of the gene encoding the Drosophila antimicrobial peptide metchnikowin},
author = {Elena A Levashina and S Ohresser and Bruno Lemaitre and Jean-Luc Imler},
doi = {10.1006/jmbi.1998.1705},
issn = {0022-2836},
year = {1998},
date = {1998-01-01},
journal = {Journal of Molecular Biology},
volume = {278},
number = {3},
pages = {515--527},
abstract = {Metchnikowin is a recently discovered proline-rich peptide from Drosophila with antibacterial and antifungal properties. Like most other antimicrobial peptides from insects, its expression is immune-inducible. Here we present evidence that induction of metchnikowin gene expression can be mediated either by the TOLL pathway or by the imd gene product. We show that the gene remains inducible in Toll-deficient mutants, in which the antifungal response is blocked, as well as in imd mutants, which fail to mount an antibacterial response. However, in Toll-deficient;imd double mutants, metchnikowin gene expression can no longer be detected after immune challenge. Our results suggest that expression of this peptide with dual activity can be triggered by signals generated by either bacterial or fungal infection. Cloning of the metchnikowin gene revealed the presence in the 5' flanking region of several putative cis-regulatory motifs characterized in the promoters of insect immune genes: namely, Rel sites, GATA motifs, interferon consensus response elements and NF-IL6 response elements. Establishment of transgenic fly lines in which the GFP reporter gene was placed under the control of 1.5 kb of metchnikowin gene upstream sequences indicates that this fragment is able to confer full immune inducibility and tissue specificity of expression on the transgene.},
keywords = {Animals, Anti-Infective Agents, Antimicrobial Cationic Peptides, Base Sequence, Cloning, Gene Expression Regulation, Genes, Genetic, Genetically Modified, Glycopeptides, imler, Insect, Insect Proteins, Larva, M3i, Molecular, Mutation, Peptides, Promoter Regions, Recombinant Fusion Proteins, Reporter, Restriction Mapping, Transcription},
pubstate = {published},
tppubtype = {article}
}
Metchnikowin is a recently discovered proline-rich peptide from Drosophila with antibacterial and antifungal properties. Like most other antimicrobial peptides from insects, its expression is immune-inducible. Here we present evidence that induction of metchnikowin gene expression can be mediated either by the TOLL pathway or by the imd gene product. We show that the gene remains inducible in Toll-deficient mutants, in which the antifungal response is blocked, as well as in imd mutants, which fail to mount an antibacterial response. However, in Toll-deficient;imd double mutants, metchnikowin gene expression can no longer be detected after immune challenge. Our results suggest that expression of this peptide with dual activity can be triggered by signals generated by either bacterial or fungal infection. Cloning of the metchnikowin gene revealed the presence in the 5' flanking region of several putative cis-regulatory motifs characterized in the promoters of insect immune genes: namely, Rel sites, GATA motifs, interferon consensus response elements and NF-IL6 response elements. Establishment of transgenic fly lines in which the GFP reporter gene was placed under the control of 1.5 kb of metchnikowin gene upstream sequences indicates that this fragment is able to confer full immune inducibility and tissue specificity of expression on the transgene.
1997
Meister Marie, Lemaitre Bruno, Hoffmann Jules A
Antimicrobial peptide defense in Drosophila Article de journal
Dans: Bioessays, vol. 19, no. 11, p. 1019–1026, 1997, ISSN: 0265-9247.
Résumé | Liens | BibTeX | Étiquettes: Animals, Anti-Infective Agents, Gene Expression Regulation, Genetic, hoffmann, Insect Proteins, M3i, Models, Peptides, Promoter Regions, Signal Transduction
@article{meister_antimicrobial_1997,
title = {Antimicrobial peptide defense in Drosophila},
author = {Marie Meister and Bruno Lemaitre and Jules A Hoffmann},
doi = {10.1002/bies.950191112},
issn = {0265-9247},
year = {1997},
date = {1997-11-01},
journal = {Bioessays},
volume = {19},
number = {11},
pages = {1019--1026},
abstract = {Drosophila responds to a septic injury by the rapid synthesis of antimicrobial peptides. These molecules are predominantly produced by the fat body, a functional equivalent of mammalian liver, and are secreted into the hemolymph where their concentrations can reach up to 100 microM. Six distinct antibacterial peptides (plus isoforms) and one antifungal peptide have been characterized in Drosophila and their genes cloned. The induction of the gene encoding the antifungal peptide relies on the spätzle/Toll/cactus gene cassette, which is involved in the control of dorsoventral patterning in the embryo, and shows interesting structural and functional similarities with cytokine-induced activation of NF-kappa B in mammalian cells. An additional pathway, dependent on the as yet unidentified imd (for immune-deficiency) gene, is required for the full induction of the antibacterial peptide genes. Mutants deficient for the Toll and imd pathways exhibit a severely reduced survival to fungal and bacterial infections, respectively. Recent data on the molecular mechanisms underlying recognition of non-self are also discussed in this review.},
keywords = {Animals, Anti-Infective Agents, Gene Expression Regulation, Genetic, hoffmann, Insect Proteins, M3i, Models, Peptides, Promoter Regions, Signal Transduction},
pubstate = {published},
tppubtype = {article}
}
Drosophila responds to a septic injury by the rapid synthesis of antimicrobial peptides. These molecules are predominantly produced by the fat body, a functional equivalent of mammalian liver, and are secreted into the hemolymph where their concentrations can reach up to 100 microM. Six distinct antibacterial peptides (plus isoforms) and one antifungal peptide have been characterized in Drosophila and their genes cloned. The induction of the gene encoding the antifungal peptide relies on the spätzle/Toll/cactus gene cassette, which is involved in the control of dorsoventral patterning in the embryo, and shows interesting structural and functional similarities with cytokine-induced activation of NF-kappa B in mammalian cells. An additional pathway, dependent on the as yet unidentified imd (for immune-deficiency) gene, is required for the full induction of the antibacterial peptide genes. Mutants deficient for the Toll and imd pathways exhibit a severely reduced survival to fungal and bacterial infections, respectively. Recent data on the molecular mechanisms underlying recognition of non-self are also discussed in this review.
1996
Barillas-Mury Carolina, Charlesworth A, Gross I, Richman A, Hoffmann Jules A, Kafatos Fotis C
Immune factor Gambif1, a new rel family member from the human malaria vector, Anopheles gambiae Article de journal
Dans: EMBO J., vol. 15, no. 17, p. 4691–4701, 1996, ISSN: 0261-4189.
Résumé | BibTeX | Étiquettes: Amino Acid, Animals, Anopheles, Base Sequence, Biological Transport, Cell Nucleus, Cells, Complementary, Cultured, DNA, DNA-Binding Proteins, hoffmann, Insect Proteins, Insect Vectors, M3i, NF-kappa B, Proto-Oncogene Proteins, Proto-Oncogene Proteins c-rel, Sequence Homology, Trans-Activators, Transcriptional Activation
@article{barillas-mury_immune_1996,
title = {Immune factor Gambif1, a new rel family member from the human malaria vector, Anopheles gambiae},
author = {Carolina Barillas-Mury and A Charlesworth and I Gross and A Richman and Jules A Hoffmann and Fotis C Kafatos},
issn = {0261-4189},
year = {1996},
date = {1996-09-01},
journal = {EMBO J.},
volume = {15},
number = {17},
pages = {4691--4701},
abstract = {A novel rel family member, Gambif1 (gambiae immune factor 1), has been cloned from the human malaria vector, Anopheles gambiae, and shown to be most similar to Drosophila Dorsal and Dif. Gambif1 protein is translocated to the nucleus in fat body cells in response to bacterial challenge, although the mRNA is present at low levels at all developmental stages and is not induced by infection. DNA binding activity to the kappaB-like sites in the A.gambiae Defensin and the Drosophila Diptericin and Cecropin promoters is also induced in larval nuclear extracts following infection. Gambif1 has the ability to bind to kappaB-like sites in vitro. Co-transfection assays in Drosophila mbn-2 cells show that Gambif1 can activate transcription by interacting with the Drosophila Diptericin regulatory elements, but is not functionally equivalent to Dorsal in this assay. Gambif1 protein translocation to the nucleus and the appearance of kappaB-like DNA binding activity can serve as molecular markers of activation of the immune system and open up the possibility of studying the role of defence reactions in determining mosquito susceptibility/refractoriness to malaria infection.},
keywords = {Amino Acid, Animals, Anopheles, Base Sequence, Biological Transport, Cell Nucleus, Cells, Complementary, Cultured, DNA, DNA-Binding Proteins, hoffmann, Insect Proteins, Insect Vectors, M3i, NF-kappa B, Proto-Oncogene Proteins, Proto-Oncogene Proteins c-rel, Sequence Homology, Trans-Activators, Transcriptional Activation},
pubstate = {published},
tppubtype = {article}
}
A novel rel family member, Gambif1 (gambiae immune factor 1), has been cloned from the human malaria vector, Anopheles gambiae, and shown to be most similar to Drosophila Dorsal and Dif. Gambif1 protein is translocated to the nucleus in fat body cells in response to bacterial challenge, although the mRNA is present at low levels at all developmental stages and is not induced by infection. DNA binding activity to the kappaB-like sites in the A.gambiae Defensin and the Drosophila Diptericin and Cecropin promoters is also induced in larval nuclear extracts following infection. Gambif1 has the ability to bind to kappaB-like sites in vitro. Co-transfection assays in Drosophila mbn-2 cells show that Gambif1 can activate transcription by interacting with the Drosophila Diptericin regulatory elements, but is not functionally equivalent to Dorsal in this assay. Gambif1 protein translocation to the nucleus and the appearance of kappaB-like DNA binding activity can serve as molecular markers of activation of the immune system and open up the possibility of studying the role of defence reactions in determining mosquito susceptibility/refractoriness to malaria infection.
Gross I, Georgel Philippe, Kappler Christine, Reichhart Jean-Marc, Hoffmann Jules A
Drosophila immunity: a comparative analysis of the Rel proteins dorsal and Dif in the induction of the genes encoding diptericin and cecropin Article de journal
Dans: Nucleic Acids Res., vol. 24, no. 7, p. 1238–1245, 1996, ISSN: 0305-1048.
Résumé | BibTeX | Étiquettes: Animals, Antimicrobial Cationic Peptides, Base Sequence, DNA Primers, DNA-Binding Proteins, Gene Expression Regulation, Genetic, hoffmann, Insect Hormones, Insect Proteins, M3i, NF-kappa B, Nuclear Proteins, Peptides, Phosphoproteins, reichhart, Transcription, Transcription Factors, Transcriptional Activation
@article{gross_drosophila_1996,
title = {Drosophila immunity: a comparative analysis of the Rel proteins dorsal and Dif in the induction of the genes encoding diptericin and cecropin},
author = {I Gross and Philippe Georgel and Christine Kappler and Jean-Marc Reichhart and Jules A Hoffmann},
issn = {0305-1048},
year = {1996},
date = {1996-04-01},
journal = {Nucleic Acids Res.},
volume = {24},
number = {7},
pages = {1238--1245},
abstract = {In Drosophila, bacterial challenge induces the rapid transcription of several genes encoding potent antibacterial peptides. The upstream sequences of the diptericin and cecropin Al genes, which have been investigated in detail, contain two, respectively one sequence element homologous to the binding site of the mammalian nuclear factor kappaB. These elements have been shown to be mandatory for immune-induced transcription of both genes. Functional studies have shown that these kappaB-related elements can be the target for the Drosophila Rel proteins dorsal and Dif. Here we present a comparative analysis of the transactivating capacities of these proteins on reporter genes fused to either the diptericin or the cecropin kappaB-related motifs. We conclude from our results: (i) the kappaB motifs of the diptericin and cecropin genes are not functionally equivalent; (ii) the dorsal and Dif proteins have distinct DNA-binding characteristics; (iii) dorsal and Dif can heterodimerize in vitro; (iv) mutants containing no copies of dorsal and a single copy of Dif retain their full capacity to express the diptericin and cecropin genes in response to challenge.},
keywords = {Animals, Antimicrobial Cationic Peptides, Base Sequence, DNA Primers, DNA-Binding Proteins, Gene Expression Regulation, Genetic, hoffmann, Insect Hormones, Insect Proteins, M3i, NF-kappa B, Nuclear Proteins, Peptides, Phosphoproteins, reichhart, Transcription, Transcription Factors, Transcriptional Activation},
pubstate = {published},
tppubtype = {article}
}
In Drosophila, bacterial challenge induces the rapid transcription of several genes encoding potent antibacterial peptides. The upstream sequences of the diptericin and cecropin Al genes, which have been investigated in detail, contain two, respectively one sequence element homologous to the binding site of the mammalian nuclear factor kappaB. These elements have been shown to be mandatory for immune-induced transcription of both genes. Functional studies have shown that these kappaB-related elements can be the target for the Drosophila Rel proteins dorsal and Dif. Here we present a comparative analysis of the transactivating capacities of these proteins on reporter genes fused to either the diptericin or the cecropin kappaB-related motifs. We conclude from our results: (i) the kappaB motifs of the diptericin and cecropin genes are not functionally equivalent; (ii) the dorsal and Dif proteins have distinct DNA-binding characteristics; (iii) dorsal and Dif can heterodimerize in vitro; (iv) mutants containing no copies of dorsal and a single copy of Dif retain their full capacity to express the diptericin and cecropin genes in response to challenge.
Lemaitre Bruno, Nicolas E, Michaut Lydia, Reichhart Jean-Marc, Hoffmann Jules A
The dorsoventral regulatory gene cassette spätzle/Toll/cactus controls the potent antifungal response in Drosophila adults Article de journal
Dans: Cell, vol. 86, no. 6, p. 973–983, 1996, ISSN: 0092-8674.
Résumé | BibTeX | Étiquettes: Animals, Antifungal Agents, Cell Surface, DNA-Binding Proteins, Fungi, Gene Expression, Genes, hoffmann, Insect, Insect Hormones, Insect Proteins, M3i, Membrane Glycoproteins, MHC Class II, Mutation, Mycoses, NF-kappa B, Phosphoproteins, Proteins, Receptors, reichhart, Signal Transduction, Toll-Like Receptors
@article{lemaitre_dorsoventral_1996,
title = {The dorsoventral regulatory gene cassette spätzle/Toll/cactus controls the potent antifungal response in Drosophila adults},
author = {Bruno Lemaitre and E Nicolas and Lydia Michaut and Jean-Marc Reichhart and Jules A Hoffmann},
issn = {0092-8674},
year = {1996},
date = {1996-01-01},
journal = {Cell},
volume = {86},
number = {6},
pages = {973--983},
abstract = {The cytokine-induced activation cascade of NF-kappaB in mammals and the activation of the morphogen dorsal in Drosophila embryos show striking structural and functional similarities (Toll/IL-1, Cactus/I-kappaB, and dorsal/NF-kappaB). Here we demonstrate that these parallels extend to the immune response of Drosophila. In particular, the intracellular components of the dorsoventral signaling pathway (except for dorsal) and the extracellular Toll ligand, spätzle, control expression of the antifungal peptide gene drosomycin in adults. We also show that mutations in the Toll signaling pathway dramatically reduce survival after fungal infection. Antibacterial genes are induced either by a distinct pathway involving the immune deficiency gene (imd) or by combined activation of both imd and dorsoventral pathways.},
keywords = {Animals, Antifungal Agents, Cell Surface, DNA-Binding Proteins, Fungi, Gene Expression, Genes, hoffmann, Insect, Insect Hormones, Insect Proteins, M3i, Membrane Glycoproteins, MHC Class II, Mutation, Mycoses, NF-kappa B, Phosphoproteins, Proteins, Receptors, reichhart, Signal Transduction, Toll-Like Receptors},
pubstate = {published},
tppubtype = {article}
}
The cytokine-induced activation cascade of NF-kappaB in mammals and the activation of the morphogen dorsal in Drosophila embryos show striking structural and functional similarities (Toll/IL-1, Cactus/I-kappaB, and dorsal/NF-kappaB). Here we demonstrate that these parallels extend to the immune response of Drosophila. In particular, the intracellular components of the dorsoventral signaling pathway (except for dorsal) and the extracellular Toll ligand, spätzle, control expression of the antifungal peptide gene drosomycin in adults. We also show that mutations in the Toll signaling pathway dramatically reduce survival after fungal infection. Antibacterial genes are induced either by a distinct pathway involving the immune deficiency gene (imd) or by combined activation of both imd and dorsoventral pathways.
1995
Lemaitre Bruno, Kromer-Metzger E, Michaut Lydia, Nicolas E, Meister Marie, Georgel Philippe, Reichhart Jean-Marc, Hoffmann Jules A
A recessive mutation, immune deficiency (imd), defines two distinct control pathways in the Drosophila host defense Article de journal
Dans: Proc. Natl. Acad. Sci. U.S.A., vol. 92, no. 21, p. 9465–9469, 1995, ISSN: 0027-8424.
Résumé | BibTeX | Étiquettes: Animals, Anti-Bacterial Agents, Antimicrobial Cationic Peptides, Bacterial Infections, Base Sequence,