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2009 |
Fraiture, Malou; Baxter, Richard H G; Steinert, Stefanie; Chelliah, Yogarany; Frolet, Cécile; Quispe-Tintaya, Wilber; Hoffmann, Jules A; Blandin, Stéphanie A; Levashina, Elena A Two mosquito LRR proteins function as complement control factors in the TEP1-mediated killing of Plasmodium Article de journal Cell Host Microbe, 5 (3), p. 273–284, 2009, ISSN: 1934-6069. Résumé | Liens | BibTeX | Étiquettes: Animals, Anopheles, APL1, Biological, blandin, Complement System Proteins, Hemolymph, hoffmann, Immunologic Factors, LRIM1, M3i, Models, Plasmodium, Protein Binding, Proteins, TEP1 @article{fraiture_two_2009, title = {Two mosquito LRR proteins function as complement control factors in the TEP1-mediated killing of Plasmodium}, author = {Malou Fraiture and Richard H G Baxter and Stefanie Steinert and Yogarany Chelliah and Cécile Frolet and Wilber Quispe-Tintaya and Jules A Hoffmann and Stéphanie A Blandin and Elena A Levashina}, doi = {10.1016/j.chom.2009.01.005}, issn = {1934-6069}, year = {2009}, date = {2009-03-01}, journal = {Cell Host Microbe}, volume = {5}, number = {3}, pages = {273--284}, abstract = {Plasmodium development within Anopheles mosquitoes is a vulnerable step in the parasite transmission cycle, and targeting this step represents a promising strategy for malaria control. The thioester-containing complement-like protein TEP1 and two leucine-rich repeat (LRR) proteins, LRIM1 and APL1, have been identified as major mosquito factors that regulate parasite loads. Here, we show that LRIM1 and APL1 are required for binding of TEP1 to parasites. RNAi silencing of the LRR-encoding genes results in deposition of TEP1 on Anopheles tissues, thereby depleting TEP1 from circulation in the hemolymph and impeding its binding to Plasmodium. LRIM1 and APL1 not only stabilize circulating TEP1, they also stabilize each other prior to their interaction with TEP1. Our results indicate that three major antiparasitic factors in mosquitoes jointly function as a complement-like system in parasite killing, and they reveal a role for LRR proteins as complement control factors.}, keywords = {Animals, Anopheles, APL1, Biological, blandin, Complement System Proteins, Hemolymph, hoffmann, Immunologic Factors, LRIM1, M3i, Models, Plasmodium, Protein Binding, Proteins, TEP1}, pubstate = {published}, tppubtype = {article} } Plasmodium development within Anopheles mosquitoes is a vulnerable step in the parasite transmission cycle, and targeting this step represents a promising strategy for malaria control. The thioester-containing complement-like protein TEP1 and two leucine-rich repeat (LRR) proteins, LRIM1 and APL1, have been identified as major mosquito factors that regulate parasite loads. Here, we show that LRIM1 and APL1 are required for binding of TEP1 to parasites. RNAi silencing of the LRR-encoding genes results in deposition of TEP1 on Anopheles tissues, thereby depleting TEP1 from circulation in the hemolymph and impeding its binding to Plasmodium. LRIM1 and APL1 not only stabilize circulating TEP1, they also stabilize each other prior to their interaction with TEP1. Our results indicate that three major antiparasitic factors in mosquitoes jointly function as a complement-like system in parasite killing, and they reveal a role for LRR proteins as complement control factors. |
2008 |
Goto, Akira; Matsushita, Kazufumi; Gesellchen, Viola; Chamy, Laure El; Kuttenkeuler, David; Takeuchi, Osamu; Hoffmann, Jules A; Akira, Shizuo; Boutros, Michael; Reichhart, Jean-Marc Akirins are highly conserved nuclear proteins required for NF-kappaB-dependent gene expression in drosophila and mice Article de journal Nat. Immunol., 9 (1), p. 97–104, 2008, ISSN: 1529-2916. Résumé | Liens | BibTeX | Étiquettes: Animals, Cell Line, Embryo, Fibroblasts, hoffmann, Humans, Immunity, Innate, Interleukin-1beta, M3i, Mammalian, Mice, NF-kappa B, Nuclear Proteins, Proteins, reichhart, Signal Transduction, Toll-Like Receptors, transgenic, Tumor Necrosis Factor-alpha @article{goto_akirins_2008, title = {Akirins are highly conserved nuclear proteins required for NF-kappaB-dependent gene expression in drosophila and mice}, author = {Akira Goto and Kazufumi Matsushita and Viola Gesellchen and Laure El Chamy and David Kuttenkeuler and Osamu Takeuchi and Jules A Hoffmann and Shizuo Akira and Michael Boutros and Jean-Marc Reichhart}, doi = {10.1038/ni1543}, issn = {1529-2916}, year = {2008}, date = {2008-01-01}, journal = {Nat. Immunol.}, volume = {9}, number = {1}, pages = {97--104}, abstract = {During a genome-wide screen with RNA-mediated interference, we isolated CG8580 as a gene involved in the innate immune response of Drosophila melanogaster. CG8580, which we called Akirin, encoded a protein that acted in parallel with the NF-kappaB transcription factor downstream of the Imd pathway and was required for defense against Gram-negative bacteria. Akirin is highly conserved, and the human genome contains two homologs, one of which was able to rescue the loss-of-function phenotype in drosophila cells. Akirins were strictly localized to the nucleus. Knockout of both Akirin homologs in mice showed that one had an essential function downstream of the Toll-like receptor, tumor necrosis factor and interleukin (IL)-1beta signaling pathways leading to the production of IL-6. Thus, Akirin is a conserved nuclear factor required for innate immune responses.}, keywords = {Animals, Cell Line, Embryo, Fibroblasts, hoffmann, Humans, Immunity, Innate, Interleukin-1beta, M3i, Mammalian, Mice, NF-kappa B, Nuclear Proteins, Proteins, reichhart, Signal Transduction, Toll-Like Receptors, transgenic, Tumor Necrosis Factor-alpha}, pubstate = {published}, tppubtype = {article} } During a genome-wide screen with RNA-mediated interference, we isolated CG8580 as a gene involved in the innate immune response of Drosophila melanogaster. CG8580, which we called Akirin, encoded a protein that acted in parallel with the NF-kappaB transcription factor downstream of the Imd pathway and was required for defense against Gram-negative bacteria. Akirin is highly conserved, and the human genome contains two homologs, one of which was able to rescue the loss-of-function phenotype in drosophila cells. Akirins were strictly localized to the nucleus. Knockout of both Akirin homologs in mice showed that one had an essential function downstream of the Toll-like receptor, tumor necrosis factor and interleukin (IL)-1beta signaling pathways leading to the production of IL-6. Thus, Akirin is a conserved nuclear factor required for innate immune responses. |
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 Proc. Natl. Acad. Sci. U.S.A., 97 (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. |
Rihn, B H; Bottin, M C; Coulais, C; Rouget, R; Monhoven, N; Baranowski, W; Edorh, A; Keith, G Genotoxicity of 3-methylcholanthrene in liver of transgenic big Blue mice Article de journal Environ Mol Mutagen, 36 (4), p. 266-73, 2000, (0893-6692 Journal Article). Résumé | BibTeX | Étiquettes: *Escherichia, Adducts, Animals, Bacterial, Base, C57BL, Cell, coli, Division/drug, DNA, effects, Gov't, Inbred, Liver/cytology/*drug, Methylcholanthrene/*toxicity, Mice, Mutagens/*toxicity, Mutation, Non-U.S., Organ, Primers, Proteins, Proteins/genetics, Repressor, Sequence, Support, transgenic, Weight @article{, title = {Genotoxicity of 3-methylcholanthrene in liver of transgenic big Blue mice}, author = { B. H. Rihn and M. C. Bottin and C. Coulais and R. Rouget and N. Monhoven and W. Baranowski and A. Edorh and G. Keith}, year = {2000}, date = {2000-01-01}, journal = {Environ Mol Mutagen}, volume = {36}, number = {4}, pages = {266-73}, abstract = {Transgenic mice provide a unique tool for studying the tissue specificity and mutagenic potential of chemicals. Because 3-methylcholanthrene (3MC) was found mutagenic in bacteria, clastogenic in bone marrow, and induces DNA adducts in animals, we were interested to determinine whether this xenobiotic provokes (1) cell proliferation, (2) transcriptional activity changes, (3) DNA adducts, and (4) hepatic mutations in transgenic Big Blue mice carrying the lambdaLIZ phage shuttle vector. Big Blue C57/Bl male mice were treated with a single intraperitoneal dose of 80 mg/kg 3MC for 1, 3, 6, 14, or 30 days. Cell proliferation was checked by 5-bromo-2-deoxyuridine labeling and immunohistochemical detection. The maximal increase of the mitotic index was evidenced after 3 days (2.9 times the control value; P < 0.01). The relative nucleus area, reflecting the transcriptional activity, was also the highest in the treated group after 3 days: 1.86 times the control value, on average (P < 0.01). Four major DNA adducts, determined according to the [(32)P]-postlabeling method, were evidenced in liver DNA of treated mice, 6 days after the treatment: the spot intensities increased in a time-dependent manner. The mutant frequency of liver DNA was the highest after 14 days: 20.3 +/- 2.9 x 10(-5) in the treated vs. 7.6 +/- 2.7 x 10(-5) in the control mice (P < 0.01). Sequencing of the lambda lacI mutant plaques showed mainly G:C --> T:A and C:G --> A:T transversions. In conclusion, 3MC at first induced nuclear enlargement and a slight increase of cell proliferation in liver, followed by parallel formation of DNA adducts and mutations. This study shows how transgenic models allow in vivo evaluation of mechanistically simultaneous endpoints.}, note = {0893-6692 Journal Article}, keywords = {*Escherichia, Adducts, Animals, Bacterial, Base, C57BL, Cell, coli, Division/drug, DNA, effects, Gov't, Inbred, Liver/cytology/*drug, Methylcholanthrene/*toxicity, Mice, Mutagens/*toxicity, Mutation, Non-U.S., Organ, Primers, Proteins, Proteins/genetics, Repressor, Sequence, Support, transgenic, Weight}, pubstate = {published}, tppubtype = {article} } Transgenic mice provide a unique tool for studying the tissue specificity and mutagenic potential of chemicals. Because 3-methylcholanthrene (3MC) was found mutagenic in bacteria, clastogenic in bone marrow, and induces DNA adducts in animals, we were interested to determinine whether this xenobiotic provokes (1) cell proliferation, (2) transcriptional activity changes, (3) DNA adducts, and (4) hepatic mutations in transgenic Big Blue mice carrying the lambdaLIZ phage shuttle vector. Big Blue C57/Bl male mice were treated with a single intraperitoneal dose of 80 mg/kg 3MC for 1, 3, 6, 14, or 30 days. Cell proliferation was checked by 5-bromo-2-deoxyuridine labeling and immunohistochemical detection. The maximal increase of the mitotic index was evidenced after 3 days (2.9 times the control value; P < 0.01). The relative nucleus area, reflecting the transcriptional activity, was also the highest in the treated group after 3 days: 1.86 times the control value, on average (P < 0.01). Four major DNA adducts, determined according to the [(32)P]-postlabeling method, were evidenced in liver DNA of treated mice, 6 days after the treatment: the spot intensities increased in a time-dependent manner. The mutant frequency of liver DNA was the highest after 14 days: 20.3 +/- 2.9 x 10(-5) in the treated vs. 7.6 +/- 2.7 x 10(-5) in the control mice (P < 0.01). Sequencing of the lambda lacI mutant plaques showed mainly G:C --> T:A and C:G --> A:T transversions. In conclusion, 3MC at first induced nuclear enlargement and a slight increase of cell proliferation in liver, followed by parallel formation of DNA adducts and mutations. This study shows how transgenic models allow in vivo evaluation of mechanistically simultaneous endpoints. |
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 Biochem. J., 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. |
1999 |
Hoffmann, Jules A; Kafatos, Fotis C; Janeway, Charles A; Ezekowitz, Alan R B Phylogenetic perspectives in innate immunity Article de journal Science, 284 (5418), p. 1313–1318, 1999, ISSN: 0036-8075. Résumé | BibTeX | Étiquettes: Active, Animals, Culicidae, hoffmann, Humans, Immunity, Immunological, infection, Innate, Insect Vectors, M3i, Mammals, Models, Phagocytosis, Phylogeny, Proteins @article{hoffmann_phylogenetic_1999, title = {Phylogenetic perspectives in innate immunity}, author = {Jules A Hoffmann and Fotis C Kafatos and Charles A Janeway and Alan R B Ezekowitz}, issn = {0036-8075}, year = {1999}, date = {1999-05-01}, journal = {Science}, volume = {284}, number = {5418}, pages = {1313--1318}, abstract = {The concept of innate immunity refers to the first-line host defense that serves to limit infection in the early hours after exposure to microorganisms. Recent data have highlighted similarities between pathogen recognition, signaling pathways, and effector mechanisms of innate immunity in Drosophila and mammals, pointing to a common ancestry of these defenses. In addition to its role in the early phase of defense, innate immunity in mammals appears to play a key role in stimulating the subsequent, clonal response of adaptive immunity.}, keywords = {Active, Animals, Culicidae, hoffmann, Humans, Immunity, Immunological, infection, Innate, Insect Vectors, M3i, Mammals, Models, Phagocytosis, Phylogeny, Proteins}, pubstate = {published}, tppubtype = {article} } The concept of innate immunity refers to the first-line host defense that serves to limit infection in the early hours after exposure to microorganisms. Recent data have highlighted similarities between pathogen recognition, signaling pathways, and effector mechanisms of innate immunity in Drosophila and mammals, pointing to a common ancestry of these defenses. In addition to its role in the early phase of defense, innate immunity in mammals appears to play a key role in stimulating the subsequent, clonal response of adaptive immunity. |
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 J. Biol. Chem., 274 (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. |
Lowenberger, C A; Smartt, C T; Bulet, Philippe; Ferdig, M T; Severson, D W; Hoffmann, Jules A; Christensen, B M Insect immunity: molecular cloning, expression, and characterization of cDNAs and genomic DNA encoding three isoforms of insect defensin in Aedes aegypti Article de journal Insect Mol. Biol., 8 (1), p. 107–118, 1999, ISSN: 0962-1075. Résumé | BibTeX | Étiquettes: Aedes, Amino Acid, Animals, Base Sequence, Blotting, Chromosome Mapping, Cloning, Complementary, Defensins, DNA, Gene Expression, Hemolymph, hoffmann, M3i, Molecular, Northern, Protein Isoforms, Proteins, Sequence Homology @article{lowenberger_insect_1999, title = {Insect immunity: molecular cloning, expression, and characterization of cDNAs and genomic DNA encoding three isoforms of insect defensin in Aedes aegypti}, author = {C A Lowenberger and C T Smartt and Philippe Bulet and M T Ferdig and D W Severson and Jules A Hoffmann and B M Christensen}, issn = {0962-1075}, year = {1999}, date = {1999-02-01}, journal = {Insect Mol. Biol.}, volume = {8}, number = {1}, pages = {107--118}, abstract = {Aedes aegypti were immune activated by injection with bacteria, and the expression of insect defensins was measured over time. Northern analyses indicated that defensin transcriptional activity continued for at least 21 days after bacterial injection, and up to 10 days after saline inoculation. Mature defensin levels in the haemolymph reached approximately 45 microM at 24 h post inoculation. cDNAs encoding the preprodefensins of three previously described mature Ae. aegypti defensins were amplified by PCR, cloned and sequenced. Genomic clones were amplified using primers designed against the cDNA sequence. Sequence comparison indicates that there is significant inter- and intra-isoform variability in the signal peptide and prodefensin sequences of defensin genes. Preprodefensin sequences of isoforms A and B are very similar, consisting of a signal peptide region of twenty amino acids, a prodefensin region of thirty-eight amino acids and a forty amino acid mature peptide domain. The sequence encoding isoform C is significantly different, comprising a signal peptide region of twenty-three amino acids, a prodefensin region of thirty-six amino acids, and the mature protein domain of forty amino acids. Analysis of the genomic clones of each isoform revealed one intron spatially conserved in the prodefensin region of all sequences. The intron in isoforms A and B is 64 nt long, and except for a 4 nt substitution in one clone, these intron sequences are identical. The intron in isoform C is 76 nt long and does not share significant identity with the intron sequences of isoforms A or B. The defensin gene mapped to chromosome 3, between two known loci, blt and LF168.}, keywords = {Aedes, Amino Acid, Animals, Base Sequence, Blotting, Chromosome Mapping, Cloning, Complementary, Defensins, DNA, Gene Expression, Hemolymph, hoffmann, M3i, Molecular, Northern, Protein Isoforms, Proteins, Sequence Homology}, pubstate = {published}, tppubtype = {article} } Aedes aegypti were immune activated by injection with bacteria, and the expression of insect defensins was measured over time. Northern analyses indicated that defensin transcriptional activity continued for at least 21 days after bacterial injection, and up to 10 days after saline inoculation. Mature defensin levels in the haemolymph reached approximately 45 microM at 24 h post inoculation. cDNAs encoding the preprodefensins of three previously described mature Ae. aegypti defensins were amplified by PCR, cloned and sequenced. Genomic clones were amplified using primers designed against the cDNA sequence. Sequence comparison indicates that there is significant inter- and intra-isoform variability in the signal peptide and prodefensin sequences of defensin genes. Preprodefensin sequences of isoforms A and B are very similar, consisting of a signal peptide region of twenty amino acids, a prodefensin region of thirty-eight amino acids and a forty amino acid mature peptide domain. The sequence encoding isoform C is significantly different, comprising a signal peptide region of twenty-three amino acids, a prodefensin region of thirty-six amino acids, and the mature protein domain of forty amino acids. Analysis of the genomic clones of each isoform revealed one intron spatially conserved in the prodefensin region of all sequences. The intron in isoforms A and B is 64 nt long, and except for a 4 nt substitution in one clone, these intron sequences are identical. The intron in isoform C is 76 nt long and does not share significant identity with the intron sequences of isoforms A or B. The defensin gene mapped to chromosome 3, between two known loci, blt and LF168. |
Lowenberger, C A; Kamal, S; Chiles, J; Paskewitz, S; Bulet, Philippe; Hoffmann, Jules A; Christensen, B M Mosquito-Plasmodium interactions in response to immune activation of the vector Article de journal Exp. Parasitol., 91 (1), p. 59–69, 1999, ISSN: 0014-4894. Résumé | Liens | BibTeX | Étiquettes: Aedes, Animals, Anopheles, Culicidae, Defensins, Digestive System, Escherichia coli, Female, Genetic, Hemolymph, hoffmann, Insect Vectors, M3i, messenger, Micrococcus luteus, Plasmodium, Plasmodium berghei, Plasmodium gallinaceum, Proteins, Reverse Transcriptase Polymerase Chain Reaction, RNA, Transcription @article{lowenberger_mosquito-plasmodium_1999, title = {Mosquito-Plasmodium interactions in response to immune activation of the vector}, author = {C A Lowenberger and S Kamal and J Chiles and S Paskewitz and Philippe Bulet and Jules A Hoffmann and B M Christensen}, doi = {10.1006/expr.1999.4350}, issn = {0014-4894}, year = {1999}, date = {1999-01-01}, journal = {Exp. Parasitol.}, volume = {91}, number = {1}, pages = {59--69}, abstract = {During the development of Plasmodium sp. within the mosquito midgut, the parasite undergoes a series of developmental changes. The elongated ookinete migrates through the layers of the midgut where it forms the oocyst under the basal lamina. We demonstrate here that if Aedes aegypti or Anopheles gambiae, normally susceptible to Plasmodium gallinaceum and P. berghei, respectively, are immune activated by the injection of bacteria into the hemocoel, and subsequently are fed on an infectious bloodmeal, there is a significant reduction in the prevalence and mean intensity of infection of oocysts on the midgut. Only those mosquitoes immune activated prior to, or immediately after, parasite ingestion exhibit this reduction in parasite development. Mosquitoes immune activated 2-5 days after bloodfeeding show no differences in parasite burdens compared with naive controls. Northern analyses reveal that transcriptional activity for mosquito defensins is not detected in the whole bodies of Ae. aegypti from 4 h to 10 days after ingesting P. gallinaceum, suggesting that parasite ingestion, passage from the food bolus through the midgut, oocyst formation, and subsequent release of sporozoites into the hemolymph do not induce the production of defensin. However, reverse transcriptase-PCR of RNA isolated solely from the midguts of Ae. aegypti indicates that transcription of mosquito defensins occurs in the midguts of naive mosquitoes and those ingesting an infectious or noninfectious bloodmeal. Bacteria-challenged Ae. aegypti showed high levels of mature defensin in the hemolymph that correlate with a lower prevalence and mean intensity of infection with oocysts. Because few oocysts were found on the midgut of immune-activated mosquitoes, the data suggest that some factor, induced by bacterial challenge, kills the parasite at a preoocyst stage.}, keywords = {Aedes, Animals, Anopheles, Culicidae, Defensins, Digestive System, Escherichia coli, Female, Genetic, Hemolymph, hoffmann, Insect Vectors, M3i, messenger, Micrococcus luteus, Plasmodium, Plasmodium berghei, Plasmodium gallinaceum, Proteins, Reverse Transcriptase Polymerase Chain Reaction, RNA, Transcription}, pubstate = {published}, tppubtype = {article} } During the development of Plasmodium sp. within the mosquito midgut, the parasite undergoes a series of developmental changes. The elongated ookinete migrates through the layers of the midgut where it forms the oocyst under the basal lamina. We demonstrate here that if Aedes aegypti or Anopheles gambiae, normally susceptible to Plasmodium gallinaceum and P. berghei, respectively, are immune activated by the injection of bacteria into the hemocoel, and subsequently are fed on an infectious bloodmeal, there is a significant reduction in the prevalence and mean intensity of infection of oocysts on the midgut. Only those mosquitoes immune activated prior to, or immediately after, parasite ingestion exhibit this reduction in parasite development. Mosquitoes immune activated 2-5 days after bloodfeeding show no differences in parasite burdens compared with naive controls. Northern analyses reveal that transcriptional activity for mosquito defensins is not detected in the whole bodies of Ae. aegypti from 4 h to 10 days after ingesting P. gallinaceum, suggesting that parasite ingestion, passage from the food bolus through the midgut, oocyst formation, and subsequent release of sporozoites into the hemolymph do not induce the production of defensin. However, reverse transcriptase-PCR of RNA isolated solely from the midguts of Ae. aegypti indicates that transcription of mosquito defensins occurs in the midguts of naive mosquitoes and those ingesting an infectious or noninfectious bloodmeal. Bacteria-challenged Ae. aegypti showed high levels of mature defensin in the hemolymph that correlate with a lower prevalence and mean intensity of infection with oocysts. Because few oocysts were found on the midgut of immune-activated mosquitoes, the data suggest that some factor, induced by bacterial challenge, kills the parasite at a preoocyst stage. |
1998 |
Gabus, C; Ficheux, D; Rau, M; Keith, G; Sandmeyer, S; Darlix, J L The yeast Ty3 retrotransposon contains a 5'-3' bipartite primer-binding site and encodes nucleocapsid protein NCp9 functionally homologous to HIV-1 NCp7 Article de journal EMBO J, 17 (16), p. 4873-80, 1998, (0261-4189 Journal Article). Résumé | BibTeX | Étiquettes: *Capsid, *Retroelements, Acid, Base, Binding, Capsid/*genetics, cerevisiae/*genetics, dimerization, gag/*genetics, Gene, Gov't, Homology, Met/genetics/*metabolism, Non-U.S., Nucleic, P.H.S., Products, Proteins, RNA, Saccharomyces, Sequence, Sites, Support, Transfer, U.S. @article{, title = {The yeast Ty3 retrotransposon contains a 5'-3' bipartite primer-binding site and encodes nucleocapsid protein NCp9 functionally homologous to HIV-1 NCp7}, author = { C. Gabus and D. Ficheux and M. Rau and G. Keith and S. Sandmeyer and J. L. Darlix}, year = {1998}, date = {1998-01-01}, journal = {EMBO J}, volume = {17}, number = {16}, pages = {4873-80}, abstract = {Retroviruses, including HIV-1 and the distantly related yeast retroelement Ty3, all encode a nucleoprotein required for virion structure and replication. During an in vitro comparison of HIV-1 and Ty3 nucleoprotein function in RNA dimerization and cDNA synthesis, we discovered a bipartite primer-binding site (PBS) for Ty3 composed of sequences located at opposite ends of the genome. Ty3 cDNA synthesis requires the 3' PBS for primer tRNAiMet annealing to the genomic RNA, and the 5' PBS, in cis or in trans, as the reverse transcription start site. Ty3 RNA alone is unable to dimerize, but formation of dimeric tRNAiMet bound to the PBS was found to direct dimerization of Ty3 RNA-tRNAiMet. Interestingly, HIV-1 nucleocapsid protein NCp7 and Ty3 NCp9 were interchangeable using HIV-1 and Ty3 RNA template-primer systems. Our findings impact on the understanding of non-canonical reverse transcription as well as on the use of Ty3 systems to screen for anti-NCp7 drugs.}, note = {0261-4189 Journal Article}, keywords = {*Capsid, *Retroelements, Acid, Base, Binding, Capsid/*genetics, cerevisiae/*genetics, dimerization, gag/*genetics, Gene, Gov't, Homology, Met/genetics/*metabolism, Non-U.S., Nucleic, P.H.S., Products, Proteins, RNA, Saccharomyces, Sequence, Sites, Support, Transfer, U.S.}, pubstate = {published}, tppubtype = {article} } Retroviruses, including HIV-1 and the distantly related yeast retroelement Ty3, all encode a nucleoprotein required for virion structure and replication. During an in vitro comparison of HIV-1 and Ty3 nucleoprotein function in RNA dimerization and cDNA synthesis, we discovered a bipartite primer-binding site (PBS) for Ty3 composed of sequences located at opposite ends of the genome. Ty3 cDNA synthesis requires the 3' PBS for primer tRNAiMet annealing to the genomic RNA, and the 5' PBS, in cis or in trans, as the reverse transcription start site. Ty3 RNA alone is unable to dimerize, but formation of dimeric tRNAiMet bound to the PBS was found to direct dimerization of Ty3 RNA-tRNAiMet. Interestingly, HIV-1 nucleocapsid protein NCp7 and Ty3 NCp9 were interchangeable using HIV-1 and Ty3 RNA template-primer systems. Our findings impact on the understanding of non-canonical reverse transcription as well as on the use of Ty3 systems to screen for anti-NCp7 drugs. |
1996 |
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 Cell, 86 (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. |
1994 |
Fehlbaum, P; Bulet, Philippe; Michaut, L; Lagueux, Marie; Broekaert, W F; Hetru, Charles; Hoffmann, Jules A Insect immunity. Septic injury of Drosophila induces the synthesis of a potent antifungal peptide with sequence homology to plant antifungal peptides Article de journal J. Biol. Chem., 269 (52), p. 33159–33163, 1994, ISSN: 0021-9258. Résumé | BibTeX | Étiquettes: Amino Acid, Animals, Antifungal Agents, Base Sequence, Cloning, Complementary, DNA, hoffmann, Insect Proteins, M3i, Male, messenger, Microbial Sensitivity Tests, Molecular, Peptide Biosynthesis, Peptides, Plants, Protein Biosynthesis, Protein Precursors, Proteins, RNA, Sequence Homology @article{fehlbaum_insect_1994, title = {Insect immunity. Septic injury of Drosophila induces the synthesis of a potent antifungal peptide with sequence homology to plant antifungal peptides}, author = {P Fehlbaum and Philippe Bulet and L Michaut and Marie Lagueux and W F Broekaert and Charles Hetru and Jules A Hoffmann}, issn = {0021-9258}, year = {1994}, date = {1994-12-01}, journal = {J. Biol. Chem.}, volume = {269}, number = {52}, pages = {33159--33163}, abstract = {In response to a septic injury (pricking with a bacteria-soaked needle) larvae and adults of Drosophila produce considerable amounts of a 44-residue peptide containing 8 cysteines engaged in intramolecular disulfide bridges. The peptide is synthesized in the fat body, a functional homologue of the mammalian liver, and secreted into the blood of the insect. It exhibits potent antifungal activity but is inactive against bacteria. This novel inducible peptide, which we propose to name drosomycin, shows a significant homology with a family of 5-kDa cysteine-rich plant antifungal peptides recently isolated from seeds of Brassicaceae. This finding underlines that plants and insects can rely on similar molecules in their innate host defense.}, keywords = {Amino Acid, Animals, Antifungal Agents, Base Sequence, Cloning, Complementary, DNA, hoffmann, Insect Proteins, M3i, Male, messenger, Microbial Sensitivity Tests, Molecular, Peptide Biosynthesis, Peptides, Plants, Protein Biosynthesis, Protein Precursors, Proteins, RNA, Sequence Homology}, pubstate = {published}, tppubtype = {article} } In response to a septic injury (pricking with a bacteria-soaked needle) larvae and adults of Drosophila produce considerable amounts of a 44-residue peptide containing 8 cysteines engaged in intramolecular disulfide bridges. The peptide is synthesized in the fat body, a functional homologue of the mammalian liver, and secreted into the blood of the insect. It exhibits potent antifungal activity but is inactive against bacteria. This novel inducible peptide, which we propose to name drosomycin, shows a significant homology with a family of 5-kDa cysteine-rich plant antifungal peptides recently isolated from seeds of Brassicaceae. This finding underlines that plants and insects can rely on similar molecules in their innate host defense. |
Wilhelm, M L; Reinbolt, J; Gangloff, J; Dirheimer, G; Wilhelm, F X Transfer RNA binding protein in the nucleus of Saccharomyces cerevisiae Article de journal FEBS Lett, 349 (2), p. 260-4, 1994, (0014-5793 Journal Article). Résumé | BibTeX | Étiquettes: *Saccharomyces, &, Acid, Amino, Cell, cerevisiae, cerevisiae/*metabolism, Chromatography, Data, DNA-Binding, DNA/metabolism, Fungal, Fungal/*isolation, high, liquid, Molecular, Nucleus/*metabolism, Pressure, Proteins, Proteins/genetics/*metabolism, purification, RNA, Saccharomyces, Sequence, Transfer/*isolation @article{, title = {Transfer RNA binding protein in the nucleus of Saccharomyces cerevisiae}, author = { M. L. Wilhelm and J. Reinbolt and J. Gangloff and G. Dirheimer and F. X. Wilhelm}, year = {1994}, date = {1994-01-01}, journal = {FEBS Lett}, volume = {349}, number = {2}, pages = {260-4}, abstract = {A yeast nuclear protein that binds to tRNA was identified using a RNA mobility shift assay. Northwestern blotting and N-terminal sequencing experiments indicate that this tRNA-binding protein is identical to zuotin which has previously been shown to bind to Z-DNA [(1992) EMBO J. 11, 3787-3796]. Labeled tRNA and poly(dG-m5dC) stabilized in the Z-DNA form identify the same protein on a Northwestern blot. In a gel retardation assay poly(dG-m5dC) in the Z-form strongly diminishes the binding of tRNA to zuotin. These studies establish that zuotin is able to bind to both tRNA and Z-DNA. Zuotin may be transiently associated with tRNA in the nucleus of yeast cells and play a role in its processing or transport to the cytoplasm.}, note = {0014-5793 Journal Article}, keywords = {*Saccharomyces, &, Acid, Amino, Cell, cerevisiae, cerevisiae/*metabolism, Chromatography, Data, DNA-Binding, DNA/metabolism, Fungal, Fungal/*isolation, high, liquid, Molecular, Nucleus/*metabolism, Pressure, Proteins, Proteins/genetics/*metabolism, purification, RNA, Saccharomyces, Sequence, Transfer/*isolation}, pubstate = {published}, tppubtype = {article} } A yeast nuclear protein that binds to tRNA was identified using a RNA mobility shift assay. Northwestern blotting and N-terminal sequencing experiments indicate that this tRNA-binding protein is identical to zuotin which has previously been shown to bind to Z-DNA [(1992) EMBO J. 11, 3787-3796]. Labeled tRNA and poly(dG-m5dC) stabilized in the Z-DNA form identify the same protein on a Northwestern blot. In a gel retardation assay poly(dG-m5dC) in the Z-form strongly diminishes the binding of tRNA to zuotin. These studies establish that zuotin is able to bind to both tRNA and Z-DNA. Zuotin may be transiently associated with tRNA in the nucleus of yeast cells and play a role in its processing or transport to the cytoplasm. |
1990 |
Hoffmann, Jules A; Hoffmann, Danièle The inducible antibacterial peptides of dipteran insects Article de journal Res. Immunol., 141 (9), p. 910–918, 1990, ISSN: 0923-2494. BibTeX | Étiquettes: Animals, Antimicrobial Cationic Peptides, Defensins, Diptera, Gene Expression Regulation, Genetic, hoffmann, Insect Hormones, Insect Proteins, M3i, Nucleic Acid, Proteins, Sequence Homology, Transcription @article{hoffmann_inducible_1990, title = {The inducible antibacterial peptides of dipteran insects}, author = {Jules A Hoffmann and Danièle Hoffmann}, issn = {0923-2494}, year = {1990}, date = {1990-12-01}, journal = {Res. Immunol.}, volume = {141}, number = {9}, pages = {910--918}, keywords = {Animals, Antimicrobial Cationic Peptides, Defensins, Diptera, Gene Expression Regulation, Genetic, hoffmann, Insect Hormones, Insect Proteins, M3i, Nucleic Acid, Proteins, Sequence Homology, Transcription}, pubstate = {published}, tppubtype = {article} } |