Publications |

2002
Articles de journaux
8.	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 Science, 297 (5578), p. 114–116, 2002, ISSN: 1095-9203. Résumé \| Liens \| BibTeX \| Étiquettes: Cell Surface, Chromosome Mapping, Escherichia coli, Female, Gene Expression Regulation, Genes, Gram-Positive Cocci, Hemolymph, Hypocreales, Insect, Insect Proteins, Male, Mutation, Protein Sorting Signals, Protein Structure, Receptors, 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 = {Cell Surface, Chromosome Mapping, Escherichia coli, Female, Gene Expression Regulation, Genes, Gram-Positive Cocci, Hemolymph, Hypocreales, Insect, Insect Proteins, Male, Mutation, Protein Sorting Signals, Protein Structure, Receptors, Serine Endopeptidases, Tertiary, Toll-Like Receptors}, pubstate = {published}, tppubtype = {article} } Fermer 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. Fermer doi:10.1126/science.1072391 Fermer
7.	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 Nature Immunology, 3 (1), p. 91–97, 2002, ISSN: 1529-2908. Résumé \| Liens \| BibTeX \| Étiquettes: Adaptor Proteins, Amino Acid, 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, Hypocreales, Immunologic, Insect, Insect Proteins, 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, 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, Hypocreales, Immunologic, Insect, Insect Proteins, 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} } Fermer 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. Fermer doi:10.1038/ni747 Fermer
2001
Articles de journaux
6.	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 Nature, 414 (6865), p. 756–759, 2001, ISSN: 0028-0836. Résumé \| Liens \| BibTeX \| Étiquettes: Amino Acid, Anti-Bacterial Agents, Anti-Infective Agents, Bacillus thuringiensis, Carrier Proteins, Cell Surface, Chromosome Mapping, Enterococcus faecalis, Fungi, Genes, Gram-Positive Bacteria, Hemolymph, Humans, Insect, Insect Proteins, Membrane Glycoproteins, Micrococcus luteus, Mutation, Receptors, 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, Anti-Bacterial Agents, Anti-Infective Agents, Bacillus thuringiensis, Carrier Proteins, Cell Surface, Chromosome Mapping, Enterococcus faecalis, Fungi, Genes, Gram-Positive Bacteria, Hemolymph, Humans, Insect, Insect Proteins, Membrane Glycoproteins, Micrococcus luteus, Mutation, Receptors, Sequence Homology, Toll-Like Receptors}, pubstate = {published}, tppubtype = {article} } Fermer 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. Fermer doi:10.1038/414756a Fermer
5.	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 Proc. Natl. Acad. Sci. U.S.A., 98 (22), p. 12630–12635, 2001, ISSN: 0027-8424. Résumé \| Liens \| BibTeX \| Étiquettes: Anopheles, Anti-Bacterial Agents, Anti-Infective Agents, Base Sequence, Chromosome Mapping, Insect Proteins, Insect Vectors, 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 = {Anopheles, Anti-Bacterial Agents, Anti-Infective Agents, Base Sequence, Chromosome Mapping, Insect Proteins, Insect Vectors, Malaria, Messenger, RNA}, pubstate = {published}, tppubtype = {article} } Fermer 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. Fermer doi:10.1073/pnas.221466798 Fermer
4.	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 Dev. Cell, 1 (4), p. 503–514, 2001, ISSN: 1534-5807. Résumé \| BibTeX \| Étiquettes: Anti-Infective Agents, Apoptosis, Bacterial Infections, Caspases, Chromosome Mapping, Cysteine Proteinase Inhibitors, DNA Damage, Female, Gene Expression, I-kappa B Kinase, Immunocompromised Host, In Situ Nick-End Labeling, Insect Proteins, Male, Mutation, Phenotype, Protein Structure, Protein-Serine-Threonine Kinases, 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 = {Anti-Infective Agents, Apoptosis, Bacterial Infections, Caspases, Chromosome Mapping, Cysteine Proteinase Inhibitors, DNA Damage, Female, Gene Expression, I-kappa B Kinase, Immunocompromised Host, In Situ Nick-End Labeling, Insect Proteins, Male, Mutation, Phenotype, Protein Structure, Protein-Serine-Threonine Kinases, Tertiary}, pubstate = {published}, tppubtype = {article} } Fermer 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. Fermer
1999
Articles de journaux
3.	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, Base Sequence, Blotting, Chromosome Mapping, Cloning, Complementary, Defensins, DNA, Gene Expression, Hemolymph, 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, Base Sequence, Blotting, Chromosome Mapping, Cloning, Complementary, Defensins, DNA, Gene Expression, Hemolymph, Molecular, Northern, Protein Isoforms, Proteins, Sequence Homology}, pubstate = {published}, tppubtype = {article} } Fermer 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. Fermer
1995
Articles de journaux
2.	Levashina, Elena A; Ohresser, S; Bulet, Philippe ; Reichhart, Jean-Marc ; Hetru, Charles ; Hoffmann, Jules A Metchnikowin, a novel immune-inducible proline-rich peptide from Drosophila with antibacterial and antifungal properties Article de journal Eur. J. Biochem., 233 (2), p. 694–700, 1995, ISSN: 0014-2956. Résumé \| BibTeX \| Étiquettes: Anti-Bacterial Agents, Antifungal Agents, Antimicrobial Cationic Peptides, Bacteria, Base Sequence, Cells, Chromosome Mapping, Cloning, Cultured, Genetic, Molecular, Peptides, Proline, Transcription @article{levashina_metchnikowin_1995, title = {Metchnikowin, a novel immune-inducible proline-rich peptide from Drosophila with antibacterial and antifungal properties}, author = { Elena A. Levashina and S. Ohresser and Philippe Bulet and Jean-Marc Reichhart and Charles Hetru and Jules A. Hoffmann}, issn = {0014-2956}, year = {1995}, date = {1995-10-01}, journal = {Eur. J. Biochem.}, volume = {233}, number = {2}, pages = {694--700}, abstract = {One of the characteristics of the host defense of higher insects is the rapid and transient synthesis of a variety of potent antimicrobial peptides. To date, several distinct inducible antimicrobial peptides or peptide families have been totally or partially characterized. We present here the isolation and characterization of a novel 26-residue proline-rich immune-inducible peptide from Drosophila, which exhibits both antibacterial (Gram-positive) and antifungal activities. Peptide sequencing and cDNA cloning indicate the presense of two isoforms in our Drosophila Oregon strain, which differ by one residue (His compared to Arg) as a consequence of a single nucleotide change. The gene, which maps in position 52A1-2 on the right arm of the second chromosome, is expressed in the fat body after immune challenge. The novel peptide, which we propose to name metchnikowin, is a member of a family of proline-rich peptides, and we discuss the possible evolutionary relationships within this family.}, keywords = {Anti-Bacterial Agents, Antifungal Agents, Antimicrobial Cationic Peptides, Bacteria, Base Sequence, Cells, Chromosome Mapping, Cloning, Cultured, Genetic, Molecular, Peptides, Proline, Transcription}, pubstate = {published}, tppubtype = {article} } Fermer One of the characteristics of the host defense of higher insects is the rapid and transient synthesis of a variety of potent antimicrobial peptides. To date, several distinct inducible antimicrobial peptides or peptide families have been totally or partially characterized. We present here the isolation and characterization of a novel 26-residue proline-rich immune-inducible peptide from Drosophila, which exhibits both antibacterial (Gram-positive) and antifungal activities. Peptide sequencing and cDNA cloning indicate the presense of two isoforms in our Drosophila Oregon strain, which differ by one residue (His compared to Arg) as a consequence of a single nucleotide change. The gene, which maps in position 52A1-2 on the right arm of the second chromosome, is expressed in the fat body after immune challenge. The novel peptide, which we propose to name metchnikowin, is a member of a family of proline-rich peptides, and we discuss the possible evolutionary relationships within this family. Fermer
1994
Articles de journaux
1.	Dimarcq, Jean-Luc; Hoffmann, Danièle ; Meister, Marie ; Bulet, Philippe ; Lanot, R; Reichhart, Jean-Marc ; Hoffmann, Jules A Characterization and transcriptional profiles of a Drosophila gene encoding an insect defensin. A study in insect immunity Article de journal Eur. J. Biochem., 221 (1), p. 201–209, 1994, ISSN: 0014-2956. Résumé \| BibTeX \| Étiquettes: Base Sequence, Blood Proteins, Chromosome Mapping, Cloning, Complementary, Defensins, DNA, Gene Expression, Genetic, Gram-Positive Bacteria, Larva, Molecular, Molecular Structure, Nucleic Acid, Protein Precursors, Regulatory Sequences, Transcription @article{dimarcq_characterization_1994, title = {Characterization and transcriptional profiles of a Drosophila gene encoding an insect defensin. A study in insect immunity}, author = { Jean-Luc Dimarcq and Danièle Hoffmann and Marie Meister and Philippe Bulet and R. Lanot and Jean-Marc Reichhart and Jules A. Hoffmann}, issn = {0014-2956}, year = {1994}, date = {1994-04-01}, journal = {Eur. J. Biochem.}, volume = {221}, number = {1}, pages = {201--209}, abstract = {Insect defensins are a family of 4-kDa, cationic, inducible antibacterial peptides which bear six cysteine residues engaged in three intramolecular disulfide bridges. They owe their name to certain sequence similarities with defensins from mammalian neutrophiles and macrophages. We report the characterization of a novel defensin isoform from Drosophila and the cloning of the gene encoding a preprodefensin. The gene, which is intronless and present in a single copy/haploid genome, maps at position 46CD on the right arm of the second chromosome. The analysis of the upstream region of the gene reveals the presence of multiple putative cis-regulatory sequences similar to mammalian regulatory motifs of acute-phase-response genes. Transcriptional profiles indicate that the Drosophila defensin gene is induced by bacterial challenge with acute-phase kinetics. It is also expressed in the absence of immune challenge during metamorphosis. These and other data on the Drosophila defensin gene lead us to suggest that insect and mammalian defensins have evolved independently.}, keywords = {Base Sequence, Blood Proteins, Chromosome Mapping, Cloning, Complementary, Defensins, DNA, Gene Expression, Genetic, Gram-Positive Bacteria, Larva, Molecular, Molecular Structure, Nucleic Acid, Protein Precursors, Regulatory Sequences, Transcription}, pubstate = {published}, tppubtype = {article} } Fermer Insect defensins are a family of 4-kDa, cationic, inducible antibacterial peptides which bear six cysteine residues engaged in three intramolecular disulfide bridges. They owe their name to certain sequence similarities with defensins from mammalian neutrophiles and macrophages. We report the characterization of a novel defensin isoform from Drosophila and the cloning of the gene encoding a preprodefensin. The gene, which is intronless and present in a single copy/haploid genome, maps at position 46CD on the right arm of the second chromosome. The analysis of the upstream region of the gene reveals the presence of multiple putative cis-regulatory sequences similar to mammalian regulatory motifs of acute-phase-response genes. Transcriptional profiles indicate that the Drosophila defensin gene is induced by bacterial challenge with acute-phase kinetics. It is also expressed in the absence of immune challenge during metamorphosis. These and other data on the Drosophila defensin gene lead us to suggest that insect and mammalian defensins have evolved independently. Fermer

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