Biologie Digitale de l’ARN

@article{Goto2021,

title = {Verloren negatively regulates the expression of IMD pathway dependent antimicrobial peptides in Drosophila},

author = {Pragya Prakash and Arghyashree Roychowdhury-Sinha and Akira Goto},

url = {https://www.nature.com/articles/s41598-021-94973-0},

doi = {10.1038/s41598-021-94973-0},

year  = {2021},

date = {2021-07-30},

journal = {Scientific Reports},

volume = {11},

number = {15549},

abstract = {Drosophila immune deficiency (IMD) pathway is similar to the human tumor necrosis factor receptor (TNFR) signaling pathway and is preferentially activated by Gram-negative bacterial infection. Recent studies highlighted the importance of IMD pathway regulation as it is tightly controlled by numbers of negative regulators at multiple levels. Here, we report a new negative regulator of the IMD pathway, Verloren (Velo). Silencing of Velo led to constitutive expression of the IMD pathway dependent antimicrobial peptides (AMPs), and Escherichia coli stimulation further enhanced the AMP expression. Epistatic analysis indicated that Velo knock-down mediated AMP upregulation is dependent on the canonical members of the IMD pathway. The immune fluorescent study using overexpression constructs revealed that Velo resides both in the nucleus and cytoplasm, but the majority (~ 75%) is localized in the nucleus. We also observed from in vivo analysis that Velo knock-down flies exhibit significant upregulation of the AMP expression and reduced bacterial load. Survival experiments showed that Velo knock-down flies have a short lifespan and are susceptible to the infection of pathogenic Gram-negative bacteria, P. aeruginosa. Taken together, these data suggest that Velo is an additional new negative regulator of the IMD pathway, possibly acting in both the nucleus and cytoplasm.},

keywords = {bacteria, Biochemistry, DNA, Fungi, Gene Expression, gene regulation, Genetics, hoffmann, Immunochemistry, Immunology, infection, inflammation, Innate immune cells, innate immunity, M3i, microbiology, Molecular Biology, pathogens, RNA, RNAi, Signal Transduction, Transcription},

pubstate = {published},

tppubtype = {article}

}

@article{lee_negative_2011b,

title = {Negative regulation of immune responses on the fly},

author = {Kwang-Zin Lee and Dominique Ferrandon},

doi = {10.1038/emboj.2011.47},

issn = {1460-2075},

year  = {2011},

date = {2011-01-01},

journal = {EMBO J.},

volume = {30},

number = {6},

pages = {988--990},

keywords = {*Gene Expression Regulation, *Homeostasis, Animals, bacteria, Bacteria/*immunology, Biological, Drosophila melanogaster/*immunology, Drosophila Proteins/biosynthesis/metabolism, ferrandon, Gene Expression Regulation, Homeostasis, M3i, Mitogen-Activated Protein Kinases, Mitogen-Activated Protein Kinases/metabolism, Models, NF-kappa B, NF-kappa B/metabolism, ras Proteins, ras Proteins/metabolism, Receptor Protein-Tyrosine Kinases, Receptor Protein-Tyrosine Kinases/metabolism},

pubstate = {published},

tppubtype = {article}

}

@article{hetru_nf-kappab_2009,

title = {NF-kappaB in the immune response of Drosophila},

author = {Charles Hetru and Jules A Hoffmann},

doi = {10.1101/cshperspect.a000232},

issn = {1943-0264},

year  = {2009},

date = {2009-12-01},

journal = {Cold Spring Harb Perspect Biol},

volume = {1},

number = {6},

pages = {a000232},

abstract = {The nuclear factor kappaB (NF-kappaB) pathways play a major role in Drosophila host defense. Two recognition and signaling cascades control this immune response. The Toll pathway is activated by Gram-positive bacteria and by fungi, whereas the immune deficiency (Imd) pathway responds to Gram-negative bacterial infection. The basic mechanisms of recognition of these various types of microbial infections by the adult fly are now globally understood. Even though some elements are missing in the intracellular pathways, numerous proteins and interactions have been identified. In this article, we present a general picture of the immune functions of NF-kappaB in Drosophila with all the partners involved in recognition and in the signaling cascades.},

keywords = {Animals, bacteria, Fungi, Gene Expression Regulation, hoffmann, M3i, NF-kappa B},

pubstate = {published},

tppubtype = {article}

}

@article{flacher_human_2006,

title = {Human Langerhans cells express a specific TLR profile and differentially respond to viruses and Gram-positive bacteria},

author = {Vincent Flacher and Marielle Bouschbacher and Estelle Verronèse and Catherine Massacrier and Vanja Sisirak and Odile Berthier-Vergnes and Blandine de Saint-Vis and Christophe Caux and Colette Dezutter-Dambuyant and Serge Lebecque and Jenny Valladeau},

doi = {10.4049/jimmunol.177.11.7959},

issn = {0022-1767},

year  = {2006},

date = {2006-12-01},

journal = {Journal of Immunology (Baltimore, Md.: 1950)},

volume = {177},

number = {11},

pages = {7959--7967},

abstract = {Dendritic cells (DC) are APCs essential for the development of primary immune responses. In pluristratified epithelia, Langerhans cells (LC) are a critical subset of DC which take up Ags and migrate toward lymph nodes upon inflammatory stimuli. TLR allow detection of pathogen-associated molecular patterns (PAMP) by different DC subsets. The repertoire of TLR expressed by human LC is uncharacterized and their ability to directly respond to PAMP has not been systematically investigated. In this study, we show for the first time that freshly purified LC from human skin express mRNA encoding TLR1, TLR2, TLR3, TLR5, TLR6 and TLR10. In addition, keratinocytes ex vivo display TLR1-5, TLR7, and TLR10. Accordingly, highly enriched immature LC efficiently respond to TLR2 agonists peptidoglycan and lipoteichoic acid from Gram-positive bacteria, and to dsRNA which engages TLR3. In contrast, LC do not directly sense TLR7/8 ligands and LPS from Gram-negative bacteria, which signals through TLR4. TLR engagement also results in cytokine production, with marked differences depending on the PAMP detected. TLR2 and TLR3 ligands increase IL-6 and IL-8 production, while dsRNA alone stimulates TNF-alpha release. Strikingly, only peptidoglycan triggers IL-10 secretion, thereby suggesting a specific function in tolerance to commensal Gram-positive bacteria. However, LC do not produce IL-12p70 or type I IFNs. In conclusion, human LC are equipped with TLR that enable direct detection of PAMP from viruses and Gram-positive bacteria, subsequent phenotypic maturation, and differential cytokine production. This implies a significant role for LC in the control of skin immune responses.},

keywords = {bacteria, Double-Stranded, Gram-Positive Bacteria, Human, Humans, Interleukin-6, Interleukin-8, Langerhans Cells, Reverse Transcriptase Polymerase Chain Reaction, RNA, Skin, Team-Mueller, TLR4, TLR7, Toll-Like Receptors, Tumor Necrosis Factor-alpha, viruses},

pubstate = {published},

tppubtype = {article}

}

@article{durand_lipoteichoic_2006,

title = {Lipoteichoic acid increases TLR and functional chemokine expression while reducing dentin formation in in vitro differentiated human odontoblasts},

author = {Stéphanie H Durand and Vincent Flacher and Annick Roméas and Florence Carrouel and Evelyne Colomb and Claude Vincent and Henry Magloire and Marie-Lise Couble and Françoise Bleicher and Marie-Jeanne Staquet and Serge Lebecque and Jean-Christophe Farges},

doi = {10.4049/jimmunol.176.5.2880},

issn = {0022-1767},

year  = {2006},

date = {2006-03-01},

journal = {Journal of Immunology (Baltimore, Md.: 1950)},

volume = {176},

number = {5},

pages = {2880--2887},

abstract = {Gram-positive bacteria entering the dentinal tissue during the carious process are suspected to influence the immune response in human dental pulp. Odontoblasts situated at the pulp/dentin interface are the first cells encountered by these bacteria and therefore could play a crucial role in this response. In the present study, we found that in vitro-differentiated odontoblasts constitutively expressed the pattern recognition receptor TLR1-6 and 9 genes but not TLR7, 8, and 10. Furthermore, lipoteichoic acid (LTA), a wall component of Gram-positive bacteria, triggered the activation of the odontoblasts. LTA up-regulated the expression of its own receptor TLR2, as well as the production of several chemokines. In particular, an increased amount of CCL2 and CXCL10 was detected in supernatants from LTA-stimulated odontoblasts, and those supernatants augmented the migration of immature dendritic cells in vitro compared with controls. Clinical relevance of these observations came from immunohistochemical analysis showing that CCL2 was expressed in vivo by odontoblasts and blood vessels present under active carious lesions but not in healthy dental pulps. In contrast with this inflammatory response, gene expression of major dentin matrix components (type I collagen, dentin sialophosphoprotein) and TGF-beta1 was sharply down-regulated in odontoblasts by LTA. Taken together, these data suggest that odontoblasts activated through TLR2 by Gram-positive bacteria LTA are able to initiate an innate immune response by secreting chemokines that recruit immature dendritic cells while down-regulating their specialized functions of dentin matrix synthesis and mineralization.},

keywords = {Activation, Analysis, bacteria, Biosynthesis, BLOOD, Blood Vessels, Cell Differentiation, Cells, Chemistry, chemokines, COLLAGEN, Cultured, CXCL10, cytology, Dendritic Cells, DENTAL PULP, Dentin, development, Down-Regulation, Expression, extracellular, EXTRACELLULAR MATRIX, Extracellular Matrix Proteins, function, Gene, Gene Expression, Genes, Genetics, Gram-Positive Bacteria, Human, Humans, IMMATURE, Immunology, IN VITRO, In vivo, Innate immune response, lipopolysaccharide, Lipopolysaccharides, metabolism, migration, Odontoblasts, Organ Culture Techniques, Pharmacology, physiology, PRODUCTION, Protein, Proteins, Receptor, recognition, synthesis, Team-Mueller, Teichoic Acids, TLR7, Toll-Like Receptor 2, Up-Regulation},

pubstate = {published},

tppubtype = {article}

}

@article{bischoff_downregulation_2006,

title = {Downregulation of the Drosophila immune response by peptidoglycan-recognition proteins SC1 and SC2},

author = {Vincent Bischoff and Cécile Vignal and Bernard Duvic and Ivo G Boneca and Jules A Hoffmann and Julien Royet},

doi = {10.1371/journal.ppat.0020014},

issn = {1553-7374},

year  = {2006},

date = {2006-02-01},

journal = {PLoS Pathog.},

volume = {2},

number = {2},

pages = {e14},

abstract = {Peptidoglycan-recognition proteins (PGRPs) are evolutionarily conserved molecules that are structurally related to bacterial amidases. Several Drosophila PGRPs have lost this enzymatic activity and serve as microbe sensors through peptidoglycan recognition. Other PGRP family members, such as Drosophila PGRP-SC1 or mammalian PGRP-L, have conserved the amidase function and are able to cleave peptidoglycan in vitro. However, the contribution of these amidase PGRPs to host defense in vivo has remained elusive so far. Using an RNA-interference approach, we addressed the function of two PGRPs with amidase activity in the Drosophila immune response. We observed that PGRP-SC1/2-depleted flies present a specific over-activation of the IMD (immune deficiency) signaling pathway after bacterial challenge. Our data suggest that these proteins act in the larval gut to prevent activation of this pathway following bacterial ingestion. We further show that a strict control of IMD-pathway activation is essential to prevent bacteria-induced developmental defects and larval death.},

keywords = {Animals, Antimicrobial Cationic Peptides, bacteria, Carrier Proteins, Down-Regulation, hoffmann, Larva, M3i, RNA Interference, Signal Transduction},

pubstate = {published},

tppubtype = {article}

}

@article{thouzeau_spheniscins_2003,

title = {Spheniscins, avian beta-defensins in preserved stomach contents of the king penguin, Aptenodytes patagonicus},

author = {Cécile Thouzeau and Yvon Le Maho and Guillaume Froget and Laurence Sabatier and Céline Le Bohec and Jules A Hoffmann and Philippe Bulet},

doi = {10.1074/jbc.M306839200},

issn = {0021-9258},

year  = {2003},

date = {2003-12-01},

journal = {J. Biol. Chem.},

volume = {278},

number = {51},

pages = {51053--51058},

abstract = {During the last part of egg incubation in king penguins, the male can preserve undigested food in the stomach for several weeks. This ensures survival of the newly hatched chick, in cases where the return of the foraging female from the sea is delayed. In accordance with the characterization of stress-induced bacteria, we demonstrate the occurrence of strong antimicrobial activities in preserved stomach contents. We isolated and fully characterized two isoforms of a novel 38-residue antimicrobial peptide (AMP), spheniscin, belonging to the beta-defensin subfamily. Spheniscin concentration was found to strongly increase during the period of food storage. Using a synthetic version of one of two spheniscin isoforms, we established that this peptide has a broad activity spectrum, affecting the growth of both pathogenic bacteria and fungi. Altogether, our data suggest that spheniscins and other, not yet identified, antimicrobial substances may play a role in the long term preservation of stored food in the stomach of king penguins.},

keywords = {Animals, Antimicrobial Cationic Peptides, bacteria, beta-Defensins, Birds, Feeding Behavior, Fungi, Gastrointestinal Contents, hoffmann, M3i, Male, Mass, Matrix-Assisted Laser Desorption-Ionization, Protein Isoforms, Sequence Alignment, Spectrometry},

pubstate = {published},

tppubtype = {article}

}

@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}

}

@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}

}

@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}

}

@article{hoffmann_immune_1997,

title = {Immune responsiveness in vector insects},

author = {Jules A Hoffmann},

issn = {0027-8424},

year  = {1997},

date = {1997-10-01},

journal = {Proc. Natl. Acad. Sci. U.S.A.},

volume = {94},

number = {21},

pages = {11152--11153},

keywords = {Animals, Anopheles, bacteria, Blood Proteins, Defensins, hoffmann, Humans, Insect Vectors, Life Cycle Stages, M3i, Malaria, Mammals, Plasmodium},

pubstate = {published},

tppubtype = {article}

}

@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 = {Animals, Anti-Bacterial Agents, Antifungal Agents, Antimicrobial Cationic Peptides, bacteria, Base Sequence, Cells, Chromosome Mapping, Cloning, Cultured, Genetic, hoffmann, M3i, Molecular, Peptides, Proline, reichhart, Transcription},

pubstate = {published},

tppubtype = {article}

}

@article{hoffmann_first_1977,

title = {First results of the antibacterial defense reactions of Locusta migratoria larva and imago},

author = {Danièle Hoffmann and M Brehelin and Jules A Hoffmann},

issn = {0003-4150},

year  = {1977},

date = {1977-02-01},

journal = {Ann Parasitol Hum Comp},

volume = {52},

number = {1},

pages = {87--88},

keywords = {Animals, Bacillus thuringiensis, bacteria, Cellular, Grasshoppers, Hematopoietic System, Hemocytes, Hemolymph, hoffmann, Immunity, Larva, M3i, Muramidase},

pubstate = {published},

tppubtype = {article}

}