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ABSTRACT: The parasitization of the mussels Mytilus edulis, M. galloprovincialis , and a natural hybrid of these two species by the bucephalid trematode Prosorhynchus squamatus from the northwestern French coast is being reported. The... more
ABSTRACT: The parasitization of the mussels Mytilus edulis, M. galloprovincialis , and a natural hybrid of these two species by the bucephalid trematode Prosorhynchus squamatus from the northwestern French coast is being reported. The pathology of the infections is described. The principal syndromes include atrophy of host tissues, and hence reduction in market value, and parasitic castration.
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Because of the potentially important role of parasite excretory-secretory (ES) products in regulating intermate relationships and host-parasite interactions, we investigated intraspecific variability of adult ES products from a trematode... more
Because of the potentially important role of parasite excretory-secretory (ES) products in regulating intermate relationships and host-parasite interactions, we investigated intraspecific variability of adult ES products from a trematode species. Adults from 3 geographical isolates of Echinostoma caproni were collected and maintained under in vitro conditions. ES products were collected at 4, 8, and 22 hr of in vitro maintenance. In order to test for interspecific variability, ES products from a different echinostome species (Echinostoma sp.) were collected in a similar way. Major ES polypeptides were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis separation and silver staining. The polypeptide patterns of total ES products appeared very stable in time for each isolate. ES products from Echinostoma sp. showed a distinct polypeptide profile with none of the major bands being shared with the E. caproni isolates. Although polypeptide patterns from the 3 E. caproni isolates shared most major bands, isolate-specific bands could be observed. Two isolates exhibited a band at 85 and 119 kDa, respectively, whereas the third isolate was characterized by the absence of both bands. These results, together with the previously reported role of ES products in molecular signaling raise the question of the importance of intraspecific ES product differences in evolutionary processes such as assortative mating or local host adaptation.
Research Interests: Parasitology, Adaptation, Biology, Medicine, Biological Sciences, and 14 moreTrematoda, Variability, Mice, Parasite, Animals, Host-parasite interactions, Mating, Peptides, Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis, Interspecific competition, Molecular weight, Intraspecific Competition, Biomphalaria, and Cricetinae
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SummaryMACROPHAGE MIGRATION INHIBITORY FACTOR (MIF) is a pleiotropic protein with chemotactic, pro-inflammatory, and growth-promoting activities first discovered in mammals. In parasites, MIF homologs are involved in immune evasion and... more
SummaryMACROPHAGE MIGRATION INHIBITORY FACTOR (MIF) is a pleiotropic protein with chemotactic, pro-inflammatory, and growth-promoting activities first discovered in mammals. In parasites, MIF homologs are involved in immune evasion and pathogenesis. Here, we present the first comprehensive analysis of a MIF protein from the devastating plant pathogen Magnaporthe oryzae (Mo). The fungal genome encodes a single MIF protein (MoMIF1) that, unlike the human homolog, harbors multiple low-complexity regions (LCRs) and is unique to Ascomycota. Following infection, MoMIF1 is expressed in the biotrophic phase of the fungus, and is strongly down-regulated during subsequent necrotrophic growth in leaves and roots. We show that MoMIF1 is secreted during plant infection, affects the production of the mycotoxin tenuazonic acid and inhibits plant cell death. Our results show that MoMIF1 is a novel key regulator of fungal virulence that maintains the balance between biotrophy and necrotrophy during ...
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Human macrophage migration inhibitory factor (MIF) is an atypical chemokine implicated in intercellular signaling and innate immunity. MIF orthologs (MIF/D-DT-like proteins, MDLs) are present throughout the plant kingdom, but remain... more
Human macrophage migration inhibitory factor (MIF) is an atypical chemokine implicated in intercellular signaling and innate immunity. MIF orthologs (MIF/D-DT-like proteins, MDLs) are present throughout the plant kingdom, but remain experimentally unexplored in these organisms. Here, we provide an in planta characterization and functional analysis of the three-member gene/protein MDL family in Arabidopsis thaliana. Subcellular localization experiments indicated a nucleo-cytoplasmic distribution of MDL1 and MDL2, while MDL3 is localized to peroxisomes. Protein–protein interaction assays revealed the in vivo formation of MDL1, MDL2, and MDL3 homo-oligomers, as well as the formation of MDL1-MDL2 hetero-oligomers. Functionally, Arabidopsismdl mutants exhibited a delayed transition from vegetative to reproductive growth (flowering) under long-day conditions, but not in a short-day environment. In addition, mdl mutants were more resistant to colonization by the bacterial pathogen Pseudomonas syringae pv. maculicola. The latter phenotype was compromised by the additional mutation of SALICYLIC ACID INDUCTION DEFICIENT 2 (SID2), a gene implicated in the defense-induced biosynthesis of the key signaling molecule salicylic acid. However, the enhanced antibacterial immunity was not associated with any constitutive or pathogen-induced alterations in the levels of characteristic phytohormones or defense-associated metabolites. Interestingly, bacterial infection triggered relocalization and accumulation of MDL1 and MDL2 at the peripheral lobes of leaf epidermal cells. Collectively, our data indicate redundant functionality and a complex interplay between the three chemokine-like Arabidopsis MDL proteins in the regulation of both developmental and immune-related processes. These insights expand the comparative cross-kingdom analysis of MIF/MDL signaling in human and plant systems.
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Research Interests: Polypeptide and brevet
International audienc
Research Interests: Biology and Immune system
Research Interests: Microbiology, Immunology, Mass Spectrometry, Medical Microbiology, Biology, and 15 moreAntimicrobial Peptides, Innate immunity, Medicine, Embryo, Bacillus thuringiensis, Defensin, Arthropods, Antibacterial activity, Immune system, Eggs, Insect, Candidate Genes, Maternal Effect, Invertebrate Immunity, and attacin
Research Interests: Evolutionary Biology, Immunology, Invertebrates, Biology, Medicine, and 13 moreTranscriptome, Immunity, Animals, Snails, Gene Duplication, Biological evolution, Antimicrobial Cationic Peptides, Bacterial infections, Acute Phase Proteins, Species Specificity, Blood Proteins, Mycoses, and conserved sequence
Research Interests: Biology, Medicine, Biological Sciences, Sequence alignment, Animals, and 12 moreAphids, Herbivory, Immune system, Saliva, Vicia faba, Plant immunity, Amino Acid Sequence, Gene Expression Regulation, Plant Leaves, Molecular Sequence Data, Psychology and Cognitive Sciences, and Medical and Health Sciences
Macrophage Migration Inhibitory Factors (MIF) are pivotal cytokines/chemokines for vertebrate immune systems. MIFs are typically soluble single-domain proteins that are conserved across plant, fungal, protist, and metazoan kingdoms, but... more
Macrophage Migration Inhibitory Factors (MIF) are pivotal cytokines/chemokines for vertebrate immune systems. MIFs are typically soluble single-domain proteins that are conserved across plant, fungal, protist, and metazoan kingdoms, but their functions have not been determined in most phylogenetic groups. Here, we describe an atypical multidomain MIF protein. The marine dinoflagellate Lingulodinium polyedra produces a transmembrane protein with an extra-cytoplasmic MIF domain, which localizes to cell-wall-associated membranes and vesicular bodies. This protein is also present in the membranes of extracellular vesicles accumulating at the secretory pores of the cells. Upon exposure to biotic stress, L. polyedra exhibits reduced expression of the MIF gene and reduced abundance of the surface-associated protein. The presence of LpMIF in the membranes of secreted extracellular vesicles evokes the fascinating possibility that LpMIF may participate in intercellular communication and/or in...
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Macrophage migration inhibitory factors (MIF) are multifunctional proteins regulating major processes in mammals, including activation of innate immune responses. MIF proteins also play a role in innate immunity of invertebrate organisms... more
Macrophage migration inhibitory factors (MIF) are multifunctional proteins regulating major processes in mammals, including activation of innate immune responses. MIF proteins also play a role in innate immunity of invertebrate organisms or serve as virulence factors in parasitic organisms, raising the question of their evolutionary history. We performed a broad survey of MIF presence or absence and evolutionary relationships across 803 species of plants, fungi, protists, and animals, and explored a potential relation with the taxonomic status, the ecology, and the lifestyle of individual species. We show that MIF evolutionary history in eukaryotes is complex, involving probable ancestral duplications, multiple gene losses and recent clade-specific re-duplications. Intriguingly, MIFs seem to be essential and highly conserved with many sites under purifying selection in some kingdoms (e.g., plants), while in other kingdoms they appear more dispensable (e.g., in fungi) or present in s...
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This corrects the article DOI: 10.1038/ncomms15451.
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Biomphalaria snails are instrumental in transmission of the human blood fluke Schistosoma mansoni. With the World Health Organization's goal to eliminate schistosomiasis as a global health problem by 2025, there is now renewed... more
Biomphalaria snails are instrumental in transmission of the human blood fluke Schistosoma mansoni. With the World Health Organization's goal to eliminate schistosomiasis as a global health problem by 2025, there is now renewed emphasis on snail control. Here, we characterize the genome of Biomphalaria glabrata, a lophotrochozoan protostome, and provide timely and important information on snail biology. We describe aspects of phero-perception, stress responses, immune function and regulation of gene expression that support the persistence of B. glabrata in the field and may define this species as a suitable snail host for S. mansoni. We identify several potential targets for developing novel control measures aimed at reducing snail-mediated transmission of schistosomiasis.
Research Interests: Molecular Evolution, Pheromones, Multidisciplinary, Animal communication, Animals, and 10 moreHost-parasite interactions, Molecular Phylogenetics and Evolution, Genome, Fresh water, Schistosoma Mansoni, Proteome, Nature Communications, Gene Expression Regulation, Biomphalaria, and Stress Physiological
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Because of the potentially important role of parasite excretory-secretory (ES) products in regulating intermate relationships and host-parasite interactions, we investigated intraspecific variability of adult ES products from a trematode... more
Because of the potentially important role of parasite excretory-secretory (ES) products in regulating intermate relationships and host-parasite interactions, we investigated intraspecific variability of adult ES products from a trematode species. Adults from 3 geographical isolates of Echinostoma caproni were collected and maintained under in vitro conditions. ES products were collected at 4, 8, and 22 hr of in vitro maintenance. In order to test for interspecific variability, ES products from a different echinostome species (Echinostoma sp.) were collected in a similar way. Major ES polypeptides were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis separation and silver staining. The polypeptide patterns of total ES products appeared very stable in time for each isolate. ES products from Echinostoma sp. showed a distinct polypeptide profile with none of the major bands being shared with the E. caproni isolates. Although polypeptide patterns from the 3 E. caproni isolates shared most major bands, isolate-specific bands could be observed. Two isolates exhibited a band at 85 and 119 kDa, respectively, whereas the third isolate was characterized by the absence of both bands. These results, together with the previously reported role of ES products in molecular signaling raise the question of the importance of intraspecific ES product differences in evolutionary processes such as assortative mating or local host adaptation.
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In this study, we characterized for the first time the complete sequence of a L37a cDNA from a cestode specie: Taenia crassiceps. A phylogenetic analysis of L37a ribosomal proteins from distant animal species is presented and the... more
In this study, we characterized for the first time the complete sequence of a L37a cDNA from a cestode specie: Taenia crassiceps. A phylogenetic analysis of L37a ribosomal proteins from distant animal species is presented and the potential use of such proteins in molecule-based phylogeny is discussed.
Research Interests: Microbiology, Taxonomy, Experimental parasitology, Phylogeny, Sequence alignment, and 15 moreChemotaxonomy, Mice, Parasite, Animals, Ribosomal proteins, Veterinary Sciences, Indexation, Amino Acid Sequence, Base Sequence, Ribosomal Protein, DNA Polymerase, Taenia, Molecular Sequence Data, Nucleotide sequence, and ribonucleic acid
In contrast to the growing knowledge accumulated on plant resistance to pathogens, mechanisms of parasite resistance largely remain to be elucidated in animal species. In the present study we investigated mechanisms underlying... more
In contrast to the growing knowledge accumulated on plant resistance to pathogens, mechanisms of parasite resistance largely remain to be elucidated in animal species. In the present study we investigated mechanisms underlying resistance/susceptibility in the snail-trematode system Biomphalaria glabrata-Echinostoma caproni. In particular, we compared the effect of the parasite excretory-secretory (E-S) products on the defence functions of haemocytes from 2 susceptible and 2 resistant snail strains. In vitro experiments showed that E. caproni E-S products inhibit adhesion and phagocytosis of haemocytes from susceptible snails. A partial biochemical characterization also suggested that the interfering factor(s) is (are) heat-labile glycosylated polypeptides of molecular mass between 10 and 30 kDa. Interestingly, haemocytes from resistant snails remained unaffected by the parasite E-S products, suggesting that a constitutive difference results in their refractoriness to the parasite's immunosuppressive factor(s).
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... snails of the genus Biomphalaria would be considered just another pond snail were it ... to soluble PRRs, Biomphalaria plasma contains other proteins with potential immune activity. For example, hydrolytic/cytolytic enzymes such as... more
... snails of the genus Biomphalaria would be considered just another pond snail were it ... to soluble PRRs, Biomphalaria plasma contains other proteins with potential immune activity. For example, hydrolytic/cytolytic enzymes such as lysozyme, acid phosphatases, or proteinases ...
Research Interests: Microbiology, Immunology, Immune response, Medical Microbiology, Apoptosis, and 15 moreGene expression, Cell line, Humans, Liver, Animals, Hemocytes, Schistosoma Mansoni, Cell Proliferation, Amino Acid Sequence, Recombinant Proteins, Molecular Sequence Data, Macrophage migration inhibitory factor, Biomphalaria, reverse transcriptase polymerase chain reaction, and Cricetinae
ABSTRACT Over the last thirty years, the French production of flat oyster Ostrea edulis dropped from15,000 tons/year to 1,500 tons. Marteilia refringens, a parasite of the flat oyster's digestive gland, is partly responsible for... more
ABSTRACT Over the last thirty years, the French production of flat oyster Ostrea edulis dropped from15,000 tons/year to 1,500 tons. Marteilia refringens, a parasite of the flat oyster's digestive gland, is partly responsible for this drop. The fight against this pathogen agent requires a better knowledge of its parasitic cycle. The main hypothesis is the existence of a heteroxenous cycle, that is to say a cycle involving more than one host. However, for thirty years this or these hosts have not been found, and the cycle of Marteilia refringens remains unknown. Au cours des trente dernières années, la production française d'huître plate Ostrea edulis est passée de 15000 tonnes par an à seulement 1500 tonnes actuellement. Le parasite de la glande digestive de l'huître plate, Marteilia refringens, est en partie responsable de cette chute de production. La lutte contre cet agent pathogène nécessite une meilleure connaissance de son cycle parasitaire. L'hypothèse la plus probable est l'existence d'un cycle hétéroxène c'est à dire faisant intervenir d'autres espèces hôtes. Cependant, pendant 30 ans, ce ou ces hôtes n'ayant pu être mis en évidence, le cycle de Marteilia refringens est resté inconnu.
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Research Interests: Innate immunity, Multidisciplinary, Disease susceptibility, Signal Transduction, Animals, and 9 moreHost-parasite interactions, PLoS one, Hemocytes, Biological markers, Schistosoma Mansoni, Gene expression profiling, Biomphalaria, real time polymerase chain reaction, and reverse transcriptase polymerase chain reaction
Echinostomes rely on a molluskan host to achieve the asexual multiplication phase of larval stages in their complex life cycle. Here we present prominent characteristics of the Biomphalaria-Echinostoma systems and detail recent advances... more
Echinostomes rely on a molluskan host to achieve the asexual multiplication phase of larval stages in their complex life cycle. Here we present prominent characteristics of the Biomphalaria-Echinostoma systems and detail recent advances in our understanding of their molecular interactions. Remarkably, studies using these echinostomes, pathogens with relatively modest medical impact have shed light on important aspects of parasite strategies
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SUMMARYThe genetic control of compatibility between laboratory strains of schistosomes and their snail hosts has been studied intensively since the 1970s. These studies show (1) a bewildering array of genotype-by-genotype... more
SUMMARYThe genetic control of compatibility between laboratory strains of schistosomes and their snail hosts has been studied intensively since the 1970s. These studies show (1) a bewildering array of genotype-by-genotype interactions – compatibility between one pair of strains rarely predicts compatibility with other strains, and (2) evidence for a variety of (sometimes conflicting) genetic mechanisms. Why do we observe such variable and conflicting results? One possibility is that it is partly an artifact of the use of laboratory strains that have been in culture for many years and are often inbred. Here we show that results of compatibility trials between snails and schistosomes – all derived from the same natural population – depend very much on whether one uses laboratory-cultured or field-collected individuals. Explanations include environmental effects of the lab on either host or parasite, and genetic changes in either host or parasite during laboratory culture. One intrigui...