Consulta: creatorFacets:"Toulza, Eve"
Registros recuperados: 20
Data/hora: 08/06/2024 11:31:56

No pre-zygotic isolation mechanisms between Schistosoma haematobium and Schistosoma bovis parasites: From mating interactions to differential gene expression
Provedor de dados: 5
Autores: Kincaid-smith, Julien; Mathieu-bégné, Eglantine; Chaparro, Cristian; Reguera-gomez, Marta; Mulero, Stephen; Allienne, Jean-francois; Toulza, Eve; Boissier, Jérôme; Lamberton, Poppy H. L.
Species usually develop reproductive isolation mechanisms allowing them to avoid interbreeding. These preventive barriers can act before reproduction, “pre-zygotic barriers”, or after reproduction, “post-zygotic barriers”. Pre-zygotic barriers prevent unfavourable mating, while post-zygotic barriers determine the viability and selective success of the hybrid offspring. Hybridization in parasites and the underlying reproductive isolation mechanisms maintaining their genetic integrity have been overlooked. Using an integrated approach this work aims to quantify the relative importance of pre-zygotic barriers in Schistosoma haematobium x S. bovis crosses. These two co-endemic species cause schistosomiasis, one of the major debilitating parasitic diseases...
Tipo: Text
Ano: 2021
URL: https://archimer.ifremer.fr/doc/00693/80481/83621.pdf

A Novel Bacterial Pathogen of Biomphalaria glabrata: A Potential Weapon for Schistosomiasis Control?
Provedor de dados: 5
Autores: Duval, David; Galinier, Richard; Mouahid, Gabriel; Toulza, Eve; Allienne, Jean Francois; Portela, Julien; Calvayrac, Christophe; Rognon, Anne; Arancibia, Nathalie; Mitta, Guillaume; Theron, Andre; Gourbal, Benjamin.
Background Schistosomiasis is the second-most widespread tropical parasitic disease after malaria. Various research strategies and treatment programs for achieving the objective of eradicating schistosomiasis within a decade have been recommended and supported by the World Health Organization. One of these approaches is based on the control of snail vectors in endemic areas. Previous field studies have shown that competitor or predator introduction can reduce snail numbers, but no systematic investigation has ever been conducted to identify snail microbial pathogens and evaluate their molluscicidal effects. Methodology/Principal findings In populations of Biomphalaria glabrata snails experiencing high mortalities, white nodules were visible on snail...
Tipo: Text
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00615/72716/71712.pdf

Diverging patterns of introgression from Schistosoma bovis across S. haematobium African lineages
Provedor de dados: 5
Autores: Rey, Olivier; Toulza, Eve; Chaparro, Cristian; Allienne, Jean-françois; Kincaid-smith, Julien; Mathieu-begné, Eglantine; Allan, Fiona; Rollinson, David; Webster, Bonnie L.; Boissier, Jérôme.
Hybridization is a fascinating evolutionary phenomenon that raises the question of how species maintain their integrity. Inter-species hybridization occurs between certain Schistosoma species that can cause important public health and veterinary issues. In particular hybrids between Schistosoma haematobium and S. bovis associated with humans and animals respectively are frequently identified in Africa. Recent genomic evidence indicates that some S. haematobium populations show signatures of genomic introgression from S. bovis. Here, we conducted a genomic comparative study and investigated the genomic relationships between S. haematobium, S. bovis and their hybrids using 19 isolates originating from a wide geographical range over Africa, including samples...
Tipo: Text
Ano: 2021
URL: https://archimer.ifremer.fr/doc/00678/79020/81421.pdf

Microbiota Composition and Evenness Predict Survival Rate of Oysters Confronted to Pacific Oyster Mortality Syndrome
Provedor de dados: 5
Autores: Clerissi, Camille; De Lorgeril, Julien; Petton, Bruno; Lucasson, Aude; Escoubas, Jean Michel; Gueguen, Yannick; Dégremont, Lionel; Mitta, Guillaume; Toulza, Eve.
Pacific Oyster Mortality Syndrome (POMS) affects Crassostrea gigas oysters worldwide and causes important economic losses. Disease dynamic was recently deciphered and revealed a multiple and progressive infection caused by the Ostreid herpesvirus OsHV-1 μVar, triggering an immunosuppression followed by microbiota destabilization and bacteraemia by opportunistic bacterial pathogens. However, it remains unknown if microbiota might participate to protect oysters against POMS, and if microbiota characteristics might be predictive of oyster mortalities. To tackle this issue, we transferred full-sib progenies of resistant and susceptible oyster families from hatchery to the field during a period in favor of POMS. After 5 days of transplantation, oysters from...
Tipo: Text
Palavras-chave: Holobiont; Microbiome; Metabarcoding; Fitness; Bacteria.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00621/73332/72500.pdf

A Genome Wide Comparison to Identify Markers to Differentiate the Sex of Larval Stages of Schistosoma haematobium, Schistosoma bovis and their Respective Hybrids
Provedor de dados: 5
Autores: Kincaid-smith, Julien; Boissier, Jerome; Allienne, Jean-francois; Oleaga, Ana; Djuikwo-teukeng, Felicite; Toulza, Eve.
For scientists working on gonochoric organisms, determining sex can be crucial for many biological questions and experimental studies, such as crossbreeding, but it can also be a challenging task, particularly when no sexual dimorphism is visible or cannot be directly observed. In metazoan parasites of the genus Schistosoma responsible for schistosomiasis, sex is genetically determined in the zygote with a female heterogametic ZW/ZZ system. Adult flukes have a pronounced sexual dimorphism, whereas the sexes of the larval stages are morphologically indistinguishable but can be distinguished uniquely by using molecular methods. Therefore, reliable methods are needed to identify the sex of larvae individuals. Here, we present an endpoint PCR-based assay using...
Tipo: Text
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00372/48333/71858.pdf

Protists Within Corals: The Hidden Diversity
Provedor de dados: 5
Autores: Clerissi, Camille; Brunet, Sebastien; Vidal-dupiol, Jeremie; Adjeroud, Mehdi; Lepage, Pierre; Guillou, Laure; Escoubas, Jean Michel; Toulza, Eve.
Previous observations suggested that microbial communities contribute to coral health and the ecological resilience of coral reefs. However, most studies of coral microbiology focused on prokaryotes and the endosymbiotic algae Symbiodinium. In contrast, knowledge concerning diversity of other protists is still lacking, possibly due to methodological constraints. As most eukaryotic DNA in coral samples was derived from hosts, protist diversity was missed in metagenome analyses. To tackle this issue, we designed blocking primers for Scleractinia sequences amplified with two primer sets that targeted variable loops of the 18S rRNA gene (18SV1V2 and 18SV4). These blocking primers were used on environmental colonies of Pocillopora damicornis sensu lato from two...
Tipo: Text
Palavras-chave: Holobiont; Protists; Symbiosis; Metabarcoding; Blocking primer; Scleractinia; Pocillopora damicornis.
Ano: 2018
URL: http://archimer.ifremer.fr/doc/00457/56823/58661.pdf

Metagenomes of the Picoalga Bathycoccus from the Chile Coastal Upwelling
Provedor de dados: 5
Autores: Vaulot, Daniel; Lepere, Cecile; Toulza, Eve; De La Iglesia, Rodrigo; Poulain, Julie; Gaboyer, Frederic; Moreau, Herve; Vandepoele, Klaas; Ulloa, Osvaldo; Gavory, Frederick; Piganeau, Gwenael.
Among small photosynthetic eukaryotes that play a key role in oceanic food webs, picoplanktonic Mamiellophyceae such as Bathycoccus, Micromonas, and Ostreococcus are particularly important in coastal regions. By using a combination of cell sorting by flow cytometry, whole genome amplification (WGA), and 454 pyrosequencing, we obtained metagenomic data for two natural picophytoplankton populations from the coastal upwelling waters off central Chile. About 60% of the reads of each sample could be mapped to the genome of Bathycoccus strain from the Mediterranean Sea (RCC1105), representing a total of 9 Mbp (sample T142) and 13 Mbp (sample T149) of non-redundant Bathycoccus genome sequences. WGA did not amplify all regions uniformly, resulting in unequal...
Tipo: Text
Ano: 2012
URL: http://archimer.ifremer.fr/doc/00129/23987/21945.pdf

Thermal regime and host clade, rather than geography, drive Symbiodinium and bacterial assemblages in the scleractinian coral Pocillopora damicornis sensu lato
Provedor de dados: 5
Autores: Brener-raffalli, Kelly; Clerissi, Camille; Vidal-dupiol, Jeremie; Adjeroud, Mehdi; Bonhomme, Francois; Pratlong, Marine; Aurelle, Didier; Mitta, Guillaume; Toulza, Eve.
Background: Although the term holobiont has been popularized in corals with the advent of the hologenome theory of evolution, the underlying concepts are still a matter of debate. Indeed, the relative contribution of host and environment and especially thermal regime in shaping the microbial communities should be examined carefully to evaluate the potential role of symbionts for holobiont adaptation in the context of global changes. We used the sessile, long-lived, symbiotic and environmentally sensitive reef-building coral Pocillopora damicornis to address these issues. Results: We sampled Pocillopora damicornis colonies corresponding to two different mitochondrial lineages in different geographic areas displaying different thermal regimes: Djibouti,...
Tipo: Text
Palavras-chave: Coral holobiont; Microbiota; Bacterial communities; Symbiodinium assemblages; Thermal adaptation; Scleractinian corals; Coral reefs; Pocillopora damicornis.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00429/54076/55380.pdf

The Pacific Oyster Mortality Syndrome, a Polymicrobial and Multifactorial Disease: State of Knowledge and Future Directions
Provedor de dados: 5
Autores: Petton, Bruno; Destoumieux Garzon, Delphine; Pernet, Fabrice; Toulza, Eve; De Lorgeril, Julien; Degremont, Lionel; Mitta, Guillaume.
The Pacific oyster (Crassostreae gigas) has been introduced from Asia to numerous countries around the world during the 20th century. C. gigas is the main oyster species farmed worldwide and represents more than 98% of oyster production. The severity of disease outbreaks that affect C. gigas, which primarily impact juvenile oysters, has increased dramatically since 2008. The most prevalent disease, Pacific oyster mortality syndrome (POMS), has become panzootic and represents a threat to the oyster industry. Recently, major steps towards understanding POMS have been achieved through integrative molecular approaches. These studies demonstrated that infection by Ostreid herpesvirus type 1 µVar (OsHV-1 µvar) is the first critical step in the infectious process...
Tipo: Text
Palavras-chave: Pacific oyster mortality syndrome; Polymicrobial disease; Multifactorial disease; Crassostrea gigas; OsHV-1; Opportunistic bacterial pathogens.
Ano: 2021
URL: https://archimer.ifremer.fr/doc/00679/79158/81669.pdf

De novo transcriptome assembly for Tracheliastes polycolpus, an invasive ectoparasite of freshwater fish in western Europe
Provedor de dados: 5
Autores: Mathieu-begne, Eglantine; Loot, Geraldine; Blanchet, Simon; Toulza, Eve; Genthon, Clemence; Rey, Olivier.
Tracheliastes polycolpus is an ectoparasitic copepod that recently emerged in western Europe and that infects several freshwater fish species. Its recent successful spread might be due to its fascinating ability to shift to new host populations and/or species. Here, we present the first non-redundant and protein-coding de novo transcriptome assembly for T. polycolpus along with a quality assessment and reliable transcript annotations. This assembly was built from fifteen adult female parasites sampled from three different host species from a single river in southwestern France. Overall, 17,157 non-redundant contigs likely corresponding to protein-coding transcripts were identified, of which 13,093 (i.e., 76%) were successfully annotated. This assembly...
Tipo: Text
Palavras-chave: Copepods; Monoxenous parasite; Parasite specificity; Curation.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00615/72737/75012.pdf

Species-specific mechanisms of cytotoxicity toward immune cells determine the successful outcome of Vibrio infections
Provedor de dados: 5
Autores: Rubio, Tristan; Oyanedel, Daniel; Labreuche, Yannick; Toulza, Eve; Luo, Xing; Bruto, Maxime; Chaparro, Cristian; Torres, Marta; De Lorgeril, Julien; Haffner, Philippe; Vidal-dupiol, Jeremie; Lagorce, Arnaud; Petton, Bruno; Mitta, Guillaume; Jacq, Annick; Le Roux, Frederique; Charriere, Guillaume; Destoumieux-garzon, Delphine.
Vibrio species cause infectious diseases in humans and animals, but they can also live as commensals within their host tissues. How Vibrio subverts the host defenses to mount a successful infection remains poorly understood, and this knowledge is critical for predicting and managing disease. Here, we have investigated the cellular and molecular mechanisms underpinning infection and colonization of 2 virulent Vibrio species in an ecologically relevant host model, oyster, to study interactions with marine Vibrio species. All Vibrio strains were recognized by the immune system, but only nonvirulent strains were controlled. We showed that virulent strains were cytotoxic to hemocytes, oyster immune cells. By analyzing host and bacterial transcriptional...
Tipo: Text
Palavras-chave: T6SS; Toxin; Dual RNA-seq; Cytolysis; Pathogenesis.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00507/61837/65900.pdf

Immune-suppression by OsHV-1 viral infection causes fatal bacteraemia in Pacific oysters
Provedor de dados: 5
Autores: De Lorgeril, Julien; Lucasson, Aude; Petton, Bruno; Toulza, Eve; Montagnani, Caroline; Clerissi, Camille; Vidal-dupiol, Jeremie; Chaparro, Cristian; Galinier, Richard; Escoubas, Jean Michel; Haffner, Philippe; Degremont, Lionel; Charriere, Guillaume; Lafont, Maxime; Delort, Abigail; Vergnes, Agnes; Chiarello, Marlene; Faury, Nicole; Rubio, Tristan; Leroy, Marc; Perignon, Adeline; Regler, Denis; Morga, Benjamin; Alunno-bruscia, Marianne; Boudry, Pierre; Le Roux, Frederique; Destoumieux-garzon, Delphine; Gueguen, Yannick; Mitta, Guillaume.
Infectious diseases are mostly explored using reductionist approaches despite repeated evidence showing them to be strongly in fluenced by numerous interacting host and environmental factors. Many diseases with a complex aetiology therefore remain misunderstood. By developing a holistic approach to tackle the complexity of interactions, we decipher the complex intra-host interactions underlying Pacific oyster mortality syndrome affecting juveniles of Crassostrea gigas, the main oyster species exploited worldwide. Using experimental infections reproducing the natural route of infection and combining thorough molecular analyses of oyster families with contrasted susceptibilities, we demonstrate that the disease is caused by multiple infection with an initial...
Tipo: Text
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00461/57234/59228.pdf

Diversity of quorum sensing autoinducer synthases in the Global Ocean Sampling metagenomic database
Provedor de dados: 5
Autores: Doberva, Margot; Sanchez-ferandin, Sophie; Toulza, Eve; Lebaron, Philippe; Lami, Raphael.
Quorum sensing (QS) is a cell-to-cell signalling pathway that allows bacteria to synchronize their genetic expression. It is mediated by autoinducers (AI), including (1) acyl-homoserine lactones (AHLs or AI-1), produced by Proteobacteria using AinS, LuxI and HdtS synthase families and (2) furanosyl-diester-borate (FDB or AI-2), produced by a large range of phylogenetically diverse bacteria and synthetized by the LuxS family. Few data have been collected about the presence and importance of QS in marine waters using culture independent methods. In this study, we examined the presence and the diversity of AI-1 and AI-2 synthases in the Global Ocean Sampling (GOS), a large metagenomic database, covering 68 stations across 3 oceans. We built 4 reference...
Tipo: Text
Palavras-chave: Quorum sensing; Acyl-homoserine lactone synthases; Global Ocean Sampling; Environmental metagenomes.
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00615/72718/71710.pdf

A community perspective on the concept of marine holobionts: state-of-the-art, challenges, and future directions
Provedor de dados: 5
Autores: Dittami, Simon M; Arboleda, Enrique; Auguet, Jean-christophe; Bigalke, Arite; Briand, Enora; Cardenas, Paco; Cardini, Ulisse; Decelle, Johan; Engelen, Aschwin; Eveillard, Damien; Gachon, Claire Mm; Griffiths, Sarah; Harder, Tilmann; Kayal, Ehsan; Kazamia, Elena; Lallier, François H; Media, Monica; Marzinelli, Ezequiel M; Morganti, Teresa; Nunez Pons, Laura; Prado, Soizik; Pintado, José; Saha, Mahasweta; Selosse, Marc-andré; Skillings, Derek; Stock, Willem; Sunagawa, Shinichi; Toulza, Eve; Vorobev, Alexey; Leblanc, Catherine; Not, Fabrice.
Host-microbe interactions play crucial roles in marine ecosystems, but we still have very little understanding of the mechanisms that govern these relationships, the evolutionary processes that shape them, and their ecological consequences. The holobiont concept is a renewed paradigm in biology that can help describe and understand these complex systems. It posits that a host and its associated microbiota, living together in a long-lasting relationship, form the holobiont, and have to be studied together, as a coherent biological and functional unit, in order to understand the biology, ecology and evolution of the organisms. Here we discuss critical concepts and opportunities in marine holobiont research and identify key challenges in the field. We...
Tipo: Text
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00480/59209/61904.pdf

Malacological survey in a bottle of water: A comparative study between manual sampling and environmental DNA metabarcoding approaches
Provedor de dados: 5
Autores: Mulero, Stephen; Toulza, Eve; Loisier, Anaïs; Zimmerman, Meryl; Allienne, Jean-françois; Foata, Joséphine; Quilichini, Yann; Pointier, Jean-pierre; Rey, Olivier; Boissier, Jérôme.
To assess the effect of anthropogenic activities on ecosystems, it is of prime importance to develop new tools enabling a rapid characterization of ecological communities. Freshwater ecosystems are particularly impacted and threatened by human activities and need thorough attention to preserve their biodiversity and the ecological services they provide. Studying such ecosystems is generally difficult because the associated organisms are hard to sample and to monitor. We present a ready-to-use environmental metabarcoding protocol to characterize and monitor the freshwater gastropods communities from water samples. The efficiency of this new tool was compared to a classical malacological survey at 19 sampled sites from 10 distinct rivers distributed over...
Tipo: Text
Palavras-chave: Biomonitoring; Corsica; Environmental DNA; Malacology; Metabarcoding; Snail communities.
Ano: 2021
URL: https://archimer.ifremer.fr/doc/00666/77777/79917.docx

Schistosomiasis Vector Snails and Their Microbiota Display a Phylosymbiosis Pattern
Provedor de dados: 5
Autores: Huot, Camille; Clerissi, Camille; Gourbal, Benjamin; Galinier, Richard; Duval, David; Toulza, Eve.
Planorbidae snails are the intermediate host for the trematode parasite of the Schistosoma genus, which is responsible for schistosomiasis, a disease that affects both humans and cattle. The microbiota for Schistosoma has already been described as having an effect on host/parasite interactions, specifically through immunological interactions. Here, we sought to characterize the microbiota composition of seven Planorbidae species and strains. Individual snail microbiota was determined using 16S ribosomal DNA amplicon sequencing. The bacterial composition was highly specific to the host strain with limited interindividual variation. In addition, it displayed complete congruence with host phylogeny, revealing a phylosymbiosis pattern. These results were...
Tipo: Text
Palavras-chave: Microbiota; Phylosymbiosis; Metabarcoding; Planorbid snails; Tripartite interactions; Schistosomiasis.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00606/71807/70295.pdf

Microbial iron metabolism as revealed by gene expression profiles in contrasted Southern Ocean regimes
Provedor de dados: 5
Autores: Debeljak, Pavla; Toulza, Eve; Beier, Sara; Blain, Stephane; Obernosterer, Ingrid.
Iron (Fe) is a limiting nutrient in large regions of the ocean, but the strategies of prokaryotes to cope with this micronutrient are poorly known. Using a gene‐specific approach from metatranscriptomics data, we investigated 7 Fe‐related metabolic pathways in microbial communities from High Nutrient Low Chlorophyll and naturally Fe‐fertilized waters in the Southern Ocean. We observed major differences in the contribution of prokaryotic groups at different taxonomic levels to transcripts encoding Fe uptake‐mechanisms, intracellular Fe storage and replacement, and Fe‐related pathways in the tricarboxylic acid (TCA) cycle. The composition of the prokaryotic communities contributing to the transcripts of a given Fe‐related pathway was overall independent of...
Tipo: Text
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00488/59921/63113.eps

Unveiling protist diversity associated with the Pacific oyster Crassostrea gigas using blocking and excluding primers
Provedor de dados: 5
Autores: Clerissi, Camille; Guillou, Laure; Escoubas, Jean Michel; Toulza, Eve.
Background Microbiome of macroorganisms might directly or indirectly influence host development and homeostasis. Many studies focused on the diversity and distribution of prokaryotes within these assemblages, but the eukaryotic microbial compartment remains underexplored so far. Results To tackle this issue, we compared blocking and excluding primers to analyze microeukaryotic communities associated with Crassostrea gigas oysters. High-throughput sequencing of 18S rRNA genes variable loops revealed that excluding primers performed better by not amplifying oyster DNA, whereas the blocking primer did not totally prevent host contaminations. However, blocking and excluding primers showed similar pattern of alpha and beta diversities when protist communities...
Tipo: Text
Palavras-chave: Holobiont; Metabarcoding; Microbiome; Ostreoida; Crassostrea.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00636/74799/75165.pdf

Changements globaux et infections parasitaires à mollusques vecteurs. Un schistosome hybride atteint l’Europe
Provedor de dados: 5
Autores: Boissier, Jerome; Kincaid-smith, Julien; Berry, Antoine; Allienne, Jean-francois; Fillaux, Judith; Toulza, Eve.
Tipo: Text
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00311/42264/71853.pdf

Sex-Biased Transcriptome of Schistosoma mansoni: Host-Parasite Interaction, Genetic Determinants and Epigenetic Regulators Are Associated with Sexual Differentiation
Provedor de dados: 5
Autores: Picard, Marion A. L.; Boissier, Jerome; Roquis, David; Grunau, Christoph; Allienne, Jean-francois; Duval, David; Toulza, Eve; Arancibia, Nathalie; Caffrey, Conor R.; Long, Thavy; Nidelet, Sabine; Rohmer, Marine; Cosseau, Celine.
Background Among more than 20,000 species of hermaphroditic trematodes, Schistosomatidae are unusual since they have evolved gonochorism. In schistosomes, sex is determined by a female heterogametic system, but phenotypic sexual dimorphism appears only after infection of the vertebrate definitive host. The completion of gonad maturation occurs even later, after pairing. To date, the molecular mechanisms that trigger the sexual differentiation in these species remain unknown, and in vivo studies on the developing schistosomulum stages are lacking. To study the molecular basis of sex determination and sexual differentiation in schistosomes, we investigated the whole transcriptome of the human parasite Schistosoma mansoni in a stage-and sex-comparative...
Tipo: Text
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00358/46876/71864.pdf