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1. Genomic changes during the evolution of the Coxiella genus along the parasitism-mutualism continuum

Author

Santos-Garcia, Diego, Morel, Olivier, Henri, Hélène, El Filali, Adil, Buysse, Marie, Noël, Valérie, McCoy, Karen D., Gottlieb, Yuval, Klasson, Lisa, Zenner, Lionel, Duron, Olivier, and Vavre, Fabrice

Subjects
Archaeology, CC1-960, Science
Abstract

The Coxiellaceae family is composed of five genera showing lifestyles ranging from free-living to symbiosis. Among them, Coxiella burnetii is a well-known pathogen causing Q fever in humans. This bacterium presents both intracellular (parasitic) and environmental (resistant) forms. Recently, several environmental Coxiella genomes have been reported, among which several have come from intracellular mutualistic symbionts of ticks, termed Coxiella-like endosymbionts. We sequenced two new Coxiella-LE genomes from Dermacentor marginatus (CLEDm) and Ornithodoros maritimus (CLEOmar) ticks, the latter belonging to the C. burnetii lineage. Using these newly sequenced Coxiella-LEs and 43 Coxiellaceae genomes, we conducted comparative genomic and phylogenomic analyses to increase our knowledge of C. burnetii pathogenicity and the emergence of Coxiella-LEs. Results highlight the probably parasitic nature of the common ancestor of the Coxiellaceae. Indeed, the virulence factor Dot/Icm T4 Secretion System is present in most, but not all, Coxiellaceae. Whereas it is part of a putative pathogenic island in C. burnetii, it has been entirely lost or inactivated in Coxiella-LEs, suggesting its importance in pathogenesis. Additionally, we found that a Sha/Mrp antiporter was laterally acquired in the C. burnetii lineage. This antiporter might be involved in alkali resistance and the development of the resistant form that is able to persist in the environment for long periods of time. The Sha operon is eroded or absent in Coxiella-LEs. Finally, we found that all Coxiella representatives produce B vitamins and co-factors indicating a pre-adaptation of Coxiella to mutualism with hematophagous arthropods. Accordingly, the ancestor of C. burnetii and Coxiella-LEs was likely a parasitic bacterium able to manipulate its host cell and to produce vitamins and co-factors for its own use.

Published
2023
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2. Analyses of symbiotic bacterial communities in the plant pest Bemisia tabaci reveal high prevalence of Candidatus Hemipteriphilus asiaticus on the African continent

Author

Mouton, Laurence, Henri, Hélène, Romba, Rahim, Belgaidi, Zainab, Gnankiné, Olivier, and Vavre, Fabrice

Subjects
Archaeology, CC1-960, Science
Abstract

Microbial symbionts are widespread in insects and some of them have been associated with adaptive changes. Primary symbionts (P-symbionts) have a nutritional role that allows their hosts to feed on unbalanced diets (plant sap, wood, blood). Most of them have undergone genome reduction, but their genomes still retain genes involved in pathways that are necessary to synthesize the nutrients that their hosts need. However, in some P-symbionts, essential pathways are incomplete and secondary symbionts (S-symbionts) are required to complete parts of their degenerated functions. The P-symbiont of the phloem sap-feeder Bemisia tabaci, Candidatus Portiera aleyrodidarium, lacks genes involved in the synthesis of vitamins, cofactors, and also of some essential amino-acids. Seven S-symbionts have been detected in the B. tabaci species complex. Phenotypic and genomic analyses have revealed various effects, from reproductive manipulation to fitness benefits, notably some of them have complementary metabolic capabilities to Candidatus Portiera aleyrodidarium, suggesting that their presence may be obligatory. In order to get the full picture of the symbiotic community of this pest, we investigated, through metabarcoding approaches, the symbiont content of individuals from Burkina Faso, a West African country where B. tabaci induces severe crop damage. While no new putative B. tabaci S-symbiont was identified, Candidatus Hemipteriphilus asiaticus, a symbiont only described in B. tabaci populations from Asia, was detected for the first time on this continent. Phylogenetic analyses however reveal that it is a different strain than the reference found in Asia. Specific diagnostic PCRs showed a high prevalence of these S-symbionts and especially of Candidatus Hemipteriphilus asiaticus in different genetic groups. These results suggest that Candidatus Hemipteriphilus asiaticus may affect the biology of B. tabaci and provide fitness advantage in some B. tabaci populations.

Published
2022
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3. Wolbachia load variation in Drosophila is more likely caused by drift than by host genetic factors

Author

Bénard, Alexis, Henri, Hélène, Noûs, Camille, Vavre, Fabrice, and Kremer, Natacha

Subjects
Archaeology, CC1-960, Science
Abstract

Symbiosis is a continuum of long-term interactions ranging from mutualism to parasitism, according to the balance between costs and benefits for the protagonists. The density of endosymbionts is, in both cases, a key factor that determines both the transmission of symbionts and the host extended phenotype, and is thus tightly regulated within hosts. However, the evolutionary and molecular mechanisms underlying bacterial density regulation are currently poorly understood. In this context, the symbiosis between the fruit fly and its intracellular bacteria Wolbachia (wMelPop strain) is particularly interesting to study. Although vertically transmitted, the symbiont is pathogenic, and a positive correlation between virulence and wMelPop density is observed. In addition, the number of repeats of a bacterial genomic region -Octomom- is positively correlated with Wolbachia density, underlying a potential genetic mechanism that controls bacterial density. Interestingly, the number of repeats varies between host individuals, but most likely also within them. Such genetic heterogeneity within the host could promote conflicts between bacteria themselves and with the host, notably by increasing within-host competition between symbiont genotypes through a process analogous to the tragedy of the commons. To characterize the determinisms at play in the regulation of bacterial density, we first introgressed wMelPop in different genetic backgrounds of D. melanogaster, and found different density levels and Octomom copy numbers in each host lineage. To determine whether such variations reflect a host genetic determinism on density regulation through Octomom copy number selection, we replicated the introgressions and performed reciprocal crosses on the two Drosophila populations with the most extreme density levels. In both experiments, we detected an absence of directionality in the patterns of infection, associated with a strong instability of these patterns across generations. Given that bacterial density was highly correlated with Octomom copy numbers in all experiments, these results rather suggest a strong influence of drift and a random increase in the frequency of certain bacterial variants. We then discuss how drift, both on the symbiont population during transmission and on the host population, could limit the efficiency of selection in such a symbiotic system, and the consequences of drift on the regulation of density and composition of bacterial populations.

Published
2021
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4. Experimental evolution of virulence and associated traits in a Drosophila melanogaster–Wolbachia symbiosis

Author

Monnin, David, Kremer, Natacha, Michaud, Caroline, Villa, Manon, Henri, Hélène, Desouhant, Emmanuel, and Vavre, Fabrice

Subjects
Archaeology, CC1-960, Science
Abstract

Evolutionary theory predicts that vertically transmitted symbionts are selected for low virulence, as their fitness is directly correlated to that of their host. In contrast with this prediction, the Wolbachia strain wMelPop drastically reduces its Drosophila melanogaster host lifespan at high rearing temperatures. It is generally assumed that this feature is maintained because the D. melanogaster-wMelPop symbiosis is usually not exposed to environmental conditions in which the symbiont is virulent. To test this hypothesis, we submitted wMelPop-infected D. melanogaster lines to 17 generations of experimental evolution at a high temperature, while enforcing late reproduction by artificial selection. The fly survival was measured at different time points, as well as two traits that have been proposed to be causally responsible for wMelPop virulence: its relative density and the mean number of copies of octomom, an 8-genes region of the Wolbachia genome. We hypothesised that these conditions (high temperature and late reproduction) would select for a reduced wMelPop virulence, a reduced wMelPop density, and a reduced octomom copy number. Our results indicate that density, octomom copy number and virulence are correlated to each other. However, contrary to our expectations, we could not detect any reduction in virulence during the course of evolution. We discuss the significance of our results with respect to the evolutionary causes of wMelPop virulence.

Published
2021
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13. Population genomics of Corsican wildcats: Paving the way toward a new subspecies within the Felis silvestris spp. complex?

Author

Portanier, Elodie, Henri, Hélène, Benedetti, Pierre, Sanchis, Frédéric, Régis, Corinne, Chevret, Pascale, Zedda, Marco, El Filali, Adil, Ruette, Sandrine, and Devillard, Sébastien

Subjects
*CATS, *FELIS, *FELIDAE, *GENOMICS, *SUBSPECIES
Abstract

In the context of the current extinction crisis, identifying new conservation units is pivotal to the development of sound conservation measures, especially in highly threatened taxa such as felids. Corsican wildcats are known by Corsican people since a very long time but have been little studied. Meaningful information about their phylogenetic position is lacking. We used ddRADseq to genotype phenotypically homogenous Corsican wildcats at 3671 genome‐wide SNPs and reported for the first time their genetic identity. We compared this genomic information to domestic cats Felis silvestris catus from Corsica and mainland France, European wildcats F. s. silvestris and Sardinian wildcats F. s. lybica. Our premise was that if the Corsican wildcat, as a phenotypic entity, also represents a genetic entity, it deserves conservation measures and to be recognized as a conservation unit. Corsican wildcats appeared highly genetically differentiated from European wildcats and genetically closer to Sardinian wildcats than to domestic cats. Domestic cats from Corsica and mainland France were closer to each other and Sardinian wildcats were intermediate between Corsican wildcats and domestic cats. This suggested that Corsican wildcats do not belong to the F. s. silvestris or catus lineages. The inclusion of more high‐quality Sardinian samples and Near‐Eastern mainland F. s. lybica would constitute the next step toward assessing the status of Corsican wildcat as a subspecies and/or evolutionarily significant unit and tracing back wildcat introduction history of in Corsica. [ABSTRACT FROM AUTHOR]

Published
2023
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16. Targeting RNA:Protein Interactions with an Integrative Approach Leads to the Identification of Potent YB-1 Inhibitors

Author

El Hage, Krystel, primary, Babault, Nicolas, additional, Maciejak, Olek, additional, Desforges, Bénédicte, additional, Craveur, Pierrick, additional, Steiner, Emilie, additional, Rengifo-Gonzalez, Juan Carlos, additional, Henri, Hélène, additional, Clement, Marie-Jeanne, additional, Joshi, Vandana, additional, Bouhss, Ahmed, additional, Wang, Liya, additional, Bauvais, Cyril, additional, and Pastré, David, additional

Published
2022
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17. Influence of bacterial symbionts on host niche and ecological diversification: an integrative approach in a whitefly model

Author

Benhamou, Sylvain, Rahioui, Isabelle, Henri, Hélène, da Silva, Pedro, Charles, Hubert, Heddi, Abdelaziz, Vavre, Fabrice, Desouhant, Emmanuel, Calevro, Federica, Mouton, Laurence, Charles, Hubert, Biologie Fonctionnelle, Insectes et Interactions (BF2I), Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS), Evolution, adaptation et comportement, Département écologie évolutive [LBBE], Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Génétique et évolution des interactions hôtes-parasites, and Département génétique, interactions et évolution des génomes [LBBE] (GINSENG)

Subjects
[SDV] Life Sciences [q-bio], [SDV]Life Sciences [q-bio], insect symbiosis
Abstract

International audience

Published
2022

18. Guardian Symbionts - Disentangling the multitrophic interactions of the supervector Bemisia tabaci

Author

Santos-Garcia, Diego, Henri, Hélène, Belgaidi, Zainab, Urbino, Cica, Peterschmitt, Michel, and Vavre, Fabrice

Abstract

The rising global population puts constant pressure on food production and intensive agricultural practices. Alongside the injudicious use of insecticides, this has modified agrarian ecosystems, causing more plant vectorborne viral diseases than ever before. The EU-funded GuardSym project will focus on the whitefly Bemisia tabaci, one of the worst pest insects, as a vector to investigate its multitrophic interactions with its bacterial symbionts, vectored virus, and host plants. The project will form the basis for the development of population modification strategies where natural populations are replaced with virus-resistant ones that can no longer cause plant disease.

Published
2022

20. Influence of secondary symbionts on host plant utilization and selection in the whitefly Bemisia tabaci

Author

Benhamou, Sylvain, Rahioui, Isabelle, Henri, Hélène, Belgaidi, Zainab, Charles, Hubert, da Silva, Pedro, Heddi, Abdelaziz, Vavre, Fabrice, Desouhant, Emmanuel, Calevro, Federica, Mouton, Laurence, Biologie Fonctionnelle, Insectes et Interactions (BF2I), Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS), Centre de biophysique moléculaire (CBM), Université d'Orléans (UO)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), An algorithmic view on genomes, cells, and environments (BAMBOO), Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS), Génétique et évolution des interactions hôtes-parasites, Département génétique, interactions et évolution des génomes [LBBE] (GINSENG), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Evolution, adaptation et comportement, Département écologie évolutive [LBBE], and Charles, Hubert

Subjects
[SDE] Environmental Sciences, [SDV] Life Sciences [q-bio], secondary symbionts, [SDV]Life Sciences [q-bio], [SDE]Environmental Sciences, insect symbiosis, metabolism
Abstract

International audience

Published
2021

22. Influence of Wolbachia on host gene expression in an obligatory symbiosis

Author

Kremer Natacha, Charif Delphine, Henri Hélène, Gavory Frédérick, Wincker Patrick, Mavingui Patrick, and Vavre Fabrice

Subjects
Microbiology, QR1-502
Abstract

Abstract Background Wolbachia are intracellular bacteria known to be facultative reproductive parasites of numerous arthropod hosts. Apart from these reproductive manipulations, recent findings indicate that Wolbachia may also modify the host’s physiology, notably its immune function. In the parasitoid wasp, Asobara tabida, Wolbachia is necessary for oogenesis completion, and aposymbiotic females are unable to produce viable offspring. The absence of egg production is also associated with an increase in programmed cell death in the ovaries of aposymbiotic females, suggesting that a mechanism that ensures the maintenance of Wolbachia in the wasp could also be responsible for this dependence. In order to decipher the general mechanisms underlying host-Wolbachia interactions and the origin of the dependence, we developed transcriptomic approaches to compare gene expression in symbiotic and aposymbiotic individuals. Results As no genetic data were available on A. tabida, we constructed several Expressed Sequence Tags (EST) libraries, and obtained 12,551 unigenes from this species. Gene expression was compared between symbiotic and aposymbiotic ovaries through in silico analysis and in vitro subtraction (SSH). As pleiotropic functions involved in immunity and development could play a major role in the establishment of dependence, the expression of genes involved in oogenesis, programmed cell death (PCD) and immunity (broad sense) was analyzed by quantitative RT-PCR. We showed that Wolbachia might interfere with these numerous biological processes, in particular some related to oxidative stress regulation. We also showed that Wolbachia may interact with immune gene expression to ensure its persistence within the host. Conclusions This study allowed us to constitute the first major dataset of the transcriptome of A. tabida, a species that is a model system for both host/Wolbachia and host/parasitoid interactions. More specifically, our results highlighted that symbiont infection may interfere with numerous pivotal processes at the individual level, suggesting that the impact of Wolbachia should also be investigated beyond reproductive manipulations.

Published
2012
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23. Evidence of diversity and recombination in Arsenophonus symbionts of the Bemisia tabaci species complex

Author

Mouton Laurence, Thierry Magali, Henri Hélène, Baudin Rémy, Gnankine Olivier, Reynaud Bernard, Zchori-Fein Einat, Becker Nathalie, Fleury Frédéric, and Delatte Hélène

Subjects
Microbiology, QR1-502
Abstract

Abstract Background Maternally inherited bacterial symbionts infecting arthropods have major implications on host ecology and evolution. Among them, the genus Arsenophonus is particularly characterized by a large host spectrum and a wide range of symbiotic relationships (from mutualism to parasitism), making it a good model to study the evolution of host-symbiont associations. However, few data are available on the diversity and distribution of Arsenophonus within host lineages. Here, we propose a survey on Arsenophonus diversity in whitefly species (Hemiptera), in particular the Bemisia tabaci species complex. This polyphagous insect pest is composed of genetic groups that differ in many ecological aspects. They harbor specific bacterial communities, among them several lineages of Arsenophonus, enabling a study of the evolutionary history of these bacteria at a fine host taxonomic level, in association to host geographical range and ecology. Results Among 152 individuals, our analysis identified 19 allelic profiles and 6 phylogenetic groups, demonstrating this bacterium's high diversity. These groups, based on Arsenophonus phylogeny, correlated with B. tabaci genetic groups with two exceptions reflecting horizontal transfers. None of three genes analyzed provided evidence of intragenic recombination, but intergenic recombination events were detected. A mutation inducing a STOP codon on one gene in a strain infecting one B. tabaci genetic group was also found. Phylogenetic analyses of the three concatenated loci revealed the existence of two clades of Arsenophonus. One, composed of strains found in other Hemiptera, could be the ancestral clade in whiteflies. The other, which regroups strains found in Hymenoptera and Diptera, may have been acquired more recently by whiteflies through lateral transfers. Conclusions This analysis of the genus Arsenophonus revealed a diversity within the B. tabaci species complex which resembles that reported on the larger scale of insect taxonomy. We also provide evidence for recombination events within the Arsenophonus genome and horizontal transmission of strains among insect taxa. This work provides further insight into the evolution of the Arsenophonus genome, the infection dynamics of this bacterium and its influence on its insect host's ecology.

Published
2012
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31. Neurodevelopmental Outcomes after Premedication with Atropine/Propofol vs Atropine/Atracurium/Sufentanil for Neonatal Intubation: 2-Year Follow-Up of a Randomized Clinical Trial

Author

Decobert Fabrice, Bloom Marie-Claude, Savey Baptiste, Renault Anais, Olivier Claris, Alix Antoine, Moussa Yasser, Lacour Sandrine, Dassieu Gilles, Blanc Sébastien, Razafimanantsoa Lucie, Planchenault Déborah, Guillemin Marie-Gabrielle, Eyvrard Frédéric, Laetitia Marchand-Martin, Pladys Patrick, Cra Toure Judith, Ramay Isabelle, Auriol Françoise, Cudel Muriel, Guillois Bernard, Romeo Bernard, Clamadieu Catherine, Leport Mathilde, Caeymaex Laurence, Roullet Nicolas, Panici Maud, Cottin Xavier, Cohen Robert, Marcoux Marie-Odile, Vedrenne-Cloquet Meryl, Manon Tauzin, Mus Marianne, Dorriere Valérie, Decock-Giraudaud Aliette, Agnès Dechartres, Gaillot Théophile, Bouamari Hocine, Chauvel Jennifer, Danan Claude, Noseda Céline, Lelong Sandrine, Millot Estelle, Bechet Stéphane, Cénéric Alexandre, Cantagrel Sylvain, Ramadan GhostineGhida, Delahaye Séverine, Bacher Marjorie, Lamour Anne-Marie, Pelluau Sonia, Beissel Anne, Bouissou Antoine, Delaunay Mickaël, Jurado Camille, Cra, Younes Bouthaina, Popov Isabelle, Bruschet Lydie, Pinto Da Costa Nathalina, Prudon Malika, Crosse Julien, Merlot Elodie, eToulouse: Alberge Corinne, Jourdan Diane, Bourgoin Laura, Cornaton Elise, Chantreuil Julie, Chazal Christèle, Dassy Audrey, Henri Hélène, Lallemant Carine, Camille Jung, Sophie Breinig, Barcat Lucile, Peluchon Anne, Leke André, Plaisant Franck, Breant Valentine, Berthomieu Lionel, Beuchee Alain, Prieur Claire, Tirel Olivier, Amadieu Romain, Boddaert Sophie, Saliba Elie, Deniau Anne-Laure, Boucherat Michel, Azcona Barbara, Corinne Levy, Adamon Latif, Labarthe François, Rots Delphine, Meteier Véronique, Fontaine Cécile, Lebas Fanny, Bellemin Karine, Boiron Emilie, Arberet Camille, Moreau François, Ratsimbazafy Lanto, Gauthier-Moulinier Hélène, Pierre Tourneux, Brussieux Maxime, Bouafif Firas, Gaba Mabel, Carpentier Eléonore, Dahan Sonia, Layouni Inès, Xavier Durrmeyer, Sauret Anne, Perez Thierry, Degorre Coralie, Kongolo Guy, Thomas de La Pintiere Armelle, Le Gouez Morgane, Norbert Karine, Ozanne Bruno, Alexandre Mélanie, Tellai Leila, Issa Amelle, Gineste Martine, Bellot Anne, Suc Anne-Laure, An Chu Huu Kim, Kieffer Isabelle, Goudjil Sabrina, Caron-Lesenechal Evelyne, Ghyselen Laurent, Trentesaux Anne-Sophie, and Cécile Lebeaux

Subjects
Atropine, Male, Time Factors, Sufentanil, medicine.medical_treatment, Nervous System, law.invention, 03 medical and health sciences, 0302 clinical medicine, Double-Blind Method, Randomized controlled trial, law, 030225 pediatrics, Intubation, Intratracheal, Humans, Medicine, Intubation, 030212 general & internal medicine, Propofol, business.industry, Tracheal intubation, Significant difference, Infant, Newborn, Anesthetics, Combined, Treatment Outcome, Child, Preschool, Anesthesia, Pediatrics, Perinatology and Child Health, Atracurium, Female, Premedication, business, Adjuvants, Anesthesia, Follow-Up Studies, medicine.drug
Abstract

This study followed 173 newborn infants in the PREmedication Trial for Tracheal Intubation of the NEOnate multicenter, double-blind, randomized controlled trial of atropine-propofol vs atropine-atracurium-sufentanil for premedication before nonemergency intubation. At 2 years of corrected age, there was no significant difference between the groups in death or risk of neurodevelopmental delay assessed with the Ages and Stages Questionnaire. Trial registration Clinicaltrials.gov : NCT01490580 .

Published
2021

33. Does host socio-spatial behavior lead to a fine-scale spatial genetic structure in its associated parasites?

Author

Portanier, Elodie, primary, Garel, Mathieu, additional, Devillard, Sébastien, additional, Duhayer, Jeanne, additional, Poirel, Marie-Thérèse, additional, Henri, Hélène, additional, Régis, Corinne, additional, Maillard, Daniel, additional, Redman, Elizabeth, additional, Itty, Christian, additional, Michel, Patricia, additional, and Bourgoin, Gilles, additional

Published
2019
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34. Species tree, frequent HGT and gene conversions in Bdelloid Rotifers

Author

Cariou, Marie, Henri, Hélène, Debortoli, Nicolas, Terwagne, Matthieu, Hespeels, Boris, Virgo, Julie, De Vienne, Damien, and Van Doninck, Karine

Subjects
phylogenetics, Bdelloid rotifers, sex evolution
Abstract

The vast majority of animals reproduce sexually, i.e. with recombination of genetic material between generations. This genetic mixing is thought to favor the persistence of sexual lineages despite a theoretical advantage of asexuals regarding colonization capacity and population growth. In this context Bdelloid Rotifers, a highly diversified group of animals evolving asexually for millions of years, appears as a puzzle but also as an outstanding model to better understand long-term evolution in the absence of sexual reproduction.The sequencing of the first Bdelloid Rotifer genome (Flot et al. 2013) revealed a peculiar organization, characterized by a degenerate tetraploidy, numerous rearrangements and the absence of homologous chromosomes. This structure, incompatible with meiosis, likely testifies the long asexual evolution of this genome. Besides, population genetic studies suggest that Bdelloids might exchange DNA within and between species, which likely plays a major role in their evolutionary history (Debortoli et al. 2016).To better understand the dynamics of gene conversion and horizontal genetic transfers on these asexually evolving genomes and their importance in the success of Bdelloids, we are generating genomic data (RAD sequencing) from a large number of species distributed across the four existing families. We will show how methods involving the reconciliation of gene and species trees can help resolving species phylogeny of Bdelloids despite asexuality, polyploidy, gene conversions, transfers and losses. The resolution of the species tree is indeed a requirement for further study of the dynamics of horizontal transfers, which might play a key role in their evolution.

Published
2017

37. Two Host Clades, Two Bacterial Arsenals: Evolution through Gene Losses in Facultative Endosymbionts

Author

Rollat-Farnier, Pierre-Antoine, Santos-Garcia, Diego, Rao, Qiong, Sagot, Marie-France, Silva, Francisco J, Henri, Hélène, Zchori-Fein, Einat, Latorre, Amparo, Moya, Andrés, Barbe, Valérie, Liu, Shu-Sheng, Wang, Xiao-Wei, Vavre, Fabrice, Mouton, Laurence, Baobab, Département PEGASE [LBBE] (PEGASE), Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS), An algorithmic view on genomes, cells, and environments (BAMBOO), Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université de Lyon-Université de Lyon-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS), Institut Cavanilles de Biodiversitat i Biologia Evolutiva (ICBiBE), Universitat de València (UV), Zhejiang Agriculture and Forestry University, Equipe de recherche européenne en algorithmique et biologie formelle et expérimentale (ERABLE), Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Agricultural Research Organisation (ARO), Volcani Center, Institut de Génomique d'Evry (IG), Université Paris-Saclay-Institut de Biologie François JACOB (JACOB), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Génétique et évolution des interactions hôtes-parasites, Département génétique, interactions et évolution des génomes [LBBE] (GINSENG), and European Project: 247073,EC:FP7:ERC,ERC-2009-AdG,SISYPHE(2010)

Subjects
Hamiltonella defensa, Virulence Factors, [SDV]Life Sciences [q-bio], fungi, food and beverages, Genomics, comparative genomics, biochemical phenomena, metabolism, and nutrition, Bemisia tabaci, Evolution, Molecular, Hemiptera, aphids, Enterobacteriaceae, Cell Wall, Animals, [INFO.INFO-BI]Computer Science [cs]/Bioinformatics [q-bio.QM], Symbiosis, Gene Deletion, Genome, Bacterial, Phylogeny, Research Article
Abstract

International audience; Bacterial endosymbiosis is an important evolutionary process in insects, which can harbor both obligate and facultative symbionts. The evolution of these symbionts is driven by evolutionary convergence, and they exhibit among the tiniest genomes in prokaryotes. The large host spectrum of facultative symbionts and the high diversity of strategies they use to infect new hosts probably impact the evolution of their genome and explain why they undergo less severe genomic erosion than obligate symbionts. Candidatus Hamiltonella defensa is suitable for the investigation of the genomic evolution of facultative symbionts because the bacteria are engaged in specific relationships in two clades of insects. In aphids, H. defensa is found in several species with an intermediate prevalence and confers protection against parasitoids. In whiteflies, H. defensa is almost fixed in some species of Bemisia tabaci, which suggests an important role of and a transition toward obligate symbiosis. In this study, comparisons of the genome of H. defensa present in two B. tabaci species (Middle East Asia Minor 1 and Mediterranean) and in the aphid Acyrthosiphon pisum revealed that they belong to two distinct clades and underwent specific gene losses. In aphids, it contains highly virulent factors that could allow protection and horizontal transfers. In whiteflies, the genome lost these factors and seems to have a limited ability to acquire genes. However it contains genes that could be involved in the production of essential nutrients, which is consistent with a primordial role for this symbiont. In conclusion, although both lineages of H. defensa have mutualistic interactions with their hosts, their genomes follow distinct evolutionary trajectories that reflect their phenotype and could have important consequences on their evolvability.

Published
2015

38. Phenotypic plasticity in the invasive pest Drosophila suzukii: activity rhythms and gene expression in response to temperature.

Author

Plantamp, Christophe, Henri, Hélène, Andrieux, Thibault, Régis, Corinne, Mialdea, Gladys, Dray, Stéphane, Gibert, Patricia, and Desouhant, Emmanuel

Subjects
*DROSOPHILA suzukii, *PHENOTYPIC plasticity, *GENE expression, *CLOCK genes, *INTRODUCED species, *CIRCADIAN rhythms
Abstract

Phenotypic plasticitymay contribute to the invasive success of an alien species in a new environment. A highly plastic species may survive and reproduce in more diverse environments, thereby supporting establishment and colonization. We focused on plasticity in the circadian rhythm of activity, which can favour species coexistence in invasion, for the invasive species Drosophila suzukii, which is expected to be a weaker direct competitor than other Drosophila species of the resident community. We compared the circadian rhythms of the locomotor activity in adults and the expression of clock genes in response to temperature in the invasive D. suzukii and the resident Drosophila melanogaster.We showed that D. suzukii is active in a narrower range of temperatures than D. melanogaster and that the activities of the two species overlap during the day, regardless of the temperature. Both species are diurnal and exhibit rhythmic activity at dawn and dusk, with a much lower activity at dawn for D. suzukii females. Our results show that the timeless and clock genes are good candidates to explain the plastic response that is observed in relation to temperature. Overall, our results suggest that thermal phenotypic plasticity in D. suzukii activity is not sufficient to explain the invasive success of D. suzukii and call for testing other hypotheses, such as the release of competitors and/or predators. [ABSTRACT FROM AUTHOR]

Published
2019
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39. Host plant specialization matters in the epidemiology of Wolbachia across phytophagous wasps (Hymenoptera: Torymidae)

Author

Boivin, Thomas, Henri, Hélène, Vavre, Fabrice, Gidoin, Cindy, Veber, Philippe, Candau, Jean-Noël, Roques, Alain, Auger-Rozenberg, Marie-Anne, Ecologie des Forêts Méditerranéennes (URFM), Institut National de la Recherche Agronomique (INRA), Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS), Génétique et évolution des interactions hôtes-parasites, Département génétique, interactions et évolution des génomes [LBBE] (GINSENG), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), National Resources Canada, Great Lakes Forestry Ctr, Canadian Forest Service, Unité de recherche Zoologie Forestière (URZF), Projet innovant INRA EFPA, Ecologie des Forêts Méditerranéennes [Avignon] (URFM 629), and Unité de recherche Zoologie Forestière (UZF)

Subjects
spécialisation écologique, parthenogenetic development, Environmental and Society, multilocus sequence typing, [SDE.ES]Environmental Sciences/Environmental and Society, thelytoky, Analyse de séquance multilocus (MLSA), parthenogenesis, ecological specialization, megastigmus, parthénogénèse, thelytoquie, Environnement et Société
Abstract

Host plant specialization matters in the epidemiology of Wolbachia across phytophagous wasps (Hymenoptera: Torymidae). 8. International Wolbachia Conference

Published
2014

40. Host plant specialization influences the spread of endosymbiotic parthenogenesis in seed wasps (Hymenoptera: Torymidae)

Author

Boivin, Thomas, Henri, Hélène, Favre, Fabrice, Gidoin, Cindy, Veber, Philippe, Candau, Jean-Noël, Roques, Alain, Auger-Rozenberg, Marie-Anne, Ecologie des Forêts Méditerranéennes (URFM), Institut National de la Recherche Agronomique (INRA), Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS), Canadian Forest Service, Natural Resources Canada (NRCan), and Unité de recherche Zoologie Forestière (URZF)

Subjects
spécialisation écologique, Biodiversité et Ecologie, [SDE.MCG]Environmental Sciences/Global Changes, interaction hôte symbiote, biological invasion, torymidae, phylogeny, thelytoky, Biodiversity and Ecology, megastigmus, parthénogénèse, thelytoquie, phylogénie, population dynamics, host-symbiont interactions, parthenogenesis, Milieux et Changements globaux, Endosymbiotic bacteria, ComputingMilieux_MISCELLANEOUS, wolbachia, ecological specialization, epidemiology, bactérie endosymbiotique, dynamique des populations, épidémiologie, invasion biologique, hymenoptera, [SDE.BE]Environmental Sciences/Biodiversity and Ecology
Abstract

International audience

Published
2014

42. Distribution of Bemisia tabaci (Homoptera: Aleyrodidae) biotypes and their associated symbiotic bacteria on host plants in West Africa

Author

Gnankine, Olivier, Mouton, Laurence, Henri, Hélène, Terraz, Gabriel, Houndete, Thomas, Martin, Thibaud, Vavre, Fabrice, Fleury, Frédéric, Université Joseph Ki-Zerbo [Ouagadougou] (UJZK), Génétique et évolution des interactions hôtes-parasites, Département génétique, interactions et évolution des génomes [LBBE] (GINSENG), Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS), Fonctionnement agroécologique et performances des systèmes de cultures horticoles (UPR HORTSYS), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), An algorithmic view on genomes, cells, and environments (BAMBOO), Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), and Université de Lyon-Université de Lyon-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Plante hôte, Distribution géographique, Symbiose, Distribution des populations, Bemisia tabaci, host plant, secondary symbionts, Biotype, parasitic diseases, West Africa, Dynamique des populations, Bacteria, H10 - Ravageurs des plantes, biotypes, Plante de culture, [SDV.EE.IEO]Life Sciences [q-bio]/Ecology, environment/Symbiosis
Abstract

International audience; 1. The whitefly Bemisia tabaci is a pest of many agricultural and ornamental crops worldwide and particularly in Africa. B. tabaci is a complex of more than 20 biotypes. Effective control of B. tabaci calls for a greater knowledge of the local biological diversity in terms of biotypes or putative species. Information is available about biotype distribution in Northern, Eastern, and Southern Africa, but data for Western Africa remain very scarce. At the time of this study, data were available for only three sampling sites in Burkina Faso, where three biotypes have been detected, the native Sub-Saharan Africa non-Silver Leafing (AnSL), the Sub-Saharan Africa Silverleafing (ASL), and the Mediterranean Q biotypes, but no information is available about their respective distributions on host plant species (Gueguen et al., 2010). 2. Our study describes the biotypes and symbiotic bacterial communities of B. tab-aci sampled in three West African countries, Burkina Faso, Benin, and Togo. A total of 527 individuals were collected from seven cultivated host plants. 3. In the 20 localities studied, we found the same three biotypes AnSL, ASL, and Q previously detected in Burkina Faso. These biotypes display a specific pattern of geographical distribution influenced by the host plant species. In Benin and Togo, the ASL and AnSL biotypes were predominant, while in Burkina Faso, the Q bio-type was dominant, with two subgroups , Q1 and Q3 (recorded to date only in this country), and ASL individuals found in sympatry with Q1 individuals in some localities. As previously reported, each biotype and each genetic group harbours a specific community of symbiotic bacteria.

Published
2013

43. Development of a PCR‐RFLP assay to identify Drosophila melanogaster among field‐collected larvae.

Author

Raquin, Vincent, Henri, Hélène, Vallat, Marine, Leulier, François, Gibert, Patricia, and Kremer, Natacha

Subjects
*POLYMERASE chain reaction, *RESTRICTION fragment length polymorphisms, *DROSOPHILA melanogaster, *CYTOCHROME oxidase genetics, *LARVAL microbiology
Abstract

The fruit fly Drosophila melanogaster is a model organism to study several aspects of metazoan biology. Most of the work has been conducted in adult fruit flies, including laboratory and field‐derived specimens, but Drosophila melanogaster larvae recently became a valuable model to better understand animal physiology, development, or host–microbe interactions. While adult flies can be easily assigned to a given Drosophila species based on morphological characteristics, such visual identification is more intricate at the larval stage. This could explain the limited number of studies focusing on larvae, especially field‐derived samples. Here, we developed a polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) assay that discriminates D. melanogaster from other ecologically relevant Drosophila species at the larval stage. The method, which targets the cytochrome oxidase I (COI) gene, was validated using laboratory‐derived larvae from seven D. melanogaster populations originating from different geographic areas as well as six Drosophila species. We further validated this PCR‐RFLP assay in a natural context, by identifying wild larvae collected in two locations in France. Notably, among all PCR‐RFLP profiles that matched the D. melanogaster species, 100% were correctly identified, as confirmed by COI sequencing. In summary, our work provides a rapid, simple, and accurate molecular tool to identify D. melanogaster from field‐collected larvae. Invertebrates species, like the fruit fly Drosophila melanogaster, are widely used in biology. However, taxonomic identification remains complicated especially at the larval stage. Our work provides a rapid, cost‐effective, and accurate tool to identify Drosophila melanogaster species validated using field‐collected larvae. [ABSTRACT FROM AUTHOR]

Published
2018
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44. Occurrence of arrhenotoky and thelytoky in a parasitic wasp Venturia canescens(Hymenoptera: Ichneumonidae): Effect of endosymbionts or existence of twodistinct reproductive modes?

Author

Foray, Vincent, Henri, Hélène, Martinez, Sonia, Gibert, Patricia, Desouhant, Emmanuel, Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS), Génétique et évolution des interactions hôtes-parasites, Département génétique, interactions et évolution des génomes [LBBE] (GINSENG), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Evolution, adaptation et comportement, and Département écologie évolutive [LBBE]

Subjects
[SDV.GEN.GPO]Life Sciences [q-bio]/Genetics/Populations and Evolution [q-bio.PE], [SDE.MCG]Environmental Sciences/Global Changes, [SDV.BID.EVO]Life Sciences [q-bio]/Biodiversity/Populations and Evolution [q-bio.PE], [SDV.SA.AGRO]Life Sciences [q-bio]/Agricultural sciences/Agronomy, [SDV.MP.PAR]Life Sciences [q-bio]/Microbiology and Parasitology/Parasitology, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, ComputingMilieux_MISCELLANEOUS, [SDV.EE.IEO]Life Sciences [q-bio]/Ecology, environment/Symbiosis
Abstract

International audience

Published
2013

45. Local adaptation and evolution of parasitoid interactions in an invasive species, Drosophila subobscura

Author

Gibert, P., Allemand, Roland, Henri, Hélène, Huey, R.B., Génétique et évolution des interactions hôtes-parasites, Département génétique, interactions et évolution des génomes [LBBE] (GINSENG), Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), and Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDV.EE]Life Sciences [q-bio]/Ecology, environment, [SDV]Life Sciences [q-bio], fungi, ComputingMilieux_MISCELLANEOUS
Abstract

International audience; Background: About 30 years ago, the Palaearctic fly Drosophila subobscura successfully invaded the New World, where parasitoid species diversity was thought to be lower than in the Old World. Hypotheses: Because parasitoids cause major mortality to Drosophila, the invader should benefit from escaping its natural parasitoid enemies and enjoy lower rates of parasitism than in the Old World. Also, if co-evolutionary selection on parasitoids promotes their adaptation to local fly stocks, parasitoids should have enhanced fitness when reared on local flies rather than allopatric ones. Methods: We collected flies and parasitoids from Igé (France) and from near Seattle (USA). In factorial laboratory experiments, we exposed D. subobscura larvae from both sites to parasitoids (Leptopilina heterotoma) from both sites and then scored parasitoid success rate, impact rate, and fecundity. Results: Despite the generally held belief, the parasitoid community in Seattle is the same as that in Igé and not depauperate. Success rate (probability that an infested fly gave rise to an adult wasp) was high (0.83-0.86) and independent of treatment, showing that invasive and native flies were equally vulnerable to both populations of parasitoids. Seattle flies were larger than Igé flies, and parasitoids emerging from Seattle flies were larger than those emerging from Igé flies. Fecundity of parasitoids reared on Seattle flies was greater than those reared on Igé flies, especially when parasitoids were also from Seattle. Overall, the success of D. subobscura in the New World appears to be unrelated to biogeographical escape from parasitoids because these flies have very high mortality in the presence of local L. heterotoma, at least in the laboratory. Yet L. heterotoma does seem to be locally adapted, having higher fecundity when reared on local flies.

Published
2010

48. Occurrence of arrhenotoky and thelytoky in a parasitic wasp venturia canescens (Hymenoptera: Ichneumonidae): Effect of endosymbionts or existence of two distinct reproductive modes?

Author

Foray, Vincent, Henri, Hélène, Martinez, Sonia, Gibert, Patricia, Desouhant, Emmanuel, Foray, Vincent, Henri, Hélène, Martinez, Sonia, Gibert, Patricia, and Desouhant, Emmanuel

Abstract

Endosymbiotic organisms are known to manipulate the reproductive biology of their hosts. Incomplete prevalence of endosymbiont inducing thelytokous parthenogenesis results in the coexistence of sexual and asexual individuals, and could account for the maintenance of sexual reproduction in certain populations or species. In the parasitoid Venturia canescens, arrhenotokous ("sexual") and thelytokous ("asexual") individuals occur sympatrically. We aimed to determine whether endosymbionts are implicated in the thelytoky of V. canescens. After screening females of the two reproductive modes for several reproductive parasites: bacteria (Wolbachia, Rickettsia, Bacteroidetes, Spiroplasma, Arsenophonus) and Microsporidia, we concluded that thelytoky in V. canescens is not induced by any of these parasites and confirmed its suitability as a biological model for solving the evolutionary enigma of the maintenance of sexual reproduction.

Published
2013

49. Evidence of diversity and recombination in Arsenophonus symbionts of the Bemisia tabaci species complex

Author

Mouton, Laurence, Thierry, Magalie, Henri, Hélène, Baudin, Rémy, Gnankine, Olivier, Reynaud, Bernard, Zchori Fein, Einat, Becker, Nathalie, Fleury, Frédéric, Delatte, Hélène, Mouton, Laurence, Thierry, Magalie, Henri, Hélène, Baudin, Rémy, Gnankine, Olivier, Reynaud, Bernard, Zchori Fein, Einat, Becker, Nathalie, Fleury, Frédéric, and Delatte, Hélène

Abstract

Background Maternally inherited bacterial symbionts infecting arthropods have major implications on host ecology and evolution. Among them, the genus Arsenophonus is particularly characterized by a large host spectrum and a wide range of symbiotic relationships (from mutualism to parasitism), making it a good model to study the evolution of host-symbiont associations. However, few data are available on the diversity and distribution of Arsenophonus within host lineages. Here, we propose a survey on Arsenophonus diversity in whitefly species (Hemiptera), in particular the Bemisia tabaci species complex. This polyphagous insect pest is composed of genetic groups that differ in many ecological aspects. They harbor specific bacterial communities, among them several lineages of Arsenophonus, enabling a study of the evolutionary history of these bacteria at a fine host taxonomic level, in association to host geographical range and ecology. Results Among 152 individuals, our analysis identified 19 allelic profiles and 6 phylogenetic groups, demonstrating this bacterium's high diversity. These groups, based on Arsenophonus phylogeny, correlated with B. tabaci genetic groups with two exceptions reflecting horizontal transfers. None of three genes analyzed provided evidence of intragenic recombination, but intergenic recombination events were detected. A mutation inducing a STOP codon on one gene in a strain infecting one B. tabaci genetic group was also found. Phylogenetic analyses of the three concatenated loci revealed the existence of two clades of Arsenophonus. One, composed of strains found in other Hemiptera, could be the ancestral clade in whiteflies. The other, which regroups strains found in Hymenoptera and Diptera, may have been acquired more recently by whiteflies through lateral transfers. Conclusions This analysis of the genus Arsenophonus revealed a diversity within the B. tabaci species complex which resembles that reported on the larger scale of insect taxono

Published
2012

50. Evidence of diversity and recombination in Arsenophonus symbionts of the Bemisia tabaci species complex

Author

Mouton, Laurence, Thierry, Magalie, Henri, Hélène, Baudin, Rémy, Gnankine, Olivier, Reynaud, Bernard, Zchori Fein, Einat, Becker, Nathalie, Fleury, Frédéric, Delatte, Hélène, Mouton, Laurence, Thierry, Magalie, Henri, Hélène, Baudin, Rémy, Gnankine, Olivier, Reynaud, Bernard, Zchori Fein, Einat, Becker, Nathalie, Fleury, Frédéric, and Delatte, Hélène

Published
2011

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