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Registros recuperados: 57 | |
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Teaniniuraitemoana, Vaihiti; Lepretre, Maxime; Levy, Peva; Vanaa, Vincent; Parrad, Sophie; Gaertner-mazouni, Nabila; Gueguen, Yannick; Huvet, Arnaud; Le Moullac, Gilles. |
The black-lip pearl oyster Pinctada margaritifera is a protandrous hermaphrodite species. Its economic value has led to the development of controlled hatchery reproduction techniques, although many aspects remain to be optimized. In order to understand reproductive mechanisms and their controlling factors, two independent experiments were designed to test hypotheses of gametogenesis and sex ratio control by environmental and hormonal factors. In one, pearl oysters were exposed under controlled conditions at different combinations of temperature (24 and 28°C) and food level (10,000 and 40,000 cells mL−1); whereas in the other, pearl oysters were conditioned under natural conditions into the lagoon and subjected to successive 17β-estradiol injections (100 μg... |
Tipo: Text |
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Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00285/39638/38184.pdf |
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Gonzalez, Marcelo; Gueguen, Yannick; Destoumieux Garzon, Delphine; Romestand, Bernard; Fievet, Julie; Pugniere, M; Roquet, F; Escoubas, Jean-michel; Vandenbulcke, F; Levy, O; Saune, Laure; Bulet, P; Bachere, Evelyne. |
A cDNA sequence with homologies to members of the LPS-binding protein and bactericidal/permeability-increasing protein (BPI) family was identified in the oyster Crassostrea gigas. The recombinant protein was found to bind LIPS, to display bactericidal activity against Escherichia coli, and to increase the permeability of the bacterial cytoplasmic membrane. This indicated that it is a BPI rather than an LPS-binding protein. By in situ hybridization, the expression of the C gigas BPI (Cg-bpi) was found to be induced in hemocytes after oyster bacterial challenge and to be constitutive in various epithelia of unchallenged oysters. Thus, Cg-bpi transcripts were detected in the epithelial cells of tissues/organs in contact with the external environment (mantle,... |
Tipo: Text |
Palavras-chave: Oyster innate immunity; Mollusk; Hemocyte; Epithelia; Antimicrobial. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-3564.pdf |
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Tayale, Alexandre; Gueguen, Yannick; Treguier, Cathy; Le Grand, Jacqueline; Cochennec-laureau, Nathalie; Montagnani, Caroline; Ky, Chin-long. |
Producing high quality cultured black pearls from Pinctada margaritifera is one of the major challenges for the "pearl oyster" industry in French Polynesia. In order to assess donor effect on cultured pearl quality, wild Pinctada margaritifera originating from the Tuamotu Archipelago were used in a duplicated grafting experiment. After 12 months of culture, nucleus retention was assessed and seven pearl quality traits recorded on the 454 cultured pearls harvested from the experiment. The traits scored were nacre thickness and pearl weight, surface defects, lustre, grade, and the colour components: 1) darkness of cultured pearl colour, and 2) visual perception of colour class (bodycolor and/or overtone). Our results demonstrate for the first time that... |
Tipo: Text |
Palavras-chave: Cultured pearl oyster; Pearl quality; Nacre; Donor mollusc; Genetic selection; Pteriidae; Blacklip pearl oyster; Pinctada margaritifera; French Polynesia. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00116/22757/20541.pdf |
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Rosa, Rafael Diego; Vergnes, Agnes; De Lorgeril, Julien; Goncalves, Priscila; Perazzolo, Luciane Maria; Saune, Laure; Romestand, Bernard; Fievet, Julie; Gueguen, Yannick; Bachere, Evelyne; Destoumieux-garzon, Delphine. |
Antilipopolysaccharide factors (ALFs) have been described as highly cationic polypeptides with a broad spectrum of potent antimicrobial activities. In addition, ALFs have been shown to recognize LPS, a major component of the Gram-negative bacteria cell wall, through conserved amino acid residues exposed in the four-stranded beta-sheet of their three dimensional structure. In penaeid shrimp, ALFs form a diverse family of antimicrobial peptides composed by three main variants, classified as ALF Groups A to C. Here, we identified a novel group of ALFs in shrimp (Group D ALFs), which corresponds to anionic polypeptides in which many residues of the LPS binding site are lacking. Both Group B (cationic) and Group D (anionic) shrimp ALFs were produced in a... |
Tipo: Text |
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Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00160/27077/25236.pdf |
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Fleury, Elodie; Huvet, Arnaud; Lelong, Christophe; De Lorgeril, Julien; Boulo, Viviane; Gueguen, Yannick; Bachere, Evelyne; Tanguy, Arnaud; Moraga, Dario; Fabioux, Caroline; Lindeque, Penelope; Shaw, Jenny; Reinhardt, Richard; Prunet, Patrick; Davey, Grace; Lapegue, Sylvie; Sauvage, Christopher; Corporeau, Charlotte; Moal, Jeanne; Gavory, Frederick; Wincker, Patrick; Moreews, Francois; Klopp, Christophe; Mathieu, Michel; Boudry, Pierre; Favrel, Pascal. |
Background: Although bivalves are among the most-studied marine organisms because of their ecological role and economic importance, very little information is available on the genome sequences of oyster species. This report documents three large-scale cDNA sequencing projects for the Pacific oyster Crassostrea gigas initiated to provide a large number of expressed sequence tags that were subsequently compiled in a publicly accessible database. This resource allowed for the identification of a large number of transcripts and provides valuable information for ongoing investigations of tissue-specific and stimulus-dependant gene expression patterns. These data are crucial for constructing comprehensive DNA microarrays, identifying single nucleotide... |
Tipo: Text |
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Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6770.pdf |
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Teaniniuraitemoana, Vaihiti; Huvet, Arnaud; Levy, Peva; Klopp, Christophe; Lhuillier, Emeline; Gaertner-mazouni, Nabila; Gueguen, Yannick; Le Moullac, Gilles. |
Background Black pearl farming is based on culture of the blacklip pearl oyster Pinctada margaritifera (Mollusca, lophotrochozoa), a protandrous hermaphrodite species. At first maturation, all individuals are males. The female sex appears progressively from two years old, which represents a limitation for broodstock conditioning for aquaculture production. In marine mollusks displaying hermaphroditic features, data on sexual determinism and differentiation, including the molecular sex determining cascade, are scarce. To increase genomic resources and identify the molecular mechanisms whereby gene expression may act in the sexual dimorphism of P. margaritifera, we performed gonad transcriptome analysis. Results The gonad transcriptome of P. margaritifera... |
Tipo: Text |
Palavras-chave: Pinctada margaritifera; Gametogenesis; Transcriptome; Differential expression; Sex determinism. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00201/31194/29593.pdf |
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Lemer, Sarah; Saulnier, Denis; Gueguen, Yannick; Planes, Serge. |
Background: Color polymorphism in the nacre of pteriomorphian bivalves is of great interest for the pearl culture industry. The nacreous layer of the Polynesian black-lipped pearl oyster Pinctada margaritifera exhibits a large array of color variation among individuals including reflections of blue, green, yellow and pink in all possible gradients. Although the heritability of nacre color variation patterns has been demonstrated by experimental crossing, little is known about the genes involved in these patterns. In this study, we identify a set of genes differentially expressed among extreme color phenotypes of P. margaritifera using a suppressive and subtractive hybridization (SSH) method comparing black phenotypes with full and half albino individuals.... |
Tipo: Text |
Palavras-chave: Differential expression; Biomineralization; Nacre; Pearl; Pigmentation; Albino. |
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00275/38627/37167.pdf |
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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 |
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Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00461/57234/59228.pdf |
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Le Moullac, Gilles; Soyez, Claude; Vidal-dupiol, Jeremie; Belliard, Corinne; Fievet, Julie; Sham-koua, Manaarii; Lo-yat, Alain; Saulnier, Denis; Gaertner-mazouni, N.; Gueguen, Yannick. |
The possible consequences of acidification on pearl farming are disruption of oyster metabolism and change in growth. In the laboratory, we studied the impact of pCO2 (3540, 1338 and 541μatm) on the physiology of pearl oysters exposed for 100 days. This experiment was repeated after an interval of one year. Several physiological compartments were examined in pearl oysters: the scope for growth by measuring ingestion, assimilation and oxygen consumption, gametogenesis by means of histological observations, shell growth by measurement and observation by optical and electronic microscopy, and at molecular level by measuring the expression of nine genes of mantle cells implied in the biomineralisation process. Results from both experiments showed that high... |
Tipo: Text |
Palavras-chave: Global change; Pearl oyster; Bioenergetic; Biomineralization; Pacific Ocean; French Polynesia. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00321/43189/42737.pdf |
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De Lorgeril, Julien; Escoubas, Jean Michel; Loubiere, Vincent; Pernet, Fabrice; Le Gall, Patrik; Vergnes, Agnes; Aujoulat, Fabien; Jeannot, Jean-luc; Jumas-bilak, Estelle; Got, Patrice; Gueguen, Yannick; Destoumieux-garzon, Delphine; Bachere, Evelyne. |
Since 2008, juvenile Crassostrea gigas oysters have suffered from massive mortalities in European farming areas. This disease of complex etiology is still incompletely understood. Triggered by an elevated seawater temperature, it has been associated to infections by a herpes virus named OsHV-1 as well as pathogenic vibrios of the Splendidus clade. Ruling out the complexity of the disease, most of our current knowledge has been acquired in controlled experiments. Among the many unsolved questions, it is still ignored what role immunity plays in the capacity oysters have to survive an infectious episode. Here we show that juvenile oysters susceptible to the disease mount an inefficient immune response associated with microbial permissiveness and death. We... |
Tipo: Text |
Palavras-chave: Host pathogen interaction; Innate immunity; Invertebrate; Mollusk; In situ mortality; Total bacteria; Crassostrea gigas. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00433/54470/55845.pdf |
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Gueguen, Yannick; Gaertner-mazouni, Nabila; Lo, Cedrik; Le Moullac, Gilles. |
The paper presents a state of the art on knowledge of the black pearl oyster aquaculture at the scale of French Polynesia. It also introduces the main results obtained throughout the multi-partners POLYPERL project. The goal of this project was to develop an integrated and participative action-research of the pearl oyster culture system, focusing on the environmental, technological, economical and societal dimensions impacting the industry. The research proposed ranges from the understanding of biological phenomena of the production system to socio-economic aspects and governance of the industry, taking into account the management of anthropogenic, climate and health risks. We introduce here the different papers from the POLYPERL project that are compiled... |
Tipo: Text |
Palavras-chave: Pearl culture; Global change; French Polynesia; Pinctada margaritifera. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00346/45698/45320.pdf |
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Maamaatuaiahutapu, Moana; Joufoques, Vaiana; Tamata, Thiery; Dupieux, Sylvain; Teissier, Alexandre; Rarahu, David; Remoissenet, Georges; Gasset, Eric; Knockaert, Camille; Gueguen, Yannick; Coves, Denis. |
Ce rapport traite de la poursuite de l’acquisition de connaissances, du début du transfert vers le secteur privé et des futurs travaux sur de l’élevage du Paraha peue (Platax orbicularis). Acquisition de connaissances porte sur (i) Grossissement en cages en fonction du site d’élevage, tests de produits immuno-stimulants, définition de traitements anti-parasitaires, mise au point des méthodes de transport d’alevins et la mise en cages précoces d’animaux de 1 g pour le transport par voie aérienne vers les îles (i.i.) Synchronisation des pontes et mise en place d’un plan de croisement de géniteurs diminuant le risque de consanguinité et permettant un progrès génétique par la domestication et/ou la sélection, ainsi que la mise au point d’outils de... |
Tipo: Text |
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Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/00128/23887/21820.pdf |
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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 |
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David, R.; Treguier, Cathy; Montagnani, Caroline; Belliard, Corinne; Levy, Peva; Nedelec, Georges; Joufoques, Vaiana; Remoissenet, G.; Gueguen, Yannick; Cochennec-laureau, Nathalie. |
Tipo: Text |
Palavras-chave: Betanodavirus; Detection; French Polynesia; Genotype; Platax orbicularis. |
Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00003/11380/7972.pdf |
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Schmitt, Paulina; Gueguen, Yannick; Desmarais, Erick; Bachere, Evelyne; De Lorgeril, Julien. |
Background: To gain insight into the molecular diversity of antimicrobial peptides and proteins in the oyster Crassostrea gigas, we characterized and compared the sequence polymorphism of the antimicrobial peptides (AMPs), Cg-Defensins (Cg-Defs) and Cg-Proline Rich peptide (Cg-Prp), and of the bactericidal permeability increasing protein, Cg-BPI. For that, we analyzed genomic and transcript sequences obtained by specific PCR amplification and in silico searches. Results: High diversification among the three antimicrobial effectors was evidenced by this polymorphism survey. On the basis of sequence phylogenies, each AMP aggregates into clearly defined groups of variants and is the product of a multigenic family displaying a variety of gene structures. In... |
Tipo: Text |
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Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00001/11182/6691.pdf |
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Registros recuperados: 57 | |
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