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Registros recuperados: 57 | |
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Gueguen, Yannick; Montagnani, Caroline; Joubert, Caroline; Marie, Benjamin; Belliard, Corinne; Tayale, Alexandre; Fievet, Julie; Levy, Peva; Piquemal, David; Marin, Frederic; Le Moullac, Gilles; Ky, Chin-long; Garen, Pierre; Lo, Cedrick; Saulnier, Denis. |
Tahiti’s pearl farming industry plays a major socio-economic role in French Polynesia. In an increasingly competitive market where the production of high quality pearls becomes essential, research can help secure and ensure sustainable production. In that context, Ifremer, in close collaboration with the “direction des resources marines” (French Polynesian government agency) has developed research projects on the “sustainable development of pearl farming”. This program is organized along 3 axes: (1) understanding the animal physiology and initiating a genetically selective breeding program of donor oysters; (2) understanding pearl oyster larvae dispersal and recruitment; (3) understanding the molecular mechanisms underlying biomineralization processes... |
Tipo: Text |
Palavras-chave: Pearl oyster; Biomineralization; Pinctada margaritifera. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00167/27840/26049.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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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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Cardona, Emilie; Saulnier, Denis; Lorgeoux, Benedicte; Chim, Liet; Gueguen, Yannick. |
This study compares the antioxidant and antimicrobial transcriptional expression of blue shrimps reared according to two different systems, BioFloc Technology (BFT) and Clear sea Water (CW) and their differential responses when facing an experimental sublethal hydrogen peroxide stress. After 30 days of rearing, juvenile shrimps were exposed to H2O2 stress at a concentration of 30 ppm during 6 hours. The oxidative stress caused by H2O2 was examined in the digestive glands of the shrimp, in which antioxidant enzyme (AOE) and antimicrobial peptide (AMP) gene expression were analysed by quantitative real-time PCR. Results showed that rearing conditions did not affect the expression of genes encoding AOEs or AMPs. However, H2O2 stress induced a differential... |
Tipo: Text |
Palavras-chave: Biofloc; Shrimps; Antimicrobial peptides; Antioxidant enzymes. |
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00270/38116/36269.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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Gueguen, Yannick; Czorlich, Yann; Mastail, Max; Le Tohic, Bruno; Defay, Didier; Lyonnard, Pierre; Marigliano, Damien; Gauthier, Jean-pierre; Bari, Hubert; Lo, Cedrik; Chabrier, Sebastien; Le Moullac, Gilles. |
Cultured pearls are human creations formed by inserting a nucleus and a small piece of mantle tissue into a living shelled mollusc, usually a pearl oyster. Although many pearl observations intuitively suggest a possible rotation of the nucleated pearl inside the oyster, no experimental demonstration of such a movement has ever been done. This can be explained by the difficulty of observation of such a phenomenon in the tissues of a living animal. To investigate this question of pearl rotation, a magnetometer system was specifically engineered to register magnetic field variations with magnetic sensors from movements of a magnetic nucleus inserted in the pearl oyster. We demonstrated that a continuous movement of the nucleus inside the oyster starts after a... |
Tipo: Text |
Palavras-chave: Pearl oyster; Pearl rotation; Biomineralization. |
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00275/38598/37127.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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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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Linard, Clementine; Gueguen, Yannick; Moriceau, Jacques; Soyez, Claude; Hui, Belinda; Raoux, Aurore; Cuif, Jean Pierre; Cochard, Jean-claude; Le Pennec, Marcel; Le Moullac, Gilles. |
Marine mollusc shell growth has been widely measured using fluorochrome marking. In order to test the efficiency and reliability of calcein staining on P. margaritifera shells and pearls, the present study examined two administration methods, different concentrations and several immersion times.Immersion in a 150 mg.L-1 calcein solution for 12 h to 24 h appeared to be the best method for marking P. margaritifera shells. For pearl marking, injection of a 200 mg.L-1 calcein solution into the pearl pouch was the optimal method. Calcein marking was then used to measure the influence of food resource levels on the shell growth. Groups of 23-month-old P. margaritifera were fed at three trophic levels for two months. The two highest food levels tested (6 000... |
Tipo: Text |
Palavras-chave: Bivalvia; Pearl; Shell; Growth; Scanning electron microscope. |
Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00028/13907/11195.pdf |
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Cardona, Emilie; Gueguen, Yannick; Magré, Kevin; Lorgeoux, Bénédicte; Piquemal, David; Pierrat, Fabien; Noguier, Florian; Saulnier, Denis. |
Background Biofloc technology (BFT), a rearing method with little or no water exchange, is gaining popularity in aquaculture. In the water column, such systems develop conglomerates of microbes, algae and protozoa, together with detritus and dead organic particles. The intensive microbial community presents in these systems can be used as a pond water quality treatment system, and the microbial protein can serve as a feed additive. The current problem with BFT is the difficulty of controlling its bacterial community composition for both optimal water quality and optimal shrimp health. The main objective of the present study was to investigate microbial diversity of samples obtained from different culture environments (Biofloc technology and clear... |
Tipo: Text |
Palavras-chave: Shrimp; Biofloc; Clear sea water; Bacterial communities; Culture environment; Microbiota. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00346/45694/45314.pdf |
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De Lorgeril, Julien; Gueguen, Yannick; Goarant, Cyrille; Goyard, Emmanuel; Mugnier, Chantal; Fievet, Julie; Piquemal, D; Bachere, Evelyne. |
Understanding of antimicrobial defence mechanisms of penaeid shrimp should help in the design of efficient strategies for the management and disease control in aquaculture. In this study, we have specifically analysed the expression in circulating hemocytes of antimicrobial peptides (AMPs) encoding genes, such as PEN2 and PEN3, ALF, crustin, lysozyme and a putative cysteine-rich peptide. We evidenced a relationship between the level of expression of some AMPs and the successful response of the shrimp, Litopenaeus stylirostris, to circumvent a pathogenic Vibrio penaeicida infection. Additionally, significant differences in some AMP transcript amounts are evidenced between control, non-selected shrimp line and the third generation breeding of shrimp selected... |
Tipo: Text |
Palavras-chave: Real time PCR; Cysteine rich peptide; Crustin; Anti LPS factor; Lysozyme; Penaeidins; Immune response; Vibrio penaeicida; Penaeid; Decapoda; Crustacean. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4524.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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Marie, Benjamin; Joubert, Caroline; Belliard, Corinne; Tayale, Alexandre; Zanella-cleon, Isabelle; Marin, Frederic; Gueguen, Yannick; Montagnani, Caroline. |
Nacre of the Pinctada pearl oyster shells is composed of 98% CaCO3 and 2% organic matrix. The relationship between the organic matrix and the mechanism of nacre formation currently constitutes the main focus regarding the biomineralization process. In this study, we isolated a new nacre matrix protein in P. margaritifera and P. maxima, we called Pmarg- and Pmax-MRNP34 (methionine-rich nacre protein). MRNP34 is a secreted hydrophobic protein, which is remarkably rich in methionine, and which is specifically localised in mineralizing the epithelium cells of the mantle and in the nacre matrix. The structure of this protein is drastically different from those of the other nacre proteins already described. This unusual methionine-rich protein is a new member in... |
Tipo: Text |
Palavras-chave: Matrix protein; Methionine-rich; Biomineralization; Mollusc; Nacre; Calcifying mantle. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00077/18870/16645.pdf |
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Gueguen, Yannick; Herpin, Amaury; Aumelas, André; Garnier, Julien; Fievet, Julie; Escoubas, Jean-michel; Bulet, Philippe; Gonzalez, Marcelo; Lelong, Christophe; Favrel, Pascal; Bachere, Evelyne. |
In invertebrates, defensins were found in arthropods and in the mussels. Here, we report for the first time the identification and characterization of a defensin (Cg-Def) from an oyster. Cg-def mRNA was isolated from Crassostrea gigas mantle using an expressed sequence tag approach. To gain insight into potential roles of Cg-Def in oyster immunity, we produced the recombinant peptide in Escherichia coli, characterized its antimicrobial activities, determined its solution structure by NMR spectroscopy, and quantified its gene expression in vivo following bacterial challenge of oysters. Recombinant Cg-Def was active in vitro against Gram-positive bacteria but showed no or limited activities against Gram-negative bacteria and fungi. The activity of Cg-Def was... |
Tipo: Text |
Palavras-chave: Crassostrea gigas; Genomic library; Microbiology; Defensin; Oyster. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-2127.pdf |
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Registros recuperados: 57 | |
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