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Registros recuperados: 42 | |
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Guevelou, Eric; Huvet, Arnaud; Sussarellu, Rossana; Milan, Massimo; Guo, Xinmei; Li, Li; Zhang, Guofan; Quillien, Virgile; Daniel, Jean-yves; Quere, Claudie; Boudry, Pierre; Corporeau, Charlotte. |
AMP-activated protein kinase α (AMPKα) is a key regulator of energy balance in many model species during hypoxia. In a marine bivalve, the Pacific oyster Crassostrea gigas, we analyzed the protein content of adductor muscle in response to hypoxia during 6 h. In both smooth and striated muscles, the amount of full-length AMP-activated protein kinase α (AMPKα) remained unchanged during hypoxia. However, hypoxia induced a rapid and muscle-specific response concerning truncated isoforms of AMPKα. In the smooth muscle, a truncated isoform of AMPKα was increased from 1 to 6 h of hypoxia, and was linked with accumulation of AKT kinase, a key enzyme of the insulin signaling pathway which controls intracellular glucose metabolism. In this muscle, aerobic metabolism... |
Tipo: Text |
Palavras-chave: Marine bivalve; Crassostrea gigas; Hypoxia; AMP-activated protein kinase; Alternative splicing; Adductor muscle. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00119/22998/21397.pdf |
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Huvet, Arnaud; Jeffroy, Fanny; Daniel, Jean-yves; Quere, Claudie; Le Souchu, Pierrick; Van Wormhoudt, A.; Boudry, Pierre; Moal, Jeanne; Samain, Jean-francois. |
In the oyster Crassostrea gigas consumption-related traits, amylase properties and growth were found to be linked through genotypes that differed for polymorphism in the two amylase genes AMYA and AMYB. Modulation of AMYA mRNA level had already been observed in response to food availability, whereas the functional role of AMYB was still unknown. To improve knowledge about the regulation of amylase expression in C. gigas and the respective roles of the two genes, we made an assay of amylase expression at mRNA and enzymatic levels in the digestive gland of oysters that had received dietary supplements of starch. After 18 days, a significant increase of translatable mRNA for AMYB was observed, with a correlated increase in Michaelis-Menten constant Km values... |
Tipo: Text |
Palavras-chave: Alpha-amylase; Crassostrea gigas; Digestive enzyme; Michaelis-Menten constant; Regulation. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00087/19869/17521.pdf |
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Boulais, Myrina; Soudant, Philippe; Le Goic, Nelly; Quere, Claudie; Boudry, Pierre; Suquet, Marc. |
In the Pacific oyster, spermatozoa are characterized by a remarkably long movement phase (i.e., over 24 h) sustained by a capacity to maintain intracellular ATP level. To gain information on oxidative phosphorylation (OXPHOS) functionality during the motility phase of Pacific oyster spermatozoa, we studied 1) changes in spermatozoal mitochondrial activity, that is, mitochondrial membrane potential (MMP), and intracellular ATP content in relation to motion parameters and 2) the involvement of OXPHOS for spermatozoal movement using carbonyl cyanide m-chlorophenyl hydrazone (CCCP). The percentage of motile spermatozoa decreased over a 24 h movement period. MMP increased steadily during the first 9 h of the movement phase and was subsequently maintained at a... |
Tipo: Text |
Palavras-chave: Crassostrea gigas; Intracellular ATP content; Mitochondrial membrane potential; Oxidative phosphorylation; Sperm motility. |
Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00303/41376/40666.pdf |
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Seguineau, Catherine; Soudant, P; Moal, Jeanne; Delaporte, Maryse; Miner, Philippe; Quere, Claudie; Samain, Jean-francois. |
The present study tested two techniques for dietary supplementation of Crassostrea gigas spat with PUFA, such as arachidonic acid (AA). The first technique consisted of a preliminary enrichment and growth of an algal concentrate (T-ISO, Isochrysis sp.) with AA dissolved in an ethanol solution, the whole culture then being fed to the spat. This enrichment increased the AA weight percentage in T-ISO neutral and polar lipids from 0.6 to 22.4% and from 0.4 to 6.8%, respectively. The second delivery technique was direct addition separately of free AA dissolved in ethanol solution and algal concentrate (T-ISO + AA) to the spat-rearing tank. To test the efficiency of these delivery techniques, oyster spat were supplemented with AA-enriched T-ISO, T-ISO + AA, and... |
Tipo: Text |
Palavras-chave: Food supply; Arachidonic acid; Spat; Crassostrea gigas; Dietary. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-1094.pdf |
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Corporeau, Charlotte; Tamayo, David; Pernet, Fabrice; Quere, Claudie; Madec, Stephanie. |
Pacific oyster Crassostrea gigas were inoculated with OsHV-1 at low load (control) or high load (challenged) to better understand the pathogenesis of ostreid herpesvirus 1 (OsHV-1 μVar) and to determine which metabolic pathways might be affected during infection. Animals were sampled for proteomic analysis two days post-injection, at the same time as OsHV-1 initiated an intense replication phase in challenged oysters. Twenty-five abundant protein spots that showed a marked change in accumulated levels were identified using a two-dimensional electrophoresis (2-DE) proteomic approach. Overall, these proteins are involved in cytoskeleton organization, protein turnover, induction of stress signals, signalling pathways and energy metabolism. Challenged oysters... |
Tipo: Text |
Palavras-chave: Marine bivalves; Crassostrea gigas; Herpesvirus; Metabolism; Warburg. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00199/31035/29439.pdf |
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Dudognon, Tony; Guderley, Helga; Quere, Claudie; Soudant, Philippe; Racotta, Ilie; Kraffe, Edouard. |
Although laboratory experiments allow greater control of environmental conditions than field studies, they have several drawbacks. To analyze physiological responses to forcing environmental variables, experimental conditions should mimic natural conditions as closely as possible. For filter-feeding organisms in particular, diet quality and quantity is one of the environmental parameters that can differ markedly between experimental and field conditions. In the hatchery, Pacific oysters, Crassostrea gigas, commonly show good physiological performance and growth on a mixed algal diet of Tisochrysis lutea, formerly Isochrysis aff. galbana clone Tahiti (T-Iso), and Chaetoceros calcitrans, presumably as it provides a good supply of essential polyunsaturated... |
Tipo: Text |
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Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00266/37756/36065.pdf |
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Pernet, Fabrice; Lagarde, Franck; Cesmat, Ludovic; Jeannée, Nicolas; Barret, Jean; Le Gall, Patrik; Quere, Claudie; Fiandrino, Annie; Miguet, Marine; Boulet, Hélène; Keck, Nicolas; Roque D'Orbcastel, Emmanuelle. |
Cette étude avait pour objectif principal de déterminer les facteurs explicatifs de la dynamique spatio-temporelle des surmortalités d’huîtres creuses dans la lagune de Thau. Les facteurs étudiés étaient : la pathologie (détection d’ADN appartenant à l’Ostreid herpesvirus 1 OsHV-1 et au groupe bactérien Vibrio splendidus), l’état énergétique des huîtres (triglycérides, sucres totaux et acides gras comme marqueurs trophiques), les pratiques d’élevage et l’hydrodynamique. Afin de répondre à ces objectifs, nous avons suivi la mortalité d’un lot d’huîtres sentinelles, âgé de moins d’un an, maintenu indemne de mortalité, dans lequel on ne détectait pas d’ADN appartenant à OsHV-1. Le lot a été déployé mi-mars 2011 sur 106 stations dans la lagune de Thau, où les... |
Tipo: Text |
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Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00092/20355/18015.pdf |
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Haberkorn, Hansy; Lambert, Christophe; Le Goic, Nelly; Quere, Claudie; Bruneau, A; Riso, Ricardo; Auffret, Michel; Soudant, Philippe. |
Effects of simultaneous exposure of Pacific oyster, Crassostrea gigas, to both a harmful dinoflagellate that produces Paralytic Shellfish Toxins (PST), Alexandrium minutum, and cadmium (Cd) and copper (Cu), were assessed. Oysters were exposed to a mix of Cd-Cu with two different diets (i.e. A. minutum or Tisochrysis lutea) and compared to control oysters fed A. minutum or T. lutea, respectively, without metal addition. Metals and PST accumulations, digestive gland lipid composition, and cellular and biochemical hemolymph variables were measured after 4 days of exposure. Oysters exposed to Cd-Cu accumulated about thirty-six times less PSTs than oysters exposed to A. minutum alone. Exposure to Cd-Cu induced significant changes in neutral lipids (increase in... |
Tipo: Text |
Palavras-chave: Harmful algae; Metals; Oysters; Toxin accumulation; Physiological effects. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00169/28071/26286.pdf |
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Suquet, Marc; Quere, Claudie; Mingant, Christian; Lebrun, Luc; Ratiskol, Dominique; Miner, Philippe; Cosson, Jacky. |
Sperm characteristics of scallops have not been well described in the scientific literature. The effects of sperm release technique (thermal shock versus serotonin injection), of sperm collection technique (testis sampling versus serotonin injection), of sperm sampling location along the genital tract, of in vitro sperm maturation, and of time post activation on scallop sperm characteristics were assessed in the present work. Whatever sperm release technique used, no significant differences were observed regarding the percentage of motile spermatozoa and the velocity of the average path (YAP). Compared to testicular sperm, a higher percentage of motile spermatozoa, YAP and intracellular adenosine triphosphate (ATP) content were observed for sperm shed... |
Tipo: Text |
Palavras-chave: Spermatozoa; CASA; Maturation; Sperm motility; Bivalve; Pecten maximus. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00157/26852/24983.pdf |
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Epelboin, Yanouk; Quere, Claudie; Pernet, Fabrice; Pichereau, Vianney; Corporeau, Charlotte. |
Here, we assess the physiological effects induced by environmental concentrations of pesticides in Pacific oyster Crassostrea gigas. Oysters were exposed for 14 d to trace levels of metconazole (0.2 and 2 mu g/L), isoproturon (0.1 and 1 mu g/L), or both in a mixture (0.2 and 0.1 mu g/L, respectively). Exposure to trace levels of pesticides had no effect on the filtration rate, growth, and energy reserves of oysters. However, oysters exposed to metconazole and isoproturon showed an overactivation of the sensing-kinase AMP-activated protein kinase alpha (AMPK alpha), a key enzyme involved in energy metabolism and more particularly glycolysis. In the meantime, these exposed oysters showed a decrease in hexokinase and pyruvate kinase activities, whereas 2-DE... |
Tipo: Text |
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Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00284/39490/44227.pdf |
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Da Costa, Fiz; Le Grand, Fabienne; Quere, Claudie; Bougaran, Gael; Cadoret, Jean-paul; Robert, Rene; Soudant, Philippe. |
Standard and mutant Tisochrysis lutea strains were grown in batch culture for 10 days under nitrogen (N)-replete and N-reduced conditions to determine the effects of N supply in culture medium and growth phase on microalgal physiology and biochemistry. These two T. lutea strains were compared in terms of growth, morphology, associated free-living bacterial community, viability, intracellular lipid content (as measured by Bodipy staining), chlorophyll autofluorescence, and biochemical composition, with a focus on lipid class and fatty acid compositions. The standard strain (T) reached higher cell counts regardless of N supply in culture medium. In both T. lutea strains, microalgal final cell density was significantly lower in N-reduced medium. Carbohydrates... |
Tipo: Text |
Palavras-chave: Tisochrysis lutea; Nitrogen limitation; Growth phase; Flow cytometry; Fatty acids; Lipid classes. |
Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00399/51074/51936.pdf |
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Guevelou, Eric; Huvet, Arnaud; Galindo-sanchez, Clara E.; Milan, Massimo; Quillien, Virgile; Daniel, Jean-yves; Quere, Claudie; Boudry, Pierre; Corporeau, Charlotte. |
The hermaphrodite Pacific oyster Crassostrea gigas displays a high energy allocation to reproduction. We studied the expression of AMP-activated protein kinase (AMPK) during gametogenesis in the gonad and characterized the mRNA sequences of the AMPK subunits: the AMPK alpha mRNA sequence was previously characterized; we identified AMPK beta, AMPK gamma, and mRNAs of putative AMPK-related targets following bioinformatics mining on existing genomic resources. We analyzed the mRNA expression of the AMPK alpha, beta, and gamma subunits in the gonads of male and female oysters through a reproductive cycle, and we quantified the mRNA expression of genes belonging to fatty acid and glucose metabolism. AMPK alpha mRNA levels were more abundant in males at the... |
Tipo: Text |
Palavras-chave: AMP-activated protein kinase; Crassostrea gigas; Gametogenesis; Marine bivalve; Reproduction. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00168/27911/26470.pdf |
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Bechemin, Christian; Soletchnik, Patrick; Polsenaere, Pierre; Le Moine, Olivier; Pernet, Fabrice; Protat, Martin; Fuhrmann, Marine; Quere, Claudie; Goulitquer, Sophie; Corporeau, Charlotte; Lapegue, Sylvie; Travers, Marie-agnes; Morga, Benjamin; Garrigues, Manon; Garcia, Celine; Haffner, Philippe; Dubreuil, Christine; Faury, Nicole; Baillon, Laury; Baud, Jean-pierre; Renault, Tristan. |
Mass mortality outbreaks (90-100%) in both juvenile and adult blue mussels were reported in 2014 along the Pertuis Charentais area of the French Atlantic coast. A series of studies were carried out to learn more about the phenomenon through detecting pathogens, describing environmental conditions and establishing the physiological status of the animals. Bacteria identif ied as belonging to the V. splendidus species were detected in dying mussels and seem able to cause mortality in blue mussels in the laboratory. Unusual environmental conditions (large amounts of fresh water, re-suspension of sediments during a series of storms, and a high renewal rate of specific water masses in Brittany’s Pertuis area) may be partially responsible for sparking the phenomen |
Tipo: Text |
Palavras-chave: Mortalités; Moules; Pertuis Charentais; Vibrio splendidus; Environnement; Mortality; Mussels; Pertuis Charentais; Vibrio splendidus; Environment. |
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00312/42343/41682.pdf |
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Da Costa Gonzalez, Fiz; Robert, Rene; Quere, Claudie; Wikfors, Gary H.; Soudant, Philippe. |
Essential fatty acids (EFA) are important for bivalve larval survival and growth. The purpose of this study was to quantitatively assess for the first time through a mass-balance approach dietary EFA incorporation and synthesis within Crassostrea gigas larvae. A first experiment was carried out using two microalgae, Tisochrysis lutea (T) and Chaetoceros neogracile (Cg), as mono- and bi-specific diets. A second experiment using a similar design was performed to confirm and extend the results obtained in the first. Flow-through larval rearing was used for accurate control of food supply and measurement of ingestion. Non-methylene-interrupted fatty acids were synthetized from precursors supplied in the diet: 16:1n-7 and 18:1n-9, mediated by Delta 5... |
Tipo: Text |
Palavras-chave: Fatty acid; Larvae; Lipids; Metabolism; Oyster; Synthesis. |
Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00268/37962/36086.pdf |
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Bechemin, Christian; Soletchnik, Patrick; Polsenaere, Pierre; Le Moine, Olivier; Pernet, Fabrice; Protat, Martin; Fuhrmann, Marine; Quere, Claudie; Goulitquer, Sophie; Corporeau, Charlotte; Renault, Tristan; Lapegue, Sylvie; Travers, Marie-agnes; Morga, Benjamin; Garriques, Manon; Garcia, Celine; Haffner, Philippe; Dubreuil, Christine; Faury, Nicole; Baillon, Laury; Baud, Jean-pierre. |
Suite aux surmortalités observées au sein des élevages de moules touchant à la fois les animaux adultes et les juvéniles au mois de mars, dans les Pertuis Charentais, la Direction Générale de l’Alimentation (DGAl) a adressé une saisine à Ifremer le 04 avril 2014. Celle-ci fait état d’une demande d’appui scientifique et technique d’Ifremer pour tenter d’apporter des éléments de réponse par rapport à cette mortalité subite et importante. L’Ifremer a proposé un projet d’action permettant l’expertise du phénomène de surmortalité de la moule bleue, selon 3 axes : l’impact environnemental, la pathologie et les caractéristiques physiologiques des moules. Il s’agit de mettre en évidence la présence ou non d’agents infectieux connus ou émergents, d’apporter des... |
Tipo: Text |
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Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00229/34022/32387.pdf |
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Pernet, Fabrice; Barret, Jean; Le Gall, Patrik; Malet, Nathalie; Pastoureaud, Annie; Munaron, Dominique; De Lorgeril, Julien; Bachere, Evelyne; Vaquer, Andre; Huvet, Arnaud; Corporeau, Charlotte; Normand, Julien; Boudry, Pierre; Moal, Jeanne; Quere, Claudie; Quilien, Virgile; Daniel, Jean-yves; Pepin, Jean-francois; Saulnier, Denis; Gonzalez, Jean-louis. |
This study was conducted in the Mediterranean area during a mass mortality event of Pacific oyster Crassostrea gigas. The objectives of this work were to increase our understanding of the mass mortality phenomena in Pacific oysters, to identify risky cultivation practises and to propose mitigation strategies. In the first part of this work, we followed environmental parameters of the Thau lagoon in relation with mortality events. Then, we compared mortality and growth parameters of oysters as a function of their origins, their development stages and cultivation sites in relation with energetic, reproduction and pathogens. Finally, we conducted transfer experiments where oysters maintained free of mortality in open sea were transferred in the Thau lagoon... |
Tipo: Text |
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Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00002/11354/7927.pdf |
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Dudognon, Tony; Soudant, Philippe; Seguineau, Catherine; Quere, Claudie; Auffret, Michel; Kraffe, Edouard. |
Sessile animals that live on the foreshore undergo tidal cycles, and have to face variations in physical and chemical parameters such as oxygen concentration. During emersion, availability of dissolved oxygen can be lowered for bivalves, which have only a small reserve of seawater inside their closed shell. Differences in oxygen concentration are thus expected to lead to modifications of the metabolism, including changes in mitochondrial activity. Previous studies investigated air exposure under extreme conditions, which do not always reflect environmental conditions these invertebrates have to cope with. In this study, oxidative capacities of gill mitochondria of the oyster Crassostrea gigas were studied during a tidal cycle period, by comparing oysters... |
Tipo: Text |
Palavras-chave: Mitochondria; Oxygen consumption; ATP production; Respiratory chain inhibitor; Crassostrea gigas. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00157/26854/24981.pdf |
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Pernet, Fabrice; Lagarde, Franck; Jeannee, Nicolas; Daigle, Gaetan; Barret, Jean; Le Gall, Patrik; Quere, Claudie; Roque D'Orbcastel, Emmanuelle. |
Although spatial studies of diseases on land have a long history, far fewer have been made on aquatic diseases. Here, we present the first large-scale, high-resolution spatial and temporal representation of a mass mortality phenomenon cause by the Ostreid herpesvirus (OsHV-1) that has affected oysters (Crassostrea gigas) every year since 2008, in relation to their energetic reserves and the quality of their food. Disease mortality was investigated in healthy oysters deployed at 106 locations in the Thau Mediterranean lagoon before the start of the epizootic in spring 2011. We found that disease mortality of oysters showed strong spatial dependence clearly reflecting the epizootic process of local transmission. Disease initiated inside oyster farms spread... |
Tipo: Text |
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Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00181/29249/27663.pdf |
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Registros recuperados: 42 | |
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