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Registros recuperados: 23 | |
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Moal, Jeanne; Samain, Jean-francois; Le Coz, Jean-rene; Daniel, Jean-yves. |
Crassostrea gigas oysters cultivated in Marennes-Oleron Bay (France), face seasonal variations in the environment: salinity, turbidity, phytoplanktonic production, and the tidal rhythm of emersion. The oysters are maintained at different depths to reduce competition for space (e.g. by settlement of mussel spat). The physiological responses of two groups of oysters to different periods of emersion were studied using a seasonal sampling strategy: one group was on a flat part of the area, and the effect of emersion was studied in a short time survey (less than three hours emersion at low tide); the other was located in a very narrow place with a steep slope. This group was subdivided into three, according to bathymetric position, to study the long term effect... |
Tipo: Text |
Palavras-chave: Crassostrea gigas; Physiology; Emersion; AEC; Digestive enzimes; Marennes-Oleron Bay. |
Ano: 1989 |
URL: http://archimer.ifremer.fr/doc/00038/14885/12208.pdf |
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Huvet, Arnaud; Degremont, Lionel; Labreuche, Yannick; Daniel, Jean-yves; Dubrunfaut, Thomas; Boudry, Pierre; Haure, Joel; Bedier, Edouard; Ropert, Michel; Herpin, Amaury; Cunningham, Charles; Moal, Jeanne; Samain, Jean-francois. |
Summer mortality associated with juveniles of the oyster Crassostrea gigas is the result of a complex interaction between the host, pathogens and environment. Divergent selection based on summer survival have been applied to produce families with resistant and susceptible progeny. Here, we describe the use of suppression subtractive hybridization to generate 150 clones that were differentially regulated between resistant and susceptible F2 progeny. The nucleotide sequence of these 150 clones was determined. Among the 25 unique sequences that matched with the products of known genes, those putatively implicated in energy generation (12%) and immune function (16%), systems suspected to be implicated in summer mortality, were extended and analyzed by real... |
Tipo: Text |
Palavras-chave: Selection; Gene; Genetic; Summer mortality; Crassostrea gigas; Pacific oysters. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/acte-3447.pdf |
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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; Fleury, Elodie; Corporeau, Charlotte; Quillien, Virgile; Daniel, Jean-yves; Riviere, Guillaume; Boudry, Pierre; Fabioux, Caroline. |
We investigated the role of oyster gonadal TGF beta (og-TGF beta) in the reproduction of Crassostrea gigas, using an in vivo RNA interference approach. We designed double-stranded RNA targeting og-TGF beta, which is specifically expressed in the somatic cells surrounding germ cells in the gonad of both male and female oysters. In vivo injection of this og-TGF beta dsRNA into the gonad led to knock-down phenotypes for both sexes, with significant reduction (77.52% relative to controls) of the gonad area, lowered reproductive effort and germ cell under-proliferation. Interestingly, half of the injected females halted their vitellogenesis, since we were only able to observe pre-vitellogenic oocytes. In addition, apoptotic germ cells and haemocytes infiltrated... |
Tipo: Text |
Palavras-chave: Marine bivalve; Crassostrea gigas; Reproduction; RNA interference; Transforming growth factor-beta. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00087/19794/17486.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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Samain, Jean-francois; Moal, Jeanne; Alayse-danet, Anne-marie; Daniel, Jean-yves; Le Coz, Jean-rene. |
Model for Rapid Detection of Sublethal Effects of Pollutants. II. An in situ Example: Anomalous Metabolism of the Hyponeustonic Copepod Anomalocera patersoni Coinciding with an Oil Spill An unusual correlation has been obsemed between the amylase and trypsin content of a natural zooplankton population and of the hyponeustonic copepod Anomalocera patersoni and the oil spill of the "Amoco Cadiz" in 1978. This anomaly has also been obsewed in Artemia sp. cultures (San Francisco Bay strain) poisoned by copper. This phenomenon could originate from a general physiological perturbation. Such a non-specific perturbation could explain the anormal correlation between parameters which are usually independent and specifically regulated. The determination of such... |
Tipo: Text |
Palavras-chave: Histoire Ifremer. |
Ano: 1981 |
URL: http://archimer.ifremer.fr/doc/1981/publication-5362.pdf |
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Samain, Jean-francois; Moal, Jeanne; Daniel, Jean-yves; Le Coz, Jean-rene. |
The ingestion rate and the resulting assimilation calculated by means of a law taking into account activities of the digestive enzymes (amylase and trypsin) on the carbohydrates and proteins ingested, are determined in two experiments on Artemia. They are fed the same species of phytoplankton (Tetraselmis suecica), at the same concentration but with two chemical compositions. In one experiment, the cells are rich in carbohydrates and poor in proteins, and in the second one they are poor in carbohydrates, rich in proteins. Different observed ingestion rates induce a balance in proteins, and a large difference in the carbohydrates ingested. When digestive enzymes are taken into account, the assimilated carbohydrates and proteins are similar (explaining the... |
Tipo: Text |
Palavras-chave: Histoire Ifremer. |
Ano: 1981 |
URL: http://archimer.ifremer.fr/doc/1981/publication-5360.pdf |
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Fleury, Elodie; Moal, Jeanne; Boulo, Viviane; Daniel, Jean-yves; Mazurais, David; Henaut, Alain; Corporeau, Charlotte; Boudry, Pierre; Favrel, Pascal; Huvet, Arnaud. |
Summer mortality of the Pacific oyster Crassostrea gigas is the result of a complex interaction between oysters, their environment, and pathogens. Heredity appears to be a major factor determining the sensitivity of oysters to summer mortality, allowing resistant (R) and susceptible (S) lines to be produced. We conducted genome-wide expression profiling of R and S gonads during the 3-month period preceding a summer mortality event, using a cDNA microarray that we designed. ANOVA analysis revealed that 34 genes were differentially expressed between R and S lines on four dates preceding the mortality event. Annotation of some of these genes highlights reproduction and its allocation and antioxidant defenses as the main pathways that operate differentially... |
Tipo: Text |
Palavras-chave: Mollusca; Bivalvia; Gene expression; CDNA microarrays; Reproduction; Oxidative stress; Energy metabolism. |
Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00005/11590/8258.pdf |
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Omnes, Marie-helene; Temey, Yann; Daniel, Jean-yves; Nicolas, Jean-louis. |
Bacterial infections have been suspected to be one cause of variable success in the incubation of turbot (Scophthalmus maximus) eggs. The assessment of bacterial flora (bacterial environment) associated with ova, sperm and developing eggs was conducted just at stripping gametes and during incubation. Gametes were collected in sterile conditions before fertilization. Eggs were held in an open-circulation 401 incubator, at 13 degree C during 6 days until hatching. Samples of those were collected every day. They were rinsed several times with sterile seawater, counted and grown. Viable counts of bacteria were determined on two media, Zobell and TCBS agar. Epibiotic bacteria on the surface of the eggs and impact on the chorion were observed at scanning... |
Tipo: Text |
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Ano: 1993 |
URL: http://archimer.ifremer.fr/doc/00199/31015/29425.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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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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Samain, Jean-francois; Cochard, Jean-claude; Chevolot, Lionel; Daniel, Jean-yves; Jeanthon, C.; Le Coz, Jean-rene; Marty, Y.; Moal, Jeanne; Prieur, D.; Salaun, Michele. |
Some positive growth differences can be observed, all year long, in Pecten maximus larvae cultivated in an old fishpond, compared with the water which flows into it periodically. These waters are filtered at 1 µm through CUNO cartridges. Moreover, the larvae are cultivated in the same light, temperature and food (cultured phytoplankton) conditions. This difference is significant in terms of larvae size, dry weight, organic matter, ashes, total proteins, glycogen, and lipids. A series of preliminary observations on the chemical composition of these two waters after filtration (amino acids, fatty acids, organic mater, nutritive salts), on the bacterial flora (total, heterotrophic organisms, vibrio), on the particular material using electron microscopy, on... |
Tipo: Text |
Palavras-chave: Larve; Ecloserie; Pecten maximus; Facteur croissance; Qualité eau. |
Ano: 1986 |
URL: http://archimer.ifremer.fr/doc/1986/acte-6185.PDF |
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Gagnaire, Beatrice; Gay, Melanie; Huvet, Arnaud; Daniel, Jean-yves; Saulnier, Denis; Renault, Tristan. |
To assess the impact of pollution induced by pesticides on Pacific oyster, Crassostrea gigas, health in France, in vivo effects of combined pesticide exposure and bacterial challenge on cell activities and gene expression in hemocytes were tested using flow cytometry and real-time PCR. As a first step, an in vivo model of experimental contamination was developed. Pacific oysters were exposed to a mixture of eight pesticides (atrazine, glyphosate, alachlor, metolachlor, fosetyl-alumimium, terbuthylazine, diuron and carbaryl) at environmentally relevant concentrations over a 7-day period. Hemocyte parameters (cell mortality, enzyme activities and phagocytosis) were monitored using flow cytometry and gene expression was evaluated by real-time PCR (RT-PCR).... |
Tipo: Text |
Palavras-chave: Gene expression; Flow cytometry; Vibrio splendidus; Pathogenesis; Phagocytosis; Hemocyte; Pesticides; Bivalve immunity; Crassostrea gigas; Pacific oyster. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-3022.pdf |
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Robert, Rene; Moal, Jeanne; Campillo, Maria-josé; Daniel, Jean-yves. |
Pecten maximus larvae exhibit amylase as a main digestive enzyme indicating the possibility of starch hydrolysis. The food value of Rhodomonas salina and Porphyridium cruentum, both rich in starch, on the development of Pecten maximus larvae was investigated. The larval development was studied by means of an image analysis technique and epifluorescence microscopy was used for detecting ingestion and digestion of each phytoplankton species. The biochemical contents of algae and larvae were also assessed. The best growth of Pecten maximus larvae was observed when fed with the mixture PTS (plurispecific control). No growth was observed for larvae fed with Porphyridium cruentum of which most of the population died on day 16 (90%). This algal species was... |
Tipo: Text |
Palavras-chave: Larvae; Food value; Pecten maximus. |
Ano: 1994 |
URL: http://archimer.ifremer.fr/doc/1994/publication-6192.PDF |
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Fabioux, Caroline; Huvet, Arnaud; Lelong, C; Robert, Rene; Pouvreau, Stephane; Daniel, Jean-yves; Mingant, Christian; Le Pennec, M. |
The oyster vasa-like gene was previously demonstrated to be specifically expressed in germline cells of adult oysters Crassostrea gigas. In the present study, this gene was used as a molecular marker to establish the developmental pattern of germline cells during oyster ontogenesis. using whole-mount in situ hybridization and real-time PCR. The Oyvlg transcripts appeared to be localized to the vegetal pole of unfertilized oocytes and maternally transmitted to embryos. At early development, these maternal transcripts were observed to segregate into a single blastomere, from the CD macromere of 2-cell stage to the 4d mesentoblast of blastula. From late blastula stage, the mesentoblast divided into two cell clumps that migrated to both sides of the larvae... |
Tipo: Text |
Palavras-chave: Primordial germ cells; Oyster vasa like gene; Germline; Development; Crassostrea gigas. |
Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/2004/publication-648.pdf |
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Le Moullac, Gilles; Cheize, Marie; Gastineau, Olivier; Daniel, Jean-yves; Le Coz, Jean-rene; Huvet, Arnaud; Moal, Jeanne; Pouvreau, Stephane; Van Wormhoudt, A; Samain, Jean-francois. |
The purpose of this study is to examine the response of the oyster Crassostrea gigas to sulphide at different biological scales. A first experiment was designed to measure for 20 h the clearance (CR) and oxygen consumption (OC) rates of oysters exposed at different concentrations of sulphide (0, 3, 6, 12, 20, and 40 mu M). The second experiment was carried out to evaluate the metabolic adaptations to chronic sulphide exposure for 10 days by measuring PK and PEPCK enzyme activities, succinate and alanine content, the adenylate energy charge (AEC), and the activity of the electron transport system (ETS)in whole oysters at above 20 mu M. PK and PEPCK mRNAs and enzyme activities have been measured in adductor muscle. When exposed to sulphide above 20 mu M, CR... |
Tipo: Text |
Palavras-chave: ATP; AEC; Electron transport system; Succcinate; Alanine; Phosphoenolpyruvate carboxykinase; Pyruvate kinase; Oxygen consumption; Clearance rate; Crassostrea gigas; Sulphide; Oyster. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-3924.pdf |
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Prudence, Marie; Moal, Jeanne; Boudry, Pierre; Daniel, Jean-yves; Quere, Claudie; Jeffroy, Fanny; Mingant, Christian; Ropert, Michel; Bedier, Edouard; Van Wormhoudt, A; Samain, Jean-francois; Huvet, Arnaud. |
This study investigated the non-neutrality of genetic polymorphism in two alpha-amylase genes (AMYA and AMYB) in the oyster Crassostrea gigas. Bi-parental oyster families, bred to be polymorphic for markers in these genes, were monitored for growth and survival for 1 year under standard culture conditions in two French production sites. Within-family genotype frequencies indicated that the two amylase genes were closely linked (c. 1.7 cM). Within two of three families, significant differences in growth were observed between genotypes at one of the two production sites, suggesting that this polymorphism is not neutral and might be under selection because of its role in digestive function. Estimated daily yields were different between amylase genotypes,... |
Tipo: Text |
Palavras-chave: Growth; Genotype; Digestive enzyme; Bivalve; Alpha amylase. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-1691.pdf |
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Registros recuperados: 23 | |
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