Consulta: creatorFacets:"Fievet, Julie"
Registros recuperados: 16
Data/hora: 16/06/2024 15:57:06

Characterization of molecular processes involved in the pearl formation in Pinctada margaritifera for a sustainable development of pearl farming industry in French Polynesia
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: 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

Probiotic treatment of live food organisms for Atlantic bluefin tuna larvae: microbiological &amp; immunological criteria
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Coves, Denis; De Vogue, Benoist; Desbruyeres, Elisabeth; Dhormes, Benoit; Fievet, Julie; Huelvan, Christine; Lallement, Stephane; Le Gall, Marie-madeleine; Ruelle, Francois; Vidal, Marie-odile; Castex, M.; Mazurais, David; Cahu, Chantal; Gatesoupe, François-joel.
Tipo: Text
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00051/16189/13702.pdf

A relationship between antimicrobial peptide gene expression and capacity of a selected shrimp line to survive a Vibrio infection
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: 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

Characterization of a defensin from the oyster Crassostrea gigas - Recombinant production, folding, solution structure, antimicrobial activities, and gene expression
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: 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

Influence of water temperature and food on the last stages of cultured pearl mineralization from the black-lip pearl oyster Pinctada margaritifera
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Latchere, Oihana; Mehn, Vincent; Gaertner-mazouni, Nabila; Le Moullac, Gilles; Fievet, Julie; Belliard, Corinne; Cabral, Philippe; Saulnier, Denis.
Environmental parameters, such as food level and water temperature, have been shown to be major factors influencing pearl oyster shell growth and molecular mechanisms involved in this biomineralization process. The present study investigates the effect of food level (i.e., microalgal concentration) and water temperature, in laboratory controlled conditions, on the last stages of pearl mineralization in order to assess their impact on pearl quality. To this end, grafted pearl oysters were fed at different levels of food and subjected to different water temperatures one month prior to harvest to evaluate the effect of these factors on 1) pearl and shell deposition rate, 2) expression of genes involved in biomineralization in pearl sacs, 3) nacre...
Tipo: Text
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00428/54007/55223.pdf

Oyster hemocytes express a proline-rich peptide displaying synergistic antimicrobial activity with a defensin
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Gueguen, Yannick; Romestand, Bernard; Fievet, Julie; Schmitt, Paulina; Destoumieux Garzon, Delphine; Franck, Vandenbulcke; Philippe, Bulet; Bachere, Evelyne.
A cDNA sequence that encodes a 61-amino acid polypeptide precursor with homologies to proline-rich antimicrobial peptides (AMPs) was identified in the oyster Crassostrea gigas. After release of a hydrophobic signal peptide. the resulting 37-amino acid peptide, Cg-Prp, is composed of an acidic region and a cationic proline-rich region. To evaluate the biological properties of Cg-Prp, multiple proline-rich peptides corresponding to putative processing of the full-length Cg-Prp were synthesized. A limited antimicrobial activity was observed for two of them, which also showed strong synergistic antimicrobial activity with Cg-Def, a defensin from C gigas. To our knowledge, this is the first evidence of synergy between a defensin and another AMP in an...
Tipo: Text
Palavras-chave: Antimicrobial peptide; Mollusk; Synergy; Invertebrate; Innate immunity; Pacific oyster.
Ano: 2009
URL: http://archimer.ifremer.fr/doc/2009/publication-6232.pdf

Influence of preoperative food and temperature conditions on pearl biogenesis in Pinctada margaritifera
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Latchere, Oihana; Le Moullac, Gilles; Gaertner-mazouni, Nabila; Fievet, Julie; Magre, Kevin; Saulnier, Denis.
Trophic conditions and water temperature strongly influence bivalve physiological processes and metabolism. In black-lip pearl oyster Pinctada margaritifera, these parameters have been shown to affect shell biomineralization. The present study investigated the effect of preoperative food level (i.e., microalgal concentration) and temperature on pearl biomineralization. Donor and recipient oysters were conditioned at different levels of food and temperature during the preoperative phase to evaluate the influence of these factors on 1) pearl retention rate (grafting success), 2) expression of genes involved in biomineralization in the mantle and pearl sac and 3) pearl quality traits. Our study confirmed the influence of both microalgal concentration and...
Tipo: Text
Palavras-chave: Pinctada margaritifera; Cultured pearl; Biomineralization; Environment; Gene expression; Pearl quality.
Ano: 2017
URL: http://archimer.ifremer.fr/doc/00387/49799/50367.pdf

Evidence of a bactericidal permeability increasing protein in an invertebrate, the Crassostrea gigas Cg-BPI
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: 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

Evidence in oyster of a plasma extracellular superoxide dismutase which binds LPS
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Gonzalez, Marcelo; Romestand, Bernard; Fievet, Julie; Huvet, Arnaud; Lebart, M; Gueguen, Yannick; Bachere, Evelyne.
We have characterized in the oyster Crassostrea gigas an extracellular superoxide dismutase (Cg-EcSOD) which appears to bind lipopolysaccharides (LPS). The protein has been purified from the oyster plasma and identified as a Cu/ZnSOD according to its N-terminal sequencing and biological activity. Cg-EcSOD expression and synthesis are restricted to hemocytes as revealed by in situ hybridization and immunocytochemistry. Cg-EcSOD-expressing hemocytes were seen in blood circulation, in connective tissues, and closely associated to endothelium blood vessels. Cg-EcSOD presents in its amino acid sequence a LPS-binding motif found in the endotoxin receptor CD14 and we show that the protein displays an affinity to Escherichia coli bacteria and with LPS and Lipid A....
Tipo: Text
Palavras-chave: Beta integrin; Oxidative burst; Hemocyte; Crassostrea gigas; Invertebrate; Mollusc bivalve.
Ano: 2005
URL: http://archimer.ifremer.fr/doc/2005/publication-3583.pdf

Effect of dietary water content on European sea bass (Dicentrarchus labrax) growth and disease resistance
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Przybyla, Cyrille; Fievet, Julie; Callier, Myriam; Blancheton, Jean-paul.
The effect of dietary water content on Dicentrarchus labrax growth parameters and resistance to Vibrio anguillarum infection was investigated using commercial pellets with identical energy contents and different moisture levels. The first experiment hypothesis was that moisturizing pelleted ration can have an impact on Dicentrarchus labrax growth performance by the osmoregulation energy cost reduction. In a second time, the experiment explores the effect of water addition in pellets on the fish resistance to a disease. A specific device was built to uniformly moisturize dry pellets to different moisture levels, i.e. 8%, 20%, 40% and 60%. After an acclimation period and a 54-day rearing period, the control fish had grown from 72.7 +/- 17.9 g to 133.3 +/-...
Tipo: Text
Palavras-chave: Fish aquaculture; Dietary moisture content; Feed pellets; Fish growth; Immunity; Dicentrarchus labrax; Vibrio anguillarum.
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00248/35927/34446.pdf

Functional Divergence in Shrimp Anti-Lipopolysaccharide Factors (ALFs): From Recognition of Cell Wall Components to Antimicrobial Activity
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: 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
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00160/27077/25236.pdf

Feed demand behavior in sea bass juveniles: Effects on individual specific growth rate variation and health (inter-individual and inter-group variation)
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Millot, Sandie; Begout, Marie-laure; Person, Jeannine; Breuil, Gilles; Di Poi, C; Fievet, Julie; Pineau, Philippe; Roue, M; Severe, Armelle.
Feeding motivation is one major indicator of fish welfare and an investigation on the link between feed demand, growth and physiological variables in sea bass juveniles was developed. A computerized on-demand feeding system coupled with a PIT tag monitoring device was used to continuously record for 219 days the triggering activity of 150 individuals (initial average body weight 131.6 +/- 1.80 g and coefficient of variation 16.8%). Each group was held in 400 1 tanks at 22.2 +/- 1.5 degrees C and light regime was 16:8 LD. In all the tanks, 89% of the fish actuated the trigger, but only two or three fish accounted for 45% of the total triggering activity. These few high-triggering individuals had a transient higher growth i.e. at the time an individual was...
Tipo: Text
Palavras-chave: Welfare; Social interaction; Growth; Feeding activity.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-3738.pdf

Effect of electrolysis treatment on the biomineralization capacities of pearl oyster Pinctada margaritifera juveniles
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Latchere, Oihana; Fievet, Julie; Lo, Cedrik; Schneider, Denis; Dieu, Stephanie; Cabral, Philippe; Belliard, Corinne; Ky, Chin-long; Gueguen, Yannick; Saulnier, Denis.
The present study investigated the effect of electrolysis on the biomineralization capacities of juveniles of the mollusk Pinctada margaritifera for the first time. Size-selected individuals from two groups, “Medium” and “Large”, from a multi-parental family produced in a hatchery system were subjected to electrolysis under a low voltage current over a nine-week experimental period. The growth of the juveniles was individually monitored and assessed weekly by wet weight and shell height measurements. At the end of the experiment, mantle tissue was sampled for biomineralization-related gene expression analysis. Electrolysis significantly increased pearl oyster growth in terms of shell height and wet weight for Large juveniles from the 5th and the 2nd week,...
Tipo: Text
Palavras-chave: Pearl oyster; Pinctada margaritifera; Electrolysis; Biomineralization; Gene expression.
Ano: 2016
URL: http://archimer.ifremer.fr/doc/00343/45410/44924.pdf

Big Defensins, a Diverse Family of Antimicrobial Peptides That Follows Different Patterns of Expression in Hemocytes of the Oyster Crassostrea gigas
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Rosa, Rafael D.; Santini, Adrien; Fievet, Julie; Bulet, Philippe; Destoumieux-garzon, Delphine; Bachere, Evelyne.
Background: Big defensin is an antimicrobial peptide composed of a highly hydrophobic N-terminal region and a cationic C-terminal region containing six cysteine residues involved in three internal disulfide bridges. While big defensin sequences have been reported in various mollusk species, few studies have been devoted to their sequence diversity, gene organization and their expression in response to microbial infections. Findings: Using the high-throughput Digital Gene Expression approach, we have identified in Crassostrea gigas oysters several sequences coding for big defensins induced in response to a Vibrio infection. We showed that the oyster big defensin family is composed of three members (named Cg-BigDef1, Cg-BigDef2 and Cg-BigDef3) that are...
Tipo: Text
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00050/16096/13576.pdf

Impact of pCO2 on the energy, reproduction and growth of the shell of the pearl oyster Pinctada margaritifera
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: 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

Fish growth and health aspects of sea bass (Dicentrarchus labrax) reared in standard vs. high rate algal pond recirculation systems
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Mladineo, Ivona; Bocina, Ivana; Przybyla, Cyrille; Fievet, Julie; Blancheton, Jean-paul.
Recirculation aquaculture system (RAS) is the type of land-based aquaculture production that interferes the least with the environment, particularly due to low effluent volume and overall water requirement. Water reuse, sometimes limited by the accumulation of waste products excreted by fish, can be improved by incorporating another biotechnical component in the form of high rate algal pond (RAS+HRAP), thus adding to the economy and self sustainability of the system. Our goal was to evaluate whether rearing fish for 1 year in a RAS or RAS+HRAP led to differences in fish production and health, by assessing: (1) fish growth; (2) impact on the morphological structure of sea bass target tissues (liver, kidney, and spleen); (3) susceptibility to monogenean...
Tipo: Text
Palavras-chave: Health; High rate algal pond; Recirculation; Sea bass.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00011/12228/9010.pdf