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Didier Jollivet,
Jean Mary,
Nicolas Gagnière,
Arnaud Tanguy,
Eric Fontanillas, Isabelle Boutet,
Stéphane Hourdez,
Béatrice Segurens,
Jean Weissenbach,
Olivier Poch,
Odile Lecompte
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ABSTRACT: Taking advantage of the massive genome sequencing effort made on thermophilic prokaryotes, thermal adaptation has been extensively studied by analysing amino acid replacements and codon usage in these unicellular organisms. In most cases, adaptation to thermophily is associated with greater residue hydrophobicity and more charged residues. Both of these characteristics are positively correlated with the optimal growth temperature of prokaryotes. In contrast, little information has been collected on the molecular 'adaptive' strategy of thermophilic eukaryotes. The Pompeii worm A. pompejana, whose transcriptome has recently been sequenced, is currently considered as the most thermotolerant eukaryote on Earth, withstanding the greatest thermal and chemical ranges known. We investigated the amino-acid composition bias of ribosomal proteins in the Pompeii worm when compared to other lophotrochozoans and checked for putative adaptive changes during the course of evolution using codon-based Maximum likelihood analyses. We then provided a comparative analysis of codon usage and amino-acid replacements from a greater set of orthologous genes between the Pompeii worm and Paralvinella grasslei, one of its closest relatives living in a much cooler habitat. Analyses reveal that both species display the same high GC-biased codon usage and amino-acid patterns favoring both positively-charged residues and protein hydrophobicity. These patterns may be indicative of an ancestral adaptation to the deep sea and/or thermophily. In addition, the Pompeii worm displays a set of amino-acid change patterns that may explain its greater thermotolerance, with a significant increase in Tyr, Lys and Ala against Val, Met and Gly. Present results indicate that, together with a high content in charged residues, greater proportion of smaller aliphatic residues, and especially alanine, may be a different path for metazoans to face relatively 'high' temperatures and thus a novelty in thermophilic metazoans.
PLoS ONE 01/2012; 7(2):e31150. · 4.09 Impact Factor
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ABSTRACT: The deep-sea hydrothermal vent mussel Bathymodiolus azoricus harbors thiotrophic and methanotrophic symbiotic bacteria in its gills. While the symbiotic relationship between this hydrothermal mussel and these chemoautotrophic bacteria has been described, the molecular processes involved in the cross-talking between symbionts and host, in the maintenance of the symbiois, in the influence of environmental parameters on gene expression, and in transcriptome variation across individuals remain poorly understood. In an attempt to understand how, and to what extent, this double symbiosis affects host gene expression, we used a transcriptomic approach to identify genes potentially regulated by symbiont characteristics, environmental conditions or both. This study was done on mussels from two contrasting populations.
Subtractive libraries allowed the identification of about 1000 genes putatively regulated by symbiosis and/or environmental factors. Microarray analysis showed that 120 genes (3.5% of all genes) were differentially expressed between the Menez Gwen (MG) and Rainbow (Rb) vent fields. The total number of regulated genes in mussels harboring a high versus a low symbiont content did not differ significantly. With regard to the impact of symbiont content, only 1% of all genes were regulated by thiotrophic (SOX) and methanotrophic (MOX) bacteria content in MG mussels whereas 5.6% were regulated in mussels collected at Rb. MOX symbionts also impacted a higher proportion of genes than SOX in both vent fields. When host transcriptome expression was analyzed with respect to symbiont gene expression, it was related to symbiont quantity in each field.
Our study has produced a preliminary description of a transcriptomic response in a hydrothermal vent mussel host of both thiotrophic and methanotrophic symbiotic bacteria. This model can help to identify genes involved in the maintenance of symbiosis or regulated by environmental parameters. Our results provide evidence of symbiont effect on transcriptome regulation, with differences related to type of symbiont, even though the relative percentage of genes involved remains limited. Differences observed between the vent site indicate that environment strongly influences transcriptome regulation and impacts both activity and relative abundance of each symbiont. Among all these genes, those participating in recognition, the immune system, oxidative stress, and energy metabolism constitute new promising targets for extended studies on symbiosis and the effect of environmental parameters on the symbiotic relationships in B. azoricus.
BMC Genomics 01/2011; 12:530. · 4.07 Impact Factor
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ABSTRACT: Pesticide run-off into the ocean represents a potential threat to marine organisms, especially bivalves living in coastal environments. However, little is known about the effects of environmentally relevant concentrations of pesticides at the individual level. In this study, the suppression subtractive hybridisation technique was used to discover the main physiological function affected by a cocktail of three pesticides (lindane, metolachlor and carbofuran) in the Pacific oyster Crassostrea gigas. Two oyster populations exposed to different pollution levels in the wild were investigated. The pesticide concentrations used to induce stress were close to those found in the wild. In a time course experiment, the expression of three genes implicated in iron metabolism and oxidative stress as well as that of two ubiquitous stress proteins was examined. No clear regulation of gene or protein expression was found, potentially due to a low-dose effect. However, we detected a strong site- and organ-specific response to the pesticides. This study thus (1) provides insight into bivalve responses to pesticide pollution at the level of the transcriptome, which is the first level of response for organisms facing pollution, and (2) raises interesting questions concerning the importance of the sites and organs studied in the toxicogenomic field.
Journal of Experimental Biology 12/2010; 213(Pt 23):4010-7. · 3.00 Impact Factor
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Nicolas Gagnière,
Didier Jollivet, Isabelle Boutet,
Yann Brélivet,
Didier Busso,
Corinne Da Silva,
Françoise Gaill,
Dominique Higuet,
Stéphane Hourdez,
Bernard Knoops, [......],
Jean-François Rees,
Béatrice Segurens,
Bruce Shillito,
Arnaud Tanguy,
Jean-Claude Thierry,
Jean Weissenbach,
Patrick Wincker,
Franck Zal,
Olivier Poch,
Odile Lecompte
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ABSTRACT: Alvinella pompejana is a representative of Annelids, a key phylum for evo-devo studies that is still poorly studied at the sequence level. A. pompejana inhabits deep-sea hydrothermal vents and is currently known as one of the most thermotolerant Eukaryotes in marine environments, withstanding the largest known chemical and thermal ranges (from 5 to 105°C). This tube-dwelling worm forms dense colonies on the surface of hydrothermal chimneys and can withstand long periods of hypo/anoxia and long phases of exposure to hydrogen sulphides. A. pompejana specifically inhabits chimney walls of hydrothermal vents on the East Pacific Rise. To survive, Alvinella has developed numerous adaptations at the physiological and molecular levels, such as an increase in the thermostability of proteins and protein complexes. It represents an outstanding model organism for studying adaptation to harsh physicochemical conditions and for isolating stable macromolecules resistant to high temperatures.
We have constructed four full length enriched cDNA libraries to investigate the biology and evolution of this intriguing animal. Analysis of more than 75,000 high quality reads led to the identification of 15,858 transcripts and 9,221 putative protein sequences. Our annotation reveals a good coverage of most animal pathways and networks with a prevalence of transcripts involved in oxidative stress resistance, detoxification, anti-bacterial defence, and heat shock protection. Alvinella proteins seem to show a slow evolutionary rate and a higher similarity with proteins from Vertebrates compared to proteins from Arthropods or Nematodes. Their composition shows enrichment in positively charged amino acids that might contribute to their thermostability. The gene content of Alvinella reveals that an important pool of genes previously considered to be specific to Deuterostomes were in fact already present in the last common ancestor of the Bilaterian animals, but have been secondarily lost in model invertebrates. This pool is enriched in glycoproteins that play a key role in intercellular communication, hormonal regulation and immunity.
Our study starts to unravel the gene content and sequence evolution of a deep-sea annelid, revealing key features in eukaryote adaptation to extreme environmental conditions and highlighting the proximity of Annelids and Vertebrates.
BMC Genomics 11/2010; 11:634. · 4.07 Impact Factor
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ABSTRACT: Hydrothermal vent mussels belonging to the genus Bathymodiolus are distributed worldwide and dominate communities at shallow Atlantic hydrothermal sites. While organisms inhabiting coastal ecosystems are subjected to predictable oscillations of physical and chemical variables owing to tidal cycles, the vent mussels sustain pronounced temperature changes over short periods of time, correlated to the alternation of oxic/anoxic phases. In this context, we focused on the short-term adaptive response of mussels to temperature change at a molecular level. The mRNA expression of 23 genes involved in various cell functions of the vent mussel Bathymodiolus azoricus was followed after heat shocks for either 30 or 120 min, at 25 and 30 degrees C over a 48 h recovery period at 5 degrees C. Mussels were genotyped at 10 enzyme loci to explore a relationship between natural genetic variation, gene expression and temperature adaptation. Results indicate that the mussel response to increasing temperature is a depression in gene expression, such a response being genotypically correlated at least for the Pgm-1 locus. This suggests that an increase in temperature could be a signal triggering anaerobiosis for B. azoricus or this latter alternatively behaves more like a 'cold' stenotherm species, an attribute more related to its phylogenetic history, a cold seeps/wood fall origin.
Proceedings of the Royal Society B: Biological Sciences 07/2009; 276(1670):3071-9. · 5.41 Impact Factor
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ABSTRACT: Hydrothermal vents and cold seeps represent oases of life in the deep-sea environment, but are also characterized by challenging physical and chemical conditions. The effect of temperature fluctuations on vent organisms in their habitat has not been well explored, in particular at a molecular level, most gene expression studies being conducted on coastal marine species. In order to better understand the response of hydrothermal organisms to different temperature regimes, differentially expressed genes (obtained by a subtractive suppression hybridization approach) were identified in the mussel Bathymodiolus thermophilus and the annelid Paralvinella pandorae irlandei to characterize the physiological processes involved when animals are subjected to long term exposure (2 days) at two contrasting temperatures (10 degrees versus 20 degrees C), while maintained at in situ pressures. To avoid a potential effect of pressure, the experimental animals were initially thermally acclimated for 24 hours in a pressurized vessel.
For each species, we produced two subtractive cDNA libraries (forward and reverse) from sets of deep-sea mussels and annelids exposed together to a thermal challenge under pressure. RNA extracted from the gills, adductor muscle, mantle and foot tissue were used for B. thermophilus. For the annelid model, whole animals (small individuals) were used. For each of the four libraries, we sequenced 200 clones, resulting in 78 and 83 unique sequences in mussels and annelids (about 20% of the sequencing effort), respectively, with only half of them corresponding to known genes. Real-time PCR was used to validate differentially expressed genes identified in the corresponding libraries. Strong expression variations have been observed for some specific genes such as the intracellular hemoglobin, the nidogen protein, and Rab7 in P. pandorae, and the SPARC protein, cyclophilin, foot protein and adhesive plaque protein in B. thermophilus.
Our results indicate that mussels and worms are not responding in the same way to temperature variations. While the results obtained for the mussel B. thermophilus seem to indicate a metabolic depression (strong decrease in the level of mRNA expression of numerous genes) when temperature increased, the annelid P. pandorae mainly displayed a strong regulation of the mRNA encoding subunits and linkers of respiratory pigments and some proteins involved in membrane structure. In both cases, these regulations seem to be partly due to a possible cellular oxidative stress induced by the simulated thermal environment (10 degrees C to 20 degrees C). This work will serve as a starting point for studying the transcriptomic response of hydrothermal mussels and annelids in future experiments in response to thermal stress at various conditions of duration and temperature challenge.
BMC Genomics 06/2009; 10:222. · 4.07 Impact Factor
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ABSTRACT: Numerous studies have investigated the reproduction mechanisms in mollusc species at a biochemical and physiological level; few have described these mechanisms at a molecular level, despite great commercial interest in several mollusc species. We investigated genes involved in gonad maturation of the marine scallop Argopecten purpuratus. A cDNA library was made from gonad tissue. After sequence analysis, 418 unique genes were characterized, of these, about 80% were of unknown function. Among the identified sequences, we analyzed the mRNA expression by real-time PCR of 7 genes involved in reproduction mechanisms, either directly: testis-specific serine/threonine-protein kinase (TSSK), vitellogenin (Vg), and spermatogenesis and centriole associated 1 (SCA) or indirectly: calcineurin A (CNA), centrin, RNA-specific adenosine deaminase (ADAR), and cytidine deaminase (CDA). The real-time PCR analyses were conducted on different tissues of mature and immature scallops (testis, ovary, immature gonad, gill, digestive gland and mantle). The genes studied, presented (1) a strong tissue-dependent expression pattern (higher expression in gonad tissues than in all other tissues) and (2) a sex- and maturation-specific expression pattern (except centrin). This is the first time that the expression of specific genes involved in reproduction mechanisms in a marine mollusc has been described at the molecular level.
Gene 02/2008; 407(1-2):130-8. · 2.34 Impact Factor
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Arnaud Tanguy,
Nicolas Bierne,
Carlos Saavedra,
Benjamin Pina,
Evelyne Bachère,
Michael Kube,
Eric Bazin,
François Bonhomme,
Pierre Boudry,
Viviane Boulo, [......],
Didier Jollivet,
Sven Klages,
Sylvie Lapègue,
Ricardo Leite,
Jeanne Moal,
Dario Moraga,
Richard Reinhardt,
Jean-François Samain,
Eleftherios Zouros,
Adelino Canario
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ABSTRACT: The generation of EST information is an essential step in the genomic characterisation of species. In the context of the European Network Marine Genomics, a common goal was to significantly increase the amount of ESTs in commercial marine mollusk species and more specifically in the less studied but ecologically and commercially important groups, such as mussel and clam genera. Normalized cDNA libraries were constructed for four different relevant bivalves species (Crassostrea gigas, Mytilus edulis, Ruditapes decussatus and Bathymodiolus azoricus), using numerous tissues and physiological conditions. In this paper, we present the analysis of the 13,013 expressed sequence tags (ESTs) generated. Each EST library was independently assembled and 1300-3000 unique sequences were identified in each species. For the different species, functional categories could be assigned to only about 16 to 27% of ESTs using the GO annotation tool. All sequences have been incorporated into a publicly available database and form the basis for subsequent microarray design, SNP detection and polymorphism analysis, and the placement of novel markers on genetic linkage maps.
Gene 02/2008; 408(1-2):27-36. · 2.34 Impact Factor
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ABSTRACT: Phosphoglucomutase is a key enzyme in glycolysis and has been widely studied in vertebrates and some invertebrates but no molecular information is available in marine invertebrates despite the importance of this marker in ecological and genetical studies. In this work, we isolated a cDNA and the corresponding genomic sequence that encode PGM-2 locus in the Pacific oyster Crassostrea gigas. We used sequences drawn from the database to construct an evolutionary framework for examining the position of mollusc PGM sequences among prokaryotic and eukaryotic homologues and showed that oyster PGM gene organization was closer to vertebrates PGM genes than other invertebrates as previously found in other Lophotrochozoa species. We also investigated PGM mRNA expression in oyster tissues in response to xenobiotics (i.e hydrocarbons and pesticides). The results obtained showed that PGM mRNA expression is mostly up-regulated in the first steps of the response to pollutant exposure and is xenobiotic-dependent.
Gene 12/2006; 382:20-7. · 2.34 Impact Factor
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ABSTRACT: As a part of the multidisciplinary program Biological Effects of Environmental Pollution in Marine Coastal Ecosystems of the European Commission, this study aimed to validate immunological alterations as biomarkers of exposure to chemical contamination in polluted areas of Western Mediterranea. The status of the immune system has been assessed in mussels (Mytilus galloprovincialis) by measuring several immunopathological and immunocompetence parameters. Alterations of total hemocyte counts, lysosomal stability, and phagocytosis were among the most reliable effects observed in polluted sites and suggested immunosuppressive conditions in contaminated mussels. An immunotoxicological index was calculated from the set of individual data. By providing a single value per sampling station to score immunological alterations in mussels, this novel approach allowed recognition of a gradient of perturbation correlated to pollution intensity in two of the three sites monitored. Processing a set of biological parameters by this method was found to increase the ecotoxicological relevance of such multiparametric studies for the assessment of chemical contamination in coastal waters.
Ecotoxicology and Environmental Safety 04/2006; 63(3):393-405. · 2.29 Impact Factor
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ABSTRACT: Quantitative real-time polymerase chain reaction (PCR) was used to compare for the first time the differential expression of metallothionein (MT) isoform genes, together with biosynthesis of the total MT proteins, in the gills of triploid and diploid juvenile Pacific oyster Crassostrea gigas in response to cadmium (Cd) and zinc (Zn) exposure. Oysters were exposed to Cd (0.133 microM), Zn (15.3 microM), and Cd+Zn for 14 d. Results showed similar response capacities to metal exposures in the two populations. No significant difference was revealed in terms of MT gene expression, MT protein synthesis, and Cd accumulation. However, triploid oysters bioaccumulated Zn 30% less efficiently than diploid oysters. Among the three MT isoform genes, CgMT2 appeared to be more expressed than CgMT1, whereas CgMT3 appeared to be anecdotal (10(6) times lower than CgMT2). CgMT2 and CgMT1 gene expression levels were increased sevenfold in the presence of Cd, whereas Zn appeared to have no effect. A twofold increase in MT protein levels occurred in response to Cd exposure. Discrepancies between mRNA and protein levels suggest that in C. gigas MT are regulated at the transcriptional level, as well as at the translational level.
Environmental Toxicology and Chemistry 03/2006; 25(2):412-8. · 2.81 Impact Factor
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ABSTRACT: Localization of heat shock proteins (HSPs) and metallothioneins (MTs) was investigated in a marine bivalve (Crassostrea gigas) by immunohistochemical methods. Differential protein expression was demonstrated in digestive gland, gonad and gills, using a polyclonal antibody against C. gigas proteins. Application of this technique showed the cellular and tissue immunolabelling specificity of the two proteins. HSPs and MTs were localized in the epithelium of the digestive gland and gills in contact with the palleal compartment. For the first time, localization of MTs was observed in mature gametes of bivalve molluscs. Our results establish a basis for the use of immmunodetection techniques to study the tissue-specific localization of stress proteins in marine bivalves exposed to metal stress.
Comparative Biochemistry and Physiology Part C Toxicology & Pharmacology 07/2005; 141(2):151-6. · 2.62 Impact Factor
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ABSTRACT: A partial cDNA encoding cytosolic aspartate aminotransferase (AST) (EC 2.6.1.1) was isolated from a Crassostrea gigas digestive gland library. This sequence was used to design specific primers to amplify the AST genomic sequence. We obtained a complete gene, 5054 bp in length, encoding cytosolic AST and containing a 404 amino acid open reading frame. Phylogenetic analysis showed that C. gigas AST sequence constitutes a branch distinct from homologous sequences from other invertebrate groups. We also investigated AST mRNA expression in different tissues of oysters exposed to hydrocarbons, pesticides, hypoxia and hypo-salinity stress. The results showed that AST expression responds to hydrocarbon exposure, hypoxia and salinity stress, but not to pesticide exposure in an organ and time-specific manner. Use of AST as a potential molecular biomarker for monitoring of disturbed ecosystems is discussed.
Comparative Biochemistry and Physiology Part C Toxicology & Pharmacology 02/2005; 140(1):69-78. · 2.62 Impact Factor
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ABSTRACT: In this study, we characterized the full-length cDNA and genomic sequence of the gene encoding cytosolic glutamine synthetase (CgGSII) in the Pacific oyster, Crassostrea gigas. A phylogenetic analysis of GS sequences showed that CgGS clustered with the invertebrate group as expected. We analyzed the expression of mRNA CgGSII using RT-PCR to follow the expression of this gene in gills and digestive gland of oysters exposed, under experimental conditions, to hypoxia and to several contaminants (hydrocarbons and two pesticide treatments, glyphosate and a mixture of atrazine, diuron and isoproturon). We also investigated the expression of CgGSII in different developmental stages of C. gigas. Our results show that CgGSII expression was highly regulated in xenobiotic-exposed oysters compared to the control for all the treatments. Likewise, CgGSII expression was highly regulated according to the developmental stage of C. gigas. Finally, use of CgGSII as a possible marker to monitor xenobiotic exposure in disturbed ecosystems is discussed.
Biochimica et Biophysica Acta 02/2005; 1681(2-3):116-25. · 4.66 Impact Factor
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ABSTRACT: The effects of pesticide contamination on the metabolism of marine molluscs are poorly documented. We investigated the response of a marine bivalve, the Pacific oyster, Crassostrea gigas, using a suppression subtractive hybridization method to identify up- and down-regulated genes after a 30-day exposure period to herbicides (a cocktail of atrazine, diuron and isoproturon, and to the single herbicide glyphosate). A total of 137 unique differentially expressed gene sequences was identified, as well as their associated physiological process. The expression of 18 of these genes was analyzed by RT-PCR under laboratory experimental conditions. The metabolic functions they are associated with include xenobiotic detoxification, energy production, immune system response and transcription. This study provides a preliminary basis for studying the response of marine bivalves to long-term herbicide exposure in terms of regulated gene expression and characterizes new potential genetic markers of herbicide contamination.
FEBS Journal 02/2005; 272(2):390-403. · 3.79 Impact Factor
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ABSTRACT: Marine bivalve metabolism can be perturbed by hydrocarbon and pesticide pollution in coastal ecosystems. In this study, in the Pacific oyster, Crassostrea gigas, full-length cDNAs encoding two non-P450 phase I enzymes, flavin-containing monooxygenase 2 (FMO-2) and monamine oxidase A (MAO A), were characterized. Both sequences contained the co-factor fixation motifs characteristic of their respective enzyme families. Using reverse transcription polymerase chain reaction (RT-PCR), the messenger RNA (mRNA) transcription levels of these two enzymes in tissues of oysters exposed, under experimental conditions, to hydrocarbons and two pesticide treatments were investigated. The pesticide treatments were exposure to either glyphosate or to a mixture composed of atrazine, diuron and isoproturon. The results showed a strong differential expression of FMO-2 and MAO A that was both tissue-specific as well as time- and treatment-dependent. It was also clearly demonstrated that the transcription levels of MAO A (generally considered a constitutive enzyme without external regulation) were induced by hydrocarbons and pesticides in digestive gland and inhibited by pesticides in gill tissue. Furthermore, the transcription levels of FMO-2 and MAO A mRNA in digestive gland might be useful as a marker of hydrocarbon or pesticide exposure in monitoring programs.
Biochimica et Biophysica Acta 08/2004; 1679(1):29-36. · 4.66 Impact Factor
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ABSTRACT: Hydrocarbon contamination perturbs the metabolism of the marine bivalve Crassostrea gigas. To understand the response of this organism to hydrocarbon exposure, a suppression subtractive hybridisation method was employed to characterise up- and down-regulated genes during hydrocarbon exposure. The number of differentially expressed gene sequences obtained via this method was 258. The expression of genes involved in hydrocarbon detoxification (cytochrome p4501A1-like protein, cytochrome b(5), flavin-containing monooxygenase 2 and glutathione S-transferase omega class), protection against oxidative stress (copper/zinc superoxide dismutase) and cell protection (heat shock protein 70 family) was analysed by RT-PCR. An increase in the mRNA level of all genes studied was observed. A quantification of HSP70 by Enzyme Linked Immunosorbent Assay (ELISA) showed a significant increase of this protein during exposure. This study provides a basis for studying hydrocarbon detoxification processes in marine bivalves, especially C. gigas.
Gene 04/2004; 329:147-57. · 2.34 Impact Factor
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ABSTRACT: The heat shock protein 70 family is composed of both environmentally inducible (Hsp) and constitutively expressed (Hsc) members. We sequenced two genes encoding Hsp70 and Hsc70 in the European flat oyster Ostrea edulis. The Oehsc70 gene contained introns, while the Oehsp70 gene did not. The corresponding amino acid sequences contained the characteristic motifs of the HSP70 family.
Aquatic Toxicology 11/2003; 65(2):221-5. · 3.76 Impact Factor
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ABSTRACT: The 70-kDa heat shock protein (Hsp) family is composed of both environmentally inducible (Hsp) and constitutively expressed (Hsc) family members. We sequenced 2 genes encoding an Hsp70 and an Hsc70 in the Pacific oyster Crassostrea gigas. The Cghsc70 gene contained introns, whereas the Cghsp70 gene did not. Moreover, the corresponding amino acid sequences of the 2 genes presented all the characteristic motifs of the Hsp70 family. We also investigated the expression of Hsp70 in tissues of oysters experimentally exposed to metal. A recombinant Hsc72 was used as an antigen to produce a polyclonal antibody to quantify soluble Hsp70 by enzyme-linked immunosorbent assay in protein samples extracted from oysters. Our results showed that metals (copper and cadmium) induced a decrease in cytosolic Hsp70 level in gills and digestive gland of oysters experimentally exposed to metal. These data suggest that metals may inhibit stress protein synthesis.
Cell Stress and Chaperones 02/2003; 8(1):76-85. · 3.01 Impact Factor
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ABSTRACT: A recombinant metallothionein CgMT1, from the Pacific oyster Crassostrea gigas, was synthesized and used as antigen in the development of antibodies and a specific enzyme-linked immunosorbent assay (ELISA). The ELISA showed that rabbit anti-CgMT1 IgG reacted with purified CgMT1 and MTs from other marine bivalves, indicating its suitability as a reagent to quantify MTs and for monitoring of metal contamination in field animals. Application of this assay to tissues excised from metal exposed C. gigas, showed that MT induction reached a saturation level in gills that was not observed in digestive gland. Quantification of MTs in gills and digestive gland of field-collected C. gigas showed that the MT level depended on the metal concentrations at the collection sites and may have been influenced by salinity variations at estuarine sites. Oysters from metal-contaminated estuarine sites showed lower MT concentrations than those from nonestuarine contaminated sites.
Environmental Toxicology and Chemistry 06/2002; 21(5):1009-14. · 2.81 Impact Factor
