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| Registros recuperados: 27 | |
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| Bouilly, Karine; Leitao, Alexandra; Mccombie, Helen; Chaves, R.; Guedes Pinto, H; Boudry, Pierre; Lapegue, Sylvie. |
| In the Pacific oyster, Crassostrea gigas hypodiploid aneuploid cells with 2n=19, 18 or 17 chromosomes have regularly been reported. There is a negative correlation between somatic aneuploidy and growth rate in oysters (Leitão et al., 2001a) as well as evidence for a genetic basis (Leitão et al., 2001b). Furthermore, non-random chromosome loss has been demonstrated in aneuploid karyotypes of C. gigas using the G-banding technique (Leitão et al., 2001c). This poster summarises different studies used to investigate the effects of the herbicide atrazine on the level of aneuploidy in this species |
| Tipo: Text |
Palavras-chave: Genetic; Aneuploidy; Toxicology; Impact; Atrazine; Crassostrea gigas; Pacific oysters. |
| Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/2004/acte-3489.pdf |
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| Sousa, Joana; Milan, Massimo; Bargelloni, Luca; Pauletto, Marianna; Matias, Domitilia; Joaquim, Sandra; Matias, Ana Margarete; Quillien, Virgile; Leitao, Alexandra; Huvet, Arnaud. |
| The European clam, Ruditapes decussatus is a species with a high commercial importance in Portugal and other Southern European countries. Its production is almost exclusively based on natural recruitment, which is subject to high annual fluctuations. Increased knowledge of the natural reproductive cycle of R. decussatus and its molecular mechanisms would be particularly important in providing new highly valuable genomic information for better understanding the regulation of reproduction in this economically important aquaculture species. In this study, the transcriptomic bases of R. decussatus reproduction have been analysed using a custom oligonucleotide microarray representing 51,678 assembled contigs. Microarray analyses were performed in four gonadal... |
| Tipo: Text |
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| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00188/29935/28623.pdf |
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| Matias, Domitilia; Joaquim, Sandra; Matias, Ana Margarete; Moura, Paula; Sousa, Joana; Sobral, Paula; Leitao, Alexandra. |
| The reproductive cycle, as well as its nutrient storage and utilization, of two populations of Ruditapes decussatus from the main production areas of this species: Ria de Aveiro and Ria Formosa Lagoon (Portugal) were studied here over a 24 month period (May 2010-April 2012). The reproductive cycle of both populations of R. decussatus followed an annual cyclicality that comprised a ripe stage in spring followed by a spawning period that began in late spring and extended throughout summer until early autumn. This extended and continuous spawning period may be an advantageous strategy for this species by ensuring a continuous supply of gametes. Moreover, R. decussatus can adopt different reproductive strategies depending on the geographical origin. The... |
| Tipo: Text |
Palavras-chave: European clam; Ruditapes decussatus; Reproductive cycle; Portuguese populations; Biochemical composition; Seasonal variations. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00152/26292/25461.pdf |
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| Batista, Frederico M.; Lopez-sanmartin, Monserrat; Boudry, Pierre; Navas, Jose I.; Ruano, Francisco; Renault, Tristan; Fonseca, Vera G.; Leitao, Alexandra. |
| Cytogenetic abnormalities associated with viral infections, including from viruses of the Herpesvirales order, have been reported in vertebrate species. Ostreid herpesvirus 1 (OsHV-1) has been detected worldwide during mortality outbreaks of the Pacific oyster Crassostrea gigas. On the other hand, a high proportion of aneuploid cells in somatic tissues have been observed in C. gigas. In this study, we analysed the putative association between aneuploidy levels and the detection of OsHV-1 in gills of C. gigas, the Portuguese oyster C. angulata and their F1 hybrids cultured in Ria Formosa (Portugal). OsHV-1 was detected by PCR in 5.4% of the total of oysters analysed (n = 111) namely in 11.1%, 8.0% and 1.7% of C. gigas, C. angulata and F1 hybrid... |
| Tipo: Text |
Palavras-chave: Aneuploidy; Ostreid herpesvirus 1; Oyster; Crassostrea. |
| Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00215/32581/35759.pdf |
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| Bouilly, Karine; Mccombie, Helen; Leitao, Alexandra; Lapegue, Sylvie. |
| Divers travaux menés depuis 1984 montrent qu’il existe, chez l’huître creuse Crassostrea gigas, des cellules montrant un nombre anormal de chromosomes (2n = 19, 18 ou même 17 au lieu de 2n = 20). Le niveau d’aneuploïdie est déterminé par le décompte des chromosomes à partir de suspensions cellulaires de tissu branchial. Le pourcentage de cellules aneuploïdes est toujours significativement supérieur dans les "lots de queue", c'est-à-dire les huîtres présentant des croissances plus faibles, et peut atteindre plus de 30 %. Cette corrélation négative entre l’aneuploïdie somatique et le taux de croissance a été décrite à de nombreuses reprises (Thiriot-Quiévreux et al., 1988, 1992 ; Leitão et al., 2001a ; Zouros et al., 1996). Bien que les causes... |
| Tipo: Text |
Palavras-chave: Génétique; Chromosomes; Aneuploïdie; Huîtres creuses; Crassostrea gigas. |
| Ano: 2002 |
URL: http://archimer.ifremer.fr/doc/00044/15475/12854.pdf |
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| Boudry, Pierre; Leitao, Alexandra; Mccombie, Helen; Thiriot-quievreux, Catherine. |
| Cytogenetic abnormalities arising both in mitosis and meiosis are known to be common in bivalves. Here we review result obtained from the observations of somatic aneuploidy in different populations of the commercially important Pacific oyster, Crassostrea gigas. The oysters studied were either (1) produced in IFREMER hatcheries between 1986 and 1999, (some of these were part of the EU funded programme GENEPHYS); or (2) collected from wild populations along the French Atlantic coast. Chromosome numbers were scored from 30 mitotic metaphases in gill tissue per individual studied. Aneuploid cells (2n - X) were observed in all the 13 populations studied. A highly significant negative correlation was observed between the level of aneuploidy and growth, i.e.... |
| Tipo: Text |
Palavras-chave: Growth; Genetic; Aneuploidy; Crassostrea gigas; Pacific oysters. |
| Ano: 2000 |
URL: http://archimer.ifremer.fr/doc/2000/acte-3446.pdf |
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| Bouilly, Karine; Leitao, Alexandra; Chaves, Raquel; Guedes Pinto, Henrique; Boudry, Pierre; Lapegue, Sylvie. |
| Aneuploidy has previously been observed in the Pacific oyster, Crassostrea gigas, and shown to be negatively correlated with growth. Moreover, a significant impact of atrazine exposure has been described in C. gigas, and persistence of that effect has been observed between generations. Evidence of differential chromosome loss has been demonstrated in aneuploid karyotypes of C. gigas using the G-banding technique. Pairs 1, 5, 9, and 10 are characterized by the loss of 1 chromosome. As restriction enzyme (RE) digestion chromosome banding allows a better identification of chromosome pairs, we used this technique to identify which chromosomes are affected when aneuploidy is increased by exposure to atrazine. The progeny of oysters contaminated by atrazine were... |
| Tipo: Text |
Palavras-chave: Crassostrea gigas; Pacific oyster; Restriction enzyme digestion chromosome banding; Atrazine; Aneuploidy; Crassostrea gigas; Huître creuse; Marquage chromosomique par digestion d'enzymes de restriction; Atrazine; Aneuploïdie. |
| Ano: 2005 |
URL: https://archimer.ifremer.fr/doc/2005/publication-654.pdf |
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| Heurtebise, Serge; Boutet, Isabelle; Verden, B.; Lapegue, Sylvie; Leitao, Alexandra; Thiriot-quievreux, Catherine; Garica, P.; Boudry, Pierre. |
| Mangrove oysters include various species that are also present on different coasts. In the southern part of the Atlantic Ocean, Crassostrea rhizophorae has been observed along the southern coast of America and Crassostrea gasar along the western coast of Africa. Fifteen populations of these oysters were sampled from these two geographic areas. Their polymorphism was studied on the 16S mitochondrial fragment both by par sequencing and RFLP analysis. Some samples' caryotype were also analysed. Two haplotypes were identified: C. gasar was found in Africa, but also for the first time in South America, whereas C. rhizophorae was only found on the coasts of South America. |
| Tipo: Text |
Palavras-chave: Crassostrea rhizophorae; Crassostrea gasar; Huîtres; Génétique; Phylogéographie. |
| Ano: 2001 |
URL: http://archimer.ifremer.fr/doc/2001/acte-3278.pdf |
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| Grade, Ana; Chairi, Hicham; Lallias, Delphine; Power, Deborah M.; Ruano, Francisco; Leitao, Alexandra; Drago, Teresa; King, Jonathan W.; Boudry, Pierre; Batista, Frederico M.. |
| It is commonly presumed that the Portuguese oyster Crassostrea angulata was introduced into the North East (NE) Atlantic from Asia. The analysis of the nucleotide sequence of a highly polymorphic non-coding mitochondrial region (major noncoding region - MNR) of C. angulata samples collected in Europe (Portugal), Africa (Morocco) and Asia (Shantou and Taiwan) provided new insight into the introduction of this species into the NE Atlantic. Sixty haplotypes and a nucleotide diversity of 0.0077 were observed in 130 analyzed sequences. Higher nucleotide diversity levels were observed in NE Atlantic sites than in Asian sites and significant genetic differentiation was found between the two. Our results suggest that C. angulata might have been introduced to the... |
| Tipo: Text |
Palavras-chave: Crassostrea angulata; Phylogeography; Genetic signature; Biological invasions. |
| Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00371/48200/48316.pdf |
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| Leitao, Alexandra; Boudry, Pierre; Labat, Jean-philippe; Thiriot-quievreux, Catherine. |
| Chromosomes of six cupped oyster species were studied using karyometric analysis alter conventional Giemsa staining, and silver staining, Karyotypes of Crassotrea angulata (nine metacentric and one submetacentric chromosome pairs), C. sikamea (nine metacentric and one submetacentric chromosome pairs), C. virginica (eight metacentric and two submetacentric chromosome pairs), C, ariakensis (eight metacentric and two submetacentric chromosome pairs), C, gasar (six metacentric and four submetacentric chromosome pairs), and Saccostrea commercialis (eight metacentric and two submetacentric chromosome pairs) are distinguishable by the number and position of the submetacentric chromosome pair and by the location of nucleolus organizer regions, Comparative... |
| Tipo: Text |
Palavras-chave: Bivalvia; Cytotaxonomy; Karyotype; Chromosome; Cupped oyster. |
| Ano: 1999 |
URL: http://archimer.ifremer.fr/doc/1999/publication-2737.pdf |
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| Boudry, Pierre; Heurtebise, Serge; Lapegue, Sylvie; Lam, Katherine; Mccombie, Helen; Leitao, Alexandra; Gerard, Andre. |
| L'étude de la variabilité génétique de l'huître creuse Crassostrea gigas est un point essentiel dans la mise en place de programmes de gestion des ressources génétiques et de sélection chez cette espèce. C. gigas, originaire du Japon, a été introduite dans de nombreuses régions du monde et représente aujourd'hui plus de 95 'ro de la production mondiale d'huîtres. Introduite en France au début des années 1970 pour remplacer l'huître portugaise Crassostrea angulata, c'est aujourd'hui une ressource de première importance pour notre région. Malgré la maîtrise du cycle de reproduction de l'espèce et son importance commerciale, elle n'a pas été génétiquement améliorée et on peut donc considérer les stocks comme « sauvages» ou « non domestiqués ». De plus, la... |
| Tipo: Text |
Palavras-chave: Génétique; Huîtres creuses; Crassostrea gigas; Crassostrea gasar; Variabilité génétique. |
| Ano: 2002 |
URL: http://archimer.ifremer.fr/doc/00199/31008/29411.pdf |
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| Bouilly, Karine; Leitao, Alexandra; Mccombie, Helen; Miramand, Pierre; Lapegue, Sylvie. |
| Aneuploidy is the alteration of the normal diploid chromosome number. In the Pacifie oyster, Crassastrea gigas, hypodiploid cells have regularly been reported as have a negative correlation between this phenomenon and growth and evidence for a genetic basis. We previously demonstrated a positive relationship between a pollutant, atrazine, and aneuploidy in Crassastrea gigas adults and juveniles. To evaluate the persistence of this impact, the present study focused on a sample of the same juveniles previously exposed to different atrazine treatments (0.0 1 mg/l which represents a peak value found in a polluted environment and 0.1 mg/l) for three and a half months. Then, we evaluated them for aneuploidy after another two and a half months in non polluted... |
| Tipo: Text |
Palavras-chave: Cadmium; Atrazine; Pollutant; Pacific oyster; Aneuploidy. |
| Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/2003/acte-2852.pdf |
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| De Sousa, Joana Teixeira; Milan, Massimo; Pauletto, Marianna; Bargelloni, Luca; Joaquim, Sandra; Matias, Domitilia; Matias, Ana Margarete; Quillien, Virgile; Leitao, Alexandra; Huvet, Arnaud. |
| A microarray-based analysis was performed with the objective of describing genomic features of oocytes and looking for potential markers of oocyte quality in the economically important European clam, Ruditapes decussatus. Oocytes of 25 females from Ria de Aveiro, Western coast of Portugal (40°42′N; 08°40′W) were selected for this study and oocyte quality was estimated by success of D-larval rate under controlled conditions, which appeared to vary from 0 to 95 %. By genome-wide expression profiling with a DNA microarray, 526 probes appeared differentially expressed between two groups representing the largest and smallest value of D larval rates, named good (represented by a mean D-larval yield of 57 ± 22%) and poor (9 ± 5%) quality oocytes. Enrichment... |
| Tipo: Text |
Palavras-chave: Ruditapes decussatus; Oocyte; Developmental success; Gene expression; Marine bivalve; Transcriptomics. |
| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00260/37147/35676.pdf |
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| Leitao, Alexandra; Chaves, Raquel; Santos, Sara; Boudry, Pierre; Guedes Pinto, Henrique; Thiriot Quievreux, Catherine. |
| Chromosome preparations of the Olympia oyster Ostrea conchaphila Carpenter were studied using conventional Giemsa, silver staining, and C-banding techniques. The karyotype consists of six metacentric (1, 2, 4, 6, 8, and 10) and four submetacentric (3, 5, 7, 9) chromosome pairs. The silver-stained nucleolus organizer regions (Ag-NORs) were terminally located on the short arms of the submetacentric pair 5 (56% of cases) and on the long arms of submetacentric pair 7 (6% of cases). Constitutive heterochromatin was observed as telomeric C-bands on the short arm of the NOR-bearing chromosome pair 5 and as centromeric blocks of several chromosome pairs. Comparative analysis of patterns of karyotype, Ag-NORs, and C-bands of this species and of five other flat... |
| Tipo: Text |
Palavras-chave: Ostreinae; Cytotaxonomy; Cytogenetics; Ostrea conchaphila. |
| Ano: 2002 |
URL: https://archimer.ifremer.fr/doc/2002/publication-2792.pdf |
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| Lapegue, Sylvie; Mccombie, Helen; Leitao, Alexandra; Bouilly, Karine; Sabatier, Sebastien; Heurtebise, Serge; Boudry, Pierre; Thiriot, Catherine; Gerard, Andre. |
| Divers travaux menés depuis 1984 montrent qu'il existe, chez l'huître creuse Crassostrea gigas, des cellules montrant un nombre anormal de chromosomes (2n = 19, 18 ou même 17 au lieu de 2n = 20). Le niveau d'aneuploïdie est déterminé par le décompte des chromosomes à partir de suspensions cellulaires de tissu branchial. Le pourcentage de cellules aneuploïdes est toujours significativement supérieur dans les "lots de queue", c'est-à-dire les huîtres présentant des croissances plus faibles, et peut atteindre plus de 30 %. Récemment, une étude réalisée au sein du programme européen « Genephys » a démontré que plus de 50 % de la variance pour la vitesse de croissance était liée au taux d'aneuploïdie. Cependant, de nombreux points concernant ce phénomène... |
| Tipo: Text |
Palavras-chave: Génétique; Chromosomes; Anomalies; Aneuploïdie; Atrazine; Huîtres creuses; Crassostrea gigas. |
| Ano: 2002 |
URL: http://archimer.ifremer.fr/doc/00199/31013/29417.pdf |
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| Lapegue, Sylvie; Boutet, Isabelle; Leitao, Alexandra; Heurtebise, Serge; Garcia, P; Thiriot Quievreux, C; Boudry, Pierre. |
| Three species of man.-rove oysters, Crassostrea rhizophorae, C. brasiliana, and C. gasar, have been described along the Atlantic shores of South America and Africa. Because the distribution of these molluscs is of great biological and commercial interest, their taxonomy and distribution deserve further clarification. Therefore, 15 populations were sampled from both continents. Their 16S mitochondrial polymorphism was studied by sequencing and PCR-RFLP analysis. Two haplotypes were identified. Haplotype a was the only one observed in Africa, but it was also observed in South America together with haplotype b. Because C. gasar is the only mangrove oyster identified on the west coast of Africa, haplotype a was attributed to this species, which has thus been... |
| Tipo: Text |
Palavras-chave: Mangrove oyster; Crassostrea gasar; Karyotype; Phylogeography; 16S mitochondrial DNA. |
| Ano: 2002 |
URL: http://archimer.ifremer.fr/doc/2002/publication-2790.pdf |
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| Registros recuperados: 27 | |
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