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Registros recuperados: 33 | |
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Rohfritsch, Audrey; Bierne, Nicolas; Boudry, Pierre; Heurtebise, Serge; Cornette, Florence; Lapegue, Sylvie. |
Crassostrea gigas originated from the Pacific coast of Asia, but was introduced into several European countries in the early 1970s. Natural populations have now spread across the length of the western seaboard of Europe. To elucidate the demographic and selective processes at play during this rapid expansion, genome-scan analysis was performed on different populations. High diversities and low differentiation were observed overall, but significant genetic differentiation was found among newly established populations and between the newly established northern group and a nearly panmictic group composed of southern European populations and a population from Japan. Loss of genetic diversity was also seen in the north, likely caused by founder events during... |
Tipo: Text |
Palavras-chave: AFLPs; Crassostrea gigas; Genome scan; Invasive species; Microsatellites; SNPs. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00149/25977/24070.pdf |
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Sussarellu, Rossana; Huvet, Arnaud; Lelong, Christophe; Pernet, Fabrice; Quillen, Virgile; Lapegue, Sylvie; Cornette, Florence; Jensen, Lasse Fast; Bierne, Nicolas; Boudry, Pierre. |
Originating from north-eastern Asia, the Pacific oyster Crassostrea gigas has been introduced, mainly for aquaculture purpose, into a large number of countries. Although highly variable, its invasive nature has been reported in an increasing number of coastal areas, notably. Northern Europe. We set up a common garden experiment based on the comparison of progenies of Pacific oysters sampled in France, where populations settled since the introduction of the species in the 70’s, and Denmark, where established populations were observed since the beginning of 90s. Pure and hybrid progenies, resulting from crosses within and between adults sampled in both populations, were studied for their sex-ratio, condition index, transcriptomics, and biochemical parameters |
Tipo: Text |
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Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00167/27815/26008.pdf |
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Gagnaire, Pierre-alexandre; Cornette, Florence; Heurtebise, Serge; Auge, M. T.; Bierne, Nicolas; Lapegue, Sylvie. |
The cupped oysters Crassostrea angulata and Crassostrea gigas have been sequentially introduced in Europe from their native Pacific area for aquaculture purposes. Ongoing viral epidemic disease is responsible for large losses in oyster aquaculture production throughout Europe. In parallel with current efforts in developing selection programs for disease resistance, it becomes critically important to characterize genetic diversity patterns in both native and introduced areas. With the advent of next generation sequencing techniques, the power to resolve the fine-scale genetic structure at a genome-wide scale opens to new perspectives towards genetic resource management. Here, we present a genome-wide screen of genetic variation that combines SNP genotyping... |
Tipo: Text |
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Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00167/27816/26009.pdf |
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Gagnaire, Pierre-alexandre; Lamy, Jean-baptiste; Cornette, Florence; Heurtebise, Serge; Degremont, Lionel; Flahauw, Emilie; Boudry, Pierre; Bierne, Nicolas; Lapegue, Sylvie. |
The Pacific cupped oyster is genetically subdivided into two sister taxa, Crassostrea gigas and C. angulata, which are in contact in the north-western Pacific. The nature and origin of their genetic and taxonomic differentiation remains controversial due the lack of known reproductive barriers and the high degree of morphologic similarity. In particular, whether the presence of ecological and/or intrinsic isolating mechanisms contributes to species divergence is unknown. The recent co-introduction of both taxa into Europe offers a unique opportunity to test how genetic differentiation is maintained under new environmental and demographic conditions. We generated a pseudo-chromosome assembly of the Pacific oyster genome using a combination of BAC-end... |
Tipo: Text |
Palavras-chave: Cupped oysters; Genome assembly; Species divergence; Reproductive barriers; Recombination rate. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00455/56622/58337.pdf |
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Bierne, Nicolas; Boudry, Pierre; Lapegue, Sylvie; Bonhomme, Francois; Faure, M; Sauvage, Christopher; Moraga, D; Boutet, Isabelle; David, Elise; Jollivet, Didier; Tanguy, Arnaud; Faure, Baptiste; David, Patrice. |
For a long time, population geneticists have had to content themselves with analysing neutral markers to infer selection processes indirectly. The recent improvement of sequencing tools now enables them to analyse the variations of a large number of genes and therefore to spot the genes, or the amino acids, which are under the direct influence of the selection (Yang & Bielawski, 2000). In order to analyse the selection processes acting on the mutations and discriminate the different factors acting on their evolution (genetic selection or drift), it is essential to compare polymorphism data between genomes of the same species/population and divergence data between species/populations (Kimura, 1983). Recently, polymorphism data has become available for a... |
Tipo: Text |
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Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/rapport-6489.pdf |
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Bailleul, Diane; Mackenzie, Alicia; Sacchi, Olivier; Poisson, Francois; Bierne, Nicolas; Arnaud-haond, Sophie. |
The blue shark Prionace glauca, among the most common and widely studied pelagic sharks, is a top predator, exhibiting the widest distribution range. However, little is known about its population structure and spatial dynamics. With an estimated removal of 10 to 20 million individuals per year by fisheries, the species is classified as “Near Threatened” by International Union for Conservation of Nature. We lack the knowledge to forecast the long-term consequences of such a huge removal on this top predator itself and on its trophic network. The genetic analysis of more than 200 samples collected at broad scale (from Mediterranean Sea, North Atlantic and Pacific Oceans) using mtDNA and nine microsatellite markers allowed to detect signatures of genetic... |
Tipo: Text |
Palavras-chave: Blue shark; Conservation; Fisheries; Genetic panmixia; Prionace glauca; Stock. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00417/52866/53776.pdf |
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Plouviez, Sophie; Faure, Baptiste; Le Guen, Dominique; Lallier, Francois; Bierne, Nicolas; Jollivet, Didier. |
Comparative phylogeography of deep-sea hydrothermal vent species has uncovered several genetic breaks between populations inhabiting northern and southern latitudes of the East Pacific Rise. However, the geographic width and position of genetic clines are variable among species. In this report, we further characterize the position and strength of barriers to gene flow between populations of the deep-sea vent mussel Bathymodiolus thermophilus. Eight allozyme loci and DNA sequences of four nuclear genes were added to previously published sequences of the cytochrome c oxidase subunit I gene. Our data confirm the presence of two barriers to gene flow, one located at the Easter Microplate (between 21 degrees 33'S and 31 degrees S) recently described as a hybrid... |
Tipo: Text |
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Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00185/29622/28006.pdf |
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Sauvage, Christopher; Lapegue, Sylvie; Bierne, Nicolas; Boudry, Pierre. |
Summer mortalities of the Pacific cupped oyster Crassostrea gigas have been described in the literature for decades. One solution to overcome this problem would be to select animals more tolerant to summer mortalities, as this trait was shown to be highly heritable (Degrémont, 2003). The identification of markers associated to the resistance would allow to better understand this complex phenomenon and, eventually to establish markers assisted selection. Recently, two moderately dense genetic linkage maps have been established in the Pacific oyster based on microsatellites and AFLP markers (Hubert and Hedgecock, 2004; Li and Guo, 2004). In this context, the development and mapping of SNPs will increase the density of the linkage map and consequently the... |
Tipo: Text |
Palavras-chave: QTLs analyses; Summer mortaliy; Genetic; SNPs; Crassostrea gigas; Oyster. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/acte-3351.pdf |
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Rohfritsch, Audrey; Bierne, Nicolas; Boudry, Pierre; Heurtebise, Serge; Lapegue, Sylvie. |
Originating from the north eastern Asia, Crassostrea gigas has been introduced and translocated, mainly for aquaculture purpose, into several European countries (from Norway to Portugal and in the Mediterranean Sea) (1). Although highly variable, the invasiveness pattern of C. gigas has been demonstrated in several countries and therefore considered as a pest or a noxious species in those areas (2 and 3).Our project aims at identifying the characteristics of such a flourishing species: can its success be explained by chance and/or global warming only or does it exhibit a more important potential of adaptation than other species? Therefore we developed a population genomics approach, known as "genome scan". It corresponds to the study of numerous loci... |
Tipo: Text |
Palavras-chave: Invasive; AFLP; Genome scan; Crassotrea gigas; Pacific oyster. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/acte-4805.pdf |
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Pepin, Jean-francois; Benabdelmouna, Abdellah; Bierne, Nicolas; Chasselin, Leo; Degremont, Lionel; Guesdon, Stephane; Lamy, Jean-baptiste; Le Moine, Olivier; Normand, Julien; Robert, Stephane; Soletchnik, Patrick. |
Depuis 2014, des épisodes de mortalité anormale affectent les cheptels mytilicoles tant adultes que juvéniles. Dès l’année 2015, une étude spécifique cofinancée par la DPMA et réalisée par l’Ifremer a été initiée, l’action de recherche MORBLEU (Mortalité des moules Bleues). Les années 2015- 2017 ont permis de dégager des éléments de connaissance et des pistes relatifs aux facteurs biotiques et abiotiques qui semblent intervenir dans le phénomène de hausse de mortalité des moules depuis 2014. Pour l’année 2018, les actions d’observation et de suivis du milieu et des moules ont été fortement réduites et trois axes principaux ont été poursuivis : i) l’étude de la relation entre l’évolution des équilibres microbiens planctoniques et l’apparition de mortalités... |
Tipo: Text |
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Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00588/70056/67999.pdf |
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Bierne, Nicolas; Bezuart, Ivan; Vonau, Vincent; Bonhomme, François; Bedier, Edouard. |
Correlation between DNA microsatellite heterozygosity and growth rate was investigated in two hatchery-propagated stocks of the shrimp Penaeus stylirostris, which had been genetically isolated from wild founders for 17 generations, and from each other for five more generations. presumed demographic history of these populations suggested that they were maintained at small effective population sizes. and this was confirmed by significant changes in allelic frequencies between the two stocks. Despite a small sample size (n = 60) and a small number of loci screened, a significant positive correlation was detected between microsatellite tri-locus heterozygosity and growth rate in one of the two stocks (r = 0.3, P = 0.02). In the other stock (n = 48), the... |
Tipo: Text |
Palavras-chave: Penaeus stylirostris; Heterozygosity; Marker associated heterosis; Inbreeding depression; Microsatellites. |
Ano: 2000 |
URL: http://archimer.ifremer.fr/doc/2000/publication-753.pdf |
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Pepin, Jean-francois; Benabdelmouna, Abdellah; Degremont, Lionel; Guesdon, Stephane; Le Moine, Olivier; Morga, Benjamin; Bierne, Nicolas; Travers, Marie-agnes; Robert, Stephane; Soletchnik, Patrick. |
Depuis 2014, des épisodes de mortalité anormale affectent les cheptels mytilicoles tant adultes que juvéniles. Dès l’année 2015, une première année d’étude a été réalisée au travers de l’action MORBLEU (Mortalité des moules Bleues). Elle a été menée dans les Pertuis charentais et la baie de Bourgneuf. Dans ce même contexte, elle a été reconduite en 2016 afin de poursuivre l’analyse des données collectées en 2015, renouveler une campagne d’étude et d’observation in situ, formuler des hypothèses autour de facteurs favorisants ces épisodes de mortalité de moules, développer des essais permettant de tester ces hypothèses dans le futur et produire des lots de moules pour ces essais et pour caractériser le potentiel adaptatif des animaux face aux épisodes de... |
Tipo: Text |
Palavras-chave: Moules; Mytilus edulis; Facteurs environnementaux; Mortalité; Equilibre microbien; Populations; Qualité cytogénétique; Anomalies hémocytaires; Expression de gènes; Physiologie. |
Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00391/50288/50978.pdf |
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Registros recuperados: 33 | |
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