Manioc : Portail | resultats 1 - 17 pour la recherche: Andersen, Tom

Avec les orpailleurs de Guyane
Auteur(s) : Quris, Bernard
Année de publication :

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Seasonal diversity and dynamics of haptophytes in the Skagerrak, Norway, explored by high-throughput sequencing
Auteur(s) : Egge, Elianne Sirnaes Johannessen, Torill Vik Andersen, Tom Eikrem, Wenche Bittner, Lucie Larsen, Aud Sandaa, Ruth-Anne Edvardsen, Bente
Auteurs secondaires : Analyse des Données à Haut Débit en Génomique (ADHDG) ; Systématique, adaptation, évolution (SAE) ; Université Pierre et Marie Curie - Paris 6 (UPMC) - Centre National de la Recherche Scientifique (CNRS) - Université Pierre et Marie Curie - Paris 6 (UPMC) - Centre National de la Recherche Scientifique (CNRS) - Evolution Paris Seine ; Université Nice Sophia Antipolis (UNS) ; Université Côte d'Azur (UCA) - Université Côte d'Azur (UCA) - Centre National de la Recherche Scientifique (CNRS) - Université des Antilles et de la Guyane (UAG) - Université Pierre et Marie Curie - Paris 6 (UPMC) - Université Nice Sophia Antipolis (UNS) ; Université Côte d'Azur (UCA) - Université Côte d'Azur (UCA) - Université des Antilles et de la Guyane (UAG) Research Council of Norway [190307 HAPTODIV] ASSEMBLE FP7 grant [227799] EU project BioMarKs (ERA-net Biodiversa, EU) [2008-6530] MINOS - EU-ERC [250254]

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
Microalgae in the division Haptophyta play key roles in the marine ecosystem and in global biogeochemical processes. Despite their ecological importance, knowledge on seasonal dynamics, community composition and abundance at the species level is limited due to their small cell size and few morphological features visible under the light microscope. Here, we present unique data on haptophyte seasonal diversity and dynamics from two annual cycles, with the taxonomic resolution and sampling depth obtained with high-throughput sequencing. From outer Oslofjorden, S Norway, nano- and picoplanktonic samples were collected monthly for 2years, and the haptophytes targeted by amplification of RNA/cDNA with Haptophyta-specific 18S rDNA V4 primers. We obtained 156 operational taxonomic units (OTUs), from c. 400.000 454 pyrosequencing reads, after rigorous bioinformatic filtering and clustering at 99.5%. Most OTUs represented uncultured and/or not yet 18S rDNA-sequenced species. Haptophyte OTU richness and community composition exhibited high temporal variation and significant yearly periodicity. Richness was highest in September-October (autumn) and lowest in April-May (spring). Some taxa were detected all year, such as Chrysochromulina simplex, Emiliania huxleyi and Phaeocystis cordata, whereas most calcifying coccolithophores only appeared from summer to early winter. We also revealed the seasonal dynamics of OTUs representing putative novel classes (clades HAP-3-5) or orders (clades D, E, F). Season, light and temperature accounted for 29% of the variation in OTU composition. Residual variation may be related to biotic factors, such as competition and viral infection. This study provides new, in-depth knowledge on seasonal diversity and dynamics of haptophytes in North Atlantic coastal waters. See also the Perspective by Massana
ISSN: 0962-1083

hal-01545321
https://hal.archives-ouvertes.fr/hal-01545321
DOI : 10.1111/mec.13160

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