Integrative study of physiological changes associated with bacterial infection in pacific oyster larvae.

• Published in: PLoS ONE
• Main Authors: Genard, Bertrand, Miner, Philippe, Nicolas, Jean-Louis, Moraga, Dario, Boudry, Pierre, Pernet, Fabrice, Tremblay, Réjean
• Other Authors: Institut des Sciences de la MER de Rimouski (ISMER), Université du Québec à Rimouski (UQAR), Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Environnement Ressources (LER-LR), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Institut des Sciences de la Mer
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2013
• Subjects: [SDE]Environmental Sciences; Pacific; Crassostrea gigas; Pacific oyster
• Online Access: https://hal.univ-brest.fr/hal-00833831; https://hal.univ-brest.fr/hal-00833831/document; https://hal.univ-brest.fr/hal-00833831/file/PLOS-Genard.pdf; https://doi.org/10.1371/journal.pone.0064534

International audience BACKGROUND: Bacterial infections are common in bivalve larvae and can lead to significant mortality, notably in hatcheries. Numerous studies have identified the pathogenic bacteria involved in such mortalities, but physiological changes associated with pathogen exposure at larval stage are still poorly understood. In the present study, we used an integrative approach including physiological, enzymatic, biochemical, and molecular analyses to investigate changes in energy metabolism, lipid remodelling, cellular stress, and immune status of Crassostrea gigas larvae subjected to experimental infection with the pathogenic bacteria Vibrio coralliilyticus. FINDINGS: Our results showed that V. coralliilyticus exposure induced (1) limited but significant increase of larvae mortality compared with controls, (2) declined feeding activity, which resulted in energy status changes (i.e. reserve consumption, β-oxidation, decline of metabolic rate), (3) fatty acid remodeling of polar lipids (changes in phosphatidylinositol and lysophosphatidylcholine composition', non-methylene-interrupted fatty acids accumulation, lower content of major C20 polyunsaturated fatty acids as well as activation of desaturases, phospholipase and lipoxygenase), (4) activation of antioxidant defenses (catalase, superoxide dismutase, peroxiredoxin) and cytoprotective processes (heat shock protein 70, pernin), and (5) activation of the immune response (non-self recognition, NF-κκ signaling pathway, haematopoiesis, eiconosoids and lysophosphatidyl acid synthesis, inhibitor of metalloproteinase and antimicrobial peptides). CONCLUSION: Overall, our results allowed us to propose an integrative view of changes induced by a bacterial infection in Pacific oyster larvae, opening new perspectives on the response of marine bivalve larvae to infections.