Contribution of Viral Genomic Diversity to Oyster Susceptibility in the Pacific Oyster Mortality Syndrome

• Published in: Frontiers in Microbiology
• Main Authors: Delmotte, Jean, Chaparro, Cristian, Galinier, Richard, de Lorgeril, Julien, Petton, Bruno, Stenger, Pierre-Louis, Vidal-Dupiol, Jeremie, Destoumieux-Garzón, Delphine, Gueguen, Yannick, Montagnani, Caroline, Escoubas, Jean-Michel, Mitta, Guillaume
• Other Authors: Interactions Hôtes-Pathogènes-Environnements (IHPE), Université de Perpignan Via Domitia (UPVD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM), 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 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)-Centre National de la Recherche Scientifique (CNRS), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), ANR-14-CE19-0023,DECIPHER,Déchiffrage des maladies multifactorielles: cas des mortalités de l'huître(2014), ANR-11-IDEX-0002,UNITI,Université Fédérale de Toulouse(2011)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2020
• Subjects: herpesvirus diversity; genotype-genotype interactions; oyster genetic background; viral populations; Crassostrea gigas; acl; [SDV.MP.VIR]Life Sciences [q-bio]/Microbiology and Parasitology/Virology; [SDV.BA.MVSA]Life Sciences [q-bio]/Animal biology/Veterinary medicine and animal Health; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; Pacific; Pacific oyster
• Online Access: https://hal.science/hal-02915023; https://hal.science/hal-02915023/document; https://hal.science/hal-02915023/file/Delmotte-2020-FrontMicrobiol-Contribution.pdf; https://doi.org/10.3389/fmicb.2020.01579

International audience Juvenile Pacific oysters (Crassostrea gigas) are subjected to recurrent episodes of mass mortalities that constitute a threat for the oyster industry. This mortality syndrome named "Pacific Oyster Mortality Syndrome" (POMS) is a polymicrobial disease whose pathogenesis is initiated by a primary infection by a variant of an Ostreid herpes virus named OsHV-1 µVar. The characterization of the OsHV-1 genome during different disease outbreaks occurring in different geographic areas has revealed the existence of a genomic diversity for OsHV-1 µVar. However, the biological significance of this diversity is still poorly understood. To go further in understanding the consequences of OsHV-1 diversity on POMS, we challenged five biparental families of oysters to two different infectious environments on the French coasts (Atlantic and Mediterranean). We observed that the susceptibility to POMS can be different among families within the same environment but also for the same family between the two environments. Viral diversity analysis revealed that Atlantic and Mediterranean POMS are caused by two distinct viral populations. Moreover, we observed that different oyster families are infected by distinct viral populations within a same infectious environment. Altogether these results suggest that the co-evolutionary processes at play between OsHV-1 µVar and oyster populations have selected a viral diversity that could facilitate the infection process and the transmission in oyster populations. These new data must be taken into account in the development of novel selective breeding programs better adapted to the oyster culture environment.