First detection of OsHV-1 in the cephalopod Octopus vulgaris. Is the octopus a dead-end for OsHV-1?
|Author(s)||Prado-Alvarez Maria1, García-Fernández Pablo1, Faury Nicole2, Azevedo Carlos3, 4, Morga Benjamin2, Gestal Camino1|
|Affiliation(s)||1 : Marine Molecular Pathobiology Group, Marine Research Institute, Spanish National Research Council, Eduardo Cabello 6, 36208 Vigo, Spain
2 : IFREMER, Laboratoire de Génétique et Pathologie des Mollusques Marins, Avenue de Mus de Loup, 17390 La Tremblade, France
3 : Interdisciplinary Center of Marine and Environmental Research, University of Porto, Rua dos Bragas 289, 4050-123 Porto, Portugal
4 : Institute of Biomedical Sciences Abel Salazar, University of Porto, Rua Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
|Source||Journal Of Invertebrate Pathology (0022-2011) (Elsevier BV), 2021-07 , Vol. 183 , P. 107553 (13p.)|
|WOS© Times Cited||5|
|Keyword(s)||Octopus vulgaris, Crassostrea gigas, OsHV-1, Gene expression, In situ hybridization|
The ostreid herpes virus (OsHV-1), associated with massive mortalities in the bivalve Crassostrea gigas, was detected for the first time in the cephalopod Octopus vulgaris. Wild adult animals from a natural breeding area in Spain showed an overall prevalence of detection of 87.5% between 2010 and 2015 suggesting an environmental source of viral material uptake. Overall positive PCR detections were significantly higher in adult animals (p = 0.031) compared to newly hatched paralarvae (62%). Prevalence in embryos reached 65%. Sequencing of positive amplicons revealed a match with the variant OsHV-1 µVar showing the genomic features that distinguish this variant in the ORF4. Gill tissues from adult animals were also processed for in situ hybridization and revealed positive labelling. Experimental exposure trials in octopus paralarvae were carried out by cohabitation with virus injected oysters and by immersion in viral suspension observing a significant decrease in paralarval survival in both experiments. An increase in the number of OsHV-1 positive animals was detected in dead paralarvae after cohabitation with virus injected oysters. No signs of viral replication were observed based on lack of viral gene expression or visualization of viral structures by transmission electron microscopy. The octopus response against OsHV-1 was evaluated by gene expression of previously reported transcripts involved in immune response in C. gigas suggesting that immune defences in octopus are also activated after exposure to OsHV-1.