title: Antiviral and metabolic gene expression responses to viral infection in Atlantic salmon (Salmo salar).
abstract: Salmonid alphavirus (SAV), the aetiological agent of pancreas disease, is recognized as a serious pathogen of farmed Atlantic salmon. This disease results in loss of weight followed by poor growth of surviving fish, as such it is viewed as a wasting disease. SAV and other chronic disease causing viruses affect the heart and skeletal muscle tissues, at present the mechanisms by which pathology occurs is unknown. The relationship between antiviral activity and other physiological parameters especially in skeletal muscle are currently not examined in depth in fish. An experimental SAV (isotype 3) infection was carried out using a cohabitation approach, from which samples were collected at 0, 4, 8 & 12 week post challenge. Maximum viral load in the muscle tissue was 4 weeks post infection which was reduced at 8 weeks and undetectable by 12 weeks. Histopathology score peaked at 4 weeks post infection in pancreas and heart whereas there was maximum damage in skeletal muscle at 8 weeks. The peak expression of antiviral immune genes coincided with the viral load. Several genes involved in protein degradation were increased following infection including atrogin-1 and cathepsin D, at 4 weeks post challenge suggesting reallocation of amino acid reserves. Taken together, these observations increase our understanding of salmon poor growth during viral infection, and will serve as a basis to develop strategies to manage this viral wasting disease.
authors.affiliation: Institute of Biological and Environmental Sciences, University of Aberdeen, Tillydrone Avenue, Aberdeen AB24 2TZ, UK.
authors.forename: Zeynab
authors.initials: Z
authors.lastname: Heidari
authors.affiliation: BioMar Ltd, Grangemouth Docks, Grangemouth FK3 8UL, UK.
authors.forename: John
authors.initials: J
authors.lastname: Tinsley
authors.affiliation: BioMar Ltd, Grangemouth Docks, Grangemouth FK3 8UL, UK.
authors.forename: Ralph
authors.initials: R
authors.lastname: Bickerdike
authors.affiliation: Fish Vet Group, 22 Carsegate Road, Inverness IV3 8EX, UK.
authors.forename: Marian F
authors.initials: MF
authors.lastname: McLoughlin
authors.affiliation: Institute of Biological and Environmental Sciences, University of Aberdeen, Tillydrone Avenue, Aberdeen AB24 2TZ, UK.
authors.forename: Jun
authors.initials: J
authors.lastname: Zou
authors.affiliation: Institute of Biological and Environmental Sciences, University of Aberdeen, Tillydrone Avenue, Aberdeen AB24 2TZ, UK. Electronic address: Sam.martin@abdn.ac.uk.
authors.forename: Samuel A M
authors.initials: SA
authors.lastname: Martin
mesh_terms: D000524:Alphavirus / Q000502:physiology; D018354:Alphavirus Infections / Q000235:genetics / Q000378:metabolism / Q000662:veterinary* / Q000821:virology; D000818:Animals; D000998:Antiviral Agents / Q000378:metabolism*; D004734:Energy Metabolism; D005393:Fish Diseases / Q000235:genetics* / Q000378:metabolism / Q000821:virology; D029941:Fish Proteins / Q000235:genetics* / Q000378:metabolism; D005786:Gene Expression Regulation; D018482:Muscle, Skeletal / Q000378:metabolism* / Q000821:virology; D059748:Proteolysis; D060888:Real-Time Polymerase Chain Reaction / Q000662:veterinary; D020317:Salmo salar; D019562:Viral Load / Q000662:veterinary
chemical_list: D000998:Antiviral Agents; D029941:Fish Proteins
keywords: Atlantic salmon; Atrogin-1; Gene expression; SAV; Salmonid alphavirus