The interplay between infectious pancreatic necrosis virus (IPNV) and the IFN system: IFN signaling is inhibited by IPNV infection.
Infectious pancreatic necrosis virus (IPNV) is a major pathogen in the aquaculture industry worldwide. Factors contributing to IPNV pathogenicity are yet poorly understood. Indications of IPNV being able to evade or counteract innate host defense come from its lack of ability to induce strong type I interferon (IFN) responses in cell culture. We show here that addition of salmon rIFN-alpha1 to cells prior to IPNV infection halts the viral protein synthesis and prevents processing of pVP2 into mature VP2. Furthermore, compared to pre-treatment with IFN-alpha1 the antiviral state in cells infected with IPNV prior to IFN-treatment, was antagonized by IPNV, as detected by higher viral titers, faster viral protein synthesis and also by reduced Mx expression. The longer headstart the virus gets, the more prominent is the weakening of IFN signaling. IPNV VP4 and VP5 inhibit IFN-induced expression from the Mx promoter, indicating that these proteins contribute to the antagonistic effect.
Skjesol
Astrid
A
Department of Marine Biotechnology, Norwegian College of Fishery Sciences, University of Tromsø, Breivika, N- 9037 Tromsø, Norway.
Aamo
Toril
T
Hegseth
Marit Nøst
MN
Robertsen
Børre
B
Jørgensen
Jorunn B
JB
D000818:Animals; D000998:Antiviral Agents / Q000494:pharmacology; D018175:Birnaviridae Infections / Q000188:drug therapy / Q000378:metabolism / Q000662:veterinary* / Q000821:virology; D002460:Cell Line; D005393:Fish Diseases / Q000188:drug therapy* / Q000378:metabolism / Q000821:virology*; D019204:GTP-Binding Proteins / Q000096:biosynthesis / Q000235:genetics; D005786:Gene Expression Regulation; D054884:Host-Pathogen Interactions; D018061:Infectious pancreatic necrosis virus / Q000187:drug effects* / Q000472:pathogenicity / Q000502:physiology; D016898:Interferon-alpha / Q000494:pharmacology*; D064547:Myxovirus Resistance Proteins; D012474:Salmon; D012697:Serine Endopeptidases / Q000378:metabolism; D015398:Signal Transduction; D017361:Viral Nonstructural Proteins / Q000378:metabolism; D015678:Viral Structural Proteins / Q000378:metabolism; D014774:Virulence; D014779:Virus Replication / Q000187:drug effects
D000998:Antiviral Agents; D016898:Interferon-alpha; D064547:Myxovirus Resistance Proteins; C509831:VP2 protein, infectious pancreatic necrosis virus; C518635:VP5 protein, infectious bursal disease virus; D017361:Viral Nonstructural Proteins; D015678:Viral Structural Proteins; D012697:Serine Endopeptidases; C414992:VP4 protease, birnavirus; D019204:GTP-Binding Proteins