Project leader: Professor Børre Robertsen

Type I interferons (IFN) are cytokines, which induce an antiviral state in vertebrate cells by induction of Mx and other proteins that inhibit viral replication. Viruses induce production of type I IFN in cells by double-stranded RNA intermediates produced during replication. We have cloned two genes from Atlantic salmon, which encode proteins with functional and molecular properties similar to mammalian type I IFN. The mature Atlantic salmon IFNs contain 152 amino acids (18.2 kDa). The salmon IFNs showed 45 % sequence identity with zebrafish IFN, up to 29 % identity with mammalian IFN-alfa sequences. Recombinant salmon IFN produced in Human embryonic kidney 293 cells protects salmonid cells against infectious pancreatic necrosis virus (IPNV) and induces Mx protein in the cells. The cloned salmon IFNs represent an important tool for the study of defense mechanisms of Atlantic salmon against economically important viral pathogens.

The aim of the present project is to express Atlantic salmon interferon in E. coli for the purpose of determining its 3-D structure by X-ray crystallography.