Establishment of an Atlantic salmon kidney cell line with an inducible gene expression system.

A stable recombinant Atlantic Salmon Kidney cell line ASK for use as an inducible expression system was isolated, cloned and characterised. The cells were transfected with the pTet-Off plasmid from the Tet On/Off Clontech system, carrying a G418 resistance gene. Several G418-resistant clones were sub-cultured and characterised by qPCR and by transient transfection. The level of expression of transcriptional activator (tTA) was measured by qPCR in a number of isolated clones. Transient transfection with a pTRE2-hyg-LUC plasmid was used to evaluate the inducibility of these clones. Two clones were chosen for their compromise between cell growth and inducibility. This genetically engineered cell line is a valuable tool for the fish research community especially in research areas investigating the biological function of viral proteins.