Molecular characterization and expression analysis of two type I interferons from Asian Seabass (Lates calcarifer) during nervous necrosis virus infection

The intensification of Asian Seabass aquaculture has led to the emergence of viral diseases such as viral nervous necrosis (VNN), which cause massive mortalities and enormous economic losses in the region. Currently, there are no effective prophylactic or therapeutic measures against the etiological agent of the disease-the nervous necrosis virus (NNV). Though the innate immune response against viruses in teleosts is mainly mediated by type I interferons, no interferons have yet been identified in Lates calcarifer. We report the cloning and characterization of two 2-cysteine-containing type I IFNs from Lates. Based on phylogenetic analysis and protein sequence, these belong to subgroups d and h of type I IFNs with two cysteines. We found constitutive expression of these LcIFN mRNAs in the brain, blood, fin, gill, heart, intestine, head kidney, spleen and muscle. The expression was significantly induced upon poly(I:C) injection in the head kidney, heart and gill. Significant upregulation of LcIFN expression was also observed in Lates head kidney, spleen and heart following in vivo infection with RGNNV. These two Lates IFNs appear to be important antiviral molecules in the host innate immune response against betanodavirus and other emerging viruses threatening Lates aquaculture.

Automated summary

The intensification of Asian Seabass aquaculture has led to the emergence of viral diseases such as viral nervous necrosis (VNN), which cause massive mortalities and enormous economic losses in the region. Currently, there are no effective prophylactic or therapeutic measures against the etiological agent of the disease-the nervous necrosis virus (NNV). We report the cloning and characterization of two 2-cysteine-containing type I IFNs from Lates calcarifer, which play an important role in the host innate immune response against betanodavirus and other emerging viruses threatening Lates aquaculture.