Molecular cloning of IKKβ from the mandarin fish Siniperca chuatsi and its up-regulation in cells by ISKNV infection

The IκB kinase β (IKKβ) plays crucial roles in regulating activation of nuclear factor-kappa B (NF-κB) in response to proinflammatory factors and microbial and viral infections. Here, we report the cloning of an IKKβ cDNA (named SicIKKβ) from the mandarin fish Siniperca chuatsi. The full-length cDNA is 4052 bp and contains an ORF that encodes a predicted protein of 743-amino acid residues. The deduced amino acid sequence of SicIKKβ has the same domain organization as human IKKβ, which consists of a serine/threonine kinase domain, a leucine zipper motif and a putative helix-loop-helix motif. Quantitative RT-PCR showed that SicIKKβ was ubiquitously expressed in tissues of mandarin fish, and its expression in mandarin fish fry (MFF-1) cells was up-regulated during the course of ISKNV infection.