A serine-rich cluster is present in the duck sequence near Serine 496 and contains the motif HLGLS, which resembles the consensus pLxIS motif containing (human) Serine 442 that becomes phosphorylated by IKKβ and TBK1 upon viral infection, leading to recruitment and phosphorylation of IRF3 [49]. This evidence concerns the gene IKBKB and viral infectious disease.