BTRC and infection: To test whether β-TrCP affects IAV replication in mammalian cells, HEK-293T cells were either transfected with small interfering RNA (siRNA) (siβ-TrCP-1# and siβ-TrCP-2#,10 nM) or pFlag-β-TrCP(0,1 and 2μg) eukaryotic plasmid for 48 h followed by infection of these cells with PR8 at 1 m.o.i for an additional 12 h, respectively.