Fig. 1.

Schematic diagram of chimeric cH9/H17 and cN2/N10, growth kenetics, polymerase activity, IFN-β antagonism assay. A: green bars represent packaging signal sequence from HA and NA genes of the A/little yellow-shouldered bat/Guatemala/164/2009 (H17N10); gray bars represent HA or NA coding regions from HA and NA genes of A/mink/China/02/2014(H9N2); cH9/H18 and cN2/N11 genes were generated similarly; B: growth dynamics of cH9cN2/H17, cH9cN2/H18, and H9N2-wt viruses on CEF cells. Monolayer of CEF cells were infected with 0.01 MOI of each virus, and samples were collected at indicated time points. The virus titers were measured in MDCK cells. C: polymerase activity of vRNPs of H17N10, H18N11, and H9N2. D: IFN-β antagonism activity of NS1 proteins of H17N10, H18N11 and H9N2-wt. Each data point indicates the MEAN ± SEM of three independent experiments, ***P < 0.001, *P < 0.05 (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article).