Fig 4.

Detection of NFLAG-NP in virus-infected cells. (A) MDCK cells were infected with virions containing the recombinant NP vRNA. After a 7-h incubation, the FLAG epitope was detected by immunostaining with an anti-FLAG antibody. (B) Infection units (IUs), which represent the number of virions that can initiate infection and express vial proteins, were determined by detecting the number of cells that expressed NFLAG-NP. The values are means ± the standard deviations from three independent experiments. Statistical analysis was performed using the paired Student t test.