Effect of RK424 on cytoplasmic localization of NP.

<p>(A) HeLa cells were infected with A/WSN/1933 (H1N1) virus at an MOI of 10 in the absence or presence of 0.5 and 2 μM of RK424 for 6 h. Subcellular localization of NP was observed by indirect immunofluorescence staining with anti-NP MAb under a confocal laser scanning microscope. Three independent experiments were performed and one representative result is shown. (B) HeLa cells were transfected for 48 h with NP/pCAGGS plasmid in the absence or presence of RK424 (0.5μM and 2 μM). The subcellular localization of NP was observed as described for virus-infected cells. Three independent experiments were performed and one representative result is shown. (C) The percentage of cells showing nuclear localization (black bar) or cytoplasm localization (white bar) of NP was calculated by counting 500 cells per sample. Oseltamivir phosphate (Os) was used as a negative control. Data are expressed as the mean ± SD in each of three independent experiments.