Figure 4

Competition of influenza vRNP nuclear import with peptides against NP NLSs. Peptides carrying the NLSs of influenza NP compete for nuclear import of influenza vRNPs. (A) Fluorescein-labeled influenza vRNPs were assayed in digitonin-permeabilized HeLa cells in the presence of cytosol, an energy-regenerating system, and the absence or presence of different peptides. Cells were visualized by confocal microscopy, and representative images of three independent experiments are shown. (B) Bar diagram of the ratio of nuclear-to-cytoplasmic fluorescence for the experimental conditions shown in A. Each bar graph shows the mean value and standard error from 100–110 individual cells.