FIG. 4.
Nuclear shuttling of GFP-IκBα chimeric proteins in transfected HeLa cells. HeLa cells transfected with expression vectors for the indicated GFP-IκBα fusion proteins were left untreated or were treated with leptomycin B for 1 h. The cellular localization of the fusion proteins was detected by indirect immunofluorescence with a chicken antibody raised against GFP. More than 200 cells were examined for each fusion protein (see Table 1 for quantitation), and representative cells are shown.