Figure 8.

Import of RCC1 into nuclei is saturable. Digitonin-permeabilized HeLa cells were incubated with RCC1(23-421)-GFP as an import substrate (0.6 μM). All reactions were done in the absence of a reticulocyte lysate (−RL) but in the presence of an energy regenerating system. Import was accomplished in the presence or absence of a 60-fold molar excess of unlabeled RCC1. Nuclei were visualized with DAPI (top left panels). Where indicated, GST-importin-β(45-462) (6 μM) was added; a reaction incubated on ice is also shown. Bar, 10 μm.