Figure 6.

Nuclear accumulation of β-catenin does not require Ran in vitro. Upper panel, digitonin-permeabilized MDBK cells were incubated with a 10-μl testing solution containing 8 pmol of FLAG-β-catenin in the absence (a) or presence of 80 pmol of Ran-GDP (b) or 80 pmol of G19V Ran-GTP (c). After incubation for 30 min at 30°C, the cells were fixed, and the localization of FLAG-β-catenin was examined as in Figure 3. Lower panel, digitonin-permeabilized MDBK cells were incubated with 10 μl of testing solution containing 3 pmol GFP-importin β in the absence (a) or presence of 80 pmol of G19V Ran-GTP (b). After incubation for 20 min at 30°C, the cells were fixed, and the localization of GFP-importin β was examined by Axiophoto microscopy (Zeiss).