Fig. 4. The N-terminal region of Xp54 fused to GFP behaves like a shuttling protein in transfected culture cells. (A) Fluorescence images of Xenopus XTC2 cells, mouse AC29 cells and canine MDCK cells expressing NT-GFP and MDCK cells expressing GFP. (B) Treatment of transfected HeLa cells with 5 nM LMB for four hours prior to fixation results in nuclear accumulation of NT-GFP. Fluorescence (FL) and confocal (CF) images are shown. Cells were treated with 5 µg/ml actinomycin D (AMD) two hours before treatment with LMB. (C) Cold, but not treatment with cycloheximide (CHX), inhibits LMB-dependent nuclear accumulation of NT-GFP in transfected HeLa cells. The fluorescence images are of cells cooled to 6°C after addition of LMB; cells treated with 20 µg/ml CHX for two hours prior to addition of LMB and maintained at 32°C and cells treated with CHX and cooled to 6°C.
