Unmethylated GFP-RAB7 and GFP-RAB8 are mislocalized from endomembranes to the cytosol. (A) U2OS cells were treated for 3 d with either NT or ICMT siRNA before transfection with either GFP-RAB7 or GFP-RAB8. The cells were imaged live by confocal microscope the following day. Bars: (main images) 10 µm; (insets) 2.5 µm. Arrowheads show prominent nuclear envelope/ER decoration. (B) U2OS cells with or without genomic disruption of ICMT by CRISPR/Cas9 were transfected with constructs for the indicated fluorescent proteins and then imaged 1 d later by confocal microscopy. Bar, 10 µm. Below the representative images are graphs showing the means ± SEM. Pearson’s correlation coefficient for the colocalization of the GFP-tagged protein with mCherry-ER3. Data are from two independent experiments. n ≥ 16. *, P < 0.05; **, P < 0.01 (two-sided t test).