Fig. 6. hADAR1 and hADAR2 co-localize within the nucleolus. HeLa cells were transfected with GFP-ADAR2, incubated in the absence (A) or in the presence (B) of actinomycin D (0.07 µg ml^-1) for 1 hour and double-labeled with a monoclonal antibody against fibrillarin. The merged images show clearly that GFP-ADAR2 (green) and fibrillarin (red) do not co-localize. (C) HeLa cells were co-transfected with GFP-ADAR2 and Flis-ADAR1C-Term (Fig. 2A). Approximately 16 hours after transfection, cells were fixed, immunostained with anti-FLAG antibody (red) and analysed by confocal microscopy. GFP-ADAR2 and Flis-ADAR1 co-localize in the nucleolus of co-transfected cells, as can be seen in the merged image (yellow). Images from the same microscopic fields are shown side by side. The dashed lines indicate the contour of the HeLa cell nucleus. Bar, 10 µm.