UPF1 shuttles between nucleus and cytoplasm independently of its RNA-binding and ATPase activities

UPF1 shuttles between the nucleus and the cytoplasm independently of its RNA-binding and ATPase activities. UPF1-GFP (WT, DE, NKR, and DE.NKR variants) were transiently expressed in HeLa cells, and GFP signal was monitored by confocal fluorescence microscopy. GFP signal (green channel) is shown in the ethanol-treated control condition and upon treatment with leptomycin B (LMB) (50 nM, 4.5 h). The scale bars in the pictures in the upper row correspond to 20 µm. The lower row shows a twofold magnification of the indicated fields.