FIGURE 2.

ATM is required for nuclear accumulation of DYRK2 in response to genotoxic stress. A, U2OS cells were co-transfected with GFP-DYRK2 and scramble siRNA or ATM-specific siRNA (20) and then treated with etoposide for 24 h. Cells were stained with anti-GFP (left). The nuclei were stained with DAPI (left). Cell lysates were subjected to immunoblot analysis (IB) with anti-ATM (right, upper panel) or anti-tubulin (right, lower panel). B, U2OS cells were transfected as in A. The localization of DYRK2 was scored according to whether it was higher in the nucleus (open bars), evenly distributed between the nucleus and the cytoplasm (dotted bars), or higher in the cytoplasm (closed bars). Results are the mean ± S.D. of values obtained from 5 fields of 30–100 cells in each of three independent experiments. Statistical analysis was performed with Student's t test. The single asterisk and n.s. indicate p < 0.05 and not significant, respectively. C, GM 5849/pEBS7 (vector) or GM 5849/pEBS7-YZ5 (ATM) cells were transfected with GFP-DYRK2 and left untreated or treated with 10 μm etoposide for 24 h. Cells were stained with anti-GFP. The nuclei were stained with DAPI.