Quantification of S100A11 translocation in stress stimulated cells. The translocation of GFP-S100A11 in U-2 OS cells which were treated with BLM for 30 min to induce DNA double strand breaks (DSB) or in control cells was quantified by measurement of the average GFP-S100A11 fluorescence intensity in different areas within the cytoplasm as well as in the nucleus using MetaMorph analysis software as described in Materials and Methods. (A) The fluorescence intensity of GFP-S100A11 in five cytoplasmic areas (2 μm diameter each; stained in red, light green, violet, green and pink, respectively) localized at the nuclear membrane to cellular periphery in four different directions based on the nuclear membrane as well as of three areas (5 μm diameter each; stained in blue) randomly selected in the nucleus was measured radially. (B) Quantification of the GFP-S100A11 fluorescence signal in the cytoplasmatic areas and in nuclear areas of BLM-treated U-2 OS cells (n = 20) (grey column) or in control cells (n = 20) (white column). Data are displayed as mean values (±SD). Translocation of GFP-S100A11 in DNA damaged cells was significant between all examined areas.