Fig. 2.

Ku70/80 interaction with DSBs in vivo. (A) Example of EGFP-Ku80 accumulation after laser irradiation of a disk inside the nucleus of XR-V15B cells expressing EGFP-Ku80. (B) Accumulation curve of EGFP-Ku80 on laser-induced DNA damage. For every cell, the pre-damage fluorescence level was set to 0 and the maximum was set to 1. The average and twice the SEM of a total of at least 10 cells is depicted in the graph. (Inset) Ku accumulation between 0 and 8 min in untreated cells shown in more detail. Filled circles represent untreated cells, and open triangles represent cells treated with Wortmannin. (C) Example of FRAP on a local EGFP-Ku80 accumulation. (D) FRAP on local damage curve for EGFP-Ku80. The data were normalized to the prebleach fluorescence level. The average and twice the SEM of 10 independent FRAP curves are depicted in the graph. The open circles represent the FRAP curve, and the filled circles show loss of fluorescence due to ongoing repair (from B). (Scale bars: 5 μm.)