Image-Based Modeling Reveals Dynamic Redistribution of DNA Damage into Nuclear Sub-Domains
Figure 9
Increased Co-Localization of DNA Damage Markers Rapidly after Exposure to Radiation
(A) is an analysis summary of γH2AX and ATMp co-localization with 53BP1 done in 3-D. Two RIFs are considered co-localized if the distance between their centers is less than or equal to 0.48 μm. As described in Materials and Methods, RIF centers are determined as the brightest pixel within each spot. The γH2AX co-localization is illustrated in (B) with representative images of different time points and different type of radiations. γH2AX and 53BP1 foci locations are shown as green disks and red circles, respectively. Co-localized centers are circled by a yellow contour on the image, and the amount of γH2AX co-localization is reported for each image. Both exposure to γ-rays (Cs) and 1 GeV/amu Fe are illustrated for the two different time periods considered after exposure to radiation (1–4 min and 5–10 min). Averages for Cs are based on two independent experiments, whereas averages for Fe are based on four independent experiments. A t-test was performed, and a p-value of 0.01 was computed between the first and second time period considered for γH2AX (statistical significance noted on the graph as *).