Figure 2.

DNA repair defect in PAXX KO mice. (a) Radiosensitivity assay performed on mature splenic T lymphocytes. For FACS analysis, doubling populations were scored in gates defined by the dilution of the CellTrace signal and the proliferative index calculated according to Roederer.²⁶ The relative proliferative indexes were plotted for each sample according to the proliferation in the absence of IR and used to define the radiosensitivity level. The experiment was repeated twice with two mice per genotype each time. (b) Phleomycin and IR sensitivity on SV40-transformed MEFs. MEFs from XRCC4, DNA-Ligase IV, and Xlf KO mice were used as radiosensitive controls. The relative growth indexes were calculated by comparing the confluence of treated cells and non-treated cells during culture with real-time Incucyte monitoring (see Materials and Methods). This experiment was repeated three times