ATM or ATR inhibition does not affect incorporation of nucleotides into SV40 DNA.

<p>(A) Southern blot of DNA extracted from SV40-infected BSC40 cells treated with DMSO, ATRi, or ATMi from 40 to 48 hpi and labeled with 20 µM EdU for 30 minutes prior to DNA extraction. Left Panel: phosphorimager scan of Southern blot probed for mitochondrial or SV40 DNA. Right Panel: same Southern blot as in left panel but probed for EdU with an anti-BrdU antibody. (B, C) Western blots of cells lysates from SV40-infected BSC40 cells treated with DMSO, ATRi, or ATMi during the final 8 h of a 48 h SV40 infection. (D) Immunofluorescence microscopy of the indicated factors from SV40- or mock-infected BSC40 cells treated with DMSO, ATRi, or ATMi during the final 8 h of a 48 h SV40 infection. Prior to fixation at 48 hpi, cells were pulsed with 20 µM EdU for 5 minutes and non-chromatin bound proteins were extracted from cells. The fluorescence intensity along the line shown in the merged image is graphed in the right panel. Scale bars represent 10 µm. (E, F) Fluorescence intensity signals of Rad51 (E) or EdU (F) at a minimum of 100 SV40 DNA replication centers from micrographs as in (D). Dashed and solid lines within boxes represent the average and median, respectively. Boxes contain the 25th–75th quartiles of intensities, whereas whiskers show minimum and maximum intensities.