Fig. 4
Replication stress-triggered MSI/hypermutation is associated with the induction of ARF/p53-module mutations. a Individual sequence reads obtained during exome analyses were aligned onto the Cdkn2a gene locus and visualized using the Integrative Genomics Viewer at each cellular stage. Deletion status of this gene locus was also analyzed based on numbers of sequence reads at exons 1 and 2. Chi-squared test was used for statistical analysis. b Msh2+/+ and Msh2−/− MEFs were treated as shown in the upper box. Expression of the replicative Polδ and the TLS polymerases η, κ, and ι was analyzed by western blotting. Red arrowheads indicate the signals when each polymerase was highly expressed. Graphs show means ± s.e. (n = 3 independent experiments with MEFs prepared from independent fetuses). c, d Msh2+/+ and Msh2−/− MEFs were treated according to the workflow. γH2AX foci were detected by immunofluorescence (c, n numbers are indicated in graph). Percentages of γH2AX foci colocalized with 53BP1 foci (means ± s.e.) are indicated in each image (d). Bars show means ± s.d. Scale bars, 10 μm. Two-tailed Welch’s t-test was used for statistical analysis
