Deletion of <i>Polh</i> does not ameliorate phenotypes caused by knockout of <i>Rev3l</i>.

<p>(A) Genotypes of mouse pups produced by breeding parental <i>Rev3l</i><sup>-/lox</sup><i>Polh</i><sup>-/</sup>—mice. (B) MEFs with the indicated genotypes were stained with DAPI, and for 53BP1 and γ-H2AX by immunofluorescence as in <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1005759#pgen.1005759.g002" target="_blank">Fig 2</a> to detect foci of DNA double-strand breaks. The quantification shows the percentage of cells with >2 53BP1 and γ-H2AX foci in <i>Rev3l</i><sup>-/lox</sup><i>Polh</i><sup>+/+</sup>, <i>Rev3l</i><sup>-/lox</sup><i>Polh</i><sup>-/-</sup>, <i>Rev3l</i><sup>-/Δ</sup><i>Polh</i><sup>+/+</sup> and <i>Rev3l</i><sup>-/Δ</sup><i>Polh</i><sup>-/-</sup> MEFs 9 days after AdCre treatment. (C) Survival of primary MEFs as in part B, 120 hr after addition of cisplatin, as measured by ATP content. For panels B& C, Data represent mean ± SEM.</p>