Figure 4. Increased DNA damage in MEFs lacking Tgif1.

Passage 2 wild type and Tgif1 null cells were analyzed by comet assay, under denaturing conditions. The percentage of total DNA in the tail was quantified for at least 50 cells per condition. A) The percentage of DNA in the tail is plotted for each of two independent batches of wild type and Tgif1 null MEFs. Data is plotted as median, 25^th and 75^th percentiles (box) and 5^th and 95^th percentiles (whiskers). p-values determined by the Student's T test are shown. B) The data shown in A, binned into 5% blocks, are plotted to show the distribution. C) Cells were treated with 100 µM H₂O₂ for 20 minutes and analyzed by comet assay at time-points thereafter over a 160 minute time-course. Data are presented as in A, with p-values for comparisons between wild type and Tgif1 null shown where significant. D) representative images of mitotic cells with DNA bridges are shown for Tgif1 null cells. Cells analyzed for α-tubulin (green), pHH3 (red), and Hoechst (blue) are shown, together with a merged image of all three colors. Images were captured at 40×. Scale bar = 25 µM. E) Wild type and Tgif1 null MEFs were grown on a 3T3 protocol in a standard incubator (5% CO₂ in air [20% O₂]), or in a chamber with 5% CO₂ and 3% O₂. Growth is plotted as relative cumulative cell number, with the starting 300,000 cells at P2 set equal to 1.