Abstract 2384: Time-lapse imaging of response to DNA damage occuring during mitosis

Abstract

Abstract The DNA damage response protein 53BP1 forming foci when double-stranded breaks occur in DNA. In this study, the response to DNA damage during mitosis was visualized using fluorescent protein-based real-time imaging of 53BP1 linked to GFP (GFP-53BP1) focus formation by the fusion protein in the MiaPaCa2 Tet-On Advanced cell line. The MiaPaCa2Tet-On GFP-53BP1 cells were cultured in 35 mm dishes for 48 h. 53BP1 foci were observed every 30 minutes with the FluoView FV1000 confocal laser microscope (Olympus Corp., Tokyo, Japan). The increased expression of GFP-53BP1 was observed during mitosis in MiaPaCa2Tet-On GFP-53BP1 cells without any treatment Mitotic changes were observed 1.09 ± 0.10 times in each cell during over 24 h. Apoptotic changes were observed in 7.3 ± 3.3% of the cells during the 24 h. During the time-lapse imaging, focus formation of GFP-53BP1 was observed in 11.4 ± 2.1% of the mitotic cells during over 24 h. Non-mitotic cells did not have an increase in GFP-53BP1 focus formation. This study indicates that DNA strand breaks occur during mitosis and can be repaired, at least to some extent. Citation Format: Shinji Miwa, Shuya Yano, Mako Yamamoto, Yukihiko Hiroshima, Fuminari Uehara, Yasunori Matsumoto, Hiroaki Kimura, Katsuhiro Hayashi, Elena V. Efimova, Hiroyuki Tsuchiya, Robert M. Hoffman. Time-lapse imaging of response to DNA damage occuring during mitosis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2384. doi:10.1158/1538-7445.AM2014-2384