Proof of mutual interference between two DNA double strand break sites leading to chromosomal translocation

2017 Fiscal Year Final Research Report

• Project/Area Number: 15H02816
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Risk sciences of radiation and chemicals
• Research Institution: Gunma University
• Principal Investigator: Niimi Atsuko 群馬大学, 未来先端研究機構, 助教 (50508984)
• Research Collaborator: SHIBATA Atsushi 群馬大学, 大学院医学系研究科, 研究講師 (30707633) ; YAMAUCHI Motohiro 長崎大学, 学内共同利用施設等, 助教 (60437910)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 染色体転座 / DNA修復 / 53BP1 / DNA二本鎖切断 / 重粒子線

Outline of Final Research Achievements

We established LacO-I-SceI-TetO cell line and tried to set up a new system for monitoring chromosomal translocation, however unfortunately, it was not working well because of technical problems. It is well known that the particle irradiation more frequently causes chromosomal translocation compared with X-ray irradiation. Therefore we simultaneously visualized the site of IR-induced DSBs and chromosome position by combining Immunofluorescence and FISH after C-ion or X-rays irradiation. We found that the frequency of gH2AX foci at the chromosome boundary of chromosome 1 after C-ion irradiation was >4-fold higher than that after X-ray irradiation, and gH2AX foci at chromosome boundaries after C-ion irradiation contain DSBs undergoing DNA-end resection, which promotes repair utilizing microhomology mediated end-joining during translocation. These data suggest that the spatial proximity between breaks is an important factor in translocation formation.

Free Research Field

DNA損傷応答