Visualization of heavy-ion induced clustered DNA double strand break formation using super-resolution microscopy

2016 Fiscal Year Final Research Report

• Project/Area Number: 15K15449
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Radiation science
• Research Institution: Sasaki Foundation (2016); Gunma University (2015)
• Principal Investigator: Isono Mayu 公益財団法人佐々木研究所, 附属研究所, 研究員(移行) (90713511)
• Research Collaborator: SHIBATA Atsushi 国立大学法人群馬大学, 医学系研究科, 助教 (30707633)
• Project Period (FY): 2015-04-01 – 2017-03-31
• Keywords: DNAクラスター損傷 / 重粒子線 / 染色体異常

Outline of Final Research Achievements

Heavy-ion radiation induces clustered DNA damage, which contains multiple type of DNA damage, e.g. DNA double strand break (DSB), single strand break and base damage. However so far, such clustered DNA damage has not been visualized in the cellular level. Here we aimed to visualize the clustered DNA damage, particularly about the formation of DSB, after heavy-ion radiation by using 3D super-resolution microscopy. To address the question whether heavy-ion irradiation generates clustered DSB formation or not, we monitored RPA foci as a DSB marker. The super-resolution analysis revealed that heavy-ion radiation induced multiple RPA foci in close proximity. Furthermore, our analysis demonstrated that the distance between two individual RPA foci within γH2AX foci was approximately 700 nm. In summary, our data suggests that these closely localized DSBs are considered to be a risk for chromosomal translocations, deletions and cell death after heavy-ion irradiation.

Free Research Field

放射線生物学