Study on radiation-induced mutagenesis in a bacterial population

2022 Fiscal Year Final Research Report

• Project/Area Number: 17K20052
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Research Field: Environmental analyses and evaluation and related fields
• Research Institution: National Institutes for Quantum Science and Technology
• Principal Investigator: Shikazono Naoya 国立研究開発法人量子科学技術研究開発機構, 量子生命科学研究所, 上席研究員 (10354961)
• Co-Investigator(Kenkyū-buntansha): 酒井 真理 群馬大学, 大学院医学系研究科, 助教 (70727338)
• Project Period (FY): 2017-06-30 – 2023-03-31
• Keywords: 突然変異 / ストレス / 放射線

Outline of Final Research Achievements

Although the response of a cell population to irradiation is expected to be heterogeneous in a cell population, it was not clear how the mutagenic potential is altered by the physiological conditions of individual cells. The present study reveals that growth stress can alter mutation frequency, and that irradiation can further increase mutation frequency and change the spectrum of mutations. On the other hand, in some cases there was no significant change in mutation frequency, suggesting that the physiological conditions and responses of the cells may be intricately involved. These results indicate that the physiological conditions within the cell are altered by the surrounding environment, and that these changes significantly affect radiation-inudced mutagenesis.

Free Research Field

放射線生物学

Academic Significance and Societal Importance of the Research Achievements

細胞内の生理条件という新たな研究視点を取り入れて突然変異の全体像に迫った本研究は、細菌の薬剤抵抗性獲得・発がんの初期過程・進化等における突然変異誘発機構の理解のための第一歩であり、学術的意義は高い。特に、放射線誘発突然変異と発がんに関しては、放射線治療における二次発がんの抑制や放射線リスク評価に極めて重要な示唆を与えると考えられるため、将来的に社会的インパクトの極めて大きい成果につながることが期待できる。また、本研究では細胞増殖が速く突然変異研究に向いているモデル生物の大腸菌を用いているが、他の生物種での研究の基盤を築くことができたと考えられる。