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Updated: Jul 19, 2026
11:24
Measuring DNA Damage and Repair in Mouse Splenocytes After Chronic In Vivo Exposure to Very Low Doses of Beta- and Gamma-Radiation
Published on: July 3, 2015
[Low-dose radiation effects and intracellular signaling pathways]
Keiji Suzuki1, Seiji Kodama, Masami Watanabe
1Division of Radiation Biology, Graduate School of Biomedical Sciences, Nagasaki University, Japan. kzsuzuki@nagasaki-u.ac.jp
Yakugaku Zasshi : Journal of the Pharmaceutical Society of Japan
|October 4, 2006
Summary
Low-dose radiation activates cellular pathways in both the membrane and nucleus. This response involves the ATM protein forming foci, indicating cells can detect and amplify signals from DNA damage.
Area of Science:
- Cellular and Molecular Biology
- Radiation Biology
- Signal Transduction
Background:
- Low-dose radiation (<0.1 Gy) causes observable effects in mammalian cells, but mechanisms are unclear.
- Low-dose radiation activates membrane-bound growth factor receptors and mitogen-activated protein kinase pathways.
- Ionizing radiation damages chromatin structure, creating DNA double-strand breaks.
Purpose of the Study:
- To investigate the molecular mechanisms underlying low-dose radiation effects on mammalian cells.
- To determine if nuclear pathways are activated by low-dose radiation.
- To characterize the role of ATM protein in sensing DNA damage from low-dose radiation.
Main Methods:
- Utilized antibodies against phosphorylated ATM to detect activated ATM protein.
- Observed ATM protein localization and formation of foci within the nucleus.
- Examined ATM foci formation across a range of radiation doses (10 mGy to 1 Gy).
Main Results:
- Activated ATM protein forms discrete foci in the nucleus following low-dose radiation exposure (10 mGy - 1 Gy).
- The size of ATM foci induced by low-dose radiation is comparable to those from high-dose radiation.
- These findings suggest signal amplification through foci growth in response to DNA damage.
Conclusions:
- Low-dose radiation is detected by both membrane and nuclear cellular components.
- Activation of multiple signal transduction pathways, including ATM-mediated nuclear signaling, is involved in cellular responses to low-dose radiation.
- Mammalian cells possess mechanisms to respond to and amplify signals from even a small number of DNA double-strand breaks.
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