Hydrogen acts as a new class of radioprotective agent for space radiation-induced DNA damage
- Paper number
IAC-15,A1,5,8,x31215
- Author
Dr. Qiao Sun, CAST, China
- Coauthor
Dr. Fei Li, Beijing Space Bio-technology Research Center, China Academy of Space Technology (CAST), China
- Year
2015
- Abstract
Ionizing radiation (IR) is a known mutagen responsible for causing DNA strand breaks in all living organisms. Strand breaks thus created can be repaired by different mechanisms, including homologous recombination (HR), one of the key mechanisms maintaining genome stability.Here, we used previously generated Arabidopsis thaliana, transgenic for homologous recombination reporter system, in which HR frequency（HRF） was used as mutagenic end points. Based on the system, effect of DNA damage by space-flight during the Shenzhou-9 mission was investigated and the results showed that 13 days space-flight exposure of seedlings induced a significant increase in HRF compared with its ground-base three-dimensional clinostat controls and ground 1g controls. We also observed three-dimensional clinostat induced a significant increase in HRF compared with ground 1g controls. Molecular hydrogen (H2) has antioxidant activities by selectively reducing •OH and peroxynitrite(ONOO-), so we investigated the effect of hydrogen on IR-induced HRF. Treatment with the ROS scavenger hydrogen-rich water dramatically reduced the HR frequency induced by exposure of seedlings to 0 to 20.0 Gy 60Co, suggesting that hydrogen represents a potentially novel preventative strategy for radiation-induced oxidative injuries in plants.
- Abstract document
- Manuscript document
(absent)