Grant: Discovery Grants Program - Individual

Historically, the biological effects of low-dose radiation were estimated by extrapolating from the biological effects of high-dose radiation on Japanese atomic-bomb survivors, groups of exposed uranium miners, radium painters, or nuclear submarine builders. This extrapolation postulates that any dose no matter how small is potentially harmful. However, it was recently shown that the biological effects of low-dose radiation are considerably more complex. Living organisms have great capacity to 'withstand' or 'adapt' to radiation. Adaptive response is defined as the acquired radio-resistance after irradiation with low doses. In my NSERC funded project we have shown that plants can adapt to chronic irradiation and life in Chernobyl area by substantially re-shaping their genomes. The phenomenon of radioadaptation of mammalian species has not been sufficiently explored. Molecular mechanisms of mammalian adaptation to low dose radiation are the focus of my NSERC renewal. In collaboration with the researchers of the Chernobyl Scientific Center we will address the molecular and cellular changes in the laboratory mice subjected to low dose radiation exposure. The following questions will be addressed: What is the molecular nature of low dose radiation-induced effects in the cell? Does adaptive response induced by radiation exposure of mammalian cells exist and what are the mechanisms triggering it? Which roles do epigenetic changes (DNA methylation, histone modifications, miRNAome changes) play in radiation adaptation? This project should result in a solid understanding of basic radioadaptive processes, cellular physiology, genotoxic stress responses and molecular evolution.