PB-08-23: Unravelling the mechanisms of the effects of low-dose ionising radiation on living systems

Life on Earth has evolved under constant exposure to background ionising radiation, which has become an integral part of the environment of all living organisms. The linear no-threshold model, used to assess the risks of exposure to ionising radiation, suggests that even small doses of radiation can be harmful. However, experiments in underground laboratories have shown that an environment with a low radioactive background has a negative effect on living systems. The mechanisms behind this phenomenon are still unknown, but the results of most experiments suggest that, after the conditioning period in a low-radiation environment, cells show a reduced ability to repair DNA when exposed to DNA-damaging agents (chemicals, irradiation).

However, it is unknown whether the sensitivity of conditioned organisms to DNA damage is direct, due to deficiencies in DNA repair mechanisms, or indirect, due to reduced efficiency of ROS scavenging species (reactive oxygen species, ROS).

This proposal aims to study how a low-radiation environment can contribute to alterations in subcellular enzymatic reactions, mitochondrial function, and direct and indirect DNA damage. To this end, chemical enzymatic reactions involved in cellular protection against oxidative damage, and mitochondrial function in yeast, will be studied in this underground environment.