Effects of Low- and High-LET Radiation on the Salt Chemotaxis Learning in Caenorhabditis elegans

摘要

High linear energy transfer (LET) radiation is important components of cosmic rays that has neurobiological effects: it is known to induce conditioned taste aversion, and suppress neurogenesis that may underlie cognitive impairment. However, the impact of high-LET radiation on other learning effects remains largely unknown. Here, we focus on kinetics of the radiation response for the salt chemotaxis learning (SCL) behavior in the nameatode, Caenorhabditis elegans , because the SCL during the learning conditioning was modulated after low-LET γ-irradiation. Firstly, the SCL ability was examined following high-LET irradiation (~(12)C, 18.3 MeV/u, LET = 113 keV/μm), revealing its dose-dependent decrease after high- and low-LET exposure. Next, we demonstrate that the SCL at the early phase of the learning conditioning is greatly affected by high- and low-LET irradiation, and interestingly, the magnitude of these effects by high-LET radiation was significantly smaller than that by low-LET one. Moreover, the analysis of gpc-1 mutant showed that the G-protein γ subunit, GPC-1 is responsible for such early phase response. This study is the first to provide the evidence for the kinetics of changes in SCL after high-LET irradiation of C. elegans .