LET dependence of radiation-induced biological effects in plant cells

Yokota, Yuichiro; Hase, Yoshihiro; Inoue, Masayoshi; Narumi, Issei; Funayama, Tomoo; Kobayashi, Yasuhiko; Tanaka, Atsushi

To consider LET effects is necessary for making clear the influence of environmental radiation to organisms, because high-LET radiation such as -rays are included. In this study, we thus analyzed cell killing effect and DNA double-strand break (DSB) induction in tobacco cultured cells irradiated with high-LET heavy ions. As a result, cell killing effect and DSB induction per irradiated dose reached to maximum by the irradiation of carbon ions with LETs of 247 and 124-241 keV/m respectively. These findings were different from the LET dependencies that have been reported in mammalian cells and yeasts, suggesting that only data accumulated using mammals and yeasts are insufficient to decide the radiation impacts to all organisms.