Molecular analysis of heavy ion induced mutations in budding yeast

出芽酵母における重イオン誘発変異の分子解析

松尾 陽一郎*; 泉 佳伸*; 長谷 純宏; 坂本 綾子; 野澤 樹; 鳴海 一成*; 清水 喜久雄*

Matsuo, Yoichiro*; Izumi, Yoshinobu*; Hase, Yoshihiro; Sakamoto, Ayako; Nozawa, Shigeki; Narumi, Issey*; Shimizu, Kikuo*

To investigate the nature of mutations induced by accelerated ions in eukaryotic cells, the effects of carbon-ion irradiation were compared with those of -ray irradiation in the budding yeast . Previous studies suggested that the mutation sites induced by carbon ions were localized near the linker regions of nucleosomes, whereas mutations induced by rays were located uniformly throughout the gene. We hypothesized that the locus of mutations might be related to the nucleosome structure. To confirm this hypothesis, we examined the mutation spectrum in the gene with the altered nucleosome structure. It is likely that sites of mutations occurred in the with altered nucleosome structure is inconsistent with those in the wild type. We will further accumulate the data to examine the above hypothesis.