@misc{oai:repo.qst.go.jp:00067411,
 author = {Okayasu, Ryuichi and Takahashi, Sentaro and Kubota, Yoshihisa and S., Bedford Joel and 岡安 隆一 and 高橋 千太郎 and 久保田 善久},
 month = {Jul},
 note = {We have measured the amount of DNA double strand breaks (DSBs) in Chinese hamster ovary (CHO) cells and their radiosensitive/DSB repair-deficient mutants exposed to arsenite using clamped homogenous electric field (CHEF) gel electrophoresis. Arsenite induced DNA DSB in a dose-dependent manner as observed in X-irradiated cells. However, in order to obtain the same cell survival level, about twice as many DSBs are necessary in cells treated with arsenite compared to cells exposed to x-rays. Further studies using premature chromosome condensation (PCC) technique revealed a distinct difference in how DSBs are repaired in cells exposed to arsenite as opposed to cells exposed to gamma-rays. There was no rejoining of G1-type (interphase) chromosome breaks in irradiated irs-20 cells (DNA-PKcs mutant), while there was an efficient rejoining of arsenite-induced chromosome breaks in this cell line. These results indicate that the types of DNA DSB induced by arsenite are different from those by ionizing radiation. In addition, our data for arsenite/gamma-ray combined experiments showed a significant number of mis-rejoined chromosomes in irs-20 cells, suggesting the role played by the DNA-PKcs protein in the fidelity of DNA DSB repair., ９４ｔｈ Annual Meeting},
 title = {Comparative studies on DNA damage induced by arsenite and x-rays},
 year = {2003}
}