title: Induction of rhodanese, a detoxification enzyme, in livers from mice after long-term irradiation with low-dose-rate gamma-rays.
abstract: The health effects of low-dose radiation exposure are of public concern. Although molecular events in the cellular response to high-dose-rate radiation exposure have been fully investigated, effects of long-term exposure to extremely low-dose-rate radiation remain unclear. Protein expression was analyzed by two-dimensional electrophoresis in livers from mice irradiated for 485 days (22 hr/day) at low-dose-rates of 0.032 microGy/min, 0.65 microGy/min and 13 microGy/min (total doses of 21 mGy, 420 mGy and 8000 mGy, respectively). One of the proteins that showed marked changes in expression was identified as rhodanese (thiosulfate sulfurtransferase). Rhodanese expression was increased after irradiation at 0.65 microGy/min and 13 microGy/min, while its expression was not changed at 0.032 microGy/min. Rhodanese is a detoxification enzyme, probably related to the regulation of antioxidative function. However, antioxidative proteins, such as superoxide dismutase (SOD)1 (also known as Cu,Zn-SOD) and SOD2 (also known as Mn-SOD), which can be induced by high-dose-rate radiation, were not induced at any low-dose-rates tested. These findings indicate that rhodanese is a novel protein induced by low-dose-rate radiation, and further analysis could provide insight into the effects of extremely low-dose-rate radiation exposure.
authors.affiliation: Radiation Effect Mechanisms Research Group, Research Center for Radiation Protection, National Institute of Radiological Sciences, Chiba, Japan. otetsu@nirs.go.jp
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Nakajima
authors.forename: Keiko
authors.initials: K
authors.lastname: Taki
authors.forename: Bing
authors.initials: B
authors.lastname: Wang
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Ono
authors.forename: Tsuneya
authors.initials: T
authors.lastname: Matsumoto
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Oghiso
authors.forename: Kimio
authors.initials: K
authors.lastname: Tanaka
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Ichinohe
authors.forename: Shingo
authors.initials: S
authors.lastname: Nakamura
authors.forename: Satoshi
authors.initials: S
authors.lastname: Tanaka
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Nenoi
mesh_terms: D000818:Animals; D004307:Dose-Response Relationship, Radiation; D005720:Gamma Rays; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology* / Q000528:radiation effects*; D008099:Liver / Q000201:enzymology* / Q000528:radiation effects*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D011829:Radiation Dosage; D013884:Thiosulfate Sulfurtransferase / Q000378:metabolism*; D014916:Whole-Body Irradiation / Q000379:methods*
chemical_list: D013884:Thiosulfate Sulfurtransferase