1993 年度実績報告書

放射線損傷の発現とそれを修飾する修復機構の研究

研究課題

研究課題/領域番号	04304056
研究機関	放射線医学総合研究所
研究代表者	佐藤弘毅放射線医学総合研究所, 障害基礎研究部, 部長 (60029775)
研究分担者	高木信夫北海道大学大学院, 地球環境科学研究科, 教授 (20001852) 嶋昭紘東京大学, 理学部, 教授 (60011590) 瀬野悍二国立遺伝学研究所, 変異遺伝研究部門, 教授 (30076989) 二階堂修金沢大学, 薬学部, 教授 (60019669) 安井明東北大学, 加齢医学研究所・神経機能情報研究分野, 助手 (60191110)
キーワード	DNA鎖切断 / 光回復酵素 / 除去修復 / 紫外線皮膚癌 / 生殖細胞突然変異 / X染色体不活性化 / しきい線量 / クローナリティ
研究概要	哺乳類細胞の電離放射線感受性変異株を数種類分離して、それらはDNA二本鎖切断の再結合能が低下していることを示した。DNA一本鎖切断の再結合には速修復と遅修復とがあり、野生株に比べて、ある変異株では速修復が欠損しているが、別の変異株では正常であることを明らかにした。魚、昆虫、有袋類の光回復酵素遺伝子を単離し、塩基配列を決定して、機能領域を推定した。ヒト除去修復遺伝子ERCC5を単離し、その塩基配列から色素性乾皮症G群の遺伝子であることを示した。実験動物を用いた紫外線皮膚発癌系を確立し、Tリンパ球とナチュラルキラー(NK)細胞の関与をそれぞれを欠損しているnudeとbeigeマウスを用いて検討し、低線量照射による発癌はNK活性によって抑制されることを示した。また、マウス皮膚に生じた紫外線損傷のチミン二量体と(6-4)産物はいずれも24時間以内に消失することを明らかにした。ユビキチン活性化酵素のある温度感受性変異株は制限温度に保温すると、細胞周期のG2期に停止し、染色体の部分的細粉化が起こることを発見した。メダカの生殖細胞突然変異を調べて、自然生存突然変異率はマウスと有意差がなく、誘発突然変異率は分化・成熟の段階によって大きく変化することを示した。マウスのXXY胚で過剰Xが父親由来の場合は正常に発育するが、母親由来の場合は発生異常を認め、これはX染色体の不活性化に起因することを証明した。ベータ線反復照射による皮膚発癌にはしきい線量が存在し、そこではerror-free repairが働いていることを明らかにした。さらに癌抑制遺伝子p53の突然変異を分析した。放射線誘発前リンパ腫は単一細胞由来が多いが、複数細胞由来もあり、クローン特異的染色体異常も認められた。急性白血病などの女性について制限断片長多型を利用したクローン分類に成功し、異常クローン検出への応用が期待される。

研究成果
(17件)

すべてその他

すべて文献書誌 (17件)

[文献書誌] Warters,R.I....Sato,K.: "DNA-damage processing in a radiation -sensitive mouse cell line." Mutation Research. 293. 91-98 (1993)
[文献書誌] Stackhouse,M.A....Sato,K.: "Functional complementation of the radiation-sensitive mutant M10 cell line by human chromosome 5." Mutation Research. 323. 47-52 (1994)
[文献書誌] van Vuuren,A.J....Yasui,A.: "Evidence for a repair enzyme complex involving ERCC1 and complementing activities of ERCC4,ERCC11 and xeroderma pigmentosum group F." EMBO Journal. 12. 3693-3701 (1993)
[文献書誌] Miki,K....Yasui,A.: "Crystallization and preliminary X-ray diffraction studies of photolyase from the cyanobacterium Anacystis nidulans." Journal of Molecular Biology. 233. 167-169 (1993)
[文献書誌] Numata,M....Shiomi,T.: "Identification of cellular defect in UVS1, a UV-sensitive Chinese hamster ovary mutant cell line." Cancer Research. 53. 495-499 (1993)
[文献書誌] Shiomi,T.: "An ERCC5 gene with homology toyeast RAD2 is involved in group G xeroderma pigmentosum." Mutation Research. (in press). (1994)
[文献書誌] Nikaido,O.: "Identification of various photoproducts in DNA exposed to solar light by damage-specific monoclonal antibodies." Photomedicine and Photobiology. 15. 21-24 (1993)
[文献書誌] Matsunaga,T....Nikaido,O.: "Establishment and characterization of a monoclonal antibody recognizing the Dewar isomers of (6-4)photoproducts." Photochemistry and Photobiology. 57. 934-940 (1993)
[文献書誌] Yamao,F....Seno,T.: "Conditional resistance to thymineless death predominantly selects DNA synthesis-deficient mutants of mammalian cells." Mutation Research. 289. 83-89 (1993)
[文献書誌] Takagi,N.: "Variable patterns of X chromosome inactivation in near-tetraploid murine EC somatic cell hybrid cells differen-tiated in vitro." Genetica. 88. 107-117 (1993)
[文献書誌] Tada,T....Takagi,N.: "X chromosome retains the memory of its parental origin in murine embryonic stem cells." Development. 119. 813-821 (1993)
[文献書誌] Tada,T....Takagi,N.: "Parental imprinting on the mouse X chromosome: effects on the early development of XO, XXY and XXX embryos." Genetical Research. 62. 139-148 (1993)
[文献書誌] Ootsuyama,A....Tanooka,H.: "Effect of an inhibitor of tumor promotion,alpha-difluoro-methylornithine, on tumor induction by repeated beta irradiation in mice." Japanese Journal of Cancer Research. 84. 34-36 (1993)
[文献書誌] Ootsuyama,A....Tanooka,H.: "Zero tumor incidence in mice after repeated lifetime exposures to 0.5 Gy of beta irradiation." Radiation Research. 134. 244-246 (1993)
[文献書誌] Shimizu,T....Muto,M.: "Multiple pre-neoplastic events and clonal selection of radiation induced mouse thymic lymphoma shown by TCR gene rearrangements." Leukemia Research. 17. 959-965 (1993)
[文献書誌] Jinnai,I....Hirashima,K.: "A clonal study of hematopoiesis using M27 probe: aberrant band-patterns by incomplete digestion of a methyl-sensitive enzyme in the inactive X-chromosome." Leukemia. 7. 1432-1436 (1994)
[文献書誌] Yasui,A.: "Frontiers of Photobiology(eds. Shima,A.et al.)Primary structures of photolyases from microorganisms." Excerpta Medica (Amsterdam), 355-356 (1993)

1993 年度 実績報告書

放射線損傷の発現とそれを修飾する修復機構の研究

研究代表者

佐藤 弘毅 放射線医学総合研究所, 障害基礎研究部, 部長 (60029775)

研究成果

[文献書誌] Warters,R.I....Sato,K.: "DNA-damage processing in a radiation -sensitive mouse cell line." Mutation Research. 293. 91-98 (1993)

[文献書誌] Stackhouse,M.A....Sato,K.: "Functional complementation of the radiation-sensitive mutant M10 cell line by human chromosome 5." Mutation Research. 323. 47-52 (1994)

[文献書誌] van Vuuren,A.J....Yasui,A.: "Evidence for a repair enzyme complex involving ERCC1 and complementing activities of ERCC4,ERCC11 and xeroderma pigmentosum group F." EMBO Journal. 12. 3693-3701 (1993)

[文献書誌] Miki,K....Yasui,A.: "Crystallization and preliminary X-ray diffraction studies of photolyase from the cyanobacterium Anacystis nidulans." Journal of Molecular Biology. 233. 167-169 (1993)

[文献書誌] Numata,M....Shiomi,T.: "Identification of cellular defect in UVS1, a UV-sensitive Chinese hamster ovary mutant cell line." Cancer Research. 53. 495-499 (1993)

[文献書誌] Shiomi,T.: "An ERCC5 gene with homology toyeast RAD2 is involved in group G xeroderma pigmentosum." Mutation Research. (in press). (1994)

[文献書誌] Nikaido,O.: "Identification of various photoproducts in DNA exposed to solar light by damage-specific monoclonal antibodies." Photomedicine and Photobiology. 15. 21-24 (1993)

[文献書誌] Matsunaga,T....Nikaido,O.: "Establishment and characterization of a monoclonal antibody recognizing the Dewar isomers of (6-4)photoproducts." Photochemistry and Photobiology. 57. 934-940 (1993)

[文献書誌] Yamao,F....Seno,T.: "Conditional resistance to thymineless death predominantly selects DNA synthesis-deficient mutants of mammalian cells." Mutation Research. 289. 83-89 (1993)

[文献書誌] Takagi,N.: "Variable patterns of X chromosome inactivation in near-tetraploid murine EC somatic cell hybrid cells differen-tiated in vitro." Genetica. 88. 107-117 (1993)

[文献書誌] Tada,T....Takagi,N.: "X chromosome retains the memory of its parental origin in murine embryonic stem cells." Development. 119. 813-821 (1993)

[文献書誌] Tada,T....Takagi,N.: "Parental imprinting on the mouse X chromosome: effects on the early development of XO, XXY and XXX embryos." Genetical Research. 62. 139-148 (1993)

[文献書誌] Ootsuyama,A....Tanooka,H.: "Effect of an inhibitor of tumor promotion,alpha-difluoro-methylornithine, on tumor induction by repeated beta irradiation in mice." Japanese Journal of Cancer Research. 84. 34-36 (1993)

[文献書誌] Ootsuyama,A....Tanooka,H.: "Zero tumor incidence in mice after repeated lifetime exposures to 0.5 Gy of beta irradiation." Radiation Research. 134. 244-246 (1993)

[文献書誌] Shimizu,T....Muto,M.: "Multiple pre-neoplastic events and clonal selection of radiation induced mouse thymic lymphoma shown by TCR gene rearrangements." Leukemia Research. 17. 959-965 (1993)

[文献書誌] Jinnai,I....Hirashima,K.: "A clonal study of hematopoiesis using M27 probe: aberrant band-patterns by incomplete digestion of a methyl-sensitive enzyme in the inactive X-chromosome." Leukemia. 7. 1432-1436 (1994)

[文献書誌] Yasui,A.: "Frontiers of Photobiology(eds. Shima,A.et al.)Primary structures of photolyases from microorganisms." Excerpta Medica (Amsterdam), 355-356 (1993)

1993 年度実績報告書

佐藤弘毅放射線医学総合研究所, 障害基礎研究部, 部長 (60029775)