1997 Fiscal Year Final Research Report Summary
Molecular Mechansims for Cellular Responses to Radiation and Oxidative Stresses
| Project/Area Number |
08458153
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
環境影響評価(含放射線生物学)
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| Research Institution | KYOTO UNIVERSITY |
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Principal Investigator |
YONEI Shuji Kyoto University, Graduate School of Science Professor, 大学院・理学研究科, 教授 (60093340)
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| Co-Investigator(Kenkyū-buntansha) |
ZHANG Qiu-Mei Kyoto University, Graduate School of Science Instructor, 大学院・理学研究科, 助手 (00260604)
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| Project Period (FY) |
1996 – 1997
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| Keywords | Glutathione / Thioredoxin / Active Oxygen Species / Redox Regulation / OxyR / Diamide / SH Oxidation |
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| Research Abstract |
We examined the pathways that thioredoxin and thioredoxin reductase protect Escherichia coli cells against hydrogen peroxide. In stationary phase, the reduced form of thioredoxin protected cells by scavenging reactive oxygen species. On the other hand, in early growth phase, the oxidized form of thioredoxin exerted as a regulatory factor for theinduction of adaptive response genes such as katG that encodes catalase- hydroperoxidase I.These effects of thioredoxin systems were mediated by the OxyR protein. In addition, the expression of the katG gene was induced by diamide under anaerobic conditions, suggesting that a disruption of redox balance results in the induction of OxyR regulon without hydrogen peroxide. Therefore, the redox state of thioredoxin is a critical factor for the redox stress response in E.coli. We examined the regulation of thioredoxin and thioredoxin reductase expression.
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