| Project/Area Number |
60480137
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| Research Category |
Grant-in-Aid for General Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
General medical chemistry
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| Research Institution | Kochi Medical School |
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Principal Investigator |
SHIZUTA YUTAKA Kochi Medical School Faculity of Medicine, 医学部, 教授 (50025631)
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| Co-Investigator(Kenkyū-buntansha) |
MATSUDA MICHIKO Kochi Medical School Facility of Medicine, 医学部, 助手 (60158722)
KUROSAKI TOMOHIRO Kochi Medical School Facility of Medicine, 医学部, 助手 (50178125)
USHIRO HIROSHI Kochi Medical School Facility of Medicine, 医学部, 講師 (10151854)
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| Project Period (FY) |
1985 – 1986
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| Project Status |
Completed (Fiscal Year 1986)
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| Budget Amount *help |
¥6,700,000 (Direct Cost: ¥6,700,000)
Fiscal Year 1986: ¥1,900,000 (Direct Cost: ¥1,900,000)
Fiscal Year 1985: ¥4,800,000 (Direct Cost: ¥4,800,000)
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| Keywords | Poly(ADP-ribose) / NAD / DNA / RNA synthesis / Gene Expression / 遺伝子情報発現制御 |
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| Research Abstract |
Poly(ADP-ribose) synthetase is a chromatin-bound enzyme which synthesizes a protein-bound homopolymer of ADP-ribose utilizing NAD as a substrate. The characteristic nature of this enzyme is that it requires DNA for the catalytic activity. The enzyme is rich in malignant tumor cells as well as in normal tissues where cell proliferation is very rapid. The enzyme has been purified to homogeneity from calf thymus and human placenta. Amino acid compositions of these enzymes are very similar to each other and a monoclonal antibody as well as antisera against the calf enzyme cross-reacts with mouse, chicken and human enzymes, suggesting that the antigenic structures of poly(ADP-ribose) synthetase are highly conserved in various animal cells.
The native enzyme (M.W.=120K) is cleaved by limited proteolytic digestion into three different domains 7M.W.=44K, 22K, 54K), the first containing the site for DNA binding, the second containing the site for automodification and the third containing the site for NAD binding. The enzyme activity is partially reconstituted from the fragmented enzyme.
The DNA binding domain (M.W.=44K), like the native enzyme, has ability to preferentially suppress nick-induced random transcription initiation in a HeLa cell lysate, resulting in the production of run-off RNA initiated from the correct late promoter site on truncated DNA of adenovirus 2. The native enzyme poly(ADP-ribosyl)ates RNA polymerase II. These results, taken together, indicate that poly(ADP-ribose) synthetase plays a critical role in regulating gene expression in various eukaryotic cells.
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