起源認識複合体,SIR1,および静音化のためのS相要件
C A Fox1, A E Ehrenhofer-Murray, S Loo
1Department of Molecular and Cell Biology, Division of Genetics, 401 Barker Hall, University of California, Berkeley, CA 94720, USA.
Science (New York, N.Y.)
|June 6, 1997
まとめ
Saccharomyces cerevisiaeのトランスクリプションサイレンシングはDNA複製を伴う. 起源認識複合体 (ORC) とS相通過は静音化に不可欠であり,その役割は複製の開始から分離できます.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
- 細胞生物学 細胞生物学
背景:
- Saccharomyces cerevisiaeにおける転写サイレンシングは,DNA複製と関連しています.
- 起源認識複合体 (ORC) は,DNA複製の開始と転写サイレンシングの両方で役割を果たします.
- HMLとHMRの位置に静音装置を設置するには,S段階を通過する必要があります.
研究 の 目的:
- Saccharomyces cerevisiaeにおけるDNA複製と転写サイレンシングの関係を調査する.
- HMLとHMRのロケーションでの静音化におけるORCとS相の特定の役割を決定する.
- 複製開始におけるORCの機能と,転写サイレンスにおけるORCの機能を区別する.
主な方法:
- ORCが要求されない条件下でのHMR静音化のためのS相通過の要件を調査する.
- HMR-E サイレンサーに Sir1 タンパク質を繋ぐことが,ORC 依存型サイレンサーに与える影響を調べた.
- テロメアトランスクリプションサイレンシングにおけるORCのSir1独立の役割を評価する.
主要な成果:
- 複製開始におけるORCの役割とは無関係に,HMRサイレンスにはS段階を通過することが必要である.
- HMRサイレンスにおけるORCの要件は,Sir1をHMR-Eサイレンスに繋げることで回避できます.
- ORCは,テロメアトランスクリプションサイレンシングにおいて,Sir1から独立して独特な役割を果たしています.
結論:
- 転写サイレンシングにおけるORCの役割は,DNA複製の開始におけるORCの機能から分離できる.
- S相通過は,サイレンサーでの複製開始とは独立して,サイレンシングに不可欠です.
- これらの発見は,DNA複製プロセスが遺伝子サイレンシングに影響を与える明確なメカニズムを明らかにしています.
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