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Updated: May 6, 2026

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In Vitro Ubiquitination and Deubiquitination Assays of Nucleosomal Histones
Published on: July 25, 2019
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マルチウビキチン鎖の変異体による細胞周期調節によるリボソームの改変
J Spence1, R R Gali, G Dittmar
1Department of Cell Biology, Harvard Medical School, Boston, Massachusetts 02115, USA. jlspence@netscape.net
Cell
|August 10, 2000
まとめ
リボソームタンパク質L28のウビキチン改変が保存され,酵母では細胞サイクルが調節されます. このプロセスは,Lys63結合連鎖を含み,タンパク質の分解ではなく,可逆的な調節作用を示唆しています.
科学分野:
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
- バイオケミストリー バイオケミストリー
背景:
- ウビキチン改変は,細胞における重要な調節メカニズムである.
- リボソームタンパク質は,タンパク質合成と細胞機能に不可欠です.
- L28タンパク質は,大きなリボソームサブユニットの構成要素です.
研究 の 目的:
- S. cerevisiae.におけるリボソームタンパク質L28のユビキチン化を調査する.
- L28のユビキチン化に関与するユビキチン鎖の種類を決定する.
- 細胞サイクル中のL28ユビキチネーションの機能的意義を探求する.
主な方法:
- イーストのユビキチン-タンパク質結合体の分析.
- ウビキチン (Lys63からArgへの置換) のサイト指向型変異.
- 野生型および変異性ユビキチンを用いたリボソーム機能の in vivo および in vitro 評価.
主要な成果:
- L28は,S. cerevisiae.で最も豊富に存在するユビキチン-タンパク質結合体です.
- L28のユビキチネーションは細胞サイクルに依存しており,ピークはS相である.
- ユビキチネーションには,Lys63に結合したマルチユビキチン鎖が関与し,逆転可能である.
- 変異性ユビキチン (K63R) は,リボソームの機能を損なっており,トランスレーション阻害剤に対する感受性を高めます.
結論:
- L28のユビキチネーションは,保存された,細胞サイクル調節された変異です.
- L28のLys63結合ユビキチン鎖は,タンパク質の分解から独立して,規制的な役割を果たします.
- この変異は,リボソームの機能とストレスに対する細胞の反応に影響します.
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