26SプロテアソームによるNF-kappaB p50のコトランスレーションバイオゲネシス
L Lin1, G N DeMartino, W C Greene
1Gladstone Institute of Virology and Immunology, Department of Microbiology and Immunology, University of California, San Francisco 94141, USA.
Cell
|April 7, 1998
まとめ
NFkappaB1遺伝子は,新しいコトランスレーションプロセスを通して,p50とp105という2つのタンパク質を生成します. このメカニズムは,これらの重要なNF-kappaB経路タンパク質のバランスのとれた生産と独立した機能を保証します.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝子規制 遺伝子規制
- タンパク質生化学 タンパク質生化学
背景:
- NFkappaB1遺伝子は,p50とp105.5という2つのタンパク質をコードしています.
- p50はp65 (RelA) とともにNF-kappaB転写因子複合体を形成する.
- p105はp50の前駆体として提案されており,Rel-specific inhibitor (IKB) として作用しています.
研究 の 目的:
- NFkappaB1遺伝子からのp50およびp105タンパク質生成のメカニズムを解明する.
- p50 と p105.5 の関係を調べる
- NF-kappaB経路のコンポーネントの規制を理解するために.
主な方法:
- 調査されたNFkappaB1.1.の共同翻訳処理
- タンパク質生成の研究で26Sプロテアソームを利用した.
- p50.0.のC端の近くのタンパク質の折り畳みを分析した.
主要な成果:
- p50は,26Sプロテアソームが関与するユニークなコトランスレーション処理イベントによって生成されます.
- p50のC端の近くのコトランスレーション折り合いは,プロテアソームの処理を妨げ,p105の生成につながります.
- p105はp50.の前駆体ではない.
結論:
- 新しい遺伝子調節メカニズムは,p50とp105.5のバランスのとれた生産を保証します.
- p50 と p105 は,コトランスレーション処理によって調整される独立した機能を備えています.
- この発見は,p105.5からp50生成の前駆者モデルに異議を唱えている.
キーワード:
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