アポプトティックプロテアゼ活性化因子1によるプロカスペーゼ9の募集の構造的基礎
1Department of Chemistry, Princeton University, New Jersey 08544, USA.
Nature
|June 22, 1999
まとめ
アポトーシスはカスパース9によって調節され,カスパース9はApaf-1によって活性化されます. 構造分析は,このカスパース-9活性化プロセスと他の生物体での保存に不可欠な特定の分子相互作用を明らかにします.
科学分野:
- バイオケミストリー バイオケミストリー
- 分子生物学は分子生物学である.
- 構造生物学 構造生物学とは
背景:
- カスパゼ9媒介のアポプトシスは,多細胞生物の発達と恒常性のために不可欠です.
- 成熟したカスパゼ-9は,そのプロカスパゼ前駆体から,Apaf-1によるリクルートによって生成される.
研究 の 目的:
- Apaf-1とプロカスペーゼ-9の相互作用の構造的基礎を解明する.
- カスパース-9の活性化特異性の基礎にある分子機構を理解する.
主な方法:
- X線結晶学により,Apaf-1のカスパゼ募集ドメインと,その複合体とプロカスパゼ-9プロドメインの構造を決定する.
- サイト・ディレクテッド・ミュータジェネシス (Site-directed mutagenesis) で,インターフェース残留物の役割を調査する.
- プロカスペーゼ-9の活性化を評価するためのセルフリーシステム.
- Caenorhabditis elegans.の同類体の比較分析について
主要な成果:
- 結晶構造は,2つの充電された互補の表面を明らかにし,水素結合とヴァン・デル・ワールス力を通してApaf-1とプロカスペーゼ-9の相互作用を媒介した.
- 鍵となるインターフェース残留物の変異は,in vitroでプロカスペーゼ-9の活性化に障害をもたらした.
- 野生型のプロドメインは,プロカスペーゼ-9処理を阻害し,突然変異体はそうしなかった.
- ホモローグ分析では,保存された構造的モチーフがCED-4によるCED-3の採用を媒介することを示唆しています.
結論:
- Apaf-1とプロカスペーゼ-9の間の特定の分子間相互作用は,正確な活性化に不可欠です.
- これらの相互作用のメカニズムは,種間で保存され,それらの基本的な生物学的重要性を強調しています.
関連する概念動画
Apoptosis
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Normal cells contain receptors that prevent them from being recognized by phagocytes.
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Cells respond to damage and stress through highly coordinated processes that decide whether they survive or undergo controlled self-destruction. Two major pathways involved in this regulation are apoptosis, a type of programmed cell death, and autophagy, a survival mechanism that helps cells adapt to adverse conditions.ApoptosisApoptosis removes aged or injured cells to maintain tissue balance. During this process, the cell shrinks, chromatin condenses and fragments, and membrane-bound...


