セリンは,天然のリガンドであり,ピルーバートキナーゼM2のアロステリック活性化剤である
Barbara Chaneton1, Petra Hillmann2, Liang Zheng1
1Cancer Research UK, The Beatson Institute for Cancer Research, Switchback Road, Glasgow, G61 1BD, Scotland, United Kingdom.
Nature
|October 16, 2012
まとめ
がん細胞 がん細胞 がん細胞
科学分野:
- バイオケミストリー バイオケミストリー
- 細胞生物学 細胞生物学
- 代謝経路について
背景:
- 癌細胞は,成長に不可欠な異なった代謝現象型を示します.
- ピルバ酸キナーゼM2 (PKM2) の過剰発現とセリン/グリシン生物合成への依存が鍵となる.
- PKM2の活性とセリン合成の相互作用は完全に理解されていません.
研究 の 目的:
- PKM2の活性と新たなセリン生物合成のメカニズム的な関係を解明する.
- 癌細胞におけるPKM2機能の調節におけるセリンの役割を調査する.
主な方法:
- PKM2の活性を測定するための生化学的測定法.
- セリン欠乏とサプリメントを含む細胞実験.
- 糖分由来炭素を追跡するための代謝流量分析.
主要な成果:
- セリンはヒトPKM2.2に直接結合し,活性化させます.
- PKM2の活動は,がん細胞におけるセリン欠乏によって著しく低下する.
- 減少したPKM2活性により,ピルバートはミトコンドリアに転送され,セリン生物合成が強化されます.
結論:
- 新しいレオスタットのようなメカニズムは,PKM2の活性とセリン生物合成を結びつける.
- この代謝の再プログラミングは,栄養素の利用可能性の下での癌細胞の増殖をサポートします.
- この経路をターゲットにすることで,がんに対する新しい治療戦略を提供することができる.
関連する概念動画
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