EGF受容体の活性化において,プラズマ膜を横断する適合結合
Nicholas F Endres1, Rahul Das, Adam W Smith
1Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA.
Cell
|February 5, 2013
まとめ
皮膚表皮成長因子受容体 (EGFR) の活性化は,その表面密度に依存する. EGF結合はステリック制約を解除し,トランスメブランヘリックス相互作用と受容体の活性化を促進します.
科学分野:
- バイオケミストリー バイオケミストリー
- 細胞生物学 細胞生物学
- 分子生物学は分子生物学である.
背景:
- 皮膚表皮成長因子受容体 (EGFR) の活性化メカニズムは完全に理解されていません.
- EGFRの細胞内領域は,溶液中の固有の活性を示します.
研究 の 目的:
- EGFR活性化の調節を調査する.
- EGFRの表面密度の自己リン酸化における役割を決定する.
主な方法:
- 細胞の表面密度の関数としてEGFR自己リン酸化の測定.
- ディメリゼーションを評価するために,光交差相関スペクトロスコーピー.
- 核磁共振 (NMR) と機能的測定法. 核磁共振 (NMR) と機能的測定法. 核磁共振 (NMR) と機能的測定法. 核磁共振 (NMR) と機能的測定法. 核磁共振 (NMR) と機能的測定法.
主要な成果:
- EGFRは,EGFなしで高表面密度でのみ抑制から逃れることができます.
- トランスメブランヘリックスと細胞内モジュールは,共同で構成的活動を可能にします.
- 隔離された細胞内モジュールは不活性化され,膜に結合すると二元化することができません.
- アクティベーションには,N端のトランスメブランヘリックス相互作用が必要であり,柔膜セグメントの相互作用と膜の解放を促進します.
結論:
- EGFの結合は,細胞外硬化制約を緩和する.
- これは,トランスメブランヘリクスのN端結合経由での活性化を促します.
- EGFRの活性化は,リガンド結合と受容体の表面密度の両方によって調節されます.
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