アルゴスによるEGFRリガンド結合の構造的基礎
Daryl E Klein1, Steven E Stayrook, Fumin Shi
1Department of Biochemistry and Biophysics, University of Pennsylvania School of Medicine, 809C Stellar-Chance Laboratories, 422 Curie Boulevard, Philadelphia, Pennsylvania 19104-6059, USA.
Nature
|May 27, 2008
まとめ
アルゴス (Argos) はドロソフィラのタンパク質で,表皮成長因子 (EGF) のリガンドを結合させ,表皮成長因子受容体 (EGFR) のシグナル伝達を阻害する. EGFRとは無関係な,クランプのような独特な構造は,抗がん療法薬の設計に潜在的可能性を秘めている.
科学分野:
- 構造生物学 構造生物学とは
- 分子生物学と細胞生物学について
- バイオケミストリー バイオケミストリー
背景:
- 皮膚表皮成長因子受容体 (EGFR) のシグナル伝達は発達に不可欠ですが,癌には関与しています.
- ドロソフィラのタンパク質であるArgosは,EGFRのリガンドを結合することによってEGFRシグナル伝達を阻害する.
- アルゴスの構造を理解することは,抗がん剤の開発の鍵です.
研究 の 目的:
- EGFRリガンドに結合したアルゴスの結晶構造を決定する.
- アルゴス媒介によるEGFRリガンド結合の分子メカニズムを解明する.
- アルゴスとその構造的同類体の潜在的な治療用途を探求する.
主な方法:
- 1.6-A解像度でのX線結晶学.
- 構造分析と既知のタンパク質ファミリーとの比較.
- 潜在的哺乳類同類を特定するためのバイオインフォマティクス.
主要な成果:
- 結晶構造は,ArgosがEGFのようなドメインではなく,3つのドメイン,クランプのような折りたたみを持っていることを示しています.
- アルゴスはEGFのリガンドを二重の表面で結合させ,EGFRの機能を模倣する.
- アルゴスドメインは,TGF-β受容体とuPA受容体と構造的に類似しています.
結論:
- Argosは,EGFRリガンドを隔離するために新しい構造的メカニズムを使用しています.
- 哺乳類のArgos同種が存在し,さらなる調査を正当化する可能性がある.
- この構造は,人工EGF隔離抗癌薬の設計のための青写真を提供します.
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