ディメリゼーションによる受容体タンパク質-チロシン・フォスファタゼ-アルファの抑制のための構造的基礎
A M Bilwes1, J den Hertog, T Hunter
1Structural Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, California 92037, USA.
Nature
|August 8, 1996
まとめ
受容体型のタンパク質・チロシン・フォスファタゼ (RPTPs) の活動は,二分化によって調節される. 構造分析によると,N端セグメントは活性部位をブロックし,RPTP機能をダウンレギュレーションする可能性がある.
科学分野:
- バイオケミストリー バイオケミストリー
- 構造生物学 構造生物学とは
- 細胞シグナル伝達 細胞信号伝達
背景:
- 受容体型のタンパク質チロシンフォスファタゼ (RPTPs) は,フォスフォチロシンレベルを調節する統合膜タンパク質です.
- 彼らの触媒的活動と細胞外リガンドによる調節は,ほとんど特徴づけられていないままである.
研究 の 目的:
- RPTP規制の構造的根拠を解明する.
- RPTPalphaの触媒活性制御のメカニズムを調査する.
主な方法:
- ミュアンのRPTPalpha膜近接触媒ドメインの結晶構造の決定 (D1).
- 既知の PTP1B 折りたたみからの構造的偏差の分析.
- EGF受容体/CD45キメラの研究からのデータの配列調整と統合.
主要な成果:
- RPTPalphaD1において,N端のヘリックス・ターン・ヘリックス・セグメントとユニークなベータシートを含む,重要な構造的偏差を特定した.
- ダイアード関連D1モノメールの活性部位にN末端セグメントの挿入を観察した.
- ダイメリゼーションを媒介するアクティブサイトブロックメカニズムの証拠を提供した.
結論:
- RPTPの二分化とその後の活性部位の阻害は,RPTPアルファおよび他のRPTPをダウンレギュレーションするための重要なメカニズムであると提案します.
- 細胞外リガンドから独立したRPTPの新たな調節経路を示唆している.
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