カイナート亜型グルタミン酸受容体無敏感化の構造的基礎
Joel R Meyerson1, Sagar Chittori1,2, Alan Merk1
1Laboratory of Cell Biology, Center for Cancer Research, NCI, NIH, Bethesda, Maryland 20892, USA.
Nature
|September 1, 2016
まとめ
研究者らはカイナート受容体GluK2の構造を無感化状態で明らかにした. リンガンド結合ドメインの 新しい"無敏感化環"が これらの受容体が 閉じる仕組みを説明し 脳機能や病気を理解するのに 極めて重要です
科学分野:
- 神経科学
- 構造生物学
- 生物化学
背景:
- グルタミン酸受容体はシナプス伝達と認知に不可欠です
- 受容器の機能障害は様々な神経疾患に関連しています.
- 受容器のゲートメカニズム,特に無感化を理解することは不可欠です.
研究 の 目的:
- カイナート受容体GluK2の無感化状態の原子構造を決定する.
- 感受体無敏感化に伴う分子メカニズムを解明する.
- グルタミン酸受容体のゲートサイクルについての洞察を提供するためです.
主な方法:
- 構造を決定するために,冷凍電子顕微鏡 (cryo-EM) が使用されました.
- 高解像度 (3.8 Å) のGluK2カイナート受容体亜型の構造分析
- 静止状態と無感受状態の比較分析
主要な成果:
- GluK2の無感化状態は,リガンド結合ドメイン層に独特の環状構造を特徴としています.
- この"無感化リング"は,サブユニット間の段階的なヘリックス接触によって形成されます.
- リガンド結合ドメインは静止状態と異なる擬似四重対称的配置を採用する.
結論:
- GluK2 の無感化状態の重要な特徴は,無感化リング形成です.
- この構造的再編成は,形状の変化にもかかわらず,どのようにチャンネルが閉ざされているかを説明します.
- 感受器を休止状態に戻すためのスイッチは 感受器の無感化リングの障害である.
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