X線構造はヒトP2X(3) 受容器ゲートサイクルと対抗作用を定義する
Steven E Mansoor1,2, Wei Lü1, Wout Oosterheert1
1Vollum Institute, Oregon Health &Science University, Portland, Oregon 97239, USA.
Nature
|September 15, 2016
まとめ
研究者は最初のヒトP2X3受容体の構造を明らかにし,開いた状態と閉じた状態を詳細に説明しました. これらの発見はATPゲートイオンチャネルメカニズムを明らかにし,新しい治療薬の設計にインフォームします.
科学分野:
- 構造生物学
- 分子薬理学
- イオンチャネル研究
背景:
- P2X受容体は,心血管,神経,免疫機能に関わる重要なATPゲートイオンチャネルである.
- ヒトのP2X受容体構造とゲートメカニズムは,その重要性と治療的可能性にもかかわらず,ほとんど不明のままである.
研究 の 目的:
- 人間のP2X3受容体の機能の構造的基礎を明らかにし,ゲーティング,無感化,および対抗性を含む.
- 様々な機能状態のヒトP2X3受容体の高解像度構造を提供する.
主な方法:
- ヒトのP2X3受容体の構造を決定するために,X線結晶学を用いた.
- 構造は,アポ/休息状態,アゴニスト結合/開いた孔,アゴニスト結合/閉じた孔/無感化状態,およびアンタゴニスト結合/閉じた状態で得られた.
主要な成果:
- 開いた状態の構造は,毛穴とユニークな細胞膜を安定させる"細胞膜蓋"のモチーフを明らかにします.
- コンペティティブアンタゴニストであるTNP- ATPとA-317491が静止状態を安定させ,抑制メカニズムを明らかにすることが観察されました.
- 構造は,P2X受容体のゲート化と脱敏感化に伴う重要な形状の変化を示しています.
結論:
- 決定された構造は,ヒトのP2X3受容体の構造動態に関する前例のない洞察を提供します.
- これらの発見は,P2X受容体を標的とする新薬の開発のための基礎を築いた.
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