グルカゴン受容体アンタゴニストのエクストラヘリカル結合部位
Ali Jazayeri1, Andrew S Doré1, Daniel Lamb1
1Heptares Therapeutics Ltd, BioPark, Broadwater Road, Welwyn Garden City, Hertfordshire AL7 3AX, UK.
Nature
|April 26, 2016
まとめ
研究者は,X線結晶学を用いて,グルカゴン受容体 (GCGR) の新しいアロステリック結合部位を明らかにした. この発見は2型糖尿病を標的とした 構造に基づく薬の設計に 新たな道を開きます
科学分野:
- 構造生物学
- 薬理学について
- 内分泌学
背景:
- グルカゴンは,グルコースホメオスタシスに不可欠であり,グルカゴン受容体 (GCGR) を介して作用する.
- GCGR抗体が2型糖尿病の治療に有望であることが示されています.
- 以前のGCGR構造には解消されたリガンド結合部位が欠けていた.
研究 の 目的:
- 抗体と結合したヒトのGCGRの高解像度構造を決定する.
- リガンド結合部位を特定し,対抗性のメカニズムを理解する.
- GCGRを標的とする新薬の設計のための構造的基礎を提供すること.
主な方法:
- 2.5 Åの解像度でMK-0893との複合体におけるヒトGCGRのX線結晶学.
- 抗体結合に関与する主要な残基を検証するサイト指向型変異.
主要な成果:
- 抗体MK-0893は,TM6とTM7の間の7TMバンドルの外にある新しいアロステリックサイトに結合する.
- ミュタゲネシスは,MK-0893の結合における確認された残留物の役割を確認した.
- 結合メカニズムは,TM6の動きを制限することで,グルカゴン誘発の受容体活性化を防ぐことを示唆している.
結論:
- GCGRアンタゴニストのための新しいアロステリック結合部位が特定されました.
- この発見は,クラスBのGタンパク質結合受容体活性化メカニズムの理解を進めている.
- この構造は,GCGRおよび関連する受容体のための構造ベースの薬剤設計の基礎を提供します.
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