クラスBの全長グルカゴンGタンパク質結合受容体の構造
Haonan Zhang1,2, Anna Qiao1,2, Dehua Yang1,3
1CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Pudong, Shanghai 201203, China.
Nature
|May 18, 2017
まとめ
ヒトの全長グルカゴン受容体 (GCGR) の結晶構造は,その不活性な形状を明らかにする. 幹と細胞外ループを含む主要な構造要素は,GCGRにとって極めて重要です.
科学分野:
- 構造生物学
- 生物化学
- 内分泌学
背景:
- ヒトのグルカゴン受容体 (GCGR) は,グルコースホメオスタシスに不可欠なクラスBのGタンパク質結合受容体である.
- GCGRは2型糖尿病の病理生理学に関与しています.
- 以前の構造的研究は,GCGRのトランスメブラン領域に集中した.
研究 の 目的:
- 不活性な形状の全長の人間のGCGRの結晶構造を決定する.
- GCGR機能における茎と細胞外ループの構造的役割を明らかにする.
主な方法:
- X線結晶学 (3.0 Å解像度)
- 水素-デュテリウム交換
- ディスルフィードクロスリンク
- 分子ダイナミクスシミュレーション
主要な成果:
- 非活性状態の全長GCGRの結晶構造が解かれた.
- 茎領域はβ-ストランド構造を採用し,細胞外と膜外ドメインを結ぶ.
- 最初の細胞外ループは β-ヘアピンを形成し,茎と相互作用して β-シートを作成します.
- 茎と最初の細胞外ループは,リガンド結合と受容体の活性化を調節するために重要である.
結論:
- 完全長さのGCGR構造は,不活性受容体構成に関する新しい洞察を提供します.
- 茎と最初の細胞外ループは,GCGRシグナル伝達において重要な役割を果たします.
- これらの構造的特徴を理解すると,クラスBのGPCRメカニズムに関する知識が深まります.
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