膀性口炎ウイルスの低pH形態の結晶構造は,グリコプロテインGである

Stéphane Roche¹, Stéphane Bressanelli, Félix A Rey

¹CNRS, Unité Mixte de Recherche (UMR) 2472, Institut Fédératif de Recherche (IFR) 115, Virologie Moléculaire et Structurale, 91198, Gif sur Yvette, France.

Science (New York, N.Y.)

|July 15, 2006

まとめ

膀性口腔炎ウイルスのグリコプロテイン (G) は,膜融合に不可欠なpH依存の形状変化を経験します. そのユニークな構造は,ウイルスの進化と融合メカニズムについての洞察を明らかにします.

科学分野:

ウイルス学ウイルス学ウイルス学
構造生物学構造生物学とは
分子生物学は分子生物学である.

背景:

膀性口炎ウイルス (VSV) は,独特の膜融合グリコタンパク質 (G) を有する.
VSV Gは,ウイルスの表面上の高いと低いpHのコンフォーマーションの間のpH依存の均衡を示しています.
膜融合は,VSV G.の高pH形態から低pH形態への移行によって開始されます.

研究の目的:

VSVグリコプロテイン (G) のpH依存型構造変化の構造的基礎を解明する.
VSV G.によって引き起こされる膜融合のメカニズムを理解する.
他のウイルス融合タンパク質とVSV Gの進化的関係を調査する.

主な方法:

低pH形態のVSV Gの構造を決定するために,X線結晶学を用いた.
保存された特徴と新しい特徴を特定するために,比較構造分析が行われました.
バイオ情報分析は,他のウイルスタンパク質とのホモロジーを調査するために使用されました.

主要な成果:

VSV Gの低pH構造は,他のウイルス融合タンパク質の融合後の構造の特徴である古典的なヘアピン形状を採用しています.
VSV Gは,クラスIとクラスIIの融合タンパク質の特徴を統合した新しい折りたたみを示しています.
構造分析は,G形状の変化の可逆性を理解するためのモデルを提供します.
VSV GとヘルペスウイルスのgBグリコタンパク質の間に予想外の同質性が発見されました.

結論:

VSV Gの決定された構造は,その形状の変化の可逆性を理解するための枠組みを提供します.
この発見は,ウイルス融合タンパク質の潜在的なモザイク起源を示唆し,異なるクラスの要素を組み合わせている.
VSV Gとヘルペスウイルス gBの同質性は,ウイルスの進化と融合メカニズムの多様化に関する研究のための新しい道を開く.

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