セムリキ・フォレストウイルスとその受容体VLDLRとの複合体の構造
Duanfang Cao1, Bingting Ma2, Ziyi Cao3
1National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences (CAS), Beijing 100101, China.
Cell
|April 25, 2023
まとめ
セムリキ・フォレストウイルス (SFV) は,非常に低密度の脂質タンパク質受容体 (VLDLR) を使用して感染します. クリオ・エムがVLDLRを検出する
科学分野:
- ウイルス学
- 構造生物学
- 生物化学
背景:
- セムリキ森林ウイルス (SFV) はアルファウイルスです.
- SFVは,脊椎動物の宿主と昆虫のベクトルの両方の細胞への侵入のために非常に低密度の脂質タンパク質受容体 (VLDLR) を利用します.
- この相互作用の分子基盤を理解することは,抗ウイルス戦略の開発に不可欠です.
研究 の 目的:
- VLDLRと複合してSFVの高解像度構造を解明する.
- SFVとVLDLRの特定の結合部位と相互作用メカニズムを特定する.
- SFV結合におけるVLDLRのLDLRクラスA (LA) リピートの役割を調査する.
主な方法:
- SFV-VLDLR複合体の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.
- ウイルスのタンパク質とVLDLRのインターフェースを特徴付けるために構造分析が行われました.
- 異なるVLDLR領域の貢献を評価するために,拘束力のある親和研究が行われました.
主要な成果:
- VLDLRは,その膜-遠隔のLDLRクラスA (LA) リピートを通して,SFV表面上の複数のE1-DIIIサイトに結合する.
- LA3リピートは,SFVに対する最も高い結合親和性を表している.
- 相互作用には,主要な塩橋構造を持つ小さなインターフェース (378 Å2) が含まれる.
- 単一のLA3ではなく,連続したLAの繰り返しは,回転調整を通じて,複数のウイルスサイトとの相互作用を可能にします.
結論:
- VLDLRがSFVと結合するメカニズムは,複数のLAの繰り返しによって仲介されるシネジスティックな相互作用によって特徴付けられます.
- この多価結合は親和性を高め,様々な種のVLDLRがSFVと結合することを可能にします.
- 発見は,アルファウイルス受容体相互作用と治療介入の潜在的な標的に関する構造的な洞察を提供します.
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