結びつけるか結びつけないか:SARS-CoV-2のフレームシフトRNA要素の複数の構成
Tamar Schlick1,2,3, Qiyao Zhu2, Abhishek Dey4
1Department of Chemistry, New York University, 100 Washington Square East, Silver Building, New York, New York 10003, United States.
Journal of the American Chemical Society
|July 20, 2021
まとめ
SARS-CoV-2のフレームシフトRNAエレメント (FSE) は,想定されたH型偽ノートではなく,代替構造を使用しています. これらの構造的な洞察は,COVID-19治療の新たな治療目標を示しています.
科学分野:
- 分子生物学
- ウイルス学
- 構造生物学
背景:
- SARS-CoV-2のフレームシフトRNA要素 (FSE) は,オープン・リーディング・フレーム1aと1bの間の翻訳を調節することによって,ウイルスの複製に不可欠です.
- FSEの構造とダイナミクスを理解することは,COVID-19に対する効果的な抗ウイルス治療の開発の鍵です.
- 以前の仮説では,FSEに特有の3本のH型仮結構造が好ましいと考えられていた.
研究 の 目的:
- SARS-CoV-2 FSEの構造的状況と構成動態を調査する.
- 翻訳中にFSEによって採用された代替RNA構造を特定する.
- FSEの構造的再構成を対象とした治療的介入の可能性を調査する.
主な方法:
- グラフ理論に基づくRNA構造モデリング ("RAG" - RNA-As-Graphs) を利用した.
- 化学構造の探査実験を行いました
- 競合する構造的モチーフを特定するために,全長ウイルスゲノムを分析した.
主要な成果:
- 想定されたH型シドノット (3_6) と並行して,より長い構造のために実行可能な代替HL型3幹シドノット (3_3) を特定した.
- 小さい形状として,結び目のない3方向の交差点RNA (3_5) が観察された.
- これらの構造は,幹1と幹3を共有し,幹2の変異は,潜在的にリボソームの相互作用とコンフォメーションスイッチングを媒介する. 幹ループモチーフ (2_2) は全長ゲノムで競合する.
結論:
- SARS-CoV-2 FSEは複数の形状に存在し,以前の構造的仮定に異議を唱える.
- FSEの構造,特にステム2の変異は,リボソーム相互作用とフレームシフト効率に関係しています.
- これらの発見は,ウイルスの複製メカニズムに関する洞察を提供し,SARS-CoV-2に対する治療介入の3つの新しい方法を強調しています.
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