遺伝子の重複により,RNA結合ドメインと主要なコートタンパク質ドメインを持つウイルスタンパク質が生成されます
1Section on Genetics of Simple Eukaryotes, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland 20892.
Cell
|November 18, 1988
まとめ
研究者らは,酵母ウイルスのような粒子 (VLPs) の特定のタンパク質が単一鎖RNA (ssRNA) に結合し,二鎖RNA (dsRNA) の複製に不可欠であることを発見しました. このタンパク質は,L-A dsRNAゲノムによってコードされています.
科学分野:
- 分子ウイルス学 分子ウイルス学
- イースト遺伝学 イースト遺伝学
- RNAレプリケーション RNA複製
背景:
- L-A二重鎖RNA (dsRNA) は,保守的で非同期的なプロセスを通して,酵母ウイルスのような粒子 (VLPs) の内に複製します.
- 新しいウイルス粒子は,新たに合成された (+) 糸を包装することによって組み立てられます.
研究 の 目的:
- イーストにおけるL-A dsRNA複製と粒子の形成のメカニズムを調査する.
- VLP内のRNA結合と複製に関与する宿主因子とウイルスタンパク質を特定する.
主な方法:
- ウイルスの (+) 単一鎖RNA (ssRNA) を,孤立したVLPと宿主因子を用いてdsRNAに in vitro変換する.
- ウェスタン・ブロットを用いたVLPタンパク質のssRNA結合活性の分析.
- 180 kDaのタンパク質と主要なコートタンパク質とL-A (+) 鎖配列の免疫学的比較.
主要な成果:
- 空のVLPは,ウイルス (+) ssRNAに特異的に結合し,宿主因子との結合は,in vitroでdsRNAの合成につながります.
- 隔離された結合複合体は,宿主因子の存在で形成された場合にのみ複製します.
- VLPマイナー180 kDaタンパク質はssRNA結合活性を示し,主要なコートタンパク質とL-A (+) 鎖との抗原ドメインを共有しており,L-A dsRNAによってコードされていることを示しています.
結論:
- L-A dsRNAゲノムは,主要なコートタンパク質ドメインとssRNA結合ドメインの両方を含む180 kDaのタンパク質をコードします.
- この180 kDaのタンパク質は,酵母VLPs内のssRNAの特定の結合およびその後のdsRNA複製に不可欠であり,宿主因子が必要です.
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