ポリーア) ポリメラーゼと,ワクチンウイルスによって暗号化された解離性ポリアデニレーション刺激因子
P D Gershon1, B Y Ahn, M Garfield
1Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892.
Cell
|September 20, 1991
まとめ
研究者らは,mRNAにポリー (A) 尾を追加するために不可欠な2つのワクチンウイルスタンパク質,VP55とVP39を特定しました. VP55は酵素として作用し,VP39はポリ (A) を結合し,尾の形成を刺激し,mRNA処理のための新しいメカニズムを明らかにします.
科学分野:
- ウイルス学 ウイルス学 ウイルス学
- 分子生物学は分子生物学である.
- 遺伝子発現の表現について
背景:
- ユカリオットmRNAは,典型的には,ポストトランスクリプションで追加された3'ポリ (A) 尾を特徴としています.
- 3'ポリ (A) 尾の形成の正確なメカニズムは完全に理解されていません.
研究 の 目的:
- 3'ポリ (A) 尾の形成のメカニズムを調査する.
- ワクチンウイルスにおけるポリアデニレーションに責任を負うウイルスタンパク質を特定し,特徴づけること.
主な方法:
- ワクチンウイルスポリペプチドVP55およびVP39の特定と浄化.
- 精製されたタンパク質と抗体を用いてポリアデニル活性測定.
- タンパク質の相互作用とポリ (A) 結合特性に関する分析.
主要な成果:
- プライマーに依存するポリアデニレーション活動は,VP55-VP39ヘテロジマーとのみ関連していました.
- ポリア) ポリメラーゼの活性性はVP55に存在し,VP39は長いポリア) 分子の合成と自由ポリア) の結合に必要であった.
- 配列データベースでVP55またはVP39の同類体は見つかりませんでした.
結論:
- ポリ・ア・テイル形成には,触媒性ポリペプチド (VP55) と解離性ポリ・ア・結合刺激因子 (VP39) が含まれる.
- これらのウイルスタンパク質は,既知のプロカリオットまたは真核酵素とは異なる,新しい種類のポリアデニレーション因子を表しています.
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