アデノウイルスE1Aタンパク質は,E2F転写因子を含む異体複合体を解離することができる:E1Aトランス活性化のための新しいメカニズム
S Bagchi1, P Raychaudhuri, J R Nevins
1Howard Hughes Medical Institute, Duke University Medical Center, Durham, North Carolina 27710.
Cell
|August 24, 1990
まとめ
アデノウイルスE1Aタンパク質は,細胞複合体から転写因子E2Fを放出する. これにより,E4タンパク質がE2Fと相互作用し,安定したDNA結合を促進し,転写を刺激します.
科学分野:
- 分子生物学は分子生物学である.
- ウイルス学 ウイルス学 ウイルス学
- 遺伝子規制 遺伝子規制
背景:
- アデノウイルス感染症には,E2F転写因子が関与し,プロモーターはE4遺伝子産物を持つ複合体を通して安定的に結合します.
- 細胞因子は,感染していない細胞で自然にE2Fと関連し,潜在的にその活動を調節します.
研究 の 目的:
- E2F転写因子複合体の形成を調節するアデノウイルスE1Aタンパク質の役割を調査する.
- E1AがE2Fの相互作用と,その後の転写活性化に影響を与えるメカニズムを解明する.
主な方法:
- バイオケミカルアッセイを用いた細胞抽出物におけるタンパク質-タンパク質相互作用の分析.
- E2F複合体の解離に必要なE1Aタンパク質の機能ドメインの調査.
主要な成果:
- アデノウイルスE1Aタンパク質は,感染していない細胞のE2Fから細胞因子を分離し,フリーE2Fを放出します.
- E1Aの解離活動は保存ドメイン2に依存するが,保存ドメイン3には依存しない.
- 分離されたE2Fは,E4タンパク質と容易に相互作用し,E2プロモーターで安定した複合体を形成し,転写を強化します.
結論:
- アデノウイルスE1Aタンパク質は,転写因子複合体を解離する新しい機能を持っています.
- このE1Aによる解離は,新しいタンパク質の相互作用を促進し,ウイルス感染中に転写特異性を変化させます.
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