新種のCDK9関連C型サイクリンは,HIV-1 Tatと直接相互作用し,その高親和性,ループ特異的な結合をTAR RNAに媒介する
1Regulatory Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, California 92037-1099, USA.
Cell
|March 10, 1998
まとめ
HIV-1 Tatタンパク質は,サイクリンTを使用して,TARRNAへの結合を強化し,転写を促進します. この相互作用はウイルスの遺伝子発現に不可欠であり,ネズミの細胞におけるヒトサイクリンTによって救出され得る.
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
- バイオケミストリー バイオケミストリー
背景:
- HIV-1 Tatタンパク質は,ウイルス転写の延長に不可欠です.
- Tatは,TAR RNAの幹ループ構造に結合し,遺伝子発現を調節する.
- Tat媒介の転写強化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:
- HIV-1 Tat.と相互作用する新しい細胞因子を特定する.
- Tat媒介による転写調節におけるサイクリンTの役割を明らかにする.
- TatがTARRNAとの相互作用を強化するメカニズムを調査する.
主な方法:
- サイクリンTを分離し,特徴づけるためのタンパク質相互作用の研究.
- Tat:TAR RNAの結合親和性と特異性の分析.
- 細胞系におけるサイクリンTの過剰発現を含む機能分析.
主要な成果:
- 新しい87 kDaのサイクリンC関連タンパク質,サイクリンTが特定されました.
- Cyclin Tは,特にTatトランザクションドメインと相互作用し,CDK9.9と提携しています.
- タット-サイクリンT相互作用は,Tat:TAR RNAの結合親和性と特異性を著しく高めます.
- 人間のサイクリンTの過剰発現は,許容性のない歯類の細胞におけるTAT活性を救出する.
結論:
- HIV-1 Tatは,T-CDK9サイクリンを,TAR RNAへの協同結合を通じてRNAPIIに誘導する.
- サイクリンTは,Tat媒介による転写延長のための重要なコファクターである.
- この相互作用は,抗ウイルス療法のための潜在的な標的を代表しています.
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