HIV-1 U3領域によって課された核翻訳ブロックは,Tat-TAR相互作用によって緩和されます
M Braddock1, A M Thorburn, A Chambers
1Virus Molecular Biology Group, Department of Biochemistry, Oxford, United Kingdom.
Cell
|September 21, 1990
まとめ
ヒト免疫不全ウイルス1型 (HIV-1) Tatタンパク質は,ウイルスの複製に不可欠です. TatはウイルスRNAの発現を高めますが,それは細胞核内でのみであり,HIV-1 LTRから発現の可能性を救出します.
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
- 遺伝子発現の表現について
背景:
- HIV-1の複製は,ウイルスのタットタンパク質に依存しています.
- Tatは,ウイルスのLTRとmRNAのTAR要素と相互作用する.
- TatとTARRNAの核の局所化は,Tatの機能にとって極めて重要です.
研究 の 目的:
- TAT媒介の増強におけるTARループの役割を調査する.
- HIV-1 U3領域がmRNA発現能力に影響するかどうかを判断する.
- Tat-TARシステムがHIV-1RNA発現にどのように影響するかを理解する.
主な方法:
- TARループの突然変異.
- HIV-1 LTRおよびCMV-IEプロモーターからのRNA発現の比較.
- RNAトランスレーション効率の評価.
主要な成果:
- TARループのわずかな変更により,タットの核増強効果は排除されました.
- HIV-1 U3領域は,合成されたmRNAの発現を無能にしました.
- CMV-IEプロモーターから生成された同一のRNAが効率的に翻訳されました.
結論:
- Tat-TAR相互作用は,HIV-1遺伝子発現の核増強に極めて重要です.
- HIV-1 LTR,特にU3領域には,mRNA発現を阻害する要素が含まれています.
- Tat-TARシステムは,HIV-1 LTR誘導RNA発現の重要な救済メカニズムとして機能する.
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