HIV-1の構造的遺伝子発現には,Revトランスアクティベーターが,そのRNA標的配列に結合することが必要である
M H Malim1, L S Tiley, D F McCarn
1Howard Hughes Medical Institute, Department of Microbiology and Immunology, Duke University Medical Center, Durham, North Carolina 27710.
Cell
|February 23, 1990
まとめ
ヒト免疫不全ウイルス1型Revトランス活性化剤は,ウイルスのタンパク質発現に不可欠な特定のRNA配列 (RRE) を結合します. この結合は,小さなRREサブドメインとRev.のアルギニン豊富なモチーフによって媒介されます.
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
- RNA 生物学 RNA 生物学
背景:
- ヒト免疫不全ウイルス1型 (HIV-1) の構造タンパク質発現は,Revトランス活性化剤とそのRNA標的であるRev応答要素 (RRE) に依存する.
- RREはHIV-1遺伝子の保存された領域に位置し,安定したRNA幹ループ構造を形成する.
研究 の 目的:
- Rev結合と生物学的活性にとって重要な特定のRREサブドメインを特定する.
- RevトランスアクティベーターとRREの相互作用を特徴づける.
主な方法:
- RREを改変するためのサイト指向型変異.
- Rev-RRE結合を評価するためのゲル遅延測定法.
主要な成果:
- RREの小さなサブドメインである"stem-loop II"は,生物学的活動に不可欠であると特定されました.
- ステム・ループIIは,RevがRREと結合するために必要で十分であることが判明しました.
- Revトランスアクティベーターは,配列特異的なRNA結合タンパク質であると確認されました.
結論:
- HIV-1 Revトランスアクティベーターは,RRE内の特定のRNA幹ループIIサブドメインと相互作用する.
- Revは,アルギニンに富んだ結合モチーフを特徴とする,シーケンス固有のRNA結合タンパク質の新種のクラスであると提案されています.
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