サイクロフィリンAのTRIM5への逆転移は,フクロウ猿のHIV-1に対する抵抗性を説明する
David M Sayah1, Elena Sokolskaja, Lionel Berthoux
1Department of Microbiology, Columbia University, College of Physicians and Surgeons, 701 West 168th Street, HHSC 1502 New York, New York 10032, USA.
Nature
|July 10, 2004
まとめ
オオカミ類は,融合タンパク質であるTRIMCypを介してヒト免疫不全ウイルス1型 (HIV-1) を抑制する. この抗ウイルスTRIMCyp遺伝子は,LINE-1レトロトランポゾンから発生し,TRIM5遺伝子にサイクロフィリンA (CypA) DNAを挿入した.
科学分野:
- ウイルス学 ウイルス学 ウイルス学
- 遺伝学 遺伝学とは
- 進化生物学の進化生物学について
背景:
- オールド・ワールドの霊長類はTRIM5-alphaを持ち,ヒト免疫不全ウイルス1型 (HIV-1) の侵入後を抑制する.
- ウイルスカプシドに結合するサイクロフィリンA (CypA) は,HIV-1をヒト細胞の制限から保護する.
- オオカミ類は,新世界霊長類の中で,HIV-1のエントリー後の制限を示すためにユニークです.
研究 の 目的:
- 猫のHIV-1の侵入後の制限の背後にあるメカニズムを調査する.
- この抗ウイルス活性に起因する特定の遺伝的要因を特定する.
- この霊長類特有の防御の進化的起源を理解するために.
主な方法:
- RNA干渉 (RNAi) は,フクロウ猿サイクロフィリンA (CypA) を打倒するために使用されました.
- 治療した細胞にCypAタンパク質を再導入した.
- 追加のRNAi標的のスクリーニングにより,TRIMCyp.が特定されました.
- 遺伝子移植の実験は,ヒトとネズミの細胞を用いて行われました.
主要な成果:
- オオカミ猿のCypAのノックダウンは,抗HIV-1活性低下と相関していましたが,再導入はそれを回復させませんでした.
- TRIMCyp,TRIM5-CypA融合タンパク質は,入国後の制限の要因として特定されました.
- TRIMCypは,ヒトとネズミの細胞に移転すると,HIV-1の制限を与えました.
- TRIMCyp遺伝子は,LINE-1のレトロトランポゾン媒介によるCypAcDNAのTRIM5ロカスへの挿入から発生した可能性が高い.
結論:
- TRIMCypは,フクロウ猿のHIV-1入植後の制限の主要な媒介である.
- このキメア遺伝子は,脊椎動物におけるエクソンシャッフリングを促進するレトロトランポゾンを持つ新しい進化的メカニズムを表しています.
- TRIMCypの異なる種におけるHIV-1感染をブロックする能力は,その強力な抗ウイルス機能を強調しています.
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