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Cryo-EMは,ベタレトロウイルスインタソーム機能のための新しいオクタメリクス・インテグラーゼ構造を明らかにした
Allison Ballandras-Colas1, Monica Brown2, Nicola J Cook3
1Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute and Department of Medicine, Harvard Medical School, 450 Brookline Avenue, Boston, Massachusetts 02215, USA.
Nature
|February 19, 2016
まとめ
研究者はマウスの乳がんウイルスインタソームで予期せぬオクタメリクス・インテグラーゼ構造を発見し,レトロウイルスのDNA統合メカニズムに関する新しい洞察を明らかにし,以前のテトラメリクスモデルに挑戦しました.
科学分野:
- 構造生物学
- ウイルス学
- 分子生物学
背景:
- レトロウイルスインテグラーゼは,宿主ゲノムにウイルスのDNAを統合するのに不可欠です.
- 以前の研究では,インタソームのテトラメリック・インテグラーゼ構造が示唆された.
- 病原性種を含むオーソレトロウイルスインタソームの構造は特徴づけられていなかった.
研究 の 目的:
- マウス乳腺腫瘍ウイルス (MMTV) の構造構造を決定する.
- レトロウイルス DNA 統合におけるインテグラーゼ オリゴメリゼーションの役割を調査する.
主な方法:
- 単粒子冷凍電子顕微鏡
- X線結晶学
主要な成果:
- 予期せぬオクタメリクス・インテグラーゼ構造が,MMTVインタソームで決定された.
- オクタマーは2つのコアディマーと2つの側面ディマーで構成され,MMTVインテグラーゼ活性には側面ディマーが不可欠である.
- このオクタメリック構造は,リンク器の制約のために cis に欠けていた必要なカーボキシ末端ドメインを提供します.
結論:
- MMTVインタソームは,推定のテトラメリックモデルとは異なるオクトメリク・インテグラーゼを用いる.
- このオクタメリック構造はベタレトロウイルスとアルファレトロウイルスにとって不可欠であり,進化の限界を克服します.
- この発見は,レトロウイルスDNAの統合メカニズムに関する新しい構造的洞察を提供します.
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