サイクルGMP-AMPシグナリングは,細菌をウイルス感染から保護します
Daniel Cohen1, Sarah Melamed1, Adi Millman1
1Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel.
Nature
|September 19, 2019
まとめ
細菌は,ファグ感染に対する防御として,サイクルGMP-AMP合成酶 (cGAS) を含むサイクルGMP-AMP (cGAMP) シグナル伝達を利用する. この古代の微生物系は ウイルスの繁殖を防ぐために 細胞死を誘発し 動物の同様の抗ウイルス経路を先導します
科学分野:
- 微生物学
- 免疫学
- 分子生物学
背景:
- サイクルGMP- AMP合成酵素 (cGAS) - STING経路は,動物における先天的免疫において決定的であり,細胞細胞DNAを感知して抗ウイルス反応を開始する.
- 周期的なGMP-AMP (cGAMP) 信号伝達が細菌で観察されており,いくつかの研究により,細菌膜を分解するフォスホリパゼを活性化することが示されている.
研究 の 目的:
- バクテリアにおけるcGAMPシグナル伝達の生物学的な役割を調査する.
- cGAMPを含む細菌の抗菌防御システムの構成要素とメカニズムを特定する.
主な方法:
- バクテリアのcGAS,フォスフォリファーゼ,および真核生物のような酵素をコードする4遺伝子オペロンの遺伝子分析.
- 特定されたオペロンによるファグ耐性を評価する.
- ファグ感染時にフォスフォリファースの活性と細胞死を引き起こすcGAMPの役割を調査する.
主要な成果:
- バクテリアのcGASおよび関連する酵素を含む4遺伝子オペロンを含む一般的な細菌の抗菌防御システムが特定されました.
- このシステムは,感染時にcGAMPを生成し,膜の整合性を損なうフォスフォリファースを活性化させ,細胞死を招きます.
- このシステムの異なるバージョンは10パーセント以上のプロカリオートゲノムに存在し,異なるエフェクターを使用する変種もファグの保護を提供します.
結論:
- バクテリアのcGAMP-cGASシステムは,ファージに対する古くから広範囲にわたる防御メカニズムを表しています.
- ユカリオットのcGAS-STING抗ウイルス経路は,おそらくこれらの原始的な微生物の防御戦略から進化した.
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