バクテリアのcGASはウイルスRNAを感知して免疫を起こす

Dalton V Banh^1,2, Cameron G Roberts¹, Adrian Morales-Amador³

¹Laboratory of Bacteriology, The Rockefeller University, New York, NY, USA.

|November 15, 2023

まとめ

循環性オリゴヌクレオチドベースの抗菌体シグナル伝達システム (CBASS) は,バクテリアの防御を活性化するために,ファグでコードされたRNA (cabRNA) を使用する. 脱出ファージは,この免疫反応を回避するcabRNA変種を進化させる.

科学分野:

微生物学
分子生物学
免疫学

背景:

周期性オリゴヌクレオチドベースの抗菌体シグナリングシステム (CBASS) は,ファグ感染に対するプロカリオットの防御メカニズムである.
細菌サイクラスがファグ感染を検出する正確なメカニズムは不明である.

研究の目的:

バクテリアのサイクラスがファグの感染を認識する方法を解明する.
CBASSの活性化に関与する分子成分を特定する

主な方法:

菌素由来RNA分子 (cabRNA) の識別と特徴付け
cabRNAとCdnE03サイクラゼの相互作用を評価する生化学的測定法
ファージ脱出変異体とその対応するcabRNA変異体の分析

主要な成果:

スタフィロコクスのファージは,ターミナーゼサブユニット遺伝子からCBASS活性化細菌菌RNA (cabRNA) を生成する.
cabRNAはCdnE03サイクラゼと結合し,cGAMPの合成とCBASSの活性化を促進する.
ファージ脱出ミュータントは,CdnE03を活性化できない変異したcabRNA形式を持っています.

結論:

cabRNAはバクテリアのCBASS免疫を活性化する重要なファグ由来信号です.
先天的な抗ウイルス防御を活性化させるための保存されたメカニズムが存在し,これは原生生物のCBASSと哺乳類のインターフェロン反応の両方で見られるように,サイクラゼへのRNA結合を含む.

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