リステリアの転写の景観は,サプロフィティズムから毒性まで
Alejandro Toledo-Arana1, Olivier Dussurget, Georgios Nikitas
1Institut Pasteur, Unité des Interactions Bactéries-Cellules, F-75015 Paris, France.
Nature
|May 19, 2009
まとめ
この研究は,リステリア・モノサイトゲネスが,環境の生存から感染を引き起こすことへの移行を,その全ゲノム転写を分析することによって明らかにしています. バクテリアの病原性およびウイルス性遺伝子発現に不可欠な新しいRNA調節体を明らかにします.
科学分野:
- 微生物学 微生物学とは
- ゲノミクスゲノミクスとは
- 分子生物学は分子生物学である.
背景:
- Listeria monocytogenesは,重度の食品感染症を引き起こす環境細菌です.
- サプロフィットから病原体への移行は十分に理解されていません.
- パトジェネシスを研究するためのモデル生物としてますます使用されています.
研究 の 目的:
- Listeria monocytogenesのトランスクリプション環境を包括的に分析する.
- 病原性状態への移行を規制する新しい規制メカニズムを特定する.
- 完全なオペロン構造と多様なRNA種をマッピングするために.
主な方法:
- 全ゲノムタイリング配列は,野生型および変異性細菌からのRNAを分析するために使用されました.
- バクテリアの転写は,in vitro,ex vivo,およびin vivo条件で研究されました.
- Listeria innocuaとの比較分析が行われました.
主要な成果:
- 完全なリステリアオペロンマップが作成され,広範囲のRNA多様性が明らかになりました.
- 50以上の小さなRNA,アンチセンセスのRNA,および重複する翻訳されていない領域が特定されました.
- SigBとPrfAは,異なる宿主環境における毒性遺伝子の重要な調節体として確認されました.
- ウイルス性遺伝子発現と相関する新しいノンコーディングRNAが発見されました.
結論:
- Listeria monocytogenesは,宿主感染中に重要な転写再プログラムを受けます.
- さまざまなRNA種を含むこれまで未知の規制メカニズムは,細菌の病原性を制御する.
- 特定の非コーディングRNAは,ウイルス性に関連しており,非病原性親類には存在しない.
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