病原体タンパク質 EspF(U) は,真似と多価性を用いてアクチンポリメリゼーションをハイジャックする.
Nathan A Sallee1, Gonzalo M Rivera, John E Dueber
1Graduate Program in Chemistry and Chemical Biology, University of California, San Francisco, 600 16th Street, San Francisco, California 94158, USA.
Nature
|July 25, 2008
まとめ
エントロヘモラジックなEscherichia coliはEspF (U) タンパク質を使用して宿主細胞のアクチン足場形成を誘発します. このタンパク質は,CDC42ではなく,内部のN-WASP要素を独特に模倣して,細菌の結合のためのアクチンポリメリゼーションを活性化します.
科学分野:
- 微生物学 微生物学とは
- 細胞生物学 細胞生物学
- バイオケミストリー バイオケミストリー
背景:
- 腸出血性Escherichia coli (EHEC) は,アクチンの足場を使って腸に付着します.
- バクテリアのタンパク質EspF(U) (TccP) を宿主細胞に注入すると,アクチンの足場を形成する.
- EspF(U) は,ウィスコット・オルドリッヒ症候群タンパク質 (WASP) 家族のアクチンヌクレエーターを活性化させ,通常はCDCによって規制されます42.
研究 の 目的:
- EspF (U) がN-WASPを活性化するメカニズムを解明する.
- N-WASPの相互作用に起因する特定のEspF (U) モチーフを特定する.
- EspF(U) が宿主細胞の機械を細菌の粘着のためにどのように利用するかを理解するために.
主な方法:
- EspF ((U) の構造分析が繰り返される.
- EspF ((U)) 内のN-WASP結合モチーフの識別.
- アクチンポリメリゼーションとN-WASP活性化を測定するための生化学分析.
主要な成果:
- EspF (U) リピート内の17アミノ酸モチーフは,N-WASP結合に十分である.
- EspF (U) は,N-WASPの自己抑制要素を模倣し,自然な活性化剤であるCDC42.4を模倣している.
- 複数のEspF(U) リピートは,N-WASPの活性化を調整することによって,アクチンポリメリゼーションの効能を高めます.
結論:
- EHEC EspF ((U) は,その自己抑制状態を妨害することによってN-WASPを活性化させ,病原体と宿主の相互作用の新しいメカニズムを提供します.
- 病原体は,単純で繰り返される自己抑制的断片を使用して強力なアクチンポリメリゼーションマシンを設計しました.
- このメカニズムは,特定の細胞プロセスの選択的活性化を可能にし,細菌のコロニー化を促進します.
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