リケチアSca4は,ビンシュリン媒介の細胞間緊張を減らし,拡散を促進する
Rebecca L Lamason1, Effie Bastounis2, Natasha M Kafai1
1Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA.
Cell
|October 22, 2016
まとめ
斑点性熱群のリケチアは 他の細菌と違って 広がります Rickettsia parkeriは,Sca4エフェクターを含む新しいメカニズムを使用して,細胞の緊張を軽減し,細胞から細胞への移動を促進します.
科学分野:
- 微生物学
- 細胞生物学
- 病原体と宿主との相互作用
背景:
- 斑点性熱群 (SFG) のリケチアは血管細胞を感染させるヒトの病原体である.
- バクテリアの拡散は,しばしば細胞間拡散のためのアクチンベースの運動性に依存します.
- SFGリケチアの広がりは突起形成,飲み込み,真空の脱出を含みます.
研究 の 目的:
- SFG rickettsiae,特にRickettsia parkeriが利用する細胞間拡散のメカニズムを調査する.
- SFGリケチアの拡散に関与する細菌の要因を特定する.
- Rickettsia parkeriが宿主細胞のプロセスを操作して組織に広がる方法を明らかにする.
主な方法:
- トランポゾン変異は,主要な細菌エフェクターを特定するために使用されました.
- 相互作用の研究は,タンパク質とタンパク質の相互作用 (Sca4,ビンキュリン,α-カテニン) をマッピングするために行われました.
- トラクションと単層ストレス顕微鏡を用いて宿主細胞のメカニズムを分析した.
主要な成果:
- Rickettsia parkeriは通常,細胞拡散時にアクチンの尾を欠いている.
- 分泌されるエフェクターSca4は,ビンキュリンと相互作用し,ビンキュリン-α-キャテニンの結合を妨害することによって,突起の飲み込みを促進する.
- Sca4は,細胞間結合におけるビンキュリン依存メカニカル伝導を減少させ,細胞間緊張を低下させます.
結論:
- SFGリケチアはリケチア・パークリのように,アクチンベースの運動性に依存しないユニークな拡散戦略を使用します.
- エフェクターSca4は,宿主細胞間の緊張を軽減することによって,拡散を促進する上で重要な役割を果たします.
- このメカニズムは,病原体の拡散のために宿主細胞骨格の力を操作する新しいアプローチを表しています.
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