アクチンのポリメリゼーションは,Listeria monocytogenesの表面にあるArp2/3タンパク質複合体によって誘発されます
M D Welch1, A Iwamatsu, T J Mitchison
1Department of Cellular and Molecular Pharmacology, University of California at San Francisco, 94143, USA. welch@cgl.ucsf.edu
Nature
|January 16, 1997
まとめ
Listeria monocytogenesは,宿主細胞のタンパク質複合体によって駆動されるアクチンポリメリゼーションを使用して自分自身を推進します. アクチン関連タンパク質 (ARP) を含むこの複合体は,アクチンアセンブリを核化し,宿主細胞内の細菌の運動性を可能にします.
科学分野:
- 細胞生物学 細胞生物学
- 微生物学 微生物学とは
- バイオケミストリー バイオケミストリー
背景:
- Listeria monocytogenesのような病原性細菌は,宿主細胞の細胞プラズマ内で,指向された動きを示す.
- バクテリアの運動性は,バクテリアの表面でのアクチンポリメリゼーションによって推進され,アクチン尾を形成します.
- このアクチンポリメリゼーションメカニズムを理解することは,細胞アクチンダイナミクスの制御に不可欠です.
研究 の 目的:
- Listeria monocytogenesが利用するアクチンポリメリゼーションのメカニズムを解明する.
- ActA依存性アクチンアセンブリに関与する宿主細胞因子を特定し,特徴づけること.
- 細菌の運動性における浄化された宿主細胞タンパク質複合体の役割を調査する.
主な方法:
- 8つのポリペプチドの宿主細胞タンパク質複合体の浄化.
- 浄化された複合体のActA依存型アクチンポリメリゼーションを開始する能力を評価する.
- 感染した組織培養細胞にArp3サブユニットを定位する.
主要な成果:
- 浄化された8ポリペプチド複合体が宿主細胞アクチンポリメリゼーション因子として特定されました.
- この複合体は,ActA依存性アクチンポリメリゼーションを開始し,アクチン尾の形成を媒介するのに十分です.
- この複合体には,Arp2とArp3のアクチン関連タンパク質 (ARP) が含まれており,Arp3はバクテリアの表面とアクチン尾部に局在する.
- Arp2/3複合体はテンプレートとして作用し,アクチンポリメリゼーションを核化する.
結論:
- 浄化されたArp2/3複合体は,Listeria monocytogenesのアクチンベースの運動性にとって不可欠である.
- Arp2/3複合体は,アクチン核形成促進因子として in vivo で機能する.
- この研究は,細菌病原体によるアクチンポリメリゼーションの調節に関する洞察を提供します.
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