サルモネラは,マノース-6-リン酸受容体とリソソーム機能の逆行密輸を抑制する
Kieran McGourty1, Teresa L Thurston, Sophie A Matthews
1Section of Microbiology, Centre for Molecular Microbiology and Infection, Imperial College London, Armstrong Road, London SW7 2AZ, UK.
まとめ
サルモネラ・エンテリカは,エフェクターSifAを使用して,マノース-6-リン酸受容体 (MPR) の密輸を妨害することによって,宿主細胞リゾソーム機能を妨害します. この細菌戦略は,ライソソームの活性性を低下させることでサルモネラ菌の増殖を促進します.
科学分野:
- 微生物学 微生物学とは
- 細胞生物学 細胞生物学
- 病原体と宿主の相互作用
背景:
- サルモネラ・エンテリカは,真空中に複製する細胞内病原体です.
- サルモネラバキュオルは,リゾソーマ特性を示すが,水解酵素の含有量が減少している.
- マノース-6-リン酸受容体 (MPR) は,リソソーム酵素輸送に不可欠です.
研究 の 目的:
- サルモネラエフェクターSifAが宿主細胞溶解体機能に影響を与えるメカニズムを調査する.
- MPRの密輸におけるSifA-SKIP/PLEKHM2の相互作用の役割を決定する.
- サルモネラ菌が宿主細胞の輸送経路を複製のために操作する方法を解明する.
主な方法:
- サルモネラエフェクターSifAと宿主細胞タンパク質SKIP/PLEKHM2.0の相互作用を調査しました.
- Rab9依存のMPRの逆行トラフィックに対するSifAの効果を分析した.
- リソソーム活性が調節された宿主細胞におけるサルモネラ増殖を評価した.
主要な成果:
- SifAはSKIP/PLEKHM2と結合し,Rab9依存のMPR逆行トラフィックを逆転させ,ライソソーム機能を弱体化させます.
- SifAは,感染した細胞でSKIPとRab9と安定した複合体を形成し,Rab9.9を隔離します.
- サルモネラ菌の成長は,リゾソーム活性が低下した細胞では増加し,活性性が高い細胞では減少します.
結論:
- サルモネラバキュオールは宿主細胞リソソームと融合し,その力はSifAによって低下する.
- SifAによるMPRの密輸の妨害は,サルモネラ菌の病原性の重要なメカニズムである.
- ホスト細胞の逆行輸送をターゲットにすることは,細胞内複製のための保存された細菌の戦略です.
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