感染巨噬细胞的双重蛋白质组学揭示了参与弗朗西斯菌细胞内生命周期和通过细胞吞噬作用细胞间传播的细菌和宿主因子。
Dual proteomics of infected macrophages reveal bacterial and host players involved in the Francisella intracellular life cycle and cell to cell dissemination by merocytophagy.
机构信息
Université Paris CitéINSERM UMR-S1151, CNRS UMR-S8253Institut Necker Enfants Malades, 156-160 rue de Vaugirard, 75015, Paris, France.
INSERM U1151-CNRS UMR 8253, Team 7: Pathogénie des Infections Systémiques, 75015, Paris, France.
出版信息
Sci Rep. 2024 Apr 2;14(1):7797. doi: 10.1038/s41598-024-58261-x.
Bacterial pathogens adapt and replicate within host cells, while host cells develop mechanisms to eliminate them. Using a dual proteomic approach, we characterized the intra-macrophage proteome of the facultative intracellular pathogen, Francisella novicida. More than 900 Francisella proteins were identified in infected macrophages after a 10-h infection. Biotin biosynthesis-related proteins were upregulated, emphasizing the role of biotin-associated genes in Francisella replication. Conversely, proteins encoded by the Francisella pathogenicity island (FPI) were downregulated, supporting the importance of the F. tularensis Type VI Secretion System for vacuole escape, not cytosolic replication. In the host cell, over 300 proteins showed differential expression among the 6200 identified during infection. The most upregulated host protein was cis-aconitate decarboxylase IRG1, known for itaconate production with antimicrobial properties in Francisella. Surprisingly, disrupting IRG1 expression did not impact Francisella's intracellular life cycle, suggesting redundancy with other immune proteins or inclusion in larger complexes. Over-representation analysis highlighted cell-cell contact and actin polymerization in macrophage deregulated proteins. Using flow cytometry and live cell imaging, we demonstrated that merocytophagy involves diverse cell-to-cell contacts and actin polymerization-dependent processes. These findings lay the groundwork for further exploration of merocytophagy and its molecular mechanisms in future research.Data are available via ProteomeXchange with identifier PXD035145.
细菌病原体在宿主细胞内适应和复制,而宿主细胞则发展出消除它们的机制。我们使用双重蛋白质组学方法,描述了兼性细胞内病原体弗朗西斯菌属 novicida 感染巨噬细胞后的细胞内蛋白质组。在 10 小时的感染后,感染的巨噬细胞中鉴定出超过 900 种弗朗西斯菌蛋白。生物素生物合成相关蛋白上调,强调了生物素相关基因在弗朗西斯菌复制中的作用。相反,弗朗西斯菌致病性岛 (FPI) 编码的蛋白下调,支持了 F. tularensis Type VI 分泌系统对于空泡逃逸而非细胞质复制的重要性。在宿主细胞中,在感染期间鉴定出的 6200 种蛋白中,有超过 300 种蛋白表达水平不同。上调最明显的宿主蛋白是顺乌头酸脱羧酶 IRG1,它以产生具有抗弗朗西斯菌特性的衣康酸而闻名。令人惊讶的是,破坏 IRG1 的表达并不影响弗朗西斯菌的细胞内生命周期,这表明其与其他免疫蛋白具有冗余性或包含在更大的复合物中。过度表达分析突出了巨噬细胞失调蛋白中的细胞-细胞接触和肌动蛋白聚合。通过流式细胞术和活细胞成像,我们证明了吞噬细胞包含多种细胞-细胞接触和依赖肌动蛋白聚合的过程。这些发现为未来研究中吞噬细胞吞噬作用及其分子机制的进一步探索奠定了基础。数据可通过 ProteomeXchange 以标识符 PXD035145 获得。