The Effector Cig57 Hijacks FCHO-Mediated Vesicular Trafficking to Facilitate Intracellular Replication of Coxiella burnetii.
The Effector Cig57 Hijacks FCHO-Mediated Vesicular Trafficking to Facilitate Intracellular Replication of Coxiella burnetii.
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DOI：
10.1371/journal.ppat.1006101
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发表时间：
2016-12
期刊：
影响因子：
6.7
通讯作者：
Newton HJ
中科院分区：
文献类型：
--
作者：
Latomanski EA;Newton P;Khoo CA;Newton HJ
贝氏柯克斯体是一种细胞内细菌病原体，感染肺泡巨噬细胞并在独特的溶酶体衍生的空泡内复制。当柯克斯体被运输到宿主细胞溶酶体时，必需的Dot/Icm IV型分泌系统被激活，允许超过130种细菌效应蛋白易位到宿主细胞质中。据信这一组效应物操纵宿主细胞功能以促进含柯克斯体的空泡（CCV）生物发生和细菌复制。转座子诱变已经证明，Dot/Icm效应子C57是CCV发展和柯克斯体细胞内复制所必需的。在这里，我们证明了一个作用，通过其与FCHO2，一个辅助蛋白的网格蛋白包被的坑在颠覆网格蛋白介导的交通。酵母双杂交筛选鉴定FCHO 2作为BMP57的结合伴侣，并且在感染期间使用免疫沉淀实验证实了这种相互作用。FCHO2和FCHO57之间的相互作用依赖于由FCHO57编码的三个内吞分选基序之一。重要的是，互补分析表明，这种内吞分选基序是必需的完整功能的p57。与cig57破坏的柯克斯体中的细胞内生长缺陷一致，FCHO 2或网格蛋白（CLTC）的siRNA基因沉默抑制柯克斯体生长和CCV生物发生。网格蛋白被募集到复制型CCV中，其募集方式依赖于CCV 57和FCHO 2之间的相互作用。FCHO2敲除细胞系的建立证实了该蛋白对于CCV扩增、柯克斯体的细胞内复制和网格蛋白向CCV的募集的重要性。总的来说，这些结果揭示了EST57是一个重要的毒力因子，通过与FCHO 2的相互作用，协同选择网格蛋白介导的运输，以促进融合柯克斯体复制空泡的生物发生，并使这种人类病原体的细胞内成功。人类Q热是由细胞内细菌贝氏柯克斯体引起的。人细胞的成功感染依赖于Dot/Icm分泌系统和效应蛋白易位到宿主细胞胞质溶胶中。许多柯克斯体效应蛋白的功能，以及它们对细菌生长和宿主操纵的贡献仍然未知。我们发现，一个独特的效应，EST57，在操纵宿主细胞网格蛋白介导的贩运有重要的作用。特别是，FCH02，一种参与网格蛋白包被的囊泡形成的蛋白质，以依赖于基于酪氨酸的内吞分选基序的方式结合FCH05。通过参与网格蛋白途径中的蛋白质，E157促进柯克斯体复制泡的扩张，并使病原体能够大量复制。因此，我们确定了宿主过程和病原体成功所需的关键毒力蛋白之间的关系。
Coxiella burnetii is an intracellular bacterial pathogen that infects alveolar macrophages and replicates within a unique lysosome-derived vacuole. When Coxiella is trafficked to a host cell lysosome the essential Dot/Icm type IV secretion system is activated allowing over 130 bacterial effector proteins to be translocated into the host cytosol. This cohort of effectors is believed to manipulate host cell functions to facilitate Coxiella-containing vacuole (CCV) biogenesis and bacterial replication. Transposon mutagenesis has demonstrated that the Dot/Icm effector Cig57 is required for CCV development and intracellular replication of Coxiella. Here, we demonstrate a role for Cig57 in subverting clathrin-mediated traffic through its interaction with FCHO2, an accessory protein of clathrin coated pits. A yeast two-hybrid screen identified FCHO2 as a binding partner of Cig57 and this interaction was confirmed during infection using immunoprecipitation experiments. The interaction between Cig57 and FCHO2 is dependent on one of three endocytic sorting motif encoded by Cig57. Importantly, complementation analysis demonstrated that this endocytic sorting motif is required for full function of Cig57. Consistent with the intracellular growth defect in cig57-disrupted Coxiella, siRNA gene silencing of FCHO2 or clathrin (CLTC) inhibits Coxiella growth and CCV biogenesis. Clathrin is recruited to the replicative CCV in a manner that is dependent on the interaction between Cig57 and FCHO2. Creation of an FCHO2 knockout cell line confirmed the importance of this protein for CCV expansion, intracellular replication of Coxiella and clathrin recruitment to the CCV. Collectively, these results reveal Cig57 to be a significant virulence factor that co-opts clathrin-mediated trafficking, via interaction with FCHO2, to facilitate the biogenesis of the fusogenic Coxiella replicative vacuole and enable intracellular success of this human pathogen. Human Q fever is caused by the intracellular bacterium Coxiella burnetii. Successful infection of human cells relies on a Dot/Icm secretion system and the translocation of effector proteins into the host cell cytosol. The functions of many Coxiella effector proteins, and their contribution to bacterial growth and host manipulation, remain unknown. We show that a unique effector, Cig57, has an important role in manipulation of host cellular clathrin-mediated trafficking. In particular, Cig57 binds FCHO2, a protein involved in formation of clathrin-coated vesicles, in a manner that is dependent on a tyrosine-based endocytic sorting motif. Through engaging proteins in the clathrin pathway, Cig57 facilitates expansion of the Coxiella replicative vacuole and enables the pathogen to replicate to large numbers. Thus, we identify a relationship between a host process and a key virulence protein that are required for pathogen success.
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影响因子：
6.7
作者：
Carey KL;Newton HJ;Lührmann A;Roy CR
通讯作者：
Roy CR
影响因子：
6.4
作者：
Beare PA;Gilk SD;Larson CL;Hill J;Stead CM;Omsland A;Cockrell DC;Howe D;Voth DE;Heinzen RA
通讯作者：
Heinzen RA
影响因子：
6.4
作者：
McDonough JA;Newton HJ;Klum S;Swiss R;Agaisse H;Roy CR
通讯作者：
Roy CR
影响因子：
3.7
作者：
Newton HJ;McDonough JA;Roy CR
通讯作者：
Roy CR
DOI：
10.1073/pnas.1309195110
发表时间：
2013-12-03
影响因子：
11.1
作者：
Larson, Charles L.;Beare, Paul A.;Heinzen, Robert A.
通讯作者：
Heinzen, Robert A.