Inclusion Membrane Growth and Composition Are Altered by Overexpression of Specific Inclusion Membrane Proteins in Chlamydia trachomatis L2.
Inclusion Membrane Growth and Composition Are Altered by Overexpression of Specific Inclusion Membrane Proteins in Chlamydia trachomatis L2.
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DOI：
10.1128/iai.00094-21
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发表时间：
2021-06-16
影响因子：
3.1
通讯作者：
Rucks EA
中科院分区：
文献类型：
--
作者：
Olson-Wood MG;Jorgenson LM;Ouellette SP;Rucks EA
沙眼衣原体是细菌性性传播感染的主要原因。这种专性细胞内细菌在称为包涵体的膜结合空泡内发育，包涵体将衣原体与宿主细胞质隔离。宿主-病原体在这个界面的相互作用介导的衣原体包涵体膜蛋白（Incs）。然而，大多数Inc的具体功能特征很差。我们实验室以前的工作表明，在C.沙眼衣原体L2对包涵体扩增和子代产生产生有负面影响。我们推测，一些Incs功能的结构和组织的包涵体膜和这些Incs的过表达将改变内源性Incs的包涵体膜内的组合物。因此，包涵体生物发生和衣原体发育受到负面影响。为了研究这个问题，C。用编码IncF-、CT 813-或CT 226-FLAG的诱导型表达质粒转化沙眼衣原体L2。IncF-FLAG或CT 813-FLAG的过表达，而不是CT 226-FLAG，改变衣原体的发展，表现为较小的夹杂物，较少的后代，和质粒丢失增加。CT 813-FLAG的过表达降低了包涵体膜中内源性因斯和IncG的可检测水平。值得注意的是，在CT 813过表达后，分选连接蛋白-6（因斯的真核蛋白结合伴侣）的募集也减少。衣原体微生物的基因表达研究和超微结构分析表明，当CT 813-FLAG过表达时，衣原体发育发生改变。总之，这些数据表明，破坏特定Inc的表达改变了包涵体膜内Inc的组成和相关宿主细胞蛋白的募集，这对C.沙眼发育
Chlamydia trachomatis is the leading cause of bacterial sexually transmitted infections. This obligate intracellular bacterium develops within a membrane-bound vacuole called an inclusion, which sequesters the chlamydiae from the host cytoplasm. Host-pathogen interactions at this interface are mediated by chlamydial inclusion membrane proteins (Incs). However, the specific functions of most Incs are poorly characterized. Previous work from our laboratories indicated that expressing an IncF fusion protein at high levels in C. trachomatis L2 negatively impacted inclusion expansion and progeny production. We hypothesize that some Incs function in the structure and organization of the inclusion membrane and that overexpression of those Incs will alter the composition of endogenous Incs within the inclusion membrane. Consequently, inclusion biogenesis and chlamydial development are negatively impacted. To investigate this, C. trachomatis L2 was transformed with inducible expression plasmids encoding IncF-, CT813-, or CT226-FLAG. Overexpression of IncF-FLAG or CT813-FLAG, but not CT226-FLAG, altered chlamydial development, as demonstrated by smaller inclusions, fewer progeny, and increased plasmid loss. The overexpression of CT813-FLAG reduced the detectable levels of endogenous IncE and IncG in the inclusion membrane. Notably, recruitment of sorting nexin-6, a eukaryotic protein binding partner of IncE, was also reduced after CT813 overexpression. Gene expression studies and ultrastructural analysis of chlamydial organisms demonstrated that chlamydial development was altered when CT813-FLAG was overexpressed. Overall, these data indicate that disrupting the expression of specific Incs changed the composition of Incs within the inclusion membrane and the recruitment of associated host cell proteins, which negatively impacted C. trachomatis development.