CagY天线投影在Helicobacter pylori的IV型Cag分泌系统活动中的作用
Sirena C Tran1, Mark S McClain2,3, Timothy L Cover1,2,3,4
1Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center , Nashville, Tennessee, USA.
Infection and immunity
|August 28, 2023
概括
杆菌的CagY天线区域对于IV型分泌系统 (T4SS) 功能至关重要,包括CagA输送. 改变其循环的长度会调节T4SS活动,影响胃病的发展.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 病变的发生和发病.
背景情况:
- 具有CAG病原性岛 (PAI) 的Helicobacter pylori菌株与胃腺癌和胃潰瘍疾病有关.
- 卡格PAI编码了卡格A效应蛋白和IV型分泌系统 (卡格T4SS),这对于将基质输送到宿主细胞至关重要.
- Cag T4SS外膜核心复合体 (OMCC) 具有来自CagY (VirB10 ortholog) 的天线投影 (AP),预计将跨越外膜.
研究的目的:
- 调查CagY天线区域在Cag T4SS OMCC组装和功能中的作用.
- 为了确定CagY AP循环的修改如何影响T4SS活动.
主要方法:
- 在CagY AP区域中构建和分析H. pylori突变菌株的缺失或修改.
- 在AGS胃上皮细胞中评估OMCC组合,CagA转位和IL-8诱导.
主要成果:
- 一个缺乏整个CagY AP (∆AP) 的突变者组装了一个OMCC,但缺乏T4SS活动.
- 在CagY AP循环中具有Gly-Ser替代物的突变体保留了T4SS活性.
- 缩短的CagY AP循环导致CagA转位缺陷并减少IL-8的诱导.
结论:
- CagY AP区域对于Cag T4SS活动至关重要.
- CagY AP非结构循环的长度可以调节Cag T4SS的功能,从而影响细菌的发病性.
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