在Vibrio parahaemolyticus中对宿主细胞接触依赖的T3SS基因表达的调控机制
Sarunporn Tandhavanant1,2, Hiroyuki Terashima1,3, Hirotaka Hiyoshi1
1Department of Bacteriology, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan.
mSystems
|June 17, 2025
概括
维布里奥帕拉海莫利蒂克斯 (Vibrio parahaemolyticus) 使用第三型分泌系统2 (T3SS2) 来感知宿主细胞接触. 这会触发VtrN的分泌,这是一种抑制毒性基因表达的蛋白质,增强细菌感染策略.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 细菌病原体的产生
背景情况:
- 病原性细菌适应基因表达以适应它们的环境感染.
- 宿主细胞接触是一个关键的环境暗示,触发细菌毒性基因调节.
- 第三类分泌系统 (T3SS) 是许多细菌病原体中必不可少的毒性因素,需要精确的调节.
研究的目的:
- 为了阐明病毒性基因表达的宿主细胞接触依赖的调节机制在Vibrio parahaemolyticus.
- 识别参与感知宿主细胞接触和调节毒性因子生产的特定组件.
- 了解Vibrio parahaemolyticus如何在与宿主细胞相互作用时适应其毒性策略.
主要方法:
- 对T3SS2守门员突变的转录组分析.
- 进行比较蛋白质组分析以确定新型T3SS2基质.
- 基因删除和相互作用研究以描述VtrN的功能.
- 在模仿宿主细胞接触的条件下培养细菌.
主要成果:
- 维布里奥甲血解菌利用T3SS2通过细胞内K+水平感知宿主细胞接触,切换分泌基质.
- 一种新的T3SS2基质VtrN被确定为Vp-PAI (病毒性基因集群) 转录的负调节者.
- 在宿主细胞接触时促进VtrN分泌,其删除可提高Vp-PAI表达的调节.
- VtrN与转录因子VtrB直接相互作用,抑制Vp-PAI基因活性.
结论:
- 维亚血解菌 (Vibrio parahaemolyticus) 采用一种复杂的T3SS2介导机制,在宿主细胞接触时对病毒性基因表达进行上调.
- 所分泌的蛋白质VtrN起到关键的抑制作用,将宿主细胞传感与病毒性基因转录的控制联系起来.
- 这种适应性策略允许V. parahaemolyticus在宿主感染期间优化其毒性因子的产生,为细菌病原性提供了洞察力.
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