线性ubiquitin机械的致病酸化导致炎症体传感器退化
Yang Yu1, Shanshan Yu2, Zhe Lu1
1Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; Medical School, University of Chinese Academy of Sciences, Beijing 101408, China.
Cell reports
|September 13, 2025
概括
结核菌的PknG激酶通过向LUBAC复合体来破坏宿主免疫力. 这种细菌蛋白质可以防止炎症酶激活,通过颠覆细胞防御机制来帮助持续感染.
科学领域:
- 免疫学 免疫学 免疫学
- 微生物学 微生物学
- 分子生物学分子生物学
背景情况:
- 主体免疫细胞利用细胞质传感器来检测病原体并进行抗感染反应.
- 病原体逃避持续感染细胞内监测的机制尚不完全理解.
研究的目的:
- 为了研究Mycobacterium结核病 (Mtb) 如何颠覆宿主细胞内监测.
- 为了确定参与逃避炎症酶介导免疫的细菌因素.
主要方法:
- 研究了Mtb蛋白激酶PknG在准宿主线性无素链组装复合体 (LUBAC) 中的作用.
- 利用生物化学分析分析了HOIL-1L由PknG的酸化及其对LUBAC形成和无处不在的影响.
- 评估了PknG对NLRP3炎症酶组合,细胞因子释放和热的作用.
- 评估了小鼠在体内抗Mtb免疫力,这些小鼠的PknG激酶活性或HOIL-1L相互作用区域受损.
主要成果:
- Mtb PknG的目标是LUBAC复合体,特别是酸化HOIL-1L子单元.
- 通过PknG介导的HOIL-1L的酸化抑制了LUBAC的形成和ASC的泛化,从而抑制了NLRP3炎症酶组合.
- 酸化的HOIL-1L被稳定和激活,导致K48相关的无化和NLRP3.3的降解.
- 破坏PknG的激酶活性或HOIL-1L结合部位会增强小鼠的NLRP3依赖的抗Mtb免疫力.
结论:
- Mtb PknG 颠覆宿主炎症细胞监测通过破坏线性无素机制.
- 细菌激酶劫持LUBAC以促进NLRP3降解,促进持续感染的免疫逃避.
- 准PknG-LUBAC相互作用是加强宿主抗菌素免疫力的潜在策略.
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