State Key Laboratory of Agricultural Microbiology, Hubei Hongshan Laboratory, National Engineering Research Center of Microbial Pesticides, Huazhong Agricultural University, Wuhan, 430070, China.
Program in Molecular Medicine, University of Massachusetts Chan Medical School Worcester, Worcester, MA, 01605-2377, USA.
Commun Biol. 2022 Jun 30;5(1):643. doi: 10.1038/s42003-022-03589-1.
Pathogen recognition and the triggering of host innate immune system are critical to understanding pathogen-host interaction. Cellular surveillance systems have been identified as an important strategy for the identification of microbial infection. In the present study, using Bacillus thuringiensis-Caenorhabditis elegans as a model, we found an approach for surveillance systems to sense pathogens. We report that Bacillus thuringiensis Cry5Ba, a typical pore-forming toxin, caused mitochondrial damage and energy imbalance by triggering potassium ion leakage, instead of directly targeting mitochondria. Interestingly, we find C. elegans can monitor intracellular energy status to trigger innate immune responses via AMP-activated protein kinase (AMPK), secreting multiple effectors to defend against pathogenic attacks. Our study indicates that the imbalance of energy status is a prevalent side effect of pathogen infection. Furthermore, the AMPK-dependent surveillance system may serve as a practicable strategy for the host to recognize and defense against pathogens.
病原体识别和宿主固有免疫系统的触发对于理解病原体-宿主相互作用至关重要。细胞监测系统已被确定为识别微生物感染的重要策略。在本研究中，我们使用苏云金芽孢杆菌-秀丽隐杆线虫作为模型，发现了一种监视系统来感知病原体的方法。我们报告称，典型的孔形成毒素苏云金芽孢杆菌 Cry5Ba 通过触发钾离子泄漏而不是直接靶向线粒体，导致线粒体损伤和能量失衡。有趣的是，我们发现秀丽隐杆线虫可以通过 AMP 激活的蛋白激酶 (AMPK) 监测细胞内能量状态，通过分泌多种效应物来触发先天免疫反应，以抵御致病攻击。我们的研究表明，能量状态的失衡是病原体感染的一种普遍副作用。此外，AMPK 依赖性监测系统可能是宿主识别和防御病原体的一种可行策略。
