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Published on: January 27, 2021
The MICOS Complex Subunit Mic60 is Hijacked by Intracellular Bacteria to Manipulate Mitochondrial Dynamics and
Changyong Cheng1, Mianmian Chen1, Jing Sun1
1Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province, Zhejiang Provincial Engineering Research Center for Animal Health Diagnostics & Advanced Technology, Zhejiang International Science and Technology Cooperation Base for Veterinary Medicine and Health Management, China-Australia Joint Laboratory for Animal Health Big Data Analytics, College of Veterinary Medicine of Zhejiang A&F University, 666 Wusu Street, Lin'an District, Hangzhou, Zhejiang Province, 311300, China.
Abstract:
Host mitochondria undergo fission and fusion, which bacteria often exploit for their infections. In this study, the underlying molecular mechanisms are aimed to clarify through which Listeria monocytogenes (L. monocytogenes), a human bacterial pathogen, manipulates mitochondrial dynamics to enhance its pathogenicity. It is demonstrated that L. monocytogenes triggers transient mitochondrial fission through its virulence factor listeriolysin O (LLO), driven by LLO's interaction with Mic60, a core component of the mitochondrial contact site and the cristae organizing system (MICOS). Specifically, Phe251 within LLO is identify as a crucial residue for binding to Mic60, crucial for LLO-induced mitochondrial fragmentation and bacterial pathogenicity. Importantly, it is that Mic60 affect the formation of F-actin tails recruited by L. monocytogenes, thereby contributing to intracellular bacterial infection. Mic60 plays a critical role in mediating changes in mitochondrial morphology, membrane potential, and reactive oxidative species (ROS) production, and L. monocytogenes infection exacerbates these changes by affecting Mic60 expression. These findings unveil a novel mechanism through which intracellular bacteria exploit host mitochondria, shedding light on the complex interplay between hosts and microbes during infections. This knowledge holds promise for developing innovative strategies to combat bacterial infections.
Insights
Listeria monocytogenes manipulates host mitochondria via listeriolysin O (LLO) and Mic60, causing fission and enhancing bacterial infection. This interaction impacts mitochondrial function and bacterial pathogenicity.
Area of Science:
- Microbiology
- Cell Biology
- Pathogenesis
Background:
- Host mitochondria dynamics (fission/fusion) are crucial for cellular processes.
- Intracellular bacteria, like Listeria monocytogenes, often exploit host cell machinery for survival and replication.
- Mitochondrial dysfunction is increasingly recognized as a factor in infectious diseases.
Purpose of the Study:
- To elucidate the molecular mechanisms by which Listeria monocytogenes manipulates host mitochondrial dynamics.
- To identify specific bacterial factors and host proteins involved in this interaction.
- To understand how this manipulation contributes to bacterial pathogenicity.
Main Methods:
- Investigated the role of Listeria monocytogenes virulence factor listeriolysin O (LLO).
- Utilized biochemical assays to study the interaction between LLO and Mic60, a component of the MICOS complex.
- Analyzed the impact of LLO-Mic60 interaction on mitochondrial morphology, membrane potential, ROS production, and F-actin tail formation.
Main Results:
- L. monocytogenes triggers transient mitochondrial fission through LLO's interaction with Mic60.
- A specific residue, Phe251 in LLO, is critical for Mic60 binding, mitochondrial fragmentation, and bacterial pathogenicity.
- Mic60 influences L. monocytogenes-recruited F-actin tails and its expression is affected by infection, altering mitochondrial function.
Conclusions:
- L. monocytogenes hijacks host mitochondrial dynamics via LLO-Mic60 interaction to promote infection.
- This mechanism involves modulation of mitochondrial morphology, membrane potential, ROS, and F-actin dynamics.
- Understanding this host-pathogen interplay offers potential for novel anti-bacterial strategies.
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