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Updated: May 15, 2026
08:15
Understanding the Changes in Mitochondrial Morphology through Dynamic and Three-dimensional Fluorescence Micrographs
Published on: August 15, 2025
MitoSafe hypothesis: safeguarding mitochondrial morphology and innate immunity
Nora Haggerty1, Kentaro Nakamura1, Hiromi Sesaki1
1Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
Trends in Cell Biology
|May 13, 2026
Summary
Cells actively manage mitochondrial size by balancing division and fusion. The Mitochondrial Safeguard (MitoSafe) framework explains how cells adjust mitochondrial dynamics to maintain healthy morphology and function.
Area of Science:
- Cell Biology
- Mitochondrial Dynamics
- Molecular Mechanisms
Background:
- Mitochondria undergo continuous division and fusion, processes crucial for maintaining cellular health.
- The mechanisms by which cells sense and actively regulate mitochondrial morphology remain incompletely understood.
Purpose of the Study:
- To propose a conceptual framework, Mitochondrial Safeguard (MitoSafe), explaining how cells monitor and adjust mitochondrial size.
- To elucidate the cellular branches involved in rebalancing mitochondrial division and fusion based on mitochondrial size.
Main Methods:
- This is an opinion article, presenting a conceptual framework based on existing literature.
- It integrates findings on mitochondrial morphology regulation, including fusion and division processes.
Main Results:
- The MitoSafe framework proposes four branches: activating fusion/inhibiting division in small mitochondria, and activating division/inhibiting fusion in enlarged mitochondria.
- Recent evidence indicates fusion suppression in enlarged mitochondria, a key aspect of MitoSafe.
Conclusions:
- Dysregulation of the MitoSafe pathway, particularly fusion suppression in enlarged mitochondria, is linked to mitochondrial dysfunction.
- Implicated factors in dysregulation include Parkin, PINK1, SLC25A3, SOD1, and cytochrome-c oxidase, leading to inflammation via STING.
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