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Mitochondrial membrane tension governs fission
Dora Mahecic1, Lina Carlini1, Tatjana Kleele1
1Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), Route Cantonale, 1015 Lausanne, Switzerland; National Centre for Competence in Research Programme Chemical Biology, Geneva, Switzerland.
Cell Reports
|April 14, 2021
Summary
Mitochondria are under tension during fission. Reduced mitochondrial membrane tension hinders constriction division, suggesting tension is crucial for this cellular process.
Area of Science:
- Cell Biology
- Biophysics
Background:
- Mitochondrial fission is essential for cellular function.
- Molecular machinery coordinates mitochondrial constriction.
- The role of membrane tension in fission remains unclear.
Purpose of the Study:
- To investigate the role of mitochondrial membrane tension in the process of mitochondrial fission.
- To quantify membrane tension in living mammalian cells during fission.
Main Methods:
- Live-cell structured illumination microscopy (SIM) to visualize mitochondrial dynamics.
- Fluorescence lifetime-based sensor to measure mitochondrial membrane tension.
- Analysis of mitochondrial tubule diameters and constriction dynamics.
Main Results:
- Mitochondria exhibit significant membrane tension during fission.
- Reduced mitochondrial tension decreased the probability of constriction division.
- Constriction initiation rates were unaffected by reduced tension.
Conclusions:
- Mitochondrial membrane tension plays a critical role in regulating the division of constrictions during fission.
- A biophysical model incorporating membrane tension and bending energy explains fission dynamics.
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