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Temporal depolarization of mitochondria during M phase
Kotoe Hirusaki1, Kaho Yokoyama1, Kyunghak Cho1
1Division of Biotechnology and Life Sciences, Institute of Engineering, Tokyo University of Agriculture and Technology, Nakacho 2-24-16, Koganei, Tokyo, 184-8588, Japan.
Scientific Reports
|November 24, 2017
Summary
Cellular mitochondria
Area of Science:
- Cell Biology
- Mitochondrial Biology
- Cell Cycle Regulation
Background:
- Cellular homeostasis requires tight control of mitochondrial activity.
- Mitochondrial function during M phase (mitosis) remains poorly understood despite significant cellular changes.
- Understanding mitochondrial regulation during cell division is crucial.
Purpose of the Study:
- To investigate how mitochondrial activity is regulated during M phase.
- To determine changes in mitochondrial membrane potential and reactive oxygen species (ROS) production during cell division.
Main Methods:
- Measurement of mitochondrial membrane potential.
- Assessment of superoxide anion generation using antimycin A.
- Cell cycle analysis.
Main Results:
- Mitochondrial membrane potential remained polarized through metaphase but depolarized during telophase and cytokinesis.
- Superoxide anion generation was significantly reduced during metaphase, even with Complex III inhibition.
- Electron supply to the mitochondrial electron transport chain appears suppressed during M phase.
Conclusions:
- Mitochondrial activity is actively modulated during M phase.
- Suppressed mitochondrial electron transport during M phase may reduce ROS production.
- This regulation could protect cells from ROS-induced damage during division.
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