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Updated: Apr 29, 2026
10:39
Visualization of ATP Synthase Dimers in Mitochondria by Electron Cryo-tomography
Published on: September 14, 2014
33.9K
Whole cell cryo-electron tomography suggests mitochondria divide by budding
1Department of Biological Chemistry and Molecular Pharmacology,Harvard Medical School,240 Longwood Avenue,Boston,MA 02115,USA.
Summary
Mitochondria division in eukaryotes may occur by budding, not just binary fission. This study used cryo-electron tomography to reveal small, budding mitochondria connected to larger networks in intact cells.
Area of Science:
- Cell Biology
- Mitochondrial Biology
- Structural Biology
Background:
- Eukaryotic cells require sufficient mitochondria, necessitating mitochondrial division.
- Mitochondrial division was traditionally attributed to binary fission, involving dynamin-related protein (Drp1) and the endoplasmic reticulum.
- Previous studies relied on fluorescence and conventional electron microscopy.
Purpose of the Study:
- To investigate the mechanism of mitochondrial division in intact eukaryotic cells.
- To challenge the prevailing model of mitochondrial binary fission.
- To provide high-resolution structural evidence of mitochondrial division dynamics.
Main Methods:
- Whole cell cryo-electron tomography (cryo-ET) was employed.
- Mitochondrial division was visualized in frozen hydrated intact HeLa cells.
- High-resolution imaging of cellular structures was achieved.
Main Results:
- A significant population of small mitochondria were observed.
- These small mitochondria were seen protruding from and connected to larger mitochondria or mitochondrial networks.
- The observed morphology suggests a budding mechanism for mitochondrial division.
Conclusions:
- The study provides evidence supporting mitochondrial division by budding.
- This finding challenges the long-held view of binary fission as the sole mechanism.
- Cryo-electron tomography offers novel insights into mitochondrial dynamics.
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