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Updated: Sep 6, 2026
Histological Examination of Mitochondrial Morphology in a Parkinson's Disease Model
Published on: June 23, 2023
Some observations on negatively stained mitochondria
Abstract:
A particulate component of mitochondria is described which is observed in negatively stained preparations of unfixed whole mitochondria or their fragments. It consists of a roughly spherical particle, approximately 85 A in diameter, found on the surface of the cristae and probably also on the side of the mitochondrial envelope which faces the matrix. It is attached to the underlying membrane by a narrow stalk 40 to 50 A long. The particle appears to be rather labile and it is destroyed or at least rendered unrecognizable by all conventional fixatives used in electron microscopy, especially OsO(4).
Insights
A novel particulate component of mitochondria was discovered on the surface of cristae. This labile particle, approximately 85 Angstroms in diameter, is destroyed by conventional electron microscopy fixatives.
Area of Science:
- Mitochondrial biology
- Cellular ultrastructure
- Electron microscopy
Background:
- Mitochondria are vital organelles responsible for cellular energy production.
- The precise ultrastructure of mitochondria is crucial for their function.
- Previous studies have not fully characterized all mitochondrial components.
Purpose of the Study:
- To describe a previously unidentified particulate component of mitochondria.
- To characterize the morphology and location of this novel particle.
- To investigate the stability of this particle under electron microscopy preparation conditions.
Main Methods:
- Negative staining of unfixed whole mitochondria and mitochondrial fragments.
- Electron microscopy imaging to visualize particulate structures.
- Analysis of particle size, shape, and attachment to mitochondrial membranes.
Main Results:
- A roughly spherical particle, approximately 85 Angstroms in diameter, was observed.
- The particle is located on the surface of mitochondrial cristae and the matrix-facing side of the inner membrane.
- It is attached by a narrow stalk (40-50 Angstroms) and is labile, being destroyed by conventional fixatives like OsO(4).
Conclusions:
- A distinct particulate component exists on mitochondrial membranes.
- This particle's lability suggests it plays a role sensitive to chemical fixation.
- Further research is needed to determine the function of this newly identified mitochondrial component.
