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Assessment of Open Probability of the Mitochondrial Permeability Transition Pore in the Setting of Coenzyme Q Excess
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The Permeability Transition in Plant Mitochondria: The Missing Link
Marco Zancani1, Valentino Casolo1, Elisa Petrussa1
1Plant Biology Unit, Department of Agricultural and Environmental Sciences, University of Udine Udine, Italy.
Frontiers in Plant Science
|December 24, 2015
Summary
Mitochondrial ATP synthase dimers may form the permeability transition pore (PTP) in plants, similar to other organisms. This pore regulates mitochondrial permeability and is linked to cell death, with potential origins in molecular exaptation.
Area of Science:
- Mitochondrial physiology
- Cell biology
- Biochemistry
Background:
- Mitochondrial ATP synthesis relies on inner membrane impermeability.
- Increased permeability, termed permeability transition (PT), is mediated by a permeability transition pore (PTP).
- PTP opening, triggered by matrix Ca(2+), causes mitochondrial swelling and protein release.
Purpose of the Study:
- To investigate the role of mitochondrial ATP synthase dimers as the physical basis for the permeability transition pore (PTP) in plants.
- To discuss the potential function of ATP synthase dimers as PTP in plant mitochondria.
- To provide a hypothetical explanation for the evolutionary origin of PTP.
Main Methods:
- Review of current evidence on PTP in mammalian, yeast, and Drosophila mitochondria.
- Analysis of existing data on plant mitochondria, including swelling and protein release linked to programmed cell death.
- Discussion of indirect evidence for PT in plant cell cultures.
Main Results:
- Mitochondrial ATP synthase dimers are identified as the physical basis for PT in mammalian, yeast, and Drosophila.
- PT in plant mitochondria is less understood, with limited direct evidence in isolated mitochondria.
- Swelling and protein release in plant mitochondria are associated with programmed cell death.
Conclusions:
- Mitochondrial ATP synthase dimers are a strong candidate for forming the PTP in plant mitochondria.
- Further research is needed to confirm the role of ATP synthase dimers as PTP in plants.
- The PTP may have originated through molecular exaptation.
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