Journal
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
Volume 112, Issue 1, Pages 130-135Publisher
NATL ACAD SCIENCES
DOI: 10.1073/pnas.1415261112
Keywords
mitochondrial membrane proteins; proton diffusion; direct stochastic optical reconstruction microscopy; uncoupling; reactive oxygen species
Categories
Funding
- Austrian Research Fund [F3519-B20, P25123-B20]
- Federation of European Biochemical Societies (FEBS)
- Austrian Science Fund (FWF) [P 25123] Funding Source: researchfish
- Austrian Science Fund (FWF) [P25123] Funding Source: Austrian Science Fund (FWF)
Ask authors/readers for more resources
Because different proteins compete for the proton gradient across the inner mitochondrial membrane, an efficient mechanism is required for allocation of associated chemical potential to the distinct demands, such as ATP production, thermogenesis, regulation of reactive oxygen species (ROS), etc. Here, we used the superresolution technique dSTORM (direct stochastic optical reconstruction microscopy) to visualize several mitochondrial proteins in primary mouse neurons and test the hypothesis that uncoupling protein 4 (UCP4) and F0F1-ATP synthase are spatially separated to eliminate competition for the proton motive force. We found that UCP4, F0F1-ATP synthase, and the mitochondrial marker voltage-dependent anion channel (VDAC) have various expression levels in different mitochondria, supporting the hypothesis of mitochondrial heterogeneity. Our experimental results further revealed that UCP4 is preferentially localized in close vicinity to VDAC, presumably at the inner boundary membrane, whereas F0F1-ATP synthase is more centrally located at the cristae membrane. The data suggest that UCP4 cannot compete for protons because of its spatial separation from both the proton pumps and the ATP synthase. Thus, mitochondrial morphology precludes UCP4 from acting as an uncoupler of oxidative phosphorylation but is consistent with the view that UCP4 may dissipate the excessive proton gradient, which is usually associated with ROS production.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available