Related Experiment Video
Updated: Jul 1, 2026
08:17
Optical Coherence Tomography: Imaging Mouse Retinal Ganglion Cells In Vivo
Published on: September 22, 2017
Mitochondrial oxidative phosphorylation in autosomal dominant optic atrophy
Vladimir I Mayorov1, Angela J Lowrey, Valerie Biousse
1Division of Basic Medical Sciences, Mercer University School of Medicine, Macon, GA 31207, USA. mayorov_vi@mercer.edu
BMC Biochemistry
|September 12, 2008
Summary
Autosomal dominant optic atrophy (ADOA) is linked to OPA1 gene mutations. Studies show these mutations affect mitochondrial structure, not electron transport, in ADOA patients.
Area of Science:
- Mitochondrial biology
- Neurogenetics
- Ophthalmology
Background:
- Autosomal dominant optic atrophy (ADOA) causes progressive vision loss due to retinal ganglion cell and optic nerve damage.
- Mutations in the OPA1 gene, encoding a mitochondrial GTPase, are the primary cause of ADOA.
- OPA1 localizes to mitochondrial cristae, crucial for electron transport chain complexes.
Purpose of the Study:
- To investigate the impact of OPA1 mutations on mitochondrial function in ADOA patients.
- To determine if OPA1's role in oxidative phosphorylation is affected in ADOA pathophysiology.
Main Methods:
- Mitochondrial respiratory capacity was assessed.
- Electron transport complex function was analyzed.
- Samples were obtained from ADOA patients with known and unknown OPA1 mutations.
Main Results:
- Mitochondria from ADOA patients with OPA1 mutations did not show altered mitochondrial electron transport.
- Analysis of respiratory capacity and electron transport complex function revealed no significant changes.
Conclusions:
- The study concludes that OPA1's role in mitochondrial structure or fusion, not oxidative phosphorylation, is central to ADOA.
- ADOA pathophysiology is likely driven by disruptions in mitochondrial dynamics rather than impaired energy production.
More Related Videos
08:45Determination of Mitochondrial Respiration and Glycolysis in Ex Vivo Retinal Tissue Samples
Published on: August 4, 2021
09:40Phosphorus-31 Magnetic Resonance Spectroscopy: A Tool for Measuring In Vivo Mitochondrial Oxidative Phosphorylation Capacity in Human Skeletal Muscle
Published on: January 19, 2017
Related Concept Videos
01:46Electron Transport Chain: Complex I and II
The mitochondrial electron transport chain (ETC) is the main energy generation system in the eukaryotic cells. However, mitochondria also produce cytotoxic reactive oxygen species (ROS) due to the large electron flow during oxidative phosphorylation. While Complex I is one of the primary sources of superoxide radicals, ROS production by Complex II is uncommon and may only be observed in cancer cells with mutated complexes.
ROS generation is regulated and maintained at moderate levels necessary...
ROS generation is regulated and maintained at moderate levels necessary...
02:59Animal Mitochondrial Genetics
Among all the organelles in an animal cell, only mitochondria have their own independent genomes. Animal mitochondrial DNA is a double-stranded, closed-circular molecule with around 20,000 base pairs. Mitochondrial DNA is unique in that one of its two strands, the heavy, or H, -strand is guanine rich, whereas the complementary strand is cytosine rich and called the light, or L, -strand. Compared to nuclear DNA, mitochondrial DNA has a very low percentage of non-coding regions and is marked by...
01:48ATP Synthase: Mechanism
In animals, the mitochondrial F1F0 ATP synthase is the key protein that synthesizes ATP molecules through a complex catalytic mechanism. While the nuclear genome encodes the majority of ATP synthase subunits, the mitochondrial genome encodes some of the enzyme's most critical components. The formation of this multi-subunit enzyme is a complex multi-step process regulated at the level of transcription, translation, and assembly. Defects in one or more of these steps can result in decreased ATP...
01:19Translocation of Proteins into the Mitochondria
Mitochondrial precursors are translocated to the internal subcompartments via independent mechanisms involving distinct protein machineries called translocases.
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
01:15Pyruvate Oxidation
After glycolysis, the charged pyruvate molecules enter the mitochondria via active transport and undergo three enzymatic reactions. These reactions ensure that pyruvate can enter the next metabolic pathway so that energy stored in the pyruvate molecules can be harnessed by the cells.
First, the enzyme pyruvate dehydrogenase removes the carboxyl group from pyruvate and releases it as carbon dioxide. The stripped molecule is then oxidized and releases electrons, which are then picked up by NAD+...
First, the enzyme pyruvate dehydrogenase removes the carboxyl group from pyruvate and releases it as carbon dioxide. The stripped molecule is then oxidized and releases electrons, which are then picked up by NAD+...
01:22Photoreceptors and Visual Pathways
At the molecular level, visual signals trigger transformations in photopigment molecules, resulting in changes in the photoreceptor cell's membrane potential. The photon's energy level is denoted by its wavelength, with each specific wavelength of visible light associated with a distinct color. The spectral range of visible light, classified as electromagnetic radiation, spans from 380 to 720 nm. Electromagnetic radiation wavelengths exceeding 720 nm fall under the infrared category, whereas...