Mitochondrial DNA Copy Number in Health and Disease

Every cell contains a herd of hundreds of mitochondria, bacterial-like structures that contain a small circular genome, the mitochondrial DNA. Mitochondria replicate to make up their numbers, and are culled by the quality control mechanism of mitophagy when damaged. Their primary task is to conduct the energetic chemistry that packages the energy store molecule adenosine triphosphate, used to power cellular processes. Mitochondrial function declines with age for reasons that are still comparatively poorly understood; damage to mitochondrial DNA is involved, as are changes in the expression of proteins necessary for mitophagy to function correctly. One crude way to assess the state of mitochondria in cells is to count the number of copies of mitochondrial DNA that are present, a number that changes with aging and disease. While there is plenty of evidence for this to correlate with mitochondrial dysfunction, it doesn't necessarily directly reflect the most interesting mechanisms in mitochondrial aging, which are all forms of damage to mitochondria and mitochondrial DNA, rather than outright loss of mitochondria. There is a web of damage and dysfunction, and while various different parts of it will tend to be in sync, that doesn't have to imply direct causal connections. Thinking outside the nucleus: Mitochondrial DNA copy number in health and disease Mitochondrial dysfunction, generally characterized as a loss of efficiency in oxidative phosphorylation, ...
Source: Fight Aging! - Category: Research Authors: Tags: Medicine, Biotech, Research Source Type: blogs