Search results
Results from the WOW.Com Content Network
Mitochondrial DNA (mtDNA and mDNA) is the DNA located in the mitochondria organelles in a eukaryotic cell that converts chemical energy from food into adenosine triphosphate (ATP). Mitochondrial DNA is a small portion of the DNA contained in a eukaryotic cell; most of the DNA is in the cell nucleus , and, in plants and algae, the DNA also is ...
In humans, mitochondrial DNA (mtDNA) forms closed circular molecules that contain 16,569 [4] [5] DNA base pairs, [6] with each such molecule normally containing a full set of the mitochondrial genes. Each human mitochondrion contains, on average, approximately 5 such mtDNA molecules, with the quantity ranging between 1 and 15. [ 6 ]
Loogvali et al. (2009) only consider synonymous mutations, they have recalibrated the molecular clock of human mtDNA as 7990 years per synonymous mutation over the mitochondrial genome. [1] Soares et al. (2009) consider both coding and non-coding region mutations to arrive at a single mutation rate, but apply a correction factor to account for ...
The near-absence of genetic recombination in mitochondrial DNA makes it a useful source of information for studying population genetics and evolutionary biology. [152] Because all the mitochondrial DNA is inherited as a single unit, or haplotype, the relationships between mitochondrial DNA from different individuals can be represented as a gene ...
[1] At birth, all copies of mitochondrial DNA are thought to be identical in most humans. [2] Microheteroplasmy is mutations of up to about 2−5% of mitochondrial genomes, and is present in most adults. This refers to hundreds of independent mutations in one organism, with each mutation found in about 1–2% of all mitochondrial genomes. [3]
Mitochondrial matrix has a pH of about 7.8, which is higher than the pH of the intermembrane space of the mitochondria, which is around 7.0–7.4. [5] Mitochondrial DNA was discovered by Nash and Margit in 1963. One to many double stranded mainly circular DNA is present in mitochondrial matrix. Mitochondrial DNA is 1% of total DNA of a cell.
Mitochondrial DNA has been known to encode 13 proteins. Recently, other short protein coding sequences have been identified, and their products are referred to as mitochondria-derived peptides. [15] The mitochondrial-derived peptide, humanin has been shown to protect against Alzheimer's disease, which is considered an age-associated disease. [16]
The theory implicates the mitochondria as the chief target of radical damage, since there is a known chemical mechanism by which mitochondria can produce ROS, mitochondrial components such as mtDNA are not as well protected as nuclear DNA, and by studies comparing damage to nuclear and mtDNA that demonstrate higher levels of radical damage on ...