This open access review paper looks over current thinking on the role of mutations in mitochondrial DNA in the decline of stem cell activity in aging. Every cell contains a swarm of mitochondria, the evolved descendants of symbiotic bacteria now responsible for generating chemical energy store molecules. Each contains a small amount of mitochondrial DNA, the last remnant of the original bacterial genome that hasn’t either been lost over time or moved to the cell nucleus. Mutational damage in this DNA can produce significant cellular dysfunction, and unfortunately it is a good deal less robust and protected than the DNA of the cell nucleus. It is also right next to energetic chemical processes that produce reactive molecules as a byproduct, and it replicates more frequently than nuclear DNA, all of which suggests a greater rate of damage and error. In long-lived and important stem cell populations, this process is probably important.
mutationsmitochondrial DNAdecline of stem cell activity in agingmitochondriachemical energy store moleculesgenomecan produce significant cellular dysfunctioncell nucleusenergetic chemical processesproduce reactive moleculesnuclear DNA
Ageing is a process where tissue gradually loses homeostasis and regeneration. This process is systemic and closely associated to age-related changes in somatic stem cells. These cells renew themselves
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