Evidence for a Mechanism that Operates in Oocytes to Reduce Mitochondrial DNA Mutation Rate

Researchers here show that, in primates, oocyte cells are more protected from mutations to mitochondrial DNA in later life. This suggests that one or more mechanisms are operating to produce this outcome. Given that mitochondrial DNA mutations are implicated in age-related loss of mitochondrial function and other aspects of aging, the existence of protective mechanisms is potentially interesting. It is not as interesting as the ability to repair or replace damaged mitochondrial DNA, of course. Mechanisms that can only produce sizable differences by operating over long periods of time are a poor foundation upon which to build rejuvenation therapies. New mutations occur at increasing rates in the mitochondrial genomes of developing egg cells in aging rhesus monkeys, but the increases appear to plateau at a certain age and are not as large as those seen in non-reproductive cells, like muscle and liver. A new study using an accurate DNA sequencing methodology suggests that there may be a protective mechanism that keeps the mutation rate in reproductive cells relatively lower compared to other tissues in primates, a fact that could be related to the primate - and therefore human - propensity to reproduce at later ages. Mitochondria are cellular organelles - often called the powerhouse of the cell because of their role in energy production - that have a genome of their own separate from the cell's nuclear genome. Researchers sequenced the mitochondrial genome from m...
Source: Fight Aging! - Category: Research Authors: Tags: Daily News Source Type: blogs