MItochondrial Epigenetics in Aging and Cancer

Mitochondria, the power plants of the cell, are the descendants of ancient symbiotic bacteria, and still carry a remnant circular genome, separately from the DNA of the cell nucleus. Some forms of mutational damage to mitochondrial DNA, and the downstream consequences of that damage, are thought to be an important contributing cause of degenerative aging, but what about epigenetic changes? Epigenetic aging in nuclear DNA is a hot topic at the moment, so it is inevitable that attention would turn to the epigenetics of the much smaller mitochondrial genome. Inflammation is a defining factor in disease progression; epigenetic modifications of this first line of defence pathway can affect many physiological and pathological conditions, like aging and tumorigenesis. Inflammageing, one of the hallmarks of aging, represents a chronic, low key but a persistent inflammatory state. Oxidative stress, alterations in mitochondrial DNA (mtDNA) copy number and mis-localized extra-mitochondrial mtDNA are suggested to directly induce various immune response pathways. This could ultimately perturb cellular homeostasis and lead to pathological consequences. Epigenetic remodelling of mtDNA by DNA methylation, post-translational modifications of mtDNA binding proteins and regulation of mitochondrial gene expression by nuclear DNA or mtDNA encoded non-coding RNAs, are suggested to directly correlate with the onset and progression of various types of cancer. Mitochondria are also ca...
Source: Fight Aging! - Category: Research Authors: Tags: Daily News Source Type: blogs