A paper recently published by Dr. Ádám Sturm and Dr. Tibor Vellai from Eötvös Loránd University uncovers the critical role of mitochondrial DNA, as well as the different ways in which it can be modified and how these modifications impact the viability of the mitochondria in our cells – and thereby the health and longevity of the organism itself.
Ancient Guest – Vital Helper
Almost every cell type in the human body contains hundreds, and at times thousands, of mitochondria, small organelles which are responsible for the production of energy for the cell by absorbing atmospheric oxygen. The origin of mitochondria is unknown, but they are speculated to have been independent organisms that were engulfed by prokaryotic cells early in the history of life on earth, and created a symbiosis that lasts to this day.
Every single mitochondrion contains its own complement of mitochondrial DNA, or mtDNA, separately from the DNA in the cell’s nucleus, which includes genetic blueprints for the production of the mitochondrion’s own molecular building blocks.
Discovery of the Mitochondrial Epigenetic Clock
N6-methyladenine (6mA) is a DNA modification where a methyl group is added to the adenine base at the nitrogen-6 position. In mitochondrial DNA (mtDNA), 6mA plays a role in regulating gene expression and maintaining mitochondrial function. This epigenetic modification can influence the replication and transcription of mitochondrial genes by affecting the binding of transcription factors and other proteins involved in these processes. Additionally, 6mA may contribute to the overall structural stability of mtDNA and protect it from damage, thereby playing a role in mitochondrial health and energy production.
By tracking these 6mA modifications, scientists can predict how long the mitochondria will last, and this biomarker may serve by extension to predict the lifespan of an entire cell population, tissue type, and even an entire multicellular organism.
Location: Eötvös Loránd University, Budapest, Hungary
Source: N6-Methyladenine Progressively Accumulates in Mitochondrial DNA during Aging
https://www.mdpi.com/1422-0067/24/19/14858