Study Shows Mitochondria 'Throw' Their DNA into Our Brain Cells

MICROBIOLOGY

8/23/2024

Researchers agree that mitochondria, direct descendants of ancient bacteria, still hold many mysteries that are not yet fully understood. This was further highlighted by findings published in PLOS Biology in August 2024, revealing that mitochondria are capable of transferring DNA into the nuclear genome, known as Numts (nuclear mitochondrial DNA segments). In the study, researchers at Columbia University Irving Medical Center found that post-mitotic brain tissue contains more Numts compared to blood cells, after analyzing brain and blood samples from 1,187 individuals. The analysis also revealed a 5.5-fold higher number of Numts in the dorsolateral prefrontal cortex compared to the cerebellum, with individuals without cognitive impairments having more Numts in their brains. Additionally, aging model experiments using fibroblast cells showed that one Numt accumulates approximately every 13 days and increases more rapidly in cells with mutations causing mitochondrial DNA instability, such as mutations in the SURF1 gene, which resulted in a 4.7-fold higher accumulation of Numts. These findings provide new insights into how human mitochondria may affect health through mechanisms of genomic instability.

Source: https://doi.org/10.1371/journal.pbio.3002723