Neuroscientists from Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) have discovered that certain RNA molecules in nerve cells in the brain last a lifetime without being renewed. This finding, which has been published in the journal Science, sheds light on the aging process of the brain and its relevance to degenerative diseases. The research team hopes that by understanding the role of these long-lived RNAs, they can gain insight into how to effectively treat neurodegenerative illnesses such as Alzheimer’s, which are linked to aging neurons.
While most cells in the human body are regularly renewed, the heart, pancreas, and brain contain cells that do not renew throughout the lifespan. Aging neurons are a key risk factor for neurodegenerative diseases, highlighting the importance of understanding the aging process at a cellular level. Prof. Dr. Tomohisa Toda, Professor of Neural Epigenomics at FAU, emphasizes the need for a basic understanding of aging and the key components involved in maintaining cell function for developing effective treatment concepts.
The research team, in collaboration with neuroscientists from Dresden, La Jolla (USA), and Klosterneuburg (Austria), identified a key component of brain aging: the long-lived RNA molecules that protect genetic material exist just as long as the neurons themselves. This discovery challenges the notion that most RNA molecules are short-lived and constantly reconstructed. By marking and tracking the lifespan of these RNAs in mice brain cells, the researchers were able to confirm the presence of long-lived RNAs in both neurons and somatic adult neural stem cells in the brain of two-year-old animals.
The long-lived RNAs, referred to as LL-RNA, were found to be located in the cells’ nuclei, closely connected to chromatin, which is a complex of DNA and proteins that form chromosomes. This suggests that LL-RNAs play a crucial role in regulating chromatin and maintaining genome stability in nerve cells. In an in-vitro experiment with adult neural stem cell models, reducing the concentration of LL-RNAs resulted in impaired chromatin integrity, further supporting the hypothesis that these molecules are essential for long-term cell regulation and maintenance.
The researchers believe that LL-RNAs are instrumental in the long-term regulation of genome stability and the preservation of nerve cells throughout life. Their future research aims to delve deeper into the biophysical mechanisms behind the long-term conservation of LL-RNAs and uncover their biological function in chromatin regulation. Understanding how aging affects these mechanisms will provide valuable insights into neurodegenerative diseases and potentially lead to novel treatment approaches targeting the aging brain.
