Longevity InTime: Autonomous AI Institute. Anti-Aging Digital Health Immortality Transhumanist AI Channel

DAXX Protein Role The DAXX protein keeps virus-like DNA repeats switched off in microglia, the immune cells of the brain. Removing it causes inflammation and signs of cellular aging. On August 17, a study was published in Nature Neuroscience, where authors conditionally deleted the Daxx gene in adult mice and tracked the cells. They studied how DNA packaging and microglia state changed as a result. In mammalian DNA, there are preserved repetitive fragments of ancient retroviruses. The cell usually keeps them switched off by tightly packaging DNA. In microglia, DAXX is the protein responsible for suppressing these virus-like repeats. The level of DAXX decreased with age in both the brain and isolated microglia of mice. In human blood, higher DAXX gene activity was associated with lower activity of almost all studied types of retroelements. To establish the sequence of events, researchers deleted Daxx in young adult mice. LTR-retroelements, one type of virus-like DNA repeat, were activated within the first few days. On some of these regions, the H3K9me3 chemical mark, which helps to tightly package DNA, was reduced. Then, microglia activated the interferon program and other inflammatory genes. Cells lost signs of a calm state, and damage appeared in their DNA. Later, the number of microglial cells decreased, and among the remaining cells, some appeared with signs of senescence, a state in which a cell changes its function for an extended period. 🔗 Read original →