The mTORC1 protein is famous for triggering explosive cell growth, but it is secretly the master controller that keeps brain stem cells in a perfect state of deep sleep.
Dormant neural stem cells in the adult brain were previously thought to be passive bystanders waiting for a growth signal to wake them up. The protein mTORC1 acts as a quality control manager that regulates how deep that slumber goes. Cells without this protein fall into a coma so deep they can never be revived to repair brain tissue. This mechanism ensures the brain maintains a reserve of ready to wake cells for healing after an injury. Understanding this active sleep state gives us a new way to combat age-related brain decline by keeping stem cells responsive. Future treatments might target this pathway to wake up the brain's own repair kit more effectively.
mTORC1 supports progression toward activation competence in quiescent adult neural stem cells
bioRxiv · 10.64898/2026.05.02.722413
Cerebellar pathways form extensive structural circuits linking the cerebellum with the brainstem, thalamus, and cerebrum, underlying motor, cognitive, and affective functions. Diffusion MRI tractography provides the only non-invasive method for mapping these pathways in vivo, but reconstruction of cerebellar connectivity remains challenging due to crossing fibers, peduncular bottlenecks, decussations, multi-synaptic circuits, and numerous small nuclei that define pathway origins and terminations