Stabilization of neuronal connections and the axonal cytoskeleton.

Stabilization of axonal connections is an underappreciated, but critical, element in development and maintenance of neuronal functions. The ability to maintain the overall architecture of the brain for decades is essential for our ability to process sensory information efficiently, coordinate motor activity, and retain memories for a lifetime. While the importance of the neuronal cytoskeleton in this process is acknowledged, little has been known about specializations of the axonal cytoskeleton needed to stabilize neuronal architectures. A novel post-translational modification of tubulin that stabilizes normally dynamic microtubules in axons has now been identified. Polyamination appears to be enriched in axons and is developmentally regulated with a time course that correlates with increased microtubule stabilization. Identifying one of the molecular mechanisms for maintaining neuronal connections creates new research avenues for understanding the role of stabilizing neuronal architecture in neuronal function and in neuropathology.