Journal of Cell Science & Therapy
Open Access

Abstract

Structural and Chemical Influences on Neuronal Migration in the Adult Rostral Migratory Stream

Michael P Kahle and Gregory J Bix

Neurogenesis, the birth of new neurons, occurs throughout life in the subventricular zone (SVZ) lining the lateral ventricles. New neurons in the adult SVZ can undergo tangential migration through the rostral migratory stream (RMS) to the olfactory bulb (OB). This migration is facilitated by other neurons via homophilic migration whereby chains of neurons support saltatory migration through the RMS. Additionally, astrocyte end feet surround the RMS preventing significant extravasation and influencing migration. Finally, blood vessels are oriented parallel within the RMS where they profoundly affect neuronal migration by secreting protective molecular factors, and serving as a physical scaffold for migrating neuroblasts thereby providing a path-of-least-resistance for neuronal migration. Among the many factors influencing neuronal migration are GABA, VEGF, BDNF, PSA-NCAM and L1 CAMs, β1 integrins, netrins, slits, ephrins, semaphorins, matrix metalloproteinases and extracellular matrix components. Understanding influences on adult neurogenesis and neuronal migration is important because these self-repair mechanisms are induced following many CNS injuries. Although this endogenous regeneration is insufficient for meaningful repair in most cases, therapies could potentially enhance these processes to improve clinical outcome.