Neuronal Chain Gangs: Homotypic Contacts Support Migration into the Olfactory Bulb

A great deal of attention in the field of developmental neurobiology is presently focused on the rodent olfactory bulb, which processes signals from the nasal epithelium and relays them to the brain. The olfactory bulb is the ultimate destination of an extraordinary population of migrating neuroblasts that have been a source of intense interest for two reasons. First, because these cells are generated well into adult life, they may provide clues to the regenerative capacity of the adult brain and strategies for therapeutic approaches to neurological disorders. Second, these cells migrate in a fashion that differs from the well-characterized glial-guided mechanism employed by radially migrating neurons and the molecular basis for their migration appears to be unfolding at a particularly rapid rate. The present minireview focuses on recent studies that have unveiled the cellular and molecular details of this newly described mode of migration.