title: Vasculature guides migrating neuronal precursors in the adult mammalian forebrain via brain-derived neurotrophic factor signaling.
abstract: Adult neuronal precursors retain the remarkable capacity to migrate long distances from the posterior (subventricular zone) to the most anterior [olfactory bulb (OB)] parts of the brain. The knowledge about the mechanisms that keep neuronal precursors in the migratory stream and organize this long-distance migration is incomplete. Here we show that blood vessels precisely outline the migratory stream for new neurons in the adult mammalian forebrain. Real-time video imaging of cell migration in the acute slices demonstrate that neuronal precursors are retained in the migratory stream and guided into the OB by blood vessels that serve as a physical substrate for migrating neuroblasts. Our data suggest that endothelial cells of blood vessels synthesize brain-derived neurotrophic factor (BDNF) that fosters neuronal migration via p75NTR expressed on neuroblasts. Interestingly, GABA released from neuroblasts induces Ca(2+)-dependent insertion of high-affinity TrkB receptors on the plasma membrane of astrocytes that trap extracellular BDNF. We hypothesize that this renders BDNF unavailable for p75NTR-expressing migrating cells and leads to their entrance into the stationary period. Our findings provide new insights into the functional organization of substrates that facilitate the long-distance journey of adult neuronal precursors.
authors.affiliation: The Cellular Neurobiology Unit, Centre de Recherche Université Laval Robert-Giffard, Québec, Québec, Canada G1J 2G3.
authors.forename: Marina
authors.initials: M
authors.lastname: Snapyan
authors.forename: Morgane
authors.initials: M
authors.lastname: Lemasson
authors.forename: Monika S
authors.initials: MS
authors.lastname: Brill
authors.forename: Mathieu
authors.initials: M
authors.lastname: Blais
authors.forename: Mireille
authors.initials: M
authors.lastname: Massouh
authors.forename: Jovica
authors.initials: J
authors.lastname: Ninkovic
authors.forename: Claude
authors.initials: C
authors.lastname: Gravel
authors.forename: François
authors.initials: F
authors.lastname: Berthod
authors.forename: Magdalena
authors.initials: M
authors.lastname: Götz
authors.forename: Philip A
authors.initials: PA
authors.lastname: Barker
authors.forename: André
authors.initials: A
authors.lastname: Parent
authors.forename: Armen
authors.initials: A
authors.lastname: Saghatelyan