title: Adult neural stem cells: plastic or restricted neuronal fates?
abstract: During embryonic development, the telencephalon is specified along its axis through morphogenetic gradients, leading to the positional-dependent generation of multiple neuronal types. After embryogenesis, however, the fate of neuronal progenitors becomes more restricted, and they generate only a subset of neurons. Here, we review studies of postnatal and adult neurogenesis, challenging the notion that fixed genetic programs restrict neuronal fate. We hypothesize that the adult brain maintains plastic neural stem cells that are capable of responding to changes in environmental cues and generating diverse neuronal types. Thus, the limited diversity of neurons generated under normal conditions must be actively maintained by the adult milieu.
authors.affiliation: Department of Physiology and Membrane Biology, University of California Davis, Shriners Hospital for Children Northern California, Sacramento, CA 95817, USA. ebsequerra@ucdavis.edu
authors.forename: Eduardo B
authors.initials: EB
authors.lastname: Sequerra
authors.forename: Marcos R
authors.initials: MR
authors.lastname: Costa
authors.forename: João R L
authors.initials: JR
authors.lastname: Menezes
authors.forename: Cecilia
authors.initials: C
authors.lastname: Hedin-Pereira
mesh_terms: D000818:Animals; D002465:Cell Movement; D004622:Embryo, Mammalian / Q000378:metabolism / Q000502:physiology; D047108:Embryonic Development; D059330:GABAergic Neurons / Q000378:metabolism / Q000502:physiology*; D053823:Hedgehog Proteins / Q000378:metabolism / Q000502:physiology; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D051379:Mice; D058953:Neural Stem Cells / Q000378:metabolism / Q000502:physiology*; D055495:Neurogenesis; D009473:Neuronal Plasticity; D055153:Stem Cell Niche; D009435:Synaptic Transmission; D013687:Telencephalon / Q000378:metabolism / Q000502:physiology
chemical_list: D053823:Hedgehog Proteins; D018398:Homeodomain Proteins; C465570:Shh protein, mouse; C487377:Tlx3 protein, mouse
keywords: Adult neurogenesis; Cerebral cortex; Neuronal specification; Olfactory bulb; Subventricular zone