title: Pax6 influences the time and site of origin of glial precursors in the ventral neural tube.
abstract: Neuroepithelial precursors in the ventral ventricular zone (VZ) of the spinal cord generate motor neurons (MNs) and interneurons, and then a subset of precursors starts to produce oligodendrocyte progenitors (OLPs). We show that OLPs originate in the ventral-most part of the Pax6-positive VZ, which at earlier times generates somatic (Isl2/Lim3-positive) MNs. In Small eye (Pax6-deficient) mice, the origin of OLPs is shifted dorsally and both OLPs and Isl2/Lim3 MNs are delayed. We suggest that somatic MNs and OLPs are generated sequentially from a common set of MN-OL precursors whose position in the VZ is influenced by Pax6. Neuron-glia fate switching might be a preprogrammed property of these precursors or a response to feedback from newly generated neurons. OLs developed normally in explants of Isl1(-/-) spinal cords, which lack MNs, arguing against feedback control and suggesting that the neuron-glia switch is an intrinsic developmental program in a specific subset of neural precursors.
authors.affiliation: Department of Biology, University College London, Gower Street, London, WC1E 6BT.
authors.forename: T
authors.initials: T
authors.lastname: Sun
authors.forename: N P
authors.initials: NP
authors.lastname: Pringle
authors.forename: A P
authors.initials: AP
authors.lastname: Hardy
authors.forename: W D
authors.initials: WD
authors.lastname: Richardson
authors.forename: H K
authors.initials: HK
authors.lastname: Smith
mesh_terms: D000818:Animals; D003433:Crosses, Genetic; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D005314:Embryonic and Fetal Development; D005136:Eye Proteins / Q000235:genetics / Q000502:physiology; D005260:Female; D018507:Gene Expression Regulation, Developmental; D006579:Heterozygote; D018398:Homeodomain Proteins; D008297:Male; D051379:Mice; D008818:Mice, Neurologic Mutants; D009457:Neuroglia / Q000166:cytology / Q000502:physiology*; D009474:Neurons / Q000166:cytology / Q000502:physiology*; D009836:Oligodendroglia / Q000166:cytology / Q000502:physiology; D009924:Organ Culture Techniques; D000071841:PAX6 Transcription Factor; D051761:Paired Box Transcription Factors; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D012097:Repressor Proteins; D013116:Spinal Cord / Q000166:cytology / Q000196:embryology*; D013234:Stem Cells / Q000502:physiology*
chemical_list: D004268:DNA-Binding Proteins; D005136:Eye Proteins; D018398:Homeodomain Proteins; D000071841:PAX6 Transcription Factor; D051761:Paired Box Transcription Factors; C000605732:Pax6 protein, mouse; D012097:Repressor Proteins