title: Radial glia inhibit peripheral glial infiltration into the spinal cord at motor exit point transition zones.
abstract: In the mature vertebrate nervous system, central and peripheral nervous system (CNS and PNS, respectively) GLIA myelinate distinct motor axon domains at the motor exit point transition zone (MEP TZ). How these cells preferentially associate with and myelinate discrete, non-overlapping CNS versus PNS axonal segments, is unknown. Using in vivo imaging and genetic cell ablation in zebrafish, we demonstrate that radial glia restrict migration of PNS glia into the spinal cord during development. Prior to development of radial glial endfeet, peripheral cells freely migrate back and forth across the MEP TZ. However, upon maturation, peripherally located cells never enter the CNS. When we ablate radial glia, peripheral glia ectopically migrate into the spinal cord during developmental stages when they would normally be restricted. These findings demonstrate that radial glia contribute to both CNS and PNS development and control the unidirectional movement of glial cell types across the MEP TZ early in development. GLIA 2016. GLIA 2016;64:1138-1153.
authors.affiliation: Department of Biology, University of Virginia, Charlottesville, Virginia, 22904.
authors.forename: Cody J
authors.initials: CJ
authors.lastname: Smith
authors.affiliation: Department of Biological Sciences, Smith College, Northampton, Massachusetts, 01003.
authors.forename: Kimberly
authors.initials: K
authors.lastname: Johnson
authors.affiliation: Department of Biology, University of Virginia, Charlottesville, Virginia, 22904.|Neuroscience Graduate Program, University of Virginia, Charlottesville, Virginia, 22904.
authors.forename: Taylor G
authors.initials: TG
authors.lastname: Welsh
authors.affiliation: Department of Biological Sciences, Smith College, Northampton, Massachusetts, 01003.|Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst, Massachusetts, 01003.
authors.forename: Michael J F
authors.initials: MJ
authors.lastname: Barresi
authors.affiliation: Department of Biology, University of Virginia, Charlottesville, Virginia, 22904.|Neuroscience Graduate Program, University of Virginia, Charlottesville, Virginia, 22904.
authors.forename: Sarah
authors.initials: S
authors.lastname: Kucenas
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D002465:Cell Movement / Q000502:physiology*; D004625:Embryo, Nonmammalian; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D009046:Motor Neurons / Q000502:physiology / Q000648:ultrastructure; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism; D009420:Nervous System / Q000166:cytology* / Q000196:embryology; D009457:Neuroglia / Q000502:physiology* / Q000648:ultrastructure; D013116:Spinal Cord / Q000166:cytology* / Q000196:embryology; D015027:Zebrafish; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D008164:Luminescent Proteins; D009419:Nerve Tissue Proteins; D029961:Zebrafish Proteins
keywords: CNS/PNS transition zone; motor exit point glia; neural crest cells; radial glia; zebrafish