title: Cochleovestibular nerve development is integrated with migratory neural crest cells.
abstract: The cochleovestibular (CV) nerve, which connects the inner ear to the brain, is the nerve that enables the senses of hearing and balance. The aim of this study was to document the morphological development of the mouse CV nerve with respect to the two embryonic cells types that produce it, specifically, the otic vesicle-derived progenitors that give rise to neurons, and the neural crest cell (NCC) progenitors that give rise to glia. Otic tissues of mouse embryos carrying NCC lineage reporter transgenes were whole mount immunostained to identify neurons and NCC. Serial optical sections were collected by confocal microscopy and were compiled to render the three dimensional (3D) structure of the developing CV nerve. Spatial organization of the NCC and developing neurons suggest that neuronal and glial populations of the CV nerve develop in tandem from early stages of nerve formation. NCC form a sheath surrounding the CV ganglia and central axons. NCC are also closely associated with neurites projecting peripherally during formation of the vestibular and cochlear nerves. Physical ablation of NCC in chick embryos demonstrates that survival or regeneration of even a few individual NCC from ectopic positions in the hindbrain results in central projection of axons precisely following ectopic pathways made by regenerating NCC.
authors.affiliation: University of Louisville, Department of Molecular, Cellular and Craniofacial Biology, Louisville, KY 40201, USA. Electronic address: Lisa.Sandell@Louisville.edu.
authors.forename: Lisa L
authors.initials: LL
authors.lastname: Sandell
authors.affiliation: Stowers Institute for Medical Research, Kansas City, MO 64110, USA; Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS 66160, USA.
authors.forename: Naomi E
authors.initials: NE
authors.lastname: Butler Tjaden
authors.affiliation: Department of Surgery, University of Wisconsin, Madison, WI 53792, USA.
authors.forename: Amanda J
authors.initials: AJ
authors.lastname: Barlow
authors.affiliation: Stowers Institute for Medical Research, Kansas City, MO 64110, USA; Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS 66160, USA.
authors.forename: Paul A
authors.initials: PA
authors.lastname: Trainor
mesh_terms: D000818:Animals; D002642:Chick Embryo; D003056:Cochlear Nerve / Q000196:embryology*; D004423:Ear / Q000196:embryology; D051379:Mice; D018613:Microscopy, Confocal; D009432:Neural Crest / Q000166:cytology*; D016501:Neurites; D014725:Vestibular Nerve / Q000196:embryology*
keywords: 3-dimensional; 3D; Axon; CV; Cochlea; Craniofacial; E; Ear; GFP; Green Fluorescent Protein; NCC; Neural crest; Neuron; Otic; P; R; Vestibular; cochleovestibular; embryonic day; neural crest cells; postnatal day; rhombomere