title: Neural cell adhesion molecule NrCAM is expressed in the mammalian inner ear and modulates spiral ganglion neurite outgrowth in an in vitro alternate choice assay.
abstract: Neuron-glial-related cell adhesion molecule (NrCAM) is a neuronal cell adhesion molecule involved in neuron-neuron and neuron-glial adhesion as well as directional signaling during axonal cone growth. NrCAM has been shown to be involved in several cellular processes in the central and peripheral nervous systems, including neurite outgrowth, axonal pathfinding and myelination, fasciculation of nerve fibers, and cell migration. This includes sensory systems such as the eye and olfactory system. However, there are no reports on the expression/function of NrCAM in the auditory system. The aim of the present study was to elucidate the occurrence of NrCAM in the mammalian cochlea and its role in innervation of the auditory end organ. Our work indicates that NrCAM is highly expressed in the developing mammalian cochlea (position consistent with innervation). Moreover, we found that NrCAM, presented in stripe micropatterns, provide directional cues to neonatal rat inner ear spiral ganglion neurites in vitro. Our results are consistent with a role for NrCAM in the pathfinding of spiral ganglion dendrites toward their hair cell targets in the sensory epithelium.
authors.affiliation: Department of Surgery/Otolaryngology, UCSD School of Medicine, 9500 Gilman Drive, MC0666, La Jolla, CA, 92093, USA.
authors.forename: Yves
authors.initials: Y
authors.lastname: Brand
authors.forename: Michael
authors.initials: M
authors.lastname: Sung
authors.forename: Kwang
authors.initials: K
authors.lastname: Pak
authors.forename: Eduardo
authors.initials: E
authors.lastname: Chavez
authors.forename: Eric
authors.initials: E
authors.lastname: Wei
authors.forename: Vesna
authors.initials: V
authors.lastname: Radojevic
authors.forename: Daniel
authors.initials: D
authors.lastname: Bodmer
authors.forename: Allen F
authors.initials: AF
authors.lastname: Ryan
mesh_terms: D000818:Animals; D015815:Cell Adhesion Molecules / Q000235:genetics / Q000378:metabolism*; D002478:Cells, Cultured; D003051:Cochlea / Q000254:growth & development / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D016501:Neurites / Q000378:metabolism / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013136:Spiral Ganglion / Q000166:cytology / Q000254:growth & development / Q000378:metabolism*
chemical_list: D015815:Cell Adhesion Molecules