Journal article
A disorganized innervation of the inner ear persists in the absence of ErbB2
Brain research, Vol.1091(1), pp.186-199
2006
DOI: 10.1016/j.brainres.2006.02.090
PMCID: PMC3075922
PMID: 16630588
Abstract
ErbB2 protein is essential for the development of Schwann cells and for the normal fiber growth and myelin formation of peripheral nerves. We have investigated the fate of the otocyst-derived inner ear sensory neurons in the absence of ErbB2 using\nErbB2 null mutants. Afferent innervation of the ear sensory epithelia shows numerous fibers overshooting the organ of Corti, followed by a reduction of those fibers in near term embryos. This suggests that mature Schwann cells do not play a role in targeting or maintaining the inner ear innervation. Comparable to the overshooting of nerve fibers, sensory neurons migrate beyond their normal locations into unusual positions in the modiolus. They may miss a stop signal provided by the Schwann cells that are absent as revealed with detailed histology. Reduction of overshooting afferents may be enhanced by a reduction of the neurotrophin\nNtf3 transcript to about 25% of wild type.\nNtf3 transcript reductions are comparable to an adult model that uses a dominant negative form of\nErbB4 expressed in the supporting cells and Schwann cells of the organ of Corti.\nErbB2 null mice retain afferents to inner hair cells possibly because of the prominent expression of the neurotrophin\nBdnf in developing hair cells. Despite the normal presence of\nBdnf transcript, afferent fibers are disoriented near the organ of Corti. Efferent fibers do not form an intraganglionic spiral bundle in the absence of spiral ganglia and appear reduced and disorganized. This suggests that either ErbB2 mediated alterations in sensory neurons or the absence of Schwann cells affects efferent fiber growth to the organ of Corti.
Details
- Title: Subtitle
- A disorganized innervation of the inner ear persists in the absence of ErbB2
- Creators
- Jacqueline K Morris - Department of Biology and Geology, Baldwin-Wallace College, Berea, OH 44017, USAAdel Maklad - Department of Anatomy, University of Mississippi Medical Center, Jackson, MS, USALaura A Hansen - Department of Biomedical Sciences, Creighton University, Omaha, NE 68178, USAFeng Feng - Department of Biomedical Sciences, Creighton University, Omaha, NE 68178, USAChristian Sorensen - Department of Biomedical Sciences, Creighton University, Omaha, NE 68178, USAKuo-Fen Lee - Peptide Biology Laboratories, The Salk Institute for Biological Sciences, La Jolla, CA 92037, USAWendy B Macklin - Department of Neurosciences, Cleveland Clinic Foundation, Cleveland, OH 44195, USABernd Fritzsch - Department of Biomedical Sciences, Creighton University, Omaha, NE 68178, USA
- Resource Type
- Journal article
- Publication Details
- Brain research, Vol.1091(1), pp.186-199
- DOI
- 10.1016/j.brainres.2006.02.090
- PMID
- 16630588
- PMCID
- PMC3075922
- NLM abbreviation
- Brain Res
- ISSN
- 0006-8993
- eISSN
- 1872-6240
- Publisher
- Elsevier B.V
- Language
- English
- Date published
- 2006
- Academic Unit
- Iowa Neuroscience Institute; Biology; Craniofacial Anomalies Research Center
- Record Identifier
- 9984070221702771
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