title: Expression of neurite outgrowth factor and gicerin during inner ear development and hair cell regeneration in the chick.
abstract: Several cell adhesion molecules are expressed in the developing inner ear. The present study focused on gicerin, a novel member of the immunoglobulin superfamily, in an attempt to improve our understanding of the development and regeneration of chick inner ear. Gicerin is known to homophilically interact with itself and to bind to neurite outgrowth factor (NOF). The data collected herein show that gicerin is highly expressed in auditory epithelium and acoustic ganglion during early embryogenesis. The immunoreactivity of gicerin in the auditory epithelium decreases more rapidly than that in the acoustic ganglion as the mature hair cells become distinguishable. At the post-hatch stage, the expression of gicerin is not observed. In contrast, NOF was expressed on the basement membranes around the auditory epithelium, and in the acoustic ganglion during development and after birth, but not in the auditory epithelium. Following noise damage, gicerin is transiently re-expressed on the damage receptor epithelium when active cell proliferation is observed in the epithelium. This positive reaction immediately disappears as immature short hair cells appear. These results suggest that gicerin may be associated with cell proliferation in the auditory epithelium, and play a role in neurite extension of the acoustic ganglion cells in conjunction with NOF.
authors.affiliation: Department of Otolaryngology, Osaka University Medical School, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Kajikawa
authors.forename: M
authors.initials: M
authors.lastname: Umemoto
authors.forename: E
authors.initials: E
authors.lastname: Taira
authors.forename: N
authors.initials: N
authors.lastname: Miki
authors.forename: Y
authors.initials: Y
authors.lastname: Mishiro
authors.forename: T
authors.initials: T
authors.lastname: Kubo
authors.forename: Y
authors.initials: Y
authors.lastname: Yoneda
mesh_terms: D000161:Acoustic Stimulation; D000818:Animals; D030161:Avian Proteins; D051929:CD146 Antigen; D002352:Carrier Proteins / Q000096:biosynthesis*; D015815:Cell Adhesion Molecules / Q000096:biosynthesis*; D002645:Chickens; D004847:Epithelial Cells / Q000737:chemistry; D006198:Hair Cells, Auditory / Q000254:growth & development* / Q000378:metabolism / Q000648:ultrastructure; D009414:Nerve Growth Factors / Q000096:biosynthesis*; D009416:Nerve Regeneration / Q000502:physiology*; D009419:Nerve Tissue Proteins / Q000096:biosynthesis; D016501:Neurites / Q000737:chemistry / Q000378:metabolism*; D009622:Noise; D000159:Vestibulocochlear Nerve / Q000378:metabolism / Q000503:physiopathology
chemical_list: D030161:Avian Proteins; D051929:CD146 Antigen; D002352:Carrier Proteins; D015815:Cell Adhesion Molecules; D009414:Nerve Growth Factors; D009419:Nerve Tissue Proteins; C086935:gicerin protein, Gallus gallus