title: Neuroglycan C, a neural tissue-specific transmembrane chondroitin sulfate proteoglycan, in retinal neural network formation.
abstract: OBJECTIVE
  Neuroglycan C (NGC) is a transmembrane chondroitin sulfate proteoglycan present exclusively in central nervous system tissues. In the current study the expression pattern and characterization of NGC during the development of the retina were investigated.
  
  
  METHODS
  Expressional changes of NGC mRNAs during rat retinal development were examined by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR). The localization and characterization of NGC core proteins were investigated by immunoblot analysis and immunohistochemistry using an anti-NGC antibody.
  
  
  RESULTS
  Immunohistochemical analysis revealed that NGC was highly expressed in the nerve fiber layer (NFL) and inner plexiform layer (IPL) in rat postnatal developing retina. At embryonal stages, NGC immunoreactivities were faint. In contrast, at postnatal developmental stages (approximately postnatal day [P]7), intense immunoreactivity was observed in the NFL and IPL, where active dendrite branching was observed, and conventional synapses began to be formed. As retinal layer differentiation proceeded (from P14 to P42), immunoreactivities in the inner retinal layers gradually became fainter. Immunoblot and semiquantitative RT-PCR analyses showed that the peak level of NGC expression occurred on approximately P7 and P14. Glycosylation of the NGC core protein changed as the retinal layers matured. In immunoelectron microscopic analysis, NGC immunoreactivity was located on the axonal membranes of neuronal cells in the postnatal retina, whereas immunoreactivity was reduced on membranes at the adult stage. In retinal ganglion cells in vitro, NGC was highly localized in their spiny budding neurites.
  
  
  CONCLUSIONS
  The results show spatiotemporal expression patterns of NGC, and suggest that it plays a role in the formation of neural networks in retinal development.
authors.affiliation: Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Tenri Hospital, Osaka, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Inatani
authors.forename: H
authors.initials: H
authors.lastname: Tanihara
authors.forename: A
authors.initials: A
authors.lastname: Oohira
authors.forename: Y
authors.initials: Y
authors.lastname: Otori
authors.forename: A
authors.initials: A
authors.lastname: Nishida
authors.forename: M
authors.initials: M
authors.lastname: Honjo
authors.forename: N
authors.initials: N
authors.lastname: Kido
authors.forename: Y
authors.initials: Y
authors.lastname: Honda
mesh_terms: D000818:Animals; D001369:Axons / Q000378:metabolism; D015139:Blotting, Southern; D002462:Cell Membrane / Q000378:metabolism; D002478:Cells, Cultured; D005136:Eye Proteins / Q000096:biosynthesis / Q000235:genetics*; D015870:Gene Expression; D015151:Immunoblotting; D007124:Immunoenzyme Techniques; D008565:Membrane Proteins / Q000096:biosynthesis / Q000235:genetics*; D016253:Microscopy, Immunoelectron; D009415:Nerve Net / Q000166:cytology* / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000096:biosynthesis / Q000235:genetics*; D011509:Proteoglycans / Q000096:biosynthesis / Q000235:genetics*; D012333:RNA, Messenger / Q000096:biosynthesis*; D051381:Rats; D017208:Rats, Wistar; D012160:Retina / Q000254:growth & development* / Q000378:metabolism / Q000648:ultrastructure; D012165:Retinal Ganglion Cells / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: C485738:Cspg5 protein, rat; D005136:Eye Proteins; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D011509:Proteoglycans; D012333:RNA, Messenger