title: Overexpression of adhesion molecule L1 in NG108-15 neuroblastoma X glioma hybrid cells enhances dibutyryl cyclic AMP-induced neurite outgrowth and functional synapse formation with myotubes.
abstract: The role of adhesion molecule L1 in synapse formation was examined by transient transfection of L1 cDNA in neuroblastoma x glioma hybrid NG108-15 cells. L1 overexpression was found in approximately 50% of the transfected NG108-15 cell population. Neurite outgrowth induced by 0.25 mM dibutyryl cyclic AMP (cAMP) was much greater in L1-transfected NG108-15 cells than that in nontransfected and mock-transfected cells. The proportion of cells with neurites and the number of neurites per cells were increased in L1-transfected cells after 2 days of dibutyryl cAMP treatment. The proportion of cells with branched neurites and the average length of neurites were higher at day 4. A significantly higher rate of synapse formation with myotubes was apparent in the late phase of coculture (days 4-7) in L1-transfected cells than in control cells. The miniature end-plate potential frequency in myotubes was the same for the three types of NG108-15 cells. These results show that overexpression of L1 in NG108-15 cells facilitates synaptic connections by enhancing branching and elongation of neurites induced with dibutyryl cAMP, rather than by increasing probability of acetylcholine release.
authors.affiliation: Department of Biophysics, Neuroinformation Research Institute, Kanazawa University School of Medicine, Takara-machi, Japan.
authors.forename: Z G
authors.initials: ZG
authors.lastname: Zhong
authors.forename: S
authors.initials: S
authors.lastname: Yokoyama
authors.forename: M
authors.initials: M
authors.lastname: Noda
authors.forename: H
authors.initials: H
authors.lastname: Higashida
mesh_terms: D000818:Animals; D003994:Bucladesine / Q000494:pharmacology*; D015816:Cell Adhesion Molecules, Neuronal / Q000235:genetics; D002454:Cell Differentiation / Q000502:physiology; D018507:Gene Expression Regulation, Developmental / Q000502:physiology; D005910:Glioma; D006822:Hybrid Cells / Q000166:cytology / Q000502:physiology / Q000648:ultrastructure; D015151:Immunoblotting; D007150:Immunohistochemistry; D039841:Leukocyte L1 Antigen Complex; D008562:Membrane Glycoproteins / Q000235:genetics*; D051379:Mice; D018485:Muscle Fibers, Skeletal / Q000166:cytology / Q000502:physiology* / Q000648:ultrastructure; D016501:Neurites / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D009447:Neuroblastoma; D009469:Neuromuscular Junction / Q000737:chemistry / Q000187:drug effects / Q000502:physiology; D051381:Rats; D013569:Synapses / Q000187:drug effects / Q000502:physiology*; D014162:Transfection
chemical_list: D015816:Cell Adhesion Molecules, Neuronal; D039841:Leukocyte L1 Antigen Complex; D008562:Membrane Glycoproteins; D003994:Bucladesine