title: In vivo clonal overexpression of neuroligin 3 and neuroligin 2 in neurons of the rat cerebral cortex: Differential effects on GABAergic synapses and neuronal migration.
abstract: We studied the effect of clonal overexpression of neuroligin 3 (NL3) or neuroligin 2 (NL2) in the adult rat cerebral cortex following in utero electroporation (IUEP) at embryonic stage E14. Overexpression of NL3 leads to a large increase in vesicular gamma-aminobutyric acid (GABA) transporter (vGAT) and glutamic acid decarboxylase (GAD)65 in the GABAergic contacts that the overexpressing neurons receive. Overexpression of NL2 produced a similar effect but to a lesser extent. In contrast, overexpression of NL3 or NL2 after IUEP does not affect vesicular glutamate transporter 1 (vGlut1) in the glutamatergic contacts that the NL3 or NL2-overexpressing neurons receive. The NL3 or NL2-overexpressing neurons do not show increased innervation by parvalbumin-containing GABAergic terminals or increased parvalbumin in the same terminals that show increased vGAT. These results indicate that the observed increase in vGAT and GAD65 is not due to increased GABAergic innervation but to increased expression of vGAT and GAD65 in the GABAergic contacts that NL3 or NL2-overexpressing neurons receive. The majority of bright vGAT puncta contacting the NL3-overexpressing neurons have no gephyrin juxtaposed to them, indicating that many of these contacts are nonsynaptic. This contrasts with the majority of the NL2-overexpressing neurons, which show plenty of synaptic gephyrin clusters juxtaposed to vGAT. Besides having an effect on GABAergic contacts, overexpression of NL3 interferes with the neuronal radial migration, in the cerebral cortex, of the neurons overexpressing NL3.
authors.affiliation: Department of Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut, 06269.
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Fekete
authors.forename: Tzu-Ting
authors.initials: TT
authors.lastname: Chiou
authors.forename: Celia P
authors.initials: CP
authors.lastname: Miralles
authors.forename: Rachel S
authors.initials: RS
authors.lastname: Harris
authors.forename: Christopher G
authors.initials: CG
authors.lastname: Fiondella
authors.forename: Joseph J
authors.initials: JJ
authors.lastname: Loturco
authors.forename: Angel L
authors.initials: AL
authors.lastname: De Blas
mesh_terms: D000276:Adjuvants, Immunologic; D000818:Animals; D015816:Cell Adhesion Molecules, Neuronal / Q000235:genetics / Q000378:metabolism*; D002465:Cell Movement / Q000502:physiology*; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000378:metabolism*; D018274:Electroporation; D005968:Glutamate Decarboxylase / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D009474:Neurons / Q000378:metabolism*; D010320:Parvalbumins / Q000378:metabolism; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D013569:Synapses / Q000378:metabolism; D014162:Transfection; D050598:Vesicular Glutamate Transport Protein 1 / Q000378:metabolism; D050495:Vesicular Inhibitory Amino Acid Transport Proteins / Q000378:metabolism; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
chemical_list: D000276:Adjuvants, Immunologic; D015816:Cell Adhesion Molecules, Neuronal; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D010320:Parvalbumins; C493466:Slc17a7 protein, rat; C118623:Slc32a1 protein, rat; D050598:Vesicular Glutamate Transport Protein 1; D050495:Vesicular Inhibitory Amino Acid Transport Proteins; C098003:neuroligin 2; C098004:neuroligin 3; D005680:gamma-Aminobutyric Acid; D005968:Glutamate Decarboxylase
keywords: gephyrin; glutamic acid decarboxylase; in utero electroporation; neuronal migration; synapse formation; vesicular GABA transporter