title: KCC2 knockdown impairs glycinergic synapse maturation in cultured spinal cord neurons.
abstract: Synaptic inhibition in the spinal cord is mediated mainly by strychnine-sensitive glycine (GlyRs) and by γ-aminobutyric acid type A receptors (GABAAR). During neuronal maturation, neonatal GlyRs containing α2 subunits are replaced by adult-type GlyRs harboring α1 and α3 subunits. At the same time period of postnatal development, the transmembrane chloride gradient is changed due to increased expression of the potassium-chloride cotransporter (KCC2), thereby shifting the GABA- and glycine-mediated synaptic currents from mostly excitatory depolarization to inhibitory hyperpolarization. Here, we used RNA interference to suppress KCC2 expression during in vitro maturation of spinal cord neurons. Morphological analysis revealed reduced numbers and size of dendritic GlyR clusters containing α1 subunits but not of clusters harboring neonatal α2 subunits. The morphological changes were accompanied by decreased frequencies and amplitudes of glycinergic miniature inhibitory currents, whereas GABAergic synapses appeared functionally unaltered. Our data indicate that KCC2 exerts specific functions for the maturation of glycinergic synapses in cultured spinal cord neurons.
authors.affiliation: Institute for Physiology and Pathophysiology, University of Heidelberg, INF 326, 69120, Heidelberg, Germany.
authors.forename: Chrysovalandis
authors.initials: C
authors.lastname: Schwale
authors.affiliation: Institute for Anatomy and Cell Biology, University of Heidelberg, INF 307, 69120, Heidelberg, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Schumacher
authors.affiliation: Institute for Physiology and Pathophysiology, University of Heidelberg, INF 326, 69120, Heidelberg, Germany.
authors.forename: Claus
authors.initials: C
authors.lastname: Bruehl
authors.affiliation: Institute for Physiology and Pathophysiology, University of Heidelberg, INF 326, 69120, Heidelberg, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Titz
authors.affiliation: Institute for Anatomy and Cell Biology, University of Heidelberg, INF 307, 69120, Heidelberg, Germany.
authors.forename: Andrea
authors.initials: A
authors.lastname: Schlicksupp
authors.affiliation: Institute for Anatomy and Cell Biology, University of Heidelberg, INF 307, 69120, Heidelberg, Germany.
authors.forename: Mirka
authors.initials: M
authors.lastname: Kokocinska
authors.affiliation: Institute for Anatomy and Cell Biology, University of Heidelberg, INF 307, 69120, Heidelberg, Germany.
authors.forename: Joachim
authors.initials: J
authors.lastname: Kirsch
authors.affiliation: Institute for Physiology and Pathophysiology, University of Heidelberg, INF 326, 69120, Heidelberg, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Draguhn
authors.affiliation: Institute for Anatomy and Cell Biology, University of Heidelberg, INF 307, 69120, Heidelberg, Germany. jochen.kuhse@urz.uni-heidelberg.de.
authors.forename: Jochen
authors.initials: J
authors.lastname: Kuhse
mesh_terms: D002478:Cells, Cultured; D005998:Glycine / Q000378:metabolism*; D006801:Humans; D009474:Neurons / Q000166:cytology* / Q000378:metabolism*; D013116:Spinal Cord / Q000166:cytology*; D027981:Symporters / Q000172:deficiency* / Q000378:metabolism*; D013569:Synapses / Q000378:metabolism*; D000096922:K Cl- Cotransporters
chemical_list: D005998:Glycine; D027981:Symporters; C000606816:SLC12A5 protein, human; D000096922:K Cl- Cotransporters
keywords: GABAR; Gephyrin; GlyR; KCC2; Synaptogenesis