Journal of Cell Science, Vol 113, Issue 15 2783-2795, Copyright © 2000 by Company of Biologists

JOURNAL ARTICLES

Formation of glycine receptor clusters and their accumulation at synapses

J Meier, C Meunier-Durmort, C Forest, A Triller and C Vannier
Laboratoire de Biologie Cellulaire de la Synapse Normale et Pathologique, INSERM U497, Ecole Normale Superieure, 75005 Paris, France.

The glycine receptor is highly enriched in microdomains of the postsynaptic neuronal surface apposed to glycinergic afferent endings. There is substantial evidence suggesting that the selective clustering of glycine receptor at these sites is mediated by the cytoplasmic protein gephyrin. To investigate the formation of postsynaptic glycine receptor domains, we have examined the surface insertion of epitope-tagged receptor alpha subunits in cultured spinal cord neurons after gene transfer by polyethylenimine-adenofection. Expression studies were also carried out using the non-neuronal cell line COS-7. Immunofluorescence microscopy was performed using wild-type isoforms and an alpha mutant subunit bearing the gephyrin-binding motif of the beta subunit. In COS-7 cells, transfected glycine receptor alpha subunits had a diffuse surface distribution. Following cotransfection with gephyrin, only the mutant subunit formed cell surface clusters. In contrast, in neurons all subunits were able to form cell surface clusters after transfection. These clusters were not colocalized with detectable endogenous gephyrin, and the GlyR beta subunit could not be detected in transfected cells. Therefore, exogenous receptors were not assembled as heteromeric complexes. A quantitative analysis demonstrated that newly synthesized glycine receptor progressively populated endogenous gephyrin clusters, since association of both proteins increased as a function of time after the onset of receptor synthesis. This phenomenon was accelerated when glycine receptor contained the gephyrin-binding domain. Together with previous results, these data support a two-step model for glycinergic synaptogenesis whereby the gephyrin-independent formation of cell surface clusters precedes the gephyrin-mediated postsynaptic accumulation of clusters.

This article has been cited by other articles:

				M.-V. Ehrensperger, C. Hanus, C. Vannier, A. Triller, and M. Dahan Multiple Association States between Glycine Receptors and Gephyrin Identified by SPT Analysis Biophys. J., May 15, 2007; 92(10): 3706 - 3718. [Abstract] [Full Text] [PDF]

				C. Bedet, J. C. Bruusgaard, S. Vergo, L. Groth-Pedersen, S. Eimer, A. Triller, and C. Vannier Regulation of Gephyrin Assembly and Glycine Receptor Synaptic Stability J. Biol. Chem., October 6, 2006; 281(40): 30046 - 30056. [Abstract] [Full Text] [PDF]

				C. Hanus, M.-V. Ehrensperger, and A. Triller Activity-dependent movements of postsynaptic scaffolds at inhibitory synapses. J. Neurosci., April 26, 2006; 26(17): 4586 - 4595. [Abstract] [Full Text] [PDF]

				D. Gonzalez-Forero and F. J. Alvarez Differential Postnatal Maturation of GABAA, Glycine Receptor, and Mixed Synaptic Currents in Renshaw Cells and Ventral Spinal Interneurons J. Neurosci., February 23, 2005; 25(8): 2010 - 2023. [Abstract] [Full Text] [PDF]

				D. Gonzalez-Forero, A. M. Pastor, E. J. Geiman, B. Benitez-Temino, and F. J. Alvarez Regulation of Gephyrin Cluster Size and Inhibitory Synaptic Currents on Renshaw Cells by Motor Axon Excitatory Inputs J. Neurosci., January 12, 2005; 25(2): 417 - 429. [Abstract] [Full Text] [PDF]

				M. Eguchi, M. Eguchi-Ishimae, and M. Greaves The small oligomerization domain of gephyrin converts MLL to an oncogene Blood, May 15, 2004; 103(10): 3876 - 3882. [Abstract] [Full Text] [PDF]

				J. Meier and R. Grantyn A Gephyrin-Related Mechanism Restraining Glycine Receptor Anchoring at GABAergic Synapses J. Neurosci., February 11, 2004; 24(6): 1398 - 1405. [Abstract] [Full Text] [PDF]

				C. Hanus, C. Vannier, and A. Triller Intracellular Association of Glycine Receptor with Gephyrin Increases Its Plasma Membrane Accumulation Rate J. Neurosci., February 4, 2004; 24(5): 1119 - 1128. [Abstract] [Full Text] [PDF]

				B. van Zundert, F. J. Alvarez, J. C. Tapia, H. H. Yeh, E. Diaz, and L. G. Aguayo Developmental-Dependent Action of Microtubule Depolymerization on the Function and Structure of Synaptic Glycine Receptor Clusters in Spinal Neurons J Neurophysiol, February 1, 2004; 91(2): 1036 - 1049. [Abstract] [Full Text] [PDF]

				P. Legendre, E. Muller, C. I. Badiu, J. Meier, C. Vannier, and A. Triller Desensitization of Homomeric alpha 1 Glycine Receptor Increases with Receptor Density Mol. Pharmacol., October 1, 2002; 62(4): 817 - 827. [Abstract] [Full Text] [PDF]

				M. Rosenberg, J. Meier, A. Triller, and C. Vannier Dynamics of Glycine Receptor Insertion in the Neuronal Plasma Membrane J. Neurosci., July 15, 2001; 21(14): 5036 - 5044. [Abstract] [Full Text] [PDF]