Department of Brain Cognitive Sciences, Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Building 46, Cambridge, MA 02139, U.S.A.
Trafficking and synaptic anchoring of ionotropic inhibitory neurotransmitter receptors
Version of Record online: 9 JAN 2012
2007 Société Française des Microscopies and Société Biologie Cellulaire de France
Biology of the Cell
Volume 99, Issue 6, pages 297–309, June 2007
How to Cite
Kneussel, M. and Loebrich, S. (2007), Trafficking and synaptic anchoring of ionotropic inhibitory neurotransmitter receptors. Biology of the Cell, 99: 297–309. doi: 10.1042/BC20060120
- Issue online: 9 JAN 2012
- Version of Record online: 9 JAN 2012
- Received 24 November 2006; Accepted 10 January 2007
- γ-aminobutyric type A receptor (GABAAR);
- glycine receptor;
Neurotransmitter receptors are subject to microtubule-based transport between intracellular organelles and the neuronal plasma membrane. Receptors that arrive at plasma membrane compartments diffuse laterally within the plane of the cellular surface. To achieve immobilization at their sites of action, cytoplasmic receptor residues bind to submembrane proteins, which are coupled to the underlying cytoskeleton by multiprotein scaffolds. GABAARs (γ-aminobutyric type A receptors) and GlyRs (glycine receptors) are the major inhibitory receptors in the central nervous system. At inhibitory postsynaptic sites, all GlyRs and the majority of GABAARs directly or indirectly couple to gephyrin, a multimeric PSD (postsynaptic density) component. In addition to cluster formations at axo-dendritic contacts, individual GABAAR subtypes also anchor and concentrate at extrasynaptic positions, either through association with gephyrin or direct interaction with the ERM (ezrin/radixin/moesin) family protein radixin. In addition to their role in diffusion trapping of surface receptors, scaffold components also undergo rapid exchange to/from and between postsynaptic specializations, leading to a dynamic equilibrium of receptor—scaffold complexes. Moreover, scaffold components serve as adaptor proteins that mediate specificity in intracellular transport complexes. In the present review, we discuss the dynamic delivery, stabilization and removal of inhibitory receptors at synaptic sites.