1. Academic Validation
  2. Palmitoylation of gephyrin controls receptor clustering and plasticity of GABAergic synapses

Palmitoylation of gephyrin controls receptor clustering and plasticity of GABAergic synapses

  • PLoS Biol. 2014 Jul 15;12(7):e1001908. doi: 10.1371/journal.pbio.1001908.
Borislav Dejanovic 1 Marcus Semtner 2 Silvia Ebert 1 Tobias Lamkemeyer 3 Franziska Neuser 1 Bernhard Lüscher 4 Jochen C Meier 2 Guenter Schwarz 5
Affiliations

Affiliations

  • 1 Institute of Biochemistry, Department of Chemistry, University of Cologne, Cologne, Germany.
  • 2 RNA Editing and Hyperexcitability Disorders Helmholtz Group, Max Delbrück Center for Molecular Medicine, Berlin, Germany.
  • 3 Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany.
  • 4 Department of Biology and Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America.
  • 5 Institute of Biochemistry, Department of Chemistry, University of Cologne, Cologne, Germany; Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany.
Abstract

Postsynaptic scaffolding proteins regulate coordinated neurotransmission by anchoring and clustering receptors and adhesion molecules. Gephyrin is the major instructive molecule at inhibitory synapses, where it clusters glycine as well as major subsets of GABA type A receptors (GABAARs). Here, we identified palmitoylation of gephyrin as an important mechanism of strengthening GABAergic synaptic transmission, which is regulated by GABAAR activity. We mapped palmitoylation to Cys212 and Cys284, which are critical for both association of gephyrin with the postsynaptic membrane and gephyrin clustering. We identified DHHC-12 as the principal palmitoyl Acyltransferase that palmitoylates gephyrin. Furthermore, gephyrin pamitoylation potentiated GABAergic synaptic transmission, as evidenced by an increased amplitude of miniature inhibitory postsynaptic currents. Consistently, inhibiting gephyrin palmitoylation either pharmacologically or by expression of palmitoylation-deficient gephyrin reduced the gephyrin cluster size. In aggregate, our study reveals that palmitoylation of gephyrin by DHHC-12 contributes to dynamic and functional modulation of GABAergic synapses.

Figures