Kainate receptor post-translational modifications differentially regulate association with 4.1N to control activity-dependent receptor endocytosis

J Biol Chem. 2013 Mar 29;288(13):8952-65. doi: 10.1074/jbc.M112.440719. Epub 2013 Feb 11.

Abstract

Kainate receptors exhibit a highly compartmentalized distribution within the brain; however, the molecular and cellular mechanisms that coordinate their expression at neuronal sites of action are poorly characterized. Here we report that the GluK1 and GluK2 kainate receptor subunits interact with the spectrin-actin binding scaffolding protein 4.1N through a membrane-proximal domain in the C-terminal tail. We found that this interaction is important for the forward trafficking of GluK2a receptors, their distribution in the neuronal plasma membrane, and regulation of receptor endocytosis. The association between GluK2a receptors and 4.1N was regulated by both palmitoylation and protein kinase C (PKC) phosphorylation of the receptor subunit. Palmitoylation of the GluK2a subunit promoted 4.1N association, and palmitoylation-deficient receptors exhibited reduced neuronal surface expression and compromised endocytosis. Conversely, PKC activation decreased 4.1N interaction with GluK2/3-containing kainate receptors in acute brain slices, an effect that was reversed after inhibition of PKC. Our data and previous studies therefore demonstrate that these two post-translational modifications have opposing effects on 4.1N association with GluK2 kainate and GluA1 AMPA receptors. The convergence of the signaling pathways regulating 4.1N protein association could thus result in the selective removal of AMPA receptors from the plasma membrane while simultaneously promoting the insertion and stabilization of kainate receptors, which may be important for tuning neuronal excitability and synaptic plasticity.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • COS Cells
  • Cell Membrane / metabolism
  • Chlorocebus aethiops
  • Cytoskeletal Proteins / metabolism*
  • Cytoskeleton / metabolism
  • Endocytosis / physiology*
  • GluK2 Kainate Receptor
  • HEK293 Cells
  • Humans
  • Membrane Proteins / metabolism*
  • Neurons / metabolism
  • Neuropeptides / metabolism*
  • Palmitic Acid / chemistry
  • Phosphorylation
  • Protein Binding
  • Protein Processing, Post-Translational*
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, AMPA / metabolism
  • Receptors, Kainic Acid / metabolism*
  • Recombinant Proteins / chemistry
  • Signal Transduction
  • Synapses / metabolism

Substances

  • Cytoskeletal Proteins
  • Membrane Proteins
  • Neuropeptides
  • Receptors, AMPA
  • Receptors, Kainic Acid
  • Recombinant Proteins
  • erythrocyte membrane protein band 4.1-like 1
  • Palmitic Acid