Activity-dependent subcellular cotrafficking of the small GTPase Rem2 and Ca2+/CaM-dependent protein kinase IIα

Robyn Flynn1, Etienne Labrie-Dion, Nikolas Bernier

  • 1Department of Physiology and Pharmacology, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.

Plos One
|July 21, 2012
PubMed
Abstract

Insights

Rem2 protein translocates in neurons upon activity, binding to CaM and CaMKII. This suggests Rem2 plays a role in neuronal plasticity through co-trafficking with CaMKII.

Area of Science:

  • Neuroscience
  • Molecular Biology
  • Cell Biology

Background:

  • Rem2 is a brain-predominant RGK family GTP-binding protein.
  • Known functions include calcium channel modulation and cytoskeletal changes.
  • Rem2 is implicated in synaptic development.

Purpose of the Study:

  • Investigate the effect of neuronal activity on Rem2 subcellular distribution.
  • Identify Rem2 interacting partners and their relationship to activity-dependent changes.

Main Methods:

  • Utilized rat hippocampal neurons and HEK cells.
  • Analyzed activity- and N-Methyl-D-Aspartate Receptor (NMDAR)-dependent translocation.
  • Studied Ca(2+) influx, calmodulin (CaM) binding, and CaMKII interactions.

Main Results:

  • Rem2 exhibits activity- and NMDAR-dependent redistribution.
  • Translocation depends on Ca(2+) influx, CaM binding, and an auto-inhibitory domain.
  • Rem2 binds Ca(2+)/CaM-dependent protein kinase IIα (CaMKII) in a Ca(2+)/CaM-dependent manner.
  • Observed co-clustering and co-trafficking of Rem2 and CaMKII.
  • Inhibition of CaMKII aggregation reduced Rem2 clustering.

Conclusions:

  • Rem2 functions in co-trafficking with CaMKII.
  • Suggests a novel role for Rem2 in neuronal plasticity.

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