Extracellular Interactions between GluR2 and N-Cadherin in Spine Regulation

Laura Saglietti, Caroline Dequidt, Kinga Kamieniarz, Marie-Claude Rousset, Pamela Valnegri, Olivier Thoumine, Francesca Beretta, Laurent Fagni, Daniel Choquet, Carlo Sala, Morgan Sheng, Maria Passafaro
Neuron. 2007-05-01; 54(3): 461-477
DOI: 10.1016/j.neuron.2007.04.012

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1. Neuron. 2007 May 3;54(3):461-77.

Extracellular interactions between GluR2 and N-cadherin in spine regulation.

Saglietti L(1), Dequidt C, Kamieniarz K, Rousset MC, Valnegri P, Thoumine O,
Beretta F, Fagni L, Choquet D, Sala C, Sheng M, Passafaro M.

Author information:
(1)DTI Dulbecco Telethon Institute, CNR Institute of Neuroscience, Cellular and
Molecular Pharmacology, Department of Pharmacology, University of Milan, Italy.

Via its extracellular N-terminal domain (NTD), the AMPA receptor subunit GluR2
promotes the formation and growth of dendritic spines in cultured hippocampal
neurons. Here we show that the first N-terminal 92 amino acids of the
extracellular domain are necessary and sufficient for GluR2’s spine-promoting
activity. Moreover, overexpression of this extracellular domain increases the
frequency of miniature excitatory postsynaptic currents (mEPSCs). Biochemically,
the NTD of GluR2 can interact directly with the cell adhesion molecule
N-cadherin, in cis or in trans. N-cadherin-coated beads recruit GluR2 on the
surface of hippocampal neurons, and N-cadherin immobilization decreases GluR2
lateral diffusion on the neuronal surface. RNAi knockdown of N-cadherin prevents
the enhancing effect of GluR2 on spine morphogenesis and mEPSC frequency. Our
data indicate that in hippocampal neurons N-cadherin and GluR2 form a synaptic
complex that stimulates presynaptic development and function as well as promoting
dendritic spine formation.

DOI: 10.1016/j.neuron.2007.04.012
PMID: 17481398 [Indexed for MEDLINE]

Auteurs Bordeaux Neurocampus