NSF interaction is important for direct insertion of GluR2 at synaptic sites.
Here, we use a cell surface thrombin cleavage assay to investigate directly the role of NSF in the surface delivery and synaptic accumulation of alpha-amino-3-hydroxy-5-methylisoxazolepropionate (AMPA) receptors. In cultured hippocampal neurons, the GluR2 subunit (which specifically interacts with NSF) inserts rapidly into the plasma membrane from intracellular compartments and accumulates in synaptic sites. In contrast, surface accumulation of GluR3 (a subunit that does not interact with NSF) or a GluR2 mutant defective in NSF binding (DeltaA849-Q853) occurs initially at extrasynaptic sites and is kinetically slower than wild-type GluR2. Introducing a binding site for NSF into GluR3 (GluR3NSF) generates a subunit that behaves like GluR2 in terms of kinetics and site of surface insertion. These data suggest that the NSF interaction is necessary for rapid incorporation of AMPA receptor subunits into synapses and is sufficient to confer this property on GluR3.
Beretta
Francesca
F
DTI Dulbecco Telethon Institute, CNR Institute of Neuroscience, Cellular and Molecular Pharmacology, Department of Pharmacology, University of Milano, Via Vanvitelli, 32, Milano, MI 2019, Italy.
Sala
Carlo
C
Saglietti
Laura
L
Hirling
Harald
H
Sheng
Morgan
M
Passafaro
Maria
M
D000818:Animals; D001665:Binding Sites / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D005998:Glycine / Q000378:metabolism / Q000494:pharmacology; D006624:Hippocampus / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism; D052066:N-Ethylmaleimide-Sensitive Proteins; D016202:N-Methylaspartate / Q000378:metabolism / Q000494:pharmacology; D051381:Rats; D018091:Receptors, AMPA / Q000032:analysis / Q000378:metabolism*; D013569:Synapses / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D033921:Vesicular Transport Proteins / Q000032:analysis / Q000378:metabolism*
D018091:Receptors, AMPA; D033921:Vesicular Transport Proteins; D016202:N-Methylaspartate; D052066:N-Ethylmaleimide-Sensitive Proteins; C498737:Nsf protein, rat; C104722:glutamate receptor ionotropic, AMPA 2; D005998:Glycine