AMPA receptor subunits define properties of state-dependent synaptic plasticity.
Many synapses undergo immediate and persistent activity-dependent changes in strength via processes that fall under the umbrella of synaptic plasticity. It is known that this type of synaptic plasticity exhibits an underlying state dependence; that is, as synapses change in strength they move into distinct 'states' that are defined by the mechanism and ability to undergo future plasticity. In this study, we have investigated the molecular mechanisms that underlie state-dependent synaptic plasticity. Using intracellular application of peptides that mimic the C-terminal tail sequences of GluR1 and GluR2 AMPA receptor subtypes, combined with paired recordings of minimal synaptic connections, we have shown that AMPA receptor subtypes present in the membrane at a given time confer some properties of plasticity states. These data show that during synaptic plasticity, AMPA receptor subtypes are differentially stabilized by postsynaptic density proteins in or out of the postsynaptic membrane, and this differential synaptic expression of different AMPA receptor subtypes defines distinct synaptic states.
Emond
Michelle R
MR
Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94305, USA.
Montgomery
Johanna M
JM
Huggins
Matthew L
ML
Hanson
Jesse E
JE
Mao
Lifang
L
Huganir
Richard L
RL
Madison
Daniel V
DV
D000818:Animals; D056654:CA3 Region, Hippocampal / Q000166:cytology / Q000502:physiology; D002352:Carrier Proteins / Q000096:biosynthesis / Q000235:genetics; D002478:Cells, Cultured; D004594:Electrophysiology; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D007150:Immunohistochemistry; D047908:Intracellular Signaling Peptides and Proteins; D008845:Microinjections; D009419:Nerve Tissue Proteins / Q000096:biosynthesis / Q000235:genetics; D009473:Neuronal Plasticity / Q000187:drug effects / Q000502:physiology*; D009479:Neuropeptides / Q000138:chemical synthesis / Q000494:pharmacology; D018408:Patch-Clamp Techniques; D017966:Pyramidal Cells / Q000187:drug effects / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D018091:Receptors, AMPA / Q000096:biosynthesis / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D013569:Synapses / Q000187:drug effects / Q000502:physiology*; D009435:Synaptic Transmission / Q000187:drug effects
D002352:Carrier Proteins; D047908:Intracellular Signaling Peptides and Proteins; D009419:Nerve Tissue Proteins; D009479:Neuropeptides; D018091:Receptors, AMPA; C491308:Grip1 protein, rat; C104722:glutamate receptor ionotropic, AMPA 2