Molecular constituents of neuronal AMPA receptors.
Dynamic regulation of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) underlies aspects of synaptic plasticity. Although numerous AMPAR-interacting proteins have been identified, their quantitative and relative contributions to native AMPAR complexes remain unclear. Here, we quantitated protein interactions with neuronal AMPARs by immunoprecipitation from brain extracts. We found that stargazin-like transmembrane AMPAR regulatory proteins (TARPs) copurified with neuronal AMPARs, but we found negligible binding to GRIP, PICK1, NSF, or SAP-97. To facilitate purification of neuronal AMPAR complexes, we generated a transgenic mouse expressing an epitope-tagged GluR2 subunit of AMPARs. Taking advantage of this powerful new tool, we isolated two populations of GluR2 containing AMPARs: an immature complex with the endoplasmic reticulum chaperone immunoglobulin-binding protein and a mature complex containing GluR1, TARPs, and PSD-95. These studies establish TARPs as the auxiliary components of neuronal AMPARs.
Fukata
Yuko
Y
Department of Physiology, University of California, San Francisco, San Francisco, CA 94143, USA.
Tzingounis
Anastassios V
AV
Trinidad
Jonathan C
JC
Fukata
Masaki
M
Burlingame
Alma L
AL
Nicoll
Roger A
RA
Bredt
David S
DS
D000818:Animals; D001921:Brain / Q000378:metabolism*; D015220:Calcium Channels / Q000378:metabolism; D002460:Cell Line; D000076122:Disks Large Homolog 4 Protein; D000091342:Endoplasmic Reticulum Chaperone BiP; D051528:Guanylate Kinases; D006360:Heat-Shock Proteins / Q000378:metabolism; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D008222:Lymphokines / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice; D008822:Mice, Transgenic; D018832:Molecular Chaperones / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D009474:Neurons / Q000378:metabolism*; D009865:Oocytes; D018091:Receptors, AMPA / Q000235:genetics / Q000378:metabolism*; D013570:Synaptic Membranes / Q000378:metabolism*; D014981:Xenopus
D015220:Calcium Channels; D000076122:Disks Large Homolog 4 Protein; D000091342:Endoplasmic Reticulum Chaperone BiP; D051528:Guanylate Kinases; D006360:Heat-Shock Proteins; D047908:Intracellular Signaling Peptides and Proteins; D008222:Lymphokines; D008565:Membrane Proteins; D018832:Molecular Chaperones; D009419:Nerve Tissue Proteins; D018091:Receptors, AMPA; C113940:Cacng2 protein, mouse; C501447:Dlg4 protein, mouse; C013059:immunoglobulin-binding factors; C033652:postsynaptic density proteins; C104722:glutamate receptor ionotropic, AMPA 2