A functional AMPA receptor-calcium channel complex in the postsynaptic membrane.
Ca(2+) channels play critical roles in the regulation of synaptic activity. In contrast to the well established function of voltage-activated Ca(2+) channels in the presynaptic membrane for neurotransmitter release, some studies are just beginning to elucidate the functions of the Ca(2+) channels in the postsynaptic membrane. In this study, we demonstrated the functional association of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) receptors with the neuronal Ca(2+) channels. A series of biochemical studies showed the specific association of Ca(v)2.1 (alpha(1A)-class) and Ca(v)2.2 (alpha(1B)-class) with AMPA receptors in the postsynaptic membrane. Our electrophysiological and Ca(2+) imaging analyses of recombinant Ca(v)2.1 and AMPA receptors also showed functional coupling of the two channels. Considering the critical roles of postsynaptic intracellular concentration of Ca(2+) ([Ca(2+)](i)) increase and AMPA receptor trafficking for long-term potentiation (LTP) and long-term depression (LTD), the functional association of Ca(2+) channels with the AMPA receptors may provide new insights into the mechanism of synaptic plasticity.
Howard Hughes Medical Institute and Departments of Physiology and Biophysics, Internal Medicine, and Neurology, University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, IA 52242, USA.
Myoung-Goo
MG
Kang
Chien-Chang
CC
Chen
Minoru
M
Wakamori
Yuji
Y
Hara
Yasuo
Y
Mori
Kevin P
KP
Campbell
D000818:Animals; D015153:Blotting, Western; D015220:Calcium Channels / Q000378:metabolism / Q000502:physiology*; D002460:Cell Line; D006801:Humans; D047468:Immunoprecipitation; D011485:Protein Binding; D011817:Rabbits; D018091:Receptors, AMPA / Q000378:metabolism / Q000502:physiology*; D013347:Subcellular Fractions / Q000378:metabolism; D013570:Synaptic Membranes / Q000502:physiology*
D015220:Calcium Channels; D018091:Receptors, AMPA