Agonist binding to the NMDA receptor drives movement of its cytoplasmic domain without ion flow.
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ABSTRACT:
SUBMITTER: Dore K
PROVIDER: S-EPMC4664357 | biostudies-literature | 2015 Nov
REPOSITORIES: biostudies-literature
Publications
Agonist binding to the NMDA receptor drives movement of its cytoplasmic domain without ion flow.
Dore Kim K Aow Jonathan J Malinow Roberto R
Proceedings of the National Academy of Sciences of the United States of America 20151109 47
The NMDA receptor (R) plays important roles in brain physiology and pathology as an ion channel. Here we examine the ion flow-independent coupling of agonist to the NMDAR cytoplasmic domain (cd). We measure FRET between fluorescently tagged cytoplasmic domains of GluN1 subunits of NMDARs expressed in neurons. Different neuronal compartments display varying levels of FRET, consistent with different NMDARcd conformations. Agonist binding drives a rapid and transient ion flow-independent reduction ...[more]
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