Category Ranking

98%

Total Visits

921

Avg Visit Duration

2 minutes

Citations

20

Article Abstract

Glutamate receptors of the AMPA subtype (AMPARs) mediate fast synaptic transmission in the brain. These ionotropic receptors rely on auxiliary subunits known as transmembrane AMPAR regulatory proteins (TARPs) for both trafficking and gating. Recently, a second family of AMPAR binding proteins, referred to as cornichons, were identified and also proposed to function as auxiliary subunits. Cornichons are transmembrane proteins that modulate AMPAR function in expression systems much like TARPs. In the present study we compare the role of cornichons in controlling AMPA receptor function in neurons and HEK cells to that of TARPs. Cornichons mimic some, but not all, of the actions of TARPs in HEK cells; their role in neurons, however, is more limited. Although expressed cornichons can affect the trafficking of AMPARs, they were not detected on the surface of neurons and failed to alter the kinetics of endogenous AMPARs. This neuronal role is more consistent with that of an endoplasmic reticulum (ER) chaperone rather than a bona fide auxiliary subunit.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2941340PMC
http://dx.doi.org/10.1073/pnas.1011706107DOI Listing

Publication Analysis

Top Keywords

tarps cornichons
8
ampa receptor
8
trafficking gating
8
auxiliary subunits
8
hek cells
8
cornichons
6
tarps
5
functional comparison
4
comparison effects
4
effects tarps
4

Similar Publications

AMPA-type ionotropic glutamate receptors (AMPARs) are integral to fast excitatory synaptic transmission and have vital roles in synaptic plasticity, motor coordination, learning and memory. Whereas extensive structural studies have been conducted on recombinant AMPARs and native calcium-impermeable (CI)-AMPARs alongside their auxiliary proteins, the molecular architecture of native calcium-permeable (CP)-AMPARs has remained undefined. Here, to determine the subunit composition, physiological architecture and gating mechanisms of CP-AMPARs, we visualize these receptors, immunoaffinity purified from rat cerebella, and resolve their structures using cryo-electron microscopy (cryo-EM).

View Article and Find Full Text PDF

Transmembrane AMPA receptor regulatory proteins (TARPs) and germ cell-specific gene 1-like protein (GSG1L) are claudin-type AMPA receptor (AMPAR) auxiliary subunits that profoundly regulate glutamatergic synapse strength and plasticity. While AMPAR-TARP complexes have been extensively studied, less is known about GSG1L-containing AMPARs. Here, we show that GSG1L's spatiotemporal expression, native interactome and allosteric sites are distinct.

View Article and Find Full Text PDF

Differential regulation of tetramerization of the AMPA receptor glutamate-gated ion channel by auxiliary subunits.

J Biol Chem

October 2023

Department of Neurobiology & Behavior, Stony Brook University, Stony Brook, New York, USA; Center for Nervous System Disorders, Stony Brook University, Stony Brook, New York, USA; Department of Biochemistry & Cell Biology, Stony Brook University, Stony Brook, New York, USA. Electronic address: lonni

α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) auxiliary subunits are specialized, nontransient binding partners of AMPARs that modulate AMPAR channel gating properties and pharmacology, as well as their biogenesis and trafficking. The most well-characterized families of auxiliary subunits are transmembrane AMPAR regulatory proteins (TARPs), cornichon homologs (CNIHs), and the more recently discovered GSG1-L. These auxiliary subunits can promote or reduce surface expression of AMPARs (composed of GluA1-4 subunits) in neurons, thereby impacting their functional role in membrane signaling.

View Article and Find Full Text PDF

Alternative splicing of AMPA-type glutamate receptors (AMPARs) and allosteric modulation by auxiliary subunits, such as transmembrane AMPAR regulatory proteins (TARPs), are two important mechanisms that regulate the time course of glutamatergic neurotransmission. Prior work has shown that alternative splicing of the flip/flop cassette profoundly regulates TARP γ2 modulation, where flip receptor gating exhibits robust sensitivity to TARPs while flop isoforms are relatively insensitive to TARP modulation. Whether this splice variant-specific regulation extends to other auxiliary subunit families, such as cornichons (CNIHs), GSG1L, or CKAMPs, remains unknown.

View Article and Find Full Text PDF

AMPA receptor (AMPAR) auxiliary subunits are specialized, non-transient binding partners of AMPARs that modulate their ion channel gating properties and pharmacology, as well as their biogenesis and trafficking. The most well characterized families of auxiliary subunits are transmembrane AMPAR regulatory proteins (TARPs) and cornichon homologs (CNIHs) and the more recently discovered GSG1-L. These auxiliary subunits can promote or reduce surface expression of AMPARs in neurons, thereby impacting their functional role in membrane signaling.

View Article and Find Full Text PDF