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kainate selective glutamate receptor complex

Definition

Target type: cellularcomponent

An assembly of four or five subunits which form a structure with an extracellular N-terminus and a large loop that together form the ligand binding domain. The C-terminus is intracellular. The ionotropic glutamate receptor complex itself acts as a ligand gated ion channel; on binding glutamate, charged ions pass through a channel in the center of the receptor complex. Kainate receptors are multimeric assemblies of GluK1-3 (also called GluR5-7), GluK4 (KA1) and GluK5 (KA2) subunits. [GOC:bf, http://www.bris.ac.uk/Depts/Synaptic/info/glutamate.html, PMID:18655795]

The kainate-selective glutamate receptor complex is a transmembrane protein complex that plays a crucial role in excitatory neurotransmission in the central nervous system. It is composed of multiple subunits, primarily GluK1-GluK5, which assemble into tetrameric structures to form functional ion channels. The cellular component of the kainate receptor complex can be broadly divided into three main domains: the extracellular domain, the transmembrane domain, and the intracellular domain.

**Extracellular Domain:**

- **Ligand-binding domain:** This domain is located at the N-terminus of each subunit and is responsible for binding glutamate, the primary neurotransmitter that activates the receptor. The glutamate binding site is highly specific for kainate, a synthetic analog of glutamate.
- **Dimerization domain:** This domain mediates the interaction between two subunits to form dimers, which are essential for the formation of the tetrameric complex.
- **Glycosylation sites:** The extracellular domain contains glycosylation sites, where sugars are attached to the protein. Glycosylation can influence the trafficking, stability, and activity of the receptor.

**Transmembrane Domain:**

- **Ion channel pore:** This domain forms the central pore of the receptor, which allows the passage of ions across the cell membrane. The pore is selective for cations, primarily sodium and potassium ions.
- **Voltage-sensing domain:** In some kainate receptor subunits, this domain is responsible for detecting changes in membrane potential, which can modulate the activity of the receptor.

**Intracellular Domain:**

- **C-terminus:** This domain is located at the C-terminus of each subunit and contains a variety of binding sites for intracellular signaling proteins. These interactions can influence the phosphorylation, trafficking, and activity of the receptor.
- **PDZ-binding domain:** This domain interacts with PDZ domain-containing proteins, which are involved in protein scaffolding and signaling.
- **Scaffolding proteins:** The intracellular domain can also bind to other scaffolding proteins, which can help to organize and regulate the receptor complex.

The cellular component of the kainate receptor complex is highly dynamic and undergoes a complex series of interactions with other proteins and signaling pathways. This complex interplay contributes to the fine-tuning of neuronal excitability and synaptic plasticity.'
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Proteins (5)

ProteinDefinitionTaxonomy
Glutamate receptor ionotropic, kainate 5A glutamate receptor ionotropic, kainate 5 that is encoded in the genome of human. [PRO:DNx, UniProtKB:Q16478]Homo sapiens (human)
Glutamate receptor ionotropic, kainate 2A glutamate receptor ionotropic, kainate 2 that is encoded in the genome of human. [PRO:DNx, UniProtKB:Q13002]Homo sapiens (human)
Glutamate receptor ionotropic, kainate 4A glutamate receptor ionotropic, kainate 4 that is encoded in the genome of human. [PRO:DNx, UniProtKB:Q16099]Homo sapiens (human)
Glutamate receptor ionotropic, kainate 1A glutamate receptor ionotropic, kainate 1 that is encoded in the genome of human. [PRO:DNx, UniProtKB:P39086]Homo sapiens (human)
Glutamate receptor ionotropic, kainate 3A glutamate receptor ionotropic, kainate 3 that is encoded in the genome of human. [PRO:DNx, UniProtKB:Q13003]Homo sapiens (human)

Compounds (20)

CompoundDefinitionClassesRoles
alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acidalpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid: An IBOTENIC ACID homolog and glutamate agonist. The compound is the defining agonist for the AMPA subtype of glutamate receptors (RECEPTORS, AMPA). It has been used as a radionuclide imaging agent but is more commonly used as an experimental tool in cell biological studies.non-proteinogenic alpha-amino acid
kainic acidKainic Acid: (2S-(2 alpha,3 beta,4 beta))-2-Carboxy-4-(1-methylethenyl)-3-pyrrolidineacetic acid. Ascaricide obtained from the red alga Digenea simplex. It is a potent excitatory amino acid agonist at some types of excitatory amino acid receptors and has been used to discriminate among receptor types. Like many excitatory amino acid agonists it can cause neurotoxicity and has been used experimentally for that purpose.dicarboxylic acid;
L-proline derivative;
non-proteinogenic L-alpha-amino acid;
pyrrolidinecarboxylic acid
antinematodal drug;
excitatory amino acid agonist
glutamic acidglutamic acid : An alpha-amino acid that is glutaric acid bearing a single amino substituent at position 2.

Glutamic Acid: A non-essential amino acid naturally occurring in the L-form. Glutamic acid is the most common excitatory neurotransmitter in the CENTRAL NERVOUS SYSTEM.
glutamic acid;
glutamine family amino acid;
L-alpha-amino acid;
proteinogenic amino acid
Escherichia coli metabolite;
ferroptosis inducer;
micronutrient;
mouse metabolite;
neurotransmitter;
nutraceutical
sym 2081
5-fluorowillardiine3-(5-fluorouracil-1-yl)-L-alanine : An alanine derivative that is L-alanine bearing a 5-fluorouracil-1-yl substituent at position 3. A more potent and selective AMPA receptor agonist (at hGluR1 and hGluR2) than AMPA itself (Ki = 14.7, 25.1, and 1820 nM for hGluR1, hGluR2 and hGluR5 respectively).

5-fluorowillardiine: a glutamate agonist; RN given for (S)-isomer
L-alanine derivative;
non-proteinogenic L-alpha-amino acid;
organofluorine compound
AMPA receptor agonist
ly 293558tezampanel: structure given in first source; an AMPA receptor antagonist
ns 1608NS 1608: a BK(Ca) channel openerureas
alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid
5-bromowillardiine5-bromowillardiine: acts as a kainate-like agonist on chick EAA receptors expressed in Xenopus oocytes; RN given refers to (S)-isomer; RN for cpd without isomeric designation not avail 5/91
willardiine3-(uracil-1-yl)-L-alanine : The 3-(uracil-1-yl) derivative of L-alanine.

willardiine: isolated from seeds of Acacia willariana; structure
amino acid zwitterion;
L-alanine derivative;
non-proteinogenic L-alpha-amino acid
(S)-ATPA(S)-ATPA : A non-proteinogenic L-alpha-amino acid that is L-alanine in which one of the methyl hydrogens is replaced by a 5-tert-butyl-3-hydroxy-isooxazol-4-yl group.isoxazoles;
non-proteinogenic L-alpha-amino acid
metabolite
ly382884benzoic acids
4-bromohomoibotenic acid, (rs)-isomer
2,3-dioxo-6-nitro-7-sulfamoylbenzo(f)quinoxaline2,3-dioxo-6-nitro-7-sulfamoylbenzo(f)quinoxaline: structure given in first source; neuroprotectant for cerebral ischemia; AMPA receptor antagonistnaphthalenes;
sulfonic acid derivative
ubp 310UBP 310: a GluR5 antagonist; structure in first source
ubp 302
dysiherbainedysiherbaine : A furopyran that is (3aR,7aR)-hexahydro-2H-furo[3,2-b]pyran substituted by carboxy, (2S)-2-amino-2-carboxyethyl, hydroxy and methylamino groups at positions 2, 2, 6, and 7, respectively (the 2R,3aR,6S,7R,7aR-stereoisomer). A convulsant isolated from the marine sponge Dysidea herbacea that has high affinity for kainate ionotropic glutamate receptors.

dysiherbaine: an exitotoxic amino acid; structure in first source
amino dicarboxylic acid;
furopyran;
hydroxy carboxylic acid;
secondary amino compound
animal metabolite;
excitatory amino acid agonist;
marine metabolite;
neurotoxin
ns 1652NS 1652: an anion conductance inhibitor; structure in first source
ns3694NS3694: an apoptosome inhibitorureas
ubp296UBP296: potent and selective kainate receptor antagonist; structure in first sourcealpha-amino acid