cDNA cloning and functional properties of human glutamate receptor EAA3 (GluR5) in homomeric and heteromeric configuration.

Article Details

Citation

Copy to clipboard

Korczak B, Nutt SL, Fletcher EJ, Hoo KH, Elliott CE, Rampersad V, McWhinnie EA, Kamboj RK

cDNA cloning and functional properties of human glutamate receptor EAA3 (GluR5) in homomeric and heteromeric configuration.

Receptors Channels. 1995;3(1):41-9.

PubMed ID

8589992 [ View in PubMed

]

Abstract

We have isolated a new member of the human glutamate receptor family from a fetal brain cDNA library. This cDNA clone, designated EAA3a, shares a 90% nucleotide identity with the previously reported rat GluR5-2b cDNA splice variant and differed from human GluR5-1d in the amino and carboxy terminal regions. Cell lines stably expressing EAA3a protein formed homomeric ligand-gated ion channels responsive, in order of decreasing affinity to domoate, kainate, L-glutamate and (RS)-alpha-amino-3-hydroxy-5- methylisoxazole-propionate (AMPA). Kainate-evoked currents showed partial desensitization that was reduced on incubation with concanavalin A (conA) but not cyclothiazide and were attenuated by the non-N-methyl-D-aspartate (NMDA) receptor antagonist CNQX (6-cyano-7-nitro-quinoxalinedione). Coexpression of EAA3a and human EAA1 cDNAs in HEK 293 cells formed a heteromeric channel with unique properties. Kainate and AMPA activated the heteromeric channel with significantly higher affinities than observed for EAA3a alone. Ligand binding studies with the recombinant EAA3a receptor expressed in mammalian cells indicated a high affinity kainate binding site (Kd = 120 +/- 15.0 nM). The relative potency of compounds in displacing [3H]-kainate binding to EAA3a receptor was: domoate > kainate > L-glutamate = quisqualate > 6,7-dinitroquinoxaline-2,3-dione (DNQX) = CNQX > AMPA > dihydrokainate > NMDA.

DrugBank Data that Cites this Article

Drug Targets

Drug	Target	Kind	Organism	Pharmacological Action	Actions
Glutamic acid	Glutamate receptor ionotropic, kainate 4	Protein	Humans	Unknown	Not Available	Details

Polypeptides

Name	UniProt ID
Glutamate receptor ionotropic, kainate 1	P39086	Details