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

Article Details

Citation

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
DrugTargetKindOrganismPharmacological ActionActions
Glutamic acidGlutamate receptor ionotropic, kainate 4ProteinHumans
Unknown
Not AvailableDetails
Polypeptides
NameUniProt ID
Glutamate receptor ionotropic, kainate 1P39086Details