title: Cloning of a brain N-methyl-D-aspartate- and D, L-epsilon-2-amino-4-propyl-5-phosphono-3-pentanoic acid (CGP 39653)-binding protein.
abstract: A complex of four proteins isolated from neuronal membranes has ligand binding sites for N-methyl-d-aspartate (NMDA) receptor agonists and antagonists and forms NMDA-activated ion channels upon reconstitution into lipid membranes. In this study, the cDNA of a subunit of this complex containing binding sites for the competitive antagonists of NMDA receptors was cloned. The cDNA clone coded for a protein of 719 amino acids (78.9 kDa). The expressed protein had binding activity for the agonists l-[3H]glutamate and [3H]glycine, the antagonist (+/-)-[3H]-(E)-2-amino-4-propyl-5-phosphonopentanoic acid ([3H]CGP 39653), but not the ion channel inhibitors. The cloned cDNA had no homology to other cloned cDNAs. Northern blot analyses indicated high expression of an 3.8 kb poly(A+) RNA in brain, but not in other tissues. These findings indicate that proteins that have recognition sites for NMDA receptor activators and inhibitors and that differ from the well-characterized NMDA receptor proteins NR1-3 are expressed in mammalian brain.
authors.affiliation: Department of Pharmacology and Toxicology, Center for Neurobiology and Immunology Research, University of Kansas, Lawrence 66045, USA.
authors.forename: K N
authors.initials: KN
authors.lastname: Kumar
authors.forename: P S
authors.initials: PS
authors.lastname: Johnson
authors.forename: X
authors.initials: X
authors.lastname: Chen
authors.forename: R
authors.initials: R
authors.lastname: Pal
authors.forename: M
authors.initials: M
authors.lastname: Ahmad
authors.forename: T
authors.initials: T
authors.lastname: Ragland
authors.forename: C
authors.initials: C
authors.lastname: Bigge
authors.forename: E K
authors.initials: EK
authors.lastname: Michaelis
mesh_terms: D015763:2-Amino-5-phosphonovalerate / Q000031:analogs & derivatives* / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002352:Carrier Proteins / Q000235:genetics* / Q000302:isolation & purification; D003001:Cloning, Molecular; D018690:Excitatory Amino Acid Agonists / Q000378:metabolism*; D018691:Excitatory Amino Acid Antagonists / Q000378:metabolism*; D006624:Hippocampus / Q000378:metabolism; D008297:Male; D008969:Molecular Sequence Data; D016202:N-Methylaspartate / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D010879:Piperazines / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D016194:Receptors, N-Methyl-D-Aspartate / Q000819:agonists / Q000037:antagonists & inhibitors / Q000235:genetics*
chemical_list: D002352:Carrier Proteins; D018690:Excitatory Amino Acid Agonists; D018691:Excitatory Amino Acid Antagonists; D009419:Nerve Tissue Proteins; D010879:Piperazines; D016194:Receptors, N-Methyl-D-Aspartate; C069052:CGP 39653; C104291:3-(2-carboxypiperazine-4-yl)propyl-1-phosphate; D016202:N-Methylaspartate; D015763:2-Amino-5-phosphonovalerate