Crystal structure of the iGluR2 ligand binding core (S1S2J-N775S) in complex with a dimeric positive modulator as well as glutamate at 2.25 A resolution
3bbr is a 2 chain structure with sequence from Rattus norvegicus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
GRIA2_RAT Receptor for glutamate that functions as ligand-gated ion channel in the central nervous system and plays an important role in excitatory synaptic transmission. L-glutamate acts as an excitatory neurotransmitter at many synapses in the central nervous system. Binding of the excitatory neurotransmitter L-glutamate induces a conformation change, leading to the opening of the cation channel, and thereby converts the chemical signal to an electrical impulse. The receptor then desensitizes rapidly and enters a transient inactive state, characterized by the presence of bound agonist. In the presence of CACNG4 or CACNG7 or CACNG8, shows resensitization which is characterized by a delayed accumulation of current flux upon continued application of glutamate.[1][2][3][4][5][6][7][8][9][10][11][12][13][14]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Dimeric positive allosteric modulators of ionotropic glutamate receptors were designed, synthesized, and characterized pharmacologically in electrophysiological experiments. The designed compounds are dimers of arylpropylsulfonamides and have been constructed without a linker. The monomeric arylpropylsulfonamides were derived from known modulators and target the cyclothiazide-binding site at the AMPA receptors. The three stereoisomers--R,R, meso, and S,S--of the two constructed dimers were prepared, and in vitro testing showed the R,R forms to be the most potent stereoisomers. The biarylpropylsulfonamides have dramatically increased potencies, more than three orders of magnitude higher than the corresponding monomers. Dimer (R,R)-2a was cocrystallized with the GluR2-S1S2J construct, and an X-ray crystallographic analysis showed (R,R)-2a to bridge two identical binding pockets on two neighboring GluR2 subunits. Thus, this is biostructural evidence of a homomeric dimer bridging two identical receptor-binding sites.
Structural proof of a dimeric positive modulator bridging two identical AMPA receptor-binding sites.,Kaae BH, Harpsoe K, Kastrup JS, Sanz AC, Pickering DS, Metzler B, Clausen RP, Gajhede M, Sauerberg P, Liljefors T, Madsen U Chem Biol. 2007 Nov;14(11):1294-303. PMID:18022568[15]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
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↑Frandsen A, Pickering DS, Vestergaard B, Kasper C, Nielsen BB, Greenwood JR, Campiani G, Fattorusso C, Gajhede M, Schousboe A, Kastrup JS. Tyr702 is an important determinant of agonist binding and domain closure of the ligand-binding core of GluR2. Mol Pharmacol. 2005 Mar;67(3):703-13. Epub 2004 Dec 9. PMID:15591246 doi:10.1124/mol.104.002931
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↑Kasper C, Pickering DS, Mirza O, Olsen L, Kristensen AS, Greenwood JR, Liljefors T, Schousboe A, Watjen F, Gajhede M, Sigurskjold BW, Kastrup JS. The structure of a mixed GluR2 ligand-binding core dimer in complex with (S)-glutamate and the antagonist (S)-NS1209. J Mol Biol. 2006 Apr 7;357(4):1184-201. Epub 2006 Jan 31. PMID:16483599 doi:10.1016/j.jmb.2006.01.024
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↑Kaae BH, Harpsoe K, Kastrup JS, Sanz AC, Pickering DS, Metzler B, Clausen RP, Gajhede M, Sauerberg P, Liljefors T, Madsen U. Structural proof of a dimeric positive modulator bridging two identical AMPA receptor-binding sites. Chem Biol. 2007 Nov;14(11):1294-303. PMID:18022568 doi:10.1016/j.chembiol.2007.10.012
