5ewj
From Proteopedia
CRYSTAL STRUCTURE OF AMINO TERMINAL DOMAINS OF THE NMDA RECEPTOR SUBUNIT GLUN1 AND GLUN2B IN COMPLEX WITH IFENPRODIL
Structural highlights
FunctionNMDZ1_XENLA Component of NMDA receptor complexes that function as heterotetrameric, ligand-gated ion channels with high calcium permeability and voltage-dependent sensitivity to magnesium. Channel activation requires binding of the neurotransmitter glutamate to the epsilon subunit, glycine binding to the zeta subunit, plus membrane depolarization to eliminate channel inhibition by Mg(2+) (PubMed:16214956, PubMed:19524674, PubMed:21677647, PubMed:25008524, PubMed:26912815, PubMed:27135925, Ref.11, PubMed:28232581). Sensitivity to glutamate and channel kinetics depend on the subunit composition (Probable).[1] [2] [3] [4] [5] [6] [7] [PDB:5IOV] Publication Abstract from PubMedNMDA receptors (NMDARs) are glutamate-gated ion channels that play key roles in brain physiology and pathology. Because numerous pathological conditions involve NMDAR overactivation, subunit-selective antagonists hold strong therapeutic potential, although clinical successes remain limited. Among the most promising NMDAR-targeting drugs are allosteric inhibitors of GluN2B-containing receptors. Since the discovery of ifenprodil, a range of GluN2B-selective compounds with strikingly different structural motifs have been identified. This molecular diversity raises the possibility of distinct binding sites, although supporting data are lacking. Using x-ray crystallography, we show that EVT-101, a GluN2B antagonist structurally unrelated to the classical phenylethanolamine pharmacophore, binds at the same GluN1/GluN2B dimer interface as ifenprodil but adopts a remarkably different binding mode involving a distinct subcavity and receptor interactions. Mutagenesis experiments demonstrate that this novel binding site is physiologically relevant. Moreover, in silico docking unveils that GluN2B-selective antagonists broadly divide into two distinct classes according to binding pose. These data widen the allosteric and pharmacological landscape of NMDARs and offer a renewed structural framework for designing next-generation GluN2B antagonists with therapeutic value for brain disorders. A novel binding mode reveals two distinct classes of NMDA receptor GluN2B-selective antagonists.,Stroebel D, Buhl DL, Knafels JD, Chanda PK, Green M, Sciabola S, Mony L, Paoletti P, Pandit J Mol Pharmacol. 2016 Feb 24. pii: mol.115.103036. PMID:26912815[8] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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