4kcd

From Proteopedia

Crystal Structure of the NMDA Receptor GluN3A Ligand Binding Domain Apo State

Structural highlights

4kcd 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.
Method:	X-ray diffraction, Resolution 1.68Å
Ligands:
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

NMD3A_RAT NMDA receptor subtype of glutamate-gated ion channels with reduced single-channel conductance, low calcium permeability and low voltage-dependent sensitivity to magnesium. Mediated by glycine. May play a role in the development of dendritic spines. May also play a role in PPP2CB-NMDAR mediated signaling mechanism.

Publication Abstract from PubMed

The NMDA receptor family of glutamate receptor ion channels is formed by obligate heteromeric assemblies of GluN1, GluN2, and GluN3 subunits. GluN1 and GluN3 bind glycine, whereas GluN2 binds glutamate. Crystal structures of the GluN1 and GluN3A ligand-binding domains (LBDs) in their apo states unexpectedly reveal open- and closed-cleft conformations, respectively, with water molecules filling the binding pockets. Computed conformational free energy landscapes for GluN1, GluN2A, and GluN3A LBDs reveal that the apo-state LBDs sample closed-cleft conformations, suggesting that their agonists bind via a conformational selection mechanism. By contrast, free energy landscapes for the AMPA receptor GluA2 LBD suggest binding of glutamate via an induced-fit mechanism. Principal component analysis reveals a rich spectrum of hinge bending, rocking, twisting, and sweeping motions that are different for the GluN1, GluN2A, GluN3A, and GluA2 LBDs. This variation highlights the structural complexity of signaling by glutamate receptor ion channels.

Conformational Analysis of NMDA Receptor GluN1, GluN2, and GluN3 Ligand-Binding Domains Reveals Subtype-Specific Characteristics.,Yao Y, Belcher J, Berger AJ, Mayer ML, Lau AY Structure. 2013 Oct 8;21(10):1788-99. doi: 10.1016/j.str.2013.07.011. Epub 2013, Aug 22. PMID:23972471^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Yao Y, Belcher J, Berger AJ, Mayer ML, Lau AY. Conformational Analysis of NMDA Receptor GluN1, GluN2, and GluN3 Ligand-Binding Domains Reveals Subtype-Specific Characteristics. Structure. 2013 Oct 8;21(10):1788-99. doi: 10.1016/j.str.2013.07.011. Epub 2013, Aug 22. PMID:23972471 doi:http://dx.doi.org/10.1016/j.str.2013.07.011