1M5C

X-RAY STRUCTURE OF THE GLUR2 LIGAND BINDING CORE (S1S2J) IN COMPLEX WITH Br-HIBO AT 1.65 A RESOLUTION

Summary for 1M5C

• Entry DOI: 10.2210/pdb1m5c/pdb
• Related: 1FTJ 1FTK 1FTL 1FTM 1FTO 1FWO 1GR2 1LB8 1LB9 1M5B 1M5D 1M5E 1M5F
• Descriptor: Glutamate receptor 2, (S)-2-AMINO-3-(4-BROMO-3-HYDROXY-ISOXAZOL-5-YL)PROPIONIC ACID (3 entities in total)
• Functional Keywords: ionotropic glutamate receptor, glur2, ligand binding core, agonist complex, membrane protein
• Biological source: Rattus norvegicus (Norway rat); More
• Cellular location: Cell membrane; Multi-pass membrane protein: P19491
• Total number of polymer chains: 1
• Total formula weight: 29472.72

Authors

Hogner, A.,Kastrup, J.S.,Jin, R.,Liljefors, T.,Mayer, M.L.,Egebjerg, J.,Larsen, I.K.,Gouaux, E. (deposition date: 2002-07-09, release date: 2002-09-18, Last modification date: 2024-10-09)

Primary citation

Hogner, A.,Kastrup, J.S.,Jin, R.,Liljefors, T.,Mayer, M.L.,Egebjerg, J.,Larsen, I.K.,Gouaux, E.
Structural Basis for AMPA Receptor Activation and Ligand Selectivity: Crystal Structures of Five Agonist Complexes with the GluR2 Ligand-binding Core
J.Mol.Biol., 322:93-109, 2002

PubMed Abstract: Glutamate is the principal excitatory neurotransmitter within the mammalian CNS, playing an important role in many different functions in the brain such as learning and memory. In this study, a combination of molecular biology, X-ray structure determinations, as well as electrophysiology and binding experiments, has been used to increase our knowledge concerning the ionotropic glutamate receptor GluR2 at the molecular level. Five high-resolution X-ray structures of the ligand-binding domain of GluR2 (S1S2J) complexed with the three agonists (S)-2-amino-3-[3-hydroxy-5-(2-methyl-2H-tetrazol-5-yl)isoxazol-4-yl]propionic acid (2-Me-Tet-AMPA), (S)-2-amino-3-(3-carboxy-5-methylisoxazol-4-yl)propionic acid (ACPA), and (S)-2-amino-3-(4-bromo-3-hydroxy-isoxazol-5-yl)propionic acid (Br-HIBO), as well as of a mutant thereof (S1S2J-Y702F) in complex with ACPA and Br-HIBO, have been determined. The structures reveal that AMPA agonists with an isoxazole moiety adopt different binding modes in the receptor, dependent on the substituents of the isoxazole. Br-HIBO displays selectivity among different AMPA receptor subunits, and the design and structure determination of the S1S2J-Y702F mutant in complex with Br-HIBO and ACPA have allowed us to explain the molecular mechanism behind this selectivity and to identify key residues for ligand recognition. The agonists induce the same degree of domain closure as AMPA, except for Br-HIBO, which shows a slightly lower degree of domain closure. An excellent correlation between domain closure and efficacy has been obtained from electrophysiology experiments undertaken on non-desensitising GluR2i(Q)-L483Y receptors expressed in oocytes, providing strong evidence that receptor activation occurs as a result of domain closure. The structural results, combined with the functional studies on the full-length receptor, form a powerful platform for the design of new selective agonists.

PubMed: 12215417
DOI: 10.1016/S0022-2836(02)00650-2

Experimental method

X-RAY DIFFRACTION (1.65 Å)