3QLT

Crystal structure of a GluK2 (GluR6) glycan wedge homodimer assembly

Summary for 3QLT

• Entry DOI: 10.2210/pdb3qlt/pdb
• Related: 3H6G 3OLZ 3OM0 3QLU 3QLV
• Descriptor: Glutamate receptor, ionotropic kainate 2, 2-acetamido-2-deoxy-beta-D-glucopyranose (2 entities in total)
• Functional Keywords: membrane protein, glycosylation
• Biological source: Rattus norvegicus (rat)
• Total number of polymer chains: 2
• Total formula weight: 90973.59

Authors

Kumar, J.,Mayer, M.L. (deposition date: 2011-02-03, release date: 2011-08-03, Last modification date: 2024-11-06)

Primary citation

Kumar, J.,Schuck, P.,Mayer, M.L.
Structure and assembly mechanism for heteromeric kainate receptors.
Neuron, 71:319-331, 2011

PubMed Abstract: Native glutamate receptor ion channels are tetrameric assemblies containing two or more different subunits. NMDA receptors are obligate heteromers formed by coassembly of two or three divergent gene families. While some AMPA and kainate receptors can form functional homomeric ion channels, the KA1 and KA2 subunits are obligate heteromers which function only in combination with GluR5-7. The mechanisms controlling glutamate receptor assembly involve an initial step in which the amino terminal domains (ATD) assemble as dimers. Here, we establish by sedimentation velocity that the ATDs of GluR6 and KA2 coassemble as a heterodimer of K(d) 11 nM, 32,000-fold lower than the K(d) for homodimer formation by KA2; we solve crystal structures for the GluR6/KA2 ATD heterodimer and heterotetramer assemblies. Using these structures as a guide, we perform a mutant cycle analysis to probe the energetics of assembly and show that high-affinity ATD interactions are required for biosynthesis of functional heteromeric receptors.

PubMed: 21791290
DOI: 10.1016/j.neuron.2011.05.038

Experimental method

X-RAY DIFFRACTION (2.988 Å)