The cartoon structure of iGluA2-LBD (ligand-binding domain) dimer. (A) Showing the dimer interface region (in arbitrary orientation), and the five subsites A, B, C, B’ and C’ in the ligand binding-site region as defined by Ptak et al. . (B) Orthogonal view with respect to Figure 1A to show inverted U-shaped crevice. Two monomers are colored in cyan and green. All cartoon figures were produced with the PyMOL program (http://www.pymol.org), unless otherwise mentioned.