Figure 2.

Schematic diagram of an individual subunit of iGlu receptor. (A) Proposed membrane topology of an individual iGluR subunit (NR1/NR2). (B) The ligand-binding region in the iGluR is formed by two separate extra cellular loops containing the S1 and S2 domains. There are three hydrophobic trans membrane domains, TM1, TM2, and TM3 which fully span the membrane. A re-entrant membrane loop forms the pore that lines an ion channel in iGlu receptors. The amino terminal domain (N) and the ligand binding domain are located in extracellular space. The carboxy-terminal (C) domains situate intracellular and regulatory activity. The model was adapted and modified from Dingledine et al. (1999), Koo and Hampson (2010).