Fig. 6: Schematic representation of ATD conformational transitions.

a Top-down view of the ATD domain (5IOU [https://doi.org/10.2210/pdb5IOU/pdb]). Red and green filled circles show approximate positions of the SNAP tags labeled by donor and acceptor dyes, respectively. Bullseye denotes the center of rotation. b Model of NMDAR activation by glycine and glutamate. c Model of NMDAR activation for GluN2B- and GluN2A-containing receptors. d Model of NMDAR modulation by pH in the presence of Gly, Glu, and Gly/Glu. Maximal degree of rotation (achieved in Gly/Glu, pH 9.0) corresponds to 45° rotation of ATD dimers after receptor activation39.