FIGURE 4.

Structure of rat Ca²⁺/NCS-1 in complex with D2R peptide (PDB code 5AER). A, backbone schematic representation of the NCS-1 in complex with D2R peptide, viewed from the binding interface, with α-helices 1–10 indicated. Two D2R peptides bind independently, one at the N-lobe site (D2B, magenta) and the other at the C-lobe site (D2C, cyan). N and C are the N and C termini of the D2R peptide. Ca²⁺ ions are shown in brown. B, top panel, molecular surface of NCS-1 showing the hydrophobic residues involved in D2R binding in the N-lobe site in yellow and the C-lobe site in brown. Bottom panel, same as top panel but with bound peptides removed and key interacting residues labeled.