N-methyl-D-aspartate receptor C-terminal domain–PDZ scaffold protein interface (NMDAR-PDZ interface)

The N-methyl-D-aspartate receptor (NMDAR) C-terminal domain–PDZ scaffold protein interface is a specialized protein-protein interaction (PPI) site that anchors NMDARs to the postsynaptic density and couples them to intracellular signaling pathways [1.1.2, 1.4.1]. The interface primarily involves the interaction between the C-terminal PDZ-binding motifs of NMDAR subunits, such as GluN2B, and the PDZ domains of scaffolding proteins like Postsynaptic Density Protein 95 (PSD-95) [1.1.3, 1.4.3]. This coupling is essential for physiological processes like synaptic plasticity, learning, and memory, but it also facilitates the recruitment of neuronal nitric oxide synthase (nNOS) [1.1.1, 1.5.2]. Under conditions of excitotoxicity, such as during an ischemic stroke, excessive NMDAR activation leads to overproduction of nitric oxide through this complex, causing neuronal death [1.2.2, 1.3.1]. Therapeutic agents like Nerinetide (NA-1) are designed to competitively inhibit this interface, thereby uncoupling NMDARs from toxic downstream signaling without blocking the receptor's essential ionotropic functions [1.2.3, 1.4.4]. This approach offers a neuroprotective strategy that avoids the severe side effects typically associated with direct NMDAR antagonists [1.3.4, 1.5.1]. Clinical development of inhibitors targeting this interface has primarily focused on acute ischemic stroke, where preserving neuronal viability during the reperfusion phase is critical [1.2.5].

Other names

NMDAR-PSD-95 interactionGluN2B-PSD-95 interfaceNMDAR-MAGUK interfaceNMDAR-PDZ interactionGluN2B-PSD-95 complex

Competitive inhibition of the protein-protein interaction between the NMDAR C-terminal PDZ-binding motif and the PDZ domains of scaffold proteins (primarily PSD-95). This uncouples the receptor from downstream neurotoxic signaling pathways, such as the activation of neuronal nitric oxide synthase (nNOS), without inhibiting the physiological ionotropic function of the NMDAR.