Architecture and function of NMDA receptors: an evolutionary perspective

Area of Science:

• Neuroscience
• Evolutionary Biology
• Molecular Biology

Background:

• Ionotropic glutamate receptors (iGluRs) are vital ligand-gated ion channels in excitatory neurotransmission.
• NMDA receptors (NMDARs), a key iGluR subclass, are central to central nervous system (CNS) synaptic plasticity.
• Understanding NMDAR evolution is crucial for comprehending nervous system development.

Purpose of the Study:

• To analyze the evolutionary history of NMDARs using genomic and structural data.
• To compare NMDARs with other iGluRs, highlighting unique properties.
• To explore how NMDAR molecular evolution facilitated nervous system development.

Main Methods:

• Phylogenetic analysis of iGluR genes.
• Examination of atomic structures of NMDARs and related receptors.
• Integration of physiological and mechanistic data.

Main Results:

• Evolutionary analysis reveals how NMDAR motifs and sequences shaped their architecture and function.
• Distinctive NMDAR properties in ligand binding, gating, permeation, and signaling were identified.
• Commonalities and differences between NMDARs and other iGluRs were elucidated.

Conclusions:

• Specific molecular properties of iGluRs evolved to provide novel functions for the developing nervous system.
• NMDAR evolution is intrinsically linked to the complexity of nervous system structures from early metazoans to mammals.
• This review provides a molecular framework for understanding NMDAR evolution and its impact on brain function.