Enables several functions, including glycine binding activity; neurotransmitter binding activity; and neurotransmitter receptor activity. Involved in ionotropic glutamate receptor signaling pathway. Part of NMDA selective glutamate receptor complex. Is active in hippocampal mossy fiber to CA3 synapse. Is integral component of postsynaptic density membrane. Orthologous to human GRIN3B (glutamate ionotropic receptor NMDA type subunit 3B). [provided by Alliance of Genome Resources, Apr 2022]