Enables ionotropic glutamate receptor binding activity. Involved in memory; regulation of long-term neuronal synaptic plasticity; and visual learning. Acts upstream of or within positive regulation of excitatory postsynaptic potential and receptor localization to synapse. Located in excitatory synapse and postsynaptic density membrane. Is integral component of postsynaptic density membrane. Is active in glutamatergic synapse. Is expressed in central nervous system; metencephalon lateral wall; and retina inner nuclear layer. Orthologous to human NETO1 (neuropilin and tolloid like 1). [provided by Alliance of Genome Resources, Apr 2022]