Acts upstream of or within positive regulation of amyloid-beta formation and positive regulation of synapse assembly. Located in glutamatergic synapse. Is integral component of postsynaptic density membrane. Is expressed in several structures, including alimentary system; central nervous system; embryo mesenchyme; future brain; and male reproductive gland or organ. Orthologous to human LRRTM3 (leucine rich repeat transmembrane neuronal 3). [provided by Alliance of Genome Resources, Apr 2022]