Acts upstream of or within positive regulation of synapse assembly. Predicted to be located in membrane. Predicted to be integral component of membrane. Predicted to be active in extracellular matrix and extracellular space. Is expressed in several structures, including central nervous system; dorsal root ganglion; embryo mesenchyme; lip; and sensory organ. Orthologous to human LRRN1 (leucine rich repeat neuronal 1). [provided by Alliance of Genome Resources, Apr 2022]