Enables transmembrane transporter binding activity. A structural constituent of presynaptic active zone. Involved in neurotransmitter secretion; positive regulation of gene expression; and regulation of nervous system process. Acts upstream of or within several processes, including adenylate cyclase-modulating G protein-coupled receptor signaling pathway; regulation of exocytosis; and signal release. Located in GABA-ergic synapse and inhibitory synapse. Is active in glutamatergic synapse. Is expressed in testis. Orthologous to human RIMS2 (regulating synaptic membrane exocytosis 2). [provided by Alliance of Genome Resources, Apr 2022]