Predicted to enable transmembrane transporter binding activity. Involved in calcium-ion regulated exocytosis and regulation of synapse organization. Acts upstream of or within regulation of synaptic vesicle exocytosis. Is active in glutamatergic synapse and postsynaptic cytosol. Orthologous to human RIMS3 (regulating synaptic membrane exocytosis 3). [provided by Alliance of Genome Resources, Apr 2022]