Enables calcium channel regulator activity and voltage-gated calcium channel activity. Involved in chemical synaptic transmission and regulation of synaptic vesicle exocytosis. Acts upstream of or within several processes, including behavioral fear response; learning or memory; and transmission of nerve impulse. Located in glutamatergic synapse and presynaptic membrane. Is expressed in several structures, including alimentary system; brain; eye; reproductive system; and spinal cord. Orthologous to human GRM7 (glutamate metabotropic receptor 7). [provided by Alliance of Genome Resources, Apr 2022]