Enables sodium channel regulator activity and transmembrane transporter binding activity. Involved in negative regulation of cation channel activity; regulation of membrane depolarization; and regulation of sodium ion transmembrane transporter activity. Predicted to be located in synapse. Predicted to be active in cytoplasm and nucleus. Human ortholog(s) of this gene implicated in developmental and epileptic encephalopathy 47. Orthologous to human FGF12 (fibroblast growth factor 12). [provided by Alliance of Genome Resources, Apr 2022]