Enables several functions, including anion binding activity; calcium-dependent phospholipid binding activity; and metal ion binding activity. Involved in brain development; dendritic spine organization; and regulation of NMDA receptor activity. Located in several cellular components, including dendritic spine; postsynaptic membrane; and secretory vesicle. Is extrinsic component of membrane. Part of protein-containing complex. Is active in cholinergic synapse and neuromuscular junction. Is extrinsic component of synaptic vesicle membrane. Colocalizes with Golgi apparatus. Orthologous to human RPH3A (rabphilin 3A). [provided by Alliance of Genome Resources, Apr 2022]