Enables phosphatidylinositol-4,5-bisphosphate 5-phosphatase activity. Predicted to be involved in several processes, including dephosphorylation; intracellular distribution of mitochondria; and synaptic vesicle endocytosis. Predicted to be located in axon terminus; cytoplasmic microtubule; and ruffle membrane. Predicted to be extrinsic component of mitochondrial outer membrane. Predicted to be active in perinuclear region of cytoplasm and presynapse. Is expressed in several structures, including alimentary system; genitourinary system; liver; nose; and spleen. Orthologous to human SYNJ2 (synaptojanin 2). [provided by Alliance of Genome Resources, Apr 2022]