Required for normal morphology of late endosomes and/or lysosomes in neurons. Binds phosphatidylinositol 3,5-bisphosphate (PtdIns(3,5)P2) (By similarity). The CRAL-TRIO domain is required for targeting to the membrane and for binding PtdIns(3,5)P2. Binding to PtdIns(3,5)P2 is not required for localization.