Acts as an effector of RABF2A and RABF2B (By similarity). Involved in vacuolar transport of storage proteins. Regulates membrane trafficking to protein storage vacuoles (PSVs) (Probable). Binds specifically to phosphatidylinositol 3-monophosphate (PtdIns3P) (By similarity). The endosomal localization depends on the active state of RABF2B. No visible phenotype under normal growth conditions.