GTP-hydrolysis activating protein (GAP) for small GTPase RAB22A, converting active RAB22A-GTP to the inactive form RAB22A-GDP (By similarity). Plays a role in endocytosis and intracellular protein transport. Recruited by ANK2 to phosphatidylinositol 3-phosphate (PI3P)-positive early endosomes, where it inactivates RAB22A, and promotes polarized trafficking to the leading edge of the migrating cells. Part of the ANK2/RABGAP1L complex which is required for the polarized recycling of fibronectin receptor ITGA5 ITGB1 to the plasma membrane that enables continuous directional cell migration (By similarity). Interacts with ANK2. Colocalizes on endosomes partially with EEA1 (By similarity). Colocalizes and cotransports on motile vesicles with ANK2 (By similarity). The arginine and glutamine fingers are critical for the GTPase-activating mechanism, they pull out Rab's 'switch 2' glutamine and insert in Rab's active site.