Plays a role in the reorganization of the cytoskeleton, endocytosis and cellular vesicle trafficking, both during interphase and at the end of mitotic cell divisions. Required for efficient progress through mitosis and cytokinesis. Required for normal formation of the cleavage furrow at the end of mitosis. Modulates endocytosis of cell-surface proteins. Promotes membrane tubulation (in vitro). May promote the formation of macropinosomes (By similarity). Primarily detected in the cytosol. A minor proportion is membrane-bound (By similarity). The PX and BAR domains mediate association with membranes and are required for membrane tubulation. Belongs to the sorting nexin family.