Involved in pinching off the separated nuclei at the cleavage furrow and in cytokinesis. Required for mitotic integrity and maintenance of chromosomal stability. Protects cells against mitotic errors, centrosomal amplification, micronucleus formation and aneuploidy. Plays a key role of midbody function involving abscission of the daughter cells during cytokinesis and appropriate chromosomal and nuclear segregation into the daughter cells. In mitotic cells, concentrates in the midbody of the cytoplasmic bridge linking daughter cells as they are about to separate during cytokinesis.