Making the Final Cut

Abstract

Mitosis produces two daughter nuclei, but cell division is not complete until the cytoplasm is successfully divided into two distinct daughter cells during a process known as cytokinesis. Compared with mitosis, relatively little is known about the molecular processes involved in cytokinesis. Kanazawa et al. found that a lipid metabolite, psychosine, can inhibit cytokinesis and lead to the production of multinucleate cells. In cells treated with psychosine (bottom panels), cellular actin (stained green) “clots” rather than forming a contractile ring around the plane of division, as do untreated cells (top panels). After mitosis, both nuclei (the red-stained DNA) remain in the same psychosine-treated cell. These observations correlate with the production of multinuclear cells in the brains of patients who have the neurological disorder globoid cell leukodystrophy and who also accumulate psychosine through defects in lipid metabolism.—SMH