The centrosome is a major organizer of the cy-toskeleton in animal cells. The precise duplication of this organelle at each cell cycle ensures proper organization of the mitotic apparatus and chromosome segregation. However, cen-trosomes are dispensable for cell division during some stages of development in mouse and Drosophila. Bornens (p. 422) reviews the role of the centrosome in a variety of organisms and discusses how and why they can be dispensed with on occasion. In this vein, Azimzadeh et al. (p. 461, published online 5 January) now demonstrate that centro-somes in Planarian flatworms, best known for their remarkable regeneration abilities, are completely dispensable for both cell division and development.
展开▼
