Spotlight

The centrosome is the microtubule organizing center important for the establishment of the mitotic spindle in animal cells. In mitosis, cells normally contain two centrosomes, one for each pole of the bipolar spindle. If a cell acquires additional centrosomes, it has the potential to build a multi-polar spindle which could lead to catastrophic errors in chromosome segregation. Although such an event is unlikely to produce viable daughter cells, an increase in centrosome number has been shown to cause chromosome instability and produce anneuploid daughter cells.1-3 Accordingly, supernumerary centrosomes have been found in a variety of human cancers and accumulation of additional centrosomes has been associated with the process of tumorigenesis.1,4-9 Despite the obvious importance of regulating centrosome number, relatively little is known about how centrosome duplication is regulated. Perhaps surprisingly, several recent studies, including three arti