Nature Cell Biology 1, pp 88 - 93

Chromosomes carry the essential genetic information of each cell. When cells divide they need to make sure their chromosomes get evenly distributed onto their new-born daughter cells. Too many or too little chromosomes can have deleterious effects and switch a cell into a cancer cell. The machinery that helps cells divide must therefore itself be set up correctly at the appropriate time to ensure proper cell division. Key components of this process are the two centrosomes that first build up and then hold together the mechanic machinery that pulls cells and their chromosomes apart. Before a cell decides to divide, it needs first needs to duplicate its centrosomes and coordinate this with the replication of its genetic material.

A paper in the June issue of Nature Cell Biology by Erich Nigg from the University of Geneva now sheds further light on the events that control centrosomes duplication. A cellular factor known as E2F and complex of an enzyme called cdk2 and a protein called cyclin A are required to trigger the replication of chromosomes. Erich Nigg and colleagues have now found that E2F, cdk2 and cyclin A also control the doubling of centrosomes and thereby co-ordinate this process with the duplication of the genetic material. Because many cancer cells often have aberrant numbers of centrosomes, this finding increases our understanding of how normal cells are keep them in check and how cell division can go wrong in cancer cells.