The chromosomal passenger complex (CPC): from easy rider to the godfather of mitosis

The chromosomal passenger complex (CPC), which is formed by inner centromere protein (INCENP), borealin, survivin and Aurora B kinase, targets to different locations at different times during mitosis. As it regulates key events at each of these locations, the CPC can be considered as a master regulator of mitosis. Successful cell division requires the precise and timely coordination of chromosomal, cytoskeletal and membrane trafficking events. These processes are regulated by the competing actions of protein kinases and phosphatases. Aurora B is one of the most intensively studied kinases. In conjunction with inner centromere protein (INCENP), borealin (also known as Dasra) and survivin it forms the chromosomal passenger complex (CPC). This complex targets to different locations at differing times during mitosis, where it regulates key mitotic events: correction of chromosome–microtubule attachment errors; activation of the spindle assembly checkpoint; and construction and regulation of the contractile apparatus that drives cytokinesis. Our growing understanding of the CPC has seen it develop from a mere passenger riding on the chromosomes to one of the main controllers of mitosis.