Clustering creates a spindle

Individual lobbyists might have a hard time promoting their cause, but get a large group of like-minded individuals together, and there's action. Similarly, the spindle assembly action of Aurora B starts only once this kinase comes together with other chromosomal passenger complex (CPC) members, according to a new study by Alexander Kelly, Hironori Funabiki, and colleagues (Rockefeller University, New York, NY).

Spindle assembly at the chromosomes is controlled by the Aurora B kinase, which deactivates microtubule-destructing proteins MCAK and Op18. The CPC member Dasra A is required for the rest of the CPC to assemble on chromosomes. Kelly et al. now show that this chromosomal loading serves to cluster the CPC components. It is this clustering that then kicks off the Aurora B pathway.

The team induced clustering of the...