Aurora B puts chromosomes in their place

Small molecule inhibitors of Aurora B activity, characterized by Hauf et al. (page 281) and Ditchfield et al. (page 267), reveal that the mammalian kinase and its budding yeast counterpart, Ipl1, have similar functions. Without Aurora B, mistakes in kinetochore–chromosome interactions go uncorrected.

Early evidence of a function for the Aurora family in correcting syntelic attachments, those in which both chromatids are attached to the same spindle pole, was provided by the ipl1 mutant. But visualizing spindle–kinetochore attachments in yeast is difficult. The two articles in this issue examine attachments directly, by inhibiting Aurora B in mammalian cells.

The groups used different compounds, but in both cases the Aurora B inhibitors left chromosomes misaligned and compromised the spindle checkpoint, thus causing division failure and endoreduplication. Hauf et al. saw that syntelic attachments...