Tension directly stabilizes reconstituted kinetochore-microtubule attachments

The kinetochore is the large protein complex that assembles on centromeric DNA to mediate chromosome separation. For decades, researchers have tried to isolate whole functional kinetochores without success. Sue Biggins and colleagues now report the first purification of functional kinetochores. They also show that kinetochore particles maintain load-bearing associations with assembling and disassembling microtubules, and that tension directly increases the lifetimes of the attachments. These results provide evidence that tension selectively stabilizes kinetochore–microtubule interactions.