Curr. Biol. 19, 1086–1095 (2009)

By squishing cells, researchers hope to better understand the dynamics of their division. Several competing models have been proposed for the mechanics of the cell's spindle — an assembly of microtubules and other structures that stretches across dividing cells and splits chromosomes between them.

Timothy Mitchison and Sophie Dumont of Harvard Medical School placed dividing cells in an apparatus that gently clamps down on them. The spindles in squashed cells got longer and wider, returning to their normal dimensions after the force was released.

On the basis of their observations, the authors propose that a mechanochemical switch exists at the spindle poles that regulates microtubule length in response to forces within the spindle.