Stuck in the divide

A contractile actin ring does most of the work during cytokinesis, but microtubule-to-membrane anchoring is also needed as two cells pinch away from each other. Tomas et al. (page 813) now show that a protein called annexin 11 may act as a bridge during this last separation event by interacting with both the microtubule-binding CHO1 kinesin-like protein and membranes.

Annexins are Ca²⁺-dependent proteins that function in a variety of cellular processes. The team finds that cells lacking annexin 11 fail to separate during division and die via apoptosis. Annexin 11–depleted cells remained joined via long thin extensions that do not resemble the functional midbodies characteristic of cells going through a normal cytokinesis. Annexin 11 and CHO1 coimmunoprecipitated and colocalized to the midbody in wild-type cells.

Annexin 11...