The mitotic spindle plays a key part in determining the site of the cleavage furrow in dividing metazoan cells. But are other mechanisms also involved? Here evidence is provided for a spindle-independent pathway for furrow positioning that occurs during asymmetric divisions of Drosophila neuroblast cells. The pathway involves the Pins protein complex, which polarizes furrow-forming proteins to the basal cortex of the cell. This mechanism might also occur in other highly polarized cell types.
- Clemens Cabernard
- Kenneth E. Prehoda
- Chris Q. Doe
