Flying the cell division plane

Establishing the plane in which a cell divides is a vital step during development and cell differentiation. Microtubules are important components of this cell division, but how they control the position of the division plane (furrow) remains unclear. The current paradigm suggests that a bipolar microtubule array is required to position the furrow during division, with microtubules promoting furrowing by means of overlapping from opposite poles or by microtubule asters restricting furrowing at the cell poles. Both these models dictate that bipolar arrays of microtubules must always be present. However, in the August 7 Nature, Julie C. Canman and colleagues at the University of North Carolina reveal that a bipolar spindle is not absolutely required for furrow formation and that microtubule dynamics may be responsible for positioning the division plane (Nature, DOI:10.1038/nature01860, August 6, 2003).

Canman et al. created monopolar half-spindles in PtK1 cells through the...