Microtubules, membranes and cytokinesis.

Proper division of the cell requires coordination between chromosome segregation by the mitotic spindle and cleavage of the cell by the cytokinetic apparatus. Interactions between the mitotic spindle, the contractile ring and the plasma membrane ensure that the cleavage furrow is properly placed between the segregating chromosomes and that new membrane compartments are formed to produce two daughter cells. The microtubule midzone is able to stimulate the cortex of the cell to ensure proper ingression and completion of the cleavage furrow. Specialized microtubule structures are responsible for directing membrane vesicles to the site of cell cleavage, and vesicle fusion is required for the proper completion of cytokinesis.