Altering the orientation of contact between these cells alters the axis along which the mitotic spindle is established, and hence the orientation of cell division.
Orientation requires cell contact ten minutes before cytokinesis begins.
No rotation occurs in nocodazole-treated cell pairs. Additional results suggest that in the EMS cell, spindle orientation ensures that cleavage occurs in a plane which will partition developmental information, received by induction, to one of EMS's daughters cells.