Localization of myosin-GFP and Kinesin-6–GFP (Pav-GFP) in cells with monopolar spindles. Monopolar spindles were induced by RNAi depletion of the Kinesin-5 motor (Klp61F in Drosophila); cells also were treated with dsRNA for BubR1, which causes these monopolar cells to bypass the spindle assembly checkpoint and proceed into anaphase. Cells were coexpressing mCherry-tubulin along with myosin-GFP (A) or Kinesin-6–GFP (B) and imaged by dual-color TIRF microscopy (note that different cells are shown in A and B). Both cells have asymmetric monopolar spindles, with most microtubules projecting toward one side of the cell. In A and B, myosin-GFP and Kinesin-6–GFP accumulate at the regions of microtubule plus ends during anaphase. See Videos 9 (myosin-GFP) and 5 (Kinesin-6–GFP). Bars, 10 µm.