Spindle movement is attenuated in Myo10 morphants. (a) Stills taken from a short section of a confocal movie of GFP–α-tubulin in a control embryo (Video 1). Time stamps indicate time in minutes and seconds. The metaphase spindle undergoes a sudden movement between t = 1:00 and t = 2:00; this “jerky” rotational movement is characteristic of metaphase spindles in control embryos at embryonic stages 9 and 10. (b) Stills taken from confocal movie of GFP–α-tubulin in a Myo10 morphant (Video 2) at the same embryonic stage as the control embryo in panel a. The morphant spindle, even while still bipolar, displays a much more gradual rotational movement than the control spindle. (c) A graph displaying the rotational movement of a control spindle compared with a Myo10 morphant spindle. The time at which spindles enter metaphase and anaphase or undergo pole fragmentation are indicated by arrows and accompanying labels.