Spinning disk confocal time-lapse imaging of the first mitosis in a C. elegans embryo expressing GFP-KNL-2. Strain OD31; see Materials and methods. As seen for GFP-CeCENP-A (Video 6), discrete foci of the GFP signal within the nucleus coalesce to form holocentric kinetochore plates during prophase. After nuclear envelope breakdown, chromosomes appear as paired lines and congress to the metaphase plate. At metaphase, sister kinetochores form two lines facing opposite spindle poles. During anaphase, foci of GFP-KNL-2 were seen to form in the spindle area. The video is ∼16 min long, and the frame is ∼30 µm top to bottom. DIC is shown on the right, and GFP is shown on the left. Images were acquired at 10-s intervals (see Materials and methods).
