Fig. 3. Nuclear movement is abnormal during the horsetail phase in mcp6 cells. (A) Profiles of the meiotic progression in pat1 (JZ670) and pat1 mcp6 (TT405) diploid cells (azygotic meiosis). The progression of meiosis was monitored every 30 minutes (3-7 hours) or 1 hour (0-2 hours and 7-8 hours) after the temperature shift, depending on the phase of meiosis. At least 200 cells were counted under a microscope to assess the frequencies of Hoechst-33342-stained cells that bear a horsetail, one nucleus, two nuclei and more than three nuclei. Each point denotes the average value of at least three independent experiments. Standard deviations are indicated as error bars. (B) Time-lapse images of pat1 and pat1 mcp6 diploid cells during meiosis I. The nuclei were stained with Hoechst 33342. Images of a single cell were obtained at 2.5-minute intervals. The numbers at the bottom of each photograph represent the timing in minutes, with 0 minute being 2 hours after temperature shift to induce azygotic meiosis. Bar, 5 µm. (C) Time-lapse observation of wild-type (WT) (CT026-1) and mcp6 (ST193) cells during meiosis I. The nuclei were visualized by the fluorescence of a Pol-GFP fusion construct. Images of a single cell were obtained at 5 minute intervals. The numbers at the bottom of each photograph represent the timing in minutes, with 0 minutes being when nuclear fusion (karyogamy) occurs. The white arrowheads indicate the putative trailing edge of the moving nucleus. Bar, 5 µm. (D) The duration of meiotic prophase, meiosis I (MI) and meiosis II (MII) in mcp6 and WT cells. The average values were calculated from ten independent cells observed under a microscope. Standard deviations are shown as error bars.