Fig. 2. Ssm4p is essential for the horsetail movement in fission yeast. Nuclei of conjugated cells were monitored and the fluorescence of the artificial nuclear marker GST-NLS-GFP was followed. (A) Nuclear behaviour in living wild type, dhc1 and ssm4 strains. Serial images were obtained from a single cell at meiotic prophase. The numbers on the left indicate time span in minutes. (B) Time-lapse recording of a nucleus in a wild-type cell and a ssm4 cell undergoing meiosis. The numbers on the left indicate the time from the nuclear fusion in minutes. Bars, 10 µm. (C) Diploid wild-type and ssm4 cells were cultured to late log phase, synchronously induced to meiosis at 30°C by depleting nitrogen from the medium. The number of nuclei was counted at the times indicated. More than 200 cells were examined at each time point. Open circles, open squares, open triangles indicate percentage of cells with one nucleus, two nuclei and three or four nuclei, respectively.