© S. L. Forsburg .
This comes from our study on fission yeast Rdh54 (Catlett & Forsburg 2003.)In all cases, movies show the nuclei of zygotes labeled with NLS-GFP (GFP with a nuclear localization sequence). This method has been used for live-cell analysis of meiosis by Molnar et al (2001), Live observation of fission yeast meiosis in recombination-deficient mutants: a study on achiasmate chromosome segregation. J Cell Sci. 114:2843-53.
In these films, all movies begin with zygotes in the horsetail stage of meiosis prior to entry into meiotic prophase and continue through the MII division (or through the time required for an MII division to occur). Images were collected every 5 minutes over 5-6 hours. In all cases, both GFP and phase are observed. False color was assigned as indicated for each film.
Format: Movies are in quicktime format. A free player is available for both Macintosh and Windows platforms.
wild-type:
Cross of two wild-type haploids with NLS-GFP shown in green and DIC/Normarski in red. Images collected every 5 min and playback at 10 frames/sec. Approximate total elapsed time of six hours forty minutes. Note that two distinct meiotic divisions occur to produce four equal sized GFP signals (=spores).
rdh54/tid1, normal:
Cross of two rdh54/tid1 haploids with NLS-GFP shown in red and DIC/Normarski in green. Images collected every 5 min and playback at 10 frames/sec. Approximate total elapsed time of almost five hours. In this example (which represents about 60% of the population), presence of tid1 does not greatly disrupt divisions and four equal sized GFP signals (=spores) are produced.
rdh54/tid1 abberant:
Cross of two rdh54/tid1 haploids with NLS-GFP shown in red and DIC/Normarski in green. Images collected every 5 min and playback at 10 frames/sec. Approximate total elapsed time of almost five hours. In this example, tid1 results in abberant divisions and greater than four GFP signals appear after the divisions. However, two distinct divisions occur and it initially appears that each segregation is approximately even.
rdh54 rhp54 double mutant:
Cross of two rdh54/tid1 rhp54 haploids with NLS-GFP shown in green and DIC/Normarski in red. Images collected every 5 min and playback at 10 frames/sec. Approximate total elapsed time of five hours. Middle zygote: The first meiotic division is quite abberant, with nearly all of the nucleus segrating upward, only a very small GFP signal moves to the opposite end of the ascus. A second meiotic division ensues resulting in six GFP signals.
© S. L. Forsburg .