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Abstract Meiosis in the budding yeast Saccharomyces cerevisiae is used to create haploid yeast spores from a diploid mother cell. During meiosis II, cytokinesis occurs by closure of the prospore membrane, a membrane that initiates at the spindle pole body and grows to surround each of the haploid meiotic products. Timely prospore membrane closure requires SPS1, which encodes an STE20 family GCKIII kinase. To identify genes that may activate SPS1, we utilized a histone phosphorylation defect of sps1 mutants to screen for genes with a similar phenotype and found that cdc15 shared this phenotype. CDC15 encodes a Hippo-like kinase that is part of the mitotic exit network. We find that Sps1 complexes with Cdc15, that Sps1 phosphorylation requires Cdc15, and that CDC15 is also required for timely prospore membrane closure. We also find that SPS1, like CDC15, is required for meiosis II spindle disassembly and sustained anaphase II release of Cdc14 in meiosis. However, the NDR-kinase complex encoded by DBF2/DBF20MOB1 which functions downstream of CDC15 in mitotic cells, does not appear to play a role in spindle disassembly, timely prospore membrane closure, or sustained anaphase II Cdc14 release. Taken together, our results suggest that the mitotic exit network is rewired for exit from meiosis II, such that SPS1 replaces the NDR-kinase complex downstream of CDC15.
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Meiosis II spindle disassembly requires two distinct pathways
AMA1 and SPS1 control distinct aspects of meiosis II spindle disassembly, with AMA1 affecting the loss of Ase1 and Cin8 during meiosis II spindle disassembly, while SPS1 affects Bim1. The Anaphase Promoting Complex and meiotic/mitotic exit pathways seem to regulate similar targets in meiosis as mitosis, despite utilizing meiosis-specific regulators in those pathways.
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- Award ID(s):
- 1950051
- PAR ID:
- 10497111
- Editor(s):
- Bloom, Kerry
- Publisher / Repository:
- American Society for Cell Biology (ASCB)
- Date Published:
- Journal Name:
- Molecular Biology of the Cell
- Volume:
- 34
- Issue:
- 10
- ISSN:
- 1059-1524
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1091/mbc.E23-03-0096
