| Autor: |
Lindgren, Anne, Bungard, David, Pierce, Michael, Xie, Jianxin, Vershon, Andrew, Winter, Edward |
| Předmět: |
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| Zdroj: |
EMBO Journal; 12/1/2000, Vol. 19 Issue 23, p6489-6497, 9p |
| Abstrakt: |
Saccharomyces cerevisiae mutants that fail to complete meiotic recombination are blocked by the RAD17/RAD2d/MEC1 checkpoint signaling pathway in pachytene when early sporulation genes are expressed. Middle genes are not activated in checkpoint-arrested cells because the Ndt80 transcription factor is inhibited. We find that the pachytene checkpoint requires Suml, a transcriptional repressor that recognizes a subset of Ndt80-binding sites. Mutants lacking Suml or Rad17 partially bypass the block to the nuclear divisions but do not form spores, while mutants lacking both Suml and Radl7 completely bypass the block and form morphologically normal spores. The level of Sum1 protein decreases as middle genes are expressed, and this decrease is blocked in checkpoint-arrested cells. These data suggest that Sum1 levels are regulated by the checkpoint and that progression of the meiotic divisions and spore differentiation can be differentially controlled by competition of the Suml repressor and Ndt80 activator for occupancy at key middle promoters. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
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