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Studying Cell Cycle-regulated Gene Expression by Two Complementary Cell Synchronization Protocols
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Studying Cell Cycle-regulated Gene Expression by Two Complementary Cell Synchronization Protocols

Published on: June 6, 2017

Polo kinase controls cell-cycle-dependent transcription by targeting a coactivator protein

Zoulfia Darieva1, Richard Bulmer, Aline Pic-Taylor

  • 1Faculty of Life Sciences, University of Manchester, Michael Smith Building, Oxford Road, Manchester M13 9PT, UK.

Nature
|November 24, 2006
PubMed

Insights

The polo kinase Cdc5p controls cell-cycle-dependent gene expression essential for mitosis. Phosphorylation of Ndd1p by Cdc5p ensures proper expression of key mitotic regulators like CLB2.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Genetics

Background:

  • Polo kinases are vital for eukaryotic cell cycle regulation during mitosis.
  • Controlling gene expression of key regulators is crucial for cell cycle progression.
  • The model eukaryote Saccharomyces cerevisiae is used to study conserved cell cycle mechanisms.

Purpose of the Study:

  • To investigate the role of the polo kinase Cdc5p in cell-cycle-dependent gene expression.
  • To elucidate the mechanism by which Cdc5p regulates mitotic gene expression.
  • To determine the impact of Cdc5p-mediated regulation on cell division.

Main Methods:

  • Investigated the temporal recruitment of Cdc5p to gene promoters.
  • Analyzed the phosphorylation of the Ndd1p protein by Cdc5p.
  • Assessed the expression of cell-cycle-regulated genes (e.g., CLB2, SWI5) in wild-type and mutant strains.
  • Observed cell division phenotypes in the absence of Cdc5p function.

Main Results:

  • Cdc5p is recruited to the promoters of the CLB2 gene cluster during specific cell cycle phases.
  • Cdc5p directly phosphorylates the Ndd1p coactivator within the Mcm1p-Fkh2p-Ndd1p complex.
  • This phosphorylation is essential for the correct temporal expression of G2/M phase genes, including CLB2 and SWI5.
  • Loss of Cdc5p-mediated Ndd1p phosphorylation leads to significant cell division defects.

Conclusions:

  • Cdc5p plays a critical role in regulating cell-cycle-dependent gene expression required for mitosis.
  • The phosphorylation of Ndd1p by Cdc5p is a key mechanism for producing essential mitotic regulators.
  • Polo kinase activity is necessary for both mitotic event orchestration and the production of regulatory proteins, expanding its known functions.

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