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Spatiotemporal Analysis of Cytokinetic Events in Fission Yeast
11:19

Spatiotemporal Analysis of Cytokinetic Events in Fission Yeast

Published on: February 20, 2017

Interaction of Cdc2 and Cdc18 with a fission yeast ORC2-like protein

J Leatherwood1, A Lopez-Girona, P Russell

  • 1Department of Molecular Biology, Scripps Research Institute, La Jolla, California 92037, USA.

Nature
|January 25, 1996
PubMed

Insights

Fission yeast Cdc2 kinase interacts with Orp2, a protein essential for DNA replication initiation. This interaction suggests conserved eukaryotic origin recognition complex (ORC) functions and Cdc2

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Genetics

Background:

  • Cdc2 kinase regulates DNA replication in fission yeast, controlling entry into S phase and preventing re-initiation.
  • The origin recognition complex (ORC) binds chromosomal origins, initiating DNA replication.
  • Orp2 is a protein similar to Orc2, a subunit of Saccharomyces cerevisiae ORC.

Purpose of the Study:

  • To investigate the interaction between Cdc2 kinase and Orp2 in fission yeast.
  • To elucidate the role of Orp2 in DNA replication and cell cycle control.
  • To provide evidence for conserved eukaryotic ORC functions and Cdc2's role in replication initiation.

Main Methods:

  • Protein interaction studies (e.g., yeast two-hybrid, co-immunoprecipitation).
  • Analysis of DNA replication and cell cycle progression in wild-type and mutant fission yeast strains.
  • Investigation of mitotic progression and checkpoint signaling.

Main Results:

  • Cdc2 kinase interacts with Orp2, a protein homologous to Orc2.
  • Fission yeast Orp2 is essential for DNA replication and interacts with Cdc18, a replication activator.
  • Cells lacking Orp2 exhibit aberrant mitosis, suggesting a role in checkpoint signaling.

Conclusions:

  • Fission yeast Orp2 is crucial for DNA replication initiation and cell cycle progression.
  • The findings support conserved functions of origin recognition complex (ORC) across eukaryotes.
  • Cdc2 kinase likely controls DNA replication initiation by directly acting at chromosomal origins.

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