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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

Fission yeast MO25 protein is localized at SPB and septum and is essential for cell morphogenesis

Muneyoshi Kanai1, Kazunori Kume, Kohji Miyahara

  • 1Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, Higashi Hiroshima, Japan.

The EMBO Journal
|August 13, 2005
PubMed

Insights

A novel network involving Pmo25, Nak1, Mor2, and Orb6 proteins controls cell morphogenesis and polarity in fission yeast. This pathway links the septation initiation network (SIN) to cell division and separation processes.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Genetics

Background:

  • Cell morphogenesis is crucial for eukaryotic development, differentiation, and proliferation.
  • Fission yeast Mor2 and Orb6 kinase are vital for cell polarity, with mutations causing polarity loss.

Purpose of the Study:

  • To elucidate the roles of conserved proteins Pmo25, Nak1, Mor2, and Orb6 in cell morphogenesis and polarity control.
  • To investigate the functional interactions within this protein network and its connection to other cellular pathways.

Main Methods:

  • Protein localization studies using microscopy.
  • Co-immunoprecipitation to assess protein complex formation.
  • Kinase activity assays.
  • Genetic analysis of mutant phenotypes.

Main Results:

  • Pmo25, Nak1, Mor2, and Orb6 form a morphogenesis network essential for polarity and cell separation.
  • Pmo25 localizes to spindle pole bodies and translocates during cytokinesis, forming a complex with Nak1.
  • Pmo25 is required for Nak1 localization and activity, and both are essential for Orb6 kinase activity.
  • The septation initiation network (SIN) kinases Cdc7 and Sid1 regulate Pmo25 localization and Nak1-Orb6 activity.

Conclusions:

  • A conserved protein network (Pmo25, Nak1, Mor2, Orb6) is critical for fission yeast cell morphogenesis, polarity, and separation.
  • This network exhibits a functional linkage with the septation initiation network (SIN), integrating cell division and morphogenesis pathways.

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