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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

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PP2A-B56 regulates Mid1 protein levels for proper cytokinesis in fission yeast

Madeline L Chrupcala1, James B Moseley1

  • 1Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth, Hanover NH.

Biorxiv : the Preprint Server for Biology
|July 9, 2024
PubMed

Insights

The protein phosphatase PP2A-B56 is crucial for cell division by maintaining Mid1 protein levels. Its absence causes asymmetric cell division due to misplaced cytokinetic rings in fission yeast.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Protein phosphorylation regulates cell division, including cytokinesis.
  • The anillin-like protein Mid1 establishes the cell division plane in fission yeast.
  • While kinases regulate Mid1, no phosphatases were known to be involved.

Purpose of the Study:

  • To identify protein phosphatases that regulate Mid1 function in cytokinesis.
  • To elucidate the role of PP2A-B56 in controlling cell division plane and Mid1 levels.

Main Methods:

  • Investigated fission yeast mutants lacking the PP2A-B56 subunit (par1Δ).
  • Assessed cell division symmetry and cytokinetic ring placement.
  • Quantified Mid1 protein levels in wild-type and mutant cells.

Main Results:

  • PP2A-B56 is essential for proper cytokinesis.
  • par1Δ cells exhibit asymmetric division with misplaced cytokinetic rings.
  • Reduced Mid1 protein levels in par1Δ mutants lead to defects at the cytokinetic ring.
  • Restoring Mid1 expression rescues the par1Δ cytokinesis defects.

Conclusions:

  • Identified PP2A-B56 as a novel regulator of cytokinesis through Mid1.
  • Discovered a new pathway where PP2A-B56 promotes Mid1 protein levels for correct cell division.
  • Findings have implications for understanding cytokinesis control in diverse organisms.

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