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Updated: Sep 19, 2025

Meiotic Spindle Assessment in Mouse Oocytes by siRNA-mediated Silencing
09:16

Meiotic Spindle Assessment in Mouse Oocytes by siRNA-mediated Silencing

Published on: October 11, 2015

11.8K

MPS1 promotes timely spindle bipolarization to prevent kinetochore-microtubule attachment errors in oocytes

Shuhei Yoshida1, Reiko Nakagawa2, Kohei Asai3,4

  • 1Laboratory for Chromosome Segregation, RIKEN Center for Biosystems Dynamics Research (BDR), Kobe, Japan. shuhei.yoshida@riken.jp.

The EMBO Journal
|June 4, 2025
PubMed

Insights

Mitotic Centrosome Protein 1 (MPS1) kinase ensures correct chromosome segregation in mouse oocytes by promoting timely spindle bipolarization before stable kinetochore-microtubule attachment, preventing aneuploidy.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Genetics

Background:

  • Incorrect kinetochore-microtubule attachment causes chromosome segregation errors.
  • Acentrosomal oocytes face high risk due to random microtubule orientation before spindle bipolarization.

Purpose of the Study:

  • Investigate the regulation of spindle bipolarization and kinetochore-microtubule attachment timing in acentrosomal oocytes.
  • Determine the role of MPS1 kinase in this process.

Main Methods:

  • Utilized mouse oocytes.
  • Investigated the function of MPS1 kinase through inhibition experiments.
  • Observed kinetochore-microtubule attachment and spindle bipolarization dynamics.

Main Results:

  • MPS1 kinase promotes timely spindle bipolarization before stable kinetochore-microtubule attachment.
  • Inhibition of MPS1 delays spindle bipolarization, making it dependent on stable attachments.
  • Delayed bipolarization leads to incorrect kinetochore-microtubule attachments.

Conclusions:

  • Propose a two-step kinetochore-based model for acentrosomal spindle assembly.
  • Unstable and stable microtubule attachment states sequentially regulate spindle formation.
  • This mechanism reduces the risk of egg aneuploidy.
Keywords:
KinetochoreMicrotubuleOocyteSpindle

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