Related Experiment Video

Updated: Jan 14, 2026

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

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Phosphoproteomic identification of Mos-MAPK targets in meiotic cell cycle and asymmetric oocyte divisions

Ivan Avilov1, Yehor Horokhovskyi2, Pooja Mehta1

  • 1Research Group Cytoskeletal Dynamics in Oocytes, Max Planck Institute for Multidisciplinary Sciences , Göttingen, Germany.

The Journal of Cell Biology
|October 22, 2025
PubMed

Insights

Mos-MAPK signaling controls oocyte meiosis by regulating mRNA translation and cytoskeletal dynamics. This kinase acts as a critical switch between cell division programs, ensuring proper meiotic progression and polar body size.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Developmental Biology

Background:

  • The Mos kinase activates the ERK/MAPK pathway, crucial for oocyte meiosis across metazoa.
  • Molecular targets of Mos-MAPK are largely unknown, hindering understanding of its regulatory roles.

Purpose of the Study:

  • To identify molecular targets of Mos-MAPK in starfish oocytes.
  • To elucidate the mechanisms by which Mos-MAPK controls meiotic progression and cell division asymmetry.

Main Methods:

  • Utilized starfish oocytes for cellular assays and phosphoproteomics.
  • Combined phosphoproteomic analysis with cellular assays to identify Mos-MAPK targets.

Main Results:

  • Identified CPE-mediated mRNA polyadenylation as a key Mos-MAPK target, with translation essential for the second meiotic division.
  • Revealed cytoskeletal regulators as Mos-MAPK targets, critical for asymmetric meiotic divisions by reducing astral microtubule growth.
  • Demonstrated Mos-MAPK regulation ensures spindle positioning and minimizes polar body size.

Conclusions:

  • Mos-MAPK orchestrates meiotic progression through mRNA translation and cytoskeletal regulation.
  • Phosphoproteomics identified key molecular modules controlled by Mos-MAPK.
  • Mos-MAPK acts as a conserved switch between mitotic and meiotic division programs.

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