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Updated: Aug 6, 2025

Meiotic Spindle Assessment in Mouse Oocytes by siRNA-mediated Silencing
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Meiotic Spindle Assessment in Mouse Oocytes by siRNA-mediated Silencing

Published on: October 11, 2015

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Mcrs1 regulates G2/M transition and spindle assembly during mouse oocyte meiosis

Jia-Qian Ju1, Zhen-Nan Pan1, Kun-Huan Zhang1

  • 1College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China.

EMBO Reports
|March 23, 2023
PubMed

Insights

Microspherule protein 1 (Mcrs1) regulates mouse oocyte meiosis by controlling cell cycle progression and spindle formation. Its depletion delays the G2/M transition and disrupts spindle assembly during meiosis I.

Area of Science:

  • Reproductive biology
  • Cellular biology
  • Molecular genetics

Background:

  • Microspherule protein 1 (Mcrs1) is involved in transcriptional regulation during mitosis as part of the NSL and INO80 complexes.
  • The precise roles of Mcrs1 in female meiosis remain largely unexplored.

Purpose of the Study:

  • To investigate the function of Mcrs1 during female meiosis in mouse oocytes.
  • To elucidate Mcrs1's role in regulating the meiotic G2/M transition and spindle assembly.

Main Methods:

  • Mcrs1 depletion in mouse oocytes.
  • Analysis of histone modifications (H4K16ac, H3K4me2, H3K9me2) and protein levels (CDK1, cyclin B1).
  • Assessment of spindle assembly and kinase activities (Aurora kinases, Kif2A).

Main Results:

  • Mcrs1 depletion delays the meiotic G2/M transition by altering HDAC2-mediated histone modifications and reducing CDK1 activity and cyclin B1.
  • Mcrs1 associates with spindle poles and chromosomes during meiosis I.
  • Mcrs1 depletion leads to abnormal spindle assembly due to decreased Aurora kinase and Kif2A activity, indicating a transcription-independent role.

Conclusions:

  • Mcrs1 is a novel regulator of the meiotic G2/M transition and spindle assembly in mouse oocytes.
  • Mcrs1 plays crucial roles in both transcriptional-dependent and -independent pathways governing oocyte meiosis.
Keywords:
G2/M transitionMcrs1meiosisoocytespindle

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