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CDC20 downregulation impairs spindle morphology and causes reduced first polar body emission during bovine oocyte

W L Yang1, J Li2, P An2

  • 1College of Veterinary Medicine, Northwest A&F University, Yangling, P. R. China; Shaanxi Center of Stem Cell Engineering & Technology, Yangling, P. R. China; Department of Life Science and Technology, Ningxia Polytechnic, Yinchuan, P. R. China.

Theriogenology
|December 24, 2013
PubMed

Insights

Cell division cycle protein 20 (CDC20) is crucial for bovine oocyte maturation. Downregulating CDC20 impairs spindle assembly and chromosomal segregation, preventing first polar body emission.

Area of Science:

  • Reproductive Biology
  • Cell Biology
  • Molecular Biology

Background:

  • Cell division cycle protein 20 (CDC20) regulates cell division.
  • The function of CDC20 in bovine oocyte maturation is not well understood.

Purpose of the Study:

  • To investigate the role of CDC20 in bovine oocyte maturation.
  • To determine CDC20's involvement in meiotic progression and first polar body extrusion.

Main Methods:

  • CDC20 morpholino antisense oligonucleotides (MOs) were microinjected into bovine oocytes to suppress CDC20 expression.
  • Oocytes were analyzed for meiotic progression, spindle formation, and chromosomal segregation.

Main Results:

  • CDC20 downregulation significantly reduced first polar body emission.
  • Oocytes exhibited meiotic arrest at or before meiotic stage I with abnormal spindles.
  • Newly synthesized CDC20 was not essential for the meiosis II-to-anaphase II transition.

Conclusions:

  • CDC20 is essential for proper spindle assembly and chromosomal segregation during bovine oocyte maturation.
  • CDC20 plays a critical role in the extrusion of the first polar body.
Keywords:
Bovine oocyte maturationCDC20 downregulationSpindle morphology

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