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Updated: May 29, 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

Serum- and Glucocorticoid-Regulated Kinase 1 Regulates Spindle Assembly Through RanBP1 During Oocyte Meiosis

Li-Shu Li1, Shu-Jie Yang2, Xiao-Qing Li2

  • 1Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, Jiangsu, China.

Journal of Cellular Physiology
|May 28, 2026
PubMed

Insights

Serum- and glucocorticoid-regulated kinase 1 (SGK1) is crucial for mammalian oocyte maturation. Its downregulation impairs spindle assembly and meiotic progression, potentially contributing to age-related infertility.

Area of Science:

  • Reproductive Biology
  • Cell Biology
  • Molecular Genetics

Background:

  • Advanced maternal age correlates with increased oocyte aneuploidy and miscarriage.
  • Serum- and glucocorticoid-regulated kinase 1 (SGK1) is downregulated in oocytes from aged mice, but its role in maturation is unknown.

Purpose of the Study:

  • To elucidate the mechanisms by which SGK1 regulates oocyte maturation and meiotic progression.

Main Methods:

  • SGK1 localization studies in mouse oocytes.
  • SGK1 knockdown using siRNA and pharmacological inhibition.
  • Analysis of spindle assembly, kinetochore-microtubule attachments, and meiotic progression.
  • Investigation of potential mediators like RanBP1.
  • Comparative studies in porcine oocytes.

Main Results:

  • SGK1 localizes to spindle poles during oocyte maturation.
  • SGK1 inhibition disrupts spindle assembly and kinetochore-microtubule attachments.
  • This leads to spindle assembly checkpoint activation, failed degradation of Cyclin B1 and Securin, and impaired meiotic transition.
  • RanBP1 is identified as a potential SGK1 mediator.
  • Similar defects observed in porcine oocytes, indicating conserved function.

Conclusions:

  • SGK1 is essential for proper spindle assembly and meiotic progression in mammalian oocytes.
  • Dysregulation of SGK1 may contribute to infertility associated with advanced maternal age.
  • SGK1's role in oocyte maturation is conserved across mammalian species.
Keywords:
Cyclin B1SACSGK1chromosomesspindle assembly

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