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Published on: February 26, 2018

Cystathionine beta synthase participates in murine oocyte maturation mediated by homocysteine

Rong Liang1, Wei-Dong Yu, Jun-Bao Du

  • 1Department of Pediatrics, Peoples Hospital, Peking University, 11# South Street, Beijing, China.

Reproductive Toxicology (Elmsford, N.Y.)
|June 15, 2007
PubMed

Insights

Cystathionine beta synthase (CBS) is crucial for oocyte maturation. Suppressing CBS in granulosa cells increases immature oocytes, suggesting CBS regulates maturation via homocysteine levels.

Area of Science:

  • Reproductive Biology
  • Biochemistry
  • Cellular Biology

Background:

  • Cystathionine beta synthase (CBS) is highly expressed in the cumulus-oocyte complex during ovulation.
  • The precise role of CBS in oocyte maturation is not fully understood.

Purpose of the Study:

  • To investigate the role of cystathionine beta synthase (CBS) in mammalian oocyte maturation.
  • To determine if CBS influences oocyte maturation through regulating homocysteine levels.

Main Methods:

  • Utilized small-interfering RNA (siRNA) to selectively deplete CBS mRNA and protein in murine granulosa cells.
  • Assessed CBS depletion using semi-quantitative reverse-transcriptase PCR (RT-PCR) and immunofluorescence staining.
  • Evaluated oocyte maturation rates in vitro using medium conditioned by CBS-suppressed granulosa cells.

Main Results:

  • Functional suppression of CBS in granulosa cells led to a significant increase in germinal vesicle (GV)-arrested oocytes.
  • CBS depletion was confirmed by reduced CBS mRNA and protein levels.
  • Homocysteine levels gradually increased in the medium from transfected granulosa cells.

Conclusions:

  • Cystathionine beta synthase (CBS) plays a significant role in the process of oocyte maturation.
  • CBS may exert its effect by modulating homocysteine levels in the oocyte's microenvironment.
  • This study provides evidence for CBS involvement in maintaining oocyte meiotic competence.

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