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Ovulation: a multi-gene, multi-step process

R L Robker1, D L Russell, S Yoshioka

  • 1Department of Molecular and Cellular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA.

Steroids
|December 8, 2000
PubMed

Insights

The luteinizing hormone (LH) surge triggers ovulation by inducing proteases. Progesterone receptor (PR) knockout mice reveal cathepsin L and ADAMTS-1 are crucial for ovulation, highlighting their role in reproductive processes.

Area of Science:

  • Reproductive Biology
  • Molecular Endocrinology
  • Protease Function

Background:

  • Ovulation is a complex process controlled by hormonal signaling, including the luteinizing hormone (LH) surge.
  • The progesterone receptor (PR) plays a critical role in ovulation, as evidenced by infertility in PR knockout (PRKO) mice.
  • Identifying PR target genes is essential for understanding the molecular mechanisms governing ovulation.

Purpose of the Study:

  • To identify progesterone receptor (PR) target genes involved in the ovulatory process.
  • To investigate the role of specific proteases, cathepsin L and ADAMTS-1, in LH-induced ovulation.
  • To utilize PRKO mice as a model to elucidate PR-mediated ovulatory pathways.

Main Methods:

  • Comparative analysis of protease gene expression (MMPs, cathepsin L, ADAMTS-1) in wild-type and PRKO mouse ovaries.
  • Induction of protease expression by the LH surge in preovulatory follicles.
  • Quantification of cathepsin L and ADAMTS-1 mRNA levels in PRKO versus wild-type littermates.

Main Results:

  • Matrix metalloproteinases (MMPs) expression was similar in PRKO and wild-type mice.
  • Cathepsin L and ADAMTS-1 expression were selectively induced by the LH surge in granulosa cells of preovulatory follicles.
  • mRNA levels for cathepsin L and ADAMTS-1 were significantly reduced in PRKO mice compared to wild-type littermates.

Conclusions:

  • Cathepsin L and ADAMTS-1 are novel PR target genes induced by the LH surge.
  • These proteases play a critical role in regulating key steps controlling ovulation.
  • The findings provide new insights into the molecular control of ovulation and female fertility.

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