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07:38
Measuring In Vitro ATPase Activity for Enzymatic Characterization
Published on: August 23, 2016
Functional studies of eppin
Michael G O'Rand1, Esther E Widgren, Katherine G Hamil
1Department of Cell and Developmental Biology and Laboratories for Reproductive Biology, University of North Carolina at Chapel Hill, NC 27599, USA. morand@unc.edu
Biochemical Society Transactions
|September 23, 2011
Summary
Epididymal protease inhibitor (eppin) is crucial for male fertility by regulating sperm motility. Inhibiting eppin-semenogelin interaction offers a promising avenue for reversible male contraception.
Area of Science:
- Reproductive biology
- Molecular endocrinology
- Protein biochemistry
Background:
- Epididymal protease inhibitor (eppin) is a novel protein identified on human chromosome 20q12-13.2.
- EPPIN is secreted by Sertoli and epididymal epithelial cells, existing as dimers and multimers, and complexes with lactotransferrin and clusterin on sperm surfaces.
- SEMG (semenogelin) binding to the eppin complex during ejaculation initiates key functional events.
Purpose of the Study:
- To characterize the novel epididymal protease inhibitor (eppin) and elucidate its functions in male reproductive physiology.
- To investigate the role of eppin in modulating prostate-specific antigen (PSA) activity, providing antimicrobial protection, and regulating sperm motility.
- To assess the contraceptive potential of targeting eppin-SEMG interactions.
Main Methods:
- Gene characterization and protein analysis of EPPIN.
- In vivo studies involving immunization of male monkeys with recombinant eppin.
- Development of compounds targeting the eppin-SEMG interaction.
Main Results:
- EPPIN is a 133-amino acid cysteine-rich protein with Kunitz-type and WAP-type sequences.
- EPPIN modulates PSA activity, offers antimicrobial protection, and inhibits sperm motility by binding SEMG.
- Immunization with recombinant eppin induced reversible contraception in male monkeys.
- Compounds inhibiting eppin-SEMG interaction were developed.
Conclusions:
- EPPIN is essential for male fertility, playing a critical role in regulating sperm function post-ejaculation.
- Targeting the eppin-SEMG interaction presents a viable strategy for developing novel male contraceptive agents.
- Further development of eppin-inhibiting compounds holds significant potential for male birth control.
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