PRSS38 Is a Novel Sperm Serine Protease Involved in Human and Mouse Fertilization

Area of Science:

• Reproductive Biology
• Biochemistry
• Genetics

Background:

• Sperm proteases play key roles in gamete interaction during fertilization.
• The serine protease PRSS38's function in mammalian fertilization is not fully understood.

Purpose of the Study:

• To analyze the expression, localization, and function of serine protease PRSS38 in human and mouse sperm.
• To investigate PRSS38's involvement in fertilization-related events and its potential link to male infertility.

Main Methods:

• Bioinformatics (genomics, protein modeling, variant analysis)
• Cellular and biochemical assays (Western immunoblotting, immunocytochemistry)
• Functional assays (Cumulus Penetration Assay, Human Hemizona Assay, Sperm Penetration Assay, in vitro fertilization)

Main Results:

• PRSS38 was detected and localized in human (acrosomal region, equatorial segment, flagellum) and mouse (equatorial segment, hook) sperm.
• Antibodies against PRSS38 inhibited human sperm-oocyte interactions and mouse in vitro fertilization.
• Genetic variants potentially affecting PRSS38 function were identified.

Conclusions:

• PRSS38 is a GPI-anchored serine protease essential for mammalian fertilization.
• PRSS38 plays a critical role in sperm-oocyte interaction.
• Altered PRSS38 function may contribute to male infertility.