Arrdc4-dependent extracellular vesicle biogenesis is required for sperm maturation

Area of Science:

• Reproductive Biology
• Cell Biology
• Molecular Biology

Background:

• Extracellular vesicles (EVs) mediate cell-to-cell communication in reproductive systems.
• The functional role of EVs in male reproductive tract and sperm function remains under investigation.
• Arrdc4, an alpha-arrestin family protein, is implicated in EV biogenesis and release.

Purpose of the Study:

• To investigate the role of Arrdc4-mediated extracellular vesicle biogenesis in sperm function.
• To determine if Arrdc4 is essential for sperm maturation and fertilization capabilities.

Main Methods:

• Analysis of sperm from Arrdc4 knockout mice.
• Assessment of sperm motility, acrosome reaction, and zona pellucida binding.
• Quantification of EV production by epididymal epithelial cells.
• Supplementation of Arrdc4 sperm with exogenous EVs.

Main Results:

• Sperm from Arrdc4 mice exhibited normal testicular development but impaired epididymal maturation.
• Defects in Arrdc4 sperm included reduced motility, premature acrosome reaction, and decreased zona pellucida binding.
• Reduced EV production was observed in Arrdc4 epididymal epithelial cells.
• Supplementation with EVs partially rescued the acrosome reaction defect and restored zona pellucida binding in Arrdc4 sperm.

Conclusions:

• Arrdc4-mediated EV biogenesis is essential for proper sperm maturation in the epididymis.
• Arrdc4 plays a critical role in regulating sperm function through the control of EV production.