Insights into structure-function correlations of ungulate seminal plasma proteins

Area of Science:

• Reproductive Biology
• Protein Chemistry
• Mammalian Physiology

Background:

• Mammalian seminal plasma contains factors crucial for sperm function, including decapacitation factors and proteins enhancing fertilizing potential.
• Sperm capacitation involves conserved membrane remodeling events, but different seminal plasma proteins mediate this process across species.

Purpose of the Study:

• To explore the role of seminal plasma proteins in mammalian sperm capacitation and fertilization.
• To investigate the species-specific functions of major seminal plasma protein families, particularly spermadhesins and Fn2-choline-binding proteins in ungulates.

Main Methods:

• Biochemical and biophysical studies of seminal plasma proteins.
• Determination of crystal structures of key proteins like porcine and bovine spermadhesins and bull PDC-109.

Main Results:

• Seminal plasma proteins, especially spermadhesins and Fn2-choline-binding proteins, are vital in ungulate fertilization.
• While sperm capacitation mechanisms are conserved, specific proteins exert species-specific effects on sperm physiology.
• Structural insights into porcine, bovine spermadhesins, and bull PDC-109 reveal molecular bases for their roles.

Conclusions:

• Seminal plasma proteins play a critical, species-specific role in mammalian fertilization.
• Structural and functional diversity of proteins like spermadhesins contributes to species-specific sperm capacitation.
• Understanding these proteins offers insights into the molecular mechanisms of fertilization.