Exploring boar sperm sialylation during capacitation using boronic acid-functionalized beads.

Area of Science:

• Reproductive Biology
• Glycobiology
• Biochemistry

Background:

• Sialic acid (SA) is crucial for mammalian sperm function during fertilization.
• Boronic acid offers high affinity and specificity for SA detection compared to other methods.

Purpose of the Study:

• To investigate the surface sialylation profile of boar sperm using boronic acid carriers.
• To identify sialoglycoproteins involved in boar sperm capacitation.

Main Methods:

• Utilized 3-aminophenylboronic acid-labeled fluorescent latex (CML-APBA) for visualizing SA distribution.
• Employed magnetic beads (CMM-APBA) for immunoprecipitation of sialoglycoproteins.
• Analyzed sperm sialylation patterns before and after in vitro capacitation using flow cytometry.

Main Results:

• Identified three primary binding regions for CML-APBA on ejaculated boar sperm heads.
• Observed distinct sialylation patterns on sperm heads after in vitro capacitation.
• Demonstrated a decrease in overall sperm membrane sialylation levels post-capacitation.
• Identified AWN and PSP-1, known decapacitation factors, as reduced sialoglycoproteins after capacitation.

Conclusions:

• Boronic acid carriers effectively map boar sperm surface sialylation.
• Capacitation alters sperm sialylation patterns and reduces overall SA levels.
• The decrease in AWN and PSP-1 during capacitation may correlate with reduced sperm sialylation.