Protein analysis of boar seminal plasma proteins with protective effect during low-temperature storage of spermatozoa

The present study aimed to investigate the effect of different seminal plasma proteins (SPPs) on boar spermatozoa functional characteristics. We investigated the putative protective effect of SSPs on sperm cells motility and velocity, as well as on the integrity of the plasma membrane (PM) during low-temperature storage at 4 °C. SPPs fractions were obtained and purified by gel permeation chromatography (GPC). Nine fractions of SPPs were obtained and further characterized by 12% sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Sperm computer analysis (SCA) after incubation of spermatozoa with separated proteins revealed that fraction 6 consisting of low molecular weight (MW) proteins could preserve spermatozoa motility and velocity better when compared to those with higher MW. Two-dimensional (2D) elecrtophoretic analysis showed that fraction 6 contained proteins with the following MW and isoelectric point (pI): 16 kDa and pI 7.35, 18 kDa and pI 5.20, 19 kDa and pI 7.35, 26 kDa and pI 4.50, 26 kDa and pI 4.30, 29 kDa and pI 5.85.