Proacrosin activation mechanisms in capacitated and frozen-thawed boar spermatozoa

The main objective of the current study was to explore the different activation mechanisms of capacitation and freeze-thawed spermatozoa. Using SDS-PAGE and Western blotting, the conversion process of boar proacrosin during freeze-thawing and capacitation of spermatozoa was analyzed. The results revealed that capacitated spermatozoa exhibited a greater fluorescence area than that of the freeze-thawed spermatozoa, which were smaller than those of the fresh group. Fresh spermatozoa displayed 45- and 35- kDa protein bands, while those of freeze-thawed andcapacitated spermatozoa displayed 45-, 35- and 28-kDa bands. In summary, these data indicate that proacrosin is activated, thus becoming α- and β-acrosins and a 28-kDa protein during capacitation and freeze-thawing.