Localization of the Mm.87328, Mm.386907 and Mm.157049 proteins. (A) Testicular cells, and sperm from cauda epididymis and vas deferens were (+) or were not (-) treated with biotin or trypsin and then subjected to western blot analysis. ADAM2, known to be located at the sperm surface, was included as a control. TC, testicular (spermatogenic) cells; S, mature sperm from the epididymis and vas deferens. ADAM, a disintegrin and metalloprotease. (B) Sperm from the epididymis and vas deferens were fractionated into heads and tails. These fractions were subjected to western blot analysis. ADAM2 localized on sperm head and α-tubulin composing the axoneme in the sperm flagellum were used as control proteins.