A DROSOPHILA MALE ACCESSORY-GLAND PROTEIN THAT IS A MEMBER OF THE SERPIN SUPERFAMILY OF PROTEINASE-INHIBITORS IS TRANSFERRED TO FEMALES DURING MATING

Accessory gland peptide 76A, (Acp76A), belongs to the serpin superfami ly of proteins (serine protease inhibitors). Acp76A is a secreted prot ein synthesized only in the Drosophila melanogaster adult male accesso ry gland. Accumulation of the protein in males is first detected with polyclonal antibodies at 1 day after eclosion. The level of the protei n in virgin males reaches a peak 5-8 days post-eclosion, and remains c onstant for at least 20 days. Upon mating the amount of Acp76A in male s drops dramatically, but recovers by 24 h after mating. Immediately a fter mating the Acp76A is found in the female uterus. By 6 h after mat ing the amount of Acp76A detected in females is drastically reduced.