40. Lessons from the Fruit Fly
Mariana Wolfner
Mariana F. Wolfner, Molecular Biology and Genetics, and a research colleague found that seminal fluid can impact the female fruit fly’s fertility—a discovery that offers clues to human reproduction. The researchers identified six accessory-gland proteins in the seminal fluid of fruit flies that affect reproduction by changing the female’s post-mating behavior and physiology. They found that one of the proteins is required to stimulate egg production fully in the Drosophila female on the first day after mating. The other five proteins sustain changes in the female caused by mating, such as increasing her egg production and reducing her likelihood to mate again. Until now, the ability in insects to maintain these responses had been associated with a single insect-specific accessory-gland protein. Maintaining these responses after mating requires the presence of stored sperm. Females of all internally mating species store sperm in the body, from a few days in most mammals to 20 years in some bees and ants. Studying Drosophila gives researchers a workable model for pinpointing the functions of such proteins. These insights may direct future studies on the function of these classes of seminal proteins in humans, which may advance understanding of some cases of infertility in humans. The research may also aid in developing new strategies to control insects that transmit human diseases. The mosquitoes that transmit dengue fever and West Nile Virus, for example, are “cousins” of fruit flies.