MoY, a Y-linked sex-determining gene in Medfly
The article in Science reports the discovery of the Y-linked gene MoY in Medfly, a long-sought primary trigger for male development.
Image description: Mitotic metaphase of Medfly male (2n = 12) shows TSA-FISH mapping of the MoY gene to the long arm of the Y chromosome (green signals) performed by two members of our Laboratory of Molecular Cytogenetics, who participated in this research.
Ceratitis capitata (Mediterranean fruit fly, or Medfly) is a serious invasive fruit pest, like dozens of other fruit flies of the family Tephritidae. Besides pesticides, the most successful method to control Medfly is the sterile insect technique (SIT), which relies on the release of mass-reared and radiation-sterilized males that suppress wild populations by mating with wild females. The male-only releases require the use of a genetic sexing strain, which is currently only possible in Medfly. For many years, scientists have been looking for a sex-determining gene in Medfly that would allow the development of more effective sexing methods not only in Medfly but possibly also in other tephritid pests. However, rapidly evolving primary sex-determining signals vary widely in insects, so identifying them is a challenge. Recently, an international group of experts led by an Italian geneticist, Giuseppe Saccone, discovered a Y-linked gene, Maleness-on-the-Y (MoY), encoding a small protein. The publication in Science demonstrates that MoY is a long-sought sex-determining gene in Medfly because it is both necessary and sufficient to initiate male development during embryogenesis. In addition, MoY is Y-linked and functionally conserved in other species of the Tephritidae family, which is promising for developing more effective control strategies such as SIT against these major agricultural insect pests.
Meccariello A., Salvemini M., Primo P., Hall B., Koskinioti P., Dalíková M., Gravina A., Gucciardino M. A., Forlenza F., Gregoriou M. E., Ippolito D., Monti S. M., Petrella V., Perrotta M. M., Schmeing S., Ruggiero A., Scolari F., Giordano E., Tsoumani K. T., Marec F., Windbichler N., Arunkumar K. P., Bourtzis K., Mathiopoulos K. D., Ragoussis J., Vitagliano L., Tu Z., Papathanos P. A., Robinson M. D., Saccone G. (2019) Maleness-on-the-Y (MoY) orchestrates male sex determination in major agricultural fruit fly pests. Science 27: eaax1318.