Maleness-on-the-Y (MoY) orchestrates male sex determination in major agricultural fruit fly pests

Abstract

Making males in a fruit fly pest The Mediterranean fruit fly or Medfly (Ceratitis capitata) is a global and highly destructive fruit pest. Meccariello et al. identified the master gene for male sex determination on the Y chromosome of Medfly and named it Maleness-on-the-Y (MoY) (see the Perspective by Makki and Meller). Flies of each sex were transformed into the other sex by genetic manipulation, and crosses of transformed files generated male and female progeny. MoY is functionally conserved in the olive fruit fly and in the invasive oriental fruit fly. This discovery has potential for insect genetic control based on mass release of sterile males and future strategies based on gene drive. Science, this issue p. 1457; see also p. 1380 The Medfly male-determining factor is a Y-linked gene encoding a small protein that is conserved in major fruit fly pests. In insects, rapidly evolving primary sex-determining signals are transduced by a conserved regulatory module controlling sexual differentiation. In the agricultural pest Ceratitis capitata (Mediterranean fruit fly, or Medfly), we identified a Y-linked gene, Maleness-on-the-Y (MoY), encoding a small protein that is necessary and sufficient for male development. Silencing or disruption of MoY in XY embryos causes feminization, whereas overexpression of MoY in XX embryos induces masculinization. Crosses between transformed XY females and XX males give rise to males and females, indicating that a Y chromosome can be transmitted by XY females. MoY is Y-linked and functionally conserved in other species of the Tephritidae family, highlighting its potential to serve as a tool for developing more effective control strategies against these major agricultural insect pests.