<i>Maleness-on-the-Y</i> (<i>MoY</i>) orchestrates male sex determination in major agricultural fruit fly pests.

Abstract

In insects, rapidly evolving primary sex-determining signals are transduced by a conserved regulatory module controlling sexual differentiation. In the agricultural pest <i>Ceratitis capitata</i> (Mediterranean fruit fly, or Medfly), we identified a Y-linked gene, <i>Maleness-on-the-Y</i> (<i>MoY</i>), encoding a small protein that is necessary and sufficient for male development. Silencing or disruption of <i>MoY</i> in XY embryos causes feminization, whereas overexpression of <i>MoY</i> 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. <i>MoY</i> 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.