Wnt Signaling in Sexual Dimorphism

Genetics. 2016 Feb;202(2):661-73. doi: 10.1534/genetics.115.177857. Epub 2015 Nov 27.


The embryonic gonad of Drosophila melanogaster begins to display sexually dimorphic traits soon after its formation. Here we demonstrate the involvement of a wnt family ligand, wnt-2, in the induction of these sex-specific differences. We show that wnt-2 contributes to the survival of a male-specific population of somatic gonadal precursor cells (SGPs), the male-specific SGPs that are located at the posterior of the male gonad. We also show that the Wnt-2 ligand synergizes with the JAK-STAT ligand Upd, which is produced by SGPs at the anterior of the gonad to activate the STAT pathway in male germ cells. We suggest that the use of two spatially separated signaling systems to initiate the JAK-STAT stem cell maintenance pathway in germ cells provides a mechanism for increasing the pool of potential progenitors of the germline stem cells in the adult testes. Finally, we present evidence indicating that, like the JAK-STAT pathway, wnt-2 stimulates germ cells in male embryos to re-enter the cell cycle.

Keywords: Drosophila sex determination; Wnt pathway; nonautonomous signaling; sexual dimorphism.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Differentiation
  • Cell Division
  • Cell Survival
  • Drosophila melanogaster / embryology
  • Drosophila melanogaster / metabolism*
  • Embryo, Nonmammalian
  • Female
  • Gene Expression
  • Germ Cells / cytology
  • Germ Cells / metabolism
  • Gonads / cytology
  • Gonads / metabolism
  • Male
  • Mutation
  • STAT Transcription Factors / genetics
  • STAT Transcription Factors / metabolism
  • Sex Characteristics*
  • Testis / cytology
  • Testis / metabolism
  • Wnt Signaling Pathway*


  • STAT Transcription Factors