Germ cells are required to maintain a stable sexual phenotype in adult zebrafish

Dev Biol. 2013 Apr 1;376(1):43-50. doi: 10.1016/j.ydbio.2013.01.016. Epub 2013 Jan 21.


Sex in zebrafish is not determined by a major chromosomal locus, but instead relies on a mechanism that is influenced by a germ cell-derived signal, as animals that lack germ cells, or specifically oocytes, develop as phenotypic males. These data suggest that during primary sex determination, an oocyte-derived signal acts on the bipotential somatic gonad to promote the female-specific program. However, it is not known if germ cells are required only during the primary sex-determining window, or if they are required throughout adult life to maintain the female sexual phenotype. Here, we show that while wild-type zebrafish do not switch sex as adults, germ cell-depleted adult females readily convert to a male phenotype. Notably, when oocytes are depleted, but germline stem cells remain, adult females sex-revert to sperm-producing males, indicating that a germ cell-derived signal acts on the somatic gonad to promote female development directly or indirectly by repressing male-specific gene expression. These results also confirm that signals from the somatic gonad in turn ensure that the sex appropriate gamete is produced.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Base Sequence
  • Cloning, Molecular
  • Female
  • Gene Expression Regulation / physiology*
  • Germ Cells / cytology
  • Germ Cells / metabolism*
  • Histological Techniques
  • Immunohistochemistry
  • In Situ Hybridization
  • Male
  • Metronidazole
  • Models, Biological
  • Molecular Sequence Data
  • Phenotype*
  • Plasmids / genetics
  • Sex Determination Processes / physiology*
  • Signal Transduction / physiology*
  • Stem Cells / cytology
  • Stem Cells / metabolism*
  • Zebrafish / embryology*


  • Metronidazole