Germ granules in Drosophila

Traffic. 2019 Sep;20(9):650-660. doi: 10.1111/tra.12674. Epub 2019 Jul 31.


Germ granules are hallmarks of all germ cells. Early ultrastructural studies in Drosophila first described these membraneless granules in the oocyte and early embryo as filled with amorphous to fibrillar material mixed with RNA. Genetic studies identified key protein components and specific mRNAs that regulate germ cell-specific functions. More recently these ultrastructural studies have been complemented by biophysical analysis describing germ granules as phase-transitioned condensates. In this review, we provide an overview that connects the composition of germ granules with their function in controlling germ cell specification, formation and migration, and illuminate these mysterious condensates as the gatekeepers of the next generation.

Keywords: Oskar; RNA granules; RNA localization; germ granules; localized translation; mRNA clusters; phase separation; vasa, nanos.

Publication types

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

MeSH terms

  • Animals
  • Cytoplasmic Granules / metabolism*
  • Cytoplasmic Granules / ultrastructure
  • Drosophila Proteins / genetics
  • Drosophila Proteins / metabolism
  • Drosophila melanogaster / cytology
  • Drosophila melanogaster / genetics
  • Drosophila melanogaster / metabolism*
  • Gametogenesis
  • Germ Cells / cytology
  • Germ Cells / metabolism*
  • RNA / genetics
  • RNA / metabolism


  • Drosophila Proteins
  • RNA