In vivo interaction proteomics in Caenorhabditis elegans embryos provides new insights into P granule dynamics


  • J.X. Chen
  • P.G. Cipriani
  • D. Mecenas
  • J. Polanowska
  • F. Piano
  • K.C. Gunsalus
  • M. Selbach


  • Molecular & Cellular Proteomics


  • Mol Cell Proteomics 15 (5): 1642-1657


  • Studying protein interactions in whole organisms is fundamental to understanding development. Here, we combine in vivo expressed GFP-tagged proteins with quantitative proteomics to identify protein-protein interactions of selected key proteins involved in early C. elegans embryogenesis. Co-affinity purification of interaction partners for eight bait proteins resulted in a pilot in vivo interaction map of proteins with a focus on early development. Our network reflects known biology and is highly enriched in functionally relevant interactions. To demonstrate the utility of the map, we looked for new regulators of P granule dynamics and found that GEI-12, a novel binding partner of the DYRK family kinase MBK-2, is a key regulator of P granule formation and germline maintenance. Our data corroborate a recently proposed model in which the phosphorylation state of GEI-12 controls P granule dynamics. In addition, we find that GEI-12 also induces granule formation in mammalian cells, suggesting a common regulatory mechanism in worms and humans. Our results show that in vivo interaction proteomics provides unique insights into animal development.