C. elegans Rb, NuRD, and Ras regulate lin-39-mediated cell fusion during vulval fate specification

Curr Biol. 2001 Nov 27;11(23):1874-9. doi: 10.1016/s0960-9822(01)00596-6.


The tumor suppressor Rb and the NuRD (nucleosome remodeling and histone deacetylation) complex have been implicated in transcriptional repression during cell cycle progression and cell fate specification. The Rb/E2F complex physically interacts with and thus recruits the NuRD complex to actively repress transcription. Caenorhabditis elegans counterparts of Rb, E2F/DP, and some NuRD complex components appear to function in a common class B synthetic Multivulva (synMuv) pathway to antagonize RTK/Ras signaling during vulval fate specification. Therefore, it has been suggested that they function together in a single complex to repress vulva-specific gene transcription. However, little is known about the in vivo interactions between these class B synMuv genes and their relationships with other pathways in specific cellular processes during vulval development. We show that C. elegans Rb/E2F and NuRD complexes antagonize Ras activity by controlling a lin-39 Hox-mediated cell fusion event that regulates the competence of vulval cells. Interestingly, Rb/E2F and NuRD complexes exhibit very different genetic properties. While the NuRD complex negatively regulates lin-39 Hox activity, likely by downregulating its expression, RB/E2F appears to play dual roles in regulating lin-39: a negative role in controlling its activity and a previously uncharacterized positive role in regulating its expression.

Publication types

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

MeSH terms

  • Animals
  • Caenorhabditis elegans / cytology
  • Caenorhabditis elegans / genetics
  • Caenorhabditis elegans / growth & development
  • Caenorhabditis elegans / physiology*
  • Caenorhabditis elegans Proteins*
  • Cell Cycle Proteins*
  • Cell Fusion*
  • Cell Lineage
  • DNA-Binding Proteins*
  • E2F Transcription Factors
  • Female
  • Genes, Helminth
  • Histone Deacetylases / physiology*
  • Homeodomain Proteins / physiology*
  • Mi-2 Nucleosome Remodeling and Deacetylase Complex
  • Transcription Factors / physiology*
  • Vulva / cytology*
  • Vulva / growth & development
  • ras Proteins / physiology*


  • Caenorhabditis elegans Proteins
  • Cell Cycle Proteins
  • DNA-Binding Proteins
  • E2F Transcription Factors
  • Homeodomain Proteins
  • Transcription Factors
  • efl-1 protein, C elegans
  • lin-39 protein, C elegans
  • Histone Deacetylases
  • Mi-2 Nucleosome Remodeling and Deacetylase Complex
  • ras Proteins