A POP-1 repressor complex restricts inappropriate cell type-specific gene transcription during Caenorhabditis elegans embryogenesis

EMBO J. 2001 Dec 17;20(24):7197-208. doi: 10.1093/emboj/20.24.7197.

Abstract

In Caenorhabditis elegans, histone acetyltransferase CBP-1 counteracts the repressive activity of the histone deacetylase HDA-1 to allow endoderm differentiation, which is specified by the E cell. In the sister MS cell, the endoderm fate is prevented by the action of an HMG box-containing protein, POP-1, through an unknown mechanism. In this study, we show that CBP-1, HDA-1 and POP-1 converge on end-1, an initial endoderm-determining gene. In the E lineage, an essential function of CBP-1 appears to be the activation of end-1 transcription. We further identify a molecular mechanism for the endoderm-suppressive effect of POP-1 in the MS lineage by demonstrating that POP-1 functions as a transcriptional repressor that inhibits inappropriate end-1 transcription. We provide evidence that POP-1 represses transcription via the recruitment of HDA-1 and UNC-37, the C.elegans homolog of the co-repressor Groucho. These findings demonstrate the importance of the interplay between acetyltransferases and deacetylases in the regulation of a critical cell fate-determining gene during development. Furthermore, they identify a strategy by which concerted actions of histone deacetylases and other co-repressors ensure maximal repression of inappropriate cell type-specific gene transcription.

Publication types

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

MeSH terms

  • Animals
  • Caenorhabditis elegans / embryology*
  • Caenorhabditis elegans / genetics
  • Caenorhabditis elegans Proteins*
  • DNA-Binding Proteins / physiology*
  • GATA Transcription Factors
  • Helminth Proteins / physiology*
  • High Mobility Group Proteins / physiology*
  • Promoter Regions, Genetic
  • Repressor Proteins / physiology*
  • Transcription Factors / genetics
  • Transcription Factors / physiology
  • Transcription, Genetic / physiology*

Substances

  • Caenorhabditis elegans Proteins
  • DNA-Binding Proteins
  • END-1 protein, C elegans
  • GATA Transcription Factors
  • Helminth Proteins
  • High Mobility Group Proteins
  • Repressor Proteins
  • Transcription Factors
  • pop-1 protein, C elegans
  • unc-37 protein, C elegans