Variant PRC1 complex-dependent H2A ubiquitylation drives PRC2 recruitment and polycomb domain formation

Cell. 2014 Jun 5;157(6):1445-1459. doi: 10.1016/j.cell.2014.05.004. Epub 2014 May 22.

Abstract

Chromatin modifying activities inherent to polycomb repressive complexes PRC1 and PRC2 play an essential role in gene regulation, cellular differentiation, and development. However, the mechanisms by which these complexes recognize their target sites and function together to form repressive chromatin domains remain poorly understood. Recruitment of PRC1 to target sites has been proposed to occur through a hierarchical process, dependent on prior nucleation of PRC2 and placement of H3K27me3. Here, using a de novo targeting assay in mouse embryonic stem cells we unexpectedly discover that PRC1-dependent H2AK119ub1 leads to recruitment of PRC2 and H3K27me3 to effectively initiate a polycomb domain. This activity is restricted to variant PRC1 complexes, and genetic ablation experiments reveal that targeting of the variant PCGF1/PRC1 complex by KDM2B to CpG islands is required for normal polycomb domain formation and mouse development. These observations provide a surprising PRC1-dependent logic for PRC2 occupancy at target sites in vivo.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bone Development
  • CpG Islands
  • Embryonic Stem Cells / metabolism*
  • F-Box Proteins / chemistry
  • F-Box Proteins / genetics
  • F-Box Proteins / metabolism*
  • Genes, Lethal
  • Genome-Wide Association Study
  • Histones / metabolism*
  • Jumonji Domain-Containing Histone Demethylases / chemistry
  • Jumonji Domain-Containing Histone Demethylases / genetics
  • Jumonji Domain-Containing Histone Demethylases / metabolism*
  • Mice
  • Polycomb Repressive Complex 1 / metabolism*
  • Polycomb Repressive Complex 2 / metabolism*
  • Protein Structure, Tertiary

Substances

  • F-Box Proteins
  • Histones
  • Jumonji Domain-Containing Histone Demethylases
  • Kdm2b protein, mouse
  • Polycomb Repressive Complex 2
  • Polycomb Repressive Complex 1

Associated data

  • GEO/GSE55698