Bromodomain protein 7 interacts with PRMT5 and PRC2, and is involved in transcriptional repression of their target genes

Nucleic Acids Res. 2011 Jul;39(13):5424-38. doi: 10.1093/nar/gkr170. Epub 2011 Mar 29.

Abstract

Histone modification regulates gene expression, and one major regulatory step in this process is the ability of proteins that recognize epigenetic marks to recruit enzymes required to specify transcriptional outcome. Here we show that BRD7 is a component of hSWI-SNF complexes that interacts with PRMT5 and PRC2. Recruitment studies revealed that BRD7 co-localizes with PRMT5 and PRC2 on 'suppressor of tumorigenecity 7' (ST7) and retinoblastoma-like protein 2 (RBL2) promoters in patient-derived B cell lines, and that its association with these target genes correlates with hypermethylation of H3R8, H4R3 and H3K27. Furthermore, inhibition of BRD7 expression reduces PRMT5 and PRC2 recruitment to ST7 and RBL2 promoters; however, only ST7 becomes transcriptionally derepressed. Evaluation of the PRMT5- and PRC2-induced epigenetic marks revealed that while H3(Me(2))R8, H4(Me(2))R3 and H3(Me(3))K27 marks are erased from the ST7 promoter, demethylation of RBL2 promoter histones is incomplete. We also show that the arginine demethylase (RDM) JMJD6, which can erase PRMT5-induced H4R3 methylation, and the H3K27-lysine-specific demethylases, KDM6A/UTX and KDM6B/JMJD3, are differentially recruited to ST7 and RBL2. These findings highlight the role played by BRD7 in PRMT5- and PRC2-induced transcriptional silencing, and indicate that recruitment of specific RDMs and KDMs is required for efficient transcriptional derepression.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adaptor Proteins, Signal Transducing / metabolism
  • Carrier Proteins / metabolism
  • Cell Line, Tumor
  • Chromatin Assembly and Disassembly
  • Chromosomal Proteins, Non-Histone / antagonists & inhibitors
  • Chromosomal Proteins, Non-Histone / metabolism*
  • Gene Silencing*
  • HeLa Cells
  • Histone Demethylases / metabolism
  • Humans
  • Leukemia / genetics
  • Lymphoma / genetics
  • Neoplasm Proteins
  • Nuclear Proteins / metabolism
  • Polycomb Repressive Complex 2
  • Polycomb-Group Proteins
  • Promoter Regions, Genetic
  • Protein Methyltransferases / metabolism*
  • Protein-Arginine N-Methyltransferases
  • Repressor Proteins / metabolism*
  • Retinoblastoma-Like Protein p130 / genetics
  • Transcription Factors
  • Transcription, Genetic
  • Tumor Suppressor Proteins / genetics

Substances

  • Adaptor Proteins, Signal Transducing
  • BRD7 protein, human
  • Carrier Proteins
  • Chromosomal Proteins, Non-Histone
  • MEP50 protein, human
  • Neoplasm Proteins
  • Nuclear Proteins
  • Polycomb-Group Proteins
  • RBL2 protein, human
  • Repressor Proteins
  • Retinoblastoma-Like Protein p130
  • ST7 protein, human
  • SUZ12 protein, human
  • Transcription Factors
  • Tumor Suppressor Proteins
  • Histone Demethylases
  • Protein Methyltransferases
  • PRMT5 protein, human
  • Protein-Arginine N-Methyltransferases
  • Polycomb Repressive Complex 2