Dicer-dependent turnover of intergenic transcripts from the human beta-globin gene cluster

Mol Cell Biol. 2005 Nov;25(21):9724-33. doi: 10.1128/MCB.25.21.9724-9733.2005.

Abstract

The widespread occurrence of intergenic transcription in eukaryotes is increasingly evident. Intergenic transcription in the beta-globin gene cluster has been described in murine and human cells, and models for a role in gene and chromatin activation have been proposed. In this study, we analyze intergenic transcription and the chromatin state throughout the human beta-globin gene cluster and find that the data are not consistent with such activation-linked models. Thus, intergenic transcript levels correlate with neither chromatin activation nor globin gene expression. Instead, we find that intergenic transcripts of the beta-globin gene cluster are specifically upregulated in Dicer-deficient cells. This is accompanied by a shift towards more activated chromatin as indicated by changes in histone tail modifications. Our results strongly implicate RNA interference (RNAi)-related mechanisms in regulating intergenic transcription in the human beta-globin gene cluster and further suggest that RNAi-dependent chromatin silencing in vertebrates is not restricted to the centromeres.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Centromere / genetics
  • Chromatin / genetics
  • Chromatin / physiology
  • DNA, Intergenic / genetics*
  • Globins / genetics*
  • HeLa Cells
  • Histones / genetics
  • Humans
  • Multigene Family
  • RNA Interference
  • Ribonuclease III / genetics*
  • Ribonuclease III / physiology
  • Transcription, Genetic*

Substances

  • Chromatin
  • DNA, Intergenic
  • Histones
  • Globins
  • Ribonuclease III