Ectopically tethered CP190 induces large-scale chromatin decondensation

Sci Rep. 2014 Jan 29:4:3917. doi: 10.1038/srep03917.

Abstract

Insulator mediated alteration in higher-order chromatin and/or nucleosome organization is an important aspect of epigenetic gene regulation. Recent studies have suggested a key role for CP190 in such processes. In this study, we analysed the effects of ectopically tethered insulator factors on chromatin structure and found that CP190 induces large-scale decondensation when targeted to a condensed lacO array in mammalian and Drosophila cells. In contrast, dCTCF alone, is unable to cause such a decondensation, however, when CP190 is present, dCTCF recruits it to the lacO array and mediates chromatin unfolding. The CP190 induced opening of chromatin may not be correlated with transcriptional activation, as binding of CP190 does not enhance luciferase activity in reporter assays. We propose that CP190 may mediate histone modification and chromatin remodelling activity to induce an open chromatin state by its direct recruitment or targeting by a DNA binding factor such as dCTCF.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line
  • Cell Line, Tumor
  • Chromatin / genetics*
  • Chromatin / metabolism*
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism
  • Drosophila / genetics
  • Drosophila / metabolism
  • Drosophila Proteins / genetics*
  • Drosophila Proteins / metabolism*
  • HEK293 Cells
  • Humans
  • Insulator Elements / genetics*
  • Mammals / metabolism
  • Microtubule-Associated Proteins / genetics*
  • Microtubule-Associated Proteins / metabolism*
  • Nuclear Proteins / genetics*
  • Nuclear Proteins / metabolism*
  • Protein Binding / genetics
  • Transcriptional Activation / genetics
  • Transfection / methods

Substances

  • CP190 protein, Drosophila
  • Chromatin
  • DNA-Binding Proteins
  • Drosophila Proteins
  • Microtubule-Associated Proteins
  • Nuclear Proteins