E2-mediated cathepsin D (CTSD) activation involves looping of distal enhancer elements

Mol Oncol. 2008 Aug;2(2):182-90. doi: 10.1016/j.molonc.2008.05.004. Epub 2008 May 29.

Abstract

Estrogen receptor alpha (ERalpha) is a ligand dependent transcription factor that regulates the expression of target genes through interacting with cis-acting estrogen response elements (EREs). However, only a minority of ERalpha binding sites are located within the proximal promoter regions of responsive genes. Here we report the characterization of an ERE located 9kbp upstream of the TSS of the cathepsin D gene (CTSD) that up-regulates CTSD expression upon estrogen stimulation in MCF-7 cells. Using ChIP, we show recruitment of ERalpha and phosphorylated PolII at the CTSD distal enhancer region. Moreover, we determine the kinetics of transient CpG methylation on the promoter region of CTSD and for the first time, at a distal enhancer element. We show that ERalpha is crucial for long-distance regulation of CTSD expression involving a looping mechanism.

MeSH terms

  • Binding Sites
  • Cathepsin D / genetics*
  • Cell Line, Tumor
  • DNA Methylation
  • DNA Polymerase III / metabolism
  • Enhancer Elements, Genetic*
  • Estradiol / pharmacology
  • Estrogen Receptor alpha / physiology*
  • Humans
  • Promoter Regions, Genetic
  • Transcriptional Activation*

Substances

  • ESR1 protein, human
  • Estrogen Receptor alpha
  • Estradiol
  • DNA Polymerase III
  • Cathepsin D