Biochemical characterization of the zinc-finger protein 217 transcriptional repressor complex: identification of a ZNF217 consensus recognition sequence

Oncogene. 2007 May 17;26(23):3378-86. doi: 10.1038/sj.onc.1210126. Epub 2006 Nov 27.

Abstract

Zinc-finger protein 217 (ZNF217) is a Kruppel-like zinc-finger protein located at 20q13.2, within a region of recurrent maximal amplification. Here, we demonstrate that ZNF217 is a transcriptional repressor protein and report the purification and characterization of a ZNF217 complex. The purified ZNF217 complex consists of approximately six proteins and contains the transcriptional co-repressors CoREST, BHC110/LSD1, histone deacetylase (HDAC) 2 and C-terminal binding protein (CtBP1). The purified ZNF217 complex possesses deacetylase activity as well as lysine 4 histone H3-specific demethylase activity that is most likely mediated by the BHC110/LSD1 component. To determine if ZNF217 is a sequence-specific binding protein, we have made use of cyclic amplification and selection of targets (CAST) assay and identify for the first time a ZNF217 DNA consensus recognition sequence (CRS) that is highly conserved in the human E-cadherin promoter. Chromatin immunoprecipitation (ChIP) experiments demonstrate that ZNF217, as well as the other components of the ZNF217 complex, are found on the region of the proximal E-cadherin promoter that contains the identified ZNF217 CRS in vivo. Using a combination of transient transfections and small interfering RNA, we demonstrate that ZNF217 represses the E-cadherin promoter. Collectively, our results implicate ZNF217 and its associated proteins in a novel pathway that may have profound effects on cancer progression.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • Binding Sites
  • Cadherins / genetics
  • Cadherins / metabolism
  • Cell Line, Tumor
  • Consensus Sequence
  • DNA / metabolism
  • DNA-Binding Proteins / metabolism
  • Down-Regulation*
  • Humans
  • Molecular Sequence Data
  • Promoter Regions, Genetic / genetics
  • Protein Binding
  • Sequence Alignment
  • Trans-Activators / genetics
  • Trans-Activators / isolation & purification
  • Trans-Activators / metabolism*
  • Transcription, Genetic / genetics

Substances

  • Cadherins
  • DNA-Binding Proteins
  • Trans-Activators
  • ZNF217 protein, human
  • DNA