Specificity of nuclear protein binding to a CYP1A1 negative regulatory element

Scott R. Nagy, Michael S. Denison

Research output: Contribution to journalArticle

4 Scopus citations

Abstract

Primary cultures of rat epidermal keratinocytes lose the ability to respond to chemicals with the induction of CYP1A1 gene expression after approximately 15 passages. This repression is mediated by a CT-rich direct repeat negative regulatory DNA (NeRD) element present in the upstream regulatory region of the CYP1A1 gene. Competitive gel retardation analysis using keratinocyte nuclear extracts and mutant NeRD oligonucleotides revealed the presence of two specific protein-NeRD complexes and revealed the specific nucleotides important for the formation of each complex. These studies demonstrate that these two factors bind to overlapping sites within the NeRD element. Nucleotide specificity of complex A formation is similar to that of previously identified nuclear silencing factors, while that of complex B appears to represent a unique CT-rich binding factor. These results suggest that repression of CYP1A1 gene expression in high passage keratinocytes may involve the interplay between at least two specific NeRD binding factors.

Original languageEnglish (US)
Pages (from-to)799-805
Number of pages7
JournalBiochemical and Biophysical Research Communications
Volume296
Issue number4
DOIs
StatePublished - 2002

    Fingerprint

Keywords

  • 2,3,7,8-Tetrachlorodibenzo-p-dioxin
  • Ah receptor
  • CYP1A1
  • Gene silencing
  • Keratinocyte
  • TCDD

ASJC Scopus subject areas

  • Biochemistry
  • Biophysics
  • Molecular Biology

Cite this