Disruption of an SP2/KLF6 repression complex by SHP is required for farnesoid X receptor-induced endothelial cell migration

J Biol Chem. 2006 Dec 22;281(51):39105-13. doi: 10.1074/jbc.M607720200. Epub 2006 Oct 27.

Abstract

The farnesoid X receptor (FXR) signaling pathway regulates bile acid and cholesterol homeostasis. Here, we demonstrate, using a variety of gain- and loss-of-function approaches, a role of FXR in the process of cell motility, which involves the small heterodimeric partner (SHP)-dependent up-regulation of matrix metalloproteinase-9. We use this observation to reveal a transcriptional regulatory mechanism involving the SP/KLF transcription factors, SP2 and KLF6. Small interference RNA-based silencing studies in combination with promoter, gel shift, and chromatin immunoprecipitation assays indicate that SP2 and KLF6 bind to the matrix metalloproteinase-9 promoter and together function to maintain this gene in a silenced state. However, upon activation of FXR, SHP interacts with SP2 and KLF6, disrupting the SP2/KLF6 repressor complex. Thus, together, these studies identify a mechanism for antagonizing Sp/KLF protein repression function via SHP, with this process regulating endothelial cell motility.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Movement
  • DNA-Binding Proteins / chemistry*
  • Endothelial Cells / metabolism*
  • Gene Expression Regulation
  • Gene Silencing
  • Humans
  • Kruppel-Like Factor 6
  • Kruppel-Like Transcription Factors / metabolism
  • Kruppel-Like Transcription Factors / physiology*
  • Matrix Metalloproteinase 9 / metabolism*
  • Models, Biological
  • Oligonucleotide Array Sequence Analysis
  • Proto-Oncogene Proteins / metabolism
  • Proto-Oncogene Proteins / physiology*
  • RNA, Small Interfering / metabolism
  • Receptors, Cytoplasmic and Nuclear / chemistry*
  • Signal Transduction
  • Sp1 Transcription Factor / metabolism
  • Transcription Factors / chemistry*
  • Transcription, Genetic

Substances

  • DNA-Binding Proteins
  • KLF6 protein, human
  • Kruppel-Like Factor 6
  • Kruppel-Like Transcription Factors
  • Proto-Oncogene Proteins
  • RNA, Small Interfering
  • Receptors, Cytoplasmic and Nuclear
  • Sp1 Transcription Factor
  • Transcription Factors
  • farnesoid X-activated receptor
  • Matrix Metalloproteinase 9