Purified transcription factor AP-1 interacts with TPA-inducible enhancer elements

Cell. 1987 Jun 19;49(6):741-52. doi: 10.1016/0092-8674(87)90612-x.

Abstract

The enhancer-binding protein AP-1 has been purified to greater than 95% homogeneity from HeLa cells by sequence-specific DNA affinity chromatography and identified as a 47 kd polypeptide. Purified AP-1 activates transcription in vitro of the wild-type human metallothionein IIA (hMT IIA) gene but not mutant hMT IIA promoters lacking AP-1 recognition sites. DNAase I protection analysis indicates that genetically defined enhancer elements in hMT IIA, SV40, and the human collagenase gene contain high-affinity AP-1-binding sites, each with a conserved recognition motif, TGACTCA. These three genes are transcriptionally induced by treatment of cells with the tumor promoter TPA. Here we demonstrate that multiple synthetic copies of the consensus AP-1-binding site can act as TPA-inducible enhancers in various plasmid constructs after transfection into HeLa cells. These findings suggest that AP-1 is a transcription factor that functions by interacting with a specific enhancer element, and that its activities may be modulated by treatment of cells with TPA, known to stimulate protein kinase C.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Base Sequence
  • Binding Sites
  • DNA-Binding Proteins / genetics*
  • DNA-Binding Proteins / isolation & purification
  • Enhancer Elements, Genetic*
  • Gene Expression Regulation
  • Genes, Regulator*
  • Humans
  • Metallothionein / genetics*
  • Microbial Collagenase / genetics*
  • Molecular Weight
  • Mutation
  • Proto-Oncogene Proteins c-jun
  • Simian virus 40 / genetics*
  • Tetradecanoylphorbol Acetate / pharmacology*
  • Transcription Factors / genetics*
  • Transcription Factors / isolation & purification

Substances

  • DNA-Binding Proteins
  • Proto-Oncogene Proteins c-jun
  • Transcription Factors
  • Metallothionein
  • Microbial Collagenase
  • Tetradecanoylphorbol Acetate