Xenopus cytoskeletal actin and human c-fos gene promoters share a conserved protein-binding site

EMBO J. 1987 Mar;6(3):667-73.


Xenopus laevis cytoskeletal actin gene promoters contain a 20-bp sequence homologous to the serum response element (SRE) required for transient human c-fos gene transcription in response to serum factors. Both sequences bind the same factor in HeLa cell extracts, as shown by binding competition, DNase I and dimethylsulphate (DMS) protection and DMS interference assays. A similar protein is present in Xenopus laevis oocytes. Sequences containing the SRE homology are essential for constitutive activity of the actin promoter in both Xenopus and mouse cells, and a synthetic SRE functions as a promoter element in these cells. In mouse cells, transcription of both transfected Xenopus actin and actin/c-fos fusion genes is activated following serum stimulation. These data suggest that the SRE and its cognate protein form part of a regulatory pathway that has been highly conserved during evolution.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actins / genetics*
  • Animals
  • Base Sequence
  • Genes*
  • HeLa Cells / metabolism
  • Humans
  • Mice
  • Promoter Regions, Genetic*
  • Protein Binding
  • Proto-Oncogenes*
  • Sequence Homology, Nucleic Acid
  • Xenopus laevis


  • Actins