Inhibition of rabbit collagenase (matrix metalloproteinase-1; MMP-1) transcription by retinoid receptors: evidence for binding of RARs/RXRs to the -77 AP-1 site through interactions with c-Jun

J Cell Physiol. 1996 Nov;169(2):320-32. doi: 10.1002/(SICI)1097-4652(199611)169:2<320::AID-JCP11>3.0.CO;2-D.

Abstract

Treatment of synovial fibroblasts with retinoic acid (RA) decreases their expression of collagenase (matrix metalloproteinase-1 or MMP-1), an enzyme that degrades interstitial collagens and contributes to the pathology of rheumatoid arthritis. This inhibition results, at least in part, from RA-induced decreases in the mRNA for the transactivators Fos and Jun (with concominant increases in RAR mRNA) and by sequestration of Fos/Jun by RARs/RXRs. Previously, we provided evidence that retinoid receptors are also present in complexes that bind to fragments of rabbit MMP-1 promoter DNA containing an AP-1 site at -77 (Pan et al., 1995, J. Cell. Biochem., 57:575-589). However, it was unclear whether RARs and retinoid X receptors (RXRs) were binding directly to the DNA or indirectly through another protein. We now use a sensitive MMP-1 promoter/luciferase reporter construct to confirm the transcriptional role of the AP-1 site at -77. In addition, with electrophoretic mobility shift analyses (EMSAs), antibody "supershifts" and DNAase 1 footprinting, we examine the interaction of retinoid receptors and AP-1 protein on the MMP-1 promoter. We demonstrate that RARs, RXRs, and c-Jun form a complex at the AP-1 site in which c-Jun binds directly to the DNA and apparently tethers the retinoid receptors to the complex. We conclude that retinoid receptors/AP-1 protein interactions at the DNA may provide an additional means of controlling collagenase gene transcription by retinoids.

Publication types

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

MeSH terms

  • Animals
  • Blotting, Western
  • Cells, Cultured
  • Collagenases / genetics
  • Collagenases / metabolism*
  • DNA Footprinting
  • DNA Probes / chemistry
  • Electrophoresis, Polyacrylamide Gel
  • Gene Expression Regulation / genetics
  • Genes, Reporter / genetics
  • Genetic Vectors
  • Matrix Metalloproteinase 1
  • Matrix Metalloproteinase Inhibitors
  • Nuclear Proteins / metabolism
  • Nuclear Proteins / pharmacology
  • Promoter Regions, Genetic / genetics
  • Proto-Oncogene Proteins c-jun / metabolism
  • Proto-Oncogene Proteins c-jun / pharmacology
  • Rabbits
  • Receptors, Retinoic Acid / metabolism*
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • Synovial Fluid / metabolism
  • Tetradecanoylphorbol Acetate / pharmacology
  • Transcription, Genetic / drug effects*
  • Transfection / genetics
  • Tretinoin / pharmacology

Substances

  • DNA Probes
  • Matrix Metalloproteinase Inhibitors
  • Nuclear Proteins
  • Proto-Oncogene Proteins c-jun
  • Receptors, Retinoic Acid
  • Recombinant Proteins
  • Tretinoin
  • Collagenases
  • Matrix Metalloproteinase 1
  • Tetradecanoylphorbol Acetate