Intronic regulation of matrix metalloproteinase-2 revealed by in vivo transcriptional analysis in ischemia

Proc Natl Acad Sci U S A. 2005 Nov 8;102(45):16345-50. doi: 10.1073/pnas.0508085102. Epub 2005 Oct 28.

Abstract

Matrix metalloproteinase-2 (MMP-2) plays an essential role in angiogenesis and arteriogenesis, two processes critical to restoration of tissue perfusion after ischemia. MMP-2 expression is increased in tissue ischemia, but the responsible mechanisms remain unknown. We studied the transcriptional activation of the MMP-2 gene in a model of hindlimb ischemia by using various MMP-2-lacZ reporter mice and chromatin immunoprecipitation. MMP-2 activity and mRNA were increased after hindlimb ischemia. Mice with targeted deletion of MMP-2 had impaired restoration of perfusion and a high incidence of limb gangrene, indicating that MMP-2 plays a critical role in ischemia-induced revascularization. Ischemia induced the expression and binding of c-Fos, c-Jun, JunB, FosB, and Fra2 to a noncanonical activating protein-1 (AP-1) site present in the MMP-2 promoter and decreased binding of the transcriptional repressor JunD. Ischemia also activated the expression and binding of p53 to an adjacent enhancer site (RE-1) and increased expression and binding of nuclear factor of activated T-cells-c2 to consensus sequences within the first intron. Deletion of either the 5' AP-1/RE-1 region of the promoter or substitution of the first intron abolished ischemia-induced MMP-2 transcription in vivo. Thus, AP-1 transcription factors and intronic activation by nuclear factor of activated T-cells-c2 act in concert to drive ischemia-induced MMP-2 transcription. These findings define a critical role for MMP-2 in ischemia-induced revascularization and identify both previously uncharacterized regulatory elements within the MMP-2 gene and the cognate transcription factors required for MMP-2 activation in vivo after tissue ischemia.

Publication types

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

MeSH terms

  • Animals
  • Enhancer Elements, Genetic
  • Hindlimb / blood supply
  • Introns*
  • Ischemia / enzymology*
  • Matrix Metalloproteinase 2 / genetics*
  • Mice
  • Mice, Inbred C57BL
  • Muscle, Skeletal / enzymology
  • NFATC Transcription Factors / metabolism
  • Promoter Regions, Genetic
  • Transcription Factor AP-1 / metabolism
  • Transcription, Genetic*
  • Tumor Suppressor Protein p53 / metabolism

Substances

  • NFATC Transcription Factors
  • Nfatc2 protein, mouse
  • Transcription Factor AP-1
  • Tumor Suppressor Protein p53
  • Matrix Metalloproteinase 2