Novel transcription-factor-like function of human matrix metalloproteinase 3 regulating the CTGF/CCN2 gene

Mol Cell Biol. 2008 Apr;28(7):2391-413. doi: 10.1128/MCB.01288-07. Epub 2008 Jan 2.

Abstract

Matrix metalloproteinase 3 (MMP3) is well known as a secretory endopeptidase that degrades extracellular matrices. Recent reports indicated the presence of MMPs in the nucleus (A. J. Kwon et al., FASEB J. 18:690-692, 2004); however, its function has not been well investigated. Here, we report a novel function of human nuclear MMP3 as a trans regulator of connective tissue growth factor (CCN2/CTGF). Initially, we cloned MMP3 cDNA as a DNA-binding factor for the CCN2/CTGF gene. An interaction between MMP3 and transcription enhancer dominant in chondrocytes (TRENDIC) in the CCN2/CTGF promoter was confirmed by a gel shift assay and chromatin immunoprecipitation. The CCN2/CTGF promoter was activated by overexpressed MMP3, whereas a TRENDIC mutant promoter lost the response. Also, the knocking down of MMP3 suppressed CCN2/CTGF expression. By cytochemical and histochemical analyses, MMP3 was detected in the nuclei of chondrocytic cells in culture and also in the nuclei of normal and osteoarthritic chondrocytes in vivo. The nuclear translocation of externally added recombinant MMP3 and six putative nuclear localization signals in MMP3 also were shown. Furthermore, we determined that heterochromatin protein gamma coordinately regulates CCN2/CTGF by interacting with MMP3. The involvement of this novel role of MMP3 in the development, tissue remodeling, and pathology of arthritic diseases through CCN2/CTGF regulation thus is suggested.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Cell Line, Tumor / metabolism
  • Cell Nucleus / metabolism
  • Chondrocytes / metabolism*
  • Connective Tissue Growth Factor
  • Consensus Sequence
  • Enhancer Elements, Genetic / genetics*
  • Female
  • Gene Expression Regulation / genetics*
  • Humans
  • Immediate-Early Proteins / biosynthesis
  • Immediate-Early Proteins / genetics*
  • Intercellular Signaling Peptides and Proteins / biosynthesis
  • Intercellular Signaling Peptides and Proteins / genetics*
  • Matrix Metalloproteinase 3 / physiology*
  • Mice
  • Mice, Inbred BALB C
  • Molecular Sequence Data
  • Osteoarthritis / metabolism
  • Protease Inhibitors / pharmacology
  • Rats
  • Rats, Wistar
  • Recombinant Fusion Proteins / physiology
  • Sequence Alignment
  • Sequence Homology, Nucleic Acid

Substances

  • CCN2 protein, human
  • CCN2 protein, mouse
  • CCN2 protein, rat
  • Immediate-Early Proteins
  • Intercellular Signaling Peptides and Proteins
  • Protease Inhibitors
  • Recombinant Fusion Proteins
  • Connective Tissue Growth Factor
  • MMP3 protein, human
  • Matrix Metalloproteinase 3