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The comparative role of activator protein 1 and Smad factors in the regulation of Timp-1 and MMP-1 gene expression by transforming growth factor-beta 1.
- Source :
-
The Journal of biological chemistry [J Biol Chem] 2003 Mar 21; Vol. 278 (12), pp. 10304-13. Date of Electronic Publication: 2003 Jan 13. - Publication Year :
- 2003
-
Abstract
- The balance between matrix metalloproteinases (MMPs) and their inhibitors, the tissue inhibitors of metalloproteinases (TIMPs), is pivotal in the remodeling of extracellular matrix. TGF-beta has profound effects on extracellular matrix homeostasis, in part via its ability to alter this balance at the level of gene expression. The intracellular signaling pathways by which TGF-beta mediates its actions include the Smad pathway, specific to the TGF-beta superfamily, but also, for example, mitogen-activated protein kinase pathways; furthermore, cross-talk between the Smads and other signaling pathways modifies the TGF-beta response. The reciprocal effect of TGF-beta on the expression of Timp-1 and MMP-1 supports its role in matrix anabolism, yet the mechanisms by which TGF-beta induces Timp-1 and represses induced MMP-1 have remained opaque. Here, we (i) investigate the mechanism(s) by which TGF-beta1 induces expression of the Timp-1 gene and (ii) compare this with TGF-beta1 repression of phorbol ester-induced MMP-1 expression. We report that the promoter-proximal activator protein 1 (AP1) site is essential for the response of both Timp-1 and MMP-1 to TGF-beta (induction and repression, respectively). c-Fos, JunD, and c-Jun are essential for the induction of Timp-1 gene expression by TGF-beta1, but these AP1 factors transactivate equally well from both Timp-1 and MMP-1 AP1 sites. Smad-containing complexes do not interact with the Timp-1 AP1 site, and overexpression of Smads does not substitute or potentiate the induction of the gene by TGF-beta1; furthermore, Timp-1 is still induced by TGF-beta1 in Smad knockout cell lines, although to varying extents. In contrast, Smads do interact with the MMP-1 AP1 site and mediate repression of induced MMP-1 gene expression by TGF-beta1.
- Subjects :
- Animals
Cells, Cultured
Mice
Promoter Regions, Genetic
Protein Binding
Smad2 Protein
Smad3 Protein
Smad4 Protein
Tetradecanoylphorbol Acetate pharmacology
Transcriptional Activation
Transforming Growth Factor beta1
DNA-Binding Proteins physiology
Gene Expression Regulation
Matrix Metalloproteinase 1 genetics
Tissue Inhibitor of Metalloproteinase-1 genetics
Trans-Activators physiology
Transcription Factor AP-1 physiology
Transforming Growth Factor beta physiology
Subjects
Details
- Language :
- English
- ISSN :
- 0021-9258
- Volume :
- 278
- Issue :
- 12
- Database :
- MEDLINE
- Journal :
- The Journal of biological chemistry
- Publication Type :
- Academic Journal
- Accession number :
- 12525489
- Full Text :
- https://doi.org/10.1074/jbc.M212334200