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Low density lipoprotein receptor-related protein mediates endocytic clearance of pro-MMP-2.TIMP-2 complex through a thrombospondin-independent mechanism.
- Source :
-
The Journal of biological chemistry [J Biol Chem] 2004 Dec 24; Vol. 279 (52), pp. 54944-51. Date of Electronic Publication: 2004 Oct 15. - Publication Year :
- 2004
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Abstract
- The low density lipoprotein receptor-related protein (LRP) mediates the endocytic clearance of various proteinases and proteinase.inhibitor complexes, including thrombospondin (TSP)-dependent endocytosis of matrix metalloproteinase (MMP)-2 (or gelatinase A), a key effector of extracellular matrix remodeling and cancer progression. However, the zymogen of MMP-2 (pro-MMP-2) mostly occurs in tissues as a complex with the tissue inhibitor of MMPs (TIMP-2). Here we show that clearance of the pro-MMP-2.TIMP-2 complex is also mediated by LRP, because addition of receptor-associated protein (RAP), a natural LRP ligand antagonist, inhibited endocytosis and lysosomal degradation of (125)I-pro-MMP-2.TIMP-2. Both TIMP-2 and the pro-MMP-2 collagen-binding domain independently competed for endocytosis of (125)I-pro-MMP-2.TIMP-2 complex. Surface plasmon resonance studies indicated that pro-MMP-2, TIMP-2, and pro-MMP-2.TIMP-2 directly interact with LRP in the absence of TSP. LRP-mediated endocytic clearance of (125)I-pro-MMP-2 was inhibited by anti-TSP antibodies and accelerated upon complexing with TSP-1, but these treatments had no effect on (125)I-pro-MMP-2.TIMP-2 uptake. This implies that mechanisms of clearance by LRP of pro-MMP-2 and pro-MMP-2.TIMP-2 complex are different. Interestingly, RAP did not inhibit binding of (125)I-pro-MMP-2.TIMP-2 to the cell surface. We conclude that clearance of pro-MMP-2.TIMP-2 complex is a TSP-independent two-step process, involving (i) initial binding to the cell membrane in a RAP-insensitive manner and (ii) subsequent LRP-dependent (RAP-sensitive) internalization and degradation.
- Subjects :
- Binding Sites
Cell Line
Cell Membrane metabolism
Collagen metabolism
Culture Media, Conditioned
Fibrosarcoma
Gene Expression
Humans
Matrix Metalloproteinase 2 genetics
Protein Precursors genetics
Protein Precursors metabolism
Recombinant Proteins
Thrombospondin 1 metabolism
Thrombospondin 1 pharmacology
Tissue Inhibitor of Metalloproteinase-2 genetics
Transfection
Tumor Cells, Cultured
Endocytosis physiology
Low Density Lipoprotein Receptor-Related Protein-1 physiology
Matrix Metalloproteinase 2 metabolism
Thrombospondins physiology
Tissue Inhibitor of Metalloproteinase-2 metabolism
Subjects
Details
- Language :
- English
- ISSN :
- 0021-9258
- Volume :
- 279
- Issue :
- 52
- Database :
- MEDLINE
- Journal :
- The Journal of biological chemistry
- Publication Type :
- Academic Journal
- Accession number :
- 15489233
- Full Text :
- https://doi.org/10.1074/jbc.M406792200