Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.24.17 (MMP-3)
 3,419 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Multiple forms of metalloproteinase inhibitors were found in the serum-free conditioned medium of the EJ-1 human bladder carcinoma cell line by reverse zymography assay with gelatinase A as the indicator enzyme. Two novel forms of inhibitor with apparent molecular masses of 18 and 22 kDa on nonreducing SDS-polyacrylamide gel electrophoresis (PAGE), together with tissue inhibitor of metalloproteinases (TIMP) and TIMP-2, were purified from the conditioned medium by a series of chromatographic steps. Structural analysis showed that the 18-kDa inhibitor is a two-chain form of TIMP-2 (tc-TIMP-2) produced by proteolytic processing, and the 22-kDa inhibitor may be a partially glycosylated form of TIMP. The purified tc-TIMP-2 was separated into a 17-kDa peptide and a small peptide of about 2.5 kDa by reducing SDS-PAGE and into four isoforms with pI 7.6, 7.3, 7.2, and 6.8 by isoelectric focusing. tc-TIMP-2 has essentially the same inhibitory activity as TIMP-2 toward gelatinase A, collagenase, stromelysin, and matrilysin. Unlike TIMP-2, however, tc-TIMP-2 does not bind to the latent precursor fo gelatinase A. Similar two-chain forms of TIMP-2 were produced by its partial digestion with trypsin or less effectively with plasmin. These results suggest that proteolytic processing of TIMP-2 plays a role in the regulation of gelatinase A activity in the extracellular matrix.
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PMID:Purification and characterization of a two-chain form of tissue inhibitor of metalloproteinases (TIMP) type 2 and a low molecular weight TIMP-like protein. 831 98

The stromelysin-2 (SL-2) gene is transcriptionally active in normal human keratinocytes and encodes a secreted, catalytically competent but latent matrix metalloproteinase. Phorbolester induction resulted in the emergence of SL-2 (but not SL-1 transcripts), whereas the opposite was true for human mucosal fibroblasts. Expression of keratinocyte SL-2 was also induced by the two keratinocyte growth factors, transforming growth factor-alpha and epidermal growth factor, by the proinflammatory cytokine, tumor necrosis factor-alpha, but, somewhat surprisingly, not by interleukin-1 beta. The latent SL-2 proenzyme was isolated from 12-O-tetradecanoylphorbol-13-acetate-induced keratinocytes by immunoaffinity chromatography using a cross-reactive antibody raised against human SL-1. This procedure led to the recovery of a single M(r) 54,000 molecular species at a level of approximately 0.2 microgram/ml of culture medium. Amino-terminal sequencing identified the protein as SL-2 and verified the predicted signal sequence cleavage site. Conformational activation of latent SL-2 precursor by SDS gave rise to a full-length, uncleaved (M(r) 54,000) active form and at the same time exposed a cryptic thiol group. By contrast, organomercurial activation resulted in autolytic truncation of the molecule with loss of M(r) approximately 10,000 propeptide. SL-2 shared with (human fibroblast) SL-1 the ability to cleave casein, to "superactivate" fibroblast type procollagenase, and to form apparently binary, SDS-resistant complexes with tissue inhibitor of metalloproteinases-1.
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PMID:Cell type-specific regulation of SL-1 and SL-2 genes. Induction of the SL-2 gene but not the SL-1 gene by human keratinocytes in response to cytokines and phorbolesters. 834 17

Human pro-MMP-3 (pro-matrix metalloproteinase-3) was purified from three sources: articular cartilage and conditioned media from synovial fibroblasts and Chinese hamster ovary cells expressing recombinant pro-MMP-3. All three preparations reacted with two monoclonal antibodies specific for human fibroblast pro-MMP-3. Each preparation of active MMP-3 possessed properties identical to those previously reported for the cartilage acid metalloproteinase (MMP-6; Azzo and Woessner, J. F., Jr. (1986) J. Biol. Chem. 261, 5434-5441): an acid pH optimum of 5.3-5.5 for digestion of cartilage aggrecan; digestion of oxidized insulin B-chain at Ala14-Leu15 and Tyr16-Leu17 in a ratio of 3:1; and heat stability at neutral pH. Further characterization of MMP-3 establishes that the acid pH optimum for cartilage aggrecan is not due to substrate denaturation since the same optimum is found by viscosity assay, by SDS-polyacrylamide gel electrophoresis assay of G1 domain, and by digestion of aggrecan in fresh cartilage fragments in vitro. Fibronectin was also digested optimally at pH 5.5 and NH2-terminal sequence analysis revealed no pH change in a major proteolytic site of cleavage at the Pro689-Leu690 bond. The specificity constant kcat/Km is maximal at pH 5.5 as determined in a quenched fluorescence peptide assay. This is due to an increase in kcat at pH 5.5 without any substantial effect on Km. The affinity of MMP-3 for calcium is decreased about 10-fold at pH 5.3 compared to neutral pH. Finally, the neutral cartilage metalloproteinase is identified as 72-kDa pro-MMP-2 based on M(r), specificity of insulin B-chain cleavage, and reactivity with a specific polyclonal antibody to human MMP-2.
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PMID:Matrix metalloproteinase-3 (stromelysin-1). Identification as the cartilage acid metalloprotease and effect of pH on catalytic properties and calcium affinity. 840 46

Cathepsin D, matrix metalloproteinase (MMP)-2, MMP-3 (stromelysin), and MMP-9 were isolated from rat granulomatous tissues. HT1080 human fibrosarcoma cells and rheumatoid synovial cell CM. At acidic conditions, cathepsin D cleaved T-kininogen into small peptides and released Met-T-kinin-Leu (kinin precursor), but failed to release kinin. MMP-3 cleaved T-kininogen into a 57 kDa fragment as measured by SDS-PAGE and Western blot analysis using anti-T-kininogen antiserum. On the other hand, no degradation of T-kininogen occurred during incubation with MMP-2 or MMP-9100/1) at pH 7.5 for 7 h.
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PMID:Degradation of T-kininogen by cathepsin D and matrix metalloproteinases. 879 70

A series of isothiazolones that inhibit pro-(matrix metallo-proteinase) (proMMP) activation but do not inhibit the active enzyme are effective as cartilage protectants in bovine nasal cartilage organ culture, preventing interleukin-1 (IL-1)-induced proteoglycan (aggrecan) degradation without affecting its synthesis. These compounds were found to bind to prostromelysin (proMMP-3) in a non-dialysable and stoichiometric manner. Preincubation with cartilage-protectant isothiazolones prevented the binding of [14C]iodoacetamide to Cys75 of the MMP-3 propeptide, suggesting that the activity of these compounds involves their binding to the Cys75 of the MMP zymogen. Studies following chymotrypsin activation of proMMP-3 by SDS/PAGE indicated that altered processing of the 57 kDa zymogen to the active form occurred in the presence of compound. The 53 kDa intermediate seen on normal activation was not formed; instead a different intermediate appeared with a molecular mass of approx. 46 kDa. N-terminal sequence analysis indicated that this intermediate was formed by cleavage at the putative 4-aminophenylmercuric acid cleavage site. Importantly the 45 kDa active MMP-3 species formed in the presence of compound was one amino acid residue shorter than the native MMP-3. These results suggest that the inhibition of cartilage proteoglycan degradation by isothiazolones might be due to their ability to bind to the Cys75 in the propeptide region of the MMP zymogen and interfere with its normal activation process.
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PMID:Isothiazolones interfere with normal matrix metalloproteinase activation and inhibit cartilage proteoglycan degradation. 880 28

Membrane type matrix metalloproteinase 1 (MT-MMP1), a novel 63-kDa member of the matrix metalloproteinase family, is a membrane-anchored enzyme and an activator for gelatinase A. In addition to its C-terminal hydrophobic transmembrane domain, MT-MMP1 has an insertion of 11 amino acids between its propeptide and catalytic domain encrypted with a RRKR recognition motif for the paired basic amino acid cleaving enzyme, furin. In this report, we investigated whether the cleavage of the RRKR motif of MT-MMP1 by Golgi-associated furin is analogous to a similar enzyme activation mechanism observed with stromelysin-3. Mutant forms of MT-MMP1 were cotransfected into COS-1 cells with cDNAs for pro-gelatinase A and/or furin. Immunoprecipitation and immunoblotting using specific antibodies were employed to characterize cell proteins. Whereas furin readily cleaved soluble MT-MMP1 lacking the transmembrane domain (DeltaMT-MMP1), a soluble stromelysin-1/DeltaMT-MMP1 chimera without the RRKR basic motif was resistant to furin-induced cleavage. COS-1 cells cotransfected with wild type MT-MMP1 cDNA and furin cDNA demonstrated a 63-kDa protein (latent enzyme) on SDS-polyacrylamide gel electrophoresis rather than the anticipated lower molecular weight activated enzyme. Inhibition of furin activity with alpha1-protease inhibitorPittsburgh (a furin inhibitor) did not affect the pro-gelatinase A activation mechanism in COS-1 cells cotransfected with MT-MMP1 and pro-gelatinase A cDNAs. Furthermore, substitution of the RRKR motif of MT-MMP1 with alanine residues by site-directed mutagenesis resulted in the same 63-kDa protein without loss of pro-gelatinase A activation function. These data indicate that furin-induced activation of MT-MMP1 is not a prerequisite for pro-gelatinase A activation. The mechanism of activation of cell-bound MT-MMP1 remains to be elucidated.
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PMID:Membrane type matrix metalloproteinase 1 activates pro-gelatinase A without furin cleavage of the N-terminal domain. 893 68

The propeptide plus the catalytic domain of human fibroblast-type collagenase, stromelysin-1, and matrilysin were expressed in Escherichia coli to directly compare the properties of all three catalytic domains utilizing the same assays. Truncated fibroblast-type collagenase (mini-CL), truncated stromelysin-1 (mini-SL-1), and matrilysin, like their native counterparts, could be activated by organomercurials, trypsin, or SDS. The mini-CL and mini-SL-1 displayed catalytic properties similar to their native counterparts, except that the mini-CL could not cleave native type I collagen. The k(cat)/Km for matrilysin (355 microM(-1) h(-1)) on the synthetic Mca-peptide was much higher than that for mini-CL (69 microM(-1) h(-1)) or mini-SL-1 (23.6 microM(-1) h(-1)). Mini-SL-1 and matrilysin, but not mini-CL, were capable of superactivating collagenase thus increasing the rate of collagen cleavage. Mini-CL and mini-SL-1, but not matrilysin, were able to form SDS-stable complexes with TIMP-1 when co-incubated with an organomercurial and TIMP-1. The second-order rate constant (k(on)) for TIMP-1 inhibition of mini-CL and mini-SL-1 were similar, 0.635 x 10(5) M(-1) s(-1) and 1.52 x 10(5) M(-1) s(-1), respectively. The k(on) for TIMP-1 inhibition of matrilysin was lower (0.130 x 10(5) M(-1) s(-1)) supporting the observation that no SDS stable complexes were detected. This study demonstrates that these catalytic domains are distinct and play a major role in the specificity of these enzymes in regard to rate of catalysis, TIMP-1 binding, and superactivation of collagenase.
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PMID:Catalytic domain comparisons of human fibroblast-type collagenase, stromelysin-1, and matrilysin. 910 22

TIMP-4, a novel human tissue inhibitor of metalloproteinase, was identified and cloned (Greene, J., Wang, M., Raymond, L. A., Liu, Y. E., Rosen, C., and Shi, Y. E. (1996) J. Biol. Chem. 271, 30375-30380). In this report, the production and characterization of recombinant TIMP-4 (rTIMP4p) are described. rTIMP4p, expressed in baculovirus-infected insect cells, was purified to homogeneity by a combination of cation exchange, hydrophobic, and size-exclusion chromatographies. The purified protein migrated as a single 23-kDa band in SDS-polyacrylamide gel electrophoresis and in Western blot using a specific anti-TIMP-4 antibody. Inhibition of matrix metalloproteinase (MMP) activities by rTIMP4p was demonstrated in five MMPs. Enzymatic kinetic studies revealed IC50 values (concentration at 50% inhibition) of 19, 3, 45, 8, and 83 nM for MMP-1, MMP-2, MMP-3, MMP-7, and MMP-9, respectively. Purified rTIMP4p demonstrated a strong inhibitory effect on the invasion of human breast cancer cells across reconstituted basement membranes. Thus, TIMP-4 is a new enzymatic inhibitor in MMP-mediated extracellular matrix degradation and may have therapeutic potential in treating cancer malignant progression.
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PMID:Preparation and characterization of recombinant tissue inhibitor of metalloproteinase 4 (TIMP-4). 925 58

We describe the use of casting native collagen type I in SDS-polyacrylamide gel (collagen zymography) for the determination of interstitial collagenase. As with gelatin, the incorporation of collagen in the gels reduced protein migration and the need for making corrections for an accurate Mr evaluation. This method proved to be very sensitive: 0.1 pg of APMA-activated procollagenase could be detected, and specific levels of active gelatinase or stromelysin lower than 5 ng were inactive under our experimental conditions. It was used to demonstrate the increased expression of collagenase following treatment of human gingival fibroblasts with interleukin-1 beta; the amounts of enzyme quantified by either collagen zymography or immunodot blot assay are comparable.
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PMID:Collagen zymography as a sensitive and specific technique for the determination of subpicogram levels of interstitial collagenase. 945 6

Nine cholesteatomas, seven middle ear granulations and five deep meatal skin specimens were analysed for gelatinase activity at molecular weights corresponding to those of matrix metalloproteinase-1 (MMP-1) using SDS PAGE zymography. Gelatinase activity at 41-43 kDa and 45-47 kDa was investigated. Western blotting was employed using a primary monoclonal antibody to MMP-1 to provide a qualitative assessment of MMP-1. Western blotting was also used with a monoclonal antibody to MMP-3 to discover if MMP-3 gelatinase activity occurring around the molecular weight of MMP-1 may have contributed to the results. A significantly higher expression of activity was recorded in cholesteatoma and middle ear granulations at 45-47 kDa in comparison with deep meatal skin. Western blotting indices were to be present in all of the cholesteatoma specimens tested. Only one of the specimens (cholesteatoma) tested showed any MMP-3 presence.
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PMID:Matrix metalloproteinase-1 in cholesteatoma, middle ear granulations and deep meatal skin: a comparative analysis. 988 4


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