Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.4.24.3 (collagenase)
18,340 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The purification and cloning of a novel metalloproteinase inhibitor (MI or TIMP-2) related to tissue inhibitor of metalloproteinases (TIMP) has been recently described by our laboratory (DeClerck, Y.A., Yean, T. D., Ratzkin, B.J., Lu, H.S., and Langley, K.E. (1989) J. Biol. Chem. 264, 17445-17453; Boone, T.C., Johnson, M.J., DeClerck, Y.A., and Langley, K.E. (1990) Proc. Natl. Acad. Sci. U. S. A. 87, 2800-2804). We have transfected Chinese hamster ovary cells with a vector containing human MI/TIMP-2 cDNA and purified recombinant-derived MI/TIMP-2 (rMI/rTIMP-2) from the conditioned medium of such cells. We have investigated the inhibitory activity of rMI/rTIMP-2 toward rabbit fibroblast interstitial collagenase. The inhibition of activated collagenase by rMI/rTIMP-2 is stoichiometric and consistent with the formation of a 1:1 molar ratio complex. In addition to blocking the activated enzyme, rMI/rTIMP-2 inhibits the conversion of 52-kDa procollagenase to the 42-kDa active enzyme initiated by organomercurials. When plasmin is used as activator, rMI/rTIMP-2 does not inhibit the plasmin-mediated conversion of the 52-kDa proenzyme to the 46-kDa inactive intermediate but blocks further conversion of the 46-kDa intermediate to the 42-kDa active enzyme. The data indicate that rMI/rTIMP-2 blocks the autoproteolytic activation of procollagenase. Also, rMI/rTIMP-2 forms complexes with the 52-kDa procollagenase, the 46-kDa intermediate, and with the 42-kDa activated enzyme which are stable to sodium dodecyl sulfate (SDS), such that the complexes can be visualized by SDS-polyacrylamide gel electrophoresis. It appears that the formation of a SDS-stable complex with procollagenase requires an initial conformational change of the procollagenase brought about by organomercurials or by plasmin cleavage. The data suggest that MI/TIMP-2 may be able to control the extracellular action of certain metalloproteinases not only at the level of the activated enzyme but also at the level of proenzyme activation.
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PMID:Inhibition of autoproteolytic activation of interstitial procollagenase by recombinant metalloproteinase inhibitor MI/TIMP-2. 184 92

Fibroblast-type collagenase, a neutral secretory metalloproteinase capable of cleaving interstitial collagen types I-III, is expressed by a number of different cell types including fibroblasts, macrophages, osteoblasts, and keratinoyctes. To elucidate the secretory pathway of this enzyme, we examined the ultrastructural localization of this metalloproteinase in cultured human gingival fibroblasts, particularly the routing of the enzyme from the Golgi cisternae to the cell surface utilizing rabbit polyclonal antibodies raised against human fibroblast (pro) collagenase. For this purpose, one percent glutaraldehyde followed by gentle permeabilization with saponin gave superior preservation of both cellular morphology and intracellular antigenicity. At the light microscopic level, the reacting antibodies visualized by immunofluorescence and immunoperoxidase staining were localized intracellularly in the perinuclear region reflecting the Golgi apparatus. Immunoelectronmicroscopy using the pre-embedding technique and peroxidase or immunogold staining revealed electron dense label in large vacuoles indicating extended cisternae of the Golgi field. Vesicles were noted leaving the plasma membrane in long extensions. Moreover, intact vesicle containing the antibody reaction product appeared outside the membrane. In addition, most extracellular vesicular structures appeared empty of label suggesting that the collagenase had been liberated into the extracellular space. The latter observation was supported by the fact that the label was found also on the extracellular surface of the cells indicating a (re)association of collagenase with the outer cell membrane. These data demonstrate that the pathway of interstitial collagenase in human gingival fibroblasts is similar to that of other secretory proteins.
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PMID:Intracellular secretory pathway and ultrastructural localization of interstitial procollagenase in human gingival fibroblasts. 196 15

Interstitial collagenases (matrix metalloproteinase-1, EC 3.4.24.7), isolated from extracts of inflamed human gingiva, gingival crevicular fluid and saliva were characterized for their molecular weight, proteolytic and non-proteolytic activation and substrate specificity against soluble collagen types I, II and III. All three collagenases had Mr of 70 K. The enzymes existed predominantly in a latent form that could be activated by aminophenylmercuric acetate, gold thioglucose and hypochlorous acid. Among serine proteases tested, trypsin, chymotrypsin, neutrophil cathepsin G and a combination of trypsin and human gingival fibroblast prostromelysin activated gingival and salivary interstitial collagenases. Plasmin and plasma kallikrein, however, were relatively ineffective activators. The collagenases degraded soluble type I and II collagens at apparently equal rates but considerably faster than they did type III collagen. These findings suggest that the characteristics of interstitial collagenases found in inflamed human gingiva, gingival crevicular fluid and saliva are consistent with those of human neutrophil interstitial collagenase rather than the fibroblast-type interstitial collagenase. Thus, neutrophils are suggested to be the main source of such enzymes in inflamed human gingiva, crevicular fluid and saliva during adult periodontitis.
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PMID:The role of gingival crevicular fluid and salivary interstitial collagenases in human periodontal diseases. 196 17

We have identified and sequenced a cDNA encoding human neutrophil collagenase from a lambda gt11 cDNA library constructed from mRNA extracted from the peripheral leukocytes of a patient with chronic granulocytic leukemia. The library was screened with an oligonucleotide probe constructed from the putative zinc-binding region of fibroblast collagenase. Eleven positive clones were identified, of which the one bearing the largest insert (2.2 kilobases (kb)) was sequenced. From the nucleotide sequence of the 2.2-kb cDNA clone we have deduced a 467-amino acid sequence representing the entire coding sequence of the enzyme. The deduced protein was confirmed as neutrophil collagenase by conformity with the amino-terminal sequence analyses of three tryptic peptides of purified neutrophil collagenase. The cDNA clone hybridizes to a 3.3-kb mRNA present in RNA extracted from human bone marrow but did not hybridize with RNA isolated from U937 cells induced to differentiate with phorbol myristate acetate. Neutrophil collagenase was found to possess 57% identity with the deduced protein sequence for fibroblast collagenase with 72% chemical similarity. Certain regions of the molecule, including the putative zinc-binding region, are highly conserved. When compared with the published sequence for fibroblast collagenase, neutrophil collagenase contains four additional sites for glycosylation. Medium from COS-7 cells transfected with a pcDNA1 eucaryotic expression vector containing cDNA for neutrophil collagenase degraded type I collagen into the three-quarter, one-quarter fragments characteristic of mammalian interstitial collagenase activity. Thus, definitive evidence based on the cDNA sequence confirms the neutrophil collagenase is a distinct gene product and a member of the family of matrix metalloproteinases.
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PMID:Human neutrophil collagenase. A distinct gene product with homology to other matrix metalloproteinases. 216 2

Connective-tissue cells produce a family of metalloproteinases which, once activated, can degrade all the components of the extracellular matrix. These potent enzymes are all inhibited by the tissue inhibitor of metalloproteinases (TIMP), and it was thought that the levels of this inhibitor controlled the extracellular activity of these enzymes. We recently detected a new metalloproteinase inhibitor present in culture media of WI-38 fibroblasts. The inhibitor, named 'large inhibitor of metalloproteinases' (LIMP), can be separated from TIMP by gel filtration on Ultrogel AcA 44, where it is eluted with an apparent Mr of 76,000. A portion of this inhibitor-containing peak binds to concanavalin A-Sepharose, indicating that at least some of the inhibitor contains carbohydrate. LIMP inhibits collagenase (MMP-1), stromelysin (MMP-3) and gelatinase (MMP-2) in a dose-dependent fashion. Collagenase forms tight-binding complexes with LIMP, which can be separated from free collagenase on gel-filtration columns. The complex is eluted with Mr 81,600 (AcA 44) or Mr 60,000 (Superose 12). This complex is larger than that formed between collagenase and TIMP, which has Mr 52,800 (Aca 44) or 41,000 (Superose 12). Polyclonal antibody to TIMP does not recognize LIMP by immunoblotting, and will not block the inhibition of collagenase by LIMP, showing that LIMP is not a multimeric form of TIMP. The role of this new inhibitor in connective-tissue breakdown studies and its relationship to previously described inhibitors of metalloproteinases is discussed.
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PMID:Identification of a new metalloproteinase inhibitor that forms tight-binding complexes with collagenase. 216 93

We have investigated the effect of interleukin 6 (IL-6) on the synthesis of tissue inhibitor of metalloproteinases (TIMP) and matrix metalloproteinases (MMPs), collagenase (MMP-1) and stromelysin (MMP-3) using human skin and uterine cervical fibroblasts. IL-6 did not modulate the expression of MMPs by these fibroblasts, but the production of TIMP was enhanced by IL-6 in a dose dependent manner, whereas IL-1 stimulated the production of both MMPs and TIMP. The combination of IL-6 and IL-1 further augmented IL-1-induced MMPs and TIMP production. The results provide the first evidence that IL-6 participates in the catabolism of the extracellular matrix components by modulating the effects of IL-1 on MMPs and TIMP synthesis as well as its direct effects on the synthesis of TIMP by connective tissue cells.
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PMID:Interleukin 6 enhances the production of tissue inhibitor of metalloproteinases (TIMP) but not that of matrix metalloproteinases by human fibroblasts. 216 9

A full-length complementary DNA (cDNA) for interstitial collagenase was isolated from an A2058 melanoma cDNA library using the pCD-X Okayama-Berg vector. The tumor interstitial collagenase cDNA was sequenced and compared to the published sequences for human fibroblast collagenase. The sequence for the tumor collagenase has two DNA base pairs which differ from the sequence of normal fibroblast collagenase. Restriction enzyme digestion of a specific DNA fragment produced by polymerase chain reaction amplification of genomic DNA from human placenta resolves a discrepancy in the previously reported DNA and amino acid sequences for the fibroblast collagenase. A high level of expression of interstitial collagenase message was found in human A2058 melanoma cells by Northern blot analysis, and this level was slightly increased by phorbol ester (phorbol myristate acetate) stimulation. Interstitial collagenase mRNA expression was significantly decreased by treatment with either transforming growth factor-beta 1 or retinoic acid in A2058 melanoma cells. A high level of the collagenase protein secreted into conditioned media was identified by Western blotting. As shown by gelatin zymogram analysis interstitial collagenase was one of at least two metalloproteinases secreted by this same cell line. Thus, human melanoma cells can directly produce interstitial collagenase without a requirement for host cell interaction.
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PMID:Cloning and characterization of human tumor cell interstitial collagenase. 216 56

We have recently presented biochemical evidence for collagen and gelatin degrading activities associated with plasma membranes of various human cancer cell lines. In this report we describe the localization of interstitial collagenase at the basal plasma membrane of the human pancreatic cancer cell line RWP-I, using immunofluorescence and ultrastructural immunogold labeling techniques. Collagenase was expressed on the extracellular face of the plasma membrane. Furthermore, the immunogold labeling was concentrated on the long, finger-like microvillous projections typically seen on the basal cell surface, while the short, brush-like projections characteristic of the apical cell surface were unlabeled. When the cytoplasmic face of the membrane was made accessible, the number of reactive sites increased markedly, indicating a high concentration of enzyme at the inner surface of the plasma membrane. When plasma membrane fractions of RWP-I cells were prepared by differential centrifugation, high salt washes virtually failed to extract collagenase activity from the membrane, while detergent extraction with n-octyl glucoside, a detergent used in the purification of integral membrane proteins, yielded soluble collagenase activity. When detergent extracted membrane fractions were passed over an anticollagenase immunoaffinity column, collagenase was specifically bound, as demonstrated by the TCA and TCB degradation of type I collagen by the bound material. Gelatinolytic activity did not bind to the column. Furthermore, immunoprecipitation of 125I-labeled detergent extracts of tumor membranes yielded a single Mr 55,000 band consistent with the zymogen form of the connective tissue collagenase. These morphological and biochemical findings suggest that collagenase is a tightly associated component of the basal plasma membrane, where it occupies a strategic location for directional proteolysis during cell migration and invasion.
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PMID:Localization of collagenase at the basal plasma membrane of a human pancreatic carcinoma cell line. 217 14

Interferon-gamma (IFN-gamma) is a lymphokine that activates mononuclear phagocytes. To test the hypothesis that IFN-gamma might have important effects upon the ability of human mononuclear phagocytes to degrade extracellular matrix, we have studied the action of this cytokine on the production of metalloproteinases and the counterregulatory tissue inhibitor of metalloproteinases (TIMP) by the human alveolar macrophage. We have found that IFN-gamma potently and selectively suppresses the lipopolysaccharide-induced production of two metalloproteinases--interstitial collagenase and stromelysin--by 50-90% at doses greater than or equal to 10 U/ml. The synthesis of TIMP and 92-kD type IV collagenase was also diminished by IFN-gamma, but these responses required 50- to 100-fold higher concentrations of the cytokine. All doses of IFN-gamma increased total and secreted protein synthesis slightly, indicating a highly specific effect on metalloenzyme biosynthesis. Inhibition of metalloproteinase expression occurred at a pretranslational level, as evidenced by parallel reductions in enzyme biosynthesis and collagenase-specific steady-state mRNA levels. Interestingly, the effect of IFN-gamma on metalloenzyme production was not readily reversible. Therefore, while IFN-gamma activates the macrophage and renders it tumoricidal, this enhanced function appears to be attained at the expense of the cell's capacity to degrade extracellular matrix.
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PMID:Immune modulation of metalloproteinase production in human macrophages. Selective pretranslational suppression of interstitial collagenase and stromelysin biosynthesis by interferon-gamma. 217 Apr 47

The lectin concanavalin A (ConA) causes fibroblasts to acquire an arborized morphology and to express elevated levels of collagenase. The temporal and mechanistic aspects of ConA regulation of matrix metalloproteinases (MMPs) and the tissue inhibitor of matrix metalloproteinases (TIMP) were characterized in early passage human fibroblasts. Collagenase (MMP-1), measured by functional assays in the absence of TIMP and also as immunoprecipitated [35S]methionine-labeled protein, was increased 10-20-fold following ConA (20 micrograms/ml, 2 x 10(-7) M) treatment for 24-72 h, with active collagenase comprising approximately 20% of the total collagenase activity. By comparison, MMP-2 (72-kDa gelatinase; molecular mass, 72 kDa, +dithiothreitol; 66 kDa, -dithiothreitol), analyzed by enzymography and following affinity purification, was increased less than 2-fold by ConA and was present entirely as an activated, 61-kDa (+dithiothreitol; 59 kDa, -dithiothreitol) form. Northern hybridization analyses revealed that ConA elevated the steady-state mRNA levels for MMPs; collagenase mRNA increased approximately 16-fold, MMP-2 increased 2-fold, and Pump-1, a recently described MMP gene, was induced. Concomitantly, a 10-fold reduction in TIMP protein and mRNA levels by ConA occurred. In comparison, 12-O-tetradecanoylphorbol-13-acetate (50 ng/ml, 8 x 10(-8) M), which also stimulates collagenase expression strongly (greater than 30-fold), elevated TIMP protein and mRNA levels (2- and 3-fold, respectively) and did not affect MMP-2 expression. The changes in MMP and TIMP mRNA levels induced by ConA were blocked by the protein synthesis inhibitor cycloheximide, and the half-lives of collagenase and MMP-2 mRNAs (53 and 46 h, respectively) were unaffected, indicating that ConA exerts its effects transcriptionally, through pathways requiring de novo protein synthesis. Increased transcription of the mmp genes was confirmed by nuclear run-on analyses; mmp-1 transcription was increased by greater than 25-fold, mmp-2 by approximately 3-fold, and Pump-1 by approximately 7-fold. In contrast, Timp gene transcription was reduced by approximately 80%, revealing reciprocal regulation of MMPs and TIMP during the induction of a resorptive cell phenotype. Decreased amounts of collagen and fibronectin, but not of SPARC (secreted protein, acidic and rich in cysteine) in the conditioned medium was the result of MMP activity since steady-state mRNA levels and transcription of the respective matrix protein genes were unaffected by ConA.
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PMID:Concanavalin A produces a matrix-degradative phenotype in human fibroblasts. Induction and endogenous activation of collagenase, 72-kDa gelatinase, and Pump-1 is accompanied by the suppression of the tissue inhibitor of matrix metalloproteinases. 217 35


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