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)

Type X collagen was extracted with 1 M NaCl and 10 mM dithiothreitol at neutral pH from fetal human growth plate cartilage and purified to homogeneity by gel filtration and anion-exchange chromatography. The purified protein migrates in SDS/polyacrylamide gels with an apparent Mr of 66,000 under reducing conditions, and as a high-Mr oligomer under non-reducing conditions. Purified collagenase digests most of the molecule; pepsin digestion at 4 degrees C decreases the Mr of the monomer to 53,000. A rabbit antiserum was raised against purified human type X collagen; the IgG fraction was specific for this collagen by criteria of ELISA and immunoblotting after absorption with collagen types I, II, VI, IX and XI. Immunohistological studies localized type X collagen exclusively in the zone of hypertrophic and calcifying cartilage.
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PMID:Isolation of human type X collagen and immunolocalization in fetal human cartilage. 201 80

A monoclonal antibody against a pepsin-soluble mammalian type I collagen has been produced. This antibody, subclass IgG1, kappa, was specific for type I collagen and did not cross-react with a range of other collagen types or connective tissue proteins. The epitope recognized by the antibody was dependent upon an intact triple-helical structure for the collagen, and was shown by rotary shadowing and by immunoblotting of collagenase-derived fragments to be near the C-terminal of the pepsin-soluble collagen. Although the antibody had a low affinity, with Kd = 4 x 10(-7) M, it could be used for immunohistology of tissue sections and for studies of collagen produced by cells in culture. The antibody, which was raised against human collagen, also recognized type I collagens from certain other species, including calf, pig, sheep, goat and dog.
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PMID:Characterisation of a monoclonal antibody against native human type I collagen. 210 19

The digital flexor tendons of the neonate and adult horse have been compared with respect to variation in extracellular matrix composition along their length. Two pepsin-sensitive, acetic acid soluble proteins, molecular weight (Mr) 52 kD (np 52) and Mr 54 kD (np 54), were prominent throughout the length of neonatal tendons. In adult tendon, np 52 and np 54 were less abundant and restricted to the cannon (metacarpal) region. In contrast, a single pepsin- and collagenase-resistant protein of Mr 55 kD (fp 55) was exclusive to the fetlock (metacarpophalangeal joint) region regardless of age, although more distinct in the adult. Pepsin extracted fp 55 precipitated at 2.0 M sodium chloride: 0.5 M acetic acid and was further purified to homogeneity by bacterial collagenase digestion. Analysis of fp 55 amino acid composition revealed the presence of a large proportion of glycine residues (379 of 1001), suggesting a possible homology with the collagen family. These data demonstrate that the composition of equine digital flexor tendons varies with age, is heterogeneous along its length, and suggests that variation in tendon extracellular matrix composition is influenced by functional requirements.
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PMID:Age- and position-related heterogeneity of equine tendon extracellular matrix composition. 211 5

The dermis of a child with Ehlers-Danlos syndrome type IV (EDS-IV) contained about 11% of the normal amount of type III collagen and cultured dermal fibroblasts produced a reduced amount of type III procollagen which was secreted poorly. Type III collagen produced by these cells contained normal and abnormal alpha-chains and cyanogen bromide peptides. The site of the structural defect in the abnormal alpha 1 (III) chains was localized to the region of Met797, which is at the junction of the two carboxyl-terminal CB5 and CB9 cyanogen bromide peptides. Chemical cleavage of heteroduplexes formed between EDS-IV mRNA and a normal cDNA clone covering the CB5 and CB9 region showed that about 100 nucleotides were mismatched. Sequencing of amplified and cloned cDNA spanning the mutant region revealed a 108 nucleotide deletion corresponding to amino acid residues Gly775 to Lys810. The deleted nucleotide sequence corresponded to sequences that, by analogy to the organization of the type I collagen genes, should be precisely encoded by exon 41 of the COL3A1 gene. Sequencing of amplified genomic DNA, prepared using disimilar amounts of primers specific for exons 41 and 42, displayed a base substitution (G-to-A) in the highly conserved GT dinucleotide of the 5' splice site of intron 41. Normal sequences were also obtained from the normal allele. It is likely that the GT-to-AT transition at the splice donor site of intron 41 generated an abnormally spliced mRNA in which sequences of exon 40 and 42 were joined together with maintenance of the reading frame. The corresponding peptide deletion included the cyanogen bromide cleavage site Met797-Pro798 and the mammalian collagenase cleavage site at Gly781-Ile782. These losses account for the resistance of EDS-IV collagen to cyanogen bromide and mammalian collagenase digestion. Cultured fibroblasts produced normal homotrimer, mutant homotrimer, and mixed heterotrimer type III collagen molecules. The mutant homotrimer molecules were the major pepsin-resistant species and about 69% of the alpha 1(III) mRNA was in the mutant form.
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PMID:A base substitution at a splice site in the COL3A1 gene causes exon skipping and generates abnormal type III procollagen in a patient with Ehlers-Danlos syndrome type IV. 214 68

We describe a method for maintaining neonatal pig pancreatic isletlike cell clusters (as pseudo-islets) embedded in a collagen gel matrix for long periods. The pseudo-islets were formed from single cells of pig pancreas maintained in a suspension culture and then embedded in pepsin-solubilized type I collagen. When the pseudo-islets were cultured in the collagen matrix, the amount of collagen in the culture decreased gradually during the culture period as soluble hydroxyproline-containing material accumulated in the medium. A low concentration of collagen (0.16%) degraded the collagen gels more rapidly than did high concentrations of collagen (0.64%). The degradation of collagen depended both on the number of pseudo-islets embedded in the gel matrix and on the culture conditions used to maintain them. With added nicotinamide, the accumulation of hydroxyproline decreased in the medium and the structure of the gel matrix was well maintained. Hydrocortisone or a specific inhibitor of collagenase did not decrease the solubilization of embedded pseudo-islet cultures and did not help to maintain their structure. These observations indicate the possible utility of long-term maintenance of pseudo-islets in collagen gel matrix in the presence of nicotinamide.
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PMID:Maintenance of embedded pig pancreatic pseudo-islets in a collagen gel matrix: study of the effect of hydrocortisone, a collagenase inhibitor, and nicotinamide on collagenolysis and the morphogenesis of pancreatic islet-cells in collagen gel matrix. 216 Sep 24

A novel polypeptide with a molecular weight of 17 kd (17k protein) was identified in bone marrow cell cultures. The synthesis of 17k protein is elevated in cell cultures maintained under Dexter conditions, which support myelopoiesis. The predominance of macrophages in the stromal layer of these cultures and the observation that a mouse myelomonocytic cell line P388D1 is capable of synthesizing large amounts of 17k protein led us to the study of its synthesis by bone marrow macrophages. Metabolic labeling with [14C]proline and partial amino acid analysis of 17k protein demonstrated that the polypeptide contains relatively high amounts of proline and is also sensitive to degradation with bacterial collagenase. However, no hydroxyproline is detectable in 17k protein, and it is extensively degraded with bacterial collagenase. However, no hydroxyproline is detectable in 17k protein, and it is extensively degraded by proteolysis with pepsin, using conditions under which collagen triple helices are resistant to degradation, suggesting that collagen-like structures are not contained in 17k protein. This polypeptide is found predominantly in the cellular layers of bone marrow macrophage cultures. Incorporation of [14C]proline into 17k protein is diminished by increasing concentrations of colony-stimulating factor 1 (CSF-1). The 17k protein may be involved in macrophage proliferation because its synthesis is inhibited by CSF-1, which is required for the maintenance of bone marrow macrophages in vitro.
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PMID:A 17-kd polypeptide, sensitive to bacterial collagenase, is synthesized by bone marrow macrophages. 216 40

Collagen was extracted from human adult bone by limited pepsin digestion and collagen types were purified by consecutive salt precipitation first under neutral and then under acid conditions. In SDS/PAGE, all collagen type I preparations showed a protein band [alpha 1s(I)] migrating between alpha 1(I) and alpha 2(I) as well as a band [alpha 2s(I)] migrating in front of alpha 2(I). The collagenous nature of the pepsin-stable alpha 1s(I) protein was clearly demonstrated by digestion with human-leucocyte-derived collagenase, immunoblotting with antibodies against collagen type I and amino acid analysis. Partial amino acid sequencing of alpha 1(I) and alpha 1s(I) identified alpha 1s(I) as a shortened alpha 1(I) chain due to a specific cleavage site between residues Leu95 and Asp96 which is in close vicinity to the hydroxylysine-derived crosslink at position 87. In circular dichroism, the proportion of thermally labile collagen molecules was proportional to the amount of shortened alpha 1(I) and alpha 2(I) chains, respectively. The melting temperature was found to be 36 +/- 0.5 degrees C as judged from circular dichroism and susceptibility to proteolysis. Our data provide clear evidence that a shortened alpha 1-derived collagen chain can be extracted from human adult bone whereas it is hardly found in human skin. The unique cleavage site might provide important information about the collagen I molecule embedded in the calcified matrix of human bone.
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PMID:A critical crosslink region in human-bone-derived collagen type I. Specific cleavage site at residue Leu95. 216 12

The shrinkage temperature (Ts) and the pepsin-solubilizability of collagen fibrils in bone matrix obtained from decalcified femur diaphysis from 2-, 5-, 15- and 25-month-old rats were found to decrease with age. Digestion with human fibroblast collagenase dissolved less than half of the collagen, whereas sequential treatment by pepsin followed by collagenase resulted in its complete dissolution. This result shows that collagenase and a telopeptide-cleaving enzyme, when acting in an appropriate sequence, have a great potential for the degradation of bone collagen. The 'melting' profile of the pepsin-solubilized collagen showed a biphasic transition with transition peak at 35.9 degrees C and 40.8 degrees C. With increasing age an increasing proportion of the collagen 'melted' in the transition peak at 35.9 degrees C (pre-transition), and the 'melting' temperature (Tm) of the collagen decreased in parallel with Ts in relation to age. Both Ts and Tm decreased by 3 degrees C in the age span investigated. The age-related change in Ts could therefore be accounted for by the decrease in molecular stability. The collagenase-cleavage products of the bone collagen obtained by the sequential treatment with pepsin and collagenase showed only one peak transition (at 35.1 degrees C), and the Tm for the products was independent of age. The results indicate that the pre-transition for the pepsin-solubilized collagen is due to an age-related decrease in thermal stability may have implications for the mechanical strength and turnover of the bone collagen. In contrast with bone collagen, soft-tissue collagen showed neither the age-dependency of thermal stability nor the characteristic biphasic 'melting' profile.
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PMID:Age-related thermal stability and susceptibility to proteolysis of rat bone collagen. 217 74

In the present study, the method of collagenase-pepsin prepared cell suspension of human placental villi from early (10-12 weeks) and term (38-40 weeks) gestation cultured in vitro combined with progesterone radioimmunoassay was employed. The results indicated that: 1. In the placenta villi cells from early and term gestation in vitro, both exogenous and endogenous hCG showed a stimulatory effect on progesterone secretion, and the effect was approximately proportional to the concentration of the exogenous hCG added. 2. In the placenta villi cells from term gestation in vitro, after addition of sufficient rabbit antihCG IgG to the culture medium, LHRH-A exhibited no obvious influence on this hCG-independent progesterone secretion. However, in the absence of rabbit anti-hCG IgG in the culture medium, LHRH-A showed a stimulatory action on progesterone secretion probably via its stimulatory effect on hCG secretion which could subsequently increase the progesterone secretion. 3. In the placenta villi cells from early gestation, LHRH-A exhibited an inhibitory effect on both hCG-independent and hCG-dependent progesterone secretion.
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PMID:[The effects of HCG and LHRH-A on progesterone secretion by human placenta villi cells of early and term gestation in vitro]. 228 76

Circumstantial evidence in several previous studies has suggested that sea urchin embryo micromeres, the source of primary mesenchyme cells which produce the embryonic skeleton, contribute to the extracellular matrix of the embryo by synthesizing collagen. A direct test of this possibility was carried out by culturing isolated micromeres of the sea urchin Stronglyocentrotus purpuratus in artificial sea water containing 4% (v/v) horse serum. Under these conditions the micromeres divide and differentiate to produce spicules with the same timing as intact embryos. Collagen synthesis was determined by labeling cultures with [3H]proline or [35S]methionine and the medium and cell layer were assayed for collagen. The results indicate that by the second day in culture micromeres synthesize and secrete a collagenase-sensitive protein doublet with a molecular weight of about 210 kDa. Densitometry indicates a 2:1 ratio of the respective bands in the doublet which is characteristic of Type I collagen. The doublet is insensitive to digestion with pepsin. This differential sensitivity is characteristic of collagen. Over 90% of the collagen synthesized by micromeres is soluble in the seawater culture medium. On days 2-4 in culture, collagen accounts for 5% of the total protein synthesized and secreted. Additional collagenase-sensitive bands are noted at 145 and 51 kDa. The relationship of the described collagen metabolism to previously characterized collagen gene expression in sea urchin embryos is discussed.
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PMID:The synthesis and secretion of collagen by cultured sea urchin micromeres. 232 72


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