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:3.1.6.4 (chondroitinase)
2,039 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A cytochemical study was performed on the lamprey ventral aorta with special reference to disulfide and sulfhydryl groups of microfibrils, using the high-iron diamine-thiocarbohydrazide-silver proteinate (HID-TCH-SP) method combined with several other types of treatment. The HID-TCH-SP staining observed was classified into three categories: 1) weak staining in the periphery of collagen fibrils, 2) moderate staining in the boundaries of collagen fibrils, microfibrils and smooth muscle cells, and 3) intense staining of microfibrils. The first and second categories of staining were considered to represent chondroitin and/or heparan sulfate because of sensitivity of the staining to chondroitinase ABC (ChABC) and its specific localization. By contrast, the third category of staining was considered to represent disulfide and sulfhydryl groups of microfibrillar glycoprotein, because it was disclosed only after Oxone oxidation or thiosulfation and was not removed by ChABC digestion. Although this staining reactivity was not apparently altered by SH blockade prior to oxidation or thiosulfation, it was markedly diminished or completely inhibited by S-S reduction followed by SH blockade. These results indicate that lamprey aortic microfibrils contain more S-S groups than SH groups.
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PMID:Cytochemical detection of disulfide and sulfhydryl groups in lamprey aortic microfibrils. 169 75

Chondrons have recently been extracted from adult articular cartilages and techniques developed to study their structure and composition in isolation. This study introduces methods to immobilize isolated canine chondrons in thin layers of agarose gel for immunohistochemistry and future in vitro studies. An antibody to Type VI collagen which stained the chondron in suspension was used to successfully validate the system and its feasibility for immunoelectron microscopy. Monoclonal and polyclonal antibodies to a variety of epitopes on the proteoglycan molecule were tested on fresh and fixed plugs cored from chondron-agarose gels. Plugs were immunolabeled with peroxidase-diaminobenzidine before or after digestion with testicular hyaluronidase or chondroitinase ABC. Trypsin/chymotrypsin were used to challenge epitopes of the core protein. The results indicate that epitopes to keratan sulfate, chondroitin sulfate, hyaluronate binding region, and core protein are localized in the chondron. Consistent staining was found in the tail and interconnecting segments between chondrons, whereas staining of the pericellular matrix and capsule adjacent to the chondrocyte varied according to the enzyme pre-treatment employed. We conclude that isolated chondrons are rich in proteoglycan monomer, which is particularly concentrated in the tail and interconnecting segments of the chondron where it could function to protect and stabilize the chondrocyte.
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PMID:Chondrons from articular cartilage. (IV). Immunolocalization of proteoglycan epitopes in isolated canine tibial chondrons. 171 45

In the course of an ultrastructural cytochemical study of intracellular sulphated proteoglycans involving the addition of cetylpyridinium chloride in the primary aldehyde fixative, a remarkable ultrastructural preservation of the collagen-associated sulphated proteoglycans was observed. Together with the preservation of their localization among the collagen fibrils (with, for some of them, a 50 nm periodic association with d-bands) and of their native elongated shape, previously observed under similar technical conditions, these stick-shaped and chondroitinase ABC-sensitive proteoglycans exhibited a typical pattern with several dense longitudinal parallel tracks (periodicity: 3-4 nm) not described as yet. Readily observable without high iron diamine-staining, the morphology of these cetylpyridinium chloride-precipitated and collagen-associated polyanions was particularly enhanced after incubation in the diamine solution which ascertained their sulphate content. Such a common ultrastructural organization with parallel tracks for both intracellular (i.e., in eosinophilic polymorphonuclear cells and Kurloff cells) and extracellular CPC-precipitated sulphated proteoglycans could correspond to intrinsic properties of the complexed molecules and could be related to 'double track' proteoglycans observed under other technical conditions in basement membranes.
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PMID:Collagen-associated sulphated proteoglycans. Ultrastructure after formaldehyde-cetylpyridinium chloride fixation. 172 36

Chondroitin sulfate proteoglycans (CSPGs) are the major class of proteoglycans synthesized by mouse uterine stroma in vitro (Jacobs, A. L., and Carson, D. D. (1991). J. Biol. Chem. 266, 15,464-15,473). In the present study, stromal CSPGs were isolated and examined with regard to their ability to bind to specific extracellular matrix (ECM) components. Of a variety of ECM components tested, only collagen type I formed stable complexes with stromal CSPGs in both solid phase and solution binding assays. Proteolytic digestion of the CSPGs did not affect binding and suggested that the protein cores did not participate directly in binding. Furthermore, free chondroitin sulfate polysaccharides do not compete effectively in the binding assays. Therefore, interactions with multiple CS chains and/or the higher charge density afforded by intact CSPGs appear to be required for retention by collagen type I. Intact CSPGs were examined for their ability to modulate embryo attachment and outgrowth in vitro on fibronectin- or collagen type I-coated surfaces. In both cases, intact CSPGs, but not their constituent protein cores or polysaccharides, inhibited both the rate and the extent of outgrowth formation. In addition, embryo outgrowth on stromal ECM was enhanced by predigestion with chondroitinase. Addition of exogenous CSPG markedly retarded embryo outgrowth on stromal matrix. Collectively, these data indicate that stromal cell-derived CSPGs are retained by collagen type I in the stromal interstitial ECM where these molecules may attenuate trophoblast invasive behavior.
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PMID:Uterine stromal cell chondroitin sulfate proteoglycans bind to collagen type I and inhibit embryo outgrowth in vitro. 173 Mar 87

The lymphocyte-high endothelial venule (HEV) cell interaction is an essential element of the immune system, as it controls lymphocyte recirculation between blood and lymphoid organs in the body. This interaction involves an 85-95-kD class of lymphocyte surface glycoprotein(s), CD44. A subset of lymphocyte CD44 molecules is modified by covalent linkage to chondroitin sulfate (Jalkanen, S., M. Jalkanen, R. Bargatze, M. Tammi, and E. C. Butcher. 1988. J. Immunol. 141:1615-1623). In this work, we show that removal of chondroitin sulfate by chondroitinase treatment of lymphocytes or incubation of HEV with chondroitin sulfate does not significantly inhibit lymphocyte binding to HEV, suggesting that chondroitin sulfate is not involved in endothelial cell recognition of lymphocytes. Affinity-purified CD44 antigen was, on the other hand, observed to bind native Type I collagen fibrils, laminin, and fibronectin, but not gelatin. Binding to fibronectin was studied more closely, and it was found to be mediated through the chondroitin sulfate-containing form of the molecule. The binding site on fibronectin was the COOH-terminal heparin binding domain, because (a) the COOH-terminal heparin-binding fragment of fibronectin-bound isolated CD44 antigen; (b) chondroitin sulfate inhibited this binding; and (c) finally, the ectodomain of another cell surface proteoglycan, syndecan, which is known to bind the COOH-terminal heparin binding domain of fibronectin (Saunders, S., and M. Bernfield. 1988. J. Cell Biol. 106: 423-430), inhibited binding of CD44 both to intact fibronectin and to its heparin binding domain. Moreover, inhibition studies showed that binding of a lymphoblastoid cell line, KCA, to heparin binding peptides from COOH-terminal heparin binding fragment of fibronectin was mediated via CD44. These findings suggest that recirculating lymphocytes use the CD44 class of molecules not only for binding to HEV at the site of lymphocyte entry to lymphoid organs as reported earlier but also within the lymphatic tissue where CD44, especially the subset modified by chondroitin sulfate, is used for interaction with extracellular matrix molecules such as fibronectin.
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PMID:Lymphocyte CD44 binds the COOH-terminal heparin-binding domain of fibronectin. 173 Jul 78

To study differences in the distribution of proteoglycans and their relationships to collagen fibrils in the cornea and sclera, bovine cornea and sclera were examined histochemically using the ruthenium red (RR) staining method. RR-positive granules (30 nm in diameter) were present in association with fine filamentous materials (3 nm in diameter and 30-100 nm in length) in the interfascicular spaces of collagen bundles in both the corneal stroma and sclera. The amount of these materials was smaller in the sclera than in the cornea. The characteristic band-like arrangement of RR-positive granules connected by filamentous materials at intervals of 80-100 nm was found only in the cornea. In enzyme digestion experiments, tissue sections were treated by chondroitinase ABC, AC, and keratanase before RR staining. The RR-positive granules and their associated filamentous materials were darkly stained after chondroitinase AC or keratanase digestion, but displayed markedly lighter staining after chondroitinase ABC digestion. These results indicate that RR-positive granules and filamentous materials contain dermatan sulfate proteoglycan.
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PMID:Electron microscopic study of distribution of proteoglycans in bovine cornea and sclera. 177 92

Primary cultures of rat hepatocytes maintained as monolayer in a serum-free medium synthesise and secrete sulphated proteoglycans. Nearly 5% of the total 35(S)-sulphated material was obtained in a soluble form from beneath the cell layer. A shift in gel filtration pattern on beta-elimination with alkali suggested that it is a sulphated proteoglycan. On ion exchange chromatography over Dowex AG 1 x 2, the major fraction was eluted with 1.25 M NaCl. Further, nearly 80% of the 35(S)-labeled material was susceptible to nitrous acid degradation and more than 90% of the material was resistant to chondroitinase ABC digestion suggesting that it is predominantly a heparan sulphate proteoglycan (HSPG). Since HSPG is a major component of basement membrane, its binding with collagen was studied by a solid phase binding assay. About 75% of the 35(S) HSPG bound to wells coated with type IV collagen whereas only about 20% bound to type I collagen at physiological pH. Binding to collagen IV was reduced by about 50% when free GAG chains were used indicating that the protein core is also involved in interaction with the collagen. These results indicate the possible role of this basal extracellular heparan sulphate proteoglycan in the basal lamina formation.
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PMID:Isolation of heparan sulfate proteoglycan from beneath the monolayers of rat hepatocytes and its binding to type IV collagen. 187 99

After immunization with heparan sulfate proteoglycan (HSPG) isolated from human glomeruli, two mouse monoclonal antibodies (mAbs) against heparan sulfate (HS) were obtained. Both mAbs were of the IgM isotype and showed identical specificity. One of these, mAb JM-13 is described in detail. In enzyme-linked immunosorbent assay and Western blotting, reactivity was found with human glomerular basement membrane HSPG and HS. No binding occurred to the core protein of HSPG obtained after removal of HS with trifluoromethanesulfonic acid. In enzyme-linked immunosorbent assay, mAb JM-13 did neither bind to other proteoglycans, nor to other basement membrane components like collagen type IV, laminin, or fibronectin. In indirect immunofluorescence on cryostat sections of human kidneys, a restricted staining of tubular basement membranes was observed along with staining of the vascular basement membranes. In the glomerulus, a weak, fine granular staining was seen along the capillary wall and in the mesangium. MAb JM-13 bound also to the basolateral cell membranes of proximal tubular cells, to the cell membranes of cultured human and rat glomerular visceral epithelial cells, rat mesangial cells, human hepatocytes in culture, and in liver cryostat sections, indicating also a recognition of cell surface-associated HS. Pretreatment of the sections with heparitinase abolished binding of JM-13, whereas treatment with chondroitinase ABC had no effect. Inhibition studies in enzyme-linked immunosorbent assay as well as in indirect immunofluorescence corroborated the HS specificity of mAb JM-13. In conclusion, mAb JM-13 binds to an epitope on the HS chains of glomerular, tubular, and cell surface-associated HSPG.
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PMID:Production and characterization of a monoclonal antibody against human glomerular heparan sulfate. 189 Aug 9

Effect of aminonucleoside of puromycin (PAN) on metanephric development and proteoglycans (PGs) was investigated. Murine metanephric tissues, obtained on the thirteenth day of gestation, were exposed to PAN in a culture medium for one to seven days and processed for morphological, histochemical and immunofluorescent studies. For tissue autoradiographic and biochemical studies, kidneys were labelled with a precursor product of PGs, that is, [35S]-sulfate. A generalized decrease in the glomerular population along with swelling and deformation in the ureteric bud branches was observed. These changes were accompanied with a diminution in the total incorporated radioactivity and a reduction in the autoradiographic grains, especially over the tips of ureteric bud branches. Sepharose CL-4B chromatography revealed a major high molecular weight PG (Mr greater than 2.5 x 10(6], and a relative increase in the chondroitinase-ABC sensitive PGs. The media PGs were of relatively smaller size. Immunoprecipitation experiments with [35S]-methionine-labeled tissues and immunofluorescent studies revealed a significant decrease of PGs in metanephric tissues, while type IV collagen and laminin were relatively unaffected. Significant glomerular changes included failure in differentiation of the visceral epithelial foot processes, formation of villi and in maturation of glomerular basement membrane. The latter was seen as fragments of extracellular matrices interspersed among undifferentiated podocytes and had reduced staining with ruthenium red--a dye marker for the PGs. This deficiency of PGs was confirmed by electron microscopic autoradiography, where a reduction in the number of silver grains was observed. The fact that the PAN-induced cellular and extracellular alterations were associated with perturbances in biosynthesis of PGs, suggests that the morphogenetic regulators, that is, PGs play a vital role in various differentiation processes involved during metanephric development.
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PMID:Effect of puromycin on metanephric differentiation: morphological, autoradiographic and biochemical studies. 189 69

The biosynthesis of interstitial collagens (types I and III) and proteoglycans was studied in fibroblasts isolated from the parietal layer of bovine pericardium. Confluent cultures were labeled with Na2 35SO4 for proteoglycans or 14C-proline for collagens. The proteoglycans synthesized by pericardial fibroblasts were purified by DEAE-Sephacel chromatography and further fractionated into three components by gelfilitration. Two minor high molecular weight proteoglycans were shown by SDS-PAGE to be resistant to chondroitinase ABC and AC, and partially degraded by nitrous acid. The major, low molecular weight proteoglycan had a core protein of 45 kDa and is considered to be a dermatan sulfate/chondroitin sulfate proteoglycan since it was resistant to nitrous acid, but digested partially by chondroitinase AC and completely by ABC. The pericardial fibroblasts synthesized predominantly type I collagen and low amounts (about 10%) of type III collagen which was detected by delayed reduction on SDS-PAGE. The data show that pericardial fibroblasts synthesize the same macromolecules that can be extracted from the intact tissue and suggest that the proteoglycan may play a structural as well as physiological role.
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PMID:The biosynthesis of proteoglycans and interstitial collagens by bovine pericardial fibroblasts. 205 65


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