Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:4.2.2.7 (heparinase)
 1,270 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Glycosaminoglycans have been demonstrated throughout the cutaneous BMZ at the ultrastructural level. Colloidal iron and cationised ferritin proved of limited value, whilst staining with Alcian blue and application of the critical electrolyte concentration principle has provided evidence for the presence of sulphated GAGs at the lamina lucida and lamina reticularis. Digestions with chondroitin ABC lyase and heparin lyase have confirmed the existence of chondroitin and/or dermatan sulphates and heparan sulphates, although the results obtained with hyaluronate lyase have indicated that hyaluronates are also present.
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PMID:Ultrastructural localisation of anionic sites at the dermo-epidermal junction in normal human skin. 171 20

The high-iron diamine staining (HID), which has been used in histochemistry to stain sulfated glycoconjugates (SGC), was tested for detectability of authentic acidic substances (chondroitin sulfates A plus C, dermatan sulfate, heparan sulfate, chondroitin, hyaluronic acid, alpha 1-acid glycoprotein and ribonucleic acid) in electrophoresis on cellulose acetate membrane (Separax). The results showed that only SGC were detectable by the HID, although all the above substances were stained with alcian blue. The glycoconjugate preparations obtained from the liver, kidney, lung, small intestine, colon, stomach, brain and spleen of rats were examined by two-dimensional electrophoresis on Separax. The new spots (or bands), besides those of sulfated glycosaminoglycans, were detected by the HID on the electrophoretograms of all the samples except for the kidney one. The substances giving the new spots (or bands) were indicated to be sulfated glycopeptides (SGP) by crude heparinase digestion of a representative sample. The present results revealed that the HID was applicable for detection of SGP in electrophoresis on cellulose acetate membrane. Also, it is a novel finding that the liver and spleen contain SGP.
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PMID:An application of the high-iron diamine staining for detection of sulfated glycoproteins (glycopeptides) in electrophoresis on cellulose acetate membrane. 240 56

Sulfated glycoconjugates were ultrastructurally localized within embryonic chick marrow by using the high iron diamine-silver proteinate stain. Stain was concentrated in the extravascular, granulopoietic compartment, indicating that granulopoiesis, but not erythropoiesis, proceeded in a highly sulfated environment. It was likely that most of the stainable material represented sulfated proteoglycans since staining was abrogated by predigesting tissue with enzymes and other treatments known to degrade specific glycosaminoglycan chains. Chondroitinase/hyaluronidase digestion resulted in the removal of most of the stainable material associated with the extracellular matrix and a portion of the stainable material associated with fibroblastic cell surfaces. Unaffected material lay in close proximity to fibroblastic cell membranes. Heparitinase/heparinase digestion had essentially the opposite effect. Sulfated material associated with matrix components was largely unaffected, but the fibroblastic plasmalemmal material was now absent. These results suggest that there are at least two categories of sulfated proteoglycans in the granulopoietic compartment, each differentially distributed. The plasmalemmal material likely represented heparan sulfate which in this tissue appeared to be associated in a uniform layer with fibroblastic stromal cell membranes and not with blood or endothelial cell membranes. Material identified as chondroitin sulfates was found within patches of amorphous matrix that was located on fibroblastic stromal cell surfaces and that was interspersed with fibrils in the extracellular matrix. Chondroitin sulfates were sparsely distributed on granulocytic cell surfaces.
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PMID:Ultrastructural localization of heparan sulfate and chondroitin sulfates associated with granulopoiesis in embryonic chick bone marrow. 244 89

Glomerular development was studied in the newborn rat kidney by electron microscopy and cytochemistry. Glomerular structure at different developmental stages was related to the permeability properties of its components and to the differentiation of anionic sites in the glomerular basement membrane (GBM) and on endothelial and epithelia cell surfaces. Cationic probes (cationized ferritin, ruthenium red, colloidal iron) were used to determine the time of appearance and distribution of anionic sites, and digestion with specific enzymes (neuraminidase, heparinase, chondroitinases, hyaluronidases) was used to determine their nature. Native (anionic) ferritin was used to investigate glomerular permeability. The main findings were: (a) The first endothelial fenestrae (which appear before the GBM is fully assembled) possess transient, negatively charged diaphragms that bind cationized ferritin and are impermeable to native ferritin. (b). Two types of glycosaminoglycan particles can be identified by staining with ruthenium red. Large (30-nm) granules are seen only in the cleft of the S-shaped body at the time of mesenchymal migration into the renal vesicle. They consist of hyaluronic acid and possibly also chondroitin sulfate. Smaller (10-15-nm) particles are seen in the earliest endothelial and epithelial basement membranes (S-shaped body stage), become concentrated in the laminae rarae after fusion of these two membranes to form the GBM, and contain heparan sulfate. They are assumed to be precursors of the heparan sulfate-rich granules present in the mature GBM. (c) Distinctive sialic acid-rich, and sialic acid-poor plasmalemmal domains have been delineated on both the epithelial and endothelial cell surfaces. (d) The appearance of sialoglycoproteins on the epithelial cell surface concides with the development of foot processes and filtration slits. (e) Initially the GBM is loosely organized and quite permeable to native ferritin ;it becomes increasinly impermeable to ferritin as the lamina densa becomes more compact. (f) The number of endothelial fenestrae and open epithelial slits increases as the GBM matures and becomes organized into an effective barrier to the passage of native ferritin.
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PMID:Assembly of the glomerular filtration surface. Differentiation of anionic sites in glomerular capillaries of newborn rat kidney. 615 76

The location and chemical composition of anionic sites in Bruch's membrane (BM) were examined using cationic probe molecules demonstrable in electron microscopic preparations and tissue digestion with specific degradative enzymes. Ruthenium red and native lysozyme revealed densities distributed at regular intervals in two major components of BM: the basal laminae of the retinal pigment epithelium (RPE) and choriocapillary endothelium (EN). Staining was not observed with succinylated lysozyme (anionic). Colloidal iron also failed to stain BM components. Following crude heparinase treatment at 43 degrees C (specific for heparan sulfate) anionic sites in the RPE basal lamina were not demonstrable with either ruthenium red or native lysozyme. Sites in the EN basal lamina were not affected. Chondroitinase treatment removed almost all of the ruthenium red-positive material in the EN basal lamina; lysozyme binding here was markedly reduced. No changes were observed in the RPE basal lamina after chondroitinase digestion. There was no morphological evidence for site removal by either neuraminidase or leech hyaluronidase, although a detachment of the RPE from BM often occurred after incubation of eye tissue in the latter. Pronase E removed all stainable material. These findings indicate that anionic sites in BM consist to a large extent of chondroitin sulfates and heparan sulfate.
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PMID:Location and chemical composition of anionic sites in Bruch's membrane of the rat. 617 64

We have compared the ability of lactoferrin and transferrin to interact with and donate iron to the monocytic cell line U937. About 10 times more lactoferrin was bound than transferrin, but most lactoferrin bound nonspecifically, and the degree of specific binding was similar for both proteins (2-3 x 10(6) sites/cell). The binding affinity for lactoferrin (83 nM) was about 4-fold lower than for transferrin (21 nM). Lactoferrin did not inhibit binding of transferrin, or vice versa. Binding of lactoferrin was not inhibited by 30 mM glucose or fucose nor by incubating the cells with heparinase. Transferrin, but not lactoferrin, was internalized, and 3 mM primaquine caused intracellular accumulation of transferrin but not lactoferrin. The cells rapidly acquired iron from transferrin, but uptake from lactoferrin was 10-fold slower and probably resulted from transfer of 59Fe from lactoferrin to unlabeled transferrin during culture. Lactoferrin, but not transferrin, released iron to the extracellular medium when bound to U937 cells. Lactoferrin inhibited cellular uptake of iron from Fe-nitrilotriacetate but not from transferrin. It is concluded that transferrin, but not lactoferrin, acts as an iron donor to U937 cells. Lactoferrin may regulate uptake of potentially toxic non-transferrin-bound iron.
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PMID:Binding of lactoferrin and transferrin to the human promonocytic cell line U937. Effect on iron uptake and release. 840 13

Types and distribution patterns of glycoconjugates in antral ovarian follicles were investigated in the buffalo, using periodic-acid Schiff (PAS), high iron diamine (HID), low ion diamine (LID) and lectin histochemical staining methods. HID and LID staining procedures were preceded in some cases by digestion with testicular hyaluronidase, Streptomyces hyaluronidase, chondroitinase ABC and heparitinase (heparinase III). Lectin staining was performed with the use of 12 horseradish peroxidase (HRP) lectin conjugates. Some lectin staining procedures were preceded by neuraminidase digestion and saponification. Large amounts of isomeric chondroitin sulphates and a minor quantity of heparan sulphate and hyaluronic acid and/or chondroitin were found in follicular fluid. Lectin staining of buffalo follicular fluid revealed glycoconjugates with different glucidic determinants such as beta-N-acetylgalactosamine, beta-galactose-(1-3)-N-acetylgalactosamine, beta-galactose-(1-4)-N-acetylglucosamine, N-acetylglucosamine, alpha-fucose and alpha-glucose/alpha-mannose, and sialic acid residues. Glycosaminoglycans were absent in the zona pellucida of oocytes in small antral follicles. Acidic glycoconjugates in the zona pellucida were caused by sulphated groups and sialic acid residues. Our data show few internal glucidic residues, such as N-acetylglucosamine in the buffalo zona pellucida but many subterminal beta-N-acetylgalactosamine, alpha- and beta-galactose determinants masked by sialic acids. These findings demonstrate that buffalo follicular fluid has a very heterogeneous composition that is similar to that found in small and large bovine follicles. No differences in composition of the follicular fluid were observed in the follicles examined.
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PMID:Glycoconjugates in small antral ovarian follicles of the river buffalo (Bubalus bubalis L.). 971 61

Bovine lactoferrin (bLf) is an iron-binding secretory protein present in breast milk, mucosal secretions, and the secondary granules of neutrophils. Although bLf has multiple functions, including antimicrobial and immunomodulatory activities, its effect on neuronal cells is not fully understood. We report that bLf prevents cell adhesion of PC12 cells and allows them to be cultivated in suspension. PC12 cells normally adhere well to plastic culture plates and show anchorage-dependent cell growth, but we found that soon after adding bLf, they detach from culture plates and begin to grow in suspension. When bLf was removed from the medium, the cells began to re-adhere to the plates. Thus, bLf inhibits cell adhesion and stimulates anchorage-independent growth in PC12 cells. On the other hand, bLf-induced cell suspension growth was not observed when cells were grown on a laminin matrix, suggesting that bLf does not affect integrin-mediated cell adhesion on a laminin matrix. Treatment of cells with heparin or chondroitin sulfate A or C inhibited bLf-induced growth in cell suspension. Furthermore, pretreatment of cells with heparinase and/or chondroitinase prevented direct binding of bLf to the cell membrane. These results suggest that bLf binds to the membrane of PC12 cells via membrane-associated proteoglycans and leads to anchorage-independent growth.
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PMID:Bovine lactoferrin stimulates anchorage-independent cell growth via membrane-associated chondroitin sulfate and heparan sulfate proteoglycans in PC12 cells. 1767 95