scholarly journals Dermatan sulphate proteoglycans from sclera examined by rotary shadowing and electron microscopy

1987 ◽  
Vol 242 (3) ◽  
pp. 761-766 ◽  
Author(s):  
N P Ward ◽  
J E Scott ◽  
L Cöster
Keyword(s):  
Electron Microscopy ◽  
Chondroitin Sulphate ◽  
Side Chains ◽  
Dermatan Sulphate ◽  
Sulphate Proteoglycan ◽  
Cartilage Proteoglycan ◽  
Chondroitin Sulphate Proteoglycan ◽  
Proteoglycan Aggregates ◽  
Rotary Shadowing

Two dermatan sulphate-containing proteoglycans from bovine sclera were examined by rotary shadowing and electron microscopy, and the results were compared with previous biochemical findings. Both the large iduronate-poor proteoglycan (PGI) and the small iduronate-rich proteoglycan (PGII) possessed a globular proteinaceous region. Whereas PGI had a branched extension from the globular region, with five to eight side chains attached to it, PGII had only a single tail, which was of glycosaminoglycuronan. PGII aggregated via globular-region interactions, which were much diminished by reduction and alkylation. PGI aggregated via side chains and globular-region interactions. Although a few PGI aggregates were large, and similar to the hyaluronan-cartilage proteoglycan aggregates [Weidemann, Paulsson, Timpl, Engel & Heinegård (1984) Biochem. J. 224, 331-333], hyaluronan did not cause enhanced aggregation. PGII is very similar in shape to the small cartilage chondroitin sulphate proteoglycan, whereas PGI somewhat resembles the large cartilage chondroitin sulphate proteoglycan, although with many fewer glycosaminoglycan side chains, and probably only one globular region as opposed to two in the cartilage proteoglycan.

Proteoglycan-collagen interactions in intervertebral disc. A chondroitin sulphate proteoglycan associates with collagen fibrils in rabbit annulus fibrosus at the d-e bands

1986 ◽  
Vol 6 (10) ◽  
pp. 879-888 ◽  
Author(s):  
J. E. Scott ◽  
M. Haigh
Keyword(s):  
Electron Microscopy ◽  
Intervertebral Disc ◽  
Annulus Fibrosus ◽  
Electrolyte Concentration ◽  
Chondroitin Sulphate ◽  
Collagen Fibrils ◽  
Dermatan Sulphate ◽  
Keratan Sulphate ◽  
Sulphate Proteoglycan ◽  
Chondroitin Sulphate Proteoglycan

Rabbit annulus fibrosus and nucleus pulposus were analysed for hydroxyproline, chondroitin sulphate, keratan sulphate and dermatan sulphate. Tissue proteoglycans were stained for electron microscopy with Cupromeronic blue, used in the critical electrolyte concentration mode, with and without prior digestion by chondroitinase AC or ABC, hyaluronidase or keratanase. Collagen bands, a—e were demonstrated with UO2++. A chondroitin sulphate proteoglycan was found orthogonally associated with loosely packed collagen fibrils in annulus fibrosus at the d and e bands. The close metabolic and structural analogies with the dermatan sulphate proteoglycans previously shown to be located at collagen d-e bands in tendon, skin, etc. (Scott and Haigh (1985) Biosci. Rep.5:71–81), are discussed. Tightly packed annulus collagen fibrils were surrounded by axially oriented proteoglycan filaments, mostly without specific locations.

scholarly journals Cartilage proteoglycan aggregates. Electronmicroscopic studies of native and fragmented molecules

1978 ◽  
Vol 175 (3) ◽  
pp. 913-919 ◽  
Author(s):  
Dick Heinegård ◽  
Stefan Lohmander ◽  
Johan Thyberg
Keyword(s):  
Electron Microscopy ◽  
Hyaluronic Acid ◽  
Electron Micrographs ◽  
Chondroitin Sulphate ◽  
Average Length ◽  
Side Chain ◽  
Nasal Cartilage ◽  
Cartilage Proteoglycan ◽  
Central Filament ◽  
Proteoglycan Aggregates

1. Proteoglycan aggregates from bovine nasal cartilage were studied by using electron microscopy of proteoglycan/cytochrome c monolayers. 2. The aggregates contained a variably long central filament of hyaluronic acid with an average length of 1037nm. The proteoglycan monomers attached to the hyaluronic acid appeared as side chain filaments varying in length (averaging 249nm). They were distributed along the central filament at an average distance of about 36nm. 3. Chondroitin sulphate side chains were removed from the proteoglycan monomers of the aggregates by partial chondroitinase digestion. The molecules obtained had the same general appearance as intact aggregates. 4. Proteoglycan aggregates were treated with trypsin and the largest fragment, which contains the hyaluronic acid, link protein and hyaluronic acid-binding region, was recovered and studied with electron microscopy. Filaments that lacked the side chain extensions and had the same length as the central filament in the intact aggregate were observed. 5. Hyaluronic acid isolated after papain digestion of cartilage extracts gave filaments with similar length and size distribution as observed for the central filament both in the intact aggregate and in the trypsin digests. 6. Umbilical-cord hyaluronic acid was also studied and gave electron micrographs similar to those described for hyaluronic acid from cartilage. However, the length of the filament was somewhat shorter. 7. The electron micrographs of both intact and selectively degraded proteoglycans corroborate the current model of cartilage proteoglycan structure.

scholarly journals Chondroitin Sulphate Proteoglycan 4 (NG2/CSPG4) Localization in Low- and High-Grade Gliomas

Cells ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 1538 ◽  
Author(s):  
Marta Mellai ◽  
Laura Annovazzi ◽  
Ilaria Bisogno ◽  
Cristiano Corona ◽  
Paola Crociara ◽  
...  
Keyword(s):  
Cell Transformation ◽  
Chondroitin Sulphate ◽  
Molecular Genetic ◽  
Malignant Gliomas ◽  
Malignant Cell ◽  
Wild Type ◽  
Sulphate Proteoglycan ◽  
Chondroitin Sulphate Proteoglycan ◽  
Proteoglycan 4

Background: Neuron glial antigen 2 or chondroitin sulphate proteoglycan 4 (NG2/CSPG4) is expressed by immature precursors/progenitor cells and is possibly involved in malignant cell transformation. The aim of this study was to investigate its role on the progression and survival of sixty-one adult gliomas and nine glioblastoma (GB)-derived cell lines. Methods: NG2/CSPG4 protein expression was assessed by immunohistochemistry and immunofluorescence. Genetic and epigenetic alterations were detected by molecular genetic techniques. Results: NG2/CSPG4 was frequently expressed in IDH-mutant/1p19q-codel oligodendrogliomas (59.1%) and IDH-wild type GBs (40%) and rarely expressed in IDH-mutant or IDH-wild type astrocytomas (14.3%). Besides tumor cells, NG2/CSPG4 immunoreactivity was found in the cytoplasm and/or cell membranes of reactive astrocytes and vascular pericytes/endothelial cells. In GB-derived neurospheres, it was variably detected according to the number of passages of the in vitro culture. In GB-derived adherent cells, a diffuse positivity was found in most cells. NG2/CSPG4 expression was significantly associated with EGFR gene amplification (p = 0.0005) and poor prognosis (p = 0.016) in astrocytic tumors. Conclusion: The immunoreactivity of NG2/CSPG4 provides information on the timing of the neoplastic transformation and could have prognostic and therapeutic relevance as a promising tumor-associated antigen for antibody-based immunotherapy in patients with malignant gliomas.

scholarly journals Chondroitin sulphate proteoglycan in the substratum adhesion sites of Balb/c 3T3 cells. Fractionation on various ion-exchange and affinity columns

1986 ◽  
Vol 235 (2) ◽  
pp. 469-479 ◽  
Author(s):  
B C Wightman ◽  
E A Weltman ◽  
L A Culp
Keyword(s):  
Extracellular Matrix ◽  
Affinity Chromatography ◽  
Chondroitin Sulphate ◽  
Heparan Sulphate ◽  
Heparan Sulphate Proteoglycan ◽  
3T3 Cells ◽  
Platelet Factor ◽  
Sulphate Proteoglycan ◽  
Adhesion Sites ◽  
Chondroitin Sulphate Proteoglycan

Proteoglycans on the cell surface play critical roles in the adhesion of fibroblasts to a fibronectin-containing extracellular matrix, including the model mouse cell line Balb/c 3T3. In order to evaluate the biochemistry of these processes, long-term [35S]sulphate-labelled proteoglycans were extracted quantitatively from the adhesion sites of 3T3 cells, after their EGTA-mediated detachment from the substratum, by using an extractant containing 1% octyl glucoside, 1 M-NaCl and 0.5 M-guanidinium chloride (GdnHCl) in buffer with many proteinase inhibitors. Greater than 90% of the material was identified as a large chondroitin sulphate proteoglycan (Kav. = 0.4 on a Sepharose CL2B column), and the remainder was identified as a smaller heparan sulphate proteoglycan; only small amounts of free chains of glycosaminoglycan were observed in these sites. These extracts were fractionated on DEAE-Sepharose columns under two different sets of elution conditions: with acetate buffer (termed DEAE-I) or with acetate buffer supplemented with 8 M-urea (termed DEAE-II). Under DEAE-I conditions about one-half of the material was eluted as a single peak and the remainder required 4 M-GdnHCl in order to recover it from the column; in contrast, greater than 90% of the material was eluted as a single peak from DEAE-II columns. Comparison of the elution of [35S]sulphate-labelled proteoglycan with that of 3H-labelled proteins from these two columns, as well as mixing experiments, indicated that the GdnHCl-sensitive proteoglycans were trapped at the top of columns, partially as a consequence of their association with proteins in these adhesion-site extracts. Affinity chromatography of these proteoglycans on columns of either immobilized platelet factor 4 or immobilized plasma fibronectin revealed that most of the chondroitin sulphate proteoglycan and the heparan sulphate proteoglycan bound to platelet factor 4 but that only the heparan sulphate proteoglycan bound to fibronectin, providing a ready means of separating the two proteoglycan classes. Affinity chromatography on octyl-Sepharose columns to test for hydrophobic domains in their core proteins demonstrated that a high proportion of the heparan sulphate proteoglycan but none of the chondroitin sulphate proteoglycan bound to the hydrophobic matrix. These results are discussed in light of the possible functional importance of the chondroitin sulphate proteoglycan in the detachment of cells from extracellular matrix and in light of previous affinity fractionations of proteoglycans from the substratum-adhesion sites of simian-virus-40-transformed 3T3 cells.

scholarly journals A study of the interaction in vitro between type I collagen and a small dermatan sulphate proteoglycan

1988 ◽  
Vol 251 (3) ◽  
pp. 643-648 ◽  
Author(s):  
N Uldbjerg ◽  
C C Danielsen
Keyword(s):  
Steady State ◽  
Binding Sites ◽  
Type I Collagen ◽  
Enzyme Linked Immunosorbent Assay ◽  
Side Chains ◽  
Type I ◽  
Dermatan Sulphate ◽  
Collagen Fibrillogenesis ◽  
High Affinity ◽  
Sulphate Proteoglycan

The interaction between a small dermatan sulphate proteoglycan isolated from human uterine cervix and collagen type I from human and rat skin was investigated by collagen-fibrillogenesis experiments. Collagen fibrillogenesis was initiated by elevation of temperature and pH after addition of proteoglycan, chondroitinase-digested proteoglycan or isolated side chains, and monitored by turbidimetry. Collagen-associated and unbound proteoglycan was determined by enzyme-linked immunosorbent assay after aggregation was complete. (1) The binding of proteoglycan to collagen could be explained by the presence of two mutually non-interacting binding sites, with Ka1 = 1.3 x 10(8) M-1 and Ka2 = 1.3 x 10(6) M-1. The number of binding sites per tropocollagen molecule was n1 = 0.11 and n2 = 1.1. The 0.1 high-affinity binding site per tropocollagen molecule indicates that the strong interaction between proteoglycan and collagen results from a concerted action of tropocollagen molecules in fibrils. Digestion of the proteoglycan with chondroitinase ABC did not affect these binding characteristics. (2) Proteoglycan did not affect the rate of fibrillogenesis, but increased the steady-state A400 by up to 90%. This increase was directly proportional to the saturation of the high-affinity type of binding sites. Neither isolated core protein nor isolated side chains induced a similar high increase in steady-state A400. (3) Electron micrographs showed that the fibril diameter was affected only to a minor extent, if at all, by the proteoglycan, whereas bundles of laterally aligned fibrils were common in the presence of proteoglycan. (4) Results obtained with human and rat collagen were similar.

Immunohistochemical Localization of Large Chondroitin Sulphate Proteoglycan in Porcine Gingival Epithelia

2001 ◽  
Vol 39 (2) ◽  
pp. 99-104 ◽  
Author(s):  
Yoshihiro Abiko ◽  
Michiko Nishimura ◽  
Firoz Rahemtulla ◽  
Itaru Mizoguchi ◽  
Tohru Kaku
Keyword(s):  
Chondroitin Sulphate ◽  
Immunohistochemical Localization ◽  
Sulphate Proteoglycan ◽  
Chondroitin Sulphate Proteoglycan

scholarly journals A chondroitin sulphate proteoglycan from human cultured glial and glioma cells. Structural and functional properties

1984 ◽  
Vol 221 (3) ◽  
pp. 845-853 ◽  
Author(s):  
B Norling ◽  
B Glimelius ◽  
A Wasteson
Keyword(s):  
Hyaluronic Acid ◽  
Chondroitin Sulphate ◽  
Buoyant Density ◽  
Glioma Cells ◽  
Keratan Sulphate ◽  
Link Protein ◽  
Sulphate Proteoglycan ◽  
Chondroitin Sulphate Proteoglycan ◽  
Chondroitin Sulphate Proteoglycans ◽  
Structural And Functional Properties

A chondroitin sulphate proteoglycan capable of forming large aggregates with hyaluronic acid was identified in cultures of human glial and glioma cells. The glial- cell- and glioma-cell-derived products were mutually indistinguishable and had some basic properties in common with the analogous chondroitin sulphate proteoglycan of cartilage: hydrodynamic size, dependence on a minimal size of hyaluronic acid for recognition, stabilization of aggregates by link protein, and precipitability with antibodies raised against bovine cartilage chondroitin sulphate proteoglycan. However, they differed in some aspects: lower buoyant density, larger, but fewer, chondroitin sulphate side chains, presence of iduronic acid-containing repeating units, and absence (less than 1%) of keratan sulphate. Apparently the major difference between glial/glioma and cartilage chondroitin sulphate proteoglycans relates to the glycan rather than to the protein moiety of the molecule.

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