Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0272170 (SDS)
 50,377 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Collagen types in normal human and keratoconus corneas were separated by salt fractionation and thermal gelation in the pepsin-soluble fraction of the lyophilized tissues. Peptic digestion indicated no significant differences between normal and keratoconus corneas. Further collagen characterization was performed using SDS-PAGE. Collagen concentration were determined via hydroxyproline. Soluble collagens from normal human cornea represent 85% collagen type I, maximally 10% collagen type III and 5% collagen type V. Soluble collagens of keratoconus corneas consist of 90% type I collagen and maximally 5% type II and type V collagen.
 ...
PMID:Collagen types in keratoconus. 709 51

The differentiated phenotype of rabbit articular chondrocytes consists primarily of type II collagen and cartilage-specific proteoglycan. During serial monolayer culture this phenotype is lost and replaced by a complex collagen phenotype consisting predominately of type I collagen and a low level of proteoglycan synthesis. Such dedifferentiated chondrocytes reexpress the differentiated phenotype during suspension culture in firm gels of 0.5% low Tm agarose. Approximately 80% of the cells survive this transition from the flattened morphology of anchorage-dependent culture to the spherical morphology of anchorage-independent culture and then deposit characteristic proteoglycan matrix domains. The rates of proteoglycan and collagen synthesis return to those of primary chondrocytes. Using SDS-polyacrylamide gel electrophoresis of intact collagen chains and two-dimensional cyanogen bromide peptide mapping, we demonstrated a complete return to the differentiated collagen phenotype. These results emphasize the primary role of cell shape in the modulation of the chondrocyte phenotype and demonstrate a reversible system for the study of gene expression.
 ...
PMID:Dedifferentiated chondrocytes reexpress the differentiated collagen phenotype when cultured in agarose gels. 712 71

Left ventricular collagen of various mammals (cat, cow, dog, pig, and rat) was successively extracted with neutral salt, and dilute acid solutions, and limited pepsin digestion. The distribution of the various types of collagen molecules in pepsin-solubilized ventricular collagen was analyzed electrophoretically on SDS-polyacrylamide gels in the presence of 3.6 M urea. Yields of dilute-acid-soluble collagen were only 0.4 to 0.6% of the total ventricular collagen, and less than 0.1% with neutral salt solution. Approx. 55-90% of the total collagen was extracted by limited pepsin digestion. Disc patterns of pepsin-soluble collagen revealed the presence of dimeric and trimeric components, as well as higher-molecular-weight aggregates in all samples of nonreduced and reduced ventricular collagen. Taken together, these findings suggest the presence of an extensive interchain and intermolecular cross-linking network in left ventricular collagen. Comparison of electrophoretical disc gel patterns of reduced and nonreduced pepsin-solubilized collagen indicated that left ventricular collagen is heterogenous in nature, consisting of a mixture of type I and type III collagen. It was evident that primarily type I components occur in ventricular collagen. The components of type III collagen molecules occurred in all investigated left ventricles in varying and consistently appreciably lower amounts. The proportions of type III and type I collagen vary in left ventricular tissue of different species.
 ...
PMID:Characterization of intramuscular collagen in mammalian left ventricle. 715 57

Type I collagen was prepared from bovine renal cortices by pepsin digestion followed by differential salt fractionation, and was identified by SDS-polyacrylamide gel electrophoresis, CM-cellulose chromatography, and by the analysis of CNBr-cleavage products of the alpha 1 chain. About 61-87% of total collagen in the tissue was solubilized by this procedure and type I collagen represents about 40% of the collagen solubilized. Renal cortex type I collagen is characteristic in that the extent of hydroxylation of the prolyl residues is high, but that of the lysyl residues is at the same level as in skin. Tissue-specific differences in the hydroxylation of prolyl residues of type I collagen are also discussed.
 ...
PMID:Bovine renal cortex type I collagen: high contents of 3- and 4-hydroxyprolines. 727 45

Procollagen and collagen were isolated from the culture medium of normal bovine corneal stromal fibroblasts. DEAE-cellulose chromatography was used to separate the collagen molecules from the different procollagens present. One collagen and four procollagen peaks were isolated and biochemically characterized. All the procollagen fractions and the collagen fraction yielded, after limited pepsin or chymotrypsin digestion followed by CNBr digestion, molecules that correspond to (alpha 1)2 alpha 2 exclusively. Thus only type I collagen is found in the growth medium of of bovine corneal stromal fibroblast cultures. Each of the individual procollagen peaks contained pro-alpha chains having molecular weights of 120,000, 150,000, 165,000, 180,000, and 190,000 daltons, according to their elution position on DEAE-cellulose. The presence of type I procollagen molecules having pro-alpha chains of 165,000, 180,000, and 190,000 daltons has not previously been reported and probably represents higher-molecular-weight precursor intermediates. The amino acid compositions of the different procollagen fractions are unique, and each contains relatively large amounts of cysteine and tryptophan. Carbohydrate analysis, cyanogen bromide peptide analysis, electron microscopy of SLS-crystallities, and SDS-polyacrylamide gel electrophoresis were used to further characterize the procollagen and collagen molecules.
 ...
PMID:Procollagen and collagen produced by normal bovine corneal stroma fibroblasts in cell culture. 735 53

A trypsin-like protease was purified from spent culture medium of oral pathogen Porphyromonas gingivalis by chromatography on columns of DEAE-Sepharose, gel filtration on Sephadex G-100, and chromatofocusing on PBE-94. Purified enzyme showed a single band on SDS-polyacrylamide gel electrophoresis with an estimated molecular weight of 55,000. Purified protease hydrolyzed type I, III, IV, and V collagen from human placenta, and type I collagen from rat tail and calf skin, but did not hydrolyze type II collagen from chicken sternal cartilage. The purified enzyme also hydrolyzed the C3 component of complement, fibrinogen, fibronectin, alpha 1-antitrypsin, alpha 2-macroglobulin, apotransferrin, and human serum albumin. The hydrolytic activity of the purified enzyme on chromogenic substrates was limited to substrates with arginine in the P-1 position, although synthetic peptides were also cleaved at Lys-X linkage. The enzyme was activated by reducing agents dithiothreitol, L-cysteine, and glutathione and inhibited by cysteine protease inhibitors N-ethylmaleimide, iodoacetic acid, and iodoacetamide. The enzyme was also inhibited by trans-epoxysuccinyl-L-leucylamido(4-guanidino)butane (E-64), leupeptin, antipain, salivary histidine-rich protein (HRP-5), soybean trypsin inhibitor, and EDTA. Since the protease is able to degrade the connective tissue components of periodontal tissue as well as components of host defense mechanism, this enzyme may be a potent virulence factor of P. gingivalis involved in invasion and tissue destruction.
 ...
PMID:Purification and characterization of a collagen-degrading protease from Porphyromonas gingivalis. 750 59

We have previously shown that SV40 large T oncogene is able to induce mouse chondrocyte proliferation without loss of expression of types II, IX, and XI collagen, as well as cartilage aggrecan and link protein. The cell line obtained (termed MC 615) also expressed some type I collagen in monolayer and we have investigated if anchorage-independent conditions could inhibit type I collagen synthesis and promote hypertrophy and type X collagen synthesis. The MC 615 cells were grown in agarose in the presence of serum, and GAG accumulation, DNA content, and matrix synthesis rates were monitored after incubation with [35S]sulfate and [3H]- or [14C]proline. SDS-PAGE analysis of pepsin-extracted samples showed that type I collagen was still synthesized by the MC 615 cells, from the beginning of the culture and at low or high density. Type II collagen synthesis was demonstrated by immunoblotting, but type X collagen synthesis was not detected, indicating that the MC 615 chondrocytes immortalized by large T were still blocked in their maturation pathway. The cells were also grown over agarose and electron microscopy (E. M.) analysis of the cell aggregates showed an extracellular matrix rich in proteoglycans and in type II-containing collagen fibrils. To gain insight into the role of type IX collagen in cartilage collagen assembly and/or matrix organization, we also immortalized embryonic chondrocytes isolated from mice lacking alpha 1 (IX) collagen and obtained a clone termed 4KO 91. As found for the MC 615 cells, the 4KO 91 cells synthesized type II collagen as demonstrated by Western blotting and some type I collagen identified by the presence of alpha 2(I) chains after electrophoretic analysis of pepsin-digested collagen chains. E. M. analysis of the extracellular matrices synthesized by the two cell lines revealed differences in collagen structure and organization. In the absence of alpha 1 (IX) collagen chains, the collagen fibrils seemed to fuse laterally, suggesting that collagen IX acts as a "spacer" between fibrils, to keep them apart.
 ...
PMID:Analysis of collagen synthesis and assembly in culture by immortalized mouse chondrocytes in the presence or absence of alpha 1(IX) collagen chains. 762 41

1. Skin fibroblast lines were cultured from nine patients who had the features of idiopathic juvenile osteoporosis, six relatives, five unrelated control subjects and three unrelated patients with osteogenesis imperfecta type I. Some patients with idiopathic juvenile osteoporosis were adults whose previous osteoporosis was in remission. Two patients with idiopathic juvenile osteoporosis were siblings and one patient with idiopathic juvenile osteoporosis had a daughter with severe osteogenesis imperfecta (type III). 2. The ratio of type III to type I collagen, synthesized by fibroblasts, was increased in two of the patients with osteogenesis imperfecta type I and in the daughter with osteogenesis imperfecta type III, but was normal in all the other patients with idiopathic juvenile osteoporosis and the other relatives. 3. Radiolabelled collagen was digested by cyanogen bromide and separated on SDS-PAGE. Unreduced collagen peptides migrated normally, except those from both the two siblings with idiopathic juvenile osteoporosis. In these two lines, abnormal migration suggested the presence of collagen I mutations. 4. The secretion of synthesized collagen by these two idiopathic juvenile osteoporosis lines and two others was reduced to only 43-45% as compared with a line from a 13-year-old control subject, which was defined as 100%. The three osteogenesis imperfecta type I lines secreted 18-37%, the other five idiopathic juvenile osteoporosis lines secreted 57-75%, the relatives (including the daughter with severe osteogenesis imperfecta) secreted 49-115% and the controls secreted 69-102%.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Type I collagen biosynthesis by skin fibroblasts from patients with idiopathic juvenile osteoporosis. 767 70

In murine mastocytoma P815, gene P1A directs the expression of antigens P815A and B which are the target of a T cell-mediated rejection response in syngeneic animals. This gene is expressed at a high level in various tumors, but is silent in normal tissues except testis and placenta; its activation is thus possibly related to malignant transformation. An anti-synthetic peptide rabbit antiserum reacted by immunoblotting with a cellular protein migrating near 40 kDa on SDS-PAGE. The immunoreactive protein was detected only in lysates from cells which express antigen P815A: P1.HTR mastocytoma cells and, after transfection with cosmids carrying the P1A gene, the antigen-loss variant P0.HTR cells and DAP-3 H-2Ld fibroblasts. The identity of this protein as the P1A gene product was confirmed by cell-free transcription-translation of the P1A cDNA, the product of which also migrated near 40 kDa in SDS-PAGE and was captured by protein A-Sepharose in the presence of the antiserum. Subcellular fractionation by differential and isopycnic centrifugation indicated that the P1A protein is associated with cytoplasmic membranes demonstrating a broad distribution with respect to size and density. Immunofluorescence microscopy also revealed a cytoplasmic signal, particularly intense in small vesicles, which coincides with that produced by an anti-mouse type I collagen guinea pig antiserum except near the cell periphery where the P1A signal is weaker. We conclude that the P1A protein is bound to membranes of the secretory pathway, at a concentration which goes increasing from the endoplasmic reticulum to secretion vesicles.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Identification and characterization of the tumor-specific P1A gene product. 769 73

The effect of 0.1-10 microM retinoic acid (RA) on foetal bovine chondrocytes was investigated in high-density cultures (0.6 x 10(6) cells/cm2). After 5 days of culture in ascorbate-free medium, control chondrocytes presented a typical rounded shape and synthesized type II, IX, XI and III collagens. After RA treatment on days 2-5 of culture, the cells exhibited a fibroblast-like shape and decreased synthesis of total protein (48%) and pepsinresistant proteins (60%) as determined by [35S]methionine labelling. Addition of RA was not followed by the expression of type I collagen, but induced quantitative changes in the synthesis of cartilage-specific collagens (II, IX and XI) as measured by direct autoradiography of the corresponding bands after SDS/PAGE. The main change was in type II collagen synthesis, with a 80% decrease in the cell-layer fraction and a 89% decrease in culture-medium fraction; inhibition of type IX and XI collagen synthesis was limited to 25 and 31% respectively. Modifications to intracellular proteins induced by RA were determined by using two-dimensional electrophoresis associated with a computerized imaging system. Synthesis of one of the more abundant proteins (pI 4.8; 78 kDa) was decreased by 75% after RA treatment. This protein was characterized by micro-sequencing as the glucose-regulated protein 78 (GRP 78). It was reported previously to bind denatured collagen and mutated type I procollagen molecule and to function as a molecular chaperone for collagen molecules. It remains to demonstrate whether the parallel down-regulation of GRP 78 and type II collagen observed here corresponds to a co-ordinate regulation of these two proteins.
 ...
PMID:Effect of retinoic acid on protein synthesis by foetal bovine chondrocytes in high-density culture: down-regulation of the glucose-regulated protein, GRP-78, and type II collagen. 783 51


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>