Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.21.4 (trypsin)
42,187 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Skin fibroblasts from a patient with a lethal form of osteogenesis imprefecta were found to synthesize equal amounts of normal pro-alpha 1(I) chains and pro-alpha 1(I) chains which are about 10% shorter because of a deletion of about 100 amino acids in the middle of the alpha chain domain. The pro-alpha 1(I) chains were incorporated into three different kinds of trimers: a normal type I trimer with normal length pro-alpha 1(I) chains; a type Is trimer with one shortened pro-alpha 1(I) chain and two normal length chains; and a type Iss trimer containing two shortened pro-alpha 1(I) chains and one normal length pro-alpha 2(I) chain. As judged by resistance to digestion by chymotrypsin and trypsin, the type Is and Iss trimers denatured at a temperature at least 3 degrees C lower than normal type I procollagen. Procollagen containing the shortened pro-alpha 1(I) chains was slowly secreted by the cells but was degraded by extracellular proteinases within 6 h of chase into the medium. The results indicated that the presence of the shortened pro-alpha 1(I) chains in procollagen trimers produces a delay in rate of helix formation, overmodification of the polypeptides by post-translational enzymes, a decrease in the thermal stability of the trimers, and increased susceptibility of the protein to endogenous proteinases. Additionally, the fibroblasts of this patient synthesized and secreted a type III-like species of procollagen with unusual chromatographic properties.
...
PMID:Synthesis and processing of a type I procollagen containing shortened pro-alpha 1(I) chains by fibroblasts from a patient with osteogenesis imperfecta. 630

A highly unusual collagen was secreted by fibroblasts cultured from 150- and 270-d-old fetal calf nuchal ligaments. Purification revealed that this protein (which may be synthesized in a higher molecular weight form) was precipitated at unusually high concentrations of ammonium sulfate and was also eluted from DEAE-cellulose at greater salt concentrations than were types I and III procollagens. On SDS PAGE, the collagenous protein exhibited an Mr of approximately 12,750 that was not altered in the presence of reducing agent. The low molecular weight collagen (FCL-1) was sensitive to bacterial collagenase and had a [3H]glycine content comparable to that found in type I procollagen, although the [3H]Hyp to [3H]Pro ratio was 0.43. FCL-1 was not cleaved by human skin collagenase, mast cell protease, trypsin, Staphylococcal V8 protease, or proteinase K at 37 degrees C. The collagen was susceptible to trypsin, but not to V8 protease, only after heating at 80 degrees C for 30 min. Preliminary structural studies indicate that FCL-1 was resistant to cleavage by CNBr but exhibited limited proteolysis with pepsin. Both 150- and 270-d-old fibroblasts produced comparable levels of interstitial (types I and III) procollagens, which comprised approximately 70% of the total protein secreted into the culture medium. However, 270-d-old (term) fibroblasts secreted approximately 50% more FCL-1, as percent of total culture medium protein, in comparison to the cells from the earlier gestational stage. This collagen may therefore play a role in the development of the nuchal ligament.
...
PMID:Fetal calf ligament fibroblasts in culture secrete a low molecular weight collagen with a unique resistance to proteolytic degradation. 631 46

The N-terminal extension peptide of type III procollagen, isolated from foetal-calf skin, contains 130 amino acid residues. To determine its amino acid sequence, the peptide was reduced and carboxymethylated or aminoethylated and fragmented with trypsin, Staphylococcus aureus V8 proteinase and bacterial collagenase. Pyroglutamate aminopeptidase was used to deblock the N-terminal collagenase fragment to enable amino acid sequencing. The type III collagen extension peptide is homologous to that of the alpha 1 chain of type I procollagen with respect to a three-domain structure. The N-terminal 79 amino acids, which contain ten of the 12 cysteine residues, form a compact globular domain. The next 39 amino acids are in a collagenase triplet sequence (Gly- Xaa - Yaa )n with a high hydroxyproline content. Finally, another short non-collagenous domain of 12 amino acids ends at the cleavage site for procollagen aminopeptidase, which cleaves a proline-glutamine bond. In contrast with type I procollagen, the type III procollagen extension peptides contain interchain disulphide bridges located at the C-terminus of the triple-helical domain.
...
PMID:Complete amino acid sequence of the N-terminal extension of calf skin type III procollagen. 633 92

The thermal denaturation of both intracellular and freshly secreted chick embryo tendon type I procollagen was investigated using susceptibility to proteolysis by trypsin and chymotrypsin as a probe for triple-helical conformation. Freshly secreted procollagen from the medium of matrix-free tendon cells in suspension or procollagen within the cells and in the pericellular environment melted at 45 degrees C. In contrast, if freshly secreted procollagen was subjected to the melting procedure after dialysis of the medium against 0.4 M NaCl, 0.1 M Tris HCl, pH 7.4 the protein melted at 42 degrees C, the melting temperature of purified procollagen dissolved in the same buffer. In each of these cases, the thermal denaturation profile was narrow, with a width of 1.0-1.5 degrees C. These results demonstrate that, in situ, procollagen is more stable toward thermal denaturation than was previously thought. This extra margin of thermal stability partially resolves the dilemma of how tissues are able to assemble triple-helical procollagen molecules at body temperatures that closely approach the melting temperature of the purified protein.
...
PMID:Procollagen is more stable in cellulo than in vitro. 671 36

Somatic cell hybrids between mouse and Chinese hamster fibroblasts have been used to identify the chromosome responsible for the synthesis of both mouse type I procollagen subunit chains (MCOLA1 and MCOLA2). Thirty-one separate hybrid clones and subclones from ten separate hybridization events were isolated in hypoxanthine-aminopterin-thymidine (HAT) selection medium and were used for detailed gene-mapping studies. ELISA and "Western blotting" immunochemical analysis were used to detect the production of mouse type I procollagen in each hybrid clone. Mouse and Chinese hamster chromosomes were identified in each hybrid clone by trypsin-Giemsa banding of metaphase chromosome spreads and by isozyme analysis. We have found that mouse type I procollagen production segregates concordantly with mouse superoxide dismutase-1, previously mapped to mouse chromosome 16, and with the presence of mouse chromosome 16 karyotypically. Western blotting immunochemical analysis of the separated mouse procollagen chains produced by each hybrid line demonstrated that apparently the genes for both subunit chains are located on the same chromosome. These studies, therefore, assign the structural genes for mouse type I procollagen pro alpha 1 (MCOLA1) and pro alpha 2 (MCOLA2) chains to mouse chromosome 16.
...
PMID:Assignment of the genes for mouse type I procollagen to chromosome 16 using mouse fibroblast-Chinese hamster somatic cell hybrids. 685 46

Using immunocytochemistry and Northern blot analysis, we investigated the role of cell morphology and reorganization of the cytoskeleton in the expression of transforming growth factor-beta 1 (TGF-beta 1) in human dermal fibroblasts. Disruption of the cytoskeleton was induced by three different agents--trypsin, ethyl-eneglycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA), or cytochalasin--and was confirmed by staining with rhodamine-labeled phalloidin. Immunocytochemical staining with antibodies specific for TGF-beta 1 revealed a cell-shape-related induction of TGF-beta 1. Northern blot analysis of total RNA showed a significant increase in the expression of TGF-beta 1 mRNA as early as 4 h and peaking at 12 h after disruption of the cytoskeleton. Quantitative analysis of TGF-beta 1 mRNA expression at 4 h after treatment with trypsin, EGTA, or cytochalasin C showed increases of 2.6-, 3.3-, and 2.6-fold, respectively. Disruption of the cytoskeleton by trypsin, EGTA, or cytochalasin C increased mRNA for collagenase by 3.8-fold, 2.3-fold, or 2.5-fold, respectively. The expression of mRNA for tissue inhibitor of metalloproteinases I (TIMP-I) also showed a 3.2-fold increase by trypsin, a 3.6-fold increase by EGTA, and a 2.5-fold increase by cytochalasin C. Cell-shape-related induction of TGF-beta 1, collagenase, and TIMP-I genes appears to be selective, as the levels of mRNA for fibronectin and type I procollagen were not significantly altered. These data suggest that gene expression of TGF-beta 1, collagenase, and TIMP-I is governed by the status of the cytoskeleton microfilament organization, which may be a mechanism of gene regulation during cell division, migration, and differentiation, events fundamental to wound healing.
...
PMID:Alteration in cell morphology triggers transforming growth factor-beta 1, collagenase, and tissue inhibitor of metalloproteinases-I expression in normal and hypertrophic scar fibroblasts. 752 43

Systemic sclerosis (SSc; scleroderma) results in the excessive deposition of extracellular matrix components in affected organs. This is partly due to enhanced synthesis; however, the role of degradative processes in this disease is still poorly understood. Sera of 32 patients with SSc (22 with the diffuse, 10 with the limited form) and of six patients with morphoea were assessed using radioimmunoassays for the cross-linked carboxy terminal telopeptide of type I collagen (ICTP) and for the amino terminal propeptide of type I procollagen (PINP) reflecting type I collagen degradation and synthesis, respectively. In 27 of the 32 patients with SSc, the concentration of ICTP was above the upper limit of the normal value (4.6 micrograms/L) and the mean level was clearly elevated at 7.92 micrograms/L. The ICTP concentration correlated with the skin score measuring the extent of the lesions, whereas no such correlation was found for PINP. The ICTP antigen in serum, studied by immunoblotting, had a molecular weight of about twice that of the trypsin-generated fragment isolated from human bone collagen. The mean concentration of serum PINP was 43.9 micrograms/L and no patient exceeded the upper limit of the normal range (80 micrograms/L). We report here for the first time that the concentration of the type I collagen degradation product ICTP in serum shows a close correlation with the extent of skin fibrosis in patients with SSc. We conclude that the increased deposition of type I collagen in this disease is accompanied by an increased turnover of this molecule, indicating a more complex derangement of synthetic and degradative processes than previously acknowledged.
...
PMID:Circulating type I collagen degradation products: a new serum marker for clinical severity in patients with scleroderma? 999 Mar 65

The extent of processing of type III collagen is assessed, and the proportions of type I and III collagens are estimated in atherosclerotic plaques obtained from the carotid artery, common femoral artery, and aorta. The fraction of type III collagen that had retained its amino-terminal propeptide (pN-collagen) was 42% in the soluble extract but only 0.0081% in the insoluble residue. Taken together, only 0.011% of the type III collagen in whole plaques was in the form of type III pN-collagen. Together with the small amounts of the free propeptides of type I procollagen, this finding indicates a low rate of collagen turnover. The amounts of solubilized telopeptides of type I and III collagens were measured, after heat denaturation and trypsin digestion of the collagenous helix, by specific immunoassays for the corresponding trypsin-generated antigens. The mean proportion of type III collagen was 61% (95% confidence interval, 58% to 65%) in the carotid and femoral artery plaques and 56% (95% confidence interval, 44% to 68%) in the aortic specimens. The completely processed and cross-linked type III collagen seems to be the major collagen type in atherosclerotic plaques.
...
PMID:Complete processing of type III collagen in atherosclerotic plaques. 1036 82

Studies on type I procollagen produced by skin fibroblasts cultured from twins with lethal type II of osteogenesis imperfecta (OI) showed that biosynthesis of collagen (measured by L-[5-(3)H]proline incorporation into proteins susceptible to the action of bacterial collagenase) was slightly increased as compared to the control healthy infant. SDS/PAGE showed that the fibroblasts synthesized and secreted only normal type I procollagen. Electrophoretic analysis of collagen chains and CNBr peptides showed the same pattern of electrophoretic migration as in the controls. The lack of posttranslational overmodification of the collagen molecule suggested a molecular defect near the amino terminus of the collagen helix. Digestion of OI type I collagen with trypsin at 30 degrees C for 5 min generated a shorter than normal alpha2 chain which melted at 36 degrees C. Direct sequencing of an asymmetric PCR product revealed a heterozygous single nucleotide change C-->G causing a substitution of histidine by aspartic acid in the alpha2 chain at position 92. Pericellular processing of type I procollagen by the twin's fibroblasts yielded a later appearance of the intermediate pC-alpha1(I) form as compared with control cells.
...
PMID:Studies on type I collagen in skin fibroblasts cultured from twins with lethal osteogenesis imperfecta. 1283 72

In this study, mass spectrometry was used to explore the canine tear proteome. Tear samples were obtained from six healthy dogs, and one-dimensional sodium dodecyl sulphate polyacrylamide gel electrophoresis (1D SDS-PAGE) was used as a first step to separate intact proteins into 17 bands. Each fraction was then trypsin digested and analysed by matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry (MALDI-TOF-MS/MS) to characterize the protein components in each fraction. In total, 125 tear proteins were identified, with MCA (Major Canine Allergen), Serum albumin, UPF0557 protein C10orf119 homolog, Collagen alpha-2(I) chain, Tyrosine -protein kinase Fer, Keratine type II cytoskeletal, Beta-crystallin B2, Interleukin-6 and Desmin occurring as the most confident ones with the highest scores. The results showed that the proteomic strategy used in this study was successful in the analysis of the dog tear proteome. To the best of our knowledge, this study is the first to report the comprehensive proteome profile of tears from healthy dogs by 1D SDS PAGE and MALDI-TOF. Data are available via ProteomeXchange with identifier PXD003124.
...
PMID:Dog Tear Film Proteome In-Depth Analysis. 2670 46


<< Previous 1 2