Structure of antigenic determinants in the N-terminal region of dermatosparactic sheep procollagen type I.
Ontology highlight
ABSTRACT:
SUBMITTER: Rohde H
PROVIDER: S-EPMC1186673 | biostudies-other | 1979 Jun
REPOSITORIES: biostudies-other
Similar Datasets
Project description:The non-collagenous N-terminal segment of type I procollagen from dermatosparactic sheep skin was isolated in the form of the peptide Col 1 from a collagenase digest of the protein. The peptide has a blocked N-terminus, which was identified as pyrrolid-2-one-5-carboxylic acid. Appropriate overlapping fragments were prepared from reduced and alkylated peptide Col 1 by cleavage with trypsin at lysine, arginine and S-aminoethyl-cysteine residues and by cleavage with staphylococcal proteinase at glutamate residues. Amino acid sequence analysis of these fragments by Edman degradation and mass spectrometry established the whole sequence of peptide Col 1 except for a peptide junction (7--8) and a single Asx residue (44), and demonstrated that peptide Col 1 consists of 98 amino acid residues. The N-terminal portion of peptide Col 1 (86 residues) shows an irregular distribution of glycine, whereas the C-terminal portion (12 residues) possesses the triplet structure Gly-Xy and is apparently derived from the precursor-specific collagenous domain of procollagen. The central region of the peptide contains ten cysteine residues located between positions 18 and 73 and shows alternating polar and hydrophobic sequence elements. The regions adjacent to the cysteine-rich portion have a hydrophilic nature and are abundant in glutamic acid. The data are consistent with previous physicochemical and immunological evidence that distinct regions at the N- and C-termini of the non-collagenous domain possess a less rigid conformation than does the central portion of the molecule.
| S-EPMC1186672 | biostudies-other
Project description:Eight monoclonal antibodies have been produced against human pepsin-soluble type III collagen. All antibodies were shown to be highly specific for type III collagen and did not cross-react with a range of other collagen types or connective-tissue proteins. Examination of type III collagen from other species showed that these antibodies had a wide range of species specificities, indicating that several distinct epitopes were being recognized. The location of the epitopes was investigated by using reactivity of the antibodies to CNBr fragments and to sequential fragments formed by tryptic digestion of renaturing type III collagen. These data also indicated that several distinct epitopes were recognized and that they were located over the length of the type III collagen.
| S-EPMC1149995 | biostudies-other
Project description:Knockout of the golgin giantin leads to skeletal and craniofacial defects driven by poorly studied changes in glycosylation and extracellular matrix deposition. Here, we sought to determine how giantin impacts the production of healthy bone tissue by focusing on the main protein component of the osteoid, type I collagen. Giantin mutant zebrafish accumulate multiple spontaneous fractures in their caudal fin, suggesting their bones may be more brittle. Inducing new experimental fractures revealed defects in the mineralization of newly deposited collagen as well as diminished procollagen reporter expression in mutant fish. Analysis of a human giantin knockout cell line expressing a GFP-tagged procollagen showed that procollagen trafficking is independent of giantin. However, our data show that intracellular N-propeptide processing of pro-α1(I) is defective in the absence of giantin. These data demonstrate a conserved role for giantin in collagen biosynthesis and extracellular matrix assembly. Our work also provides evidence of a giantin-dependent pathway for intracellular procollagen processing.
| S-EPMC8103548 | biostudies-literature
Project description:The polymerization of laminin into a cell-associated network--a key step in basement membrane assembly--is mediated by the laminin amino-terminal (LN) domains at the tips of the three short arms of the laminin αβγ-heterotrimer. The crystal structure of a laminin α5LN-LE1-2 fragment shows that the LN domain is a β-jelly roll with several elaborate insertions that is attached like a flower head to the stalk-like laminin-type epidermal growth factor-like tandem. A surface loop that is strictly conserved in the LN domains of all α-short arms is required for stable ternary association with the β- and γ-short arms in the laminin network.
| S-EPMC3059903 | biostudies-literature
Project description:IntroductionFew serum markers are valid and useful for the diagnosis or therapeutic effect monitoring of osteosarcoma. This study aimed to investigate the role of ?-isomerized C-terminal telopeptides (?-CTx) and total procollagen type 1 amino-terminal propeptide (tP1NP) as serological biomarkers for osteosarcoma patients.Materials and methodsA total of 48 patients with osteosarcoma and 55 healthy volunteers were investigated. Serum ?-CTx and tP1NP levels were measured by electrochemiluminescence immunoassay. Data were analyzed by t test with Walth's correction and receiver operating characteristic (ROC) curve analysis.ResultsThe baseline levels of ?-CTx and tP1NP were found to be significantly higher in patients with osteosarcoma than the healthy volunteers. The mean areas under the ROC curves were 0.919 (range, 0.864-0.973) for ?-CTx and 0.866 (range, 0.792-0.939) for tP1NP. The levels of ?-CTx and tP1NP were lower in patients with stable disease after operation than those before operation.ConclusionThese findings support our hypothesis that ?-CTx and tP1NP are promising serum biomarkers for diagnosing or monitoring osteosarcoma.
| S-EPMC4358526 | biostudies-literature
Project description:A peptidase activity capable of excising in a single fragment the N-terminal extension of the precursor of collagen type III (p-N-collagen type III) was observed in calf tendon fibroblast culture medium. A new procedure was developed for detecting this peptidase (p-N-collagen type III peptidase). It is based on the use of 14C-labelled p-N-collagen type III obtained by carboxymethylation of the half-cystine residues with iodo-[14C]acetamide. The released labelled N-terminal extension is soluble in 27% (v/v) ethanol, whereas the uncleaved substrate and the collagen are precipitated under these conditions. The endopeptidase nature of p-N-collagen type III peptidase is supported by the similarity in molecular weight of the product of cleavage of p-N-collagen III by the enzyme to those obtained by cleavage with bacterial collagenase. An apparent Km of 0.3 X 10(-6)M was established. The pH optimum of p-N-collagen type III peptidase is similar to that of p-N-collagen type I peptidase, i.e. about 7.5. Both peptidases are inhibited by dithiothreitol and by Cu2+ and Zn2+, but not by other bivalent ions. p-N-collagen type III peptidase does not cleave p-N-collagen I or p-N-gelatin I. Partial purification of p-N-collagen type III peptidase from fibroblast culture medium was performed by sieve chromatography on Ultrogel AcA-34 to yield two peaks of activity, of mol.wts. 170000 and 100000. Part of the activity was retained on affinity chromatography on concanavalin A--Sepharose. Studied as a function of the age of the culture, p-N-collagen type III peptidase activity produced by tendon fibroblasts parallels that of p-N-collagen type I peptidase and collagen synthesis.
| S-EPMC1162270 | biostudies-other
Project description:PURPOSE:Bone markers can be useful for the diagnosis and treatment of skeletal diseases in children and adolescents. Owing to high skeletal growth velocity and rapid bone turnover, children and adolescents have higher bone marker levels than adults. Thus, a valid age- and sex-specific reference should be established for pediatric populations living in similar environments. We aimed to assess the associations of procollagen type I N-terminal propeptide (P1NP) and osteocalcin with age and sex in a group of healthy Korean children and adolescents. MATERIALS AND METHODS:The participants (290 boys and 290 girls, age range 0-18 years) were Korean outpatients. Serum P1NP and osteocalcin levels were measured in control materials and patient samples by electrochemiluminescence immunoassay using an automated Cobas e411 analyzer. RESULTS:Significant age-dependent variations in bone marker levels were observed in both sexes (p<0.001). The highest P1NP levels were observed during the first year of life; thereafter, levels decreased until puberty. There was no postnatal peak for osteocalcin; however, its levels remained higher than the adult reference range throughout childhood. Significant differences were observed between boys and girls (p<0.05), especially between the ages of 12 and 17 years. Cobas e411 results for P1NP showed satisfactory precision and linearity. CONCLUSION:We established reference data for P1NP and osteocalcin levels in healthy Korean children and adolescents, as the first and only study of these parameters in pre-adulthood in Korea. Cobas e411-quantified bone markers may be useful for determining bone metabolism indices.
| S-EPMC6881701 | biostudies-literature
Project description:Mutations in the type I procollagen C-propeptide occur in ~6.5% of Osteogenesis Imperfecta (OI) patients. They are of special interest because this region of procollagen is involved in α chain selection and folding, but is processed prior to fibril assembly and is absent in mature collagen fibrils in tissue. We investigated the consequences of seven COL1A1 C-propeptide mutations for collagen biochemistry in comparison to three probands with classical glycine substitutions in the collagen helix near the C-propeptide and a normal control. Procollagens with C-propeptide defects showed the expected delayed chain incorporation, slow folding and overmodification. Immunofluorescence microscopy indicated that procollagen with C-propeptide defects was mislocalized to the ER lumen, in contrast to the ER membrane localization of normal procollagen and procollagen with helical substitutions. Notably, pericellular processing of procollagen with C-propeptide mutations was defective, with accumulation of pC-collagen and/or reduced production of mature collagen. In vitro cleavage assays with BMP-1 ± PCPE-1 confirmed impaired C-propeptide processing of procollagens containing mutant proα1(I) chains. Overmodified collagens were incorporated into the matrix in culture. Dermal fibrils showed alterations in average diameter and diameter variability and bone fibrils were disorganized. Altered ER-localization and reduced pericellular processing of defective C-propeptides are expected to contribute to abnormal osteoblast differentiation and matrix function, respectively.
| S-EPMC7521940 | biostudies-literature
Project description:BACKGROUND:Data have shown that healthy children and adolescents have an inadequate intake of zinc, an essential nutrient for growth. It is unclear whether zinc supplementation can enhance bone health during this rapid period of growth and development. OBJECTIVE:The primary aim of this study was to determine the effect of zinc supplementation on biochemical markers of bone turnover and growth in girls entering the early stages of puberty. The secondary aim was to test moderation by race, body mass index (BMI) classification, and plasma zinc status at baseline. METHODS:One hundred forty seven girls aged 9-11 y (46% black) were randomly assigned to a daily oral zinc tablet (9 mg elemental zinc; n = 75) or an identical placebo (n = 72) for 4 wk. Fasting plasma zinc, procollagen type 1 amino-terminal propeptide (P1NP; a bone formation marker), carboxy-terminal telopeptide region of type 1 collagen (ICTP; a bone resorption marker), and insulin-like growth factor I (IGF-I) were assessed at baseline and post-test. Additional markers of bone formation (osteocalcin) and resorption (urinary pyridinoline and deoxypyridinoline) were also measured. RESULTS:Four weeks of zinc supplementation increased plasma zinc concentrations compared with placebo [mean change, 1.8 ?mol/L (95% CI: 1.0, 2.6) compared with 0.2 ?mol/L (95% CI: -0.3, 0.7); P < 0.01]. Zinc supplementation also increased serum P1NP concentrations compared with placebo [mean change, 23.8 ?mol/L (95% CI: -14.9, 62.5) compared with -31.0 ?mol/L (95% CI: -66.4, 4.2); P = 0.04). There was no effect from zinc supplementation on osteocalcin, ICTP, pyridinoline, deoxypyridinoline, or IGF-I. There was no moderation by race, BMI classification, or plasma zinc status at baseline. CONCLUSIONS:Our data suggest that 4 wk of zinc supplementation increases bone formation in premenarcheal girls. Further studies are needed to determine whether supplemental zinc can improve childhood bone strength. This trial was registered at clinicaltrials.gov as NCT01892098.
| S-EPMC4656906 | biostudies-literature
Project description:Huntington's disease is a genetic neurodegenerative disorder resulting from polyglutamine (polyQ) expansion (>36Q) within the first exon of Huntingtin (Htt) protein. We applied X-ray crystallography to determine the secondary structure of the first exon (EX1) of Htt17Q. The structure of Htt17Q-EX1 consists of an amino-terminal alpha helix, poly17Q region, and polyproline helix formed by the proline-rich region. The poly17Q region adopts multiple conformations in the structure, including alpha helix, random coil, and extended loop. The conformation of the poly17Q region is influenced by the conformation of neighboring protein regions, demonstrating the importance of the native protein context. We propose that the conformational flexibility of the polyQ region observed in our structure is a common characteristic of many amyloidogenic proteins. We further propose that the pathogenic polyQ expansion in the Htt protein increases the length of the random coil, which promotes aggregation and facilitates abnormal interactions with other proteins in cells.
| S-EPMC2863341 | biostudies-literature