Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P15088 (mast cell)
 14,925 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

High density lipoproteins were isolated from plasma of white Leghorn hens by ultracentrifugal flotation between densities 1.063 and 1.210 g/ml. After delipidation, the lipid-free proteins were fractionated by chromatography on Sephadex G-150 in urea; one major apolipoprotein was isolated and characterized. From its chemical, physical and immunochemical properties, the major apoprotein from hen high-density lipoproteins has characteristics similar to the major apoprotein of human high density lipoproteins, apoA-I. Thus the hen protein has been designated hen apoA-I. Hen apoA-I has a molecular weight of approximately 28 000 as determined by polyacrylamide gel electrophoresis in sodium dodecyl sulfate. Its calculated molecular weight from its 234 constituent amino acids is 26 674. Hen apoA-I differed from its human counterpart by containing isoleucine. Treatment of hen apoA-I with carboxypeptidase A yielded a COOH-terminal sequence of Leu-Val-Ala-Gln. Automatic Edman degradation of the apoprotein gave an NH2-terminal sequence of Asp-Glu-Pro-Gln-Pro-Glu-Leu. Hen apoA-I had a circular dichroic spectrum typical of alpha-helical structures; the calculated helicity was 90%. Goat antisera prepared to hen apoA-I formed precipitin lines of complete identity to the hen apoprotein but lines of only partial identity to human apoA-I. These studies show that the major apoprotein from hen and human high-density lipoproteins have similar properties to each other suggesting a common physiologic function.
 ...
PMID:Isolation and characterization of the major apolipoprotein from chicken high density lipoproteins. 17 37

The phytohemagglutinin mitogenic proteins derived from Phaseolus vulgaris comprise a class of five glycoproteins that are isomeric tetramers composed of varying proportions of two different subunits (L and R). Within the native tetramer, the L subunit is a potent leukoagglutinin and mitogen that lacks hemagglutinating properties, whereas the R subunit is a potent hemagglutinin with little or no mitogenic activity. The subunits have been isolated in homogeneous form by isoelectric focusing in 8 M urea. Previous work has shown that they have equal molecular weights and differ in amino-acid sequence from residues 1-7, but are identical in positions 8-24 [(1973) J. Exp. Med. 138, 939-951]. We now report amino-acid composition studies which reveal striking similarities between the subunits. Both lack methionine and cysteine. The twelfth residue in each subunit is a glycosylated asparagine, with the identical carbohydrate composition in each. The last three residues of the subunits, as determined by carboxypeptidase A digestion, are identical. Tryptic peptide mapping of the succinylated phytohemagglutinin subunits reveals a high degree of similarity. We conclude that the substantial difference in biological properties among the tetrameric phytohemagglutinin mitogens is a result of relatively restricted differences in the primary structure of their constituent subunits.
 ...
PMID:Extensive homology between the subunits of the phytohemagglutinin mitogenic proteins derived from Phaseolus vulgaris. 105 14

1. D-Galactose dehydrogenase from Pseudomonas saccharophila (molecular weight 102 000) dissociates in 8 M urea into its subunits (molecular weight 25 000) which migrate in polyacrylamide gels, containing 8 M urea, as a single band. 2. The N-terminal residue determination by the dansyl method revealed only serine. 3. The C-terminal group determination with carboxypeptidase A and B indicated the sequence -Tyr-His-Leu. Leucine as the single C-terminal amino acid was confirmed by the tritiation method and by tritiation and subsequent degradation with carboxypeptidases. 4. The fragmentation of D-galactose dehydrogenase (24 mol methionine per mol enzyme) by CNBr resulted in six peptides, as detected in disc electrophoresis and substantiated by end group determination, indicating the identity of the subunits. 5. The treatment of D-galactose dehydrogenase (24 mol lysine and 52 mol arginine per mol enzyme) with trypsin and subsequent peptide mapping showed 21, perhaps 22 peptides, indicating a structure comprising four identical subunits.
 ...
PMID:Subunit structure of D-galactose dehydrogenase from Pseudomonas saccharophila. 113 86

The subunits of the two molecular forms (A and B) of the Dolichos biflorus lectin were isolated by ion-exchange chromatography on DEAE-cellulose in 8.0 M urea. Subunits IA and IIA which comprise the predominant molecular form A of the lectin were found to have molecular weights of 27,700 and 27,300, respectively, as determined by sedimentation equilibrium studies in 8.0 M urea. These subunits have similar amino acid compositions and each have alanine at their amino-terminal ends. Comparison of the IA and IIA subunits by immunodiffusion against antisera to the seed extract as well as to subunits IA and IIA showed no antigenic differences between the two subunits. Carboxyl terminal analyses of subunits IA and IIA with carboxypeptidase A produced an essentially simultaneous release of both leucine and valine residues from subunit IA; no detectable amino acids were released from subunit IIA under identical conditions. The data suggest that the molecular form A of the lectin (molecular weight 113,000, Carter and Etzler, 1975) consists of four subunits with a possible stoichiometry of IA2IIA2. Other possible arrangements of the subunits are discussed.
 ...
PMID:Isolation and characterization of subunits from the predominant form of Dolichos biflorus lectin. 114 75

The activation of the clotting system is an important process during inflammation to contain the injury and initiate tissue repair. In the present study, we investigated the effect of mast cells on fibrin deposition in reverse passive Arthus reaction in mast cell-deficient WBB6F1-W/Wv(W/Wv) and control WBB6F1-(+)/+(+/+) mice, that were given 125I-labeled fibrogen intravenousty. An antibody dose-dependent increase in radioactivity was observed in the challenged skin sites. Sequential water and urea extractions characterized the radioiodinated fibrinogen derivatives present in the tissue. The radioactivity found in the various fractions of the stimulated samples from +/+ was 2-10-fold higher than that in specimens from W/Wv mice. The greatest difference was observed in the urea-insoluble pellet (cross-linked fibrin and its early degradation products). Reconstitution of W/Wv mice with mast cells augmented the response to levels similar to those in +/+ mice. Pretreatment with the antihistamine pyrilamine blocked the accumulation of 125I-labeled fibrinogen and its derivatives by approximately 70% in +/+ but not in W/Wv mice. Inhibition of leukotriene synthesis by A-63162 markedly decreased the accumulation of iodinated fibrinogen in both +/+ and W/Wv mice. The data suggest that mast cells and their vasoactive mediator histamine contribute to the exudation of clotting factors, which results in fibrin deposition and that mast cells also enhance fibrin cross-linkage.
 ...
PMID:Mast cells contribute to fibrin deposition in reverse passive Arthus reaction in mouse skin. 138 12

Interstitial cystitis is an inflammatory disease of unknown etiology. To facilitate the study of the pathophysiology of interstitial cystitis, an animal model that correlates with the clinical features of interstitial cystitis and expresses histologic features consistent with those observed in interstitial cystitis patients was developed. Various strains of mice were immunized with a syngeneic bladder homogenate to determine their susceptibility to the induction of autoimmune cystitis. Of 3 mouse strains tested, only the Balb/cAN mice reproducibly developed the clinical correlates and histological features consistent with those observed in interstitial cystitis. In a blinded pathologic review, autoreactive Balb/cAN bladders were correctly distinguished from chronic bacterial cystitis, sham treated bladders and normal control bladders. Edema, fibrosis, perivascular lymphocytic infiltrations and detrusor mast cell accumulation were apparent in 75% of the Balb/cAN mice 2 weeks after immunization and 100% at 4 weeks. These histologic features plateaued and remained stable for at least 6 months. Grossly, the immunized mouse bladders were fibrotic and contracted with a significantly (p < .05) decreased fluid capacity. On hydrodistension, increased vascular prominence and petechial hemorrhage (glomerulations) were evident. Instillation of 14C-urea demonstrated increased permeability in immunized bladders compared with controls. A cellular autoimmune basis for the cystitis is supported by adoptive transfer studies. Spleen cells from experimental mice but not controls transferred the histological features of the disease to naive mice. These studies outline the development of a new experimental autoimmune cystitis model that expresses features similar to those frequently observed in human interstitial cystitis, and may provide a model for the study of the inflammatory process associated with interstitial cystitis. Furthermore, these data suggest a possible role for cellular immune components in interstitial cystitis.
 ...
PMID:Experimental autoimmune cystitis: a potential murine model for ulcerative interstitial cystitis. 143 51

In bovine adrenal zona glomerulosa, atrial natriuretic factor (ANF) exerts its physiological effect through high-affinity binding to specific membrane receptors. On studying further the molecular properties of the ANF receptor binding domain, we have observed that incubation of intact or solubilized bovine adrenal zona glomerulosa membranes with 125I-ANF-(99-126) followed by u.v. irradiation results in the irreversible labelling of a 130 kDa protein corresponding to the ANF-RI receptor. This process is time-, protein- and 125I-ANF-dependent. The apparently covalent nature of this complex is documented by its resistance to heat, guanidine hydrochloride, urea and trichloroacetic acid denaturation. Photolabelling with underivatized 125I-ANF is much more efficient with the ANF-R1 than with the ANF-R2 receptor. After photolysis, the covalently linked 125I-ANF is still sensitive to digestion by carboxypeptidase A, suggesting that ANF is linked by its N-terminal end to the receptor upon u.v. irradiation and that its C-terminal end is still freely accessible. Aerobic conditions and lipids are required for the photolabelling, suggesting a role in this process for malondialdehyde, a highly reactive secondary product associated with u.v.-induced lipid peroxidation. This simple method should provide a powerful tool in the accurate characterization of the hormone-binding domain of the ANF receptor.
 ...
PMID:Photoaffinity labelling of atrial natriuretic factor (ANF)-R1 receptor by underivatized 125I-ANF. Involvement of lipid peroxidation. 215 78

The isolated activation segment (asA) from pig pancreatic procarboxypeptidase A was studied by 1H-n.m.r. spectroscopy over a wide range of solution conditions. Isolated asA shows many characteristics of compactly folded globular proteins, such as the observation of perturbed positions for resonances from methyl groups, alpha-carbon atoms, histidine residues and the tyrosine residue. The single tyrosine residue (Tyr-70) exhibits a very high pKa, and both histidine and tyrosine residues show slow chemical modification (deuteration and iodination). In contrast, asA shows rapid NH exchange. Analysis of the spectra by pH titration and nuclear Overhauser effects revealed several residue interactions. Quantitative analysis of deuterium and tritium exchange allowed the assignment of the histidine C-2-H resonances to their respective residues in the sequence. His-66, the closest to the sites of proteolytic attack in the proenzyme, is shown to be the most accessible to solvent in procarboxypeptidase A. It was also shown that asA is thermally very stable ['melting' temperature (Tm) 88 degrees C] and requires a high urea concentration for denaturation (6.25 M, at pH 7.5). Evidence is presented for some degree of conformational flexibility in the premelting range, a feature that could be ascribed to the preponderance of helical secondary structure and to the lack of disulphide bridges. The free solution structure of asA is probably unchanged when it binds to carboxypeptidase A.
 ...
PMID:1H-n.m.r. studies of the isolated activation segment from pig procarboxypeptidase A. 232 81

Three murine monoclonal antibodies (mAb 100, 104, and 121) elicited against carboxypeptidase A (CPA) were prepared and characterized. All three mAbs recognize the same or partially overlapping sites of CPA. This is corroborated by the lack of antibody additivity in the ELISA assay carried out in the presence of pairs of mAbs, the similarity in molecular weight of the immunocomplex formed between CPA and one of the mAbs in the presence of another, and also a competition experiment in which one of the mAbs was labeled enzymatically. The three mAbs do not affect the enzymatic activity of CPA. Even at high concentrations, they do not recognize carboxypeptidase B (CPB) in spite of the similar tertiary structure and the 50% homology in amino acid sequence with CPA. This antigenic determinant is located on one of the four cyanogen bromide fragments of CPA. On the basis of the known sequences of the two enzymes, criteria which predict high antigenicity, and experimental data using synthetic peptides, such a determinant was found to be located within the amino acid sequence from residues 209 to 218 of the CPA molecule. The mAbs prepared detect conformational alterations in the above enzyme epitope when the enzyme is exposed to various conditions. The binding of the mAbs to CPA adsorbed onto a polystyrene plate is characterized by apparent binding constants higher by 1 or 2 orders of magnitude than those characterizing the interaction of the mAbs with CPA in solution. The mAbs also readily detect both conformational alterations of CPA on treatment with urea and subtle, reversible conformational alterations on removal of zinc from the active site of the enzyme.
 ...
PMID:Localization of a highly immunogenic region of carboxypeptidase A recognized by three different monoclonal antibodies and their use in the detection of subtle conformational alterations in this enzyme region. 246 66

Apolipoproteins C are involved in many ways in the metabolism of plasma lipoproteins. Apolipoproteins C from the delipidated VLDL of 35 controls and 165 normo- and hyperlipoproteinemic patients were analyzed by isoelectric focusing on an immobilized pH gradient, pH 4.0-5.0, with 7 M urea, which raised the apparent pH range to 4.8-5.7. This method is an improvement over conventional isoelectric focusing with carrier ampholytes with regard to both resolution and reproducibility. Due to the high resolution (0.1 pH units per cm) additional apolipoprotein C-III bands: C-III0 A1, C-III0 A2, C-III1 C and C-III2 C (the designations A, anodic, and C, cathodic, refer to direction of migration on IEF in relation to the main band) are described for the first time. The possible artifactual nature of these protein bands could be excluded. Cleavage with neuraminidase and peptidases, immunological detection and/or two-dimensional electrophoresis were used to obtain more information. The additional bands seem, in part, to be hydrolysis products of carboxypeptidase A (C-III1 C, C-III2 C). The appearance of C-III1 C and C-III2C was dependent upon the serum triglyceride concentration. The percent distribution of C apolipoproteins in very low density lipoproteins (VLDL) from control serum agreed with previously published data. Apolipoproteins C can also be focused in immobilized pH gradients from VLDL and serum without delipidation.
 ...
PMID:Analysis of human apolipoproteins C by isoelectric focusing in immobilized pH gradients. 324 52


1 2 3 4 Next >>