Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The enzymatic destruction of oxidizing products produced during metabolic reduction of oxygen in the cell (such as singlet oxygen, H2O2 and OH radical) involves the concerted action of superoxide dismutase-which removes O-2 and yields H2O2-and H2O2 removing enzymes such as catalase and glutathione peroxidase. A difference in distribution or ratio of these enzymes in various tissues may result in a different reactivity of oxygen radicals. It was found that in red blood cells superoxide dismutase and catalase are extracted in the same fraction as hemoglobin, while glutathione peroxidase appears to be "loosely" bound to the cellular structure. This suggests that in red blood cells catalase acts in series with superoxide dismutase against bursts of oxygen radicals formed from oxyhemoglobin, while glutathione & peroxidase may protect the cell membrane against low concentrations of H2O2. On the other hand, catalase activity is absent in various types of ascites tumor cells, while glutathione peroxidase and superoxide dismutase are found in the cytoplasm. However, the peroxidase/dismutase ratio is lower than in liver cells, and this may provide an explanation for the higher susceptibility of tumor cells to treatments likely to involve oxygen radicals.
Mol Cell Biochem 1976 Jan 31
PMID:Enzyme defense against reactive oxygen derivatives. II. Erythrocytes and tumor cells. 81 6

Using, in part, comparisons between reconstructed ancestral sequences, homologies are suggested between certain proteins. Genetically related groups seem to be: 1. pancreatic and bacterial nucleases, 2. lysozymes and subtilisins, 3. c type cytochromes, ferredoxins and rubredoxins, 4. b type cytochromes, myoglobins and hemoglobins, catalase, and glutamic dehydrogenase. These homologies suggest that a given ancestral sequence can evolve into quite different tertiary structures.
J Mol Evol 1976 Apr 09
PMID:On certain homologies between proteins. 93 76

1. Functional and biochemical studies were performed on the small intestine of control rats, and the results were compared with similar studies on animals given triparanol at a dosage of 0.114 mmol/kg daily for 10 days. The animals given triparanol were fed with either standard rat food or a gluten-free diet. 2. By using a recirculating-perfusion technique in vivo, it was shown that absorption of galactose from an 8 mmol/l solution was impaired in the ileum but not in the jejunum of the triparanol-treated rats. 3. Assays of marker enzymes for the principal subcellular organelles were performed on isolated jejunal and ileal enterocytes. In the ileum there was a striking decrease in lysosomal enzyme activities and a smaller but significant decrease of lactate dehydrogenase, catalase and malate dehydrogenase activities. In the jejunum there was no significant change in the activities of these enzymes. 4. Measurements of lysosomal integrity indicated that ileal lysosomal fragility was markedly increased and that jejunal lysosomes were affected to a much smaller extent. 5. These effects of triparanol could not be ameliorated by feeding with a gluten-free diet.
Clin Sci Mol Med 1976 Jul
PMID:Functional and biochemical evidence of damage to enterocytes induced by triparanol: role of lysosomes and the effect of gluten-free diet. 93 62

Certain ocular proteins have been found to be chemically modified by exposure to near-UV light (320-390 nm) in the presence of tryptophan. Colored and fluorescent tryptophan photoproducts bind firmly to proteins, thereby altering their physico-chemical properties. The question of whether such a reaction would inhibit the catalytic action of catalase is herein raised. When solutions of bovine liver catalase were re-incubated up to 24 hr under near-UV with preirradiated tryptophan and dialyzed, most of the ability of the enzyme to decompose H2O2 was lost. Similar results occurred for catalase activities of bovine cornea and lens epithelia. The enzyme protein exhibited altered UV absorption and fluorescence spectra and increased electrophoretic mobility after binding photoproducts, Near-UV light photoproducts of tryptophan are thus capable of deactivating crystalline and tissue catalase.
Mol Cell Biochem 1976 Jun 15
PMID:Inactivation of catalase by near ultraviolet light and tryptophan photoproducts. 94 May 47

The first intron of the human Pro alpha 1(I) collagen gene contains an orientation-dependent enhancer composed of both positive and negative cis-acting elements involved in the transcriptional regulation of this gene. Deletion of a 360 bp Sau 3A intronic fragment spanning nucleotide +494 to +854 (S360) resulted in dramatic down-regulation of pCOL-KT (Thompson et al., J Biol Chem 266: 2549-2556, 1991). Using a DNaseI protection assay, we demonstrate a single footprint located at +590 to +615 in the S360 fragment; nuclear extracts prepared from mesenchymal and nonmesenchymal cells exhibited similar binding characteristics. A double stranded oligonucleotide representing a consensus Ap-1 binding sequence competed with S360 for binding. In contrast to what occurred in response to S360 deletion which was always accompanied by reduced expression, the deletion of the Ap-1 binding site (+598 to +off) caused either increased or decreased expression of the reporter gene depending on the target cell. Site-directed mutations in the Ap-1-like cis-element of Pro alpha 1(I) were also tested in transient expression assays. Consistent with the paradoxical results of Ap-1 deletion, we observed that the functional consequences of mutations in the Ap-1 site also varied in different cells. In A204 cells, one point mutation, which resulted in the loss of protein binding to S360, led to increased CAT activity while another point mutant, which retained binding of the Ap-1 like trans-acting factor(s), showed decreased CAT expression. The effects of these two mutations in the HFL-1 cells were exactly opposite of what was seen for A204 cells. Based on these observations, we postulate that the Ap-1 site plays a critical role in the transcriptional activity of the human Pro alpha 1(I) gene. The implications of an apparently dual mode of regulation through a single cis-regulatory element are discussed.
Mol Cell Biochem 1992 Dec 16
PMID:An AP-1-like motif in the first intron of human Pro alpha 1(I) collagen gene is a critical determinant of its transcriptional activity. 129 7

We have investigated the antioxidant properties of V79 Chinese hamster cells rendered resistant to menadione by chronic exposure to increasing concentrations of this quinone. MD1, a clone of resistant cells, was compared to the parental M8 cells; the former showed increased activity of catalase (3 fold), glutathione peroxidase (1.6 fold) and DT-diaphorase (2.6 fold), as well as an increase in glutathione (3.2 fold). Although one of the products of menadione metabolism is superoxide anion, no changes in total superoxide dismutase activity was observed in MD1 cells. MD1 menadione resistant cells were also resistant to killing by hydrogen peroxide and contained tandem duplication of chromosome 6. A similar duplication of chromosome 6 was seen in several independently derived menadione resistant clones and therefore seems closed linked to the establishment of the resistance. Upon removal of menadione from the medium, some of these properties of MD1 cells, viz., resistance to menadione, elevated glutathione levels, and glutathione peroxidase activity, were lost and the cells resembled M8 cells. However, resistance to H2O2, elevated catalase activity and the duplicated chromosome remained stable for more than 40 cell passages in the absence of menadione. The increase in catalase activity was correlated with an increase in catalase mRNA content and a 50% amplification of catalase gene, as determined, respectively, by Northern and Southern blot analysis. The role of the chromosome 6 duplication in resistance to oxidative stress remains to be established. It is not responsible directly for elevated catalase levels since the catalase gene is on chromosome 3.
Mol Cell Biochem 1992 Dec 16
PMID:Menadione-resistant Chinese hamster cell variants are cross-resistant to hydrogen peroxide and exhibit stable chromosomal and biochemical alterations. 129 12

A full-length chinook salmon (Oncorhynchus tschawytscha) prolactin (PRL) gene, the first genomic clone of a teleost prolactin, was isolated and fully sequenced. The chinook PRL genomic sequence spans 6.4 Kb, including 2.4 Kb of 5' flanking sequence, 3.0 Kb representing the five exons and four introns of the complete PRL gene, and 0.9 Kb of 3' flanking sequence. The transcriptional start site of the PRL gene was mapped through the agreement of both primer extension and S1 nuclease protection assay. The 5' flanking region of the PRL gene was searched for potential cis-acting elements based on the consensus binding site of trans-acting factor Pit-1, known to be involved in PRL gene expression in mammals. Functional analysis of PRL promoter by the transient transfection of several PRL promoter/CAT chimeric plasmids into rainbow trout pituitary cells suggests a functional PRL promoter whose cell-specific activity is most likely governed by both positive and negative mechanisms.
Mol Mar Biol Biotechnol 1992 Apr
PMID:A gene encoding chinook salmon (Oncorhynchus tschawytscha) prolactin: gene structure and potential cis-acting regulatory elements. 130 11

We attempted to produce transgenic rainbow trout embryos by fertilizing eggs with sperm incubated with linearized plasmids. One experiment was conducted with the construct pBGH7 in the medium MMSF, with or without DMSO, at 2 concentrations of sperm cells and a relatively low concentration of DNA. The DNA was also in contact with the eggs during insemination and during the first minutes of egg activation. The second experiment was conducted with the construct CMVCAT in the medium MMSF, at 2 concentrations of sperm cells and a much higher concentration of DNA. The DNA was also present during the insemination. DNA analyses and dosages of CAT activity did not permit detection of any transgenic fry. However, one result suggests that sperm cells can capture part of the linear DNA in teh conditions tested.
Mol Mar Biol Biotechnol
PMID:No transgenic rainbow trout produced with sperm incubated with linear DNA. 130 18

The ability of a promoter sequence to drive expression of a reporter gene can be determined by direct injection of copies of the cloned sequence into fish muscle, followed by biopsy of muscle from the site of injection. We describe a set of experiments in which copies of the constructs FV1 and FV2, both comprising a carp beta-actin promoter sequence spliced to the bacterial reporter gene CAT, were injected into the muscle of tilapia fish )Oreochromis niloticus) of between 5 and 8 cm body length. The site of injection was carefully determined so that biopsy samples could be recovered from the injection site 24 hours, 48 hours, and 7 days after injection. Biopsy samples of muscle were homogenized and used for CAT assays. CAT activity was successfully detected in many of the muscle samples.
Mol Mar Biol Biotechnol
PMID:Fish transgene expression by direct injection into fish muscle. 130 19

Activated neutrophils produce a wide array of products (free radicals, arachidonate metabolites, degradative enzymes), cause hemodynamic effects and increased permeability in isolated blood-free perfused lungs, and evoke direct injury to cultured endothelial cells. The aims of this study were to investigate the response of isolated rat pulmonary arterial rings to activated neutrophils, the role of intact endothelium in these responses, and which neutrophil products were responsible for the observed effects. Neutrophils activated with phorbol myristate acetate caused an initial increase in tension and a subsequent decreased recovery contraction to KCl. Neutrophils activated with formylmethionylleucylphenylalanine also caused an increase in tension but did not result in decreased recovery, suggesting different mechanisms for these two effects. The contractile response was dependent on endothelium, whereas the decline in recovery still occurred in the absence of endothelium. Filtrate from activated neutrophils did not cause the contractile response, but recovery was decreased. Neither addition of catalase + superoxide dismutase nor decreased superoxide release due to prior activation of neutrophils altered the initial contraction or the decline in recovery contractile ability, suggesting that oxygen free radical products were not responsible for either effect. The cyclooxygenase inhibitors (ibuprofen and indomethacin), the thromboxane A2 synthetase inhibitor (OKY-046), and pretreatment of the neutrophils with aspirin inhibited the contractile response but did not prevent the decrease in recovery. A mixture of antiproteases did not protect the arterial muscle from the decline in recovery. Although cyclooxygenase products may be involved in initiating the contraction in response to activated neutrophils, the mechanism resulting in subsequent loss of force-developing ability is unclear.
Am J Respir Cell Mol Biol 1992 Mar
PMID:Activated neutrophils alter contractile properties of the pulmonary artery. 131 94


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