Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.31 (beta-glucuronidase)
 7,680 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

beta-Glucuronidase (GUS) has become an important enzyme model for the genetic study of molecular disease, enzyme realization, and therapy, and for the biogenesis and function of the lysosome and lysosomal enzymes. The genetics of human beta-glucuronidase was investigated utilizing 188 primary man-mouse and man-chinese hamster somatic cell hybrids segregating human chromosomes. Cell hybrids were derived from 16 different fusion experiments involving cells from ten different and unrelated individuals and six different rodent cell lines. The genetic relationship of GUS to 28 enzyme markers representing 19 linkage groups was determined, and chromosome studies on selected cell hybrids were performed. The evidence indicates that the beta-glucuronidase gene is assigned to chromosome 7 in man. Comparative linkage data in man and mouse indicate that the structural gene GUS is located in a region on chromosome 7 that has remained conserved during evolution. Involvement of other chromosomes whose genes may be important in the final expression of GUS was not observed. A tetrameric structure of human beta-glucuronidase was demonstrated by the formation of three heteropolymers migrating between the human and mouse molecular forms in chromosome 7 positive cell hybrids. Linkage of GUS to other lysosomal enzyme genes was investigated. beta-Hexosaminidase (HEXB) was assigned to chromosome 5; acid phosphatase2 (ACP2) and esterase A4 (ES-A4) were assigned to chromosome 11; HEXA was not linked to GUS; and alpha-galactosidase (alpha-GAL) was localized on the X chromosome. These assignments are consistent with previous reports. Evidence was not obtained for a cluster of lysosomal enzyme structural genes. In demonstrating that GUS was not assigned to chromosome 9 utilizing an X/9 translocation segregating in cell hybrids, the gene coding for human adenylate kinase1 was confirmed to be located on chromosome 9.
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PMID:Human beta-glucuronidase: assignment of the structural gene to chromosome 7 using somatic cell hybrids. 55 90

In this paper we demonstrate that RNA sequences present upstream and downstream of a reporter gene coding region play an important role in determining the amount of protein produced from an mRNA. A translational enhancer, omega, derived from tobacco mosaic virus, when present at the 5'-end of beta-glucuronidase mRNA increased the efficiency of translation 16-fold to 18-fold in electroporated tobacco or carrot protoplasts, and threefold to 11-fold in maize or rice protoplasts. The presence of omega did not alter the half-life of the mRNA in vivo. We also demonstrate for the first time that a minimum polyadenylated tail length of 25 adenylate residues is sufficient to substantially increase the expression and half-life of the reporter mRNA in plants. When in vitro-produced mRNAs were synthesized such that extra sequence was added to the 3'-end of the poly(A) tail, however, the final level of expression was decreased up to 80%. Omega, the translational enhancer, and a poly(A) tail function independently of each other; their combined effect on translation, when both are present in an mRNA, is the multiplication of their individual effects. Histochemical analysis for the presence of beta-glucuronidase in tobacco established that virtually all viable cells receive mRNA during electroporation. Video image analysis of tobacco protoplasts electroporated with luciferase mRNA demonstrated that there is a wide range in the level of expression of this marker. Carrier RNA, when present during electroporation, had only a modest effect on increasing mRNA uptake. Reporter mRNA expression in electroporated protoplasts was directly proportional to the input mRNA up to at least 30 micrograms/ml.
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PMID:Visualizing mRNA expression in plant protoplasts: factors influencing efficient mRNA uptake and translation. 253 5

Osmotic release of beta-glucuronidase from polymorphonuclear leukocyte lysosomes is inhibited by catecholamines and adenosine 3',5'-monophosphate, and accelerated by cholinergic agents and guanosine 3',5'-monophosphate. These actions are specific for the sympathetic and parasympathetic neurotransmitters and for the two cyclic nucleotides, as phenylephrine, tyramine, choline, adenosine 5'-monophosphate and guanosine 5'-monophosphate do not inodify lysosomal enzyme release.
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PMID:Enzyme release from polymorphonuclear leukocyte lysosomes: regulation by autonomic drugs and cyclic nucleotides. 435 Apr 74

Selective release of inflammatory materials from leukocyte lysosomes is reduced by compounds which increase cyclic 3',5'-adenosine monophosphate (cAMP) levels in suspensions of human leukocytes and is augmented by agents which increase cyclic 3',5'-guanosine monophosphate (cGMP) levels in these cell suspensions. Lysosomal enzymes are released in the absence of phagocytosis when cytochalasin B (5 mug/ml) converts polymorphonuclear leukocytes (PMN) to secretory cells: lysosomes merge directly with the plasma membrane upon encounter of PMN with zymosan, and cells selectively extrude substantial proportions of lysosomal, but not cytoplasmic enzymes. beta-Adrenergic stimulation of human leukocytes produced a dose-related reduction in beta-glucuronidase release (blocked by 10(-6) M propranolol) whereas alpha-adrenergic stimulation (phenylephrine plus propranolol) was ineffective. In contrast, the cholinergic agonist carbamylcholine chloride enhanced enzyme secretion, an effect blocked by 10(-6) M atropine. Incubation of cells with exogenous cAMP or with agents that increase endogenous cAMP levels (prostaglandin E1, histamine, isoproterenol, and cholera enterotoxin) reduced extrusion of lysosomal enzymes; in contrast, exogenous cGMP and carbamylcholine chloride (which increases endogenous cGMP levels), increased beta-glucuronidase release. Whereas colchicine (5 x 10(-4) M), a drug which impairs microtubule integrity, reduced selective enzyme release, deuterium oxide, which favors microtubule assembly, enhanced selective release of lyosomal enzymes. The data suggest that granule movement and acid hydrolase release from leukocyte lysosomes requires intact microtubules and may be modulated by adrenergic and cholinergic agents which appear to provoke changes in concentrations of cyclic nucleotides.
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PMID:Mechanisms of lysosomal enzyme release from human leukocytes. II. Effects of cAMP and cGMP, autonomic agonists, and agents which affect microtubule function. 435 15

Human neutrophilic leukocytes release neutral protease and beta-glucuronidase during cell contact with, and phagocytosis of, zymosan particles treated with rheumatoid arthritic serum. Release of lysosomal enzymes is inhibited by epinephrine and adenosine 3',5'-monophosphate (cyclic AMP), but not by phenylephrine or adenosine 5'-monophosphate. Inhibition of enzyme release by epinephrine may be mediated by cyclic AMP because the cyclic AMP in the neutrophils is increased by epinephrine treatment at the time when enzyme release is reduced.
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PMID:Hormonal control of neutrophil lysosomal enzyme release: effect of epinephrine on adenosine 3',5'-monophosphate. 435 40

We have studied the regeneration of adenosine triphosphate (ATP) in the glycolytic pathway in platelets with a 75% reduction in hexokinase (HK) activity and have investigated aggregation and Ca2+ secretion. HK-deficient platelets had a normal glycolytic flux in the resting state, but responded insufficiently to stimulation with thrombin (5 U/ml). In contrast, glycogen contents and glycogenolysis were normal. When the metabolic adenine nucleotides were labeled with 14C-adenine, the patient's platelets showed a normal adenylate energy charge and a normal level of 14C-ATP. However, the inhibitor of mitochondrial energy generation, CN-, induced a weaker fall in 14C-ATP in the patient's platelets than in the controls. Analysis of secretion markers revealed decreased amounts of granule-bound ATP and secretable Ca2+, whereas granule-bound adenosine diphosphate (ADP), beta-thromboglobulin, N-acetyl-beta-D-glucosaminidase, and beta-glucuronidase were within the normal range. Aggregation and Ca2+ secretion induced by 5 U/ml thrombin were normal and were not changed in the presence of inhibitors of mitochondrial and glycogenolytic energy generation. Aggregation was also normal at 0.1 U/ml thrombin and was independent of these inhibitors, but Ca2+ secretion was greatly impaired when mitochondrial and glycogenolytic ATP resynthesis was abolished. These findings indicate that a severe reduction in HK activity causes insufficient acceleration of the glycolytic flux during stimulation with thrombin. This leads to impaired dense granule secretion in conditions where secretion depends on concurrent ATP resynthesis and glycolysis is rate limiting.
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PMID:Platelet functions and energy metabolism in a patient with hexokinase deficiency. 668 46

In intact plants, the shoot apex grows predominantly and inhibits outgrowth of axillary buds. After decapitation of the shoot apex, outgrowth of axillary buds begins. This phenomenon is called an apical dominance. Although the involvement of auxin, which represses outgrowth of axillary buds, and cytokinin (CK), which promotes outgrowth of axillary buds, has been proposed, little is known about the underlying molecular mechanisms. In the present study, we demonstrated that auxin negatively regulates local CK biosynthesis in the nodal stem by controlling the expression level of the pea (Pisum sativum L.) gene adenosine phosphate-isopentenyltransferase (PsIPT), which encodes a key enzyme in CK biosynthesis. Before decapitation, PsIPT1 and PsIPT2 transcripts were undetectable; after decapitation, they were markedly induced in the nodal stem along with accumulation of CK. Expression of PsIPT was repressed by the application of indole-3-acetic acid (IAA). In excised nodal stem, PsIPT expression and CK levels also increased under IAA-free conditions. Furthermore, beta-glucuronidase expression, under the control of the PsIPT2 promoter region in transgenic Arabidopsis, was repressed by an IAA. Our results indicate that in apical dominance one role of auxin is to repress local biosynthesis of CK in the nodal stem and that, after decapitation, CKs, which are thought to be derived from the roots, are locally biosynthesized in the nodal stem rather than in the roots.
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PMID:Auxin controls local cytokinin biosynthesis in the nodal stem in apical dominance. 1650 92