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

The purposes of this study are to develop an in vivo cell system that is suitable for the immunofluorescent detection of transiently expressed proteins targeted to plant peroxisomes and to determine whether a C-terminal serine-lysine-leucine (SKL) tripeptide, a consensus-targeting signal for mammalian peroxisomes, also targets proteins to plant peroxisomes. Protoplasts from mesophyll cells and from suspension-cultured cells initially were examined for their potential as an in vivo import system. Several were found suitable, but based on a combination of criteria, suspension-cultured tobacco (Nicotiana tabacum L. cv Bright Yellow 2) cells (TBY-2) were chosen. The tobacco cell extracts had catalase activity, and two polypeptides of approximately 55 and 57 kD specifically were detected on immunoblots with anti-cottonseed catalase immunoglobulins G as the probe. Indirect immunofluorescence microscopy with these immunoglobulins G revealed a punctate labeling pattern indicative of endogenous catalase localization within putative TBY-2 peroxisomes. The cells did not have to be completely converted to protoplasts for optimal microscopy; treatment with 0.1% (w/v) pectolyase for 2 h was sufficient. Microprojectile bombardment proved superior for transient transformation of the TBY-2 cells with plasmids encoding beta-glucuronidase, or chloramphenicol acetyltransferase (CAT), or CAT with an added C-terminal tripeptide (CAT-SKL). C-terminal SKL is a consensus, type 1, peroxisome targeting signal. Double indirect immunofluorescent labeling showed that CAT-SKL co-localized with endogenous catalase. Non-punctate, diffuse localization of CAT without SKL provided direct evidence that the C-terminal SKL tripeptide was necessary and sufficient for targeting of CAT to plant peroxisomes. These data demonstrate the effectiveness of this peroxisome targeting signal for plant cells.
...
PMID:Development and application of an in vivo plant peroxisome import system. 777 May 24

In this work we studied the effect of Prothymosin alpha (ProT alpha) and other thymic factors on the expression of Thy 1.2 antigen (a T-cell marker) and the activities of adenosine deaminase (ADA, E.C. 3.5.4.4), N-acetyl-beta-D-glucosaminidase (NABG, E.C. 3.2.1.30), beta-glucuronidase (BG, E.C. 3.1.1.1) and serine-esterase (SE, E.C. 3.4.21)., the levels of which change during the T-cell differentiation process among small thymocytes obtained from C57BL/6 mice. Incubation of small thymocytes in the presence of ProT alpha, Thymus Extracts (TE) or supernatants prepared from thymic stromal cells (TSCS) or thymocytes (TS) reduced the proportion of cells killed by anti-Thy 1.2 monoclonal antibodies but did not affect the enzymatic activities studied. This is the first evidence that ProT alpha affects Thy 1.2 expression in vitro.
...
PMID:Prothymosin alpha and factors from calf thymic cells decrease expression of Thy 1.2 antigen among small thymocytes from C57BL/6 mice. 779 93

To determine the effects of lipid accumulation on proteoglycan synthesis, we studied proteoglycan biosynthesis in rabbit aortic smooth muscle cells in culture. Cholesterol-enrichment was accomplished by incubating confluent smooth muscle cells with cationized low-density lipoprotein. Control and cholesterol-enriched cells were incubated with [35S]sulphate, [3H]glucosamine, or [3H]serine. Metabolically labelled proteoglycans in the cell layer and medium were quantified. During a 20 h incubation period, proteoglycan synthesis in cholesterol-enriched cells increased by 40-50% above that in control cells. A similar increase in precursor incorporation into proteoglycans was also noted following a short 15 min pulse. The cholesterol-enriched cells also showed a 45-50% increase over control rates in the intralysosomal accumulation of a large chondroitin sulphate proteoglycan and a small dermatan sulphate proteoglycan. The enhanced synthesis of proteoglycans in cholesterol-enriched cultures was inhibited by cycloheximide and actinomycin D, which are inhibitors of protein synthesis and transcription respectively. Proteoglycan turnover was investigated by pulse-chase analysis. Following a 2-h pulse, intracellular proteoglycans in cholesterol-enriched cells disappeared, having a half-life of 26.5 h compared with 2.8 h for those in the control cells. The amount of trypsin-releasable proteoglycan was significantly reduced in cholesterol-enriched cells. In addition, the degradation of proteoglycans was severely retarded in cholesterol-enriched cultures. The activities of three acid hydrolases, N-acetyl-beta-hexosaminidase, beta-glucuronidase and cathepsin C, were significantly reduced in cholesterol-enriched cells compared with activities in control cells. The results indicate that proteoglycan metabolism is altered in cholesterol-enriched smooth muscle cells.
...
PMID:Enhanced synthesis and accumulation of proteoglycans in cholesterol-enriched arterial smooth muscle cells. 837 76

Glycosomal phosphoglycerate kinase (gPGK) of Trypanosoma brucei differs from the cytoplasmic isozyme (cPGK) in its higher isoelectric point characterized by clusters of positive charges along the polypeptide chain, and a 20 amino acid C-terminal extension ending in serine-serine-leucine (SSL). While a C-terminal SSL tripeptide is apparently not capable of directing luciferase to the peroxisomes in mammalian cells [J. Cell Biol. 108 (1989), 1657-1664], we show here that it is sufficient for the import of luciferase as well as an unrelated protein, beta-glucuronidase, into the glycosomes of T. brucei, as determined by immunoelectron microscopy. The analysis of luciferase-gPGK fusion proteins indicates that the only targeting signal for import of gPGK into the glycosome resides in this C-terminal SSL sequence.
...
PMID:The C-terminal tripeptide of glycosomal phosphoglycerate kinase is both necessary and sufficient for import into the glycosomes of Trypanosoma brucei. 842 38

The pharmacodynamics of the non-steroidal anti-inflammatory drugs flunixin, tolfenamic acid and ketoprofen were studied in calves after intravenous administration. An acute inflammatory reaction was induced in tissue cages by the intracaveal injection of the mild irritant carrageenan, and the inhibition of inflammatory mediators and enzymes was investigated. The substances measured in the exudate included the enzymes (active and total metalloproteases, serine and cysteine proteases, acid phosphatase [AP], lactate dehydrogenase [LDH] and beta-glucuronidase) and the eicosanoids (prostaglandin [PG]E2 and leukotriene [LT]B4). Studies were also made of inhibition of the synthesis of serum thromboxane (Tx)B2 ex vivo, of bradykinin-induced oedema in vivo and of the generation of superoxide anions (O2-) in vitro. None of the drugs affected the concentration of LTB4, or the activities of metalloproteases, cysteine and serine proteases, AP or LDH in the exudate. All the drugs inhibited the synthesis of serum TxB2 and exudate PGE2 and inhibited the release of beta-glucuronidase. They also decreased the oedematous response to intradermally injected bradykinin and inhibited the generation of O2- ions by neutrophils in vitro. These actions may contribute to the anti-inflammatory effects of the drugs and hence to their clinical efficacy.
...
PMID:Comparative pharmacodynamics of flunixin, ketoprofen and tolfenamic acid in calves. 856 Jul 1

The four component proteins of the glycine decarboxylase multienzyme complex (the P-, H-, T-, and L-proteins) comprise over one-third of the soluble proteins in mitochondria isolated from the leaves of C3 plants. Together with serine hydroxymethyltransferase, glycine decarboxylase converts glycine to serine and is the site of photorespiratory CO2 and NH3 release. The component proteins of the complex are encoded on nuclear genes with N-terminal presequences that target them to the mitochondria. The isolated complex readily dissociates into its component proteins and reassociates into the intact complex in vitro. Because of the intimate association between photosynthesis and photorespiration, the proteins of the complex are present at higher levels in leaves in the light. The expression of these genes is controlled at the transcriptional level and the kinetics of expression are closely related to those of the small subunit of Rubisco. Deletion analysis of fusions between the promoter of the H-protein of the complex and the reporter gene beta-glucuronidase in transgenic tobacco has identified a region responsible for the tissue specificity and light dependence of gene expression. Gel shift experiments show that a nuclear protein in leaves binds to this region. Glycine decarboxylase has proven to be an excellent system for studying problems in plant biochemistry ranging from protein-protein interactions to control of gene expression.
...
PMID:Glycine decarboxylase: protein chemistry and molecular biology of the major protein in leaf mitochondria. 859 76

Two soybean cDNA clones, SPK-3 and SPK-4, encoding putative protein kinases were isolated and characterized. Both cDNAs encoded approximately 40-kDa serine/threonine kinases with unusual stretches of acidic amino acids in their carboxy-terminal regions, which are highly homologous to PKABA1 from wheat and ASKs from Arabidopsis. These kinases are encoded by one- or two-copy genes in the soybean genome. Notably, SPK-3 and -4 showed different patterns of expression in various soybean tissues. SPK-3 is highly expressed in dividing and elongating tissues of young seedlings but relatively weakly in tissues of mature plants. In contrast, SPK-4 showed relatively high and constitutive expression in all the tissues examined except for leaf tissues of mature plants. Although various stressors, such as dehydration and high salinity, increased the expression of both genes, the induction kinetics were different. The two genes also differed in their response to abscisic acid (ABA). SPK-3 was induced but SPK-4 was not affected by exogenously supplied abscisic acid. In accordance with these expression data analysis of the activity of a chimeric SPK-3 promoter::beta-glucuronidase (GUS) reporter gene by transient expression in tobacco leaves confirmed the inducibility of SPK-3 by salt and ABA. Polyclonal antibodies raised against a recombinant SPK-4 protein produced in Escherichia coli specifically recognized both recombinant SPK-3 and -4 proteins. Kinase assays using affinity-purified SPK-4/ antibody complexes with crude soybean extracts as substrate identified specific phosphorylation of two 41 and 170 kDa soybean proteins that were phosphorylated on serine residues. Taken together, our results suggest that SPK-3, and/or SPK-4 are functional serine protein kinase(s). Furthermore, SPK-3 and -4 may play different roles in the transduction of various environmental stresses.
...
PMID:Differential expression of two functional serine/threonine protein kinases from soybean that have an unusual acidic domain at the carboxy terminus. 926 31

Two pathways have been implicated in the regulation of maize ferritin synthesis in response to iron. One of them involves the plant hormone abscisic acid (ABA) and controls the expression of ZmFer2 gene(s). Another pathway, ABA-independent, has been characterized in a de-rooted maize plantlet system and involves an oxidative step. The ZmFer1 maize ferritin gene is not regulated by ABA, and it is shown in this paper that the corresponding mRNA accumulates in de-rooted maize plantlets and BMS (Black Mexican Sweet) maize cell suspension cultures in response to iron via the oxidative pathway described previously. To investigate ZmFer1 gene regulation further, the BMS cell system has been used to develop a transient expression assay using a ZmFer1-beta-glucuronidase fusion. Both iron induction and antioxidant inhibition of ZmFer1 gene expression were observed in this system. Using Northern blot analysis and transient expression experiments, it was shown that both okadaic acid and calyculin A, two serine/ threonine phosphatase inhibitors, specifically inhibit ZmFer1 gene expression. These data indicate that an okadaic acid-sensitive protein phosphatase activity is involved in the regulation of the ZmFer1 ferritin gene in maize cells, and this activity is required for iron-induced expression of this gene.
...
PMID:Inhibition of the iron-induced ZmFer1 maize ferritin gene expression by antioxidants and serine/threonine phosphatase inhibitors. 940 24

Three random translational beta-glucuronidase (gus) gene fusions were previously obtained in Arabidopsis thaliana, using Agrobacterium-mediated transfer of a gus coding sequence without promoter and ATG initiation site. These were analysed by IPCR amplification of the sequence upstream of gus and nucleotide sequence analysis. In one instance, the gus sequence was fused, in inverse orientation, to the nos promoter sequence of a truncated tandem T-DNA copy and translated from a spurious ATG in this sequence. In the second transgenic line, the gus gene was fused to A. thaliana DNA, 27 bp downstream an ATG. In this line, a large deletion occurred at the target site of the T-DNA. In the third line, gus is fused in frame to a plant DNA sequence after the eighth codon of an open reading frame encoding a protein of 619 amino acids. This protein has significant homology with animal and plant (receptor) serine/threonine protein kinases. The twelve subdomains essential for kinase activity are conserved. The presence of a potential signal peptide and a membrane-spanning domain suggests that it may be a receptor kinase. These data confirm that plant genes can be tagged as functional translational gene fusions.
...
PMID:Analysis of T-DNA-mediated translational beta-glucuronidase gene fusions. 948 33

Biomarkers of periodontal disease activity may be obtained from potential proteolytic and hydrolytic enzymes of inflammatory cell origin. Studies that have sought to correlate these enzymes with periodontal disease activity are reviewed with special consideration given to collagenases, cysteine, aspartate and serine proteinases, beta-glucuronidase, arylsulphate, alkaline and acid phosphatases, myeloperoxidase, lysozyme and lactoferrin.
...
PMID:Advances in periodontal diagnosis. 7. Proteolytic and hydrolytic enzymes link with periodontitis. 959 84


<< Previous 1 2 3 4 5 Next >>