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)

The 5' upstream region of the rice storage protein type II glutelin gene was examined for its regulatory function in transgenic tobacco. Chimeric genes containing 5' flanking regions of the glutelin gene transcriptionally fused to the beta-glucuronidase (GUS) reporter gene were introduced into the tobacco genome by Agrobacterium tumefaciens-mediated gene transfer. The chimeric genes were expressed specifically in developing seeds, as opposed to leaves and stems, of the transgenic tobacco. Histochemical analysis revealed that the GUS activity was restricted to the endosperm tissue. A deletion series of the 5' flanking region was created from position -1329 to -74 relative to the transcriptional initiation site and similarly examined in transgenic tobacco. Measurement of GUS activity of the seeds from the transgenic plants bearing the chimeric genes indicated that the region between positions -441 and -237 was required for the temporal and endosperm-specific expression of the GUS activity in tobacco. RNA analysis by northern blotting confirmed the importance of the -441 to -237 region. Addition of up to 888 bp to the -441 deletion resulted in little increase in GUS activity, although all constructs expressing the GUS gene showed a similar tissue and temporal regulation pattern.
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PMID:Analysis of the 5' flanking region responsible for the endosperm-specific expression of a rice glutelin chimeric gene in transgenic tobacco. 188 96

A vector has been designed that contains a truncated CaMV (cauliflower mosaic virus) 35S promoter fused to a receptor gene encoding beta-glucuronidase (GUS), placed adjacent to the left border sequence of an Agrobacterium vector. In potato plants transformed with this vector, different patterns of transcription were detected at high frequency using in situ assays for GUS activity. Previous studies in Drosophila using analogous vectors have shown that the new patterns of transcription in many cases reflect the patterns of expression of genes adjacent to the site of vector insertion. If this is also the case in plants, the vector described here will be useful in identifying the activity of genes in different cell types and will assist in determining their function.
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PMID:New patterns of gene activity in plants detected using an Agrobacterium vector. 189

A 1420 bp genomic fragment (lambda-hor1-17) encompassing a Hor-1 gene encoding a C-hordein polypeptide is presented. The deduced amino acid sequence is 261 residues long. It comprises a 20 amino acid signal peptide, unique NH2- and COOH-terminal regions and a coding region comprised of pentapeptide (PQQPY) and octapeptide (PQQPFPQQ) repeat motifs. The 431 bp of 5' non-coding region contains a 'TATA box' at -105, a 'CACA box' (-181 to -201) and a -300 prolamin element. In the 3' non-coding region there are two putative polyadenylation signals located 88 and 142 bp downstream of the stop codon. The structure of lambda-hor1-17 is compared with that of another gene (lambda-hor1-14) encoding a C-hordein polypeptide, which contains an amber codon interrupting the ORF. A functional assay in which the 5' non-coding regions of the two genes were fused to the beta-glucuronidase (GUS) gene demonstrated that both genes were transcriptionally active and that circa 430 bp of the C-hordein promoters were sufficient to drive the expression of the GUS gene in developing barley endosperms. It also demonstrated that both promoters had transcriptional efficiencies comparable with that of the 35S CaMV promoter. The in vitro translation of the coding region of lambda-hor1-14 in the wheat germ system showed that the premature stop codon could be partially suppressed. The suppression was also demonstrated in a transient expression assay in vivo using isolated barley endosperms.
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PMID:Amber codon suppression: the in vivo and in vitro analysis of two C-hordein genes from barley. 193 95

In comparison with animals, relatively few plant genes have been identified that have been shown to be under organ-, tissue- or cell-type-specific regulation. In this paper, we describe how the beta-glucuronidase (GUS) reporter gene (gusA or uidA), fused to a weak promoter (a truncated (-90 bp) CaMV35S promoter), can be used to identify tissue-specific markers in transgenic tobacco plants. The rationale was that the expression of gusA would be determined primarily by position effect. Quantitative analysis revealed that, of 184 -90-gus transgenic plants, 73% exhibited gusA gene activation in leaf tissue, and the level of GUS enzyme activity varied over a 300-fold range within the population. In comparison, transformation with a promoterless gusA gene resulted in GUS expression in 78% of all plants analyzed (in leaf and/or root) and expression levels were three-fold or more lower. Qualitative GUS analysis of single locus -90-gus transformants revealed differential expression in diverse tissues. The spatial pattern of GUS activity was unique to individual transformants, was a reflection of differential gusA gene transcription, and was stably transmissible to progeny. Evidence for preferential expression in roots not only of the -90-gus, but also the promoterless gusA gene is presented. The value of the -90 bp promoter-gusA sequence, which is termed an 'interposon', as a tool both to identify native enhancer sequences in situ and to investigate position effects in plants, is discussed.
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PMID:Functional tagging of regulatory elements in the plant genome. 193 94

The S locus glycoprotein (SLG) gene of Brassica encodes stigmatic glycoproteins that are implicated in the pollen-stigma interaction of self-incompatibility. We have transformed the related plant Arabidopsis thaliana with a chimaeric gene consisting of the promoter region of an SLG gene fused to the reporter gene beta-glucuronidase (GUS). In transgenic plants the gene was expressed in two cell types of the flower. In stigmas, the timing and distribution of GUS activity was similar to that previously described for SLG expression in Brassica. In anthers, expression was detected at an earlier stage of flower development with GUS activity restricted to the tapetal cell layer. The novel finding of SLG-promoter activity in the anther supports the hypothesis that sporophytic control of self-incompatibility is a result of SLG-gene expression in the tapetum.
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PMID:A Brassica S locus gene promoter directs sporophytic expression in the anther tapetum of transgenic Arabidopsis. 199 65

We have previously isolated a legumin gene LeB4 from Vicia faba and shown that a 4.7 kb DNA fragment containing the gene leads to seed-specific expression in transgenic tobacco plants. Here we report that the 2.4 kb upstream sequence alone, when fused to either the neomycin phosphotransferase II (nptII) gene or the beta-glucuronidase (uidA) gene, leads to high enzyme levels in transgenic seeds of both tobacco and Arabidopsis. beta-Glucuronidase (GUS) activity is especially intense in the cotyledons fading out towards the embryonal root tip, a result confirmed by in situ hybridization. Staining of endosperm cells is consistent in both species. Analysis of a series of promoter deletion mutants fused to the nptII gene and introduced into tobacco plants revealed that about 1 kb of 5'-flanking sequence is sufficient for high-level expression but indirect evidence suggests the presence of weak positive regulatory elements further upstream. Deletions leaving only 0.2 kb of upstream sequence reduce enzyme levels to less than 10%. A deletion which destroys the legumin box with its seed protein gene-specific CATGCATG motif has no obvious effects on expression levels.
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PMID:Upstream sequences regulating legumin gene expression in heterologous transgenic plants. 200 85

The transit peptide of the maize waxy protein (a nuclear-encoded amyloplast protein of the maize endosperm) was studied with respect to its role in subcellular protein targeting in transgenic potato plants. TP30, a chimeric precursor protein consisting of the waxy transit peptide and an additional 34 amino acids of the mature waxy protein fused to the beta-glucuronidase of Escherichia coli, was expressed in potato plants under the control of the 35S promoter of cauliflower mosaic virus. This fusion protein is imported not only into amyloplasts, the natural target organelles in the maize plant, but also into chloroplasts. In contrast, Gus, the beta-glucuronidase alone, which was also expressed in parallel experiments in transgenic potato plants is always found in the cytosol of the plant cells. As a consequence of the different subcellular locations of TP30 and Gus, we observed differences in the expression rates of the respective proteins in leaf cells, resulting in higher steady state levels of TP30 compared to Gus. In tuber cells, no correlation between intracellular location and expression of the proteins was found.
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PMID:Subcellular location and expression level of a chimeric protein consisting of the maize waxy transit peptide and the beta-glucuronidase of Escherichia coli in transgenic potato plants. 200 71

Phagosomes are membrane-bound vesicles, formed by the receptor-mediated internalization of particulate ligands, which exchange soluble and membrane proteins with other endocytic compartments as a part of their maturation process. This exchange of material is undoubtedly mediated by fusion of phagosomes with other membrane-bound compartments of the endocytic pathway. By using a particulate probe (fixed Staphylococcus aureus coated with mouse anti-dinitrophenol monoclonal antibody) localized in phagosomes and a soluble probe (dinitrophenol-derivitized beta-glucuronidase) internalized by receptor-mediated endocytosis, we have studied phagosome-endosome and phagosome-lysosome fusion in intact cells and in a cell-free system. Vesicle fusion was assessed by measuring beta-glucuronidase activity associated with S. aureus particles after lysis of the membranes. In intact macrophages, newly formed phagosomes fused with early endosomes and with lysosomes. Fusion with lysosomes was observed to commence after a short lag period of about 5 min. In broken-cell preparations, phagosomes were able to fuse with early endosomes. It was not possible to reconstitute phagosome-lysosome fusion in vitro. In vitro phagosome-endosome fusion required energy and cytosolic- and membrane-associated proteins. A nonhydrolyzable analog of GTP stimulated fusion at low cytosol concentrations and inhibited fusion at high cytosol concentrations. These observations indicate that the mechanisms mediating phagosome-endosome fusion are similar to those described for endosome-endosome fusion. Our results suggest that exchange of material with endosomes is an important step in the process of phagosome maturation.
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PMID:Fusion of newly formed phagosomes with endosomes in intact cells and in a cell-free system. 200

To establish a genetic system for dissection of light-mediated signal transduction in plants, we analyzed the light wavelengths and promoter sequences responsible for the light-induced expression of the Arabidopsis thaliana chalcone synthase (CHS) promoter fused to the beta-glucuronidase (GUS) marker gene. Transgenic A. thaliana lines carrying 1975, 523, 186, and 17 bp of the CHS promoter fused to the GUS gene were generated, and the expression of these chimeric genes was monitored in response to high intensity light in mature plants and to different wavelengths of light in seedlings. Fusion constructs containing 1975 and 523 bp of CHS promoter sequence behaved identically to the endogenous CHS gene under all conditions. Expression of these constructs was induced specifically in response to high intensity white light and blue light. The response to blue light was seen in the presence of the Pfr form of phytochrome. Fusion constructs containing 186 bp of promoter sequence showed reduced basal levels of expression and only weak stimulation by blue light but were induced significantly by high intensity white light. These analyses showed that the expression of the A. thaliana CHS gene is responsive to a specific blue light receptor and that sequences between -523 and -186 bp are required for optimal basal and blue light-induced expression of this gene. The experiments lay the foundation for a simple genetic screen for light response mutants.
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PMID:High intensity and blue light regulated expression of chimeric chalcone synthase genes in transgenic Arabidopsis thaliana plants. 203 7

We have isolated and analyzed a pre-ferredoxin gene from Arabidopsis thaliana. This gene encodes a 148 amino acid precursor protein including a chloroplast transit peptide of 52 residues. Southern analysis shows the presence of a single copy of this ferredoxin (Fd) gene in the A. thaliana genome. Its expression is tissue-specific and positively affected by light. Response times, both to dark and light conditions, are remarkably rapid. A chimeric gene consisting of a 1.2 kb Fd promoter fragment fused to the beta-glucuronidase reporter gene was transferred to tobacco. This fusion gene is expressed in a tissue-specific way; it shows high levels of expression in green leaves, as compared to root tissue.
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PMID:Tissue-specific expression directed by an Arabidopsis thaliana pre-ferredoxin promoter in transgenic tobacco plants. 210 30


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