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)

ACC (1-aminocyclopropane-1-carboxylate) oxidase genes are differentially expressed in melon during development and in response to various stresses. We investigated the molecular basis of their transcription by analyzing the 5' untranslated regions of the ACC oxidase genes CM-ACO1 and CM-ACO3. In order to determine how their temporal and spatial expression patterns were established, we fused the promoter regions of CM-ACO1 (726 bp) and CM-ACO3 (2260 bp) to the beta-glucuronidase (GUS) reporter gene and examined their regulation in transgenic tobacco plants. The CM-ACO1 promoter was able to drive GUS expression in response to wounding, and to treatment with ethylene or copper sulfate. It was also rapidly induced (8-12 h postinoculation) in tobacco leaves inoculated with the hypersensitive response (HR)-inducing bacterium Ralstonia solanacearum. Expression was also observed during compatible interactions but was delayed. In contrast, the CM-ACO3 promoter was not expressed in response to infection, but was up-regulated during flower development. Both promoters were regulated during leaf senescence but in different patterns. The CM-ACO1-driven GUS activity increased sharply concomitantly with the onset of chlorophyll breakdown, while the CM-ACO3 promoter drove strong GUS expression in green, fully expanded leaves and this declined at the onset of senescence. This result is consistent with the expression patterns of these two genes in senescent melon leaves. These data suggest that the regulation of expression of CM-ACO1 is related preferentially to stress responses, whereas CM-ACO3 seems to be associated with developmental processes. The possible role of ethylene is discussed, particularly in the regulation of the CM-ACO1 gene in response to stress and during senescence.
Mol Gen Genet 1997 Oct
PMID:Differential activation of two ACC oxidase gene promoters from melon during plant development and in response to pathogen attack. 939 45

Developmental control of the formation of the serrated margin of leaf blades was investigated. First, the expression was characterized of a marker gene encoding beta-glucuronidase in strain #1-35-38, a transgenic strain of Arabidopsis thaliana (L.) Heynh, derived by the use of a previously described transposon-tagging system. In strain #1-35-38, expression of the marker gene was tissue-specific, being restricted to stipules and the toothed margins of laminae. Using this transgenic marker gene, we examined the development of leaf blade margins in Arabidopsis. We compared the pattern of expression of the marker gene in the leaves of the wild-type plant with that in plants carrying the asymmetric leaves1 (as1) mutation, which causes dramatic changes in leaf-blade morphology in Arabidopsis. The as1 mutant showed normal morphology of early leaf primordia. The mutation affected the development of leaf segmentation in Arabidopsis without any change in the number or morphology of cells in laminae. The as1 mutation affected leaf morphology independently of mutations in other genes known to affect leaf morphogenesis, such as the acaulis1 mutation and the angustifolia mutation. Based upon these results, the development of the morphology of leaf margins in Arabidopsis is discussed.
Mol Gen Genet 1997 Oct
PMID:Genetic analyses of the formation of the serrated margin of leaf blades in Arabidopsis: combination of a mutational analysis of leaf morphogenesis with the characterization of a specific marker gene expressed in hydathodes and stipules. 939 47

A gene that is homologous to the vp1 genes from maize and rice, the Arabidopsis abi3 gene and PvAlf from Phaseolus vulgaris was isolated from the resurrection plant, Craterostigma plantagineum Hochst, The C. plantagineum gene (epvp1) encodes a protein of 688 amino acids and contains five introns at positions identical to those in the Arabidopsis, maize and rice homologues. The cpvp1 transcript is present in mature seeds and in young seedlings up to 8 days following germination. The ability of the cpvp1 gene product to activate target genes was demonstrated by transient expression experiments in tobacco protoplasts using reporter gene constructs containing the beta-glucuronidase (GUS) gene fused to the promoter of two late embryogenesis abundant (LEA)-like genes, CDeT27-45 and CDeT6-19 from C. plantagineum, or the promoter of a maize gene encoding a 22-kDa zein seed storage protein.
Mol Gen Genet 1997 Nov
PMID:Structure and function of the vp1 gene homologue from the resurrection plant Craterostigma plantagineum Hochst. 941 38

Agroinfiltration--the infiltration of Agrobacterium tumefaciens into intact plant levels--provides a rapid and simple way of screening large numbers of transgene constructs for silencing in response to a resident transgene. Transgenic Nicotiana sylvestris plants homozygous for the tobacco class I chitinase A gene CHN48 under the control of the cauliflower mosaic virus 35S RNA promoter (P35S) show a high incidence of postranscriptional gene silencing. We forced suspensions of A. tumefaciens, carrying P35S-CHN48 in a binary Tiplasmid vector, into wild-type and transgenic N, sylvestris leaves with a blunt-tipped plastic syringe. The infiltrated CHN48 transgene was expressed in leaves transformed with the vector alone, but not in CHN48-transformed leaves showing the silent phenotype. In contrast, expression of a chimeric P35S-E. coli beta-glucuronidase gene (uidA) infiltrated into leaves was not affected by the presence of the CHN48 transgene stably integrated in the host genome. These results show that extra copies of CHN48 are silenced by resident, silent copies of the same gene and confirm that CHN48 silencing is not the result of promoter interactions. The results also suggest that silencing of the additional CHN48 copies does not require their integration into chromosomes.
Mol Gen Genet 1997 Nov
PMID:Silencing of transgenes introduced into leaves by agroinfiltration: a simple, rapid method for investigating sequence requirements for gene silencing. 941 43

Potato plants carrying the Ry(sto) gene from Solanum stoloniferum are extremely resistant to a number of potyviruses, but it is not known at what stage of infection the resistance is expressed. The resistance may be due to Ry(sto) or to a closely linked gene. In this investigation, we used potato virus Y (PVY) and a tobacco etch virus construct that encodes beta-glucuronidase (TEV-GUS) to monitor virus infections of potato plants. Systemic spread of either virus in resistant potato plants was not detectable by serology, RT-PCR, GUS assay or bioassay although each replicated in the initially infected cells of leaves from resistant potato cultivars and was transported into neighbouring cells. However, 3 days post-inoculation (p.i.) a necrotic reaction set in that stopped movement and accumulation of both viruses by 7 days p.i. The resistance reaction (probably a hypersensitive reaction) became visible as necrotic streaks on veins on the lower leaflet surfaces of some potato cultivars carrying the Ry(sto) gene and may be elicited by a common potyviral gene product.
J Gen Virol 1998 Jan
PMID:A hypersensitive response-like mechanism is involved in resistance of potato plants bearing the Ry(sto) gene to the potyviruses potato virus Y and tobacco etch virus. 946 Sep 39

1. The effect of taxol on selected lysosomal enzymes (cathepsin D, lysosomal lipase, beta-glucuronidase, beta-glucosidase, alanine aminopeptidase) in mouse hepatocytes after 24-hr treatment by increasing doses (0.75 mg/kg bw, 1.25 mg/kg bw and 2.5 mg/kg bw) was studied. 2. The segments were also taken from the mice for ultrastructural studies with the use of electron microscopy. The greatest changes in activity of enzymes at the taxol dose of 2.5 mg/kg bw were as follows: the activity of cathepsin D increased by 71%, that of alanine aminopeptidase increased by 103%, that of beta-glucuronidase decreased by 45% and that of beta-glucosidase decreased by 63%. 3. The significant changes observed in the hepatocyte ultrastructure were closely correlated with biochemical changes that were dependent on the taxol dosage.
Gen Pharmacol 1998 Feb
PMID:Activity of lysosomal system in mouse liver after taxol administration. 950 80

Asr is a family of genes that maps to chromosome 4 of tomato. Asr2, a recently reported member of this family, is believed to be regulated by abscisic acid (ABA), stress and ripening. A genomic Asr2 clone has been fully sequenced, and candidate upstream regulatory elements have been identified. To prove that the promoter region is functional in vivo, we fused it upstream of the beta-glucuronidase (GUS) reporter gene. The resulting chimeric gene fusion was used for transient expression assays in papaya embryogenic calli and leaves. In addition, the same construct was used to produce transgenic tomato, papaya, tobacco, and potato plants. Asr2 upstream sequences showed promoter function in all of these systems. Under the experimental conditions tested, ABA stimulated GUS expression in papaya and tobacco, but not in tomato and potato systems.
Mol Gen Genet 1998 Apr
PMID:Analysis of an abscisic acid (ABA)-responsive gene promoter belonging to the Asr gene family from tomato in homologous and heterologous systems. 961 66

During replication in its host plant, coconut foliar decay virus (CFDV) remains restricted to the phloem tissue. Previous in vivo studies on subgenomic CFDV DNA had provided evidence for the phloem specificity of the CFDV promoter. Here, new promoter constructs are described which are distinguished by the presence or absence of various cis-acting signals and which gave rise to a 16-fold higher reporter gene (beta-glucuronidase) activity (reaching 30% of the cauliflower mosaic virus 35S promoter) in tobacco protoplasts, while the phloem specificity in transgenic tobacco plants was conserved. Surprisingly, the CFDV stem-loop structure dramatically influenced transcriptional efficiency. From these studies and sequence comparisons with other phloem-specific promoters, cis-signals involved in CFDV promoter strength and tissue specificity were identified.
J Gen Virol 1998 Jun
PMID:Characterization of cis-acting elements affecting strength and phloem specificity of the coconut foliar decay virus promoter. 963 93

Organisms synthesize heat shock proteins (HSPs) in response to sublethal heat stress and concomitantly acquire increased tolerance against a subsequent, otherwise lethal, heat shock. Heat shock factor (HSF) is essential for the transcription of many HSP genes. We report the isolation of two HSF genes, HSF3 and HSF4, from an Arabidopsis cDNA library. Transgenic Arabidopsis plants were generated containing constructs that allow expression of HSF3 and HSF4 or the respective translational beta-glucuronidase (GUS) fusions. Overexpression of HSF3 or HSF3-GUS, but not of HSF4 or HSF4-GUS, causes HSP synthesis at the non-heat-shock temperature of 25 degrees C in transgenic Arabidopsis. In transgenic plants bearing HSF3/HSF3-GUS, transcription of several heat shock genes is derepressed. Electrophoretic mobility shift assays suggest that derepression of the heat shock response is mediated by HSF3/HSF3-GUS functioning as transcription factor. HSF3/HSF3-GUS-overexpressing Arabidopsis plants show an increase in basal thermotolerance, indicating the importance of HSFs and HSF-regulated genes as determinants of thermoprotective processes. Plants transgenic for HSF3/HSF3-GUS exhibit no other obvious phenotypic alterations. Derepression of HSF activity upon overexpression suggests the titration of a negative regulator of HSF3 or an intrinsic constitutive activity of HSF3. We assume that stable overexpression of HSFs may be applied to other organisms as a means of derepressing the heat shock response.
Mol Gen Genet 1998 May
PMID:HSF3, a new heat shock factor from Arabidopsis thaliana, derepresses the heat shock response and confers thermotolerance when overexpressed in transgenic plants. 964 33

Promoter regions associated with each of the six ssDNA components of banana bunchy top virus (BBTV) have been characterized. DNA segments incorporating the intergenic regions of BBTV DNA-1 to -6 were isolated and fused to the uidA (beta-glucuronidase) reporter gene to assess promoter activity. In tobacco cell suspensions, the BBTV DNA-2 and -6 promoters generated levels of GUS expression 2-fold greater and similar to the 800 bp CaMV 35S promoter, respectively. Deletion analysis of the BBTV DNA-6 promoter suggested all the necessary promoter elements required for strong expression were located within 239 nucleotides upstream of the translational start codon. In transgenic tobacco plants, the BBTV-derived promoters generally provided a weak, tissue-specific GUS expression pattern restricted to phloem-associated cells. However, in callus derived from tobacco leaf tissue, GUS expression directed by the BBTV DNA-6 promoter was strong and, in some lines, comparable to the CaMV 35S promoter. Detectable promoter activity associated with the BBTV promoters in banana embryogenic cells was only observed using a sensitive green fluorescent protein (GFP) reporter. Promoters derived from BBTV DNA-4 and -5 generated the highest levels of transient activity, which were greater than that of the maize ubi-1 promoter. In transgenic banana plants, the activity of the BBTV DNA-6 promoter was restricted to the phloem of leaves and roots, stomata and root meristems.
J Gen Virol 1998 Oct
PMID:Promoter activity associated with the intergenic regions of banana bunchy top virus DNA-1 to -6 in transgenic tobacco and banana cells. 978 33


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