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)

Phenylalanine ammonia-lyase (PAL) is encoded by a small family of genes in Arabidopsis. We cloned and partially characterized one of these genes, PAL1. The deduced amino acid sequence is highly similar to PAL from bean, parsley, and rice. The promoter contains sequence elements homologous to two putative regulatory elements conserved among several phenylpropanoid genes. The regulation of the PAL1 gene was examined by analysis of beta-glucuronidase (GUS) activity in transgenic Arabidopsis containing PAL1-GUS gene fusions. The PAL1 promoter was activated early in seedling development and in adult plants was strongly expressed in the vascular tissues of roots and leaves, but was not active in the root tip or the shoot apical meristem. In flowers, expression was observed in sepals, anthers, and carpels, but not in petals. Transcripts encoded by the endogenous PAL genes and GUS transcripts from the PAL1-GUS gene fusion were induced by wounding, HgCl2-stress, and light. Analysis of the regulatory properties of 5' deleted promoters showed that the proximal region of the promoter to -290 was sufficient to establish the full tissue-specific pattern of expression and that the proximal region to -540 was responsive to environmental stimuli. Negative and positive elements were located between -1816 and -823 and between -823 and -290, respectively.
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PMID:Functional properties of a phenylalanine ammonia-lyase promoter from Arabidopsis. 215 31

Phenylalanine ammonia-lyase (PAL) catalyses the first step in the biosynthesis of phenylpropanoids, which form a wide variety of plant secondary products. The transcription of PAL is regulated in response to various factors that induce the accumulation of flavonoids, lignin and compounds thought to be involved in plant defence reactions. The 5' upstream sequence of a PAL gene from Phaseolus vulgaris was fused to the coding region of the reporter gene encoding beta-glucuronidase (GUS), and transformed into potato and tobacco plants. Histochemical analysis of GUS expression showed that the PAL promoter was active in specific cell types that accumulated phenylpropanoid derivatives in response to mechanical wounding, and also during normal development of the xylem and flower. In xylem that had undergone secondary thickening, GUS activity occurred in rays of cells thought to be the xylem parenchyma. It was postulated that PAL activity in these cells could provide intermediates for lignin synthesis in xylem vessels that had terminally differentiated.
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PMID:Tissue- and cell-specific activity of a phenylalanine ammonia-lyase promoter in transgenic plants. 279 72

Phenylalanine ammonia-lyase (PAL) catalyses the first committed step in the biosynthesis of phenylpropanoids, which perform a variety of functions in plant development and in their interactions with the environment. French bean contains a small family of genes encoding PAL and two of these genes, PAL2 and PAL3, have been shown to be differentially expressed at the mRNA level in bean tissues. The transcriptional activities of the PAL2 and PAL3 genes have been investigated by fusing their promoters to the reporter gene beta-glucuronidase (GUS) and transforming these constructs into Arabidopsis, potato and tobacco. The PAL2- and PAL3-GUS constructs exhibited different spatial and temporal patterns of expression during development and in response to environmental stimuli. The consistency of these data with previous mRNA analysis in bean suggests that the differential expression of these two PAL genes is, at least in part, a function of their promoter activities. New patterns of PAL2 and PAL3 promoter activities were also characterized. Some species-specific differences in GUS expression were observed and these may reflect differences in phenylpropanoid metabolism or the signals that modulate PAL gene transcription.
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PMID:Transcription of two members of a gene family encoding phenylalanine ammonia-lyase leads to remarkably different cell specificities and induction patterns. 840 14

Phenylalanine ammonia-lyase (PAL) genomic sequences were isolated from a rice (Oryza sativa L.) genomic library using a PCR-amplified rice PAL DNA fragment as a probe. There is a small family of PAL genes in the rice genome. The nucleotide sequence of one PAL gene, ZB8, was determined. The ZB8 gene is 4660 bp in length and consists of two exons and one intron. It encodes a polypeptide of 710 amino acids. The transcription start site was 137 bp upstream from the translation initiation site. Rice PAL transcripts accumulated to a high level in stems, with lower levels in roots and leaves. Wounding of leaf tissues induced ZB8 PAL transcripts to a high level. In rice suspension-cultured cells treated with fungal cell wall elicitors, the ZB8 PAL transcript increased within 30 min and reached maximum levels in 1-2 h. The transcription of the ZB8 gene was investigated by fusing its promoter to the reporter gene beta-glucuronidase (GUS) and transforming the construct into rice and tobacco plants, as well as rice suspension-cultured cells. High levels of GUS activity were observed in stems, moderate levels in roots and low levels in leaves of transgenic rice and tobacco plants. Histochemical analysis indicated that in transgenic rice the promoter was active in root apical tips, lateral root initiation sites, and vascular and epidermal tissues of stems and roots. In rice flowers, high GUS activity was observed in floral shoots, receptacles, anthers and filaments, occasionally GUS activity was also detected in lemma and awn tissues. In tobacco flowers, high GUS activity was detected in the pink part of petals. Consistent with the activity of endogenous PAL transcripts, wounding of rice and tobacco leaf tissues induced GUS activity from low basal levels. Tobacco mosaic virus (TMV) infection of tobacco leaves induced GUS activity to a high level. Fungal cell wall elicitors strongly induced GUS activity and GUS transcripts to high levels in transgenic rice suspension-cultured cells. We demonstrated that the promoter of ZB8 gene is both developmentally regulated and stress-inducible.
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PMID:Cloning and properties of a rice gene encoding phenylalanine ammonia-lyase. 853 51