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)

In higher plants, a cis-acting element, DRE/CRT, is involved in gene expression responsive to drought and low-temperature stress. To understand signal transduction pathways from the cold stress signal to gene expression, we characterized a gene family for DRE/CRT-binding proteins DREB1A and CBF1 in Arabidopsis thaliana. DREB1A and CBF1 were shown to be involved in low-temperature-responsive gene expression. We screened an Arabidopsis genomic DNA library with the cDNA fragment of DREB1A as a probe and isolated DREB1A and 2 related genes, DREB1B (= CBF1) and DREB1C. These were arrayed in the order B, A, C in an 8.7 kb region of Arabidopsis chromosome 4. Northern blot analysis using gene-specific probes showed that the 3 DREB1 genes are induced mainly by cold stress but not by osmotic stress in leaves, roots, and stems. Several conserved sequences were found in the promoter regions of all 3 genes. The beta-glucuronidase (GUS) reporter gene driven by the DREB1 promoters was induced at transcriptional level by low temperature in transgenic Arabidopsis plants.
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PMID:An Arabidopsis gene family encoding DRE/CRT binding proteins involved in low-temperature-responsive gene expression. 973 50

We had previously identified the MYBC1 gene, which encodes a single-repeat R3-MYB protein, as a putative osmotic responding gene; however, no R3-MYB transcription factor has been reported to regulate osmotic stress tolerance. Thus, we sought to elucidate the function of MYBC1 in response to osmotic stresses. Real-time RT-PCR analysis indicated that MYBC1 expression responded to cold, dehydration, salinity and exogenous ABA at the transcript level. mybc1 mutants exhibited an increased tolerance to freezing stress, whereas 35S::MYBC1 transgenic plants exhibited decreased cold tolerance. Transcript levels of some cold-responsive genes, including CBF/DREB genes, KIN1, ADC1, ADC2 and ZAT12, though, were not altered in the mybc1 mutants or the 35S::MYBC1 transgenic plants in response to cold stress, as compared to the wild type. Microarray analysis results that are publically available were investigated and found transcript level of MYBC1 was not altered by overexpression of CBF1, CBF2, and CBF3, suggesting that MYBC1 is not down regulated by these CBF family members. Together, these results suggested that MYBC1is capable of negatively regulating the freezing tolerance of Arabidopsis in the CBF-independent pathway. In transgenic Arabidopsis carrying an MYBC1 promoter driven beta-glucuronidase (GUS) construct, GUS activity was observed in all tissues and was relatively stronger in the vascular tissues. Fused MYBC1 and GFP protein revealed that MYBC1 was localized exclusively in the nuclear compartment.
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PMID:A single-repeat R3-MYB transcription factor MYBC1 negatively regulates freezing tolerance in Arabidopsis. 2033 73