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)

Ligatin, a receptor that recognizes phosphorylated sugars, was isolated from plasma membranes of mouse macrophages, rat ileum, and rat brain. Several acidic hydrolases including N-acetyl beta-D-glucosaminidase (beta-NAG) were solubilized with this receptor. The solubilized beta-NAG bound to ligatin in vitro as demonstrated by affinity chromatography using the immobilized receptor. beta-N-Acetyl D-glucosaminidase-ligatin complexes were dissociated by low concentrations of mannose 6-phosphate (Man6P) and/or glucose 1-phosphate (Glc 1P). The effectiveness of these two phosphomonosaccharides varied depending on the source of the enzyme: ileal beta-NAG-ligatin complexes showed a four-fold preferential dissociation with Man6P; macrophage complexes showed a 160-fold preferential dissociation with Glc 1P. Brain complexes dissociated with nearly equal preference for Man6P and Glc 1P. Heterologous complexes displayed the specificity characteristic of the source of the enzyme regardless of the source of the ligatin. Treatment of the solubilized hydrolases with endoglucosaminidase H released phosphorous-32 label from these enzymes and prevented binding of beta-NAG to ligatin. However, treatment of the solubilized hydrolases with alkaline phosphatase reduced the binding of beta-NAG to ligatin by no more than 30%. This apparent resistance of beta-NAG to dephosphorylation was consistent with the chromatographic behavior of QAE of 3H-labeled acidic oligosaccharides isolated from the solubilized hydrolases. The oligosaccharides that contain phosphorylated hexose were less acidic than phosphomonoesters and were insensitive to alkaline phosphatase until subjected to acid hydrolysis. These results suggested the presence of a phosphodiester on beta-NAG analogous to the NAC glucosamine 1 P6 mannose present on beta-glucuronidase isolated from mouse lymphoma cells (Tabas I, Kornfield, S: J Biol Chem 255: 6633, 1980).
 ...
PMID:Ligatin binds phosphohexose residues on acidic hydrolases. 729 41

Numerous, highly conserved RING-H2 domains are found in the model plant Arabidopsis thaliana (thale cress). To characterize potential RING-H2 protein interactions, the small RING-H2 protein RHA2a was used as bait in a yeast two-hybrid screen. RHA2a interacted with one of the plant-specific NAC [NAM ('no apical meristem'), ATAF1/2, CUC2 ('cup-shaped cotyledons 2')] transcription factors, here named ANAC (abscisic acid-responsive NAC). The core RING-H2 domain was sufficient for the interaction. The ability of 11 structurally diverse RING-H2 domains to interact with ANAC was then examined. Robust interaction was detected for three of the domains, suggesting multi-specificity for the interaction. The domains that interacted with ANAC contain a glutamic acid residue in a position corresponding to a proline in many RING-H2 domains. Conversion of this glutamic acid residue into proline in RHA2a decreased its ability to interact with ANAC, most likely by changing the interaction surface. This suggested that a short, divergent region in RING-H2 domains modulate interaction specificity. ANAC contains a degenerate bipartite nuclear localization signal (NLS), while RHG1a, also identified as an ANAC interaction partner, contains a basic NLS. Both signals localized beta-glucuronidase reporter fusions to the nucleus. N-terminally truncated RHA2a also directed nuclear localization, apparently dependent on basic amino acids in the RING-H2 domain. Nuclear co-localization of the RING-H2 proteins and ANAC may enable their interaction in vivo to regulate the activity of the ANAC transcription factor.
 ...
PMID:Interactions between plant RING-H2 and plant-specific NAC (NAM/ATAF1/2/CUC2) proteins: RING-H2 molecular specificity and cellular localization. 1264 39

The MYC-like sequence CATGTG plays an important role in the dehydration-inducible expression of the Arabidopsis thaliana EARLY RESPONSIVE TO DEHYDRATION STRESS 1 (ERD1) gene, which encodes a ClpA (ATP binding subunit of the caseinolytic ATP-dependent protease) homologous protein. Using the yeast one-hybrid system, we isolated three cDNA clones encoding proteins that bind to the 63-bp promoter region of erd1, which contains the CATGTG motif. These three cDNA clones encode proteins named ANAC019, ANAC055, and ANAC072, which belong to the NAC transcription factor family. The NAC proteins bound specifically to the CATGTG motif both in vitro and in vivo and activated the transcription of a beta-glucuronidase (GUS) reporter gene driven by the 63-bp region containing the CATGTG motif in Arabidopsis T87 protoplasts. The expression of ANAC019, ANAC055, and ANAC072 was induced by drought, high salinity, and abscisic acid. A histochemical assay using P(NAC)-GUS fusion constructs showed that expression of the GUS reporter gene was localized mainly to the leaves of transgenic Arabidopsis plants. Using the yeast one-hybrid system, we determined the complete NAC recognition sequence, containing CATGT and harboring CACG as the core DNA binding site. Microarray analysis of transgenic plants overexpressing either ANAC019, ANAC055, or ANAC072 revealed that several stress-inducible genes were upregulated in the transgenic plants, and the plants showed significantly increased drought tolerance. However, erd1 was not upregulated in the transgenic plants. Other interacting factors may be necessary for the induction of erd1 in Arabidopsis under stress conditions.
 ...
PMID:Isolation and functional analysis of Arabidopsis stress-inducible NAC transcription factors that bind to a drought-responsive cis-element in the early responsive to dehydration stress 1 promoter. 1531 76

The p70 ribosomal S6 kinase (p70(s6k)) signaling pathway plays a key role in regulating the cell cycle via translational regulation of specific 5'TOP mRNAs. However, the function of this signaling pathway is still poorly understood in plants. Ectopic expression of the lily putative p70(s6k) gene, LS6K1, resulted in up-regulation of NAP (NAC-LIKE, ACTIVATED BY AP3/PI) and PISTILLATA (PI) expression, and significantly inhibited cell expansion for petals and stamens, resulting in the male sterility phenotype in transgenic Arabidopsis. Sequence analysis revealed that the genes involved in petal and stamen development, such as APETALA3 (AP3), PI and SUPERMAN (SUP), probably encode 5'TOP mRNAs. Green fluorescent protein (GFP), fused to oligopyrimidine tract sequences that were identified in the 5'-untranslated region (UTR) of AP3, PI and SUP, was translationally regulated in human cells in response to mitogen stimulation and inhibition by the macrolide antibiotic rapamycin. Furthermore, 35S::LS6K1 significantly up-regulated beta-glucuronidase (GUS) activity in the flower buds of transgenic plants carrying the GUS transgene fused to the AP3 promoter and the 5' UTR. These results have identified a novel role for the p70(s6k) gene in regulating cell division and the expansion of petals and stamens by translational regulation of the 5'TOP mRNAs once ectopically expressed in Arabidopsis.
 ...
PMID:Overexpression of the lily p70(s6k) gene in Arabidopsis affects elongation of flower organs and indicates TOR-dependent regulation of AP3, PI and SUP translation. 1965 1

The urine from mice exposed to styrene vapors (600 and 1200 mg/m(3), 6 h) was analyzed for ring-oxidized metabolites of styrene. To facilitate the identification of metabolites in urine, the following potential metabolites were prepared: 2-, 3-, and 4-vinylphenol (2-, 3-, and 4-VP), 4-vinylpyrocatechol, and 2-, 3-, and 4-vinylphenylmercapturic acid (2-, 3-, and 4-VPMA). For the analysis of vinylphenols beta-glucuronidase-treated urine was extracted and derivatized with acetanhydride/triethylamine before injection into GC/MS. Three isomers, 2-, 3-, and 4-VP, were found in the exposed urine using authentic standards. Additionally, three novel minor urinary metabolites, arylmercapturic acids 2-, 3-, and 4-VPMA, were identified by LC-ESI-MS(2) by comparison with authentic standards. Excretion of the most abundant isomer, 4-VPMA, amounted to 535 +/- 47 nmol/kg and 984 +/- 78 nmol/kg, representing approximately 0.047 and 0.043% of the absorbed dose for the exposure levels of 600 and 1200 mg/m(3), respectively. The ratio of 2-VPMA, 3-VPMA, and 4-VPMA was approximately 2:1:6. In model reactions of styrene 3,4-oxide (3,4-STO) with N-acetylcysteine in aqueous solutions and of its methyl ester in methanol, 4-vinylphenol was always the main product, while 3-vinylphenol has never been detected. No mercapturic acid was found in the reaction of 3,4-STO with N-acetylcysteine in aqueous solution at pH 7.4 or 9.7, but a small amount of 4-VPMA methyl ester was detected by LC-ESI-MS after the reaction of 3,4-STO with N-acetylcysteine methyl ester. In contrast, no mercapturic acid was found in the reaction of 3,4-STO with N-acetylcysteine in aqueous solution at pH 7.4 or 9.7. These findings indicate a capability of 3,4-STO to react with cellular thiol groups despite its rapid isomerization to vinylphenol in an aqueous environment. Moreover, the in vivo formation of 2- and 3-isomers of both VP and VPMA, neither of which was formed from 3,4-STO in vitro, strongly suggests that another arene oxide, styrene 2,3-oxide, might be a minor metabolic intermediate of styrene.
 ...
PMID:New urinary metabolites formed from ring-oxidized metabolic intermediates of styrene. 2002 Jul 50