Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Several novel hybridization techniques are described. Cells or specimens are treated to release nucleic acids and a liquid phase hybridization is carried out with a dA-tailed capture probe and a reporter probe in chaotropic salts or in salts containing SDS/proteinase K. In another format the tailed capture probe is preimmobilized on polystyrene and used to capture target nucleic acids from the solution. No phenol extraction or centrifugation is required to prepare the nucleic acids. Capture of the target on the poly (dT)-solid supports is used to remove excess labelled probe and sample impurities prior to non-radioisotopic or radioisotopic detection. This paper shows the advantage of a single round of capture on polystyrene, including the ability to assay large numbers of samples manually, the ability to analyse each sample for many analytes simultaneously, the use of rapid non-radioisotopic detection, and the ability to readily adapt the assay for automation.
Mol Cell Probes 1989 Jun
PMID:Nucleic acid hybridization assays employing dA-tailed capture probes. Single capture methods. 267 81

The immunological characterization of the different forms of phenol sulfotransferase (PST) in a variety of human and nonhuman tissues is described. Immunoblotting techniques revealed that polyclonal antibodies raised to human platelet MII-PST reacted with polypeptides of 32 and 34 kDa from human platelet 100,000 x g supernatant solution. Immunoblot analysis of platelet 100,000 x g supernatant solution that was fractionated over a DEAE-cellulose column indicated a close correspondence of P-PST activity, as measured by phenol sulfation, and M-PST activity, as assessed by dopamine sulfation, with the 32 and 34 kDa polypeptides, respectively. Examination of various human tissues revealed the presence of immunologically detectable levels of P-PST in liver and adrenal gland whereas both M- and P-PST were detected in placenta at a 1/10,000 dilution of the antisera. Under these conditions, PST was undetectable in human frontal cortex, pituitary gland, kidney, lung, and jejunum. Further evaluation of human liver samples from four individuals indicated a strong correlation (r = 0.94) between the amount of 32-kDa immunoreactive protein and P-PST activity. Analysis of liver samples from several animal species (monkey, rat, mouse, guinea pig, and frog) revealed the presence of immunoreactive proteins of various molecular masses, suggesting that considerable homology may exist between human and nonhuman forms of PST.
Mol Pharmacol 1989 Jul
PMID:Immunological characterization of human phenol sulfotransferase. 274 28

Glutathione (GSH) transferase isoenzymes have been partially resolved from the cytosol of Schistocephalus solidus (plerocercoid) by GSH affinity chromatography and chromatofocusing at pH 7-5. The presence of isomeric forms was also suggested by analytical isoelectric focusing and high-performance liquid chromatography (HPLC). Gel filtration and sodium dodecyl sulphate-polyacrylamide gel electrophoresis indicated that GSH transferase forms were dimers with a subunit size of approximately 24 kDa. The major GSH transferase form in S. solidus (plerocercoid) showed greater biochemical relationship to the Mu family of mammalian GSH transferase compared to the mammalian Alpha or Pi families. The major subunit purified by GSH affinity chromatography and reversed-phase HPLC also showed high N-terminal homology with the Mu family. A minor GSH transferase form appeared more biochemically related to the Alpha family with respect to substrate specificity and inhibitor sensitivity. The major GSH transferase was inhibited by haematin-related compounds, bile acids and a number of anthelmintics including members of the benzimidazole and phenol-based class of compounds. The major GSH transferase had conjugating activity with members of the trans, trans-2,4-alkadienal and trans-2-alkenal series, secondary products of lipid peroxidation.
Mol Biochem Parasitol 1989 Sep
PMID:Purification of cytosolic glutathione transferases from Schistocephalus solidus (plerocercoid): interaction with anthelmintics and products of lipid peroxidation. 277 Jul 89

Since sex steroid hormones and growth factors are known to modulate the proliferation of breast tumors, we have studied the effects of estrogen and progestin, their antagonists, and growth factors on the regulation of estrogen receptor (ER) mRNA and protein levels in T47D breast cancer cells, which contain low levels of ER, and in two sublines of MCF-7 cells which contain high ER levels. The mRNA levels were measured by Northern blot analysis using lambda OR8, a cDNA probe for ER, and protein levels were measured by hormone binding or Western blot analysis. Treatment of T47D cells with estradiol (E2) caused a 2.5-fold increase in ER mRNA (6.6 kilobases) levels after 48 h. The progestin R5020 evoked a marked decrease in ER mRNA and protein levels to 20% of control values, while the antiprogestin RU38,486 caused no change in ER. In MCF-7 cells, the effect of E2 on ER levels was dependent on the prior growth history of the cells. In cells grown in low estrogen [5% charcoal-dextran-treated calf serum with phenol red for 8 yr (MCF-7-K2)], which are still E2 responsive, treatment with E2, the antiestrogen LY117018, or both produced little change in ER mRNA or protein; in contrast, ER mRNA and protein were reduced by E2 to 40% and 50% of control levels, respectively, in MCF-7 cells (denoted MCF-7-K1) which had been maintained routinely in medium containing 5% calf serum. This decrease in ER mRNA was dose dependent; 10(-11) E2 reduced levels to 60%, and 10(-10) M E2 evoked the maximal drop to 40% of the control level in 2 days. LY117018 alone did not alter ER mRNA levels in these cells, but it completely prevented the down-regulation of ER by E2. Administration of progestin, but not antiprogestin, along with E2 partially prevented the decrease in ER evoked by E2. Addition of epidermal growth factor or insulin-like growth factor-I to MCF-7-K1 cells, which increased cell proliferation, had no detectable effect on ER levels. Treatment with transforming growth factor-beta, which decreased cell proliferation, reduced ER by about 20%.(ABSTRACT TRUNCATED AT 400 WORDS)
Mol Endocrinol 1989 Feb
PMID:Regulation of estrogen receptor messenger ribonucleic acid and protein levels in human breast cancer cell lines by sex steroid hormones, their antagonists, and growth factors. 278 42

The National Toxicology Program has undertaken a study to assess the ability of four genetic toxicology assays to predict the carcinogenicity of chemicals in 2-year rodent studies [Tennant et al.: Science 236:933-941, 1987]. Two of the assays, used for evaluating in vitro cytogenetic damage, were the SCE and chromosome aberration assays in Chinese hamster ovary cells. The results and data for 15 of the chemicals tested in these two assays are presented here. Each chemical was tested with and without exogenous metabolic activation. The chemicals tested were bisphenol A, 2-chloroethanol, C.I. acid orange 10, C.I. disperse yellow 3, C.I. solvent yellow 14, cytembena, D&C red 9, 1,2-dibromoethane, FD&C yellow 6, malaoxon, D,L-menthol, phenol, sulfisoxazole, titanium dioxide, and tris(2-ethylhexyl)phosphate. In vitro cytogenetic results from the other chemicals presented by Tennant et al. (Science 236:933-941, 1987) have been published by Galloway et al. (Environmental and Molecular Mutagenesis 10(Suppl 10): 1-175, 1987), Gulati et al. (Environmental and Molecular Mutagenesis 13:133-193, 1989), and Love-day et al. (Environmental Mutagenesis 13:60-94).
Environ Mol Mutagen 1989
PMID:Chromosomal aberrations and sister chromatid exchange tests in Chinese hamster ovary cells in vitro. IV. Results with 15 chemicals. 279 92

The simple technique for isolation of high-molecular eucaryotic DNA has been proposed. It includes cell or nuclei lysates by sodium dodecylsulfate in the presence of pronase, proteins precipitation by potassium acetate, DNA precipitation by ethanol. The DNA isolated by this technique is easily cleaved by restriction endonucleases and can be used for analysis of the unique genes by blot-hybridization. The yield of DNA is similar or somewhat higher than that in case of using the standard methods including phenol extraction or phenol-chloroform extraction.
Mol Gen Mikrobiol Virusol 1989 Jun
PMID:[Isolation of high molecular weight eukaryotic DNA with the use of potassium acetate]. 281 2

We have investigated the electronic and steric effects of substituents in the aromatic moiety of the substrate on the two principal stages of the reaction catalyzed by tyrosine-phenol-lyase. The substrate specificity of the enzyme is controlled during the stage of elimination of the aromatic ring. The process may be formally considered as an electrophilic substitution in the aromatic nucleus and includes tautomerization of the phenol group into cyclohexadienone and subsequent beta-elimination with regeneration of aromaticity in the leaving group. The OH-group in the rho-position of the ring is the first necessary condition for the stage to proceed. The same stage is also sensitive to the steric parameters of the substituent in the ring which ensures the second factor of control. When the requirements of substrate specificity are fulfilled (L-tyrosine, 3-F-L-tyrosine) the "key" stage of elimination of phenol moiety is not the rate-limiting one, the velocity of the reaction being determined by the preceding stage of alpha-proton abstraction.
Mol Biol (Mosk)
PMID:[Substrate specificity of tyrosine-phenol-lyase. Electron and steric control at the stage of aromatic moiety elimination]. 283 89

Hyperestrogenemia in humans increases both the concentration of serum T4-binding globulin (TBG) by 2- to 3-fold and the proportion having anodal mobility on isoelectric focusing (IEF). As TBG is synthesized in the liver, we studied the effect of estrogen on TBG synthesis, secretion, and degradation by cultured human hepatocarcinoma cells (Hep G2). beta-Estradiol in concentrations in the range found in pregnancy (10(-7) M) had no effect on the accumulation of immunoreactive TBG in medium over 4 days. The absence of fetal calf serum or phenol red did not alter these findings. The amount of [35S]TBG accumulated 6 h after addition of [35S]methionine was not influenced by exposure to estrogen or to serum obtained from pregnant women. However, 10(-5) M beta-estradiol suppressed TBG more severely than albumin synthesis (34% vs. 9%). The lack of an estrogen effect on TBG synthesis and secretion was supported by experiments showing no effect of estrogen on the disappearance of TBG added to the medium or the accumulation of cytoplasmic TBG mRNA. The same cultures responded to estrogen by a 10-fold increase in nuclear estrogen receptor binding sites and a 2-fold increase in apolipoprotein CII. As TBG in serum, the rate of heat denaturation was not altered in TBG synthesized by Hep G2 cells in the presence of estrogen. In contrast to the effect on TBG in serum, in Hep G2 cells estrogen did not produce an anodal shift on IEF, or increased its proportion not bound to Concanavalin A, nor reduced its clearance rate when injected into rats. However, even untreated Hep G2 cells synthesized TBG with a larger number of anodal IEF bands and proportion of Concanavalin A excluded material than TBG in pregnancy serum. Results support our hypothesis, based on analysis of TBG in pregnancy, that estrogen-induced serum TBG elevation may not be mediated through an increase in synthesis. The failure to observe estrogen induced changes in oligosaccharide structure does not exclude estrogen responsivity of Hep G2 cells. Such effect could be masked by the marked constitutive increase in number of oligosaccharide chain antennae typical in this and other neoplastic tissues.
Mol Endocrinol 1988 Apr
PMID:Effect of estrogen on the synthesis and secretion of thyroxine-binding globulin by a human hepatoma cell line, Hep G2. 283 62

The 4-(m-OH-phenyl)piperidines are a flexible fragment of the morphine/benzomorphan fused-ring opioids. Analogs in this family were synthesized with varying 4-alkyl substituents increasing in bulk from H through methyl, n-propyl, to t-butyl, each with the three N-substituents methyl, allyl, and phenethyl. These twelve compounds were evaluated for analgetic agonism in mice using two different models for antinociceptive activity, acetic acid writhing and tail-flick, the latter by both subcutaneous and intracerebroventricular routes of administration. Antagonism to morphine analgesia was also measured by the mouse tail-flick procedure. Binding affinities of these new analogs to different opioid receptor subtypes were determined. Energy conformational calculations on these compounds were also carried out using the empirical energy program called MOLMEC, in order to better understand how the 4-R substituents modulate receptor binding affinities and efficacies. The results obtained show that, in general, the compounds studied are mu-selective and vary in agonist potency from weak to morphine-like. Significant differences in rank order of analgetic potencies and their relationship to receptor affinities were obtained from the results of subcutaneous and intracerebroventricular administration. Results of energy-conformational calculations for twelve N-methyl compounds indicate that those with 4-alkyl substituents favor a common, non-morphine-like phenyl axial conformation. The 4-t-butyl compounds are, in fact, the first simple mono-alkyl-substituted 4-phenyl-piperidines predicted to definitely exist in a phenyl axial conformation, as confirmed by X-ray analysis. On the basis of this common phenyl axial conformation, the observed variation in mu receptor affinities and efficacies of the 4-methyl, 4-n-propyl, and 4-t-butyl compounds could be understood and the behavior of 4-ethyl and 4-isopropyl analogs predicted. Two equatorial conformers (rotamers) were found to be the preferred forms of the analogs with 4-R being H or an ester group, or with a 3-methyl group added trans (beta) to the 4-R group. Taking into account the rotational flexibility of these analogs, these two conformers could be used to understand differences in high and low efficacy compounds observed among analogs with preferred phenyl equatorial conformations. None of the analogs exhibit a fused-ring-like N-substituent modulation of efficacy. This result can, perhaps, be understood by their inability in any proposed conformer to totally mimic key receptor interactions of both the phenol-OH and N-substituent portions of the fused compounds.
Mol Pharmacol 1988 Sep
PMID:Structure-activity studies of morphine fragments. I. 4-alkyl-4-(m-hydroxy-phenyl)-piperidines. 284 51

We have developed and compared two DNA dot hybridization methodologies with similar probes (radioisotope-labelled and biotin-labelled) to detect varicella-zoster virus (VZV) DNA in three different cell cultures at varying times post-infection. Control cultures included uninfected monolayers of the same cells. Cellular DNA was isolated by a standard phenol extraction method, after which the DNA was quantified, serially diluted and blotted onto nitrocellulose or nylon membranes. The VZV DNA probe, which consisted of the large Hind III A fragment (27 of the total 125 kbp), was produced in two separate nick translation systems. The first contained 100 microCi [32P] and 0.4 microgram Hind III fragment A of the varicella genome, while the second probe employed a biotin-7-dATP analogue and 1.0 microgram of the Hind III fragment A. Direct visualization on the membrane or the exposed radiographic film showed a dot of varying intensity whenever viral genome was detected with either the biotin or the radioactive probe, respectively. With the [32P]-labelled probe, we detected VZV genomic sequences within 0.5 microgram total DNA at 12 h post-infection. This amount corresponded to approximately 5-10 pg of viral DNA. By comparison, hybridization with the biotin-labelled probe required 0.5-1.0 micrograms total DNA from infected cells. Similar tests on DNA extracted from uninfected cell samples were negative with both probes.
Mol Cell Probes 1988 Sep
PMID:Biotinylated and radioactive DNA probes for detection of varicella-zoster virus genome in infected human cells. 285 37


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