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 (0.02 seconds)

Mouse ornithine decarboxylase (ODCase) cDNA was expressed at a high level in an Escherichia coli mutant deficient in polyamine biosynthesis. The expression of mouse ornithine decarboxylase relieved the dependence of the mutant on an exogenous source of polyamines, presumably by providing putrescine, the product of the enzyme. The effect on the enzymatic activity of deletions that removed carboxy-terminal amino acids of the protein was determined.
Mol Cell Biol 1987 Jan
PMID:Complementation of a polyamine-deficient Escherichia coli mutant by expression of mouse ornithine decarboxylase. 355 Apr 25

In androgenized-hypophysectomized rats, ovine prolactin stimulated the activity of the ornithine decarboxylase (ODC) of the lateral lobes, but not the ventral and dorsal lobes of the prostate glands in a time- and dose-dependent fashion. High degrees of enzyme stimulation were associated with significant elevations in the endogenous levels of its product, putrescine. The relative response to prolactin over basal activities was relatively unaffected by indomethacin but decreased with cycloheximide, suggesting that prostaglandins do not mediate the effects of the hormone, but that a high rate of protein synthesis is a prerequisite for its expression. Indomethacin alone significantly increased the basal activity of the enzyme above control levels, suggesting that prostaglandins may normally exert a degree of inhibition on the ODC. The selective activation of the lateral lobe ODC supports previous reports of a differential response of the various prostatic lobes to prolactin, and also provides a convenient biochemical response for examining details of prolactin action on this organ.
Mol Cell Endocrinol 1987 Mar
PMID:Prolactin selectively stimulates ornithine decarboxylase in the lateral lobe of the rat prostate. 358 28

Cloned ornithine decarboxylase (ODC) (EC 4.1.1.17) cDNA was used to investigate the mechanisms which mediate the mitogenic induction of mammalian ODC. Stimulation of quiescent BALB/c 3T3 mouse fibroblasts with purified fibroblast and platelet-derived growth factors and with the tumor promoter 12-O-tetradecanoylphorbol-13-acetate results in a rapid and dramatic increase in ODC mRNA, similar to the increase caused by serum stimulation. Using nuclear runoff transcriptional analysis, we demonstrate that an increase in ODC transcription accounts for the mitogenic induction of ODC mRNA, and using cycloheximide together with the stimulating mitogen, we found that the mitogenic induction of ODC is dependent on ongoing protein synthesis in the stimulated cells.
Mol Cell Biol 1987 Jul
PMID:Transcriptional activation of mammalian ornithine decarboxylase during stimulated growth. 361 3

The human and animal filarial parasites Onchocerca volvulus, Dirofilaria immitis, Brugia patei and Litomosoides carinii contained low levels of putrescine but much higher levels of spermidine and spermine as estimated by ion-pair high pressure liquid chromatography; N-acetylated polyamines were present only in minute amounts. Enzyme activities of ornithine decarboxylase (EC 4.1.1.17) and arginine decarboxylase (EC 4.1.1.19), respectively, were not detectable. Experiments carried out with O. volvulus and D. immitis demonstrated the uptake and bioconversion of labeled polyamines. There is evidence for the existence of a complete reverse pathway generating putrescine from spermidine and spermine, respectively, in both worms. N-Acetylating enzyme activities were detected in 100,000 X g preparations of homogenates from D. immitis which were capable to acetylate putrescine, spermidine and spermine. Long term incubation of the worms in the presence of labeled polyamines resulted in the excretion of putrescine and N-acetylputrescine.
Mol Biochem Parasitol 1987 Jun
PMID:Polyamine metabolism in filarial worms. 362 68

A single dose of synthetic salmon calcitonin administered to rats (20 MRC U/kg body weight) stimulated the activity of ornithine decarboxylase in the brain, liver, kidney, testis and ovaries by 3-, 15-, 5-, 2- and 2-fold respectively after 4 h of the treatment. The increase in the enzyme activity in the brain, testis and ovaries was accompanied by a comparable increase in the enzyme protein content. Hepatic and renal ornithine decarboxylase concentration increased only by 2-fold. These results suggest that calcitonin influences polyamine biosynthesis through a tissue-specific regulation of the activity and/or the number of ornithine decarboxylase molecules.
Mol Cell Endocrinol 1987 Aug
PMID:Calcitonin induces ornithine decarboxylase in various rat tissues. 365 6

Ornithine decarboxylase (ODCase), the rate-limiting enzyme in polyamine biosynthesis, exhibits dramatic fluctuations in activity in response to a variety of hormones and growth factors and has been shown to be down-regulated during myogenesis. In the present study, the molecular mechanisms involved in expression of ODCase mRNA were examined in cells of the BC3H1 muscle line. Proliferating, undifferentiated cells in medium with 20% fetal calf serum displayed high levels of ODCase mRNA and enzyme activity. The transfer of proliferating cells to medium containing 0.5% serum resulted in their withdrawal from the cell cycle and a 20- to 50-fold reduction in the steady-state level of ODCase mRNA within 24 h. Down-regulation of ODCase mRNA was paralleled by a decrease in ODCase enzyme activity and ODCase gene transcription. ODCase mRNA was rapidly reinduced by exposure of quiescent, differentiated cells to medium with 20% serum or by inhibition of protein synthesis with cycloheximide. The accumulation of ODCase mRNA after mitogenic stimulation or protein synthesis inhibition was accompanied by an increase in ODCase gene transcription. The mechanisms whereby mitogens and protein synthesis inhibitors induced ODCase transcription appeared to be different since cycloheximide potentiated the effects of mitogens, resulting in superinduction of ODCase transcription to a level significantly greater than in the presence of mitogens alone. These results indicate that ODCase down-regulation during myogenesis is controlled primarily at the level of ODCase gene transcription. These data also demonstrate that ODCase expression is regulated by antagonistic signals, positive signals for transcription elicited by mitogens and negative signals from endogenous protein repressors that influence ODCase transcription.
Mol Cell Biol 1986 Aug
PMID:Mitogens and protein synthesis inhibitors induce ornithine decarboxylase gene transcription through separate mechanisms in the BC3H1 muscle cell line. 378 14

Diploid cells of Saccharomyces cerevisiae homozygous for the spe1A mutation, which eliminates ornithine decarboxylase activity, were found to sporulate at a greatly reduced frequency in the absence of polyamines. Plasmids which complement the spe1A mutation were isolated by their ability to restore sporulation competence to these cells. Three distinct plasmids were isolated. Each plasmid insert overlapped the same 8.0-kilobase region, and each plasmid restored ornithine decarboxylase activity to spe1A mutants. These plasmids also conferred ornithine decarboxylase activity to Escherichia coli EWH319 from which the ornithine decarboxylase gene is deleted. The plasmid-encoded activity expressed in E. coli resembled S. cerevisiae ornithine decarboxylase in its kinetic characteristics, indicating that the yeast ornithine decarboxylase gene was cloned. Southern blot analysis suggested that ornithine decarboxylase is a single-copy gene in S. cerevisiae. A single 2.1-kilobase transcript was demonstrated by Northern blot analysis.
Mol Cell Biol 1985 Jan
PMID:Expression of the gene for ornithine decarboxylase of Saccharomyces cerevisiae in Escherichia coli. 388 7

In the isolated perfused rat hearts, the activity of tissue ornithine decarboxylase gradually decreases over 90 min. In contrast, the activity of S-adenosylmethionine decarboxylase, lactate dehydrogenase, and glutamate-oxalacetate transaminase stays unchanged after a small decrease during the first 10 min. Ornithine decarboxylase is released from the perfused heart under conditions in which neither the lower molecular weight S-adenosylmethionine decarboxylase nor polyamines leak out. Ten minutes of ischaemia did not change the rate of release of ornithine decarboxylase. Ischaemia followed by reperfusion (20 min) increased release of ornithine decarboxylase.
J Mol Cell Cardiol 1986 Mar
PMID:Ornithine decarboxylase in perfused rat heart. 395 94

Previous investigations demonstrated that methoxychlor [1,1,1-trichloro-2,2-bis(4-methoxyphenyl)ethane] contains estrogenic contaminants and that methoxychlor per se is not an estrogen but is a proestrogen being metabolized in vivo into estrogenic products. The present study examined structurally identified methoxychlor contaminants as to their estrogenic or proestrogenic properties. Also, the estrogenic activity of demethylated metabolites of methoxychlor and of one contaminant was determined. To examine these properties, we utilized an assay developed by us that monitors whether a given compound, incubated with isolated rat uteri, can diminish the uterine cytosolic estrogen receptor and elevate the nuclear estrogen receptor and whether metabolic intervention by hepatic microsomal monooxygenase(s) is required by the respective compound for this cellular redistribution of the receptor. Of the 15 compounds examined which constitute with methoxychlor 99.5% of total technical grade methoxychlor, two compounds, 1,1-dichloro-2-(4-hydroxyphenyl)-2-(4-methoxyphenyl)ethene (mono-OH-MDDE) and 1,1,1-trichloro-2-(4-hydroxyphenyl)-2-(4-methoxyphenyl)ethane (mono-OH-methoxychlor), were active per se and two compounds, 1,1-dichloro-2,2-bis(4-methoxyphenyl)ethene (MDDE) and methoxychlor, required metabolic transformation for estrogenic activity to be manifested. Subsequently, it was shown that the mono- and bis-OH metabolites of MDDE and of methoxychlor were active estrogens and that the order of activity, either by the above procedure or in terms of relative binding affinity to rat uterine cytosolic receptor, was as follows: bis-OH-MDDE much greater than bis-OH-methoxychlor greater than mono-OH-MDDE greater than mono-OH-methoxychlor. Following the in vitro observations, the activity of MDDE and bis-OH-MDDE was determined in vivo in immature rats. It appears that both compounds are estrogenic, yielding marked elevation in ornithine decarboxylase (EC 4.1.1.17) levels and moderate increase in uterine weight. A comparison with methoxychlor and bis-OH-methoxychlor [1,1,1-trichloro-2,2-bis(p-hydroxyphenyl)ethane] demonstrates that the order of potencies is similar to that observed in the in vitro determinations. These studies demonstrate the usefulness of the in vitro assay for determining the estrogenic and proestrogenic properties of compounds of which limited quantities are available, often insufficient for in vivo determination. Also, whereas the in vitro assay is simple and rapid, a lengthy investigation might be required to determine in vivo whether a given compound is an estrogen or a proestrogen.(ABSTRACT TRUNCATED AT 400 WORDS)
Mol Pharmacol 1985 Jan
PMID:Role of hepatic monooxygenases in generating estrogenic metabolites from methoxychlor and from its identified contaminants. 396 23

Ethanol and tryptophan have been demonstrated earlier to induce a rapid stimulation of hepatic ornithine decarboxylase (ODC) activity in overnight-fasted rats. In this study the effect of the administration of retinyl acetate prior to administering ethanol or tryptophan was investigated. The levels of ODC activity in the livers of control and experimental rats were assayed in vitro by measuring the release of 14CO2 from DL-[1-14C]ornithine. Intraperitoneal administration of retinyl acetate (1 microgram/100 g body wt) 1 hr before tube feeding ethanol (0.75 g as a 50% solution/100 g body wt) or L-tryptophan (30 mg in 3 ml water/100 g body wt) and 3 hr before killing caused an enhanced stimulation of hepatic ODC activity compared to that when each agent was administered alone. In vitro [14C]leucine incorporation into protein using hepatic microsomes of tryptophan-treated rats with or without retinyl acetate was increased in comparison with that of controls while decreases were observed when using microsomes of ethanol-treated rats with or without retinyl acetate. Although retinyl acetate has been reported earlier to inhibit the stimulation of hepatic ODC activity due to a variety of agents, including some agents known as carcinogens or promoters, it did not act in this manner against the acute administration of ethanol or tryptophan.
Exp Mol Pathol 1985 Aug
PMID:Hepatic ornithine decarboxylase activity in the rat as influenced by retinyl acetate and ethanol or tryptophan. 400 39


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