• Journal of the Korean Society of Food Science and Nutrition
• /
• v.24 no.3
• /
• pp.415-419
• /
• 1995

Ornithine decarboxylase(ODC) catalyzes the first and key step in the polyamine biosynthetic pathway. Ornithine decarboxylase is known to the enzyme that increase substantially its activity in regenerating liver. We found that activity and mRNA level for ODC increase significantly after partial hepatectomy in the rat. After laparotomy, there was significant decrease in activity ; however, mRNA content was unaltered in contrast to previous reports of no change in ornithine decarboxylase and thymidine kinase after sham hepatectomy. This may be mediated by the decrease in food intake after hepatectomy. Therefore it is necessary to examine the effect of food intake after hepatectomy on the ODC activity and mRNA level in the future.

• Journal of Environmental Health Sciences
• /
• v.21 no.1
• /
• pp.78-85
• /
• 1995

Ornithine decarboxylase(ODC) is an indicate enzyme in carcinogenesis. We divided Sprague Dawley rats into six groups: control, electric field exposure, X-ray only irradiation, X-ray irradiation with electric field exposure group, Sr-90 injected group and Sr-90 and electric field complex exposure group. The ODC activity was measured in rat's bone marrow cell every week. The results were summarized as follows: The ODC activitied was increased in X-ray irradiated, Sr-90 injected and Sr-90 and electric field complex exposed group as compared with that of control(p<0.05). The ODC activity was increased comparing that of control neither in X-ray and electric field complex exposed group nor electric field only exposed group. This result suggests that the electric field doesn't have myeloid carcinogenicity and myeloid cancer incidence caused by ionized radiation is suppressed by electric field exposure.

• BMB Reports
• /
• v.34 no.5
• /
• pp.472-477
• /
• 2001

Ornithine decarboxylase (ODC, EC 4.1.1.17) is the first and key enzyme in eukaryotic polyamine biosynthesis. The cDNA encoding ornithine decarboxylase from Nicotiana glutinosa was cloned ($GeBank^{TM}$ AF 323910) and expressed in E. coli. Site directed mutagenesis were performed on several highly conserved cysteine residues. Among the mutants, C115A showed significant changes in the kinetic properties. The $K_m$ value of the C115A mutant was $1790\;{\mu}M$, which was 3-fold higher than that of the wild-type ODC. There was a dramatic decrease in the $k_{cat}$, values of the C115A mutant, compared to that of the wild-type ODC, which had a $k_{cat}$ value of $77.75\;s^{-1}$. C115A caused a shift in the optimal pH from 8.0 to 8.4. Considering these results, we suggest that cys-115 is involved in the catalytic activity of N. glutinosa ODC.

• 한국생물공학회:학술대회논문집
• /
• 2003.04a
• /
• pp.736-738
• /
• 2003

Ornithine decarboxylase (ODC) is the key enzyme in the synthetic pathway of polyamines. This enzyme is a homodimeric and a pyridoxal 5-phosphate (PLP) dependent enzyme. We have isolated, a cDNA clone encoding ODC from brain cDNA library constructed from flounder (Paralichthys olivaceus). The ODC cDNA contained a complete ORF consisting of 460 amino acids and one stop codon with comparison to nucleotide sequences of the flounder, zebrafish and rat ODC genes, the ODC genes were highly conserved. The transcription of ODC was analyzed with reverse transcription-polymerase chain reaction (RT-PCR) species in brain, kidney, liver, and embryo.

• Asian-Australasian Journal of Animal Sciences
• /
• v.7 no.1
• /
• pp.119-124
• /
• 1994

Experiments were performed to determine age-associated changes in ornithine decarboxylase (ODC) gene and Ha-ras cellular oncogene expression in tissues of female rats. In the kidney, ODC mRNA levels did not show age-associated changes, while ODC enzyme activities were decreased with advancing age from 3 to 10 months. These results suggest that post-transcriptional mechanism (s) are involved in the age-dependent decrease in renal ODC enzyme activity. In addition, we found no correlation between testosterone-induced renal ODC expression and DNA methylation pattern. Ha-ras mRNA levels in brain decreased as animals aged from 3 to 6 months, while renal Ha-ras mRNA levels were not influenced by age. Results demonstrate the age-dependent expression of Ha-ras in a tissue-specific manner.

• BMB Reports
• /
• v.34 no.5
• /
• pp.408-414
• /
• 2001

Ornithine decarboxylase (EC 4.1.1.17) is an essential enzyme for polyamine synthesis and growth in mammalian cells and plants. We compared the biochemical and immunological properties of rat and Nicotiana glutinosa ODC by cloning and expressing the recombinant proteins. The primary amino acid sequence between rat and N. glutinosa ODC had a 40% homology The molecular weight of the overexpressed rat ODC was 53 kDa, and that of N. glutinosa was 46.5 kDa. Adding 1 mM of putrescine to the enzyme reaction mixture inhibited both rat and N. glutinosa ODC activity to 30%. Agmatine had an inhibitory effect only on N. glutinosa ODC. Cysteine and lysine modifying reagents reduced both ODC activities, verifying the key roles of cysteine and lysine residues in the catalytic mechanism of ODC. ELISA was performed to characterize the immunological difference between the rat and plant ODC. Both the rat and N. glutinosa ODC were recognized by the polyclonal antibody that was raised against purified N. glutinosa ODC, but the rat ODC was 50-fold less sensitive to the antibody binding. These results indicate that even though both ODCs have the same evolutionary origin, there seems to be a structural distinction between the species.

• BMB Reports
• /
• v.39 no.6
• /
• pp.730-736
• /
• 2006

To evaluated the effect of recombinant adenovirus Ad-ODC-AdoMetDCas which can simultaneously express both antisense ornithine decarboxylase (ODC) and S-adenosylmethionine decarboxylase (AdoMetDC) on cell cycle distribution in colorectal cancer cell and investigated underlying regulatory responses, human colorectal cancer cells HT-29 were cultured in RPMI 1640 medium and infected with Ad-ODC-AdoMetDCas. Cell cycle progression was detected by flow cytometry analysis. The expression levels of cell cycle regulated proteins were measured by Western blot analysis. The mRNA level of cyclin D1 was measured by RT-PCR. And a luciferase reporter plasmid of cyclin D1 promoter was constructed to observe the effect of Ad-ODC-AdoMetDCas on cyclin D1 promoter activity. The results showed that recombinant adenovirus Ad-ODC-AdoMetDCas significantly induced $G_1$ arrest, decreased levels of cyclin D1 protein and mRNA and suppressed the promoter activity. Ad-ODC-AdoMetDCas also inhibited nuclear translocation of $\beta$-catenin. In conclusion, downregulation of ODC and AdoMetDC mediated by Ad-ODC-AdoMetDCas transfection induces $G_1$ arrest in HT-29 cells and the arrest was associated with suppression of cyclin D1 expression and inhibition of $\beta$-catenin nuclear translocation. As a new anticancer reagent, the recombinant adenovirus Ad-ODC-AdoMetDCas holds promising hope for the therapy of colorectal cancers.

• BMB Reports
• /
• v.34 no.5
• /
• pp.478-483
• /
• 2001

We examined the effect of CsCl and spermine on the induction of ornithine decarboxylase (ODC), a key enzyme in polyamine synthesis form Glycine max axes. Transcription of the ODC gene was induced by 0.1 and 1 mM of CsCl, and the amount of putrescine was increased 3.5-fold by 1 mM CsCl treatment. Spermine also induced the expression of the ODC gene in a die dependent manner. However, CsCl provoked an increase in the active phosphorylated ERK (pERK), a central element of the mitogen-activated protein kinase (MAPK) cascade. Our data demonstrates an interaction between the ODC induction and the MAPK signaling pathway, and suggests that the latter may be involved in cell signaling in salt-stressed plants.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.5
• /
• pp.2425-2427
• /
• 2012

Ornithine decarboxylase (ODC), the first enzyme in the polyamine biosynthesis, plays an important role in tumor progression, cell proliferation and differentiation. In recent years, ODC has been the subject of intense study among researchers, as a target for anti-cancer therapy and specific inhibitory agents, have the potential to suppress carcinogenesis and find applications in clinical therapy. In particular, it is suggested that ODC is a promising candidate target for natural products in cancer chemoprevention. Future exploration of ornithine decarboxyalse inhitors present in nature may offer great hope for finding new cancer chemporeventive agents.

• Journal of Plant Biology
• /
• v.39 no.2
• /
• pp.107-112
• /
• 1996

To study the compensatory aspect of putrescine biosynthetic enzyme n tobacco suspension cultured cells, we examined the contents of the cellular polyamines and the activities of arginine decarboxylase (ADC, EC 4.1.1.19) and ornithine decarboxylase (ODC, EC 4.1.1.17) in the tobacco suspension cells treated with $\alpha$-difluoromethyl arginine (DFMA) or $\alpha$-difluoromethyl ornithine (DFMO). In the untreated cells, the content of the cellular putrescine was decreased during the first 3 hours and then subsequently increased. However, the content of the cellular spermidine and spermine remained constant during the incubation time. While ADC activity increased after 6 hours, ODC activity decreased following the rapid increase until 6 hours. DFMA induced the decrease in the contents of putrescine and spermidine, and the increase in that of spermine. It also caused the inhibition of ADC and ODC activities throughout the incubation time. DFMO produced the stimulation of ADC activity about 2 times of untreated cells and the decrease in the content of putrescine about 50% of them at 12 hour. The application of putrescine or cycloheximide prevented the increase of ADC activity by DFMO but that of actinomycin-D did not show any detectable effect. The stimulation of ADC activity by DFMO in tobacco suspension cultured cells was probably due to the enhancement of de novo synthesis for ADC protein, which might be regulated in the translation step by the content of the cellular putrescine.