• International Journal of Industrial Entomology and Biomaterials
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• v.9 no.2
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• pp.225-228
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• 2004

Superoxide dismutase (SOD) is an important enzyme which catalyzes superoxide radicals to hydrogen peroxide. A Cu, Zn sod-like gene was found in Bombyx mori nuclear polyhedrosis virus encoding 151 amino acids. To demonstrate its function, a recombinant virus named dsBmNPV with deleted sod gene was constructed. It was discovered that the sod gene was not essential for viral replication. Studies on growth of budded virus in BmN cells and superoxide dismutase and catalase activities in vivo after dsBmNPV infection showed that the titer of dsBmNPV decreased obviously comparing to wild type BmNPV, the sod gene was effective on genomic DNA replication of baculovirus, the peak of SOD activity of silkworm infected with wt-BmNPV appeared between 36 and 48 hrs post infection, and with dsBmNPV, it did not appear. And the changes of CAT activity after infection were similar to SOD activity.

• IMMUNE NETWORK
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• v.1 no.2
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• pp.151-161
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• 2001

Background: Inactivation in p53 tumor suppressor gene through a point mutation and deletion is one of the most frequent genetic changes found in human cancer, with 50% of an incidence. This high rate of mutation mostly suggests that the gene plays a central role in the development of cancer and the mutations detected so far were found in exons 5 to 8. Mutation of p53 locus produced accumulation of abnormal p53 protein, and negative regulation of cell proliferation and transcriptional activation as a suppressor of transformation were lost. In addition, inhibition of its normal cellular function of wild-type by mutant is an important step in tumorigenesis. Method: 4 colon cancer cell lines (SNU C1, C2A, C4, C5) were examined for mutation in exons 5 to 8 of the p53 tumor suppressor gene by PCR-SSCP analysis and expression pattern by western blotting and immunoprecipitation. p53-mediated transactivation ability were examined by CAT assay and base substitution of p53 in SNU C2A cell were detected by DNA sequencing. Results: 1) SNU C2A cell and SNU C5 cell were detected mobility shifts each in exon 5 and exon 7 of p53 gene by the PCR-SSCP method, implicating being of p53 mutation. 2) 3 colon cancer cell lines (SNU C1, SNU C2A, SNU C5) expressed wild type and mutant type p53 protein. 3) In northern blot experiment, SNU C2A and SNU C5 cell expressed high level of p53 mRNA. 4) Results of p53-mediated transactivation in colon cancer cell lines by CAT assay represented only SNU C2A cell has transcriptional activity. 5) DNA sequencing in SNU C2A cell showed missense mutation in codon 179 of one allele, histidine to arginine and wild type p53 in the other allele. Conclusion: Colon cancer cell lines showed correlation with mutation in p53 gene and accumulation of abnormal p53 protein. Colon cancer cell SNU C2A retained p53-mediated transactivation as heterozygous p53 with one mutant allele in 179 codon and the other wild-type allele.

• Journal of Korean Society of Forest Science
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• v.84 no.1
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• pp.77-86
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• 1995

To effectively modify tree function with genetic engineering, transgenes must be expressed at the proper level in the appropriate tissues at suitable developmental stages. Toward understanding the spatial and temporal expression of transgenes in woody plants, transgene expression was evaluated in three greenhouse-grown, transgenic lines of Populus alba ${\times}$ P. grandidentata hybrid clone 'Hansen'. All transgenic poplar lines possess constructs containing the bacterial nopaline synthase(nos) promoter linked to a neomycin phosphotransferase II(NPT II) selectable marker gene. In addition, each transgenic poplar line contains one of the following gene constructs : 1) a wound-inducible potato proteinase inhibitor II (pin2) promoter linked to a chloramphenicol acetyltransferase(CAT) reporter gene. 2) a nos promoter linked to a PIN2 structural gene : or 3) a Cauliflower Mosaic Virus 35s promoter linked to a PIN2 structural gene. Polymerase chain reaction(PCR) was used to verify the presence of foreign genes in the poplar genome. Enzyme-linked immunosorbent assays(ELISAs) were used to evaluate organ specific expression of the nos-NPT II construct. NPT II expression was detected in leaves, petioles, stems, and roots of transgenic poplar, thereby indicating that the nos promoter is potentially effective for general constitutive expression of transgenes. NPT expression varied among transgenic poplar lines and among organs for one transgenic line, Tr15. With Tr15, NPT II levels were highest in older leaves and petioles. These results indicate that screening of several transgenic lines may be required to identify lines with optimal transgene expression.

• The Korean Journal of Food And Nutrition
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• v.25 no.4
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• pp.863-870
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• 2012

Though hydrogen peroxide ($H_2O_2$) causes a deleterious effect to cells with its reactive oxygen species resulting in cell death, S-allyl cysteine (SAC, a bioactive organosulfur compound of aged garlic extract) has been known to have a cytoprotective effect. Few reported profiles of gene expression of $H_2O_2$ and SAC treated human cord blood derived mesenchymal stem cells (MSC). This study revealed changes in the profile of twenty-one genes grouped by oxidative stress, antioxidant, cell death, anti-apoptosis and anti-aging by quantitative real time PCR. A concentration of $100{\mu}M$ of SAC or $50{\mu}M$ of $H_2O_2$ was applied to MSC which show moderate growth and apoptosis pattern. $H_2O_2$ treatment enhanced expression of eleven genes out of twenty-one genes compared with that of control group, on the contrary SAC suppressed expression of eighteen genes out of twenty-one genes except C ros oncogene. SAC decreased expression of oxidative stress genes such as SOD1, CAT and GPX. These results seemed consistent with reports which elucidated over-expression of NF-${\kappa}$B by $H_2O_2$, and suppression of it by SAC. This study will confer basic information for further experiments regarding the effects of SAC on gene levels.

• Archives of Pharmacal Research
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• v.16 no.2
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• pp.155-157
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• 1993

DNA transfection conditions were investigated by calcium phosphate-DNA co-precipitation in SK-N-BE(2)C human neuroblastoma cells. The DNA plasmid of TH2400CAT was used in which rat tyrosine hydroxylase gene was inserted into chloramphenicol acetyltransferase reporter gent. The transfection efficiency was 25-30% and the method was simple and reproducible. So, the method will be a good tool for transient transfection analysis.

• YAKHAK HOEJI
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• v.50 no.1
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• pp.58-63
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• 2006

The antioxidant enzyme (AOE) system plays an important role in the defense against oxidative stress damage. To determine whether myricetin or myricetin/taurine can exert antioxidative effects not only by modulating the AOE system directly but also by scavenging free radical, we investigated the influence of the myricetin and taurine on cell viability ROS level, activities of different antioxidant enzyme, and the expression of different antioxidant enzyme. As results, the cell viability showed inhibition of the proliferation with treatment of 'myricetin' or 'myricetin with taruine', respectively, with dose-dependent manner. Compared to control, the treatment of 'myricetin' decreased activities and gene expressions of superoxide dismutase (SOD), and glutathione peroxidase (GPx). However, combined treatment of 'myricetin with taurine' increased activities and gene expressions of the SOD, GPx, and catalase (CAT). In addition, the combined treatment of 'myricetin with taurine' somewhat decreased ROS levels, compared to the treatment of 'myricetin'. In conclusion, our study provides that the combined treatment of different antioxidants can enhance antioxidant effects.

• Journal of Aquaculture
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• v.12 no.1
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• pp.71-77
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• 1999

The potential utility of injection media (sucrose, PEG, and liposome) was demonstrated for direct gene transfer into olive flounder (Paralichthys olivaceus) muscles. Based on the use of sucrose (final cone. 20%), PEG 8,000 (final cone. 10%) or liposome (twice us of DNA injected), the present injection strategy significantly improved the level of transgene expression as well as persistent duration of expression. The increased amounts of expression in DNA injection with sucrose, PEG, and liposome were as high as from 2.1 to 4.9-folds of conventional TE-based DNA injection. The best result was obtained from injections of liposome-encapsulated DNA in which the expression was detectable at least 32 days after injection when compared to only 8-16 days from TE-based injections.

• BMB Reports
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• v.28 no.6
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• pp.494-498
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• 1995

Maize mitochondrial tRNAs for isoleucine have been isolated using a putative $tRNA^{Ile}$ gene probe which has been previously isolated and characterized. It contains the 5'-CAT anticodon which would normally recognize the AUG methionine codon. The nucleotide sequence of one of these tRNAs has been partially determined, and contains a modified nucleotide at the first position of the anticodon. This type of posttranscriptional modification event could change the specificity of amino acid acceptance of a tRNA, unlike that deduced from the corresponding gene. An aminoacylation experiment also demonstrated that these purified tRNAs have isoleucine acceptance activity but no methionine-accepting activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.4
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• pp.510-517
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• 2016

This study was conducted to investigate the antioxidant and hepatoprotective effects of eriodictyol compound against hydrogen peroxide-induced oxidative stress in HepG2 cells by measuring expression levels of antioxidant enzymes, liver function index enzyme activities, and inhibitory effects against reactive oxygen species (ROS) production. HepG2 cell viability was assessed using 3-(4,5-dimethyl thiazole-2-yl)-2,5-diphenyl tetrazolium bromide assay. In the concentration range of $10{\sim}50{\mu}g/mL$, eriodictyol displayed over 98% cell viability in HepG2 cells. The effects of increased gene expression on hydrogen peroxide-induced oxidative stress were analyzed by monitoring antioxidant enzyme (superoxide dismutase, SOD; catalase, CAT; glutathione peroxidase, GPx) gene expression levels using real-time PCR. Eriodictyol compound significantly increased gene expression levels of SOD, CAT, and GPx in a dose-dependent manner ($10{\sim}50{\mu}g/mL$). Hepatoprotective effects against hydrogen peroxide-induced oxidative stress were analyzed by monitoring glutamic oxaloacetic transaminase (GOT), lactate dehydrogenase (LDH), and gamma-glutamyl transferase (GGT) activities in HepG2 cell culture medium using a biochemistry analyzer. Eriodictyol compound significantly reduced GOT, LDH, and GGT activities in a dose-dependent manner in HepG2 cells. ROS level in HepG2 cells was analyzed by 2',7'-dichlorofluorescein fluorescence diacetate assay, and eriodictyol compound effectively reduced the intracellular ROS level in HepG2 cells. The results reveal that eriodictyol compound can be useful for development of effective antioxidant and hepatoprotective agents.

• Korean Journal of Microbiology
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• v.21 no.2
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• pp.61-70
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• 1983

Synchronized cat kidney cells chronically infected with feline leukemia virus (FeLV) were used to study virus production, the synthesis of group specific antigen (gag) and envelope (env) proteins, the expression of env protein on the cell surface during the cell cycle, and the stability of viral RNA. As detecting method, we developed the radioimmunoassay (RIA) system using beta-emission of $^{131}I$ and demonstrated the validity of this system by comparison with routine RIA system using gamma-emission of $^{125}I$. The produced virus was analysed by developed RIA interval was determined by measuring reverse transcriptase activity. The results show that infected cells produce the complete virus particle containing products of gag, env and pol genes of FeLV, and maximum virus production occurs during mitosis of synchronized cells. Labeling of the cell surface of synchronized cells with $^{131}I$ shows that the amount of $gp70^{env}$ on the cell surface parallels cellular gorwth. Therefore, the cell cycle-dependent release of virus is not petition RIA of synchronized cells with $^{131}I$ labeled viral proteins synthesis during the cell cycle. The rate of synthesis of gag protein shows three peaks, corresponding to the $G_1,\;late\;S\;and\;late\;G_2$ phases of cell cycle. But the rate of synthesis of env protein dose not change, suggesting that in these cells the synthesis of these two gene products in controlled seperately. In Actionomycin D treated cells, the synthesis of viral proteins decreased sharply from 8 hours after treatment, and the late S and $G_2$ peaks of gag protein synthesis were disappeared. This shows the stability of viral RNA for about 6 hours in the absence of continuing viral RNA synthesis.