• Title/Summary/Keyword: DNA Synthesis Inhibition

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Insect Ornithine Decarboxylase (ODC) Complements SPE1 Knock-Out of Yeast Saccharomyces cerevisiae

  • Choi, Soon-Yong;Park, Hee Yun;Paek, Aron;Kim, Gil Seob;Jeong, Seong Eun
    • Molecules and Cells
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    • v.28 no.6
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    • pp.575-581
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    • 2009
  • Ornithine decarboxylase (ODC) is a rate-limiting enzyme in the biosynthesis of polyamines, which are essential for cell growth, differentiation, and proliferation. This report presents the characterization of an ODC-encoding cDNA (SlitODC) isolated from a moth species, the tobacco cutworm, Spodoptera litura (Lepidoptera); its expression in a polyamine-deficient strain of yeast, S. cerevisiae; and the recovery in polyamine levels and proliferation rate with the introduction of the insect enzyme. SlitODC encodes 448 amino acid residues, 4 amino acids longer than B. mori ODC that has 71% identity, and has a longer C-terminus, consistent with B. mori ODC, than the reported dipteran enzymes. The null mutant yeast strain in the ODC gene, SPE1, showed remarkably depleted polyamine levels; in putrescine, spermidine, and spermine, the levels were > 7, > 1, and > 4%, respectively, of the levels in the wild-type strain. This consequently caused a significant arrest in cell proliferation of > 4% of the wild-type strain in polyamine-free media. The transformed strain, with the substituted SlitODC for the deleted endogenous ODC, grew and proliferated rapidly at even a higher rate than the wild-type strain. Furthermore, its polyamine content was significantly higher than even that in the wild-type strain as well as the spe1-null mutant, particularly with a very continuously enhanced putrescine level, reflecting no inhibition mechanism operating in the putrescine synthesis step by any corresponding insect ODC antizymes to SlitODC in this yeast system.

Cloning of Elicitor-Inducible 5-epi-Aristolochene Hydroxylase in Tobacco Cell Suspension Culture (담배 현탁배양 세포의 Elicitor 유도성 5-epi-Aristolochene Hydroxylase 유전자의 클로닝)

  • Soon Tae Kwon;In-Jung Lee;Joseph Chappell
    • Journal of Life Science
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    • v.8 no.5
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    • pp.604-613
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    • 1998
  • The last enzyme of the sesquiterpen phytoalexin capsidiol synthesis in tobacco cell, 5-epi-aristolochene hydro-xylase which convert 5-epi-aristolochene (EAS) to capsidiol, was cloned by a reverse transcription polymerase chain reaction strategy and cDNA library screening. Cloned CYP-B3 contained high probability amino acid matches to known plant cytochrome P450 sequences and open reading frame with the conserved FxxGxRxCxG heme-binding region. Transcripts of CYP-B3 were not detected in control cells, but induced in elicitor-treated cells. Furthermore, CYP-B3 transcripts were induced by fungal extracts and cellulase but not by other stimuli(chilling, heat shock and 2,4-D). Induction of CYP-B3 transcripts by elicitor treatment was not affected by ancymidol and ketoconazole treat-ments suggesting that an inhibition of hydroxylase activity by Cyt P450 inhibitors resulting from post translational processing event.

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The Effect of Herbs on Inhibition of HBeAg Production in HepG2.2.15 Cell line (수종의 한약재가 HepG 2.2.15 Cell의 HBeAg발현 억제에 미치는 효과(效果))

  • Woo, Hong-Jung;Lee, Jang-Hoon;Kim, Young-Chul
    • The Journal of Internal Korean Medicine
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    • v.20 no.1
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    • pp.122-132
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    • 1999
  • Purpose : Hepatitis B virus DNA transfected cell line(HepG2.2.15) was cultured to evaluate the effect of herbs on the expression of HBeAg and the replication of HBV. HepG2.2.15 produces HBV particles as well as viral proteins into cell culture media. Methods : Extracts of herbs were adminitered to the cells on the proper concentration. Culture media was collected 48 hours after the herbal administration and HBeAg level in the media was examined by ELISA method. To confirm that the anti-viral effect was not due to direct cytotocixity of the extracts, normal cell proliferation was shown by cell counting. And as of the interference in protein synthesis of HepG2.2.15 by herb-extracts, we used the result of study that we performed before by ${\alpha}FP$ assay using EIA method. Results& Conclusion : Herb medicines like 地楡(Sanguisorbae Radix) and 覆盆子(Rubi Frusctus) showed significant inhibitory effect on HBeAg expression at p<0.01 and 五味子(Acanthopanacis Cortex) at p<0.05. Whereas, though some herbs such as ?草根(Rubiae Radix), 山査(Crataegii Fructus), 白芍藥(Paeoniae Radix Alba), and 大黃(Rhei Radix et Rhizoma) showed the tendecy to suppress HBeAg. most of them were not significant statistically. From the above, we could conclude that those herb medicines can be applied to patients effectively and further studies on effective fraction of some herbs are thought to be needed.

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Genes involved in leaf senescence and regulation of their expression

  • Watanabe, Akira;Fujiki, Yuki;Yoshikawa, Yoko;Biswall, Basanti;Ito, Masaki
    • Proceedings of the Botanical Society of Korea Conference
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    • 1999.07a
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    • pp.63-67
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    • 1999
  • We have isolated more than a dozen cDNA clones corresponding to genes that were expressed in Arabidopsis leaves when they were kept in the dark. The nucleotide sequence analysis showed that some of the clones encoded proteins with significant homology to $\beta$-glucosidase (din2), branched-chain $\alpha$-keto acid dehydrogenase subunit E1$\beta$(din3), and another subunit E2 (din4), yeast RAD23 (din5), asparagine synthetase (din6), pre-mRNA splicing factor SRp35 (din7), phosphomannose isomerase (din9), seed imbibition protein (din10), and 2-oxoacid-dependent oxidase (din11). Accumulation of transcripts from din3,4,6 and 10 occurred rapidly after the plants were transferred to darkness. Transcripts from din2,9, and 11 could be detected only after 24 h of dark treatment. Inhibition of photo-synthesis by DCMU strongly induced the accumulation of transcripts from those genes, and application of sucrose to detached leaves suppressed the accumulation both in the dark and by DCMU. These observations indicate that expression of the genes is caused by sugar starvation resulted from the cessation of photosynthesis. We further showed that din2-encoded protein also accumulated in senescing leaves. Given these results, possible roles of din genes in leaves in the dark and senescing leaves are discussed.

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Berberine Inhibits the Production of Lysophosphatidylcholine-induced Reactive Oxygen Species and the ERK1/2 Pathway in Vascular Smooth Muscle Cells

  • Cho, Bong Jun;Im, Eun Kyoung;Kwon, Jun Hye;Lee, Kyung-Hye;Shin, Hye-Jin;Oh, Jaewon;Kang, Seok-Min;Chung, Ji Hyung;Jang, Yangsoo
    • Molecules and Cells
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    • v.20 no.3
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    • pp.429-434
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    • 2005
  • Lysophosphatidylcholine (lysoPC) induces vascular smooth muscle cell (VSMC) proliferation and migration, which has been proposed to initiate the intimal thickening in coronary atherosclerotic lesions. Berberine is an alkaloid in Berberis aquifolium and many other plants. Recently, it has been shown to have beneficial effects on the cardiovascular system, such as anti-hyperglycemic and cholesterol-lowering activity. In this study, we investigated its effects on lysoPC-induced VSMC proliferation and migration. Berberine inhibited lysoPC-induced DNA synthesis and cell proliferation in VSMCs, as well as migration of the lysoPC-stimulated VSMCs. It also inhibited the activation of extracellular signal-regulated kinases (ERKs) and reduced transcription factor AP-1 activity and the lysoPC-induced increases in intracellular reactive oxygen species (ROS). These results indicate that the inhibitory effects of berberine on lysoPC-stimulated VSMC proliferation and migration are attributable to inhibition of ROS generation and hence of activation of the ERK1/2 pathway. This suggests that berberine has potential in the prevention of atherosclerosis and restenosis.

Effects of DMTU and SOD on Ultrastructural Changes of Gastric Chief Cells in Adriamycin Treated Rats (Superoxide dismutase 및 Dimethyl thiourea가 흰쥐 위샘 으뜸세포에서 Adriamycin 투여 후 나타나는 미세구조의 변화에 미치는 영향)

  • Paik, Doo-Jin;Chang, Hyung-Shim;Chung, Ho-Sam
    • Applied Microscopy
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    • v.28 no.2
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    • pp.225-236
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    • 1998
  • Adriamycin is a one of anthracyclin antibiotics isolated from the culture media of Streptomyces peucetius var casius. The formation of reactive oxygen metabolite by redox cycling during the metabolism and the inhibition of DNA synthesis results in antineoplastic effects of adriamycin. The authors have demonstrated the effects of SOD(superoxide dismutase) or DMTU (dimethyl thiourea), which are used as an antioxidant, on the ultrastructural changes of the gastric chief cells after the administration of adriamycin in the rat. Adriamycin (30 mg/kg) was administered intraperitoneally to the Sprague-Dawley rats weighing about 220 gm and SOD (15000 unit/kg) or DMTU (500 mg/kg) were administered intraperitoneally to the rats 30 minutes after the administration of adriamycin. The gastric chief cells 24, 48 and 72 hours after the administration of adriamycin were observed with Hitachi-600 electron microscope. The results were as follows. 1. SOD or DMTU alone did not affect the ultra structures of the gastric chief cells in the rat. 2. Dilation, sacculation and segmentation of the cisternae of rough endoplasmic reticulum, dilation of the saccules of Golgi complex and dilated mitochondria with electron lucent matrix were seen in the adriamycin treated rats. In the course of time, the ultrastructures of the chief cell changed markedly. 72 hours after drug administration, severely dilated cisternae of rough endoplasmic reticulum, with clumping of chromatin around the nuclear envelope and mitochondria with electron lucent matrix and dilated cristae were seen in the chief cell. 3. The treatment of SOD is more effective than DMTU to attenuated the ultrastructural changes of the chief cells in the adriamycin administered rat. Consequently it is suggested that adriamycin would induce the degenerative changes of the organelles of the chief cell. The treatment of SOD is more effective than DMTU to attenuate the adriamycin induced damage.

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Effect of Halophilic Bacterium, Haloarcula vallismortis, Extract on UV-induced Skin Change (호염 미생물(Haloarcula vallismortis) 용해물의 자외선유발 피부변화에 대한 효과)

  • Kim, Ji Hyung;Shin, Jae Young;Hwang, Seung Jin;Kim, Yun Sun;Kim, Yoo Mi;Gil, So Yeon;Jin, Mu Hyun;Lee, Sang Hwa
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.41 no.4
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    • pp.341-350
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    • 2015
  • Skin carrys out protective role against harmful outer environment assaults including ultraviolet radiation, heavy metals and oxides. Especially, ultraviolet-B (UVB) light causes inflammatory reactions in skin such as sun burn and erythma and stimulates melanin pigmentation. Furthermore, the influx of UVB into skin cells causes DNA damage in keratinocytes and dermal fibroblasts, inhibition of extracellular matrix (ECM) synthesis which leads to a decrease in elasticity of skin and wrinkle formation. It also damages dermal connective tissue and disrupts the skin barrier function. Prolonged exposure of human skin to UVB light is well known to trigger severe skin lesions such as cell death and carcinogenesis. Haloarcula vallismortis is a halophilic microorganism isolated from the Dead Sea, Its growth characteristics have not been studied in detail yet. It generally grows at salinity more than 10%, but the actual growth salinity usually ranges between 20 to 25%. Because H. vallismortis is found mainly in saltern or salt lakes, there could exist defense mechanisms against strong sunlight. One of them is generation of additional ATP using halorhodopsin which absorbs photons and produces energy by potential difference formed by opening the chloride ion channel. It often shows a color of pink or red because of their high content of carotenoid pigments and it is considered to act as a defense mechanism against intense UV irradiation. In this study, the anti-inflammatory effect of the halophilic microorganism, H. vallismortis, extract was investigated. It was found that H. vallismortis extract had protective effect on DNA damage induced by UV irradiation. These results suggest that the extract of halophilic bacterium, H. vallismortis could be used as a bio-sunscreen or natural sunscreen which ameliorate the harmful effects of UV light with its anti-inflammatory and DNA protective properties.

Study on the Genetic Characteristics of Waterlogging Tolerant Pepper (Capsicum annuum L.) for Breeding Tolerant Varieties against Flooding Stress (내습성 고추 품종 육성을 위한 선발계통의 유전적 특성 구명)

  • Yang, Eun Young;Chae, Soo-Young;Hong, Jong-Pil;Lee, Hye-Eun;Park, Eun Joon;Moon, Ji-hye;Park, Tae-Sung;Roh, Mi-Young;Kim, Ok Rye;Kim, Sang Gyu;Kim, Dae Young;Lee, Sun Yi;Cho, Myeong Cheoul
    • Journal of Life Science
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    • v.27 no.10
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    • pp.1111-1120
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    • 2017
  • This study was conducted to select pepper lines that were tolerant to excessive water injury among the pepper germplasm and investigate the genetic characteristics of those lines to contribute to the breeding of pepper cultivars with stable productivity in abnormal weather. Each of the tolerant and susceptible lines went through immersion treatment, and differentially expressed genes between them were analyzed. The tolerant line showed increased expression of the CA02g26670 gene, which is involved in the CONSTANS protein pathway and regulation of flowering by day length, but it exhibited decreased expressions of CA01g21450, CA01g22480, CA01g34470, CA02g00370 and CA02g00380. The susceptible line showed increased gene expressions of CA02g09720, CA02g21290, CA03g16520, CA07g 02110, and CA12g17910, which are involved in the inhibition of proteolytic enzyme activity, DNA binding, inhibition of cell wall-degrading enzyme, and inhibition of nodulin, respectively. Meanwhile the expressions of CA02g02820, CA03g21390, CA06g17700 and CA07g18230 decreased in the susceptible line, in relation to calcium-ion binding, high temperature, synthesis of phosphocholine and cold stress, respectively. The expressions of genes related to apoptosis and peroxidase increased, while that of CA02g16990, which functions as a nucleoside transporter, decreased in both the tolerant and susceptible lines. Based on the different gene expressions between the tolerant and susceptible lines, further studies are needed on breeding abiotic stress-tolerant lines.

Analysis of antibiotic susceptibility of Salmonella Enteritidis isolated from Gyeongnam province and the bacterial genotyping by using RAPD-PCR (경남지역에서 분리한 Salmonella Enteritidis의 항생제 감수성 검사 및 random amplification polymorphic DNA (RAPD)-PCR을 이용한 유전형 분석)

  • Kim, Eun-Gyeong;Kim, Min-Kyung;Kwon, Hyun-Ae;Youn, Do-Kyung;Koo, Jeong-Heon;Park, So-Yeon;Lee, Hui-Geun;Jo, Myeong-Hui;Hah, Do-Yun;Kim, Cheol-Ho;Hwang, Bo-Won;Kim, Sang-Hyun
    • Korean Journal of Veterinary Service
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    • v.41 no.3
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    • pp.149-155
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    • 2018
  • Salmonella Enteritidis (S. Enteritidis) are found in animals, humans, and environment. In addition, S. Enteritidis draws attention to the public health concerns due to carriage of antibiotic resistance traits. For these reasons, the prevalence and antibiotic resistance patterns of S. Enteritidis are significant issues with regard to public health. To address this issues, a total of 24 strains of S. Enteritidis from 164 samples collected from several slaughterhouses in Gyeong-Nam province in order for antibiotic resistance profiles. Subsequently, we characterized the genotyping by random amplification polymorphic DNA (RAPD)-PCR. As a result, very high level of resistance to protein synthesis inhibition antibiotics and most isolates were susceptible to others. Six random primers were used for RAPD-PCR to reveal genotypes of S. Enteritidis isolates. One of the primer, P1245, generated 147 distinct RAPD-PCR fragments ranging from 400~3000 bp. The number of RAPD-PCR products ranged from 4 to 8 for this primer. The RAPD-PCR fragments could be placed these strains into 3 subgroups and 2 classes by UPGMA cluster analysis. Interestingly, several S. Enteritidis that isolated from different slaughterhouses showed same genotype. These results showed only limited genetic variation among the isolates, those were grouped into a few different patterns of antibiotic resistance.

Immunohistochemical and Immunogold Electron Microscopic Studies on Effects of Cis-platin on the Ciliogenesis of Rat Oviducts (Cis-Platin이 흰쥐 난관의 섬모형성에 미치는 영향에 대한 면역조직학적 및 면역도금법에 의한 전자현미경적 연구)

  • Kim, Jin-Kook;Kim, Won-Kyu;Paik, Doo-Jin;Chung, Ho-Sam
    • Applied Microscopy
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    • v.30 no.1
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    • pp.45-59
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    • 2000
  • Cis-platin is a widely used anticancer drug against certain solid tumors such as malignant ovarian tumor, malignant carcinoma of head and neck, bladder cancer and cervical cancer of uterus, and its major mechanism of action is inhibition of DNA synthesis of the tumor cell. To investigate the inhibitory effects of cis-platin on the ciliogensis of the ciliated cells in the mucosa of oviduct, the author pursued the alterations of $\alpha-tubulin$, which is the main constituent of the microtubles in cilia, after cis-platin treatment. To eliminate the possible variations due to ovarian cycle, female Spargue-Dawley rats ($150\sim200gm$ in B.W.) were pretreated with estradiol benzoate (20 mg/kg, once a day, for 4 consecutive days). Animals were administrated with cis-platin (6 mg/kg, i.p.) and sacrificed at 1day, 3days, 5days and 7days after treatment, respectively. Immunohistochemistry for $\alpha-tubulin$ using mouse anti-rat $\alpha-tubulin$ monoclonal antibody as primary antibody was done. Immunogold electronmicroscopy for intracellular distributions of $\alpha-tubulin$ was also performed with same primary antibody and Goat anti- mouse IgM which is preconjugated with gold particles of 15 nm as secondary antibody. The results obtained were as follows; 1. Strong immunoreactivity of $\alpha-tubulin$ was observed in ciliated cells of oviducts at 1, 3 and 5 days after estradiol pretreatment. 2. Weak immunoreactivity of $\alpha-tubulin$ was observed in ciliated cells of oviducts at 1 and 3 days after cis-platin treatment but it was recovered to strong immunoreactivity in 5 days 3. In immunogold electronmicroscopy, density of gold particles for $\alpha-tubulin$ reactions was decreased in apical cytoplasm, but few changes were observed in basal body or cilia at 1 and 3 days after cis-platin treatment. From these above results, it is indicated that synthesis of $\alpha-tubulin$ in ciliated cells of rat oviduct is inhibited by cis-platin treatment.

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