• Archives of Pharmacal Research
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• 제12권3호
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• pp.207-213
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• 1989

This study was performed to investigate the mechanism of in vitro cytotosic actions of polyacetylenes which are panaxydol, panaxynol and panaxytriol isolated from Panax ginseng C. A. Meyer. DNA synthesis of L1210 cells was significantly inhibited with dose dependent pattern when L1210 cells were treated for 1 hour with over 5 .mu.g/ml of polyacetylenes. Panaxydol which had the most potent cytotoxicity among three polyacetylenes showed also the strongest inhibitory effect on DNA synthesis. Intracellular cyclic AMP levels of L1210 cells treated with 2.5 $\mu$g/ml of panaxydol or panaxytriol were significantly elevated on the incubation duration. The elevation of cyclic AMP levels by panaxytriol was higher than that by panaxydol, but no significant increase in cyclic AMP by panaxynol was observed. All three polyacetylenes had no effect on glycolysis of L1210 cells. Electron microscopic observations revealed that polyacetylenes caused damage to plasma membranes of L1210 cells in proportion to their cytotoxicities at each $ED_{50}$ value (panaxydol > panaxynol> panaxytriol). These results suggest that cytotoxicities of polyacetylenes against L1210 cells might be mediated by elevated cyclic AMP level, even though the relationship among their cytotoxicities, inhibitory effect on DNA synthesis and ability to elevation of cyclic AMP level are not fully agreed, and might be also related to membrane damage.

• Molecules and Cells
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• 제19권2호
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• pp.228-231
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• 2005

Recent characterization of several genes involved in plant defense responses suggested that ubiquitin-mediated protein degradation has a role in these responses. We isolated two cDNAs (NtUBA1 and NtUBA2) encoding ubiquitin-activating enzyme (E1) from Nicotiana tabacum cv. BY-2. The open reading frames of both encoded 1080 amino acids, corresponding to molecular masses of 120 kDa. The E1s and corresponding transcripts were upregulated by infection with tobacco mosaic virus (TMV) and tomato mosaic virus (ToMV), and to a lesser extent by cucumber mosaic virus (CMV). Furthermore, they were also upregulated by wounding stress, and the plant hormones salicylic acid, jasmonic acid and the ethylene precursor, aminocyclopropane-1-carboxylic acid (ACC). Our findings support the idea that the ubiquitin-proteasome system plays a role in plant disease defenses.

• 식물조직배양학회지
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• 제27권2호
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• pp.133-136
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• 2000

미생물에서 분리한 dykellic acid가 식물세포에 미치는 생리적 영향을 평가하기 위하여, 담배 광혼용영양배양세포(photomixotrophic cultured cells, PM세포)에 dykellic acid를 다양한 농도로 처리하여 세포의 생장과 단백질 함량 및 superoxide diamutase (SOD)활성에 미치는 영향을 조사하였다. 담배 PM세포는 0.7 mg/L 2,4-D, 0.3 mg/L kinetin, 30g/L sucrose, 200 mM NaCl를 함유한 MS배지에서 $25^{\circ}C$, 광조건에서 현탁배양 (100 rpm) 하였다. 계대배양시 화합물을 처리한 후 12일째의 세포생장 억제와 배지의 이온 전도도를 측정한 세포막손상의 결과는 일치하였으며, 화합물은 세포생장을 강하게 억제시켰다 ($IC_{50}$/, 약 20 $\mu$M). Dykellic acid 처리농도가 증가함에 따라 단위세포 무게당 단백질 함량과 SOD 비활성도를 현저히 증가시켰다. 이상의 결과로 dykellic acid는 식물세포 생장을 저해하는 활성을 가지고 있으며, 담배 PM세포는 적은 양으로도 천연물의 생리활성을 평가할 수 있는 유용한 생물소재임이 확인되었다.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 1998년도 Advances in Ginseng Research - Proceedings of the 7th International Symposium on Ginseng -
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• pp.244-252
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• 1998

Ginsenoside Rh, (G-Rh,) from Panax ginseng induced morphological features of apoptosis and DNA fragmentation as a biochemical marker of apoptosis confirmed by TUNEL reaction and agarose gel electrophoresis in human neuroblastoma SK-N-BE(2) and rat glioma C6Bu-1 cells During apoptosis by G-Rh2, protein kinase C (PKC) isoforms were analysed by immunoblotting. In SK-N-BE(2) cells, the levels of a, p and ${\gamma}$ subtypes were increased by undergoing apoptosis, while PKC e isoform increased early in treatment (3 h and 6 h). In addition, PKC s isoform gradually decreased during apoptosis by G-Rh2 and PKC $\theta$ isoform was detected in neither untreated- nor G-Rh1-treated SK-N-BE(2) cells (data not shown). However, no significant changes in the level of S and s isoforms were observed in C6Bu-1 cells undergoing apoptosis by G-Rh2. These results suggest that PKC subtypes may play differential roles in apoptotic signal pathways and their roles can be cell type-specific in apoptosis induced by G-Rh2.

• 한국연초학회지
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• 제13권2호
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• pp.34-41
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• 1991

To explore the possibility of introducing Zea mays transposable element Ac(activator) which can be used as a mutagen and gene tag in tobacco plants other than maitre, we tried to introduce a cloned Ac element into tobacco cells by an Agrobacterium tumefaciens binary vector system. Transformation of N. babacum cv. Burley 21 tissues and regeneration to whole plant were carried out. The frequency of the transformed callus induced in shoot induction media was higher than that of transformed callus induced in callus induction media. However, the calli were not grown in the second selection media, and became yellow senescent calli. Regenerated tobacco plantlets with foreign gene were also obtained in shoot induction media containing 100 $\mu\textrm{g}$/ml kanamycin and 100$\mu\textrm{g}$/ml carbenicillin. The leaf tissues of transformant was also resistant to 1000 $\mu\textrm{g}$/ml kanamycin. The chromosomal DNAs of transformant and normal plant of N. tabacum were digested by EcoR I and Hind III but not by Pst I.

• Asian Pacific Journal of Cancer Prevention
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• 제16권16호
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• pp.6845-6849
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• 2015

Background: Roles of tobacco and alcohol use in etiology of cancer are well established. Alterationin in P53 have essential roles neoplastic change by preventing genome mutation; the aim of this study was to assess the association between P53 mutation and tobacco and alcohol consumption, as well as to assess the epidemiology of tobacco and alcohol use as risk factors for cancer in the adult population of northern Saudi civilians. Materials and Methods: A cross-sectional survey from October 2014 to January 2015, covering 3,398 adults, was performed. P53 mutation molecular detection was performed for 100 tobacco and alcohol users, usingDNA extracted from buccal cells. Results: Of the 3,398 participants 3,253/3398(95.7%) responded, with a male female ratio of 1.10: 1.00. Out of these, 24.8% had smoked tobacco in their lifetime and 2.7% were consumers of alcoholic beverages. None was identified with any P53 mutation. Conclusions: The prevalence of tobacco smoking among the northern Saudi civilians was relatively high. Females' attitudes in tobacco and alcohol related issues were found to be affected by social stigma. Tobacco and alcohol use has no link to P53 gene mutations.

• 한국연초학회지
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• 제11권2호
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• pp.233-240
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• 1989

This experiment was carried out to select of heterokaryon based on the different buoyant densities of protoplasts. Protoplats were isolated from cultured cells (calli) of Nicotiana tobacum(cv. BY4) and from mesophyll cells of N. glauca. The two types of protoplats were fractionated by centrifugation in an iso-osmotic (770 mOs/kg. H2O) density gradients condition. Major difference in the buoyant density exists between two types of protoplasts isolated from different cells. The mesophyll protoplasts were fractionated in the higher gradient interphases than that of callus protoplasts. The two types of fractionated protoplasts were fused with 40% polyethylene glycol (PEG), and the protoplasts treated with PEG were separated by centrifugation in the same density gradients condition. The heterokaryons were fractionated in the intermediate density gradients.

• 한국연초학회지
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• 제7권1호
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• pp.3-6
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• 1985

The typical dark brown stripe symptom of bacterial wilt disease was observed in the cuttings of tobacco stem treated with the culture filtrate of virulent Pseudomonas solanaceamm. And the tobacco callus create.4 with that culture filtrate showed deterioration of the callus 2 days after the treatment. On the contrary, the cuttings and the callus treated with the culture filtrate of the avirulent bacteria expressed no typical symptom and vigorous growth respectively. Therefore it was suggested that certain toxin which might be produced by the virulent bacteria could break down tobacco cells.

• Journal of Ginseng Research
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• 제43권2호
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• pp.261-271
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• 2019

Background: Protopanaxatriol (PPT) is an aglycone of ginsenosides, which has high medicinal values. Production of PPT from natural ginseng plants requires artificial deglycosylation procedures of ginsenosides via enzymatic or physicochemical treatments. Metabolic engineering could be an efficient technology for production of ginsenoside sapogenin. For PPT biosynthesis in Panax ginseng, damarenediol-II synthase (PgDDS) and two cytochrome P450 enzymes (CYP716A47 and CYP716A53v2) are essentially required. Methods: Transgenic tobacco co-overexpressing P. ginseng PgDDS, CYP716A47, and CYP716A53v2 was constructed via Agrobacterium-mediated transformation. Results: Expression of the three introduced genes in transgenic tobacco lines was confirmed by Reverse transcription-polymerase chain reaction (RT-PCR). Analysis of liquid chromatography showed three new peaks, dammarenediol-II (DD), protopanaxadiol (PPD), and PPT, in leaves of transgenic tobacco. Transgenic tobacco (line 6) contained $2.8{\mu}g/g$ dry weight (DW), $7.3{\mu}g/g$ DW, and $11.6{\mu}g/g$ DW of PPT, PPD, and DD in leaves, respectively. Production of PPT was achieved via cell suspension culture and was highly affected by auxin treatment. The content of PPT in cell suspension was increased 37.25-fold compared with that of leaves of the transgenic tobacco. Transgenic tobacco was not able to set seeds because of microspore degeneration in anthers. Transmission electron microscopy analysis revealed that cells of phloem tissue situated in the center of the anther showed an abnormally condensed nuclei and degenerated mitochondria. Conclusion: We successfully achieved the production of PPT in transgenic tobacco. The possible factors deriving male sterility in transgenic tobacco are discussed.

• Molecules and Cells
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• 제19권3호
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• pp.418-427
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• 2005

When inoculated into sensitive tobacco Xanthi-nn plants, the crucifer and garlic-infecting Tobacco mosaic virus (TMV-Cg) induces local necrotic lesions that resemble those seen in the hypersensitive response (HR) of resistant tobacco plants. However, unlike these, tobacco Xanthi-nn plants do not become resistant to infection and the virus spreads systemically causing a severe disease characterized by necrotic lesions throughout the plant. To identify the viral protein that elicits this necrotic response, we used a set of hybrid viruses constructed by combination of TMV-Cg and the tobacco mosaic virus strain U1 (TMV-U1). In this study we present evidence that the coat protein of TMV-Cg (CPCg) is the elicitor of the necrotic response in tobacco Xanthi-nn plants. Local and systemic necrotic lesions induced by TMV-Cg and by the hybrid U1-CPCg -that carries CPCg in a TMV-U1 context- are characterized by cell death and by the presence of autoflorescent phenolic compounds and $H_2O_2$, just like the HR lesions. In addition, defense-related genes and detoxifying genes are induced in tobacco Xanthi-nn plants after TMV-Cg and U1-CPCg inoculation. We postulate that in our system, CPCg is recognized by sensitive tobacco plants that mount an incomplete defense response. We call this an HR-like since it is not enough to induce plant resistance.