• Journal of Plant Biology
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• 제34권4호
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• pp.261-266
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• 1991

The hairy root was induced form potato tuber disc by infection of a. rhizogenes. The detection of the agropine and mannopine by paper electrophoresis confirmed that induced hairy root was transformed by A. rhizogenes. The activity of peroxidase was the highest at 5 weeks and isozyme pattern of peroxidase revealed 3 cathodic bands and 2 anodic bands and new C4 band(pI 4.6) was observed at 7 weeks after cultivation in hairy root was isoelectric focusing. To study the effect of Ca2+ on cell wall formation in hairy root, channel blocker of Ca2+ was treated. The activity of $\beta$-glucan synthetase II(GS II) related to cell wall synthesis was inhibited by about 50% in diltiazem and flunarizine treatment than that of control, but stimulated in CaCl2 treatment. Therefore these results showed that Ca2+ might be an effective factor in the cell wall formation. The activity of GS II by NaF treatment was increased by about 30%. This result suggested that the activity GS II is changed through phosphorylation process.

• Biomolecules & Therapeutics
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• 제6권4호
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• pp.345-350
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• 1998

The adverse effects of ethanol on cell proliferation have been described for a variety of tissues and cells. In the present study, we investigated whether chronic ethanol intoxication impairs the cell proliferation and DNA synthesis induced by oncogenic $H-ras^{V12}$ - and $v-K-ras^{V12}$-transformed cells. Ethanol treatment inhibited the cell proliferation and the DNA synthesis of control parental fibroblasts in a time- and dose-dependent manner. In contrast, ethanol did not suppress the proliferation of either oncogenic $H-ras^{V12}$ - or $v-K-ras^{V12}$ -transformed fibroblasts. Microinjection of oncogenic $H-Ras^{V12}$ protein induces DNA synthesis and ethanol treatment did not interfere with the DNA synthesis. The antiproliferative toxicity of ethanol was rescued by antioxidants, such as N-acetylcysteine and 4-methlpyrazole. These results indicate that the antiproliferative action site of ethanol toxicity lies upstream or is independent of Ras and ethanol exerts its toxicity through a free radical formation.

• Journal of Microbiology and Biotechnology
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• 제22권1호
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• pp.50-57
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• 2012

Phospholipase C-${\gamma}l$ (PLC-${\gamma}l$) expression is associated with cellular transformation. Notably, PLC-${\gamma}$ is up-regulated in colorectal cancer tissue and breast carcinoma. Because exotoxins released by Clostridium botulinum have been shown to induce apoptosis and promote growth arrest in various cancer cell lines, we examined here the potential of Clostridium difficile toxin A to selectively induce apoptosis in cells transformed by PLC-${\gamma}l$ overexpression. We found that PLC-${\gamma}l$-transformed cells, but not vector-transformed (control) cells, were highly sensitive to C. difficile toxin A-induced apoptosis and mitotic inhibition. Moreover, expression of the proapoptotic Bcl2 family member, Bim, and activation of caspase-3 were significantly up-regulated by toxin A in PLC-${\gamma}l$-transformed cells. Toxin A-induced cell rounding and paxillin dephosphorylation were also significantly higher in PLC-${\gamma}l$-transformed cells than in control cells. These findings suggest that C. difficile toxin A may have potential as an anticancer agent against colorectal cancers and breast carcinomas in which PLC-${\gamma}l$ is highly up-regulated.

• 한국결정학회지
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• 제11권2호
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• pp.89-94
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• 2000

A crystallographic unit cell can be transformed into another one by a 3×3 transformantion matrix. If the determinant of the transformation matrix has a negative value, the newly transformed unit cell becomes a left-handed cell. The best way of transforming the left-handed cell to the right-handed one is to multiply each element of the transformation matrix by-1, and its corresponding transformation matrix must be applied tot he atomic coordinates of a noncentrosymmetric crystal so as to maintain the absolute configuration unchanged. The behaviour of absolute configuration caused by transforming the crystallographic unit cell was examined theoretically and experimentally on the compound (S)-(+)-4-phenyl-1-[4-aminobenzoyl) indoline-5-sulfonyl]-4,5-dihydro-2-imidazolone hydrochloride.

• Journal of Microbiology and Biotechnology
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• 제10권1호
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• pp.115-118
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• 2000

Recombinant plasmids harboring a heterologous gene coding for the enhanced green fluorescent protein (EGFP) were transfected and expressed in Drosophila melanogaster S2 cells. A stable transformation of polyclonal cell populations expressing EGFP were isolated after 4 weeks of selection with hygromycin B. The recombinant EFGP expressed in transformed S2 cells consisted of a molecular weight of 27 kDa. EGFP expression was also confirmed by fluorometric measurement. The maximum EGFP concentration was about 9.3 mg/I. The present findings demonstrate not only the successful stable expression of EGFP in Drosophuila was about 9.3 mgI. The present findings demonstrate not only the successful stable expression of EGFP in Drosophila S2 cells, but also the use of EGFP as a reporter to analyze gene expression, with its potential of a Drosophila cell expression system for recombinant protein production being an alternative to a baculovirus-insect cell expression system.

• The Korean Journal of Physiology
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• 제28권2호
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• pp.233-240
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• 1994

In this study, it was investigated whether immortalized proximal tubule cells transformed with pRSVT could survive through the numerous passages. Results were as follows: 1. The cells transfected with pRSVT formed rapidly growing, multilayered colonies within 2 weeks in a hormone defined medium. Domes were also observed in some of the cultures. 2. r-glutamyl transpeptidase activity was equivalent to that observed in primary renal proximal tubule cell cultures. 3. Transformed cells with pRSVT form tubules in matrigel following 20 passages. 4. Genomic DNA of transformants was digested with either the restriction enzyme Xba or BamH1. A band of approximately 7.5kb was detected with Xba. Three BamH1 bands were detected at approximately 15 kb, 6.5 kb, and 3 kb.

• Biotechnology and Bioprocess Engineering:BBE
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• 제11권2호
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• pp.105-109
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• 2006

A transformed hairy root clone of Scutellaria baicalensis was established following infection with Agrobacterium rhizogenes ATCC15834. Three root clones of S baicalensis were selected by growth habit and baicalin content. The most active strain-the SR-03 clone-was examined for its growth and baicalin content under various culture conditions. The root growth and baicalin content were maximized in a Schenk and Hildebrandt medium supplemented with 4 and 6% sucrose, respectively. The accumulation of baicalin in transformed hairy roots was enhanced through exposure to various elicitors. Elicitation was attained by the addition of methyl jasmonate, salicylic acid, and various concentrations of fungal cell wall elicitors to the medium. The accumulation of baicalin in the elicited cultures ranged from 10.5 to 18.3 mg/g dry weight of the roots, which was 1.5- to 3-fold the amount attained in controls.

• IMMUNE NETWORK
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• 제11권6호
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• pp.390-398
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• 2011

Background: Epstein Barr virus (EBV) infected B cells are transformed into lymphoblastoid cell lines. Some researchers suggested some a few similarities between this process and carcinogenesis. We observed the expression of CD80 and CD86, co-stimulatory molecules on EBV-transformed B cells and changes of CD54 expression after stimulation of CD80 and CD86. Methods: CD80 and CD86 were stimulated using anti-CD80 and anti-CD86 monoclonal antibodies. To assess apoptosis and surface protein expression, flow cytometric analysis was performed. Intracellular signal molecules were evaluated by RT-PCR and immunoblot. Morphology and localization of proteins were examined using inverted or confocal microscope. Results: Cross-linking of CD80 and CD86 induced apoptosis and interfered with proliferation of EBV-transformed B cells, and dispersion of clumped cells. We also examined that their stimulation induced ROS accumulation and reduced CD54 expression. Interestingly, we observed that CD80 and CD86 diminished the expression of CD54 in different methods. Both CD80 and CD86 downregulated activation of focal adhesion kinase. CD80 stimulus inhibited CD54 expression through mainly RhoA inactivation, while CD86 down-regulated Ras and JNK phosphorylation. Conclusion: These results suggest that co-stimulatory CD80 and CD86 molecules, expressed EBV-transformed B cells, may play a role in apoptosis and cell adhesion.

• International Journal of Industrial Entomology and Biomaterials
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• 제9권2호
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• pp.173-181
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• 2004

To delay the onset of apoptosis in the culture, transformed Tn 5B1-4 cells harboring anti-apoptotic genes, bcl-2 and baculovirus p35, have been established and analyzed for their anti-apoptotic ability in suspension culture using spinner flasks. In the suspension culture at agitation speeds of 100 rpm and 200 rpm, the cell growth of cell clone expressing Bcl-2 protein was much higher than other two clones and the maximum cell density of the clone was 6.0 ${\times}$ 10$^{6}$ cells/ml and 6.2 ${\times}$ 10$^{6}$ cells/ml at day three of the incubation. On the other hand, the cell growth of cell clone expressing baculovirus protein P35 was much higher than other two clones in suspension culture at agitation speed of 300 rpm and the maximum cell density of the clone was 6.1 ${\times}$ 10$^{6}$ cells/ml at day three of the incubation. Based on the pattern of genomic DNA laddering and the microscopic observation of apoptotic bodies, the more apoptotic bodies are induced in Tn 5B1-4 control cell clone at higher agitation speed. This result shows that the shear stress can be a main factor in inducing apoptosis in spinner flask culture. At low agitation speed, cell clone expressing Bcl-2 was more effective in delaying the onset of apoptosis than the cell clone expressing P35. On the other hand, at high agitation speed, cell clones expressing baculovirus P35 was more effective in delaying the onset of apoptosis than the cell clone expressing Bcl-2. Therefore, anti-apoptotic genes, bcl-2 and baculovirus p35, can playa distinct role depending on agitation speed in the suspension culture.

• Journal of Plant Biotechnology
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• 제34권3호
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• pp.271-275
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• 2007

엽록체 형질전환된 식물체를 얻으려면 먼저 세포수준에서 모든 엽록체가 형질전환되어야 하는데, 세포내에는 많은 수의 엽록체가 존재하므로, 엽록체 형질전환 벡터가 전이되어 형질전환된 엽록체는 선발배지에서 선택적으로 분열을 계속하고 형질전환되지 않은 엽록체들은 분열을 하지 못하게 되어, 결국 해당 세포내의 모든 엽록체가 형질전환된 상태에 이르게 된다. 따라서 만일 해당 세포내에 엽록체의 수가 적으면 그만큼 효율적으로 엽록체 형질전환을 할 수 있을 것이다. 본 연구에서는 담배의 FtsZ 유전자를 핵형질전환법으로 과잉 발현시킴으로써 엽록체의 분열이 저해되어 엽육세포내에 거대한 엽록체 3-5개를 가진 담배식물체의 엽육조직을 이용하여, 엽록체 형질전환을 한 결과, 엽록체 형질전환 빈도가 약 40% 증가되었다.