• The Microorganisms and Industry
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• v.18 no.3
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• pp.69-74
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• 1992

최근 Okamoto등(18)이 처음으로 VB receptor 유전자인 vbr A의 cloning 및 vbr A의 E. coli 유래의 필수 유전자인 Nus G와의 높은 상동성(36%)으로부터 전사, 번역기구의 필수 유전자로서 가능성의 보고와, Miyake등(19)은 A-factor receptor의 repressor로서의 기능을 보고함에 따라 이들 자기조절인자의 항생물질등 2차 대사산물의 생합성에 있어서 signal전달에 따른 전사조절의 switch on-off 기구 연구에 박차를 가하에 되었으며 본고에서는 VB를 중심으로한 유도인자의 기능면 및 응용면을 소개하고자 한다.

• Proceeding of EDISON Challenge
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• 2017.03a
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• pp.16-26
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• 2017

Auxin response factor (ARF) and Aux/IAA transcriptional repressor family proteins play a major role in auxin's signalling process. Using the GALAXY protein modelling programs, monomer, dimer and oligomer structures of Aux/IAA17 and ARF5 protein were predicted based on the known experimental structures. By analysing the proposed complex structures, key interacting residues on binding site could be determined, and further suggestions for experimental studies were made.

• Proceedings of the Zoological Society Korea Conference
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• 2000.10a
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• pp.238.1-238
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• 2000

No Abstract, See Full Text

• Proceedings of the Korean Biophysical Society Conference
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• 2002.06b
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• pp.51-51
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• 2002

PpsR from the facultative photohetrotroph Rhodobacter sphaeroides is involved in repression of photo system gene expression. SDS-PAGE analysis showed that some portion of PpsR is oxidized so that intra- or inter-disulfide bond is formed between the two cysteins in each subunit. The disulfide bond was reduced by dithiothreitol and the binding activity to puc promoter region was increased.(omitted)

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2006.06a
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• pp.32.1-32.1
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• 2006

• Journal of Microbiology and Biotechnology
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• v.18 no.4
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• pp.639-647
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• 2008

The heat-inducible expression vectors for Corynebacterium glutamicum and C. ammoniagenes were constructed by using the ${\lambda}O_L1$ and the cryptic promoters, CJ1 and CJ4 that express genes constitutively in C. ammoniagenes. Although the promoters were isolated from C. ammoniagenes, CJ1 and CJ4 were also active in C. glutamicum. To construct vectors, the $O_L1$ from the ${\lambda}P_L$ promoter was isolated and fused to the CJ1 and CJ4 promoters by recombinant PCR. The resulting artificial promoters, CJ1O and CJ4O, which have one ${\lambda}O_L1$, and CJ1OX2, which has two successive ${\lambda}O_L1$, were fused to the green fluorescent protein (GFP) gene followed by subcloning into pCES208. The expression of GFP in the corynebacteria harboring the vectors was regulated successfully by the temperature-sensitive cI857 repressor. Among them, C. ammoniagenes harboring plasmid pCJ1OX2G containing GFP fused to CJ1OX2 showed more GFP than the other ones and the expression was tightly regulated by the repressor. To construct the generally applicable expression vector using the plasmid pCJ1OX2G, the His-tag, enterokinase (EK) moiety, and the MCS were inserted in front of the GFP gene. Using the vector, the expression of pyrR from C. glutamicum was tried by temperature shift-up. The results indicated that the constructed vectors (pCeHEMG) can be successfully used in the expression and regulation of foreign genes in corynebacteria.

• Journal of Applied Biological Chemistry
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• v.59 no.3
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• pp.215-220
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• 2016

Abstract Secondary cell wall is the most abundant biomass produced by plants. Plant secondary cell wall is composed of a complex mixture of cellulose, hemicellulose, and lignin. Lignin, a phenolic polymer that hinders the degradation of cell wall polysaccharides to simple sugars destined for fermentation to bio-ethanol. Cell wall biosynthesis pathway-specific biomass engineering offers an attractive 'genetic pretreatment' strategy to improve bioenergy feedstock. Recently, we found a transcription factor, MYB7, which is a transcriptional switch that may turns off the genes necessary for lignin biosynthesis. To gain insights into MYB7 mediated transcriptional regulation, we first established a dominant suppression system in Arabidopsis by expressing MYB7-SRDX. Then we used a transient transcriptional activation assay to confirm that MYB7 suppress the transcription of the lignin biosynthetic gene. Taken together, we conclude that MYB7 function as a repressor of the genes involved in the lignin biosynthesis.

• Journal of Microbiology and Biotechnology
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• v.22 no.8
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• pp.1133-1140
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• 2012

Ribonucleic acid interference (RNAi) inhibits the expression of target genes in a sequence-specific manner, and shows potential for gene knockdown in filamentous fungi, in which the locus-specific gene knockout occurs in low frequency. In this study, the function of the repressor of cellulase expression I (ACEI) was verified in Trichoderma koningii (T. koningii) YC01 through RNAi, and ace1-silenced strains with improved cellulase productivity were obtained. An expression cassette that transcribed the interfering double-stranded RNA (dsRNA) of ace1 was constructed and transformed into T. koningii, and the transformants, in which the expression of ace1 was successfully silenced, were selected. As a result of the ace1 gene silencing, the expression levels of the main cellulase and xylanase genes were elevated, and the enhanced production of total proteins, cellulase, and xylanase was observed in the cultivation. In addition, the down-regulation of ace1 resulted in an increasing expression of xyr1, but no clear variation in the expression of cre1, which suggested that ACEI acted as a repressor of the xyr1 transcription, but was not involved in the regulation of the cre1 expression. The results of this work indicate that ace1 is a valid target gene for enhancing enzyme production in T. koningii, and RNAi is an appropriate tool for improving the properties of industrial fungi.

• Journal of Microbiology and Biotechnology
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• v.17 no.11
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• pp.1898-1903
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• 2007

We attempted to modulate the overall protein expression rate through the addition of a repressor against the araBAD promoter system of Escherichia coli, in which glucose was used as a repressor. Therefore, 0.5% L-arabinose was initially contained as an inducer in culture medium, and either 2% glucose or 2% glycerol was used as a carbon source, and it was found that the expression of recombinant interferon-${\alpha}$ could be observed at the beginning of the batch culture when glycerol was used as a carbon source. However, when glucose was used, the initiation of recombinant interferon-${\alpha}$ expression was delayed compared with that when glycerol was used. Furthermore, when the addition of 0.5% glucose was carried out once or twice after 0.5% L-arabinose induction during DO-stat fed-batch culture, the distributions of soluble and insoluble recombinant interferon-${\alpha}$ were modulated. When glucose was not added after the induction of L-arabinose, all of the expressed recombinant interferon-${\alpha}$ formed an inclusion body during the later half of culturing. However, when glucose was added after induction, the expressed recombinant interferon-${\alpha}$ did not all form an inclusion body, and about half of the total recombinant interferon-${\alpha}$ was expressed in a soluble form. It was deduced that the addition of glucose after the induction of L-arabinose might lower the cAMP level, and thus, CAP (catabolite activator protein) might not be activated. The transcription rate of recombinant interferon-${\alpha}$ in the araBAD promoter system might be delayed by the partial repression. This inhibition of the transcription rate probably resulted in more soluble interferon-${\alpha}$ expression caused by the reduction of the protein synthesis rate.

• International Journal of Oral Biology
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• v.35 no.2
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• pp.69-74
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• 2010

The mu opioid receptor (MOR) has been regarded as the main site of interaction with analgesics in major clinical use, particularly morphine. The repressor element-1 silencing transcription factor (REST) functions as a transcriptional repressor of neuronal genes in non-neuronal cells. However, it is expressed in certain mature neurons, suggesting that it may have complex and novel roles. In addition, the interactions between MOR and REST and their functions remain unclear. In this study, we examined the effects of morphine on the expression of REST mRNA and protein in human neuroblastoma NMB cells to investigate the roles of REST induced by MOR activation in neuronal cells. To determine the effects of morphine on REST expression, we performed RT-PCR, real-time quantitative RT-PCR, western blot analysis and radioligand binding assays in NMB cells. By RTPCR and real-time quantitative RT-PCR, the expression of REST was found to be unchanged by either the MOR agonist morphine or the MOR specific antagonist CTOP. By western blot, morphine was shown to significantly inhibit the expression of REST, but this suppression was completely blocked by treatment with CTOP. In the radioligand binding assay, the overexpression of REST led to an increased opioid ligand binding activity of endogenous MOR in the NMB cells. These results together suggest that morphine inhibits the expression of REST in human neuroblastoma cells through a post-transcriptional regulatory mechanism mediated through MOR.