• Proceedings of the Korean Society of Toxicology Conference
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• 1998.10a
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• pp.55-55
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• 1998

• Proceedings of the Botanical Society of Korea Conference
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• 1998.07a
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• pp.116-116
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• 1998

• BMB Reports
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• v.30 no.4
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• pp.292-295
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• 1997

Exposure of seedling of rice (Oriza sativa cv.Dongin) to cold stress ($6^{circ}C$, 7day) induced differential gene expression. Differentially expressed polyadenylated RNA induced by low temperature were isolated and identified from the leaves of rice (Oriza sativa cv.Dongin) seedling by using the technique, differential display of reverse transcription through polymerase chain reaction (DDRT-PCR). Four bands of cDNAs were differentially displayed on the PAGE gel through DDRT-PCR, and among them three bands were those of overexpressed genes while one band was of an underexpressed gene One of the overexpressed cDNA was characterized. The size of the DDRT-PCR product was found to be about 200 bp. The sequence of the cloned DNA was compared with those of GenBank through a BLAST E-Mail server, and it was found to have no homologies in the nucleotide sequence with that of any known DNA: therefore, it was designated as RC101 The expression of the cold-stress induced-gene, RC101, was sustained with Northern Blot analysis by using the cloned DDRT-PCR product as a probe.

• Journal of Microbiology
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• v.45 no.6
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• pp.534-540
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• 2007

The Streptomyces coelicolor A3(2) genome contains six operons (rrnA to F) for ribosomal RNA synthesis. Transcription from rrnD occurs from four promoters (p1 to p4). We found that transcripts from the p1 and p3 promoters were most abundant in vivo in the early exponential phase. However, at later phases of exponential and stationary growth, transcripts from the p1 promoter decreased drastically, with the p3 and p4 transcripts constituting the major forms. Partially purified RNA polymerase supported transcription from the p3 and p4 promoters, whereas pure reconstituted RNA polymerase with core enzyme (E) and the major vegetative sigma factor ${\sigma}^{HrdB}$ ($E{\cdot}{\sigma}^{HrdB}$) did not. In order to assess any potential requirement for additional factor(s) that allow transcription from the p3 and p4 promoters, we fractionated a partially purified RNA polymerase preparation by denaturing gel filtration chromatography. We found that transcription from the p3 and p4 promoters required factor(s) of about 30-35 kDa in addition to RNAP holoenzyme ($E{\cdot}{\sigma}^{HrdB}$). Therefore, transcription from the p3 and p4 promoters, which contain a consensus -10 region but no -35 for ${\sigma}^{HrdB}$ recognition, are likely to be regulated by transcription factor(s) that modulate RNA polymerase holoenzyme activity in S. coelicolor.

• Journal of Microbiology
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• v.44 no.1
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• pp.11-22
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• 2006

Escherichia coli protein Rho is required for the factor-dependent transcription termination by an RNA polymerase and is essential for the viability of the cell. It is a homohexameric protein that recognizes and binds preferably to C-rich sites in the transcribed RNA. Once bound to RNA, it utilizes RNA-dependent ATPase activity and subsequently ATPase-dependent helicase activity to unwind RNA-DNA hybrids and release RNA from a transcribing elongation complex. Studies over the past few decades have highlighted Rho as a molecule and have revealed much of its mechanistic properties. The recently solved crystal structure could explain many of its physiological functions in terms of its structure. Despite all these efforts, many of the fundamental questions pertaining to Rho recognition sites, differential ATPase activity in response to different RNAs, translocation of Rho along the nascent transcript, interactions with elongation complex and finally unwinding and release of RNA remain obscure. In the present review we have attempted to summarize 'the knowns' and 'the unknowns' of the Rho protein revealed by the recent developments in this field. An attempt has also been made to understand the physiology of Rho in the light of its phylogeny.

• Journal of Photoscience
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• v.7 no.2
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• pp.73-78
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• 2000

To analyze molecular traits determining pigmentation between Pharbitis nill violet and white, Amplified Fragment Length Polymorphism(AFLP) and Differential Display Reverse Transcription(DDRT) experiments were carried out with either genomic DNAs or total RNAs isolated from both plants. Results of AFLP experiment in combination of 8 EcoRⅠ primers with 6 MseⅠ primers showed 41 violet-and 60 white-specific DNA bands. In the subsequent experiment, 22 violet-and 22 white-specific DNA fragments were amplified by PCR with DNAs eluted. The sizes of the fragments range from 200 to 600bp. DDRT using total RNA produced 19 violet-and 17 white-specific cDNA fragments, ranging from 200 to 600bp. The fragments obtained by both AFLP and DDRT had been cloned into pGEM T-easy vector, amplified and subjected to the nucleotide sequence analyses. As a result of Blast sequence analysis, most of them sequenced up to date showed no similarity to any Known gene, while few has similarity to known animal or plant genes. An AFLP clone V6, for example, has a strong sequence similarity to the human transcription factor LZIP-alpha mRNA and a DDRT clone W19 to Solanum tuberosum 3-hydroxy-3-methylglutaryl coenzyme A reductase mRNA.

• Animal cells and systems
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• v.16 no.2
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• pp.95-103
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• 2012

Asbestos exposure has been known to contribute to several lung diseases named asbestosis, malignant mesothelioma and lung cancer, but the disease-related molecular and cellular mechanisms are still largely unknown. To examine the effects of asbestos exposure in human bronchial epithelial cells at gene level, the global gene expression profile was analyzed following chrysotile treatment. The microarray results revealed differential gene expression in response to chrysotile treatment. The genes up- and down-regulated by chrysotile were mainly involved in processes including metabolism, signal transduction, transport, development, transcription, immune response, and other functions. The differential gene expression profiles could provide clues that might be used to understand the pathological mechanisms and therapeutic targets involved in chrysotile-related diseases.

• Molecules and Cells
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• v.46 no.7
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• pp.399-413
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• 2023

cAMP responsive element-binding protein (CREB) is one of the most intensively studied phosphorylation-dependent transcription factors that provide evolutionarily conserved mechanisms of differential gene expression in vertebrates and invertebrates. Many cellular protein kinases that function downstream of distinct cell surface receptors are responsible for the activation of CREB. Upon functional dimerization of the activated CREB to cis-acting cAMP responsive elements within the promoters of target genes, it facilitates signal-dependent gene expression. From the discovery of CREB, which is ubiquitously expressed, it has been proven to be involved in a variety of cellular processes that include cell proliferation, adaptation, survival, differentiation, and physiology, through the control of target gene expression. In this review, we highlight the essential roles of CREB proteins in the nervous system, the immune system, cancer development, hepatic physiology, and cardiovascular function and further discuss a wide range of CREB-associated diseases and molecular mechanisms underlying the pathogenesis of these diseases.

• Journal of applied mathematics & informatics
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• v.26 no.3_4
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• pp.811-818
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• 2008

Biological systems with both protein-protein and protein-gene interactions can be modeled by differential equations for concentrations of the proteins with time-delay terms because of the time needed for DNA transcription to mRNA and translation of mRNA to protein. Values of some parameters in the mathematical model can not be measured owing to the difficulty of experiments. Also values of some parameters obtained in a normal stress condition can be changed under pathological stress stimuli. Thus it is important to find the effective way of determining parameters values. One approach is to use optimization algorithms. Here we construct an optimal system used to find optimal parameters in the equations with nonnegative time delays and apply this optimization result to the Nuclear factor-${\kappa}B$ pathway.

• Journal of Microbiology and Biotechnology
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• v.15 no.5
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• pp.1146-1151
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• 2005

The yeast Candida albicans has a distinguishing feature, dimorphism, which is the ability to switch between two morphological forms: a budding yeast form and a multicellular invasive filamentous form. This ability has been postulated to contribute to the virulence of this organism. Previously, we reported that the yeast-to-hypha transition in this organism is suppressed by farnesoic acid, a morphogenic autoregulatory substance that accumulates in the medium as the cells proliferate. In this study, using a differential display reverse transcription polymerase chain reaction (DDRT-PCR) technique, we have identified several genes induced in C. albicans by farnesoic acid treatment. These observations indicate that farnesoic acid can alter the expressivity of multiple genes, including the DNA replication machinery and cell-cycle-control proteins.