• Journal of Microbiology and Biotechnology
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• v.18 no.2
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• pp.228-233
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• 2008

Effects of chaperones on mRNA stability and gene expression were studied in order to develop an efficient Escherichia coli expression system that can maximize gene expression. The stability of mRNA was modulated by introducing various secondary structures at the 5'-end of mRNA. Four vector systems providing different 5'-end structures were constructed, and genes encoding GFPuv and endoxylanase were cloned into the four vector systems. Primer extension assay revealed different mRNA half-lives depending on the 5'-end secondary structures of mRNA. In addition to the stem-loop structure at the 5'-end of mRNA, coexpression of dnaK-dnaJ-grpE or groEL-groES, representative heat-shock genes in E. coli, increased the mRNA stability and the level of gene expression further, even though the degree of stabilization was varied. Our work suggests that some of the heat-shock proteins can function as mRNA stabilizers as well s protein chaperones.

• Microbiology and Biotechnology Letters
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• v.17 no.2
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• pp.160-164
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• 1989

A 5.7Kb EcoRI fragment containing alkaline amylase gene of Bacillus sp. AL-8 obtained in the previons experiment (10) was transformed in B. subtilis via plasmid pUB110. The enzymatic proper-ties of the amylase produced by the transformants were Identical to those of the donor strain. Thus, the alkaline amylase activity from the transformant was maximum at pH 10 and 5$0^{\circ}C$. And the enzyme was very stable over the ranges of alkaline pH. In order to determine the location of the alkaline amylase gene within the 5.7Kb DNA fragment, the fragment was subcloned in E. coli. It was found that the alkaline amylase gene was located k EcoRI fragment of 3.7Kb.

• Journal of the Korean Data and Information Science Society
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• v.20 no.1
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• pp.171-178
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• 2009

In order to make the high quality Korean cattle, it has been identified the gene which influence to various economic characters. In this paper, we introduce Restricted Partition Method for gene-gene interaction analysis. Further, economic traits, longissimus muscle dorsi area (LMA), carcass cold weight (CWT) and average daily gain (ADG) are applied with Restricted Partition Method (RPM). The SNP (19_1)$^*$SNP (28_2) was selected and was best marker on Single nucleotide polymorphisms (SNPs). It also influenced SNP (19_1)$^*$SNP (28_2) was an very important marker for economic character and to make the thing know it became.

• Biomedical Science Letters
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• v.16 no.4
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• pp.299-305
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• 2010

KCNE1 is the causal gene of long QT syndrome. KCNE1 gene is located in chromosome 21. In compliance with this KCNE1 gene the proteins come out. KCNE1 is responsible for $K^+$ channel which maintains the normal function of the heart muscle for contraction. Affected individuals manifest prolongation of the QT interval on electrocardiongrams, a sign of abnormal cardiac repolarization. The clinical features of LQT result from episodic cardiac arrhythmias, such as torsade de pointes and ventricular fibrllation. Blood DNA was isolated and kept in $4^{\circ}C$ refrigerator. The KCNE1 gene was amplified by PCR method and about 414 bp band was identified by agarose gel electrophoresis. PCR products were inserted into pGEX-4T-1 vector in order to express KCNE1 protein after treatment with IPTG SDS-PAGE was carried out and the protein band which was about 47 kDa was clearly odserved. Results of this study would contribute to the detailed understanding of KCNE1 protein function and to designing better treatment of Long QT symdrome.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.10
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• pp.1044-1049
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• 2006

Multiple sequence alignment is a method to compare two or more DNA or protein sequences. Most of multiple sequence alignment tools rely on pairwise alignment and Smith-Waterman algorithm to generate an alignment hierarchy. Therefore, in the existing multiple alignment method as the number of sequences increases, the runtime increases exponentially. In order to remedy this problem, we adopted a parallel processing suffix tree algorithm that is able to search for common subsequences at one time without pairwise alignment. Also, the cross-matching subsequences triggering inexact-matching among the searched common subsequences might be produced. So, the cross-matching masking process was suggested in this paper. To identify the function of the clusters generated by suffix tree clustering, BLAST and CDD (Conserved Domain Database)search were combined with a clustering tool. Our clustering and annotating tool consists of constructing suffix tree, overlapping common subsequences, clustering gene sequences and annotating gene clusters by BLAST and CDD search. The system was successfully evaluated with 36 gene sequences in the pentose phosphate pathway, clustering 10 clusters, finding out representative common subsequences, and finally identifying functional domains by searching CDD database.

• Proceedings of the Korean Statistical Society Conference
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• 2005.11a
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• pp.31-36
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• 2005

An identification and characterization of susceptibility genes for common complex multifactorial diseases is a challengeable task, in which the effect of single genetic variation will be likely dependent on other genetic variations(gene-gene interaction) and environmental factors (gene-environment interaction). To address is issue, the multifactor dimensionality reduction (MDR) has been proposed and implemented by Ritchie et al. (2001), Moore et al. (2002), Hahn et al.(2003) and Ritchie et al. (2003). With MDR, multilocus genotypes effectively reduce the dimension of genotype predictors from n to one, which improves the identification of polymorphism combinations associated with disease risk. However, MDR cannot handle missing observations appropriately, in which missing observation is treated as an additional genotype category. This approach may suffer from a sparseness problem since when high-order interactions are considered, an additional missing category would make the contingency table cells more sparse. We propose a new MDR approach with minimum loss of sample sizes by considering missing data over all possible multifactor classes. We evaluate the proposed MDR by using the prediction errors and cross validation consistency.

• Journal of Sericultural and Entomological Science
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• v.40 no.2
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• pp.105-110
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• 1998

The baculovirus egt gene encodes an ecdysteroid UDP-glucosyltransferase(EGT) which catalyzes the transfer of glucose from UDP-glucose to the insect moltion hormone ecdysteroid resulting in a functionally inactive ecdysteroid. In baculovirus-infected insect larvae, EGT has been shown block molting and pupation. In this study, we compared the development of 4th and 5th instar silkworm, Bombyx mori, larvae injected with either wild-type bombyx mori nucleopolyhedrovirus (BmNPV) or a mutant BmNPV(BmEGTZ) in which the egt gene was disrupted by the insertion of a lacZ gene cassette. Larvae injected with BmEGTZ died roughly 12 h more rapidly compared to indentical larvae infected with BmNPV. In addition, BmEGTZ- infected larvae prematurely stopped feeding and gain less weight compared to BmNPV-infected larvae. In order to investigate why BmEGTZ-infected larvae died more rapidly than BmNPV-infected larvae, the array of hemolymph proteins in BmEGTZ-or BmNPV-infected larvae were analyzed by SDS-PAGE. The hemolymph of BmEGTZ-infected larvae showed virus-specific proteins, including polyhedrin, about 12 h earlier than the hemolymph of BmNPV-infected larvae

• Korean Journal of Plant Tissue Culture
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• v.25 no.5
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• pp.323-327
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• 1998

The flavonoid biosynthetic pathway has been studied as a genetic model system, particularly in Petunia hybrida. In order to study the flavonoid biosynthetic pathway, we constructed a fusion gene system between Cauliflower Mosaic Virus (CaMV) 35S promoter and eggplant flavonoid 3', 5'-hydroxylase in pBI 121 plasmid. An optimal condition for plant regeneration was observed when internode explants were cultured on MS medium supplemented with IAA 0.2 mg/L plus BA 3 mg/L. For plant transformation internode explants of Petunia hybrida were precultured on BM medium supplemented with IAA 0.2 mg/L plus BA 3 mg/L. Putative transgenic plants were selected on medium containing kanamycin 50 mg/L plus cefotaxim 300 mg/L. Putative selected transformants were confirmed by amplification of selectable marker gene (nptII) by polymerase chain reaction (PCR) and Southern hybridization of flavonoid 3',5'-hydroxylase gene.

• Journal of Plant Biotechnology
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• v.4 no.2
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• pp.71-76
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• 2002

In order to achieve repetitive somatic embryogenesis in cacao (Theobroma cacao L.), callus derived from floral tissues were continuously cultured in a medium containing 2,4-D. In 5% of the explants, repetitive somatic embryogenesis was observed after 8 weeks and maintained in a globular stage for several weeks. This is the first report showing repetitive somatic embryogenesis in cacao. The calli were bombarded with a plasmid containing $\beta$-glucuronidase (gus) as reporter gene. Two week old calli showed the high average number of cells expressing the us gene. The effect of osmotic agents (mannitol, sorbitol and sucrose) on gene expression was evaluated. Pre-treatment during 16 h with 0.25 M mannitol revealed an improvement in gene expression. The potential utilization of the repetitive embryogenesis, combined with osmotic treatment, is discussed as an alternative to achieve stable transgenic cacao plants.

• Journal of Microbiology and Biotechnology
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• v.5 no.1
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• pp.6-13
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• 1995

A gene coding for the $\beta$-galactosidase (lactase) of Kluyveromyces tragilis UCD 55-55 was isolated by complementation in Escherichia coli YMC9. From the plasmid library made from Sau3A-digested chromosomal DNA, one positive clone was selected. The cloned gene for $\beta$-galactosidase was on 7.3 kilobase pair DNA fragment, and a slightly low level of $\beta$-galactosidase enzyme activity was detecied in E. coli. It was also confirmed that the cloned gene comes from K. tragilis by DNA-DNA hybridization and immunochemical blotting experiments. In order to construct a new yeast strain having the metabolic ability for lactose, the cloned gene for K. tragilis $\beta$-galactosidase was inserted in yeast vector YEp24 and YRp17, and transformed into Saccharomyces cerevisiae YNN27 and Ml-2B. The yeast transformants showed the nearly the same $\beta$-galactosidase productivity as level of K. tragilis when uninduced, but these could not utilize lactose as a sole carbon source, presumably due to the lack of lactose transport system. Nevertheless, a slightly higher ethanol productivity was achieved by these transformants than S. cerevisiae or K. tragilis, in the medium containing glucose and lactose.