• The Plant Pathology Journal
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• v.17 no.4
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• pp.194-200
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• 2001

Chrysanthemum stunt viroid (CSVd) ws identified in chrysanthemum cv. Chunkwang showing symptoms of stunt with leaf distortion (K1) and stunt with chlorosis of leaves (K2) collected from the main cultivation area of Masan, Kyongnam province in Korea. The specific RNAs related with the diseased chrysanthemums were detected. Full-length 354 bp CSVd cDNAs were amplified from infected tissue by reverse transcription and polymerase chain reaction using a pair of primers specific for CSVd sequence. The amplified cDNA products were analyzed by agarose gel electrophoresis and the specific cDNAs were cloned. Nucleotide sequences of the two CSVd isolates K1 and K2 varied. Phylogenetic analysis of the nucleotide sequences of CSVd isolates indicated that K1 was closely related with J2 and Am 2 isolates. K1 and K2 were transmitted by grafting to Dendranthema grandiflorum cv. Mistletoe, Gynura aurantiaca, and Lycopersicon esculentum cv. Rutgers. This is the first report of CSVd in D. grandiflorum in Korea.

• Korean Journal of Microbiology
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• v.24 no.2
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• pp.86-90
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• 1986

The DNA methylated by Hpa II methylase was not cleaved by Sma, I, Ava I and Nae I endonucleases. This experimental data could be interpreted as strong evidences that Sma I, Ava I and Nae I methylases which yet to be isolated would methylate on the inmost cytosine nucleotide within their hexameric recognition sequences. The facts that Sma I, Ava I and Nae I endonucleases can not cleave the DNA methylated by Hpa II methylase are the valuable informations for protecting DNAs upon cleavage reactions by Sma I, Ava I and NAe I endonucleases especially for cDNA insertion experiments into vector DNAs using Sma I, Ava I and Nae I oligonucleotide linkers. In the case of Xma I endonuclease, partially cleaved DNA fragments were observed although the reaction rate was greatly decreased. This result implies that the methylation site of Xma I methylase which yet to be isolated would not be the same as that of Hpa II methylase in Xma I sequence.

• Biomedical Science Letters
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• v.8 no.3
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• pp.185-188
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• 2002

We have cloned the gene fur long QT syndrome in Korean genome and determined its detailed nucleotide sequence. Blood DNAs were isolated from 68 healthy individuals (including males and females) and the genomic DNAs were amplified by PCR method followed by automatic DNA sequencing. Entire sequence of the coding region for KCNEI was located in exon 3. PCR products were reexamined for the confirmation of KCNE1-specific amplification by nested PCR. KCNE1 mRNA was 436 bp. This corresponded to 129 amino acids. There was no recognizable difference between males and females. This study should contribute to the better understanding of long QT syndrome in Korean population.

• The Journal of Korean Medicine
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• v.27 no.2 s.66
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• pp.225-231
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• 2006

Objectives : This study was performed to determine if unknown species of antler samples could be identified by genetic distance methods. Methods : The DNAs of 4 antler samples were extracted, amplified by PCR, and sequenced. The DNAs of antlers were identified by genetic distance. Genetic distance method was made using MEGA software (Molecular Evolutionary Genetics Analysis, 3.1). Results : By genetic distance methods, all 4 antler samples were closest to Cervus elaphus nelsoni among Cervus species. Conclusion : These results suggest that genetic distance methods might be used as a tool for the identification of Cervus species.

• Microbiology and Biotechnology Letters
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• v.27 no.5
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• pp.364-369
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• 1999

In order to obtain the suitable plasmids for constructing plasmid vectors of Bacillus species, endogeneous plasmid DNAs were screended from thermo-tolerant soil bacteria. Based on agarose gel electrophoresis patterns of the isolated plasmid DNAs, two strains harboring small-size plasmids were selected. The isolated were identified to belong to the genus Bacillus on the basis of their morphological and biochemical properties, and named Bacillus sp. 3-3 and 77-8, respectively. The restriction endonuclease maps were determined for four plasmids including two plasmids from each Bacillus isolates. It is interesting that Bacillus sp. 3-3 and 77-8 have an identical plasmid according to the restriction maps. The three kinds of hybrid plasmids constructed by introducing each plasmid of two isolates into a Escherichia coli plasmid vector. pUCCm18 containing chloramplenicol resistance gene active in Bacillus strains, could be replicated in B. subtilis and B. licheniformis. These plasmids are very stable in B. subtilis, suggesting that the Bacillus plasmids identified in this work would be useful for development of new cloning vectors for Bacillus strains.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.206-206
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• 2006

Polymer induced turbulent drag reduction achieved by adding minute amounts of high molecular weight DNAs in aqueous solution was investigated using a rotating disk apparatus. The DNAs in this study include ${\lambda}-DNA$ and calf-thymus (CT) DNA. By putting emphasis on effect of CT-DNA concentration, its DR characteristics were compared with that of ${\lambda}-DNA$ possessing monodisperse molecular weight characteristics based on both DR efficiency and a mechanical degradation under turbulence. The DNA chains having much higher molecular size than that of ${\lambda}-DNA$ are observed to be more susceptible to mechanical degradation in a turbulent flow. This result was verified via electrophoresis. Furthermore, the coil to globule phase transition of DNA was also investigated under a turbulent flow.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.11a
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• pp.3-8
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• 2005

Torenia hybridacv. Summerwave Blue and Violet mainly produce delphinidin. Down regulation of their flavonoid 3'-hydroxylase and flavonoid 3',5'-hydroxylase (F3'5'H) genes and over expression of rose or pelargonium dihydroflavonol 4-reductase (DFR) cDNA yielded pelargonidin-based bright pink flowers. Nierembergia cv. Fairybells lack pink color as they produced only delphinidin and flavonols. Pelargonidin-based pink flowers were achieved by down regulation of F3'5'H and flavonol synthase genes and over expressing rose DFR cDNA. Introduction of petunia F3'5'H and DFR cDNAs into white carnations deficient in DFR activity produced violet carnations, which arc now commercialized in the USA, Canada, Australia, Europe and Japan. Introduction of pansy F3'5'H and iris DFR cDNAs and down regulation of rose DFR gene produced rose flowers which accumulates delphinidin imparting novel violet color.

• Journal of Photoscience
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• v.8 no.2
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• pp.55-60
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• 2001

Ginseng (Panax genus) is one of the most medicinally important genera and consists of highly regarded medicines. Among the species of Panax, the ginseng species is widely known to have most medicinal quality. P. ginseng has 3 varieties, Jakyung, Chunggyung and Hwangsook, discovered in nature with different colors of stem and fruit, Jakyung has two cultivars, Yunpoong and Chunpoong. Rigorous phylogenetic analysis of these varieties and cultivars has been conducted with sequencing of rDNA region. The sequences of ITS1, ITS2 of every varieties and cultivars within P. ginseng were identical. The sequence of 5.8S rDNAs of Hwangsook variety were different from the sequences of 5.8S rDNAs of others by only one base pair at nucleotide position 14. In phylogenetic analysis and predicted RNA secondary structure study, it is assumed that evolution has proceeded from Hwangsook to other varieties. recently.

• Proceedings of the Korean Aquaculture Society Conference
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• 2002.08a
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• pp.172-174
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• 2002

Out of 20 primers, 6 generated a total of 1,11 major and minor RAPD bands, producing approximately 4.2 average polymorphic bands pe primer in shortnecked clam (Ruditapes philippinarum) population from Anmyeondo. The bandsharing value altered form 0.15 to 0.74, with the average of 0.5, as calculated by bandsharing analysis. The RAPD profiles obtained with DNAs of two populations from Anmyeondo and Seocheon, respectively, were considerably different (0.20 and 0.51, respectively). The varying degrees of difference among populations may also be of relevance to the retricted hybridization of wild bivalve. Besides gene mapping and breeding applications, PCR-RAPD system could be very useful for the rapid certification and quality control of seed production and for every projects based on PCR amplification of specific bivalve DNA fragments.

• Microbiology and Biotechnology Letters
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• v.13 no.3
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• pp.199-201
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• 1985

Plasmids, YEp13 and pMA56, were encapsulated Into liposomes by two different procedures during which the plasmid DNAs were exposed ether to 6$0^{\circ}C$ for 1.5 hr or to sonication for 2-5 min at 4$^{\circ}C$. The encapsulated plasmids were then reextracted and their physical conformations and transformation abilities were examined. It was confirmed from the results that both plasmid DNAs were remained stable throughout the procedures of encapsulation into 1iposomes.