• Microbiology and Biotechnology Letters
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• v.20 no.4
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• pp.483-490
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• 1992

In order to understand the transfer behavior of a particular gene in water environments, kanamycin resistance ($Km^r$) gene was tracked by Southern hybridization with DNA probe in its conjugal transfer. A $Km^r$ natural bacterial isolate and genetically modified microorganisms (GMMs) constructed from the isolate were used as donor for conjugal transfer of the $Km^r$ gene. The transfer frequencies of the $Km^r$ gene from GMM strains were generally 10 to 100 times higher than those from the natural isolate. The conjugants obtained from GMM strains in LB broth had more plasmids newly appeared, and particularly the conjugants in A Wand FW waters revealed more rearrangement in their plasmids as a function of conjugation time. When plasmids of the conjugants obtained in LB broth were Southern hybridized with DNA probe of the $Km^r$ gene, the $Km^r$ plasmids in the conjugants were detected at the same position of the plasmids in donor cells, in spite of the fact that the plasmids were highly rearranged in conjugant cells. But the $Km^r$ plasmids in the donor of DKI and DKC601, and DKC600 were not identified in the conjugants obtained after 50 h conjugation in AW and after 30 h in AW, respectively. The size of the $Km^r$ plasmids showing hybridization signal were a little changed in the conjugants obtained in A Wand FW waters. Therefore, the method of Southern hybridization with DNA probe was proved to be very specific and useful for tracking of particular genes in water environments.

• Food Science and Industry
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• v.52 no.2
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• pp.153-170
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• 2019

With the breathtaking stride beingmade in the field of biotechnology, biocatalyst research using genetically modified microorganism (GMM) is actively being pursued in food industry. However, domestic food and food additive regulation standards and the number of examination management examples currently used in industry is lacking significantly. Up till now, there are only 6 examples of domestic GMM examination and approval cases for food production purposes and furthermore they are limited to the production of functional sweeteners. Domestically, although GMM is developed as a processing aid (contained use), if they are used in the production of food, the safety of GMM, including environmental safety, is evaluated. Also the produced food or food additives using GMM need to be separately examined and approved as a novel food. On the other hand, imported products produced using GMM need to gain approval for the final product only. Thus the expense and the time to obtain regulatory approval is advantageous for imported products versus domestically produced products. This commentary is written to create the opportunity to reform the current domestic food GMM regulation by comparing and discussing domestic and foreign case analyses of safety evaluation of GMM and related regulations.

• Agrochemical news magazine
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• v.22 no.6 s.169
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• pp.22-23
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• 2001

만일 미국인 소비자들에게 식품과 농산물에 생명공학을 적용하는 것을 지지하느냐고 물으면 그들 중 약 $70\%$는 ''그렇다''고 답할 것이다. 하지만 질문의 각도를 좀 달리해서 ''당신은 유전자변형식품(GMO)을 먹어도 된다고 생각하는가''라고 묻는다면 3분의 2가량은 ''아니다''고 대답할 것이다. 하지만 이 두가지 질문은 사실상 같은 것이다. 다만 두번째 질문속의 ''유전자''와 ''변형'' 같은 말들이 수백만명의 소비자들의 경계심리를 자극하는 것이다. GMO 기술은 적절하게만 사용된다면 식품의 영양을 개선하고 농업생산량을 증대시켜 농가소득을 높이고 심지어 환경적 위해 요소를 줄일 수 있다. 하지만 이 기술이 현재 부적절하게 시험되고 잘못 적용되는 등 불완전하게 규제될 경우 영양학적으로나 환경적으로 큰 위해로 작용할 수 있다. 따라서 이에 대한 정확한 이해와 득실을 알아 둘 필요가 있다.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05d
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• pp.40-45
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• 1996

사람 T-임파구에서 방사선 독성물질인 감마선과 화학적 독성물질인 PCP(pentachlorophenol)의 돌연변이 효과를 hprt (hypoxanthine phosphoribosyl transferase) 유전자의 돌연변이빈도로써 측정하였다. 감마선은 $^{137}$Cs원을 사용하여, 0 - 300 rads의 양으로 세포의 초기배양 시기에 조사하였으며, PCP는 역시 세포의 초기배양시 최종농도 0-100 ppm으로 24시간 투여 하였다. 양 돌연변이원은 hprt유전자를 돌연변이 시키어, 300rads의 조사는 대조군에 비하여 약 7.5배의 돌연변이빈도의 증가를 나타내었고, PCP 500 ppm의 처리는 대조군에 비하여 약 5배의 돌연변이빈도 증가를 나타내었다. 본 실험에 사용된 상이한 두 돌연변이원은 모두 비교적 정확한 용량-반응 관계를 보였으나, 환경독성물질들의 혼합효과에서 돌연변이원을 정성하기위하여 개선된 T-cell hprt clonal assay, 즉 reverse transcriptase/polymerase chain reaction 및 direct sequencing에 의한 mutational spectrum의 적용이 요구되었다.

• Journal of fish pathology
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• v.10 no.1
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• pp.39-44
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• 1997

Metallothionein is an important and essential protein to control the intracellular concentration of heavy metals, which exist in all organisms from bacteria to vertebrates. Although the detailed functions and induction mechanisms of metallothionein gene have not been clearly characterized until yet, the structure of several metallothionein genes has been revealed. Especially, piscine metallothionein is regarded as an important protein because it is induced by several heavy metal pollutants and environmental stress and it could be determined the comparative amount of heavy metals and the extent of environmental stress by assaying the RNA transcript of metallothionein gene in the method of the quantitative RT-PCR(Reverse Transcriptase Polymerase Chain Reaction). In this study I have characterized the 450 bp PCR fragment of metallothionein gene amplified by using the mixture of internal specific primers and universal 3' end primer. The nucleotide sequence analysis of 450 bp PCR fragment amplified in cDNA library of channel catfish did not show strong homology to other piscine metallothionein genes.

• Korean journal of applied entomology
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• v.54 no.4
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• pp.335-343
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• 2015

One of the primary concerns about the environmental risks of genetically modified (GM) crops is that they may have adverse effects on the local arthropod communities. In this study, we investigated whether the arthropod diversity and community structure in fields of GM rice tolerant to protoporphyrinogen oxidase (PPO)-inhibiting herbicides differ from those in non-GM (control) rice fields. The aim of this study was to assess the potential adverse effects of GM rice on the local arthropod communities. During the growing seasons in the study period, we collected arthropods from both fields by using yellow sticky traps and compared the diversity and community structure of arthropods from the two sites. Overall, the GM rice had no significant effect on the diversity of the local arthropod communities. In addition, multivariate analyses (permutational multivariate analysis of variance and nonmetric multidimensional scaling) showed that the structures of arthropod communities were not affected by the rice genotype (GM vs. non-GM), although these comparisons were made using data obtained at different sampling dates.

• Korean Journal of Environmental Biology
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• v.22 no.3
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• pp.472-477
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• 2004

To study the radiation related gene expression in mutants of Bacillus lentimorbus WJ5 induced by gamm radiation, the simultaneous gene expression was analyzed by DNA micro array. We constructed DNA chips including two thousand randomly digested genome spots of B. lentimorbus WJ5 and compared its quantitative aspect with seven mutants induced by gamma radiation $(^{60}/Co)$. From the cluster analysis of gene expression pattern, totally 408 genes were expressed and 27 genes were significantly upregulated by the gamma radiation in all mutants. Especially, genes involved in repair (mutL, mutM), energy metabolism (acsA, sdhB, pgk, yhjB, citB), protease (npr), and reduction response to oxidative stress (HMM) were simultaneously upregulated. It seems that the induction of the direct and/or indirect repair related genes in mutants induced by gamma radiation could be remarkably different from the adaptive responses against acute exposure to radiation.

• Journal of Life Science
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• v.27 no.12
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• pp.1415-1420
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• 2017

The metallothionein (MT) gene (IbMT3) was selected from an EST library of suspension-cultured sweet potato cells. The MT gene, which is one of abundant ESTs in the library, is involved in stress regulation of cells and tissues. A full-length IbMT3 cDNA was obtained and analysis of its nucleotide sequence revealed that IbMT3 encoded a type 3 MT protein, based on its structural characteristics. The function of type 3 MT in plants is not yet known. Northern blot analysis showed stronger expression of IbMT3 in suspension-cultured cells than in sweet potato plant leaves. Since cell culture is known to impose a state of oxidative stress on cells, sweet potato plants were subjected to oxidative stress to investigate the transcriptional regulation of IbMT3. When the herbicide methyl viologen (MV) was administered for 6, 12, and 24 hr, IbMT3 transcription rapidly increased at 6 hr and then decreased. A cold treatment at $15^{\circ}C$ for 24 and 48 hr resulted in a gradual increase in IbMT3 expression. These findings indicate that IbMT3 expression is regulated in response to environmental and oxidative stress. IbMT3 isoform is expected to have antioxidant effects in sweet potato plants and may play an important role in cellular adaptation to oxidative stress.

• FLOWER RESEARCH JOURNAL
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• v.19 no.4
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• pp.269-273
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• 2011

This study was conducted to investigate the resistance to abiotic stress in the progeny obtained by a cross between NDPK2-transgenic line (NDPK2-7-1) and MnSOD (SOD2) transgenic line (SOD2-2-1-1-35) to develop transgenic petunia highly resistant to environmental stress. At the treatment of 100 and $200{\mu}M$ methyl viologene (MV), the progeny was significantly less damaged than its parental plants (SOD2- or NDPK2-transgenic lines) as well as non-transgenic plants, implying its resistance to oxidative stress enhanced than SOD2- or NDPK2-transgenic plants. In an expression of 11 quantitative traits, the progeny remained similar to control plants, although it infrequently displayed slightly longer or wider than non-transgenic control plants. In the color and shape of flowers, there was no significant difference between the progeny and its parents or non-transgenic control.

• Journal of Marine Life Science
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• v.6 no.2
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• pp.97-105
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• 2021

Tegillarca granosa, is one of the most important fishery resources throughout Asia. However, due to industrialization factories, marine environmental pollution, and global warming, the marine fishery production has drop sharply. In order to understand the genetic factors of the blood clam, which is a major fishery resource on the southern coast of Korea, the whole genome of blood clam was studied. The assembled genome of T. granosa was 915.4 Mb, and 19 chromosomes were identified. 25,134 genes were identified, and 22,745 genes were functionally annotated. As a result of performing gene gain and loss analysis between the blood clam genome and eight other types of shellfish, it was confirmed that 725 gene groups were expanded, and 479 gene groups were contracted. The homeobox gene cluster of blood clam showed a well-preserved genetic structure within lophotrochozoan ancestor. T. granosa genome showed high similarity between three hemoglobin genes with Scarpharca broughtonii. The blood clam genome will provide information for the genetic and physiological characteristics of blood clam adaptation, evolution, and the development of aquaculture industry.