• Korean Journal of Ichthyology
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• v.21 no.2
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• pp.76-80
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• 2009

Genetic diversity and genetic structure within the Geum River and Mankyung River populations of the Korean endangered Black shinner (Pseudopungtungia nigra) were assessed by amplified fragment length polymorphism (AFLP). AFLP analysis using five primer combinations generated 447 AFLP bands with 64.1% polymorphism (Geum River 74.6% and Mankyung River 53.6%). The heterozygosities within the two populations were calculated to be 0.170 and 0.104, respectively. Their average genetic diversities are 0.240 and 0.147, respectively. The pairwise Fst value (0.150) indicated distinct genetic differentiation between the two populations. A UPGMA dendrogram based on genetic distance among the individuals revealed a division corresponding to geographical regions, with low genetic variation within the Mankyung River population, and low genetic distance (0.026) between the two populations. Consequently, the two populations may have the same genetic origin The Geum River population will be more suitable than the Mankyung River population for conservation plans to increase the population sizes. Genetic and habitat management will be necessary for the Mankyung River population.

• Journal of Science and Technology Studies
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• v.1 no.1 s.1
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• pp.235-259
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• 2001

This study investigates a variety of dysfunctions and dynamics accompanied with the spread of advanced technology, and predicts the developmental directions of future uncertain society. There are, further, proper countermeasures against dysfunctions discussed. First, different theoretical paradigms concerned with the relationship between seience/technology and society would be comparatively analyzed, and their techno-social implications would be examined. Next, the latest trend of bio-technology and information technology, especially the trend of combination of bio- and information technology, appeared in the progress of Human Genome Project, would be considered. Thirdly, techno-social dysfunctions and far-reaching effects following the development of high-technologies would be analyzed, and realistic alternative plans would be suggested. Through this study, we come to a conclusion that, in order to reduce techno-social dysfunctions to a minimum and enhance their eufunctions, not only 'human' control over technological development should be guaranteed, but also action plan for bridging social gaps should be prepared. In addition, fluent communication and mutual understanding of all concerned, particularly between researcher community, government, and civic sector are required.

• Journal of Ginseng Culture
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• v.3
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• pp.1-10
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• 2021

Panax ginseng (Ginseng or Korean ginseng) is one of the most important medicinal herbs in the world. We made a high-quality whole genome sequence of P. ginseng using 'Chunpoong' cultivar, which is the first cultivar registered in Korea Seed and Variety Service (KSVS) with relatively similar genotypes and superior phenotypes, representing approximately 3 Gbp and 60,000 genes. Genome sequence analyses of P. ginseng and related speciesrevealed the origin of Korean ginseng and the ecological adaptation of 18 Panax species around the world. Korean ginseng and American ginseng (P. quinquefolius) are tetraploid species having 24 chromosome pairs, while the other 16 species are diploid species with 12 chromosome pairs. Panax and Aralia are the closest genera belonging to the Araliaceae family that diverged approximately 8 million years ago (MYA). All Panax species evolved as shade plants adapting to cool climates and low light conditions under the canopy of deep forests from Southeast Asia such as Vietnam to Northeast Asia such as Russia approximately 6 MYA. However, through recurrent ice ages and global warming, most diploid Panax species disappeared due to the freezing winter, while tetraploid P. ginseng may have appeared by allotetraploidization, which contributed to the adaptation to cold temperaturesin Northeast Asian countries including the Korea peninsula approximately 2 MYA. American ginseng evolved by the adaptation of P. ginseng in Northeast America after the intercontinental migration 1 MYA. Meanwhile, most of diploid Panax species survived in high-altitude mountains over 1,600 meters in Southeast Asia because they could not endure the hot temperature and freezing cold. The genome sequence provides good basisto unveil the origin and evolution of ginseng and also supports practical gene chips which is useful for breeding and the ginseng industry.

• Journal of Plant Biotechnology
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• v.44 no.2
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• pp.171-177
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• 2017

A callus-mediated regeneration protocol for sea-milkwort, an endangered coastal plant species in South Korea, is reported here. The explants of in vitro-plantlets generated from a node culture revealed distinguishable responses in callus induction depending on genotype, explant source, light condition, and 2,4-D concentration. Especially, continuous darkness exclusively facilitated callus induction from explants prior to other treatments. The calli initiated on the media with 2,4-D ranging from 0.1 mg/L to 3.0 mg/L in the dark vigorously proliferated when subcultured on the same media in continuous darkness. Given 1.0 mg/L zeatin in addition to darkness to the calli of the 'Pistachio' genotype, normal adventitious shoots were only regenerated from nodular structures that formed earlier from the calli at the frequency of 24.4 percent. Regenerated shoots easily grew into plantlets with roots and green color on a phytohormone-free MS medium under lighted condition, that were used for node culture as plant materials. Node culture effectively multiplied plantlets in accordance with protocol by Bae et al. (2016). Acclimatized plantlet clusters developed mature plant clusters under inland environment, followed by flowering the following April. Results were merged with node culture protocol suggested by Bae et al. (2016), which, as an in vitro propagation system for sea-milkwort, may contribute to natural habitat restoration.

• Journal of Life Science
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• v.14 no.4
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• pp.593-607
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• 2004

The nucleotide sequence for a nuclear-encoded small subunit rDNA (SSU rDNA) was determined for 43 species of the class Dinophyceae, including harmful algae Cochlodinium polykrikoides and Gyrodinium aureolum. These sequences and data analyses were performed by parsimony, distances and maximum likelihood methods in PHYLIP (Phylogenetic Inference Package) version 3.573c. The species Noctiluca scintillans, Gonyaulax spinifern and Crypthecodinium cohnii occupied a basal position within the Dino- phyceae in our analyses. The genera Alexandrium and Symbiodinium were monophyletic (supported by a bootstrap value of >70%), whereas the genera Gymnedinium and Gyrodinium formed polyphyletic nodes, for which bootstrap support was strong (>70%) in the neighbor-joining and maximum likelihood methods except for the PHYLIP parsimony analysis (=59%). The sequence divergence between G. aureolum and G. dorsum/ G. galathenum was the largest at 7.4% (45 bp), whereas G. aureolum and G. mikimotoi showed an extremely low value of genetic divergence of 0.9% (5 bp). The genetic divergence between C. polykrikoides and G. aureolum was a low value of 5.2% (31 bp). In the phylogenetic analysis, the placement of G. aureolum and C. polykrikoides was closer to the genus Gymnodinium than to the genus Gyrodinium, which was supported by a moderate bootstrap value.

• Korean journal of applied entomology
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• v.54 no.4
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• pp.303-310
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• 2015

The diamondback moth, Plutella xylostella, overwinters in some protected areas in Korea. Using a sex pheromone trap, the adults were monitored since the occurrence of the overwintering populations. In Andong, P. xylostella exhibited four adult peaks in a year. Biological characters, such as cold tolerance, insecticide susceptibility, and developmental rate, were analyzed and showed a significant variation among different local overwintering populations. Population genetic variation was assessed with molecular markers, in which the initial high genetic variation among the overwintering populations decreased with the progress of seasons. These results suggests that there may be a significant migration of P. xylostella to decrease the genetic variation among the different local populations that are different in biological characters.

• Korean Chemical Engineering Research
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• v.51 no.6
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• pp.727-732
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• 2013

In this report, we present an inverse opal scaffold that can enhance the chondrogenic differentiation of human adipose-derived stem cells (hADSCs) without drug, gene, or cytokine supplement. Inverse opal scaffolds based on poly(D,L-lactide-co-glycolide) were formed with uniform $200{\mu}m$ pores. Due to uniform pore sizes and well-controlled interconnectivity of inverse opal scaffold, hADSCs were allowed to distribute homogeneously throughout the scaffolds. As a result, high cell density culture with scaffold was possible. Since the hADSCs cultured in inverse opal scaffolds were subjected to limited supplies of oxygen and nutrients, these cells were naturally preconditioned to a hypoxic environment that stimulated the up-regulation of hypoxia-inducible factor-$1{\alpha}$ (HIF-$1{\alpha}$). As a result, apoptotic activity of hADSCs until 3 weeks after initial cell seeding was significantly reduced and chondrogenic differentiation related molecular signal cascades were up regulated (transforming growth factor-beta, phosphorylated AKT, and phosphorylated p38 expression). In contrast, hADSCs cultured with small and non-uniform porous scaffolds showed significantly increased apoptotic activity with decreased chondrogenic differentiation. Taken together, inverse opal scaffold could potentially be used as an effective tool for improving chondrogenesis using stem cells.

• Korean Journal of Medicinal Crop Science
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• v.12 no.6
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• pp.500-507
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• 2004

The establishment of an efficient protocol of plant regeneration from leaf explant cultures of Perilla spp. is reported. Regenerated shoots were obtained from leaf explant cultures on solid MS medium containing different concentrations of cytokinins and auxin. The effect of cytokonin and auxin differed depending on each acession. The combination treatments of high level of cytokinin and low level of auxin was more effective for plant regeneration in Perilla frutescens. The best concentration of sucrose was 3% for regeneration. Of spermidine, spermin and putrescine. treatments, the most effective treatment for plant regeneration was $10\;mg/{\ell}$ spermidine.

• Journal of Life Science
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• v.21 no.3
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• pp.358-367
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• 2011

Soybean is known to contain various phytochemicals that are related to anti-oxidant, anti-inflammatory and anti-obesity effects in mice and humans. The anti-obesity effect of by-product extracts from soybean on the differentiation of 3T3-L1 pre-adipocytes to adipocytes was investigated by suppressing adipocyte differentiation and lipid accumulation with Oil Red-O assay and quantitative PCR. In inducing differentiation of 3T3-L1 pre-adipocytes in the presence of an adipogenic cocktail, isobutylmethylanthine (IBMX), dexamathasone, and insulin, treatment with filtrated soybean soaked water, soybean milk, and soycurd residue from soybean curd processing significantly decreased mRNA expression of obesity-related gene such as PPAR${\gamma}$, Fabp4, and Scd1, adipsin, apolipoprotein (APOE) and adiponectin (ADIPOQ) without any significant cytotoxicity. We also determined the well-known isoflavones in soybean, such as daidzein and genistein, in the by-product extracts. Taken together, we suggest that soybean by-product extract showed anti-obesity effect by suppressing adipocyte related gene expression, and that by-products collected during soybean curd processing may be a good candidate as an ingredient in health care products.

• Journal of Plant Biotechnology
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• v.41 no.3
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• pp.116-122
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• 2014

Total of fifty accessions of Brassica rapa with various morphological characteristics were used for production of double haploid plants though microspore culture in Brassica rapa. Among them, only 30 accessions induced embryos from microspores. The highest efficiency of embryo induction of 1.194 per bud was obtained from IT135449 of turnip type, while 3 accessions of sarson (winter oil) type did not generate embryo. The effect of heat shock periods for embryogenesis was also investigated with 4 accessions (IT135449; Turnip type, IT199710; Chinese cabbage type, IT212886; Pak choi type, IT218043; Summer oil type). The high productions of embryos were observed in IT135449, IT199710 and IT212886 when microspores were pre-cultured to $32^{\circ}C$ for 2 days. In IT218043, high embryogenesis was observed at the 3 days of heat shock treatment. The optimal condition of shoot regeneration for IT199710 was observed in MS medium supplemented with NAA $0.5mg{\cdot}L^{-1}$ and BAP $1mg{\cdot}L^{-1}$. In contrast, the IT135449 and IT212886 were observed high regeneration frequency in MS medium without plant growth regulators. All the plantlets regenerated from microspore-derived embryos have been successfully transplanted to soil, and bud self-pollinated seeds were produced from doubled haploid plants. This indicated that double-haploid genotype was likely generated naturally during embryogenesis process.