• Korean Journal of Environment and Ecology
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• v.31 no.5
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• pp.461-471
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• 2017

Population genetic studies of 10 groups of Iksookimia pacifica were conducted to investigate the genetic diversity and population genetic structure across its known range in South Korea. Population DNA sequences of one mitochondrial gene (mtCOI) and three nuclear genes (IRBP, EGR2B, RAG1) were examined in samples collected from ten streams that flow into the East Sea. Both mitochondrial and nuclear sequences exhibited significant differentiation among populations except a few cases. The Bayesian analysis of the multi-locus genotypes inferred from the DNA sequences of nuclear genes clustered the individual fish largely into two geographical groups: a northern group (from Baebong stream to Cheonjin stream) and a southern group (Yangyangnamdae stream to Gangneungnamdae stream). Given that the streams flowing into the East Sea are geographically isolated water systems, such separation of genotypes can be interpreted by the geographical separation of common ancestors into north and south that had colonized South Korea. Since the initial geographical separation of the ancestral population by north and south, the ancestral groups seem to have experienced further differentiation into the current genetic clusters through the physical isolation of streams by the East Sea in each region. It is notable that many individuals in the Jasan stream formed a genetic cluster with those of Yangyangnamdae and Gangneungnamdae streams which are distant from each other. In addition, mitochondrial gene showed low genetic differentiation between some neighboring populations and very low level of genetic diversity in several populations. The present population genetic study will provide valuable information for the conservation and management of the Korean endemic fish species, I. paicifica.

• Journal of Life Science
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• v.24 no.9
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• pp.1012-1018
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• 2014

Sasa quelpaertensis Nakai (Korean name, Jeju-Joritdae) is one of the most abundant plants on Mt. Halla, Jeju Island, and it has long been used in traditional medicines. Recent studies have reported it as possessing various beneficial functions, including anti-inflammatory, anti-diabetic, anti-hypertension, anti-gastritis, anti-oxidant, and anti-cancer effects. However, the molecular mechanisms of its anti-cancer activity have not been clearly elucidated. In this study, we investigated the anti-cancer effects and mechanism of S. quelpaertensis on human colon cancer HT-29 cells. Cell growth inhibition by S. quelpaertensis was determined by MTT assay. Apoptosis was performed by DNA fragmentation, flow cytometry with propidium iodide staining (PI), and reverse transcription-polymerase chain reaction (RT-PCR) to confirm the anti-apoptotic factors, such as inhibitor of apoptosis (IAP) family members. $NO^{\bullet}$ production was determined by Griess assay. S. quelpaertensis treatment resulted in the time- and dose-dependent inhibition of the cell viability of HT-29 cells by inducing apoptosis, as evidenced by the accumulation of the sub-G1 cell population stained by PI, as well as the ladder-like DNA fragmentation in a dose-dependent manner. S. quelpaertensis-inducing apoptosis was accompanied by the induction of S cell cycle arrests, increasing $NO^{\bullet}$ concentrations, and the down-regulation of IAPs, including X-chromosome-linked IAP (XIAP), cellular IAP-1 (cIAP-1), cIAP-2, and survivin. Taken together, these findings have important implications for future clinical developments of S. quelpaertensis in colon cancer treatment.

• Korean Journal of Ichthyology
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• v.33 no.4
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• pp.226-239
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• 2021

Sebastes minor, Sebastes trivittatus, Sebastes owstoni, and Sebastes steindachneri are indigenous fish species inhabiting the central part of the East Sea, Korea. In order to understand the molecular evolution of these four rockfishes, we sequenced the complete mitochondrial genomes (mitogenomes) of S. minor and S. trivittatus. To further analyze the phylogeny of Sebastes species, the mitogenomes of 16 rockfishes were comparatively investigated. The complete mitochondrial DNA (mtDNA) nucleotide sequences of S. minor and S. trivittatus were 16,408 bp and 16,409 bp in length, respectively. A total of 37 genes were found in mtDNA of S. minor and S. trivittatus, including 13 protein-coding genes, 2 ribosomal RNA genes, and 22 transfer RNA genes, which exhibited similar characters with other Sebastes species in the East Sea, Korea. In addition, we detected a conserved motif "ATGTA" in the control region of the four Sebastes species, but no tandem repeat units. Comparative analyses of the congeneric mitochondrial genomes were performed, which showed that control regions were more variable than the concatenated protein-coding genes. As a result of analysing phylogenetic relationships of four Sebastes species by using concatenated nucleotide sequences of 13 protein-coding genes, S. minor, S. trivittatus, S. owstoni and S. steindachneri were clustered into three clades. The phylogenetic tree exhibited that S. minor and S. steindachneri shared a closer relationship, whereas S. trivittatus and S. vulpes formed another distinct clade. Our results contribute to a better understanding of evolutionary patterns of Sebastes species inhabiting the middle East Sea, Korea.

• Journal of Korean Society of Forest Science
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• v.102 no.2
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• pp.264-271
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• 2013

Mating system parameters were estimated in a natural population of Pinus koraiensis which was located at Gwongeumseong in Mt. Seorak, South Korea. The estimated parameters from allozyme were as follows: 0.882 of multilocus outcrossing rates($t_m$), 0.881 of singlelocus outcrossing rates($t_s$), 0.368 of correlated paternity($r_p$), and 2.7 of number of effective pollen contributors. The estimated parameters from cpSSR markers were as follows: 0.831 of average of outcrossing rates and 12.4 of the average number of effective pollen contributors. The average outcrossing rate from two genetic markers was 0.857, which was similar to those estimated in other conifer species. More number of potential pollen contributors was estimated from cpSSR marker analysis compared with that estimated from allozyme marker analysis. This result sugges$t_s$ that cpSSR markers may be more useful than allozyme markers for identifying potential pollen contributors in the analysis of mating system.

• Microbiology and Biotechnology Letters
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• v.30 no.1
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• pp.8-14
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• 2002

Pseudomonas sp. S-47 is capable of degrading 4-chlorobenzoate to produce 5-chloro-2-hydroxymuconic semialdehyde (5C-2HMS) by the enzymes encoding by xylXYZLTE cluster. In this study, the resulting 5C-2HMS was confirmed to be transformed to 5-chloro-2-hydroxymuconic acid (5C-2HMA) by 5C-2HMS dehydrogenase. The xylG gene encoding 5C-2HMS dehydrogenase was cloned from the chromosomal DNA of strain S-47. The nucleotide sequence of xylG showed to be composed of 1,600 base pairs with ATG initiation and TGA termination codons. A deduced amino acid sequence of the 5C-2HMS dehydrogenase (XylG) exhibited 98％, 93％, and 89％ identity with those of the dehydrogenases from P. putida mt-2, P. putida G7, and Pseudomonas sp. CF600, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.2
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• pp.103-109
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• 2000

Complete senuences of the mitochondrial rRNA Benes were determined among six salmonines in Korean Waters (Brachpmystax lenok, Onoorhpchus keta, O. masou mason, O. mason ishikawae, O. mykiss, and albino mutant of O. mykiss). The purposes of this study were to provide the basic information on levels of mtDNA polymorphism among these species for genetic characterization; discuss phylogentic relationships among three Oncorhynchus sepecies; demonstrate the utility of rRNA gene sequence data as a genetic marker for disringuishinf among Korean salmonines. PCR/direct sequencing data indicated the following consistent results; 1) 12S rRNA genes was 945 bases long in Oncorhynchus species, and 946 bases in B. lenot including one insertion. 2) Of sequence variation in mitochondrial rRNA regions, transitional substitutions were superior to transversion. 3) The significant differences were not shown in the intraspecific variation values in these gene regions. The percentage sequence divergence values were ranged from $0.066 to 0.212{\%}$. 4) The interspecific divergences were greater than the intraspecific variation. Nevertheless, ribosomal RMh genes were more conserved among species than the other mitochondrial genes, and they showed potentiality as an intergenic marker for systematics. In addition, phylogenetic trees, constructed from this data, supported that cherry salmon was closer to chum salmon than to rainbow trout, and that lenok was most distantly related species in six salmonid species.

• Korean Journal of Microbiology
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• v.51 no.2
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• pp.133-140
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• 2015

We have examined the correlation between the physicochemical and microbiological environment variables for the different layers of oak forest soil in Mt. Gyeryong, Korea. The result shows that there is a high correlation in the environment variables between the soil parameters of the fermented (F) layer and humus (H) layer. In particular, the pH level in the F layer shows a high correlation with C and N, while the various organic acids of the H layer turns out to be closely correlated with soil bacteria density. As we evaluated phylogenetic characteristics of bacterial populations by DGGE analysis with DNA extracted. Total of 175 bands including 43 bands from litter (L) layer, 42 bands from F layer, 43 bands from H layer and 47 bands from rhizosphere (A) layer were selected as the major DGGE band of oak forest soil. Based on the 16S rRNA gene sequences, 175 DGGE bands were classified into 32 orders in 7 phylum. The heat map was analyzed in order to compare the quantity of the base sequences of each order and based on the clustering of the different layers of oak forest soil, the result confirms that the F layer and H layer belong to a different cluster from that of L layer and A layer. Furthermore, it also showed that approximately 50% of the total microbial population in different layers is ${\alpha}$-proteobacteria, which indicates that they belong to the dominant system group. In particular, Rhizobiales, Burkholderiales and Actinobacteriales were observed in all the seasons and layers of oak forest soil, which confirms that they are the indigenous soil bacterial community in oak forest soil.

• Journal of Embryo Transfer
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• v.28 no.4
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• pp.355-360
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• 2013

Precise, rapid and simple methods for species identification in animals are among the most important techniques in the livestock industry and research fields including meat classification. In this study, polymerase chain reaction (PCR) based molecular identification using inter species polymorphisms were examined by PCR-restriction fragment length polymorphism (RFLP) analysis for mitochondrial DNA (mtDNA) cytochrome b (CYTB) gene sequences among four mammalian livestock animals (cattle, horse, goat and pig). The results from PCR-RFLP analysis using the AluI restriction enzyme were also provided for the species-specific band patterns among CYTB gene sequences in these four species. The AluI-digestion for CYTB genes provided interesting migration patterns differentially displayed according to each species. Cattle and horse had one AluI-recognition site at different nucleotide positions and their AluI-digested fragments showed different band patterns on the gels. Pig had two AluI-recognition sites within the amplified CYTB sequences and produced three bands on the gels. Goat had no AluI-recognition site and was located at the same position as the uncut PCR product. The results showed the species-specific band patterns on a single gel among the four livestock animal species by AluI-RFLP. In addition, the results from blind tests for the meat samples collected from providers without any records showed the identical information on the species recorded by observing their phenotypes before slaughter. The application of this PCR-RFLP method can be useful and provide rapid, simple, and clear information regarding species identification for various tissue samples originating from tested livestock species.

• Animal Bioscience
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• v.34 no.4
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• pp.525-532
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• 2021

Objective: Old World camels are a valuable genetic resource for many countries around the world due to their adaptation to the desert environment. At present, Old World camels have encountered the challenge of unprecedented loss of genetic resources. Through our research, we would reveal the population structure and genetic variation in Old World camel populations, which provides a theoretical basis for understanding the germplasm resources and origin and evolution of different Old World camel populations. Methods: In the present study, we assessed mtDNA control region sequences of 182 individuals from Old World camels to unravel genetic diversity, phylogeography, and demographic dynamics. Results: Thirty-two haplotypes confirmed by 54 polymorphic sites were identified in the 156 sequences, which included 129 domestic and 27 wild Bactrian camels. Meanwhile, 14 haplotypes were defined by 47 polymorphic sites from 26 sequences in the dromedaries. The wild Bactrian camel population showed the lowest haplotype and nucleotide diversity, while the dromedaries investigated had the highest. The phylogenetic analysis suggests that there are several shared haplotypes in different Bactrian camel populations, and that there has been genetic introgression between domestic Bactrian camels and dromedaries. In addition, positive values of Tajima's D and Fu's Fs test demonstrated a decrease in population size and/or balancing selection in the wild Bactrian camel population. In contrast, the negative values of Tajima's D and Fu's Fs test in East Asian Bactrian camel populations explained the demographic expansion and/or positive selection. Conclusion: In summary, we report novel information regarding the genetic diversity, population structure and demographic dynamics of Old World camels. The findings obtained from the present study reveal that abundant genetic diversity occurs in domestic Bactrian camel populations and dromedaries, while there are low levels of haplotype and nucleotide diversity in the wild Bactrian camel population.