• IMMUNE NETWORK
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• v.23 no.1
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• pp.5.1-5.28
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• 2023

Th cell lineage determination and functional specialization are tightly linked to the activation of lineage-determining transcription factors (TFs) that bind cis-regulatory elements. These lineage-determining TFs act in concert with multiple layers of transcriptional regulators to alter the epigenetic landscape, including DNA methylation, histone modification and threedimensional chromosome architecture, in order to facilitate the specific Th gene expression programs that allow for phenotypic diversification. Accumulating evidence indicates that Th cell differentiation is not as rigid as classically held; rather, extensive phenotypic plasticity is an inherent feature of T cell lineages. Recent studies have begun to uncover the epigenetic programs that mechanistically govern T cell subset specification and immunological memory. Advances in next generation sequencing technologies have allowed global transcriptomic and epigenomic interrogation of CD4+ Th cells that extends previous findings focusing on individual loci. In this review, we provide an overview of recent genome-wide insights into the transcriptional and epigenetic regulation of CD4+ T cell-mediated adaptive immunity and discuss the implications for disease as well as immunotherapies.

• Journal of Microbiology and Biotechnology
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• v.16 no.3
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• pp.423-430
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• 2006

A total of 367 isolates of Phytophthora infestans was collected from the leaf samples of late blight disease from five provinces in Korea over the three growing seasons of 2002-2004. Of the 367 isolates, 337 isolates were of the A1 mating type, and 30 isolates were of A2 mating type, showing that the majority was A1 mating type. Profiles of Gpi and Pep defined four allozyme genotypes among the total of 367 isolates. All four allozyme genotypes could be distinguished on the basis of Gpi profiles alone, whereas all isolates were homozygous at the Pep locus (100/100). The mitochondrial DNA haplotype of all isolates were the IIa haplotype. Amplification of the genomic DNAs extracted from eight isolates of each mating type by polymerase chain reaction with the selected primer (OPC-5 primer) produced a total of 20 DNA bands, of which 11 bands were polymorphic. According to the RAPD analysis using the OPC-5 primer, 106 isolates including two standard isolates were separated into 8 groups at the similarity level of 92.5%. The RAPD groups were not correlated with the allozyme genotypes and the isolated locations. All of the eight RAPD groups were identified in Gangwon-do, suggesting that Gangwon-do is the center of origin of the P. infestans in Korea. A 600-bp DNA band generated with the OPC-5 primer was specific to A1 mating type isolates, but not detected with A2 mating type, showing that the specific PCR primer can distinguish different mating types in P. infestans.

• Horticultural Science & Technology
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• v.32 no.2
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• pp.210-216
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• 2014

The distribution of S-haplotypes and genetic relationships were evaluated for 47 accessions of 'Danji' radish (Raphanus sativus L. var. hortensis Baker f. gigantissimus Makino) originating from Jeju Island in South Korea. A total of 22 S-haplotype-specific SCAR markers for the S locus glycoprotein (SLG) and S receptor kinase (SRK) loci were tested, and six primer sets amplified locus-specific PCR fragments from at least one 'Danji' radish accession. S5 and S21 alleles atthe SLG locus were the most frequently distributed, and detected from 87.5% and 64.6% of the accessions, respectively. The frequency of the class-II haplotype at the SLG locus was 75%, more frequent than the class-I haplotype. The S23 allele at the SRK locus was detected from 7 accessions. Grouping of the accessions based on S-allele composition revealed three major groups, while 8 accessions showed a unique allelic composition. The genetic diversity of 47 'Danji' radishes and 1 'Gwandong' radish were also evaluated with 38 RAPD primers. A total of 312 bands were scored, and showed that 138 bands (44.2%) were monomorphic among the accessions, whereas 174 (55.8%) bands were polymorphic. Polymorphism rates ranged from 0.2 to 1.0, indicating significant variations in detecting polymorphism across RAPD primers. The genetic similarity coefficients among all pairs of the 48accessions varied from 0.62 to 0.93, and 42% of the comparisons exhibited values higher than 0.85. All the cultivars could be distinguished based on the DNA fingerprints revealed by RAPD. The comparisons between the dendrograms based on S-haplotypes and RAPDs indicate an unrelated and sporadic distribution for several accessions; however, there was a tendency for accessions with the same S-allelic composition to group into the same cluster.

• Parasites, Hosts and Diseases
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• v.52 no.6
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• pp.631-637
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• 2014

Genetic characteristics of Plasmodium falciparum may play a role in the treatment outcome of malaria infection. We have studied the association between diversity at the merozoite surface protein-1 (msp-1), msp-2, and glutamate-rich protein (glurp) loci and the treatment outcome of uncomplicated falciparum malaria patients along the Thai-Myanmar border who were treated with artemisinin derivatives combination therapy. P. falciparum isolates were collected prior to treatment from 3 groups of patients; 50 cases of treatment failures, 50 recrudescences, and 56 successful treatments. Genotyping of the 3 polymorphic markers was analyzed by nested PCR. The distribution of msp-1 alleles was significantly different among the 3 groups of patients but not the msp-2 and glurp alleles. The allelic frequencies of K1 and MAD20 alleles of msp1 gene were higher while RO33 allele was significantly lower in the successful treatment group. Treatment failure samples had a higher median number of alleles as compared to the successful treatment group. Specific genotypes of msp-1, msp-2, and glurp were significantly associated with the treatment outcomes. Three allelic size variants were significantly higher among the isolates from the treatment failure groups, i.e., $K1_{270-290}$, $3D7_{610-630}$, $G_{650-690}$, while 2 variants, $K1_{150-170}$, and $3D7_{670-690}$ were significantly lower. In conclusion, the present study reports the differences in multiplicity of infection and distribution of specific alleles of msp-1, msp-2, and glurp genes in P. falciparum isolates obtained from treatment failure and successful treatment patients following artemisinin derivatives combination therapy.

• Animal cells and systems
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• v.13 no.2
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• pp.179-186
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• 2009

Discriminating between eel species of the genus Anguilla using morphological characteristics can be problematic, particularly in the glass eel and elver stages. In this study, sequence-characterized amplified region (SCAR) and polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) markers were developed for the identification of Anguilla japoniea, Anguilla btcoior bicaor. Anguilla rostrata, and Anguilla anguilla. Random amplified polymorphic DNA (RAPD) fragments from A. japoniea (362 bp), A. bicolor bicctor (375 bp), A. rostrata (375 bp), and A. anguilla (375 bp) were isolated, sequenced, and converted to SCAR markers. The principal difference between the SCARs of A. japoniea and the three other species is the absence of a 13 bp deletion in the A. japoniea SCAR. Specific PCR primers amplified a 290 bp fragment for A. japoniea and 303 bp fragments for A. bicolor bicoior. A. rostrata, and A. anguilla. Restriction enzyme digestion with Taql, Mael, and Tru9l yielded PCR-RFLP patterns with differences that, when analyzed together, are sufficient for distinguishing each of the four eel species. In addition, RAPD fragments for A. japoniea (577 bp), A. bicoior bicoor (540 bp), A. rostrata (540 bp), and A. anguilla (509 bp) were also isolated and sequenced. The A. japoniea, A. bicoior blcoior. A. rostrata, and A. anguilla PCR products contain ten, nine, nine, and eight tandem repeats, respectively, of a 37 bp sequence. These results suggest that SCAR and PCR-RFLP markers and repeat numbers for specific loci will be useful for the identification of these four Anguilla eel species.

• Korean Journal of Plant Taxonomy
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• v.40 no.2
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• pp.118-129
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• 2010

A taxonomic study of Viola albida complex, containing the representative individuals of three taxa, V. albida var. albida, V. albida var. chaerophylloides, and V. albida var. takahashii, was done based on RAPD data. The amplified loci were 476 in total; obtained with 68 universal primers on seven OTUs. Nei's genetic dissimilarity appeared relatively low within individuals of V. albida var. albida and V. albida var. chaerophylloides (0.118-0.171 and 0.051 respectively), however, it was higher in individuals of V. albida var. takahashii (0.348). On the other hand, there is no specific trend in terms of genetic dissimilartiy among taxa, such as between individuals of V. albida var. albida and V. albida var. takahashii, between those of V. albida var. albida and V. albida var. chaerophylloides, and between those of V. albida var. albida and V. albida var. takahashii. The similarity of OTUs studied is high in clustering analysis, so that this result is compatible with the establishment of this complex. All OTUs are clustered within two groups. The individuals of V. albida var. takahashii, however, are clustered both to the group of V. albida var. albida and to the group of V. albida var. chaerophylloides, meaning that the genetic difference is high which would be commensurate with their morphological variations.

• Food Science of Animal Resources
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• v.27 no.2
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• pp.150-156
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• 2007

This study was conducted to analyze the genetic characteristics of Korean Native Pigs(KNP), and to establish an individual identification system comprising many microsatellite markers located on different pig autosomes. Genotype data from 13 microsatellites typed in 446 animals was used to determine the validation of a method of individual identification in 4 KNP. A total of 112 alleles of the 13 microsatellites were detected and average heterozygosities(polymorphic information content) ranged from 0.286(0.423) to 0.686(0.796) in this study. Comparing the pattern of allele frequency among the KNP, Yorkshire, Landrace and Duroc breeds, there was specific differentiation between populations at multi-allelic loci. The cumulative power of discrimination(CPD) was 99.999% by including 10 microsatellite loci for the individual identification system. The probability that two different individuals incidentally have same genotype was estimated to be $0.36{\times}10^{-9}$. The system employing these 10 markers therefore proved to be applicable to the individual identification of KNP.

• Journal of Ginseng Research
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• v.35 no.1
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• pp.52-59
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• 2011

Recently, new ginseng cultivars having superior agricultural traits have been developed in Korea. For newly developed plant cultivars, the identification of distinctiveness is very important factors not only in plant cultivar management but also in breeding programs. Thus, eighty-five inter simple sequence repeat (ISSR) primers were applied to detect polymorphisms among six major Korean ginseng cultivars and two foreign ginsengs. A total of 197 polymorphic bands with an average 5.8 polymorphic bands and 2.9 banding patterns per assay unit across six Korean ginseng cultivars and foreign ginsengs from 236 amplified ISSR loci with an average 6.9 loci per assay unit were generated by 34 out of 85 ISSR primers. Three species of Panax ginseng including the Korean ginseng cultivars, P. quinquefolius, and P. notoginseng, could be readily discriminated using most tested primers. UBC-821, UBC-868, and UBC-878 generated polymorphic bands among the six Korean ginseng cultivars, and could distinguish them from foreign ginsengs. Sequence characterized amplified region (SCAR) marker system was introduced in order to increase the reproducibility of the polymorphism. One SCAR marker, PgI821C650, was successfully converted from the randomly amplified polymorphism by UBC-821. It showed the expected dominant polymorphism among ginseng samples. In addition, the specific polymorphism for Sunwon was generated by treating Taq I restriction enzyme to polymerase chain reaction products of PgI821C650. These results will serve as useful DNA markers for identification of Korean ginseng, especially Sunwon cultivar, seed management, and molecular breeding program supplemented with marker-assisted selection.

• Journal of Ginseng Research
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• v.41 no.4
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• pp.469-476
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• 2017

Background: Panax ginseng Meyer (Asian ginseng) has a large nuclear genome size of > 3.5 Gbp in haploid genome equivalent of 24 chromosomes. Tandem repeats (TRs) occupy significant portions of the genome in many plants and are often found in specific genomic loci, making them a valuable molecular cytogenetic tool in discriminating chromosomes. In an effort to understand the P. ginseng genome structure, we characterized an ultrahigh copy 167-bp TR (Pg167TR) and explored its chromosomal distribution as well as its utility for chromosome identification. Methods: Polymerase chain reaction amplicons of Pg167TR were labeled, along with 5S and 45S rDNA amplicons, using a direct nick-translation method. Direct fluorescence in situ hybridization (FISH) was used to analyze the chromosomal distribution of Pg167TR. Results: Recently, we reported a method of karyotyping the 24 chromosome pairs of P. ginseng using rDNA and DAPI (4',6-diamidino-2-phenylindole) bands. Here, a unique distribution of Pg167TR in all 24 P. ginseng chromosomes was observed, allowing easy identification of individual homologous chromosomes. Additionally, direct labeling of 5S and 45S rDNA probes allowed the identification of two additional 5S rDNA loci not previously reported, enabling the refinement of the P. ginseng karyotype. Conclusion: Identification of individual P. ginseng chromosomes was achieved using Pg167TR-FISH. Chromosome identification is important in understanding the P. ginseng genome structure, and our method will be useful for future integration of genetic linkage maps and genome scaffold anchoring. Additionally, it is a good tool for comparative studies with related species in efforts to understand the evolution of P. ginseng.

• Journal of Life Science
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• v.17 no.10
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• pp.1441-1446
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• 2007

This study was conducted to establish the individual identification system and to estimate the genetic characteristic of Jeju native horse (JNH) using 13 microsatellite markers located on different horse autosomes. The markers were genotyped on 191 animals from five horse breeds including Jeju native horse (JNH). In total, 138 alleles were detected from the genotypes of 13 microsatellite markers. The average heterozygosities ranged from 0.317 to 0.902 and the polymorphic information content (PIC) ranged from 0.498 to 0.799 in JNH. We found that there were significant differences in allele frequencies in JNH when compared with other horse breeds. In ATH4 marker, there were specific allele frequence pattern that some of allele only found in JNH, Mongolian horse (MONG) and Jeju racing horse (JRH). The calculated cumulative power of discrimination (CPD) was 99.9% when nine microsatellite loci were used for analysis in the individual identification system. Also, the matching probability that two unrelated animals would show the same genotypes, was estimated to be $0.60{\times}10^{-10}$. Therefore, in the nine markers used in this study can be used for individual identification in the Jeju native horse population.