• Korean Journal of Medicinal Crop Science
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• v.13 no.2
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• pp.115-120
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• 2005

Broadening the genetic base of Platycodon grandiflorum DC. cultivar to sustain improvement requires assessment of genetic diversity available in P. grandiflorum DC.. The objective of this study was to analyze the genetic variation, genetic relationship among 48 samples collected from East-Asian Area by means of RAPD-PCR (random amplified polymorphic DNA-polymerase chain reaction) markers. From the 18 primers tested, produced total 211 bands with an average of 11.7 bands per primer and obtained 103 polymorphic band with an average of 5.7 bands per primer,s revealed relatively high percentage of polymorphic bands (48.8%). The genetic similarities calculated from RAPD data varied from 0.688 to 0.994 and were clustered to six major groups on a criterion of 0.78 similarity coefficient. The present study has revealed the significant genetic similarity among the samples tested. The analysis of genetic relationships in P. grandiflorum using RAPD-PCR banding data can be useful for the breed improvement.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.12
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• pp.1696-1700
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• 2005

Five China native cattle breeds have been characterized by using 10 microsatellite DNA markers. The studied populations can be divided into five groups: Luxi cattle, Nanyang cattle, Jinnan cattle, Qinchuan cattle and Yanbian cattle. Allele frequencies were calculated and used for the characterization of the breeds and the study of their genetic relationships. Heterozygosity, polymorphism information content, the effective number of alleles was calculated. Nei' standard genetic distance (1978) was calculated and used for a neighbor-joining tree construction. NJ tree showed that Luxi cattle, Nanyang cattle, Jinnan cattle and Qinchuan cattle are closely related, whereas Yanbian cattle are clearly distinct from other four populations. The genetic relationship of five breeds corresponds to their history and geographic origins. This work analyzes the recent origin of these populations and contributes to the knowledge and genetic characterization of China native breeds.

• Mycobiology
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• v.43 no.4
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• pp.444-449
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• 2015

Arbuscular mycorrhizal fungi (AMF) are ubiquitous in the rhizosphere and form symbiotic relationships with most terrestrial plant roots. In this study, four strains of Rhizophagus clarus were cultured and variations in their growth characteristics owing to functional diversity and resultant effects on host plant were investigated. Growth characteristics of the studied R. clarus strains varied significantly, suggesting that AMF retain high genetic variability at the intraspecies level despite asexual lineage. Furthermore, host plant growth response to the R. clarus strains showed that genetic variability in AMF could cause significant differences in the growth of the host plant, which prefers particular genetic types of fungal strains. These results suggest that the intraspecific genetic diversity of AMF could be result of similar selective pressure and may be expressed at a functional level.

• ALGAE
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• v.33 no.3
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• pp.205-214
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• 2018

Red algae in the genus Portieria produce secondary halogenated monoterpenes, which are effective deterrents against herbivores, as secondary metabolites. Portieria hornemannii samples from various sites contain different concentrations of these metabolites, suggesting the existence of genetic diversity and cryptic species. To evaluate the genetic diversity and species distribution of Portieria in the northwest Pacific, we analyzed rbcL sequences of samples collected from Korea, Japan, and Taiwan. The phylogenetic analysis revealed five distinct lineages at the species level. One was recognized as Portieria japonica and the others were cryptic lineages in P. hornemannii. The rbcL haplotypes of P. japonica were genetically fragmented into two subgroups of geographic origin; Korean and Japanese. The four cryptic lineages within P. hornemannii were also geographically structured at a much finer scale. These results suggest that different genetic lineages in Portieria evolved from variable microhabitats, consequently influencing secondary metabolites. Further study is required to resolve the relationships between genetic and secondary metabolite variations in Portieria.

• Horticulture, Environment, and Biotechnology : HEB
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• v.59 no.6
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• pp.889-897
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• 2018

Currently, there is a lack of genetic markers capable of effectively detecting polymorphisms in Clematis. Therefore, we developed new markers to investigate inter- and intraspecific diversity in Clematis. Based on the complete chloroplast genome of Clematis terniflora, simple sequence repeats were explored and primer pairs were designed for all ten adequate repeat regions (cpSSRs), which were tested in 43 individuals of 11 Clematis species. In addition, the nuclear ITS region was sequenced in 11 Clematis species. Seven cpSSR loci were found to be polymorphic in the genus and serve as markers that can distinguish different species and be used in different genetic analyses, including cultivar identification to assist the breeding of new ornamental cultivars.

• Animal cells and systems
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• v.3 no.3
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• pp.285-293
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• 1999

Allele frequencies in twenty-two populations from nine Korean muricid species of five genera (Rapaninae and Ocenebrinae) wire analyzed genetically using 13 loci from 11 allozyme systems. The clustering patterns of these species were basically consistent with traditional groupings to two subfamilial categories based on shell and radula morphologies. Within six ocenebrine species it was apparent that Ceratostoma inornata and Pteropurpura adunca were most closely related to each other than to any other species belonging to the genus Ceratostoma. These results, along with other anatomical features 〔morphologies of albumin gland (female), egg capsule〕, suggest that the generic position of C. inornata, previously classified to be congeneric with other western Pacific Ceratostoma species, should be reconsidered. Our results show the close relationship of Nucella freycineti with other ocenebrine species, rather than with rapanines, which supports a previous suggestion that the genus Nucella should be placed with the subfamily Ocenebrinae rather than the subfamily Rapaninae.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2005.09a
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• pp.197-201
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• 2005

When we want to find out the regulatory relationships between genes from gene expression data, dimensionality is one of the big problem. In general, the size of search space in modeling the regulatory relationships grows in O(n$^2$) while the number of genes is increasing. However, hopefully it can be reduced to O(kn) with selected k by applying divide and conquer heuristics which depend on some assumptions about genetic network. In this paper, we approach the modeling problem in divide-and-conquer manner. We applied clustering to make the problem into small sub-problems, then hierarchical model process is applied to those small sub-problems.

• Genomics & Informatics
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• v.16 no.4
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• pp.33.1-33.9
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• 2018

Recently, there have been many studies in medicine related to genetic analysis. Many genetic studies have been performed to find genes associated with complex diseases. To find out how genes are related to disease, we need to understand not only the simple relationship of genotypes but also the way they are related to phenotype. Multi-block data, which is a summation form of variable sets, is used for enhancing the analysis of the relationships of different blocks. By identifying relationships through a multi-block data form, we can understand the association between the blocks in comprehending the correlation between them. Several statistical analysis methods have been developed to understand the relationship between multi-block data. In this paper, we will use generalized canonical correlation methodology to analyze multi-block data from the Korean Association Resource project, which has a combination of single nucleotide polymorphism blocks, phenotype blocks, and disease blocks.

• Korean Journal of Environmental Biology
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• v.26 no.4
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• pp.377-384
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• 2008

A cell is the product of a long period of evolution and can be represented as an optimized system (homeostasis). Stimuli from the outside environment are received by sensory apparatus on the surface of the cell and transferred through complicated pathways and eventually regulate gene expression. These signals affect cell physiology, growth, and development, and the interaction among genes in the signal transduction pathway is a critical part of the regulation. In this study, the interactions of deletion mutants and overexpression of the extracopies of the genes were used to understand their relationships to each other. Also, green fluorescent protein (GFP reporter gene) was fused to the regulatory genes to elucidate their interactions. Cooverexpression of the two genes in extracopy plasmids suggested that patS acts at the downstream of hetR in the regulatory network. The experiments using gfp fusion in different genetic background cells also indicated the epistasis relationships between the two genes. A model describing the regulatory network that controls cell development is presented.

• Korean Journal of Medicinal Crop Science
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• v.12 no.3
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• pp.214-218
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• 2004

Germplasms having valuable characters are increasjngly important for modern breeding programs. This study was conducted to obtain the basic data for effective use of genetic resources of Polygonatum. The relationship of seven Polygonatum species collected widely in Korea was analyzed by RAPD markers. Total number of alleles amplified by nineteen random primers were 114 to 157, and variation in number of alleles was also diverse among seven species examined. The seven species were divided into two groups; one was of Polygonatum stenophyllum and Polygonatum humile. the other was of Polygonatum inflatum, Polygonatum lasianthum, Polygonatum odoratum var. pluriflorum (1), (2), and for variegatum.