• The Korean Journal of Mycology
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• v.27 no.4 s.91
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• pp.274-279
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• 1999

The internal transcribed spacer regions(ITS) of the ribosomal DNA gene repeat from Coprinus and Psathyrella spp. were amplified using polymerase chain reaction (PCR) and sequenced. Sequences from 11 species including Coprinus comatus, C. atramentarius, C. micaceus, C. cinereus, C. rhizophorus, C. radians, C. echinosporus, C. disseminatus, Psathyrella candolleana, P. spadiceogrisea and Stropharia rugosoannulata were compared. The spacer region I and II were $258{\sim}301\;bp\;and\;253{\sim}275\;bp$ in length respectively and partially contained 17S, 5.8S and 25S. The reciprocal homologies of ITS sequences among these strains were in the range of $43.9{\sim}96.0%$. According to the analysis of ITS sequences, Coprinus and Psathyrella spp. were classified into three clusters. Cluster I consisted of Coprinus lagopus, C. cinereus, C. echinosporus, C. rhizophorus, and C. atramentarius. Cluster II comprised C. micaceus, C. radians, C. disseminatus, Psathyrella candolleana, and P. spadiceogrisea. On the other hand C. comatus is in Cluster III with Stropharia rugosoannulata even though this species is belonging to the section Coprinus in morphological aspect. These results suggest that taxonomic position of Psathyrella would better be inculded in genus Coprinus. Coprinus comatus, the type species of Coprinus, gives a doubt on monophyletic evolution and is assumed to be paraphyletic or polyphyletic.

• Journal of Microbiology
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• v.38 no.1
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• pp.44-47
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• 2000

The cDNA of VP2/NS junction region on segment A of the marine birnavirus (MBV) isolated from flounder (DS strain) was amplified using the reverse transcription (RT)-polymerase chain reaction (PCR). Its cDNA nucleotide and deduced amino acid sequences were analyzed, and compared with the reference strains of MBV and infectious pancreatic necrosis virus (IPNV). Analyses of the nucleotide and deduced amino acid sequences revealed that the DS strain is very similar to the reference strains of MBV, distant from the IPNV.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2000.11a
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• pp.69-70
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• 2000

The completion of sequencing human genome would motivate us to map millions of human cDNAs onto the unique ruler "genome sequence", in order to identify the exact address of each cDNA together with its exons, its promoter region, and its alternative splicing patterns. The expression patterns of some cDNAs could therefore be associated with these precise gene addresses, which further accelerate studies on mining correlations between motifs of promoters and expressions of genes in tissues. Towards the realization of this goal, we have developed a time-and-space efficient software named SQUALL that is able to map one cDNA sequence of length a few thousand onto a long genome sequence of length thirty million in a couple of minutes on average. Using SQUALL, we have mapped twenty thousand of our Bodymap (http://bodymap.ims.u-tokyo.ac.jp) cDNAs onto the genome sequences of Chr.21st and 22nd. In this talk, I will report the status of this ongoing project.

• Korean Journal of Plant Resources
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• v.27 no.3
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• pp.249-255
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• 2014

The rice belonging to Oryza sativa is not only has significant economic importance, for it is the major source of nutrition for about 3 billion all around the world. But also plays a vital role as a model organism, because it has a number of advantages to be a model plant, such as efficient transformation system and small genome size. Many methods and techniques have been conducted to attempt to distinguish different Oryza sativa species, such as amplified fragment length polymorphism (AFLP), random amplified polymorphic DNA (RAPD), simple sequence repeat (SSR) and so on. However, studies using sequence analysis of internal transcribed spacer (ITS), a region of ribosomal RNA has not been reported until now. This study was undertaken with an aim to understand the phylogenetic relationships among sixteen isolates of Oryza sativa collected from abroad and fifteen isolates collected from Korea, using ribosomal RNA (rRNA) internal transcribed spacer (ITS) sequences to compare the phylogeny relationships among different Oryza sativa species. The size variation obtained among sequenced nuclear ribosomal DNA (nrDNA) ITS region ranged from 515bp to 1000bp. The highest interspecific genetic distance (GD) was found between Sfejare 45 (FR12) and Anapuruna (FR15). Taebong isolate showed the least dissimilarity of the ITS region sequence with other thirty isolates. This consequence will help us further understanding molecular diversification in intra-species population and their phylogenetic analysis.

• The Korea Journal of Herbology
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• v.25 no.4
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• pp.47-54
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• 2010

Objectives : The original plant species of Schisandrae Fructus (O-mi-ja) is prescribed as Schisandra chinensis $B_{AILL.}$, in Korea, but S. chinensis $B_{AILL.}$ and S. sphenanthera $R_{EHD.}$ et $W_{ILS.}$ in China. Moreover, fruit of several other species in genus Schisandra also have been used as the same herbal medicines. To develop a reliable method for correct identification of Schisandrae Fructus and to evaluate the phylogenetic relationship of S. chinensis and its related species, we analyzed internal transcribed spacer (ITS) sequences of nuclear ribosomal DNA (nrDNA). Methods : Twenty-four plant samples of three Schisandra species and one Kadsura species, S. chinensis $B_{AILL.}$, S. spenanthera $R_{EHD.}$ et $W_{ILS.}$, S. nigra $M_{ax.}$ and Kadsura japonica $D_{UNAL}$ were collected from each different native habitate and farm in Korea and China. The nrDNA-ITS region of each samples were amplified using ITS1 and ITS4 primer and nucleotide sequences were determined after sub-cloning into the pGEM-Teasy vector. Authentic marker nucleotides were estimated by the analysis of ClastalW based on the entire nrDNA-ITS sequence. Results : In comparative analysis of the nrDNA-ITS sequences, we found specific nucleotide sequences including indels (insertions and deletions) and substitutions to distinguish C. chinensis, S. spenanthera, S. nigra, and K. japonica. These sequence differences at corresponding positions are avaliable nucleotide markers to determine the botanical origin of O-mi-ja. Moreover, we evaluated the phylogenetic relationship of four plant species by the analysis of nrDNA-ITS sequences. Conclusions : These marker nucleotides would be useful to identify the official herbal medicines by the providing of definitive information that can identify each plant species and distinguish it from unauthentic adulterants for O-mi-ja.

• Journal of Mushroom
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• v.7 no.3
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• pp.98-104
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• 2009

Phylogenetic relationships of Hypsizygus mamoreus and Lyophyllum decastes artificial cultivated using ITS sequences and RAPD polymorphism have been analyzed. Based on ITS region sequences of 14 strains, we could divide into 2 group as group1 to Hypsizygus mamoreus and the control isolated group2 to Lyophyllum decastes were identified as the same species. Restrict analysis of rDNA ITS region which was amplified by PCR, 14 collected strains could be classified into 4 clusters. There was approximately 58% genetic similarity between cluster I(SPA 100, 101, 102) and cluster II(SPA 200, 208 and SPA 201, 202), 41% between cluster III(SPA 104, 103, 203) and cluster IV(SPA 204, 206, 207, 205) by BLAST analysis. RAPD polymorphisms were used to analyze the species diversity of artificially cultivated Lyophyllum decastes SPA 202. As a result, similarity between SPA 202 and SPA 203 was 75%, at the same time, similarity between SPA 202 and Pleurotus eryngii SPA 103 and SPA 104 was 65%.

• ALGAE
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• v.28 no.4
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• pp.307-330
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• 2013

The genus Cryptomonas is easily recognized by having two flagella, green brownish color, and a swaying behavior. They have relatively simple morphology, and limited diagnostic characters, which present a major difficulty in differentiating between species of the genus. To understand species delineation and phylogenetic relationships among Cryptomonas species, the nuclear-encoded internal transcribed spacer 2 (ITS2), partial large subunit (LSU) and small subunit ribosomal DNA (rDNA), and chloroplast-encoded psbA and LSU rDNA sequences were determined and used for phylogenetic analyses, using Bayesian and maximum likelihood methods. In addition, nuclear-encoded ITS2 sequences were predicted to secondary structures, and were used to determine nine species and four unidentified species from 47 strains. Sequences of helix I, II, and IIIb in ITS2 secondary structure were very useful for the identification of Cryptomonas species. However, the helix IV was the most variable region across species in alignment. The phylogenetic tree showed that fourteen species were monophyletic. However, some strains of C. obovata had chloroplasts with pyrenoid while others were without pyrenoid, which used as a key character in few species. Therefore, classification systems depending solely on morphological characters are inadequate, and require the use of molecular data.

• Korean Journal of Plant Taxonomy
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• v.47 no.3
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• pp.180-188
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• 2017

We evaluated the actual distribution, present status, and number of remnant individuals of Korean Sagittaria aginashi (Alismataceae) based on herbarium specimens and field surveys. We also reidentified Korean S. aginashi by analyzing sequences of the internal transcribed spacer (ITS) region. We found nine specimens of S. aginashi in herbaria from four localities housed at the Osaka Museum of Natural History (OSA) and at the Korea National Herbarium (KH). During our field research, we could not confirm the current statuses of two collection localities (Taereung and Ansan-si), though this was not the case for Ulsan-si. In addition, we found two new localities in Ulsan-si and Yangsan-si. These three remnant populations are distributed in wetlands in mountainous areas (elev. 480-740 m). With regard to the number of flowering and immature individuals in the three localities, there were <50 and <2,000, respectively, in total. ITS sequences demonstrated that the sequences of Korean and Japanese S. aginashi are uniform and distinct from other Sagittaria species. These results indicate that S. aginashi is a rare and threatened species in Korea. It should be listed as an endangered species on the Korean Red List and requires urgent protection by conservation programs, including the extensive surveys of other possible natural habitats.

• Ocean Science Journal
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• v.40 no.3
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• pp.155-166
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• 2005

New PCR primers (N=18) were designed for the isolation of complete SSU to LSU rDNA sequences from the dinoflagellate Alexandrium tamarense. Standard PCR, employing each primer set selected for amplifications of less than 1.5 kb, successfully amplified the expected rDNA regions of A. tamarense (Korean isolate, HY970328M). Complete SSU, LSU rDNAs and ITS sequences, including 5.8S rDNA, were recorded at 1,800 bp, 520 bp and 3,393 bp, respectively. The LSU rDNA sequence was the first report in Alexandrium genus. No intron was found in the LSU rRNA coding region. Twelve D-domains within the LSU rDNA were put together into 1,879 bp (44.4% G+C), and cores into 1514 bp (42.8% G+C). The core sequence was significantly different (0.0867 of genetic distance, 91% sequence similarity) in comparison with Prorocentrum micans (GenBank access. no. X16108). The D2 region was the longest in length (300 bp) and highly variable among the 12 D-domains. In a phylogenetic analysis using complete LSU rDNA sequences of a variety of phytoplankton, A. tamarense was clearly separated with high resolution against other species. The result suggests that the sequence may resolve the taxonomic ambiguities of Alexandrium genus, particularly of the tamarensis complex.

• International Journal of Industrial Entomology and Biomaterials
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• v.27 no.1
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• pp.142-158
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• 2013

The bumblebee, Bombus ignitus (Hymenoptera: Apidae), is a valuable natural resource that is widely utilized for greenhouse pollination in South Korea. Understanding the magnitude of genetic diversity and geographic relationships is of fundamental importance for long term preservation and utilization. As a first step, we sequenced a partial COI gene of mitochondrial DNA (mtDNA) corresponding to the "DNA barcode" region and the complete internal transcribed spacer 2 (ITS2) of nuclear ribosomal DNA from 88 individuals collected in nine South Korean localities. The complete ITS2 sequences were longest among known insects, ranging in size from 2,034 bp ~ 2,052 bp, harboring two duplicated 112-bp long repeats. The 658-bp long mtDNA sequences provided only six haplotypes with a maximum sequence divergence of 0.61% (4 bp), whereas the ITS sequences provided 84 sequence types with a maximum sequence divergence of 1.02% (21 sites). The combination of the current COI data with those of published data suggest that the B. ignitus in South Korea and China are genetically a large group, but those in Japan can be roughly separated into another group. Overall, a very high per generation migration ratio, a very low level of genetic fixation, and no discernable hierarchical population were found to exist among the South Korean populations of B. ignitus, which suggests panmixia. This finding is consistent with our understanding of the dispersal capability of the species.