• Proceedings of the KIEE Conference
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• 2003.07d
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• pp.2552-2554
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• 2003

난수발생기 (Random generator-RG)와 GRNN을 이용한 분류기 설계방식을 제안하며, 이를 프로모터 염기서열의 분류에 적용한다. 주어진 난수범위에서 다중 분류기를 발생하였으며, 그 성능을 예측정확도와 분류민감도 측면에서 평가하였고, 분류민감도는 다시 전체와 개별적 프로모터에 대해서 세분화하여 평가하였다. 최적화된 분류기 상호간의 비교에서 제안된 기법은 모든 임계점에 대해서, 전체 분류민감도와 전체 예측정확도를 향상시키었으며, 이는 전체 분류 민감도에서 더 두드러졌다. 한편, 개별적 프로모터에 대한 분류민감도와 예측정확도도 평균적으로 향상되었다. 이 같은 결과로 제안된 기법이 분류와 예측성능을 동시에 증진하는데 매우 효과적임을 알 수 있었다.

• Korean Journal of Plant Taxonomy
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• v.37 no.2
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• pp.115-129
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• 2007

Using internal transcribed spacer (ITS) sequences and inter-simple sequence repeats (ISSRs) data, genetic diversity of a rare species, Hibiscus hamabo Siebold & Zucc. was examined for 3 populations in Jeju Island, Korea. A total of 14 nucleotide (excluding 3 ambiguous nucleotide) site variation in the ITS was observed from 18 individuals (Population 1, Hadori), which differed up to 13 bp in pair-wise comparison. On the contrary, the ITS sequences of all individuals in Populations 2 and 3 were identical. Genetic diversity estimates including Nei's gene diversity (h) generated by ISSR data were substantially high in Population 1 compared to other two populations. Low genetic variation in Populations 1 and 2 is considered due to genetic drift (bottleneck effect) and limited gene flow in these populations. Considering the differences in genetic diversity, protection of the Population 1(Hadori) is very critical for in situ conservation of Hibiscus hamabo in Korea. If ex situ conservation is required, making the full use of Population 1 will be most efficient.

• Journal of Mushroom
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• v.9 no.1
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• pp.27-33
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• 2011

This study was carried to identify a correct species and asses genetic diversity within the same species of Trametes spp. preserved in Division of applied Microbiology The morphological and cultural characteristics of preserved strains were observed through microscope and investigated on PDA, respectively. Contaminated isolates showed different growth rates, morphology and color of hyphae. We have reconstructed the phylogenetic tree of a select group of Trametes spp. using nucleotide sequences of the internal transcribed spacer region(ITS) region. The phylogenetic tree was constructed by using the neighbor-joining method. PELF primers of 20-mer were used to assess genetic diversity of preserved isolates. Sequence analysis showed that five strains were different species and six strains were identified completely different nomenclature. According to the analysis of ITS sequences, the genus Trametes clustered into four distinct group, most of which correlated with species-groups identified by RAPD method. Seven isolates included TM 01 strain showed high similarity with Trametes versicolr, TM 07 and TM 10 high similarity with Trametes gibbosa, and TM 05 high similarity with Trametes elegans. But isolates collected in the United States was identified as T. junipericola. T. gibbosa and T. versicolor by RAPD analysis of genetic polymorphisms showed a very different band patterns and these strains showed different band patterns on areas. As the result of RAPD and ITS region sequences analysis for preserved isolates, it seems likely that 11 isolates of Trametes spp. may be need to reclassify or eliminate from preserved catalogue.

• Korean Journal of Plant Taxonomy
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• v.38 no.4
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• pp.345-358
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• 2008

The systematic position of Cymopterus melanotiligia (H. Boissieu) C. Y. Yoon in Apiaceae was revaluated based on the ITS sequence data. Its diagnostic characteristics include its asymmerty mericarps, 3-4 mericarp ribs, winged dorsal ribs, and ternate leaves. It is morphologically similar to Tilingia tsusimensis and Pimpinella having ternate leaves. It is distinguished from Ostericum having symmerty mericarps, 5 mericarp ribs, and rounded dorsal ribs. Also it looks like Angelica with broadly winged lateral ribs and strongly dorsally compressed mericarps, but is distinguished by having its conspicuous calyx teeth and unilayer pericarps. Cymopterus melanotiligia formed a different clade group with Cymopterus species distributed in North America based on ITS sequences, and it supports the close relationships with Halosciastrum melanotilingia. Thus, we conclude that this species is here referred to Halosciastrum melanotilingia (H. Boissieu) Pimenov & Tikhomirov.

• The Korean Journal of Mycology
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• v.27 no.6 s.93
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• pp.406-411
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• 1999

The phylogenetic relationships of black-spored basidioid taxa (mainly coprinoid taxa) and an agaric-like gastroid taxon were studied. The sequences of internal transcribed spacer regions (ITS) partially including 17S, 25S and 5.8S from 14 species (Coprinus comatus, C. atramentarius, C. micaceus, C. cinereus, C. disseminatus, C. rhizophorus, C. radians, C. echinosporus, Psathyrella candolleana, Podaxis pistillaris, Conocybe lactea, Bolbitius demangei, Agaricus balzei, and Stropharia rugosoannulata) were compared. The reciprocal homologies of ITS sequences among these species were in the range of $38.7{\sim}77.2%$. Black-spored taxa were classified into four clusters. Cluster I comprised C. micaceus, C. radians, and C. disseminata. Cluster II is consisted of C. cinereus, C. echinosporus, C. rhizophorus, and C. atramentarius. On the other hand, C. comatus is in cluster III with Agaricus balzei and Podaxis pistillaris even though this species is belonging to the section Coprinus in morphological aspect. Psathyrelloid taxon is included in cluster II. The question of the origin of secotioid (agaric-like) fungi has been taken, though largely on theoritical suggestions as to whether gastroid taxa give rise to agarics with secotioid taxa as intermediates or whether secotioid taxa are evolutionary novelities arising from many distinct groups of agarics. In this relationship, it was shown that secotioid taxon evolved from within agaric species.

• Korean Journal of Plant Taxonomy
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• v.34 no.4
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• pp.335-358
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• 2004

To investigate molecular phylogenetic relationships and to test hypothesis of hybrid origin of Ranunculus cantoniensis (Ranunculaceae), the sequences of nrDNA and chloroplast DNA were analyzed for 8 taxa and 25 accessions including 5 accessions of outgroup. In the phylogenetic trees by analyses of maximum parsimony and maximum likelihood for ITS nrDNA sequences and combined data of psbA-trnH, rps16 and trnL sequences of cpDNA, R. cantoniensis was most closely related to R. chinensis, and then to R. taciroi and R. silerifolius. The molecular phylogenetic relationships were not congruent with the previous report that R. cantoniensis was most closely related to R. silerifolius. In the sequence analysis of ITS and psbA-trnH, rps16, trnL for R. cantoniensis and the related taxa, R. cantoniensis showed polymorphism. It supported that the polymorphism also was reported in chromosome number and karyotype of R. cantoniensis. Ranunculus cantoniensis shared the marker gene of R. chinensis and R. silerifolius in ITS, and one of R. silerifolius in cpDNA. These results supported the hypothesis that R. cantoniensis was caused by hybridization between R. chinensis and R. silerifolius based on chromosome number and karyotype, and also estimated that R. silerifolius might be of maternal origin and R. chinensis be paternal.

• Journal of Life Science
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• v.27 no.3
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• pp.351-354
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• 2017

Cowpea (Vigna unguiculata (L.) Walp.) is recognized as a potential source of protein and other nutrients. The genus Vigna includes 100 wild species of plants. Especially, Vigna unguiculata includes annual cowpeas (ssp. unguiculata) and ten wild perennial subspecies. DNA sequence of internal transcribed spacer (ITS) region was determined for Vigna sinensis, one of native plant, which was found in recent but thought to have gone extinct in Korea. The seeds of Vigna sinensis used in this study were donated from Dong-Young Jo. The DNA sequence of ITS-5.8S-ITS2 for Vigna sinensis obtained from this study was deposited as Vigna sinensis AY195581 on GenBank of NCBI (National Center for Biotechnology Information). We investigated the sequence-based phylogenetic relationships of plants related and clarified its taxonomical position. DNA similarities among subspecies including Vigna unguiculata showed the range 98 to 100% in sequence-based phylogenetic analysis using total 507 base pairs of ITS1, 5.8S and ITS2. Vigna unguiculata and subspecies were grouped independently as one cluster from other Vigna species used in the phylogenetic analysis. In this study, based on the phylogenetic analysis using the ITS1-5.8S-ITS2 sequence of Vigna sinensis, it may be concluded to be classified to one of Vigna unguiculata substrains.

• The Korean Journal of Malacology
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• v.20 no.2
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• pp.171-181
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• 2004

Partial sequences of the mitochondrial cytochrome oxidase subunit Ⅰ(mtCOI) gene of veneroid clams were obtained to eluciadate molecular phylogeny. A total of nine veneroids and one corbiculid were collected from southern and western sea of Korea. The mtCOI sequences of the clams obtained from the present study and three veneroids sequences from GenBank were analyzed by maximum parsimony and neighbor-joining methods. The subfamilies Samarangiinae, Dorsiniinae, Cyclinae, Meretricinae and Chioninae were monophyletic, but Pitarinae was paraphyletic. One transitions and two transversions among two samples of Ruditapes philippinarum and a R. variegata were observed.

• Journal of Aquaculture
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• v.21 no.3
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• pp.139-145
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• 2008

Morphological classification of echinoid species has many difficulties because of their phenotypic variations. In the present study, we analyzed morphotypes and partial mitochondrial 12S rDNA sequences of four sea urchin species classified as Pseudocentrotus depressus, Anthocidaris crassispina, Hemicentrotus pulcherrimus and Strongylocentrotus nudus, and unidentified four species collected from the coasts of the East sea. Their genomic DNAs were extracted from gonads and mitochondrial 12S rDNA sequences were amplified by the polymerase chain reaction (PCR) method. The sequence identities among the known four sea urchin species were 87.4-95.6%. The sequence identities among the unidentified four species were 99.4-99.6% and showed the highest homology to S. intermedius(99.8%). Thus, our phylogenetic tree indicates that the unidentified four species belong to S. intermedius.

• KSBB Journal
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• v.18 no.1
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• pp.39-44
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• 2003

A Gene content phylogenetic tree and a 16s rRNA based phylogenetic tree were compared for 33 whole-genome sequenced procaryotes, neighbor joining and bootstrap methods (n=1,000). Ratio of conserved COG (clusters of orthologous groups of proteins) to orthologs revealed that they were within the range of 4.60% (Mezorhizobium loti) or 56.57% (Mycopiasma genitalium). This meant that the ratio was diverse among analyzed procaryotes and indicated the possibility of searching for useful genes. Over 20% of orthologs were independent among the same species. The gene content tree and the 16s rDNA tree showed coincidence and discordance in Archaeabacteria, Proteobacteria and Firmicutes. This might have resulted from non-conservative genes in the gene content phylogenetic tree and horizontal gene transfer. The COG based gene content tree could be regarded as a midway phylogeny based on biochemical tests and nucleotide sequences.