• 생명과학회지
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• 제14권6호
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• pp.963-966
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• 2004

능이버섯의 16S ribosomal DNA일부분, IT1, 5.85 ribosomal DNA, ITS2의 전부분, 28S ribosomal DNA 일부분이 포함된 ITS영역의 염기서열을 분석하였다. 이 부분은 716개의 염기쌍으로 구성되었다. 이를 Sarcadon속에 속하는 종들과 비교분석한 결과 같은 능이버섯의 ITS에 관한 다른 분석결과 염기치환 및 결실을 근거로 하였을 경우 $1.8\%$의 차이를 나타내었다. 또한 S. imbricatus와는 $1.8\%$, S. sequamous와는 $10\%$차이를 나타내었다. 이는 능이버섯이 숙주, 서식지 환경 등의 특수성 때문에 자연상태에서 유전자교류가 일어나지 않기 때문인 것으로 생각된다.

• ALGAE
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• 제24권3호
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• pp.129-138
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• 2009

DNA-based discrimination of species is a powerful way for morphologically otherwise similar species, like centric diatoms. Here, the author sequenced long-range nuclear ribosomal DNAs, spanning from the 18S to the D5 region of the 28S rDNA, of Stephanodiscus, particularly including a Korean isolate. By comparisons, high DNA similarities were detected from the rDNAs of nine Stephanodiscus (>99.4% in 18S rDNA, >98.0% in 28S rDNA). Their genetic distances, however, were significantly different (Kruskal-Wallis test, p < 0.01) compared to two related genera, namely Cyclotella and Discostella. In addition, genetic distances of 18S rDNAs were significantly different (Student’s t-test, p = 0.000) against those of the 28S rDNAs according to individual genera (Cyclotella, Discostella, and Stephanodiscus). Phylogenetic analyses showed that Stephanodiscus and Discostella showed a sister taxon relationship, and their clade was separated from a cluster of Cyclotella (1.00 PP, 100% BP). This suggests that Stephanodiscus has highly conserved sequences of both 18S and 28S rDNA; however, Stephanodiscus is well-separated from other freshwater centric diatoms, such as Cyclotella and Discostella, at the generic level.

• Parasites, Hosts and Diseases
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• 제45권3호
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• pp.181-190
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• 2007

The phylogenie relationships existing among 14 parasitic Platyhelminthes in the Republic of Korea were investigated via the use of the partial 28S ribosomal DNA (rDNA) D1 region and the partial mitochondrial cytochrome c oxidase subunit 1 (mCOI) DNA sequences. The nucleotide sequences were analyzed by length, G + C %, nucleotide differences and gaps in order to determine the analyzed phylogenie relationships. The phylogenie patterns of the 28S rDNA D1 and mCOI regions were closely related within the same class and order as analyzed by the PAUP 4.0 program, with the exception of a few species. These findings indicate that the 28S rDNA gene sequence is more highly conserved than are the mCOI gene sequences. The 28S rDNA gene may prove useful in studies of the systematics and population genetic structures of parasitic Platyhelminthes.

• Parasites, Hosts and Diseases
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• 제42권2호
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• pp.71-75
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• 2004

To determine the molecular phylogenie location of Plagiorchis muris, 28S D1 ribosomal DNA (rDNA) and mitochondrial cytochrome C oxidase subunit I (mtCOI) were sequenced and compared with other trematodes in the family Plagiorchiidae. The 28S D1 tree of P. muris was found to be closely related to those of P. elegans and other Plagiorchis species. And, the mtCOI tree also showed that P. muris is in a separate clade with genus Glypthelmins. These results support a phylogenie relationship between members of the Plagiorchiidae, as suggested by morphologic features.

• Animal cells and systems
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• 제6권2호
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• pp.145-151
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• 2002

Phylogenetic signal present in the mitochondrial 16S ribosomal RNA gene (16S rDNA) and the nuclear large subunit ribosomal RNA gene (28S rDNA) was explored to assess their utility in resolving family level relationships of the superfamily Tephritoidea. These two genes were chosen because they appear to evolve at different rates, and might contribute to resolve both shallow and deeper phylogenetic branches within a highly diversified group. For the 16S rDNA data set, the number of aligned sites was 1,258 bp, but 1,204 bp were used for analysis after excluding sites of ambiguous alignment. Among these 1,204 sites, 662 sites were variable and 450 sites were informative for parsimony analysis. For the 28S rDNA data set, the number of aligned sites was 1,102 bp, but 1,000 bp were used for analysis after excluding sites of ambiguous alignment. Among these 1000 sites, 235 sites were variable and 95 sites were informative for parsimony analysis. Our analyses suggest that: (1) while 16S rDNA is useful for resolving more recent phylogenetic divergences, 28S rDNA can be used to define much deeper phylogenetic branches; (2) the combined analysis of the 16S and 28S rDNAs enhances the overall resolution without losing phylogenetic signal from either single gene analysis; and (3) additional genes that evolve at intermediate rates between the 16S and 28S rDNAs are needed to further resolve relationships among the tephritoid families.

• Parasites, Hosts and Diseases
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• 제42권3호
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• pp.129-135
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• 2004

We compared the DNA sequences of the genus Metagonimus: M. yokogawai, M. takahashii, and M. miyatai. We obtained 288 D1 ribosomal DNA (rDNA) and mitochondrial cytochrome c oxidase subunit I (mtCOI) fragments from the adult worms by PCR, that were cloned and sequenced. Phylogenetic relationships inferred from the nucleotide sequences of the 28S D1 rDNA and mtCOI gene. M. takahashii and M. yokogawai are placed in the same clade supported by DNA sequence and phylogenie tree analysis in 28S D1 rDNA and mtCOI gene region. The above findings tell us that M. takahashii is closer to M. yokogawai than to M. miyatai genetically. This phylogenetic data also support the nomination of M. miyatai as a separate species.

• 생명과학회지
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• 제8권1호
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• pp.32-39
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• 1998

진딧물이 하나의 ribosomal RNA 유전자(rDNA)단위는 총 길이가 13,061bp이며 총 G/C비율은 59%이다. 그것을 구성하고 있는 각 영역의 길이와 G/C비율은 다음과 같다. 5’ETS는 G/C비율이 69%이고 843bp이다 . 18S rRNA 는 2,469bp이며 G/C비율은 59%이다. ITS I길이는 229bp이며 70%의 G/C비율이다. 5.8S rRNA는 160bp이며 63%의 G/C비율이다. ITS II는 325bp이며 70%dml G/C비율이다. 28S rRNA는 4, 147bp이고 60%의 G/C비율이다. IGS는 4,888bp로 55%의 G/C비율이다.

• ALGAE
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• 제25권2호
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• pp.65-70
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• 2010

The genus Chaetoceros provides highly diversified diatoms in marine systems. Morphological descriptions of the genus are well-documented, yet the DNA taxonomy of Chaetoceros has not been satisfactorily established. Here, the molecular divergences of the 18S-28S rDNA of Chaetoceros were assessed. DNA similarities were relatively low in both 18S (93.1 $\pm$ 3.9%) and 28S rDNA (81.0 $\pm$ 4.6%). Phylogenies of the 18S, 28S rDNAs showed that Chaetoceros was divided according to individual species, clustering the same species into single clades. Statistical analysis with corrected genetic (p-) distance scores showed that nucleotide divergence of Chaetoceros 28S rDNA significantly differed from that of 18S rDNA (Student's t-test, p < 0.05). This finding suggests that the 28S rDNA may be treated as a more suitable marker for species-level taxonomic distinctions of Chaetoceros.

• Parasites, Hosts and Diseases
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• 제45권4호
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• pp.301-306
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• 2007

We attempted to identify parasite DNA in the biliary stones of humans via PCR and DNA sequencing. Genomic DNA was isolated from each of 15 common bile duct (CBD) stones and 5 gallbladder (GB) stones. The patients who had the CBD stones suffered from cholangitis, and the patients with GB stones showed acute cholecystitis, respectively. The 28S and 18S rDNA genes were amplified successfully from 3 and/or 1 common bile duct stone samples, and then cloned and sequenced. The 28S and 18S rDNA sequences were highly conserved among isolates. Identity of the obtained 28S D1 rDNA with that of Clonorchis sinensis was higher than 97.6%, and identity of the 18S rDNA with that of other Ascarididae was 97.9%. Almost no intra-specific variations were detected in the 28S and 18S rDNA with the exception of a few nucleotide variations, i.e., substitution and deletion. These findings suggest that C. sinensis and Ascaris lumbricoides may be related with the biliary stoneformation and development.

• 한국응용곤충학회지
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• 제42권1호
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• pp.65-70
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• 2003

곤충자원의 대량사육을 위한 병 발생 예방과 해충의 효과적인 방제를 위하여 흰점박이꽃무지 이병충으로부터 곤충병원 사상균을 분리하였다. 전자현미경 관찰 결과 분리균주 KMA-1은 Metharizium속의 전형적인 쇠사슬형의 분생자를 paliside-like masse에 형성하였다. 따라서, 정확한 동정을 위하여 28S rRNA와 ITS염기 서열을 바탕으로 제작한 특이 프라이머쌍을 사용하여 PCR 반응을 수행하였다. 각각의 프라이머쌍을 사용한 PCR반응으로부터 특이 밴드가 검출되었으며 이 증폭 산물들의 염기 서열을 결정, 비교하였다. 분리 균주 KMA-1의 PCR산물인 28S rRNA와 ITS DNA염기서열을 GenBank데이터베이스에 등록된 염기서열 정보와의 상동성을 검색한 결과, 모두 Metarhizium anisopliae와 가장 높은 서열 상동성을 보였다. 이상의 결과로서 본 실험에서 분리 명명된 KMA-1는 M. anisopliae로 동정되었다.