• ALGAE
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• 제21권2호
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• pp.169-174
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• 2006

We have cultured more than 100 Arctic and Antarctic cryophilic microalgal strains in KOPRI culture collections of polar microorganisms (KCCPM). Among them, we tried to identify an Antarctic strain, KOPRI AnM0008 by morphological and molecular analysis. Nuclear SSU rDNA and plastid rbcL sequences were used to identify the strain. It was identified as Porosira pseudodenticulata based on SSU sequence data showing 99% identity with GenBank X85398. This result was supported by morphological features like solitary labiate process, external foramina and internal cribra by optical and scanning electron microscope. Morphological identification and molecular analysis on polar cryophilic microalgae will be accomplished to construct the databases for KCCPM.

• 대한임상검사과학회지
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• 제48권1호
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• pp.15-21
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• 2016

Aspergillus는 가장 흔하게 감염을 일으키는 기회 감염균이다. 검사실에서 Aspergillus의 동정은 대부분 형태학적으로 이루어진다. 최근에는 형태학적으로 동정이 안 되거나, 속 수준까지만 동정이 되는 까다로운 균들 동정하기 위하여 분자유전학적인 방법들이 제안되고 있다. 임상검체에서 분리한 475건의 Aspergillus는 Aspergillus fumigatus 257주(54.1%), A. niger 101주(21.3%), A. flavus 43주(9.1%), A. terreus 29주(6.1%), Aspergillus nidulans 2주(0.4%), 그리고 Aspergillus clavatus 1주(0.2%), 그리고 Aspergillus species는 42주(8.8%)이었다. 미동정 균주와 종 구분을 위한 11건의 염기서열분석에서는 Aspergillus fumigatus 5주, Aspergillus falvus 1주, Aspergillus terreus 1주, Aspergillus lentulus 1주 동정되었다. Aspergillus versicolor 2주, 그리고 1주는 Emericella parvathecia로 동정되었다. Aspergillus의 92.2%는 형태학적으로 동정이 가능하였고, 8.8%는 종 수준의 동정이 불가능하였다. 종 수준의 동정을 하기 위해서는 ITS와 D1D2를 이용한 염기서열분석이 유용한 것으로 사료된다.

• 한국작물학회지
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• 제49권5호
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• pp.429-433
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• 2004

A single recessive gene, rxp, controls the bacterial leaf pustule (BLP) resistance in soybean and in our previous article, it has been mapped on linkage group (LG) D2 of molecular genetic map of soybean. A total of 130 recombinant inbred lines (RILs) from a cross between BLP-resistant SS2-2 and BLP-susceptible Jangyeobkong were used to identify molecular markers linked to rxp. Fifteen simple sequence repeat (SSR) markers on LG D2 were screened to construct a genetic map of rxp locus. Only four SSR markers, Satt135, Satt372, Satt448, and Satt486, showed parental polymorphisms. Using these markers, genetic scaffold map was constructed covering 26.2cM. Based on the single analysis of variance, Satt372 among these four SSR markers was the most significantly associated with the resistance to BLP. To develop new amplified fragment length polymorphism (AFLP) marker linked to the resistance gene, bulked segregant analysis (BSA) was employed. Resistance and susceptible bulks were made by pooling equal amount of genomic DNAs from ten of each in the segregating population. A total of 192 primer combinations were used to identify specific bands to the resistance, selecting three putative AFLP markers. These AFLP markers produced the fragment present in SS2-2 and the resistant bulk, and not in Jangyeobkong and the susceptible bulk. Linkage analysis revealed that McctEact97 $(P=0.0004,\;R^2=14.67\%)$ was more significant than Satt372, previously reported as the most closely linked marker.

• The Plant Pathology Journal
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• 제16권1호
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• pp.29-35
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• 2000

The internal transcribed spacer regions (ITS I, 5.8S and ITS II) of the ribosomal DNAs were amplified from Korean isolates of Phytophthora spp. and sequenced to characterize them. Sequences from 33 isolates previously identified as P. boehmeriae, P. cactprum, P. cambivora, P. capsici, P. cinnamomi, P. erythroseptica, P. infestans, P. megasperma, P. melonis, P. nicotianae, P. palmivora and P. sojae were compared with published sequences, and a phylogenetic tree was produced. All isolates belonging to 10 species, P. cactorum, P. cambivora, P. capsici, P. cinnamomi P. citricola, P. infestans, P. nicotianae, P. palmivora and P. sojae were clearly clustered into published isolates of each species above 97% bootstrap value. Cucurbits isolates of Phytophthora previously identified as either P. melonis or P. drechsleri showed distinct evolutionary lineages from the P. megasperma was closely related to isolates of P. cryptogea-P. drechsleri showed distinct evolutionary lineages from the P. cryptogea-P. drechsleri complex group, indicating that P. melonis is a valid species. A Korean isolate of P. megasperma was closely related to isolates of P. erythroseptica showed distant genetic relationship with published isolates of P. erythroseptica (CBS 956.87). It is probable that the two Korean isolates could be genetically different from foreign isolates or misidentified. A grouping of species according to ITS sequence divergence matched, to some degree, the broad classification based on type of papilla. However, a separation of semi-papillate species and papillate species was not wvident in this study.

• International Journal of Industrial Entomology and Biomaterials
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• 제31권2호
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• pp.62-69
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• 2015

The Asian cavity-nesting honeybee, Apis cerana (Hymenoptera: Apidae), has been extensively studied for its biogeography and genetic diversity, but the molecules utilized in past studies were mainly ~90 bp long mitochondrial non-coding sequences, located between $tRNA^{Leu}$ and COII. Thus, additional molecular markers may enrich our understanding of the biogeography and genetic diversity of this valuable bee species. In this study, we reviewed the public genome database to find introns of cDNA sequences, with the assumption that these introns may have less evolutionary constraints. The six introns selected were subjected to preliminary tests. Thereafter, two introns, titled White gene and MRJP9 gene, were selected. Sequencing of 552 clones from 184 individual bees showed a total of 222 and 141 sequence types in the White gene and MRJP9 gene introns, respectively. The sequence divergence ranged from 0.6% to 7.9% and from 0.26% to 17.6% in the White gene and the MRJP9 introns, respectively, indicating higher sequence divergence in both introns. Analysis of population genetic diversity for 16 populations originating from Korea, China, Vietnam, and Thailand shows that nucleotide diversity (π) ranges from 0.003117 to 0.025837 and from 0.016541 to 0.052468 in the White gene and MRJP9 introns, respectively. The highest π was found in a Vietnamese population for both intron sequences, whereas the nine Korean populations showed moderate to low sequence divergence. Considering the variability and diversity, these intron sequences can be useful as non-mitochondrial DNA-based molecular markers for future studies of population genetics.

• 한국동물학회지
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• 제39권2호
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• pp.164-172
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• 1996

KP elements derived from Korean populations (Seoul, Cheonan and Taegu) of Drosophila melunoguster were examined for their molecular structure. The entire 1.15 kb sequence of the three KP elements KC-137 (Cheonan), KS-95 (Seoul) and KT-99 (Taegu) have been obtained by PCR amplification using inverted repeat primers and DNA sequencing. The 1.15 kb fragments of KP elements were cloned into pCRmll vector plasmids, and subsequently sequenced. The sequence of the three KP elements in these populations suggested that there might have been derived from the complete P element by a 1753 bp internal deletion between positions 808 and 2560. Therefore these KP elements were confirmed to be identical to that isolated from M'10 strains widely distributed in most Eurasian populations of D. melanoguster. Sequence comparison with the 2.9 kb complete P element in pn25.1 revealed that KC-137 has only shown to be two base substitutions of A to G and G to A at positions 62 and 242, respectively. The retained sequence of the two KP elements KS-95 and KT-99 shows complete homology to the P factor in pn25.1. Based on this result, the two base substitutions in KC-137 might be due to Taq DNA pollunerase errors. Finally, it is suggested that the high copy numbers of KP elements provieds an explanation for the suppression of P-mediated hybrid dvssenesis in Korean population of D. melunogoster.

• BMB Reports
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• 제53권5호
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• pp.260-265
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• 2020

Scorpion venom comprises a cocktail of toxins that have proven to be useful molecular tools for studying the pharmacological properties of membrane ion channels. HelaTx1, a short peptide neurotoxin isolated recently from the venom of the scorpion Heterometrus laoticus, is a 25 amino acid peptide with two disulfide bonds that shares low sequence homology with other scorpion toxins. HelaTx1 effectively decreases the amplitude of the K⁺ currents of voltage-gated Kv1.1 and Kv1.6 channels expressed in Xenopus oocytes, and was identified as the first toxin member of the κ-KTx5 subfamily, based on a sequence comparison and phylogenetic analysis. In the present study, we report the NMR solution structure of HelaTx1, and the major interaction points for its binding to voltage-gated Kv1.1 channels. The NMR results indicate that HelaTx1 adopts a helix-loop-helix fold linked by two disulfide bonds without any β-sheets, resembling the molecular folding of other cysteine-stabilized helix-loop-helix (Cs α/α) scorpion toxins such as κ-hefutoxin, HeTx, and OmTx, as well as conotoxin pl14a. A series of alanine-scanning analogs revealed a broad surface on the toxin molecule largely comprising positively-charged residues that is crucial for interaction with voltage-gated Kv1.1 channels. Interestingly, the functional dyad, a key molecular determinant for activity against voltage-gated potassium channels in other toxins, is not present in HelaTx1.

• Plant Breeding and Biotechnology
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• 제2권3호
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• pp.224-230
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• 2014

Amplified fragment length polymorphism (AFLP) is a molecular marker technique based on DNA and is extremely useful in detection of high polymorphism between closely related genotypes like Korean wheat cultivars. Six sequence characterized amplified regions (SCARs) have been developed from inter simple sequence repeat (ISSR) analysis which enabled the identification and differentiation of 13 Korean wheat cultivars from the other cultivars. We used six combinations of primer sets in our AFLP analysis for developing additional cultivar-specific markers in Korean wheat. Fifty-eight of the AFLP bands were isolated from EA-ACG/MA-CAC, EA-AGC/MA-CTG and EA-AGG/MA-CTA primer combinations. Of which 40 bands were selected to design SCAR primer pairs for Korean wheat cultivar identification. Three of 58 amplified primer pairs, KWSM006, KWSM007 and JkSP, enabled wheat cultivar identification. Consequently, 23 of 32 Korean wheat cultivars were classified by eight SCAR marker sets.

• Animal Systematics, Evolution and Diversity
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• 제34권3호
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• pp.162-167
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• 2018

To confirm the genetic identification and phylogenetic relationships of unidentified 6 baleen whales by-caught from 2002 to 2016, a partial sequence of approximately 500 base pair (bp) of the mitochondrial DNA (mtDNA) control region was analyzed and compared to published sequence from Genbank. Our results indicated that the two individuals among 6 specimens are clustered with Omura's whale clade through phylogenetic analysis, which had only a single haplotype. Omura's whale was reclassified as a new species in 2003 and they had not been previously reported in Korean waters. This study firstly revealed existence of Omura's whale in Korean waters by molecular analysis based on mtDNA control region.

• Fisheries and Aquatic Sciences
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• 제13권4호
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• pp.272-277
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• 2010

Seagrasses are marine angiosperms of ecological importance in providing shelter and food to aquatic species as well as maintaining the carbon cycle on earth. Phyllospadix iwatensis is a seagrass of the family Zosteraceae and is distributed along the eastern coast of Korea. The nucleotide sequences of P. iwatensis nuclear genes encoding 18S ribosomal RNA (rRNA) and internal transcribed spacer-1 (ITS-1) were determined for molecular phylogenetic analysis. Genomic DNA was isolated from P. iwatensis and used for PCR amplification of 18S rRNA and ITS-1. Examination of the 18S rRNA sequence of P. iwatensis showed a close (99% similarity) relationship to Zostera noltii, another genus of Zosteraceae, but a distant (84% similarity) evolutionary relationship to other macroalgal Laminariales species. Further discrepancies found in ITS-1 nucleotide sequences between closely related species indicate that the sequence information could be used for species identification.