• Korean journal of applied entomology
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• v.37 no.1
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• pp.23-30
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• 1998

Restriction fragment length polymorphism (RFLP) of a DNA has been a useful tool for analyzing genetic variation. This research was performed to establish an RFLP analytic method on the mitochondrial DNA (mtDNA) of the beet armyworm, Spodoptera exigua (Hiibner). To do this, total size of the mtDNA was measured and polymerase chain reaction (PCR) primers were selected. Its mitochondrial genome size was ca. 16kb. From a serial PCR test of 29 primers refered to the compilation of Simon et al. (1994), 22 primers were selected to amplify its mtDNA fragments. These primers resulted in short (300-700 bp) or long (1000-2000 bp) DNA products which represented a total or partial sequence of each of CO-I, CO-11, Cyt-B, ND-1, 12s rRNA, 16s rRNA, and some tRNAs. PCR-RFLP was performed in some variable mtDNA regions with 8 kinds of 4bp recognizing restriction enzymes. Different populations from Andong, Kyungsan, and Sunchun did not show any restriction site polymorphisms but had some length variation in certain regions of mtDNA.

• Parasites, Hosts and Diseases
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• v.46 no.3
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• pp.157-164
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• 2008

Three Acanthamoeba isolates (KA/E9, KA/E17, and KA/E23) from patients with keratitis were identified as Acanthamoeba triangularis by analysis of their molecular characteristics, a species not previously recognized to be a corneal pathogen. Epidemiologic significance of A. triangularis as a keratopathogen in Korea has been discussed. Morphologic features of Acanthamoeba cysts were examined under a microscope with differential interference contrast (DIC) optics. Mitochondrial DNA (mtDNA) of the ocular isolates KA/E9, KA/E17, and KA/E23 were digested with restriction enzymes, and the restriction patterns were compared with those of reference strains. Complete nuclear 188 and mitochondrial (mt) 16S rDNA sequences were subjected to phylogenetic analysis and species identification. mtDNA RFLP of 3 isolates showed very similar patterns to those of SH621, the type strain of A. triangularis. 16S and 18S rDNA sequence analysis confirmed 3 isolates to be A. triangularis. 18S rDNA sequence differences of the isolates were 1.3% to 1.6% and those of 16S rDNA, 0.4% to 0.9% from A. triangularis SH621. To the best of our knowledge, this is the first report, confirmed by 18S and 16S rDNA sequence analysis, of keratitis caused by A. triangularis of which the type strain was isolated from human feces. Six isolates of A. triangularis had been reported from contaminated contact lens cases in southeastern Korea.

• BMB Reports
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• v.38 no.4
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• pp.491-499
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• 2005

DNA-based molecular markers for differentiation of five penaeid shrimps (Penaeus monodon, P. semisulcatus, Feneropenaeus merguiensis, Litopenaeus vannamei and Marsupenaeus japonicus) were developed based on polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and single-stranded conformation polymorphism (SSCP) of 16S ribosomal (r) DNA. Differentiation of P. monodon, P. semisulcatus and L. vannamei can be unambiguously carried out by PCR-RFLP of 16S $rDNA_{560}$ whereas P. semisulcatus and M. japonicus shared a BABB mitotype. These shrimps were successfully discriminated by SSCP analysis of 16S $rDNA_{560}$. Nevertheless, the amplification success for L. vannamei and F. merguiensis was not consistent when tested against larger sample sizes. As a result, 16S $rDNA_{560}$ of an individual representing the most common mitotype of each species was cloned and sequenced. The new primer pair was designed and tested against the large sample sizes (312 bp product, N = 185). The amplification success was consistent across all species. PCR-RFLP of 16S $rDNA_{312}$ was as effective as that of 16S $rDNA_{560}$. Differentiation of all shrimp species were successfully carried out by SSCP analysis.

• Animal Systematics, Evolution and Diversity
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• v.36 no.3
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• pp.268-273
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• 2020

A spionid polychaete, Boccardiella hamata (Webster, 1879) has been found from mud in crevices between the shells of oysters and adherent substrates in South Korea. The sequences of mitochondrial DNA (mtDNA) cytochrome c oxidase subunit 1 (CO1), 16S ribosomal DNA (16S), and the nuclear 18S ribosomal DNA (18S) from Korean individuals of Boccardiella hamata were determined in the present study. The molecular analysis based on the 18S rRNA gene sequences showed clear separation among the spionid polychaete species, and the sequences of Korean and Japanese individuals are completely identical. The morphological diagnosis and photographs of B. hamata are also provided.

• Parasites, Hosts and Diseases
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• v.44 no.2 s.138
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• pp.117-125
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• 2006

Genetic diversity of 18 Acanthamoeba isolates from ocean sediments was evaluated by comparing mitochondrial (mt) DNA RFLP, 18S rDNA sequences and by examining their cytopathic effects on human corneal epithelial cells versus reference strains. All isolates belonged to morphologic group II. Total of 16 restriction phenotypes of mtDNA from 18 isolates demonstrated the genetic diversity of Acanthamoeba in ocean sediments. Phylogenetic analysis using 18s rDNA sequences revealed that the 18 isolates were distinct from morphological groups I and III. Fifteen isolates showed close relatedness with 17 clinical isolates and A. castellanii Castellani and formed a lineage equivalent to T4 genotype of Byers' group. Two reference strains from ocean sediment, A. hatchetti BH-2 and A. griffini S-7 clustered unequivocally with these 15 isolates. Diversity among isolates was also evident from their cytopathic effects on human corneal cells. This is the first time describing Acanthamoeba diversity in ocean sediments in Korea.

• Journal of Animal Science and Technology
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• v.46 no.6
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• pp.937-946
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• 2004

Duroc is widely used to improve the meat quality and productivity. To elucidate the phylogenetic relation and the sequence specificity for the maternal property, the complete sequence of mitochondrial genome was determined and the population diversity of Duroc was investigated in this study. The length of mtDNA tested is 16,584-bp. There are several insertion/deletion mutations in the control region and coding regions for tRNA and rRNA, respectively, but not in peptide-coding regions. Four peptide-coding genes(COⅡ, COⅢ, ND3 and ND4) showed incomplete termination codon sequences such as T--, and two(ND2 and ND4L) did alternative initiation codons(AIC), respectively. Especially, the initiation codon sequences of ND2 gene were polymorphic in this population. Polymorphisms were detected in 11-bp duplication motif within control region as well as ND2 and CYTB. Variation patterns observed from the tests on three mtDNA regions were linked completely and then two haplotypes obtained from combining the data dividing this population. Duroc mtDNA is observed at the European pig cluster in the phylogenetic tree, however, the results from the population analyses supported previous opinions. This study suggests that the breed Duroc was mainly originated from the European pig lineage, and Asian lineage was also used to form the pig breed Duroc as maternal progenitors.

• Parasites, Hosts and Diseases
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• v.43 no.1 s.133
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• pp.7-13
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• 2005

The taxonomy of Acanthamoeba spp., an amphizoic amoeba which causes granulomatous amoebic encephalitis and chronic amoebic keratitis, has been revised many times. The taxonomic validity of some species has yet to be assessed. In this paper, we analyzed the morphological characteristics, nuclear 18s rDNA and mitochondrial 16s rDNA sequences and the Mt DNA RFLP of the type strains of four Acanthamoeba species, which had been previously designated as A. divionensis, A. parasidionensis, A. mauritaniensis, and A. rhysodes. The four isolates revealed characteristic group II morphology. They exhibited 18S rDNA sequence differences of $0.2-1.1\%$ with each other, but more than $2\%$ difference from the other compared reference strains. Four isolates formed a different clade from that of A. castellanii Castellani and the other strains in morphological group lion the phylogenetic tree. In light of these results, A. paradivionensis, A. divionensis, and A. mauritaniensis should be regarded as synonyms for A. rhysodes.

• International Journal of Industrial Entomology and Biomaterials
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• v.2 no.1
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• pp.37-53
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• 2001

Two regions of mtDNA genome, cytochrome oxidase subunit I (COI) and 165 ribosomal RNA (165 rRNA) genes, were sequenced for 15 species of the long-horned beetle belonging to four subfamilies and geographic samples of mulberry longicorn beetle, Apriona germari, from two localities in Korea. Ten samples of A. germari collected from Suwon and Busan revealed three COI haplotypes ranging in nucleotide divergence of 0.3% to 0.5%, and the two populations shared one common COI haplotype (80%). The sequence divergence among 15 species of the long-horned beetle was much higher in COI gene (12.3%∼39.4%) than 16S rRNA gene (7.2% to 23.1), and the maximum value in the COI gene is exceptional compared with other relevant studies, including that of Coleoptera. The greatly increased divergence in the COI gene, in facto was stemmed from a peculiar sequence of Prionus insularis belonging to Prioninne, divergence of which ranges from 31.2% to 39.3% from other species. We discussed possible reason of the divergence in this species. Due to the abnormality of COI gene divergence, decrease in phylogenetic signal was severe in COI nucleotide and, subsequently, the converted amino acid sequences, rendering us to put more confidence on the 16S5 rRNA gene data. Although the molecular phylogeny confidently supports the monophyletic origin of Lepturinae, the presence of discrepancy between molecular data and traditional taxonomic views also is a testable hyothesis. One such discrepancy includes taxonomic position of Sophronica obrioides and Theophilea cylindricollis belonging to Lamiinae.

• Korean Journal of Environmental Biology
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• v.22 no.1
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• pp.66-74
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• 2004

In order to clarify intra-and inter-specific variation of Korean Rana species, the partial DNA sequences of mitochondrial 16S rDNA gene were determined from 6 Korean and 1 Japanese Rana species, DNA sequences from Korean and Japanese species were comparison-analysed within, and also with the sequences from three species of Japanese brown frogs. DNA similarities were calculated as 91.3∼97.3％ among brown frog (R. amurensis coreana, R. dybowskii and R. huanrenensis), as 96.11∼97.26％ among pond frogs (R. nigromaculata and R. planeyi chosenica). Genetic distance of pond frog and wrinkle fyog (R. rugosa) were near than that of pond frog and brown frog. Two clusters were formed brown frogs and the other group by neigh-bor-joining and maximum-likelihood analysis, also the populations of R. nigromaculata were well distinguished between Korean peninsula and Korean island. But result from maximum-likelihood analysis slightly differed from neighbor-joining to cluster of R. rugosa. Further analyses for their population will be necessary to study the phylogenetic status.

• Korean journal of applied entomology
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• v.39 no.4
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• pp.211-226
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• 2000

Genetic divergence and phylogenetic relationships among the major Korean fireflies (Hotaria papariensis, Luciola lateralis, and Pyrocoelia rufa) were studied. A portion of mitochondrial COI (403 bp) and 165 rRNA (490~504 bp) genes were sequenced, and the GenBank-registered, homologous 165 rRNA sequences of Japanese fireflies were compared (27 species of Lampyridae, one of Lycidae, and one of Rhgophthalmidae). Greatest DNA and/or amino acid sequence divergence was found when P rufa, belonging to Lampyrinae was compared with H. papariensis and L. lateralis, both belong-ing to Luciolinae, confirming the current taxonomic status of the species. In the PAUP and PHYLIP analyses with 165 rRNA data, grouping of the two geographic samples of H. papariensis with H. tsushimana validate the use of generic name, Hotaria. Nevertheless, lack of sister-group relationship of the two geographic samples of H. papariensis renders further investigation on this group . Although the Korean and Japanese L. lateralis formed a strong monophyletic group, a substantial genetic differentiation was detected between them (2.9% of 165 rRNA gene sequence divergence). Finally, the geographic samples of Korean p. rufa strongly formed a group with Japanese p. rufa, warranting the use of generic name, Pyrocoelia, but the genetic distance observed between the Cheju-Island individual and all others requires further investigation on this subject. Summarized, this study supports the current taxonomic status of the Korean fireflies in that each respectively formed a strong monophyletic group with its own species or genus.