• Journal of Microbiology and Biotechnology
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• v.28 no.5
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• pp.796-808
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• 2018

The intracellular bacterium Wolbachia pipientis is widespread in arthropods. Recently, possibilities of novel Wolbachia-mediated hosts, their distribution, and natural rate have been anticipated, and the coconut leaf beetle Brontispa longissima (Gestro) (Coleoptera: Chrysomelidae), which has garnered attention as a serious pest of palms, was subjected to this interrogation. By adopting Wolbachia surface protein (wsp) and multilocus sequence type (MLST) genotypic systems, we determined the Wolbachia infection density within host developmental stages, body parts, and tissues, and the results revealed that all the tested samples of B. longissima were infected with the same Wolbachia strain (wLog), suggesting complete vertical transmission. The MLST profile elucidated two new alleles (ftsZ-234 and coxA-266) that define a new sequence type (ST-483), which indicates the particular genotypic association of B. longissima and Wolbachia. The quantitative real-time PCR analysis revealed a higher infection density in the eggs and adult stage, followed by the abdomen and reproductive tissues, respectively. However, no significant differences were observed in the infection density between sexes. Moreover, the wsp and concatenated MLST alignment analysis of this study with other known Wolbachia-mediated arthropods revealed similar clustering with distinct monophyletic supergroup B. This is the first comprehensive report on the prevalence, infection dynamics, and phylogeny of the Wolbachia endosymbiont in B. longissima, which demonstrated that Wolbachia is ubiquitous across all developmental stages and distributed in the entire body of B. longissima. Understanding the Wolbachia infection dynamics would provide useful insight to build a framework for future investigations, understand its impacts on host physiology, and exploit it as a potential biocontrol agent.

• International Journal of Industrial Entomology and Biomaterials
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• v.23 no.1
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• pp.155-166
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• 2011

The leaf beetle, $Chrysolina$ $aurichalcea$ (Coleoptera: Chysomelidae), is a pest damaging plants of Compositae. In order to understand the genetic diversity and geographic variation we sequenced a portion of mitochondrial COI gene (658 bp) and complete nuclear internal transcribed spacer 2 (ITS2) of the species collected from seven Korean localities. A total of 17 haplotypes (CACOI01~CACOI17), with the maximum sequence divergence of 3.04% (20 bp) were obtained from COI gene sequence, whereas 16 sequence types (ITS2CA01~ITS2CA16), with the maximum sequence divergence of 2.013% (9 bp) were obtained from ITS2, indicating substantially larger sequence divergence in COI gene sequence. Phylogenetically, the COI gene provided two haplotype groups with a high nodal support (${\geq}87%$), whereas ITS2 provided only one sequence type group with a high nodal support (${\geq}92%$). The result of COI gene sequence may suggest the presence of historical biogeographic barriers that bolstered genetic subdivision in the species. Different grouping pattern between COI gene and ITS2 sequences were interpreted in terms of recent dispersal, reflected in the ITS2 sequence. Finding of unique haplotypes and sequence types only from Beakryeng-Islet population was interpreted as an intact remnant of ancient polymorphism. As more samples are analyzed using further hyper-variable marker, further fruitful inference on the geographic contour of the species might be available.

• Molecules and Cells
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• v.25 no.1
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• pp.43-49
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• 2008

Cancer Osaka thyroid, also known as Tpl-2 (Cot) is a member of the MAP3K kinase family and plays a key role in the regulation of the immune response to pro-inflammatory stimuli such as lipopolysaccharide (LPS) and tumour necrosis $factor-{\alpha}$ ($TNF-{\alpha}$). A series of Cot constructs with an N-terminal 6xHis tag were transiently expressed in HEK293 cells: $Cot_{130-399}$ (kinase domain), $Cot_{1-388}$ (N-terminal and kinase do-mains), $Cot_{1-413}$, $Cot_{1-438}$ (containing a putative PEST sequence), $Cot_{1-457}$ (containing both PEST and degron sequences) and $Cot_{1-467}$ (full-length protein). These Cot proteins were pulled down using an anti-6xHis antibody and separated by 2D electrophoresis. The gels were silver-stained and 21 proteins were detected that did not appear, or had substantially reduced intensity, in the control sample. Three of these were identified by MS and MS/MS analysis as Hsp90, Hsp70 and Grp78. Hsp90 appeared to bind to the kinase domain of Cot and this interaction was further investigated using co-immuno-precipitation with both overexpressed Cot in HEK293 cells and endogenous Cot in Hela cells.

• The Korean Journal of Mycology
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• v.37 no.2
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• pp.139-143
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• 2009

Several entomopathogenic fungi have been exploited to be developed into biological control agents in insect pest management. The beet armyworm, Spodoptera exigua, is a serious insect pest infesting various crops, but not effectively controlled by commercial chemical pesticides due to its high insecticide resistance. A fungal isolate was isolated from S. exigua larvae collected from cabbage field in Andong, Korea. The fungus could be cultured in potato dextrose agar. Larvae of S. exigua injected with the cultured conidia showed a potent entomopathogenicity. To identify the fungus isolate, its internal transcribed space (ITS) and surrounding partial 18S/28S regions were sequenced. The ITS sequence was highly matched (99%) to that of Nomuraea rileyi. Morphological characters of its hyphae and conidia were well fit to those of known N. rileyi. This study reports the first record of an entomopathogenic fungus, N. rileyi, in Korea.

• Korean journal of applied entomology
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• v.50 no.4
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• pp.325-333
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• 2011

This study focused on the green peach aphid, Myzus persicae, as an indicator pest in Chinese cabbage cultivation to develop a genetic marker. We hypothesized that M. persicae gene flow is related to climate change. Genetic variation was analyzed using five local populations collected at different altitudes (157 m, 296 m, 560 m, 756 m and 932 m above sea level) in Hoengseong, Pyeongchang, and Gangneung areas, plus a laboratory strain used as an outgroup. There were no differences in ecological characteristics among strains. Esterase isozyme pattern and inter-simple sequence repeat (ISSR) PCR results showed significantly different bands between laboratory and wild, local populations. However, there was no difference among local populations. Partial fragments of ribosomal RNA (rRNA) and mitochondrial cytochrome oxidase I (mtCO I) were amplified and their nucleotide sequence was analyzed. Single nucleotide polymorphisms (SNPs) were detected in internal transcribed spacer-2 (ITS-2) and mtCO I regions among the five local populations. These SNPs can be use to discriminate different populations of M. persicae to monitor gene flow.

• International Journal of Industrial Entomology and Biomaterials
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• v.14 no.2
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• pp.107-112
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• 2007

The mole crickets, Gryllotalpa, are insect pest distributed in the world. In Korea, G. orientalis was reported to occur, but previous ecological studies suggested the presence of two ecological types. To test this hypothesis, we sequenced a portion of mitochondrial (mt) genome from 48 G. orientali individuals collected over five Korean localities: Busan, Suwon, Okchon, Wonju, and Gangneung. From the sequence analysis, only two haplotypes were obtained, but the sequence divergence between the two haplotypes was 11 %, suggesting the presence of two distinct genetic groups in Korea. Although the population of Busan, Okchon, Wonju, and Gangneung was identified as a single haplotype, but that of Suwon was occupied by both hapotypes. Considering sequence divergence of other insect species occurring in Korea, the divergence estimate found between the two haplotypes seems to be too large to be considered as identical species. This result may suggest that the two differentiated haplotypes found in this study may reflect the previously reported two ecological types found in Suwon, Korea. To further understand the genetic divergence of the two phylogenetic groups, analysis of more variable regions of G. orientalis genome is required.

• Mycobiology
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• v.41 no.1
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• pp.59-62
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• 2013

Japanese pine sawyer beetle (Monochamus alternatus) is an economically important pest in coniferous trees. Ophiostoma ips was isolated from the beetle and identified based on analysis of morphological properties and the ${\beta}$-tubulin gene sequence. The fungus easily produced perithecia with a long neck on malt extract agar and its ascospores were rectangular shaped. This is first report of Ophiostoma species associated with the pinewood nematode vector beetle in Korea.

• Mycobiology
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• v.41 no.4
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• pp.245-247
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• 2013

The ambrosia beetle, Platypus koryoensis, is an economically important pest affecting oak trees in Korea. Candida kashinagacola was isolated from galleries of the beetle in oak wood and identified by analyses of morphology, physiological properties, and nucleotide sequence of the large subunit ribosomal DNA. This is the first report on Candida species associated with oak wilt disease vectored by the ambrosia beetle, Platypus koryoensis, in Korea.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.04a
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• pp.66-66
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• 2003

The coleoptera is the most species-rich order of animals. Relatively little is known about Coleoptera genes and genome. We describe here the construction and DNA sequencing of cDNA libraries from Protaetia brevizarsis, a fruit tree pest in Korea. We sequenced and analyzed 3072 ESTs from wholebody of Protaetia brevizarsis larvae. (omitted)

• The Plant Pathology Journal
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• v.34 no.5
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• pp.356-366
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• 2018

The red flour beetle, Tribolium castaneum, is one of the most common and economically important pests of stored cereal products worldwide. Furthermore, these beetles can act as vectors for several fungal post-harvest diseases. In this study, we collected T. castaneum from 49 rice processing complexes (RPCs) nationwide during 2016-2017 and identified contaminating fungal species on the surface of the beetles. Five beetles from each region were placed on potato dextrose agar media or Fusarium selection media after wet processing with 100% relative humidity at $27^{\circ}C$ for one week. A total of 142 fungal isolates were thus collected. By sequence analysis of the internal transcribed spacer region, 23 fungal genera including one unidentified taxon were found to be associated with T. castaneum. The genus Aspergillus spp. (28.9%) was the most frequently present, followed by Cladosporium spp. (12.0%), Hyphopichia burtonii (9.2%), Penicillium spp. (8.5%), Mucor spp. (6.3%), Rhizopus spp. (5.6%), Cephaliophora spp. (3.5%), Alternaria alternata (2.8%) and Monascus sp. (2.8%). Less commonly identified were genera Fusarium, Nigrospora, Beauveria, Chaetomium, Coprinellus, Irpex, Lichtheimia, Trichoderma, Byssochlamys, Cochliobolus, Cunninghamella, Mortierella, Polyporales, Rhizomucor and Talaromyces. Among the isolates, two known mycotoxin-producing fungi, Aspergillus flavus and Fusarium spp. were also identified. This result is consistent with previous studies that surveyed fungal and mycotoxin contamination in rice from RPCs. Our study indicates that the storage pest, T. castaneum, would play an important role in spreading fungal contaminants and consequently increasing mycotoxin contamination in stored rice.