• Microbiology and Biotechnology Letters
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• v.26 no.1
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• pp.23-33
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• 1998

The entire sequence of a 4,214,810 bp genome of the Bacillus subtilis 168 has been determined by an international project, and the completion has been announced on July 19, 1997. For the sequencing project an international consortium was established and 25 European, 7 Japanese laboratories, 2 biotechnology companies, and our laboratory participated in the project. Within this framework we determined the complete nucleotide sequence of a 53,289 bp fragment upstream of the odhA gene (181 $^{\circ}$) of the B. subtilis 168 chromosome. On the basis of the published DNA sequences of the B. subtilis sspC and odhA genes, we obtained genomic fragments by plasmid rescue and long-range PCR. The sequenced fragment contains 56 putative open reading frames (designated yojA-yolI and 9 known genes (sspC, cge cluster, orfE5, orfRMl and odhA), in which we found many interesting features. In addition, the entire nucleotide sequence of a 53,289 bp region enabled us to revise the current genetic map of this region.

• Korean Journal of Ichthyology
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• v.33 no.4
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• pp.217-225
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• 2021

The family Platycephalidae is a taxonomic group of economically important demersal flathead fishes that predominantly occupy tropical or temperate estuaries and coastal environments of the Indo-Pacific oceans and the Mediterranean Sea. In this study, we for the first time analyzed the complete mitochondrial genome (mitogenome) of the flathead Platycephalus cultellatus Richardson, 1846 from Vietnam by Next Generation Sequencing method. Its mitogenome was 16,641 bp in total length, comprising 13 protein-coding genes (PCGs), two ribosomal RNA genes, and 22 transfer RNA genes. The gene composition and order of the mitogenome were identical to those of typical vertebrates. The phylogenetic trees were reconstructed based on the concatenated nucleotide sequence matrix of 13 PCGs and the partial sequence of a DNA barcoding marker, cox1 in order to determine its molecular phylogenetic position among the order Scorpaeniformes. The phylogenetic result revealed that P. cultellatus formed a monophyletic group with species belonging to the same family and consistently clustered with one nominal species, P. indicus, and two Platycephalus sp. specimens. Besides, the cox1 tree confirmed the taxonomic validity of our specimen by forming a monophyletic clade with its conspecific specimens. The mitogenome of P. cultellatus analyzed in this study will contribute valuable information for further study on taxonomy and phylogeny of flatheads.

• The Plant Pathology Journal
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• v.36 no.5
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• pp.468-475
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• 2020

Malva vein clearing virus (MVCV) is a member of the Potyvirus species, and has a negative impact on the aesthetic development of Alcea rosea. It was first reported in Germany in 1957, but its complete genome sequence data are still scarce. In the present work, A. rosea leaves with vein-clearing and mosaic symptoms were sampled and analyzed with small RNA deep sequencing. By denovo assembly the raw sequences of virus-derived small interfering RNAs (vsiRs) and whole genome amplification of malva vein cleaning virus SX strain (MVCV-SX) by specific primers targeting identified contig gaps, the full-length genome sequences (9,645 nucleotides) of MVCV-SX were characterized, constituting of an open reading frame that is long enough to encode 3,096 amino acids. Phylogenetic analysis showed that MVCV-SX was clustered with euphorbia ringspot virus and yam mosaic virus. Further analyses of the vsiR profiles revealed that the most abundant MVCV-vsiRs were between 21 and 22 nucleotides in length and a strong bias was found for "A" and "U" at the 5′-terminal residue. The results of polarity assessment indicated that the amount of sense strand was almost equal to that of the antisense strand in MVCV-vsiRs, and the main hot-spot region in MVCV-SX genome was found at cylindrical inclusion. In conclusion, our findings could provide new insights into the RNA silencing-mediated host defence mechanism in A. rosea infected with MVCV-SX, and offer a basis for the prevention and treatment of this virus disease.

• Animal cells and systems
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• v.5 no.3
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• pp.163-177
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• 2001

Most, if not all, aphids harbor intracellular bacterial symbionts, called Buchnera, in their bacteriocytes, huge cells differentiated for this purpose. The association between Buchnera and aphids is so intimate, mutualistic and obligate that neither of them can any longer reproduce independently. Buchnera are vertically transmitted through generations of the host insects. Evidence suggests that Buchnera were acquired by a common ancestor of aphids 160-280 million years ago, and have been diversified, since then, in parallel with their aphid hosts. Molecular phylogenetic analyses indicate that Buchnera belong to the g subdivision of the Proteobacteria. Although Buchnera are close relatives of Escherichia coli, they contain move than 100 genomic copies per cell, and their genome size is only one seventh that of E. coli. The complete genome sequence of Buchnera revealed that their gene repertoire is quite different from those of parasitic bacteria such as Mycoplasma, Rickettsia and Chlamydia, though their genome sizes have been reduced to a similar extent. Whereas these parasitic bacteria have lost most genes for the biosynthesis of amino acids, Buchnera retain many of them. In particular, Buchnera's gene repertoire is characteristic in the richness of the genes for the biosynthesis of essential amino acids that the eukaryotic hosts are not able to synthesize, reflecting a nutritional role played by these symbionts. Buchnera, when housed in the bacteriocyte, selectively synthesize a large amount of symbionin, which is a homolog of GroEL, the major stress protein of E. coli. Symbionin not only functions as molecular chaperone, like GroEL, but also has evolutionarily acquired the phosphotransferase activity through amino acid substitutions. Aphids usually profit from Buchnera's fuction as a nutritional supplier and, when faced with an emergency, consume the biomass of Buchnera cells as nutrient reserves.

• Journal of Plant Biotechnology
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• v.33 no.3
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• pp.153-160
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• 2006

Brassica rape is an important species used as a vegetable, oil, and fodder worldwide. It is related phylogenically to Arabidopsis thaliana, which has already been fully sequenced as a model plant. The 'Multinational Brassica Genome Project (MBGP)'was launched by the international Brassica community with the aim of sequencing the whole genome of B. rapa in 2003 on account of its value and the fact that it has the smallest genome among the diploid Brassica. The genome study was carried out not only to know the structure of genome but also to understand the function and the evolution of the genes comprehensively. There are two mapping populations, over 1,000 molecular markers and a genetic map, 2 BAC libraries, physical map, a 22 cDHA libraries as suitable genomic materials for examining the genome of B. rapa ssp. pekinensis Chinese cabbage. As the first step for whole genome analysis, 220,000 BAC-end sequences of the KBrH and KBrB BAC library are achieved by cooperation of six countries. The results of BAC-end sequence analysis will provide a clue in understanding the structure of the genome of Brassica rapa by analyzing the gene sequence, annotation and abundant repetitive DHA. The second stage involves sequencing of the genetically mapped seed BACs and identifying the overlapping BACs for complete genome sequencing. Currently, the second stage is comprises of process genetic anchoring using communal populations and maps to identify more than 1,000 seed BACs based on a BAC-to-BAC strategy. For the initial sequencing, 629 seed BACs corresponding to the minimum tiling path onto Arabidopsis genome were selected and fully sequenced. These BACs are now anchoring to the genetic map using the development of SSR markers. This information will be useful for identifying near BAC clones with the seed BAC on a genome map. From the BAC sequences, it is revealed that the Brassica rapa genome has extensive triplication of the DNA segment coupled with variable gene losses and rearrangements within the segments. This article introduces the current status and prospective of Korea Brassica Genome Project and the bioinformatics tools possessed in each national team. In the near future, data of the genome will contribute to improving Brassicas for their economic use as well as in understanding the evolutional process.

• Journal of Ginseng Research
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• v.44 no.1
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• pp.135-144
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• 2020

Background: Panax species are important herbal medicinal plants in the Araliaceae family. Recently, we reported the complete chloroplast genomes and 45S nuclear ribosomal DNA sequences from seven Panax species, two (P. quinquefolius and P. trifolius) from North America and five (P. ginseng, P. notoginseng, P. japonicus, P. vietnamensis, and P. stipuleanatus) from Asia. Methods: We conducted phylogenetic analysis of these chloroplast sequences with 12 other Araliaceae species and comprehensive comparative analysis among the seven Panax whole chloroplast genomes. Results: We identified 1,128 single nucleotide polymorphisms (SNP) in coding gene sequences, distributed among 72 of the 79 protein-coding genes in the chloroplast genomes of the seven Panax species. The other seven genes (including psaJ, psbN, rpl23, psbF, psbL, rps18, and rps7) were identical among the Panax species. We also discovered that 12 large chloroplast genome fragments were transferred into the mitochondrial genome based on sharing of more than 90% sequence similarity. The total size of transferred fragments was 60,331 bp, corresponding to approximately 38.6% of chloroplast genome. We developed 18 SNP markers from the chloroplast genic coding sequence regions that were not similar to regions in the mitochondrial genome. These markers included two or three species-specific markers for each species and can be used to authenticate all the seven Panax species from the others. Conclusion: The comparative analysis of chloroplast genomes from seven Panax species elucidated their genetic diversity and evolutionary relationships, and 18 species-specific markers were able to discriminate among these species, thereby furthering efforts to protect the ginseng industry from economically motivated adulteration.

• The Plant Pathology Journal
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• v.18 no.2
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• pp.63-67
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• 2002

To understand plant-pathogen interactions, a complete set of hot pepper genes differentially expressed against pathogen attack was isolated. As an initial step, hundreds of differentially expressed cDNAS were isolated from hot pepper leaves showing non-host resistance against bacterial plant pathogens (Xanthomonas campestris pv. glycines and Pseudomonas syringae pv. syringae) using differential display reverse transcription polymerase chain reaction (DDDRT-PCR) technique. Reverse Northern and Northern blot analyses revealed that 50% of those genes were differentially expressed in pepper loaves during non-host resistance response. Among them, independent genes without redundancy were micro-arrayed for further analysis. Random EST sequence database were also generated from various CDNA libraries including pepper tissue specific libraries and leaves showing non-host hypersensitive response against X. campestris pv. glycines. As a primary stage, thousands of cDNA clones were sequenced and EST data were analyzed. These clones are being spotted on glass slide to study the expression profiling. Results of this study may further broaden knowledge on plant-pathogen interactions.

• Korean Journal of Microbiology
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• v.37 no.2
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• pp.109-113
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• 2001

As the complete genomic sequences accumulate, the use of global techniques became possible. DNA microarray is a powerful technology for measuring global mRNA levels. This method, however, does not provide information on post-translational modifications of proteins. In addition, mRNA levels do not strictly correlate with protein concentrations, especially for lower-abundance proteins. Therefore, studies at the level of transcription are not sufficient to understand cellular activity. Proteomic techniques to analyze protein expression and function at the large-scale have been developed and used. This review introduces a simple explanation for proteomic analysis and examples of how proteomics is applied in cell biology.

• Research in Plant Disease
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• v.29 no.3
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• pp.286-294
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• 2023

Biological and molecular characterization of a Korean isolate of Orthotospovirus chrysanthinecrocaulis (formerly known as chrysanthemum stem necrosis virus, CSNV) isolated from Chrysanthemum morifolium was determined using host range and sequence analysis in this study. Twenty-three species of indicator plants inoculated mechanically CSNV-Kr was investigated for determination of host range. CSNV-Kr induced various local and systemic symptoms in the inoculated plant species. CSNV-Kr could not infect three plant species and induced symptomless in systemic leaves in Nicotiana tabacum cultivars, though the plant samples reacted positively with the antiserum to CSNV by double-antibody sandwich-enzyme-linked immunosorbent assay. The complete genome sequence of CSNV-Kr was determined. The L RNA of CSNV-Kr consists of 8,959 nucleotides (nt) and encodes a putative RNA-dependent RNA polymerase. The M RNA of CSNV-Kr consists of 4,835 nt and encodes the movement protein (NSm) and the glycoprotein precursor (Gn/Gc protein). The S RNA of CNSV-Kr consists of 2,836 nt and encodes NSs protein and N protein. The Gn/Gc and N sequence of CSNV-Kr were compared with those of previously published CSNV isolates originating from different countries at nucleotide and amino acid levels. The Gn/GC sequence of CSNV-Kr shared 98.8-99.5% identity with CSNV isolated from other countries and the N sequence of CSNV-Kr shared 98.8-99.6% identity. No particular region of variability could be found in either grouping of viruses. All of the CSNV isolates did not show any relationship according to geographical origins and isolation hosts, suggesting no distinct segregation of the CSNV isolates.