• Journal of Microbiology
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• v.43 no.5
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• pp.430-436
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• 2005

In this study, the prevalence and quantity of a latent pseudorabies virus (PrV) infection in the nervous tissues of randomly selected pigs was determined via nested and real-time PCR. The nervous tissues, including the trigeminal ganglion (TG), olfactory bulb (OB), and brain stem (BS), were collected from the heads of 40 randomly selected pigs. The majority of the nervous tissues from the selected pigs evidenced a positively amplified band on nested PCR. In particular, nested PCR targeted to the PrV glycoprotein B (gB) gene yielded positive results in all of the BS samples. Nested PCR for either the gE or gG gene produced positive bands in a less number of nervous tissues ($57.5\%$ and $42.5\%$, respectively). Real-time PCR revealed that the examined tissues harbored large copy numbers of latent PrV DNA, ranging between $10^{0.1}\;and\;10^{7.2}(1-1.58{\times}10^7)$ copies per $1{\mu}g$ of genomic DNA. Real-time PCR targeted to the PrV gE gene exhibited an accumulated fluorescence of reporter dye at levels above threshold, thereby indicating a higher prevalence than was observed on the nested PCR ($100\%$ for BS, $92\%$ for OB, and $85\%$ for TG). These results indicate that a large number of farm-grown pigs are latently infected with a field PrV strain with a variety of copy numbers. This result is similar to what was found in association with the human herpes virus.

• Applied Biological Chemistry
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• v.36 no.4
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• pp.315-317
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• 1993

To understand the molecular structure and pathogenesis mechanism of Korean garlic viruses (GV), virus particles were isolated from field-grown garlic leaves and RNA genome was isolated from them. It was used for constructing cDNA library for GV. Several cDNA clones for GV were isolated and classified into 4 different groups on the basis of cross Southern hybridization. Northern blot analysis of GV RNA with one of these cDNA clones shows that the clone is a cDNA for GV RNA.

• ALGAE
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• v.30 no.2
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• pp.81-87
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• 2015

Recent studies have shown the importance of viruses as potential sources of plankton mortality, which affect primary production and biogeochemical functions of their hosts. Here, we report basic characteristics of a novel virus (Stephanopyxis palmeriana virus: SpalV) that causes lysis of a culture of the diatom S. palmeriana, which was isolated in Jaran Bay, Korea, in August 2008. SpalV is a round-shaped viral particle ~25-30 nm in diameter that propagates in its host's cytoplasm. In addition, it shows species-specific infectivity among the tested diatom species. The burst size and latent period are estimated to be roughly 92 infectious units $cell^{-1}$ and <80 h, respectively.

• The Plant Pathology Journal
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• v.31 no.2
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• pp.186-191
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• 2015

Diatoms are a major component of the biological community, serving as the principal primary producers in the food web and sustaining oxygen levels in aquatic environments. Among marine planktonic diatoms, the cosmopolitan Skeletonema costatum is one of the most abundant and widespread species in the world's oceans. Here, we report the basic characteristics of a new diatom-infecting S. costatum virus (ScosV) isolated from Jaran Bay, Korea, in June 2008. ScosV is a polyhedral virus (45-50 nm in diameter) that propagates in the cytoplasm of host cells and causes lysis of S. costatum cultures. The infectivity of ScosV was determined to be strain- rather than species-specific, similar to other algal viruses. The burst size and latent period were roughly estimated at 90-250 infectious units/cell and <48 h, respectively.

• Journal of Microbiology and Biotechnology
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• v.15 no.5
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• pp.1110-1114
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• 2005

Six viruses of the genera Carlavirus (Garlic mosaic virus, GarMV, and Garlic latent virus, GarLV), Allexivirus (Garlic virus X, GarV-X, and Garlic mite-borne filamentous virus, GarMbFV) and Potyvirus (Leek yellow stripe virus, LYSV, and Onion yellow dwarf virus, OYDV) from Korean garlic plants with mosaic symptoms were simultaneously detected by multiplex RT-PCR and subsequently sequenced. An immunocapture RT-PCR for the detection of GarLV, LYSV, and OYDV was also performed. The coat protein phylogenetic analysis of the garlic viruses showed that the Korean isolates were most closely related to the isolates from China, Japan, Brazil, and Argentina. This study is the first report for the differentiation of six garlic viruses in Korea by simultaneous detection using multiplex RT-PCR.

• Korean journal of applied entomology
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• v.16 no.2 s.31
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• pp.87-92
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• 1977

A barley virus disease has been severe in central Korea since 1963. To investigate the causal virus, examination of host ranges, transmission by insect vectors and · electron microscopy were conducted. In electron microscopy, particles identical with northern cereal mosaic virus were observed. The size of baciliform particles ranged from 300nm to 370nm in length and 57-60nm in diameter. The virus was transmitted by the small brown planthopper Laodelphax striatellus (Fallen). The latent period in the vector was seven to nineteen days, with 10 days the most prevalent. Barley, corn, wheat, rye, and oats were susceptible to the virus when inoculated by the insect vectors. It was concluded that the disease agent of the barley disease in Korea is northern cereal mosaic virus. This is the first known report of this disease in Korea.

• The Plant Pathology Journal
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• v.37 no.3
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• pp.258-267
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• 2021

Asian pear (Pyrus pyrifolia) is a widely cultivated and commercially important fruit crop, which is occasionally subject to severe economic losses due to latent viral infections. Thus, the aim of the present study was to examine and provide a comprehensive overview of virus populations infecting a major pear cultivar ('Singo') in Korea. From June 2017 to October 2019, leaf samples (n = 110) of pear trees from 35 orchards in five major pear-producing regions were collected and subjected to RNA sequencing. Most virus-associated contigs matched the sequences of known viruses, including apple stem grooving virus (ASGV) and apple stem pitting virus (ASPV). However, some contigs matched the sequences of apple green crinkle-associated virus and cucumber mosaic virus. In addition, three complete or nearly complete genomes were constructed based on transcriptome data and subjected to phylogenetic analyses. Based on the number of virus-associated reads, ASGV and ASPV were identified as the dominant viruses of 'Singo.' The present study describes the virome of a major pear cultivar in Korea, and looks into the diversity of viral communities in this cultivar. This study can provide valuable information on the complexity of genetic variability of viruses infecting pear trees.

• Research in Plant Disease
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• v.23 no.1
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• pp.75-81
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• 2017

In May 2016, 24 peach samples showing abnormal and virus like symptoms were collected in one of major peach producing area, Yeongcheon-si, Gyeongsangbuk-do, Korea. We performed RT-PCR diagnosis for confirmation of viral infection. The diagnostic targets are 17 species of viruses and viroids that quarantine and high risk pathogens when it occur. As a results, seven species of viruses and viroids, including an unreported (Apricot pseudo-chlorotic leaf spot virus, APCLSV) and a quarantine (Peach latent mosaic viroid, PLMVd) species in Korea, were detected. For the sequence analysis of unreported virus, APCLSV, the sequence of coat protein gene were amplified and cloned. The sequence showed 97% nucleotide identity with other APCLSV isolates and compared with other seven species of reported Trichoviruses. This virus was classified as APCLSV based on the sequence and phylogenetic analysis. This isolate was named Yeongcheon. As patterns of APCLSV occurrence, all samples that APCLSV detected were co-infected with Apple chlorotic leaf spot virus (ACLSV). As properties of ACLSV, APCLSV has high possibility of wide spread disease in fruit tree farms in Korea. Therefore, it is necessary to do related researches, such as infection route and influence of disease in commercial orchards.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11b
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• pp.262-264
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• 2005

인유두종 바이러스(Human Papillomavirus: HPV)는 사마귀로부터 생식기 및 배설기의 침윤성 암에 이르기까지 여러 질병과 연관되어 있음이 알려져 있다. 현재 200종 이상이 알려져 있고, 이 중 85개는 전체 유전자가 밝혀져 있다. HPV 감염 시 만들어지는 단백질 중 E6. E7 단백질은 암 억제 유전자(p53, pRb)에 결합하여 세포의 암 억제 기능을 저하시키고 이로 인해 암을 발생시킨다. 본 논문은 암 발생과 밀접한 관련이 있는 HPV의 E6 단백질 서열과 HPV 유형(HPV Type)을 가지고, PLSA (Probabilistic Latent Semantic Analysis) 방법을 이용하여 HPV를 클러스터링(clustering) 해 보았다. 실험 결과, 특정 클러스터는 질병과 밀접하게 연관되어 있으며, 이와 관련된 주요 서열 분석이 가능함을 보여주고 있다.

• Research in Plant Disease
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• v.15 no.1
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• pp.8-12
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• 2009

Virus disease surveys of strawberries cultivated and preserved as germplasm resources in Korea was conducted during 2007-2008. Virus detection was conducted by RT-PCR using total RNAs extracted from strawberry samples. We detected the infection with Strawberry mild yellow edge virus (SMYEV), Strawberry mottle virus (SMoV), Strawberry vein banding virus (SVBV) and Strawberry pallidosis associated virus (SPaV) while no infection with Strawberry crinkle virus (SCV), Strawberry necrotic shock virus (SNSV), Strawberry latent ring spot virus (SLRSV) and Arabis mosaic virus (ArMV) was observed. The infection rate of virus disease on 4 cultivars including Seolhyang, Maehyang, Gumhyang, and Dahong, bred in Korea, was 0.1, 1.9, 0, and 0%, respectively. Surprisingly, however, cultivar Red Peal introduced from Japan in 1997 revealed 48.3% virus infection rate. SMYEV, SMoV and SPaV were also identified in strawberries growing in the farm fields of Korea. In the field, however, SMYEV was the most predominant virus (97.4%) among those 3 identified viruses. SVBV was detected only in strawberry kept as a germplasm.