• Journal of Microbiology and Biotechnology
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• v.12 no.3
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• pp.463-469
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• 2002

Rotaviruses are the world-wide leading causative agents of severe dehydrating gastroenteritis in young children and animals. The outer capsid glycoprotein VP7 and inner capsid glycoprotein VP6 of rotaviruses are highly antigenic and immunogenic. An SFV-based expression system has recently emerged as a useful tool for heterologous protein production in mammalian cells, exhibiting a much more efficient performance compared to other gene expression systems. Accordingly, the current study adopted an SFV-based expression system to express the VP7 of a group A human rotavirus from a Korean isolate, and the VP6 of a group B bovine rotavirus from a Korean isolate, in mammalian cells. The genes of the VP6 and VP7 were inserted into the SFV expression vector pSFV-1. The RNA was transcribed in vitro from pSFV-VP6 and pSFV-VP7 using SP6 polymerase. Each RNA was then electroporated into BHK-21 cells along with pSFV-helper RNA containing the structural protein gene without the packaging signal. The expression of VP6 and VP7 in the cytoplasm was then detected by immunocytochemistry. The recombinant virus was harvested by ultracentrifugation and examined under electron microscopy. After infecting BHK-21 cells with the defective viruses, the expressed proteins were separated by SDS-PAGE and analyzed by a Western blot. The results indicate that an SFV-based expression system fur the VP6 and VP7 of rotaviruses is an efficient tool for developing a diagnostic kit and/or preventive vaccine.

• Molecules and Cells
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• v.41 no.3
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• pp.198-206
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• 2018

Aortic dissection (AD) is a catastrophic disease with high mortality and morbidity, characterized with fragmentation of elastin and loss of smooth muscle cells. Although AD has been largely attributable to polymorphisms defect in the elastin-coding gene, tropoelastin (TE), other undermined factors also appear to play roles in AD onset. Here, we investigated the effects of post-transcriptional control of TE by microRNAs (miRNAs) on elastin levels in aortic smooth muscle cells (ASMC). We found that miR-144-3p is a miRNA that targets TE mRNA in both human and mouse. Bioinformatics analyses and dual luciferase reporter assay showed that miR-144-3p inhibited protein translation of TE, through binding to the 3'-UTR of the TE mRNA. Interestingly, higher miR-144-3p levels and lower TE were detected in the ASMC obtained from AD patients, compared to those from non-AD controls. In a mouse model for human AD, infusion of adeno-associated viruses (serotype 6) carrying antisense for miR-144-3p (asmiR-144-3p) under CAG promoter significantly reduced the incidence and severity of AD, seemingly through enhancement of TE levels in ASMC. Thus, our data suggest an essential role of miR-144-3p on the pathogenesis of AD.

• The Journal of Korean Society of Virology
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• v.30 no.1
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• pp.29-37
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• 2000

The aim of this study was to investigate viral etiology in dilated cardiomyopathy (DCM) by polymerase chain reaction (PCR) or nested reverse transcription PCR (RT-PCR), and characterize the enteroviral RNA presented in the clinical specimens. Twenty-eight paraffin-embedded heart tissue samples were assayed to detect cytomegalovirus, herpes simplex virus type 1, type 2, parvovirus, adenovirus, and enterovirus (EV) with each specific primer. Of these 28 patients (mean age: 27, M: 24, F: 4), 26 were histologically diagnosed as DCM and 2 as myocardial infarction (MI). Nested RT-PCR detected enteroviral RNA in 7 (26.9%) of 26 patients with DCM, and none of patients with MI. And none of DNA viruses tested were detected from the samples. Amplified products were also genotyped by single-strand conformation polymorphism (SSCP). Three subtypes can be differentiated from 7 clinical specimens. Furthermore, direct sequence analysis was performed to determine whether genetic variation of EV is present in the explanted heart tissues from patients with DCM. Although most of the sequences among the wild isolates have the greatest similarity to those of coxsackievirus B3, there are specific regions of variable sequences (no 490 - no 510). The data suggest that enterovirus may be a major viral pathogen for the DCM in Korea and nucleotide sequence data indicate that coxsackievirus B3 may be a leading etiologic agent of DCM.

• Journal of Microbiology
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• v.44 no.4
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• pp.403-408
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• 2006

The purpose of this study was to determine the efficacy of a nucleic acid sequence-based amplification (NASBA) method of detecting noroviruses in artificially and naturally contaminated shellfish. We used 58 fecal samples that tested positive for noroviruses with electron microscopy (EM) to develop an NASBA assay for these viruses. Oligonucleotide primers targeting the polymerase coding region were used to amplify the viral RNA in an isothermal process that resulted in the accumulation of RNA amplicons. These amplicons were detected by hybridization with digoxigenin-labeled oligonucleotide probes that were highly specific for genogroup I (GI) and genogroup II (GII) of noroviruses. The expected band of 327bp appeared in denaturing agarose gel without any nonspecific band. The specific signal for each amplicon was obtained through Northern blotting in many repeats. All fecal samples of which 46(79.3%) belonged to GII and 12(20.6%) belonged to GI were positive for noroviruses by EM and by NASBA. Target RNA concentrations as low as 5pg/ml were detected in fecal specimens using NASBA. When the assay was applied to artificially contaminated shellfish, the sensitivity to nucleic acid was 100pg/1.5g shellfish tissue. The potential use of this assay was also confirmed in naturally contaminated shellfish collected from different ponds in Guangzhou city of China, of which 24 (18.76%) out of 128 samples were positive for noroviruses; of these, 19 (79.6%) belonged to GII and 5 (20.4%) belonged to GI. The NASBA assay provided a more rapid and efficient way of detecting noroviruses in fecal samples and demonstrated its potential for detecting noroviruses in food and environmental samples with high specificity and sensitivity.

• Journal of Microbiology and Biotechnology
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• v.22 no.7
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• pp.1021-1028
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• 2012

In this study, a reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay was developed for the rapid, sensitive, and inexpensive detection of nervous necrosis virus (NNV) in olive flounder, Paralichthys olivaceus, in Korea. A set of six specific primers was designed to target the RNA 2 gene encoding the coat protein of Korean NNV strains. The RT-LAMP reaction successfully detected NNV after 30 min at $65^{\circ}C$. When the sensitivities among RT-LAMP, RT-PCR, and nested RTPCR were compared, the RT-LAMP was shown to be able to detect the RNA template at $2.58{\times}10^{-2}\;TCID_{50}/ml$, whereas the RT-PCR and nested RT-PCR were only able to detect the RNA template at $2.58{\times}10^2\;TCID_{50}/ml$ and $2.58TCID_{50}/ml$, respectively. Thus, the sensitivity of the RT-LAMP assay was higher than those of the RT-PCR assays. In the specificity test of the RT-LAMP, 2 genotypes of NNVs (SJNNV and RGNNV) were positive; however, no other fish viruses were positive with the primers, indicating that the RT-LAMP assay is only specific to NNV. A total of 102 olive flounder were collected from hatcheries between 2009 and 2011. The occurrence of NNV in olive flounder was determined to be 53.9% (55/102) by the RT-LAMP. On the other hand, the prevalence based on the nested RT-PCR and RT-PCR results was 33.8% (34/102) and 20.6% (21/102), respectively. This result indicates that the RT-LAMP assay developed in this study is suitable for early field diagnosis of NNV with high sensitivity.

• The Plant Pathology Journal
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• v.36 no.3
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• pp.280-288
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• 2020

RNA interference (RNAi) has attracted attention as a promising approach to control plant viruses in their insect vectors. In the present study, to suppress replication of the rice stripe virus (RSV) in its vector, Laodelphax striatellus, using RNAi, dsRNAs against L. striatellus genes that are strongly upregulated upon RSV infection were delivered through a rice leaf-mediated method. RNAi-based silencing of peroxiredoxin, cathepsin B, and cytochrome P450 resulted in significant down regulation of the NS3 gene of RSV, achieving a transcriptional reduction greater than 73.6% at a concentration of 100 ng/μl and, possibly compromising viral replication. L. striatellus genes might play crucial roles in the transmission of RSV; transcriptional silencing of these genes could suppress viral replication in L. striatellus. These results suggest effective RNAi-based approaches for controlling RSV and provide insight into RSV-L. striatellus interactions.

• Korean Journal of Veterinary Service
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• v.42 no.2
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• pp.73-83
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• 2019

Foot-and-Mouth Disease (FMD) is a highly contagious trans-boundary viral disease caused by FMD virus, which causes huge economic losses. FMDV infects cloven hoofed (two-toed) mammals such as cattle, sheep, goats, pigs and various wildlife species. To control the FMDV, it is necessary to understand the life cycle and the pathogenesis of FMDV in host. Especially, the protein-protein interaction between FMDV and host will help to understand the survival cycle of viruses in host cell and establish new therapeutic strategies. However, the computational approach for protein-protein interaction between FMDV and pig hosts have not been applied to studies of the onset mechanism of FMDV. In the present work, we have performed the prediction of the pig's proteins which interact with FMDV based on RNA-Seq data, protein sequence, and structure information. After identifying the virus-host interaction, we looked for meaningful pathways and anticipated changes in the host caused by infection with FMDV. A total of 78 proteins of pig were predicted as interacting with FMDV. The 156 interactions include 94 interactions predicted by sequence-based method and the 62 interactions predicted by structure-based method using domain information. The protein interaction network contained integrin as well as STYK1, VTCN1, IDO1, CDH3, SLA-DQB1, FER, and FGFR2 which were related to the up-regulation of inflammation and the down-regulation of cell adhesion and host defense systems such as macrophage and leukocytes. These results provide clues to the knowledge and mechanism of how FMDV affects the host cell.

• Journal of Apiculture
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• v.32 no.4
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• pp.281-293
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• 2017

Sacbrood virus (SBV) is one of the main pathogenic RNA viruses of honeybee. SBV is found worldwide and many local strains have been reported, such as kSBV, cSBV, and wSBV. In this study, SBV-specific DNA fragments were cloned and sequenced by reverse-transcription PCR from 4 populations of A. mellifera, 4 sequences from 1 population belonged to the 2134D51 genotype (349 nucleotides, nt) and 12 sequences from 3 populations belonged to the 2100D0 genotype (400 nt) among the 16 determined sequences. A total of 87 points of mismatches were found by comparison with the most similar sequences in GenBank. Seventeen single-nucleotide polymorphisms (SNP) were detected, and 6 SNP-patterns in the 2100D0 genotype and 2 SNP-patterns in the 2134D51 genotype were identified based on SNP positions. In SNP-pattern 2, 10 SNPs were detected, but only 2 SNPs were found in SNP-pattern7. Meanwhile, one SNP-pattern was found from one RNA-sample, multi SNP-patterns were detected from other RNA-samples. Large numbers of SNP variants indicate that vast numbers of point-mutations on SBV have occurred since SBV invaded Korea and that SNP smay have been introduced individually over time. Thorough analysis of SNP variants will not only define the local infection-route, but also the relationships between SNP-pattern and SBV-pathogenic abilities.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2004.10a
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• pp.46-46
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• 2004

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• Archives of Pharmacal Research
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• v.15 no.4
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• pp.343-346
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• 1992

The synthesis of 6-aza-3', 5'-p-nitrophenylphosphoryltrioxy-2'-azido-2'-deoxy-2', 3' secouridine and 6-aza-3', 5'-phosphoryltrioxy-2'-azido-2'-deoxy-2', 3'-secouridine ammonium salt are described and they were evaluated for antiviral activity primarily against DNA and RNA viruses and found to be inactive, but no significant cytocidal effect was observed against Vero and Hela cell.