• The Korean Journal of Pesticide Science
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• v.13 no.4
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• pp.298-308
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• 2009

A flexuous rod-shaped virus was isolated from Cucurbita pepo leaves showing as green mosaic and puckering symptoms at Anseong, Korea. Based on the biological analysis, electron microscopy, and reverse transcription-polymerase chain reaction (RT-PCR), the virus isolate was identified as Papaya ringspot virus type watermelon (PRSV-W). From biological analysis, the host range of PRSV-W was limited to the families Cucurbitaceae and Chenopodiaceae. Most susceptible cucurbit species, such as Cucumis lanatus, Cucumis sativus, Cucurbita pepo, and Citrullus lanatus, showed symptoms of green mosaic, malformation, puckering, and narrow laminae by infection with PRSV-W. The local lesion were showed on the inoculated leaves of both Chenopodium amaranticolor and C. quinoa. Field survey of PRSV, Watermelon mosaic virus (WMV) and Zucchini yellow mosaic virus (ZYMV), three major viruses infecting cucurbit, was done during 2001 to 2003 on 173 commercial cucurbit cultivating fields distributed over the three regions of Gyeonggi, Gyeongbuk and Jeonnam Provinces where cucurbits are grown in different environmental conditions and cropping patterns. Typical viral symptoms were observed from 107 cultivating fields, and all three kinds of potyviruses were detected from 206 samples out of the 235 samples using RT-PCR. Watermelon mosaic virus (WMV) and Zucchini yellow mosaic virus (ZYMV) are the most widely distributed viruses in outdoor and retarding-culture fields, at an infection rating of 48 and 33 percents, respectively. PRSV was detected from 12 percent of 235 samples. The nucleotide and amino acid sequences of coat proteins (CP) of eight PRSV isolates, collected from several areas including Anseong, were determined and sequenced heterogeneity among the isolates was performed. The CP gene of PRSV showed 88.6~97.3 percent homology in nucleotide sequences and 95.1~99.3 percent homology in amino acid sequences with other PRSV isolates worldwide. The phylogenetic analysis indicated that the Korean PRSV isolates belong to the southern-east Asian cluster.

• Research in Plant Disease
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• v.12 no.2
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• pp.139-143
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• 2006

Virion captured reverse transcription polymerase chain reaction (VC/RT-PCR) could detect plant virus quickly and accurately. In the VC/RT-PCR, no antibody is needed unlike immuno-captured RT-PCR (IC/RT-PCR) which had been improved method of RT-PCR for plant viruses, and virus nucleic acids can be obtained easily within 30minutes by property of polypropylene PCR tube which is hold and immobilized viral particles on its surface. For the virion capture of Tomato spotted wilt virus (TSWV), the extraction buffer was tested. The optimum macerating buffer for TSWV was 0.01M potassium phosphate buffer, pH 7.0, containing 0.5% sodium sulfite. The viral crude sap was incubated for 30 min at $4^{\circ}C$. The virions in the PCR tubes were washed two times with 0.01M PBS containing 0.05% Tween-20. The washed virions were treated at $95^{\circ}C$ immediately for 1 min containing RNase free water and chilled quickly in the ice. Disclosed virions' RNAs by heat treatment were used for RT-PCR. Dilution end point of $10^{-5}$ from plant's crude sap infected with TSWV showed relatively higher detection sensitivity for VC/RT-PCR. During multiple detection using two or more primers, interference was arisen by interactions between primer-primer and plant species. The result of multiplex RT-PCR was influenced by combinations of primers and the kind of plant, and the optimum extraction buffer for the multiplex detection by VC/RT-PCR should be developed.

• Journal of Life Science
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• v.19 no.2
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• pp.284-288
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• 2009

The innate immune system is important for the first line of host defence against infectious agents, which have penetrated the mechanical barriers. Mannose-binding lectin (MBL or mannan-binding protein, MBP) is a serum protein that is synthesized in the liver as a part of the acute phase response. MBL binds to carbohydrate structures presented by a wide range of pathogenic bacteria, viruses, fungi, and parasites. MBL is synthesized as a monomer that has a carboxy-terminal carbohydrate recognition domain, a neck region and a collagen region. Low MBL level was reported to be the most frequent immuno-deficiency syndrome. Although extensive studies have yielded detailed information on the structure of MBL, functions of the MBL complex are not fully understood yet. We, here, present cloning process of MBL cDNA from the rat liver and production of truncated recombinant MBL protein using a bacterial expression system in order to produce anti-MBL polyclonal antibody. Anti-MBL polyclonal antibody was raised in a New Zealand rabbit and its affinity was tested against recombinant protein using western blot technique. MBL cDNA, recombinant protein and anti-MBL antibody could be used as great arsenals to dissect cellular biochemistry of MBL.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.05a
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• pp.584-587
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• 2018

Many viruses including mouse hepatitis virus, corona, measles, and sidbis viruses are known as causative virus of inducing demyelination which means destruction of myelination in nervous system of mice. The purpose of this study is to investigate processing of myelination by co-culture of Schwann cells and neuronal cells and demyelination induced by infection of sindbis virusin rat. Schwann cells and neuronal cells from dorsal root ganglion (DRG) in embryos (E16) of rat were cultured in vitro respectively. The purified neuronal cells with anti-mitotic agents and purified Schwann cells were co-cultured. After that, infection of sindbis virus into this myelinated co-culture system was performed. Myelination and demyelination process were observed using antibody of myelin basic protein meaning presence of myelination.We identified myelination and demyelination processing using antibody of peripheral myelin protein 22 (PMP 22) meaning presence of myelinated neuron. This study was supported by the Basic Research Program through the National Research Foundation (NRF) funded by the Ministry of Science, ICT & Future Planning (NRF-2015R1C1A1A01053484 and 2017R1A2B3005753).

• Research in Plant Disease
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• v.26 no.2
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• pp.103-108
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• 2020

Evaluations were made for the effects of cheese whey treatment on infection of pepper plants by cucumber mosaic virus-Vch (CMV-Vch) and pepper mottle virus-Kr (PepMoV-Kr). In a greenhouse, pepper plants sprayed with whey, prior to inoculation by CMV-Vch using aphids, showed a viral infection rate significantly lower (6.6%) than for the control (23.3%). In an open field experiment, in which CMV infection relied on natural transmission by aphids, pepper plants were sprayed with undiluted whey once a week, starting on the transplanting date (May 2) to the end of June. On June 5, these whey-sprayed plants showed a CMV infection rate reduced by 18.9% and 16.7%, compared to untreated and pesticide-treated plants, respectively. In the greenhouse, pepper plants inoculated with PepMoV-Kr mixed with whey showed a viral infection rate decreased by 60% compared to the control. The accumulated amount of PepMoV-Kr coat protein was less than that for the virus-only control at 6 days post inoculation (dpi), but increased up to a similar level as the control at 9 dpi. This study showed that cheese whey is effective in reducing infection of both CMV and PepMoV in pepper plants.

• Korean Journal of Clinical Laboratory Science
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• v.54 no.2
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• pp.103-109
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• 2022

In December 2019, the coronavirus disease 2019 (COVID-19) caused by the virus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in China and spread rapidly around the world, infecting millions of people. Cases of COVID-19 infection were observed to lead to viral pneumonia. Thirty-five patients admitted to the Gyeonggi Medical Center, South Korea, between November 2020 to January 2021, were found to have been infected with the influenza virus A and B, which cause symptoms similar to COVID-19. The records of these patients and those of COVID-19 patients who visited the hospital for medical examination were compared. The study patients included thirty patients with COVID-19 and/or influenza, five of those with influenza alone. A group of 121 patients without infection was used as control. Patients with COVID-19 and influenza had significantly higher lactate dehydrogenase levels than the patients with COVID-19 alone. The erythrocyte sedimentation rate (ESR) was higher in patients with COVID-19 alone than in other groups. Significant clinical outliers were observed in the COVID-19 and influenza infection group compared with the COVID-19 alone group. These results are expected to play an important role in the analysis of the hematological data of infected patients and the comparison of simultaneous and single infection data to determine clinical symptoms and other signs. These results may also assist in the development of vaccines and treatments for COVID-19.

• Korean journal of applied entomology
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• v.63 no.1
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• pp.43-51
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• 2024

Thrips infest hot peppers (Capsicum annuum) cultivating in open fields and give serious economic damages. This study reports their yearly occurrence from transplanting to harvest at three different places in Andong, an intense hot pepper-cultivating area. Two main occurrence peaks were detected in June and September. Two dominant thrips were the flower flowers, Frankliniella occidentalis and F. intonsa, which comprised of over 87% of the total occurring thrips. Other thrips did not follow the occurrence peaks of the two dominant species. Tomato spotted wilt virus (TSWV) was detected from the dominant two species, in which higher viruliferous rate was recorded in F. intonsa. Although the hot peppers were the resistant varieties against TSWV, some of them cultivating in the fields exhibited a characteristic disease symptom infected by the virus over the growing seasons. TSWV was isolated from the viruliferous thrips and assessed in NSs sequences encoded in S RNA segment of the virus. Compared to the known resistance breaking (RB) strains, the TSWV isolated from the viruliferous thrips in Andong did not show any RB mutations.

• The Korean Journal of Zoology
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• v.22 no.4
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• pp.141-152
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• 1979

Feline leukemia virus DNA polymerase was purified by ion-exchange and nucleic acid affinity chromatographies. The enzyme consists of a single polypeptide chain of approximately 72, 000 molecular weight as determined by both of a glycerol density gradient centrifugation and SDS-polyacrylamide gel electrophoresis. The preferred divalent cation for DNA synthesis is $Mn^2+$ on a variety of template-primers, and its optimum concentration appears to be significantly lower than reported results of other mammalian type-C viral enzymes. The divalent cation requirement for maximum activity of RNase H is similar to those of DNA polymerase. Both DNA polymerase and RNase H activities appear to reside on the same molecule as demonstrated by the copurification of both activities through various purification steps. An additional RNase H without detectible polymerase activity was generated by a limited chymotrypsin digestion. This RNase H activity was inhibited equally effectively as RNase H in the intact reverse transcriptase by antisera prepared against reverse transcriptase of feline leukemia virus. Neutralization and binding test showed that antibody binding to reverse transcriptase molecule did not completely inhibit the polymerase activity.

• Journal of Sericultural and Entomological Science
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• v.37 no.1
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• pp.46-51
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• 1995

In order to develope baculovirus expression vector system, we constructed new transfer vector of nuclear polyhedrosis virus of the silkworm, Bombyx mori. The promoter region containing only adenine of translation start codon of polyhedrin gene was cloned by polymerase chain reaction technique. And the 5' and 3' leader regions of polyhedrin gene was sequentially cloned. The polyhedrin coding gene was deleted from the ＋2 to the ＋597 position. As the result, we constructed new transfer vector which has EcoRI, SacI and KpnI sites for the cloning sites of foreign gene. New transfer vector was named as pBmKSKl. Escherichia coli $\beta$-galactosidase gene as foreign gene was inserted into pBmKSKl, under the control of the polyhedrin promoter and expressed in B. mori cells. The result showed that the new transfer vector pBmKSK1 is functional.

• Research in Plant Disease
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• v.23 no.4
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• pp.379-382
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• 2017

In March 2016, an isolate of Cucumber mosaic virus (named Gyp-CMV) was isolated from the Sambungai (Gynura procumbens) showing the symptoms of mosaic and chlorosis. The isolate Gyp-CMV was characterized by disease reactions in several indicator plants, reverse transcription-polymerase chain reaction (RT-PCR), PCR-restriction fragment length polymorphism, and sequence analysis of movement protein (3a) and coat protein (CP) genes. Tobacco, tomato, pepper, ground cherry, and lambsquarters (Chenopodium quinoa and C. amaranticolor) appeared typical CMV symptoms, but zucchini and cucumber were not infected. Phylogenetic analysis of the 3a and CP gene indicated that Gyp-CMV belongs to the CMV subgroup II. Sequence identities of the Gyp-CMV 3a and CP genes showed 99.3% and 100% to that of Hnt-CMV at amino acid level. To our knowledge, this is the first report of CMV infection in Gynura procumbens.