• Korean Journal Plant Pathology
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• v.14 no.5
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• pp.507-512
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• 1998

Molecular analysis has been done for characterization of the interactions between three beet curly top virus (BCTV) strains and two Arabidopsis ecotypes in terms of virus inducible disease symptoms and infectivities. The total DNA was isolated from three tissues (shoot tips, infection origins and roots) of virus infected plants and this DNA was analyzed by quantitatively and qualitatively to elucidate virus movement and symptom development. CTV-Worland infected Col-O and Sei-O showed only symptom shown in hypersusceptible ecotype Sei-O by BCTV-worland was shoot tip stunting. Kinetics of virus DNA accumulation of three different viruses indicated that roots contained more virus DNA than shoot tips or infection origins, and that disease symptom severity was strongly correlated with virus DNA accumulation. These results suggest that the mild and Worland-specific symptoms shown in Sei-O by BCTV-worland are caused by the interactions of host factors provided by hypersusceptible ecotype and viral factors of mild strain.

• Korean Journal of Veterinary Research
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• v.57 no.4
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• pp.249-252
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• 2017

Rabies virus (RABV) causes a neurological disease in warm-blooded animals that is nearly always fatal. In this study, we analyzed the matrix (M) genes in 10 Korean street RABV strains isolated from two Provinces during 2011-2013. The M genes in these 10 Korean strains were highly conserved during 1999-2013. Phylogenetic analysis revealed they were closely related to the M genes of RABVs isolated in northeastern China. Specific amino acid substitutions were identified in the KRVB1206, KRVF1301, and BV9901PJ strains. However, functional domains, including those involved in virus production and pathogenicity, were conserved in all 10 strains.

• Journal of Plant Biology
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• v.3 no.1
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• pp.32-38
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• 1960

Since the peculiar virus disease of chinese date tree (Zizyphus jujuba Mill. var. inermis Rehd.) has been noted in South Korea around 1950, 70% to 80% of the economically important trees have been either completely destroyed or infected with the virus, severe damage has been noted, particularly, across the area ranged from middle east to the middle part of Korea, including Seoul area. Yoon-Koock-Byung in 1958 first reported the disease and descirbed it might be caused by a kinds of yellows. But he did not conform in his paper that the disease is pecisely caused by yellows virus. The authors, hereby intend to identify the true cause of the desease of the chinese data tree by studying the external symptoms of the disease and the internal morphological characteristics of the diseaset plant which shows various abnormalities in contrast to the healthy checks. In view of fact that leaves of the infected plants become yellowish in color similar to the peach yellows, aster yellows, it is likely to be identifiable as the common yellows. Furthermore, the abnormal characteristics observed by the authors are as follow: The floral organs such as petals, sepals, stamens, and pistil turn into vegetative leaves, the leaves on heavily infected plant appear as small sized one and also showing as a common witch's broom like symptom. There are also an occuring of numerous advantitious shoots developed from both of stems and roots. The amount of photosynthetic starch grains increases in parenchymatous cells, necrosis takes place in mesophyll, Particularly, Palisade Parenchyma in the leaves of infected plants are distinguished in contrast to the healthy checks. From the symptoms and the present experimetns described above, the authors are believed that the disease of chinese data tree is not caused by the yellows. It appears the disease is rather similar to the symptoms of sandal spike virus which was noted in India early in this centry. But the host plant of standal disease, Santalum albun L. and the insect vector, Jassus indicus Wal., have never been reported in Korean flora and the founa. The termperature and the otehr environmental factors is quite different Korea and India. Thus the authors believe that the peculiar disease must be an endemic new virus origin in Korea and must be called as "shoot cluster disease of chinese date tree."

• Korean Journal of Veterinary Research
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• v.55 no.4
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• pp.227-232
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• 2015

Akabane and bovine ephemeral fever (BEF) viruses cause vector-borne diseases. In this study, inactivated Akabane virus (AKAV)+Bovine ephemeral fever virus (BEFV) vaccines with or without recombinant vibrio flagellin (revibFlaB) protein were expressed in a baculovirus expression system to measure their safety and immunogenicity. Blood was collected from mice, guinea pigs, sows, and cattle that had been inoculated with the vaccine twice. Inactivated AKAV+BEFV vaccine induced high virus neutralizing antibody (VNA) titer against AKAV and BEFV in mice and guinea pigs. VNA titers against AKAV were higher in mice and guinea pigs immunized with the inactivated AKAV+BEFV vaccine than in animals inoculated with vaccine containing revibFlaB protein. Inactivated AKAV+BEFV vaccine elicited slightly higher VNA titers against AKAV and BEFV than the live AKAV and live BEFV vaccines in mice and guinea pigs. In addition, the inactivated AKAV+BEFV vaccine was safe, and induced high VNA titers, ranging from 1 : 64 to 1 : 512, against both AKAV and BEFV in sows and cattle. Moreover, there were no side effects observed in any treated animals. These results indicate that the inactivated AKAV+BEFV vaccine could be used in cattle with high immunogenicity and good safety.

• Korean Journal of Veterinary Research
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• v.57 no.1
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• pp.37-42
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• 2017

Getah virus (GETV) infection causes sporadic outbreaks of mild febrile illness in horses and reproductive failure in pigs. In this study, we established a reverse transcription polymerase chain reaction (RT-PCR) method to detect GETV from suspected virus-infected samples. The reaction conditions were optimized and validated by using RNA extracted from GETV propagated in cell culture. A GETV-specific GED4 primer set was designed and used to amplify a 177 bp DNA fragment from a highly conserved region of the E1 glycoprotein gene in the GETV genome. RT-PCR performed with this primer set revealed high sensitivity and specificity. In the sensitivity test, the GED4 primer set detected GETV RNA at the level of $10^{2.0}\;TCID_{50}/mL$. In the specificity test, the GED4 primer set amplified only a single band of PCR product on the GETV RNA template, without non-specific amplification, and exhibited no cross-reactivity with other viral RNAs. These results suggest that this newly established RT-PCR method is useful for accurate identification of GETV infection in animals.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 1997.06a
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• pp.5-21
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• 1997

Unique virus-like particles were associated with five eriophyid mite-borne plant diseases of unknown etiology; fig mosaic, redbud yellow ringspot, rose orsette, thistle mosaic, and high plains disease of corn and wheat. Quasi-spherical, double membrane-bound particles (DMPs), 120 - 200 nm in diameter, were observed in the cytoplasm of all cell types in symptomatic leaves of infected plants. No DMPs were observed in symptomless plants. The DMPs in symptomatic thistles were associated with two types of inclusions, electron-dense amorphous material and tubular aggregates. Similar amorphous inclusions were also found in corn and wheat with high plains disease, while tubular inclusions were observed in figs with mosaic symptoms. The particles and inclusions were similar in some aspects to immature particles associated with viroplasms of animal and insect poxviruses and also to the double-enveloped particles of tomato spotted wilt virus associated with viroplasms during early stages of infection, but were unique and unlike any known plant viruses. The DMPs and associated viroplasm-like inclusions in the high plains disease were specifically immunogold labeled in situ with the disease-specific antiserum. Thread-like structures, similar to tenuivirus particles, present in the partially purified virus preparations were also immunogold labeled with the antiserum. It is suggested that the thread-like structures are derived from the DMP. In many cells of symptomatic corn and wheat samples, DMPs occurred together with flexuous rod-shaped particles and cylindrical inclusions of wheat streak mosaic potyvirus (WSMV), suggesting that the disease is caused by a mixed infection of WSMV and the agent represented by the DMPs. Based on cytopathology, symptomatology and mite and/or graft-transmissibility, the five diseases described in this paper are potentially caused by virus(es) and the DMPs associated with these diseases may represent virus particles. If the DMPs are indeed viral in nature, they would comprise a new group of plant viruses.

• Korean Journal of Poultry Science
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• v.39 no.2
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• pp.113-120
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• 2012

Newcastle disease virus (NDV) Kr005/V strain was generated through 55 serial passages of NDV Kr005 strain in Vero cells. The Kr005/V virus yielded high infective titers of $10^{7.8}$ $TCID_{50}/mL$ in Vero cells and the infected cells showed cytopathic effects such as marked cell rounding, though less frequent syncytia. The Kr005/V virus was heat-stable and classified into the lentogenic type with a Mean Death Time (MDT) of 120h or greater while the Kr005 strain was heat-labile and velogenic (MDT of 49.6 h). Only the single amino acid substitution (T to S) was observed at position 433 of the HN protein of the Kr005/V strain, whereas no amino acid change was found in the F protein. The Kr005/V input virus correlated well (correlation coefficient $r^2$=0.97) with the Kr005 virus when ten field sera were tested by virus neutralization test. The biological properties and usefulness of Vero cell-adapted Kr005/V virus were discussed.

• Korean Journal of Veterinary Research
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• v.63 no.1
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• pp.5.1-5.9
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• 2023

Feline panleukopenia virus (FPV), feline calicivirus (FCV), and feline herpesvirus type-1 (FHV-1) are major infectious pathogens in cats. We evaluated the immunogenicity of a new vaccine containing inactivated FPV, two FCVs, and FHV-1 in animals. An FPV, two FCVs, and an FHV-1 isolate were continuously passaged 70, 50, 80, and 100 times in CRFK cells. FP70, FC50, FC80, and FH100 were propagated and used as vaccine antigens. Two inactivated feline virus vaccines, feline rehydragel-adjuvanted vaccine (FRAV) and feline cabopol-adjuvanted vaccine (FCAV) were prepared and inoculated into mice and guinea pigs. Humoral immune responses were measured using hemagglutination inhibition (HI) for FPV and virus-neutralizing antibody (VNA) for two FCVs and FHV-1 tests. Serial passages in CRFK cells resulted in increase in titers of FPV and two FCVs but not FHV-1 The FCAV induced higher mean HI and VNA titers than the FRAV in guinea pigs; therefore, the FCAV was selected. Cats inoculated with FCAV developed a mean HI titer of 259.9 against FPV, and VNA titers of 64, 256, and 3.2 against FCV17D03, FCV17D283, and FHV191071, respectively. Therefore, cats inoculated with the FCAV showed a considerable immune response after receiving a booster vaccination.

• Korean Journal of Veterinary Service
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• v.38 no.2
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• pp.141-144
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• 2015

An equine herpesvirus-4 (EHV-4) was isolated in nasal swabs collected in a horse showing respiratory clinical signs. Equine dermis cells inoculated with the sample were observed with characteristic viral cytopathic effects after 3 days of postinoculation and the infected cells exhibited bright intracelluar fluorescence by indirect immunofluorescence assay. At the nucleotide level, the partial glycoprotein B gene of the Korean EHV-4 isolate (K001) had 99.9% identity to 1942 strain (GenBank No. M26171). To author's knowledge, the report describes the first isolation and partial characterization of EHV-4 in Korea. The virus can be used for further study of EHV-4.

• Research in Plant Disease
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• v.13 no.1
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• pp.30-33
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• 2007

One hundred and eighty-six leaves of soybean cv. Seokryangputkong that showed mild mosaic symptoms were collected randomly and ELISA tests were conducted with those leaf samples to screen the presence of Cowpea mosaic virus (CPMV). Ninety-three out of 186 samples reacted positively to CPMV, but those samples did negatively to Soybean mosaic virus (SMV). At least, 55 leaf samples revealed higher values than that of positive control. The results strongly confirmed that CPMV occurred severely in soybean cv. Seokryangputkong. However, a question is raised on the primary reservoir and vector for transmission of this virus. Since the farmer changes seeds every year, seed transmission is excluded. The virus was also purified, the analysis of coat protein conformed the virus of cowpea mosaic virus and UV absorption pattern confirmed that the causal virus of mosaic disease in soybean putkong was cowpea mosaic virus.