• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.65.1-65
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• 2003

In addition to the five well-characterized genes of Tobacco mosaic virus (TMV), this virus contains a sixth open reading frame (ORF6) that encodes a 4.8 kDa protein. TMV ORF6 overlaps the ORFs encoding the 30 kDa movement protein and the adjacent 17.5 kDa capsid protein. Although the 4.8 kDa protein could not be detected in vivo, alteration of the AUG codons of this ORF resulted in a mutant virus that attenuated the virulence of the mutated TMV in Nicotiana benthamiana, but not N. tabacum (tobacco). These sequence changes did not affect either the replication or movement of the mutated TMV. Expression of TMV ORF6 from the virus expression vector Potato virus X (PVX) intensified the virulence of this virus in N. benthmiana, but not tobacco, while expression of TMV ORF6 from the virus expression vector Tobacco rattle virus enhanced the pathogenicity observed in both N. benthamima and tobacco. Thus, the TMV ORF6 is a host- and virus-specific. virulence factor. However, two separate assays indicated that the TMV 4.8 kDa protein was not a suppression of RNA silencing. A fusion protein formed between the TMV 4.8 kDa protein and the green fluorescent protein was expressed from the PVX vector and localized to plasmodesmata. Possible roles of the 4.8 kDa protein in pathogenicity will be discussed

• Journal of Veterinary Science
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• 제22권4호
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• pp.42.1-42.16
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• 2021

Background: Inclusion body hepatitis (IBH) is an economically important viral disease primarily affecting broiler and breeder chickens. All 12 serotypes of fowl adenovirus (FAdV) can cause IBH. Objectives: To characterize FAdV isolates based on phylogenetic analysis, and to study the pathogenicity of FAdV-8b in specific-pathogen-free (SPF) chickens following virus inoculation via oral and intramuscular (IM) routes. Methods: Suspected organ samples were subjected to virus isolation and polymerase chain reaction (PCR) for FAdV detection. Hexon gene sequencing and phylogenetic analysis were performed on FAdV-positive samples for serotype identification. One FAdV-8b isolate, UPM/FAdV/420/2017, was selected for fiber gene characterization and pathogenicity study and was inoculated in SPF chickens via oral and IM routes. Results: The hexon gene phylogenetic analysis revealed that all isolates belonged to FAdV-8b. The fiber gene-based phylogenetic analysis of isolate UPM/FAdV/420/2017 supported the grouping of that isolate into FAdV species E. Pathogenicity study revealed that, chickens infected with UPM/FAdV/420/2017 via the IM route had higher clinical score values, higher percent mortality, higher degree of the liver lesions, higher antibody response (p < 0.05), and higher virus shedding amounts (p < 0.05) than those infected via the oral route. The highest virus copy numbers were detected in liver and gizzard. Conclusions: FAdV-8b is the dominant FAdV serotype in Malaysia, and pathogenicity study of the FAdV-8b isolate UPM/FAdV/420/2017 indicated its ability to induce IBH in young SPF chickens when infected via oral or IM routes.

• 한국잠사곤충학회지
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• 제17권2호
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• pp.101-118
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• 1975

가잠에 있어서 세포질 다각체 바이러스의 병원성 및 이형 바이러스 접종에 의한 유발 간섭현상을 구명하기 위하여 현장여품종인 잠103$\times$잠104의 원종과 교잡종에 있어서 육각형 및 사각형 세포질다각체 바이러스의 병원성 이형 세포질다각체 바이러스 접종에 의한 잠재성 바이러스의 활성화 및 활성화된 세포질다각체 바이러스와 접종한 세포질다각체 바이러스 사이의 간섭현상을 조사한 결과는 다음과 같다. 1. 세포질다각체 바이러스의 병원성 1) 가잠의 원종 (잠103, 잠104) 및 교잡종(잠103$\times$잠104)에 있어서 육각형 세포질다각체 바이러스의 병원성은 상호간에 고도의 유의성이 있어 교잡종이 가장 낮은 발병률을 보였고 일본종이 중간을 나타냈으며 중국종이 가장 높은 발병률을 보였다. 사각형 세포질다각체 바이러스에서도 유의성을 나타내어 있었으나 교잡종과 일본종이 같은 수준이고, 일본종과 중국종이 같은 수준이었으며, 교잡종과 중국종 사이에는 유의성이 있었다. 2) 접종령기에 따르는 병원성은 육각형 및 사각형 세포질다각체 바이러스가 다같이 고도의 유의성이 있었으며 2령기잠의 접종이 4령기잠이 접종보다 발병률이 높았다. 3) 접종된 병원체의 농도에 있어서 육각형 및 사각형 세포질다각체 바이러스의 병원성은 다같이 고도의 유의성이 있었으며, 농도가 높을수록 병원성이 높았다. 2. 이형 바이러스 접종에 의한 유발 및 간섭현상 1) 원종 및 교잡종에 있어서는 교잡종보다 원종에서 유발률이 높았으며 원종에서는 일본종보다 중국종에서 유발률이 높았다. 2) 접종 령기에 있어서는 2령기잠 접종이 4령기잠 접종보다 유발률이 높았다. 3) 사각형 세포질다각체 바이러스의 경구접종에 의한 육각형 세포질다각체 바이러스이 활성화 정도는 저농도에서 높았으며 고농도에서는 매우 낮았다. 4)육각형 세포질다각체 바이러스의 경구접종에 의한 사각형 세포질다각체 바이러스의 활성화 정도는 저농도에서는 매우 낮았으며 고농도에서는 전혀 나타나지 않았다. 5) 혼합감염은 2령기잠의 접종이 4령기잠의 접종보다 높았으며 4.2$\times$$10^{6}$/ml 농도에서 가장 높았다. 6)2령기잠에 사각형 세포질다각체 바이러스를 접종할 경우 저농도에서는 활성화한 육각형 세포질다각체 바이러스가 접종한 사각형 세포질다각체 바이러스가 활성화한 육각형 세포질다각체 바이러스를 간섭하는 것으로 생각된다. 또한 4.2$\times$$10^{6}$/ml 농도를 중심으로 개체 안에서의 육각형과 사각형 세포질다각체 바이러스 사이의 간섭현상이 평형상태를 이루는 것으로 생각된다.

• 한국어병학회지
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• 제25권2호
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• pp.117-121
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• 2012

The pathogenicity of viral hemorrhagic septicemia virus (VHSV) from olive flounder Paralichthys olivaceus was investigated with masu salmon Oncorhynchus masou fry. The cumulative mortality of fish challenged with FYeosu05 isolate at $10^{6.5}$ $TCID_{50}$/fish was 60%. No mortality was observed in fish challenged with the isolates at $10^{5.5}$ $TCID_{50}$/fish and in mock-challenged fish. The affected fish showed darkening of the body, expanded abdomen, pale gills and enlarged spleen. VHSV from $10^{6.3}$ to $10^{7.8}$ $TCID_{50}$/g-tissue was re-isolated from the dead fish. These results suggest that the VHSV from olive flounder is pathogenic to masu salmon fry, although with low virulence.

• 한국가금학회지
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• 제27권2호
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• pp.109-114
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• 2000

The objective of these experiments was to develop an attenuated thermostable Newcastle disease virus(NDV), CBP-1 strain isolated from infected pheasants. Safety, pathogenicity and protective effects against velogenic NDV were also investigated to evaluate if the attenuated NDV, CBP-1 strain could be a candidate for a new NDV vaccine strain. CBP-1 strain was passaged up to the 173 times by nine days old embryonated eggs and chicken embryo fibroblast(CEF) cell cultures. Its sensitivitly to lipid solvents and low pH, thermostability, mean death time(MDT), intracerebral pathogenicity index(ICPI) of one day old chicks and intravenous pathogenicity index(IVPI) of four weeks old chicks were examined. Safety, boosting and protective effects were tested by chicks mortality. CBP-1 NDV strain had significant thermostability at 56$\^{C}$ for 30 minutes. by hemagglutinin activity and egg infectivity test, but was not resistant to lipid solvent. It showed possibility to use as a feed or water vaccine because of the resistance to low pH. MDT, ICPI and IVPI of CBP-1 were attenuated from 51.5, 1.96, 2.60 to 112.4, 1.12, 1.45. These results implied that the 173rd passages in embryonated egg and CEF cell cultures induced a substantial attenuation of the pathogenicity of the parent virus, changing the virulence from velogenic to intermediate between mesogenic and lentogenic. After vaccination with CBP-1 at one day old by drinking water mortality was 17.5%. However, spray vaccination with B1 at one day old, CBP-1 at two weeks ild and challenge with velogenic Kyojeongwon strain at four weeks old showed 93.5% survival rate. Mortality of chicks, vaccination with 173rd passaged CBP-1 strain at one day old, two weeks old and challenge with Kyokeongwon strain at four weeks old, was 20.0%. The results of these studies indicated that partial attenuated CBP-1 strain tended to be a low safety for ND of broiler chicks and would need to be more successive attenuation.

• Journal of Microbiology and Biotechnology
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• 제30권9호
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• pp.1273-1281
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• 2020

Due to the broad host suitability of viral vectors and their high gene delivery capacity, many researchers are focusing on viral vector-mediated gene therapy. Among the retroviruses, foamy viruses have been considered potential gene therapy vectors because of their non-pathogenicity. To date, the prototype foamy virus is the only retrovirus that has a high-resolution structure of intasomes, nucleoprotein complexes formed by integrase, and viral DNA. The integration of viral DNA into the host chromosome is an essential step for viral vector development. This process is mediated by virally encoded integrase, which catalyzes unique chemical reactions. Additionally, recent studies on foamy virus integrase elucidated the catalytic functions of its three distinct domains and their effect on viral pathogenicity. This review focuses on recent advancements in biochemical, structural, and functional studies of foamy virus integrase for gene therapy vector research.

• International Journal of Industrial Entomology and Biomaterials
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• 제1권2호
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• pp.177-181
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• 2000

Spilarctia obliqua(Wlk.) is a serious pest of mulberry which is naturally affected by its nucleopolyhedrosis virus (SoNPV) in field conditions. The polyhedral occlusion bodies (POB's) were hexahedron under scanning and transmission electron microscope and measured 0.42${\mu}{\textrm}{m}$ to 0.67 ${\mu}{\textrm}{m}$ in diameter. The symptoms of NPV infected S. obliqua larvae resembled with that of other NPVs' infected lepidopterous larvae. The pathogenicity and potentiality of this virus against S. obliqua was tested in the laboratory conditions and the results showed 100% mortality in larvae inoculated with SoNPV at 6.23${\times}10^5$ POBs/ml. Therefore, SoNPV appears to have a high potential as a microbial biocontrol agent against S. obliqua larvae.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.149.1-149
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• 2003

A lily strain of Cucumber mosaic virus (LK-CMV) was not able to systemically infect zucchini squash (Cucurbita pepo), while Fny strain of CMV (Fny-CMV) caused systemic mosaic and stunting symptom at 4 days post-inoculation on the same host species. The pathogenicity of LK-CMV in zucchini squash was investigated by reassortments of genomic RNAs of LK-CMV and Fny-CMV for infection, as well as by pseudorecombinants generated from biologically active transcripts of CDNA clones of LK-CMV and Fny-CMV, respectively. The assessments of pathogenicity for LK-CMV indicated that RNA2 of LK-CMV was responsible for systemic infection in zucchini squash. In the protoplast of zucchini squash, the RNA accumulations of all constructed pseudorecombinants were indistinguishable and LK-CMV replication was slightly lower than that of Fny-CMV, suggesting that the inability of LK-CMV to infect squash plants was responsible for the poor efficiency of virus movement, rather than the reduction of replication function.

• 한국응용곤충학회지
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• 제29권3호
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• pp.184-189
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• 1990

담배거세미나방 핵다각체병 바이러스(Spodoptera litura nuclear polyhedroses virus: SINPV) 미생물살충제로 개발하기 위하여 기주식물, 온도 보관조건 및 태양광선에 의한 병원성 및 안정성에 대하여 조사하였다. 콩잎에 살포한 SlNPV의 담배거세미나방 3령과 5령 유충에 대한 $LC_{50}$은 각각 $1.301\times10^{4 PIBS}/ml$와 $1.087\times10^{5 PIBS}/ml$였으며 $1.0\times10^{6 PIBS}/ml$에 대한 $LC_{50}$은 3령과 5령에 대하여 각각 7.3일파 8.9일이었다. SINPV는 $60^{\circ}C$에서 4시간, $60^{\circ}C$에서 1 10분 처리하였을 때 활성이 저하되었으며 처리시간이 길어질수록 급격한 활성감소현상을 보였다. 또한 SINPV는 $-20^{\circ}C$ 동결보관이 $4^{\circ}C$나 $25^{\circ}C$ 보관보다 안정적인 활성을 유지하였다. 콩잎표변에 살포한 SINPV는 콩잎표변에 살포한 경우 3일 후에 불활화하였으나 콩잎 이면살포에서는 10일간 활성이 지속되었다.

• 대한수의학회지
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• 제30권1호
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• pp.65-71
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• 1990

Rabbits were experimentally infected with rabbit hemorrhagic disease virs and the viral pathogenicity, hemagglutinability, and the effect of physicochemical factors were studied. The experimental results were summariaed as follows: 1. Mean rectal temperature of 11 infected rabbits was $40.0{\pm}0.47^{\circ}C$ prior to the virus inoculation, and $39.9{\pm}0.75^{\circ}C$ after 12hrs., $40.2{\pm}0.65^{\circ}C$ after 24hrs., $40.1{\pm}0.77^{\circ}C$ after 36hurs, and $40.6{\pm}0.56^{\circ}C$ just before the death. 2. Mean death time of infected rabbits was $40.3{\pm}22.0$ honrs and its range was 24 to 93 hours. 3. O, B, AB and A type of human erythrocytes were shown their HA in the order, but rabbit and chicken erythrocytes were not hemagglutinated by the virus. 4. In the hemagglutination, less than 0.25 per cent of a final concentration of erythrocytes and 0.2 per cent of BSA in PBS resulted in the best hemagglutination. Phosphate concentration in a range of 0.01M to 0.10M in PBS was not influenced on the hemagglutination reaction, and its pH 7.0 resulted in a better HA. 5. The hemagglutinating titers, in log 2 scale, of organs and tissues of the virus infected rabbits were $9.3{\pm}3.8$ (liver), $9.1{\pm}3.9$ (blood), $6.2{\pm}2.6$ (spleen) and $5.0{\pm}2.5$ (kidney). 6. The physicochemical factors such as heating ($50^{\circ}C$, 10 min.), trypsin treatment (0.05 pre cent, 5 min.), acid treatment (pH 3.0, 20 min.) and ether extraction (3 times) were not affective to the stability of virus and viral HA activities.