• Journal of Microbiology
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• 제45권3호
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• pp.187-192
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• 2007

REOviruses (Respiratory Enteric Orphan viruses) are ubiquitous, non-enveloped viruses containing 10 segments of double-stranded RNA (dsRNA) as their genome. They are common isolates of the respiratory and gastrointestinal tract of humans but are not associated with severe disease and are therefore considered relatively benign. An intriguing characteristic of reovirus is its innate oncolytic potential, which is linked to the transformed state of the cell. When immortalized cells are transfected in vitro with activated oncogenes such as Ras, Sos, v-erbB, or c-myc, they became susceptible to reovirus infection and subsequent cellular lysis, indicating that oncogene signaling pathways are exploited by reovirus. This observation has led to the use of the virus in clinical trials as an anti-cancer agent against oncogenic tumors. In addition to the exploitation of oncogene signaling, reovirus may further utilize host immune responses to enhance its antitumor activity in vivo due to its innate interferon induction ability. Reovirus is, however, not entirely benign to immunocompromised animal models. Reovirus causes so-called "black feet syndrome" in immunodeficient mice and can also harm neonatal animals. Because cancer patients often undergo immunosuppression due to heavy chemo/radiation-treatments or advanced tumor progression, this pathogenic response may be a hurdle in virus-based anticancer therapies. However, a genetically attenuated reovirus variant derived from persistent reovirus infection of cells in vitro is able to exert potent anti-tumor activity with significantly reduced viral pathogenesis in immunocompromised animals. Importantly, in this instance the attenuated, reovirus maintains its oncolytic potential while significantly reducing viral pathogenesis in vivo.

• 한국버섯학회지
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• 제5권1호
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• pp.39-42
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• 2007

색소변이체에서 버섯 바이러스의 게놈인 dsRNA가 확인되었으며, 크기는 각각 5.8kb, 1.8kb 이었다. 느타리바이러스 진단용 프라이머인 PVP로 RT-PCR을 수행한 결과 500bp 크기의 특이밴드가 관찰되었다. 또한 양송이 바이러스 진단용 프라이머 LIVP와 MBVP에서도 특이밴드가 관찰되었으나 양송이 바이러스와는 다른 양상이었다. 원형느타리의 백색변이체 (MGL2205)에 존재하는 바이러스유사입자는 구형이었으며, 크기는 14, 20~45nm이었다. 균사체의 세포단면을 관찰한 결과 바이러스 순화액에서 확인된 바이러스유사입자와 비슷한 구형의 입자들이 관찰되었으며, 순화된 바이러스와 동일한 입자인지는 추후 확인되어야 할 것으로 사료된다. 원형느타리 백색변이체(MGL2205)에 존재하는 바이러스의 최적 증식 조건은 $15^{\circ}C$, pH 6, 배양기간 3주인 것으로 판단되며, 이 결과는 이와 유사한 재배적 조건에서 재확인되어야 할 것으로 사료된다.

• IMMUNE NETWORK
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• 제11권3호
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• pp.155-162
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• 2011

Background: Toll-like receptor 3 (TLR3) recognizes double-stranded RNA (dsRNA) and induces inflammation. In this study we attempted to ascertain if there are endogenous host molecules controlling the production of cytokines and chemokines. Two candidates, ribosomal protein L19 and L22, were analyzed to determine if they influence cytokine production followed by TLR3 activation. In this study we report that L19 acts upon production of IP-10 or IL-8 differently in glioblastoma cells. Methods: L19 or L22 was transfected into HEK293-TLR3, A549 or A172 cells. After treatment with several inhibitors of NF-${\kappa}B$, PI3K, p38 or ERK, production of IL-8 or IP-10 was measured by ELISA. siRNA was introduced to suppress expression of L19. After Vesicular stomatitis virus infection, viral multiplication was measured by western blot. Results: L19 increased ERK activation to produce IL-8. In A172 cells, in which TLR3 is expressed at endosomes, L19 inhibited interferon regulatory factor 3 (IRF3) activation and IP-10 production to facilitate viral multiplication, whereas L19 inhibited viral multiplication in A549 cells bearing TLR3 on their cell membrane. Conclusion: Our results suggest that L19 regulates TLR3 signaling, which is cell type specific and may be involved in pathogenesis of autoimmune diseases and chronic inflammatory diseases.

• The Plant Pathology Journal
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• 제16권5호
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• pp.269-279
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• 2000

Alfalfa mosaic alfamoviruses(AIMV) were isolated from infected potato (Solanum tuberosum) and azuki bean (Paseolus angularis) in Korea. Two AIMV isolated from potatoes were named as strain KR (AIMV-KR1 and KR2) and AIMV isolated from azuki bean was named as strain Az (AIMV-Az). Each isolated AIMV strain was characterized by using their host ranges, symptom developments, serological relations and nucleotide sequence analysis of coat protein (CP) gene. Strains KR1, KR2, and Az were readily transmitted to 20 of 22 inoculated plant species including bean, cowpea, tomato, tobacco, and potato. AIMV-KR1 and KR2 produced the typical symptoms like chlorotic or necrotic spots in Chenopodium quinoa and Solanum tuberosum cv. Superior. AIMV-Az caused bright yellow mosaic symptom and leaf malformation in Nicotiana glauca, which were different from the common mosaic symptom caused by AIMV-KR1 and KR2. Electron microscope observation of purified virus showed bacilliform virions containing a single-stranded plus-strand RNAs of 3.6, 2.6, 2.0 and 0.9 kbp in length, respectively, similar in size and appearance to those of Alfamovirus. In SDS-PAGE, the coat protein of the two viruses formed a consistent band that estimated to be about 24kDa. The CP genes of the AIMV strains, KR1, KR2, and Az have been amplified by RT-PCR using the specific primers designed to amplify CP gene from viral RNA-3, cloned and sequenced. Computer aided analysis of the amplified cDNA fragment sequence revealed the presence of a single open reading frame capable of encoding 221 amino acids. The nucleotide and peptide sequence of viral CP gene showed that strain KR1, KR2, and Az shared highest nucleotide sequence identities with AIMV strain 425-M at 97.7%, 98.2%, and 97.2%, respectively. CP gene sequences of two strains were almost identical compared with each other. Altogether, physical, serological, biological and molecular properties of the purified virus.

• The Plant Pathology Journal
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• 제19권1호
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• pp.30-33
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• 2003

The chestnut blight fungus, Cryphonectria parasitica, and its hypovirus aye a useful model system in the study of the mechanisms of hypoviral infection and its consequences, such as a biological control of fungal pathogens. Strains containing the double-stranded (ds) RNA viruses Cryphonectria hypovirus 1 show characteristic symptoms of hypovirulence and display hypovirulence-associated changes, such as reduced pigmentation, sporulation, laccase production, and oxalate accumulation. Interestingly, symptoms caused by hypoviral infection appear to be the result of aberrant expression of a number of specific genes in the hypovirulent strain. Several viral regulated fungal genes are identified as cutinase gene, Lac1, which encodes an extracellular laccase, Crp, which encodes an abundant tissue-specific cell-surface hydrophobin that mediates physical strength, and Mf2/1 and Mf2/2, which encode pheromone genes involved in poor sporulation in the presence of hypo-virus. Since the phenotypic changes in the fungal host are pleiotropic, although coordinated and specific, it has been suggested that the hypovirus disturbs one or several regulatory pathways (Nuss,1996). Accordingly, several studies have shown the implementation of a signal transduction pathway during viral symptom development. Although further studies are required, hypovirulence and its associated symptom development due to the hypoviral regulation of a fungal hetero-trimeric G-protein have been suggested. In addition, recent studies have shown the presence of a novel protein kinase gene cppk1 and its transcriptional upregulation by hypovirus. In this review, the presence of important components in signal transduction pathway, their putative biological function, and viral-specific regulation will be addressed.

• 식물병연구
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• 제12권3호
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• pp.213-220
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• 2006

2003년 청송지역 농가포장에서 심한 위축증상을 나타내는 콩 시료를 채집하였다. 이 시료를 RT-PCR로 진단한 결과 콩위축바이러스, Soybean dwarf virus(SbDV-L81)에 감염된 것으로 확인되었다. 본 연구는 우리나라에서 콩위축바이러스의 발생에 관한 최초 보고이다. 이 바이러스의 추가적인 특징을 알아보기 위하여 종 특이적 프라이머를 이용한 RT-PCR로 게놈의 부분 염기서열을 결정하였다. 결정된 염기서열은 병징 발현 유형과 매개충 특이성에 기초하여 이전에 조사된 SbDV 계통들과 비교분석하였다. ORF 2와 ORF 3 유전자사이 영역(intergenic region)과 ORF 2, ORF 3 및 ORF 4의 코팅영역에서 SbDV-L81은 황화계통(SbDV-YS and YP) 보다 위축계통(SbDV-DS and DP)과 유사한 특징을 보였다. 한편, ORF 5의 5'쪽 코딩영역은 완두수염진딧물(Acyrthosiphon pisum)이 매개충인 계통(SbDV-YP and DP)과 밀접한 관련이 있은 것으로 나타났다. SbDV-L81은 자연상태에서의 병정과 5가지 영역의 염기서열 비교결과에서 SbDV-DP 계통과 밀접한 관련이 있는 것으로 생각된다.

• Journal of Applied Biological Chemistry
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• 제59권1호
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• pp.31-36
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• 2016

이산화염소는 높은 항생효과로 살균제로 사용되고 있고, 저곡해충을 대상으로 살충 효과도 보이고 있다. 본 연구는 이 이산화염소의 유용 효과를 넓히기 위해 이 물질이 항암 및 항바이러스 활성을 나타낼 수 있는 지를 검증하였다. 인체에 나타나는 5종의 암 세포주에 대해서 이산화염소의 세포독성을 분석하였다. 유방암 2종 세포주(MCF-7, MDA-MB-231)와 대장암 3종 세포주(LoVo, HCT-116, SW-480) 모두에 대해서 이산화염소는 높은 세포 독성을 나타냈다. 이러한 세포독성은 이산화염소의 활성산소 유발 효과에 기인된다. 이산화염소가 처리된 암세포주는 모두 세포내 높은 활성산소를 형성하였다. 이는 대조구로서 일반 곤충 세포주와 비교하여 훨씬 높은 활성산소를 지녔다. 반면에 항산화제인 비타민 E를 처리하면 이러한 세포독성이 크게 줄어 암 세포에 대해 높은 세포독성은 활성산소에 의해 기인되었다는 것을 입증하였다. 또한 이산화염소는 서로 다른 바이러스에 대해서 항바이러스 활성을 나타냈다. 곤충병원성 바이러스이고 이중 가닥의 DNA 게놈을 지닌 벡큘로바이러스의 일종인 Autographa californica nuclear polyhedrosis virus (AcNPV)는 이산화염소 노출에 따라 활성을 잃어 핵다각체 형성 능력이 크게 둔화되었다. AcNPV에 대한 이산화염소의 항바이러스 효과는 반응 시간에 비례하여 증가했다. 식물병원성 바이러스이고 단일가닥의 RNA 게놈을 지닌 담배모자이크바이러스는 이산화염소 노출에 따라 바이러스 함량이 줄었고, 담배에 대한 병원력도 낮아졌다. 따라서 본 연구는 이산화염소가 항암 및 항바이러스 활성을 지니며, 이는 이 물질에 의한 높은 활성산소 유발에 기인된 것으로 판명되었다.

• Molecules and Cells
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• 제26권5호
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• pp.496-502
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• 2008

Cryparin, encoded as a single copy gene (Crp) of the chestnut blight fungus Cryphonectria parasitica, is the most abundant protein produced by this fungus. However, its accumulation is decreased remarkably in C. parastica strains containing the double-stranded (ds) RNA virus Cryphonectria hypovirus 1. To characterize the transcriptional regulatory element(s) for strong expression and viral regulation, promoter analysis was conducted. Serial deletion of the Crp promoter region resulted in a step-wise decrease in promoter activity, indicating a localized distribution of genetic elements in the cryparin promoter. Promoter analysis indicated two positive and a repressive cis-acting elements. Among them, the promoter region between nt -1,282 and -907 appeared to be necessary for hypoviral-mediated down-regulation. An electrophoretic mobility shift assay (EMSA) on the corresponding promoter region (-1,282/-907) indicated two regions at (-1,257/-1,158) and (-1,107/-1,008) with the characteristic AGGAGGA-N42-GAGAGGA and its inverted repeat TCCTCTC-N54-TCCTCCT, respectively, appeared to be specific binding sites for cellular factors.