• 한국잠사학회:학술대회논문집
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• 한국잠사학회 1997년도 Progress and Future Development of Sericultural Science and Technology 40th Anniversary Commemoration Symposium
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• pp.73-101
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• 1997

Baculoviruses are characterized by large double-stranded circular DNA genomes and rod-shaped enveloped virions. Bombyx mori nucleopolyhedrovirus(BmNPV) is a major pathogen, which causes severe damage in sericulture. Currently, BmNPV is recogtnized as an improtant tool in molecular biology, especially for expression of useful genes in B.mori cells and silkworm larvae. Our laboratories have focused on the studies of the molecular mechanisms of BmNPV replication and the application of BmNPV to agriculture and medicine. The entire nucleotide sequence of the BmNPV genome has recently determined. The BmNPV genome possessed 135 putative genes and 7 homologous repeated sequence (hrs) regions. Relatively little space, a few to a few hundred base-pairs, was observed between the open reading frames and hrs. Termination codons often overlapped. These results showed a compactly packde BmNPV genome. Based on comparative sequence analyses, we speculated that the ancestor of BmNPV was a baculovirus similar to Autographa californica NPV(AcNPV). The function of the BmNPV genes were characterized by gene deletion analysis; p35 was found to be involved in blocking apoptosis and cysteine proteinase was found to be involved in horizontal virus transmission by degrading viral-infected larval host. By AcNPV and BmNPV coinfection experiments, we identified a BmNPV gene involved in expanding host specificity of AcNPV. The identified gene was likely encoded a DNA helicase based on the amino acid sequence analysis; a few amino acid substitutions in the putative DNA helicase gene resulted in the expansion of host range of AcNPV. These findings indicate that BmNPV evolved within a short period from an AcNPV-like ancestral virus due to rapid evolution including specific amino acid substitutions and gene deletions/insertions.

• 한국미생물·생명공학회지
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• 제49권3호
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• pp.305-315
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• 2021

The cotton leafworm, Spodoptera littoralis, is a major pest in Egypt and many countries worldwide, and causes heavy economic losses. As a result, management measures to control the spread of the worm are required. S. littoralis nucleopolyhedrovirus (SpliNPV) is one of the most promising bioagents for the efficient control of insect pests. In this study, a chitinase gene (chitA) of a 1.8 kb DNA fragment was cloned and fully characterized from SpliNPV-EG1, an Egyptian isolate. A sequence of 601 amino acids was deduced when the gene was completely sequenced with a predicted molecular mass of 67 kDa for the preprotein. Transcriptional analyses using reverse transcription polymerase chain reaction (RT-PCR) revealed that chitA transcripts were detected first at 12 h post infection (hpi) and remained detectable until 168 hpi, suggesting their transcriptional regulation from a putative late promoter motif. In addition, quantitative analysis using quantitative RT-PCR showed a steady increase of 7.86-fold at 12 hpi in chitA transcription levels, which increased up to 71.4-fold at 120 hpi. An approximately 50 kDa protein fragment with chitinolytic activity was purified from ChitA-induced bacterial culture and detected by western blotting with an anti-recombinant SpliNPV chitinase antibody. Moreover, purification of the expressed ChitA recombinant protein showed in vitro growth inhibition of two different fungi species, Fusarium solani and F. oxysporum, confirming that the enzyme assembly and activity was correct. The results supported the potential role and application of the SpliNPV-ChitA protein as a synergistic agent in agricultural fungal and pest control programs.

• International Journal of Industrial Entomology and Biomaterials
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• 제15권1호
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• pp.35-38
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• 2007

In this study, ORF 46 of Bombyx mod nucleopolyhedrovirus(Bm46) fused with EGFP was expressed in Bombyx mod cell lines, larvae and pupae by BmNPV Bacmid system. Bm46 and EGFP were cloned into donor plasmid pFastBacHTb, which was transformed to competent DH10B cells containing helper and BmNPV bacmid by site-specific transposition. Recombinant bacmid was used to transfected BmN-4 cells to produce the recombinant baculovirus vBm-Bm46-EGFP. Recombination virus was injected into silkworm larvae and pupae. The expression of the fusion protein was monitored by examining green fluorescence using a fluorescent microscope. Intense fluorescence in cells and silkworm was observed at 4 days post-infection, indicating the Bm46-EGFP fusion gene was expressed successfully.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XII)
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• pp.315-319
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• 2003

A novel method is developed to yield virus titers in 10 h, is easy to .perform using 96-well plates, and applicable to both any Autographa californica nucleopolyhyderovirus (AcNPV) and Bombyx mori nucleopolyhedrovirus (BmNPV)-based recombinant baculovirus. This assay uses an antibody to a DNA-binding protein to detect the infected cells via immune-staining. The titer is determined by counting foci produced due to infection of virus under a fluorescent microscopy. The required incubation period was shortened considerably because infected cells expressed viral antigens at the post infection time of 4 h. Therefore, 10 hours were enough to estimate the virus titer including virus infection time, insect cell culture, and estimation of virus titer.

• 농약과학회지
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• 제12권3호
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• pp.283-290
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• 2008

베큘로바이러스는 일부 나비목 해충을 대상으로 방제하는 데 사용되고 있다. 그러나 화학농약에 비해 느린 살충효과 및 좁은 적용 해충으로 응용 범위에 한계를 갖고 있다. 본 연구는 이러한 한계를 극복하고자 곤충의 면역억제을 통해 바이러스 병원력을 제고시킬 수 있는 기술을 소개한다. 폴리드나바이러스는 일부 맵시벌 및 고치벌에 공생하는 곤충 DNA 바이러스 분류군이다. 프루텔고치벌(Cotesia plutellae) 유래 CpBV(Cotesia plutellae bracovirus)는 브라코바이러스에 속한 폴리드나바이러스로서 면역어제를 발휘하는 여러 유전자를 함유하고 있다. 이 가운데 7개의 CpBV유전자를 선발하고 이를 야생형Autographa California multiple nucleopolyhedrovirus(AcNPV)에 재조합하였다. 이들 재조합 베큘로바이러스를 이용하여 파밤나방(Spodoptera exigua)과 배추좀나방(Plutella xylostella)을 대상으로 생물 검정한 결과, 이들 대부분은 야생형의 바이러스와 유사하거나 우수한 살충력을 나타냈다. 특히 CpBV-ELP를 포함한 재조합 베큘로바이러스가 대조바이러스에 비해 살충시간을 약 2 일 이상단축시킴으로 가장 우수하였다. 이 재조합 베큘로바이러스는 농도에 따른 살충력증가와 배추를 가해하는 파밤나방을 대상으로 한 바이러스 살포 처리가 뚜렷한 방제효과를 나타내어 현장 적용 가능성을 제시하였다. 또한 본 연구는 이 재조합 바이러스의 살충력 제고 현상을 CpBV-ELP의 항바이러스 기작 억제라는 측면에서 고찰했다.

• 한국응용곤충학회지
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• 제43권1호
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• pp.55-60
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• 2004

담배거세미나방 핵다각체병바이러스(SINPV)의 살충력 증가를 위하여 유기산 및 기능성 물질을 첨가하여 활성을 검정한 결과는 다음과 같다. 핵다각체병바이러스(NPV) 1${\times}$$10^{5}$ PIBs/$m\ell$에 ascorbic acid, succinic acid, sulfanilic acid 2,000ppm을 바이러스 1${\times}$$10^{5}$ PIBs/$m\ell$에 첨가하였을 때 각각 7.0일, 7.일, 10.7일로 바이러스 단독으로 처리한 6.0일보다 더 높게 나타났으나 boric acid 2,000ppm을 첨가한 경우 L $T_{50}$은 4.5일로서 단독처리보다 1.5일 짧았다. 유충 체중변화에서도 boric acid는 2,000ppm에서 7일째 이후 생존하는 개체가 없어 가장 효과가 좋은 것으로 나타났으며 1,000ppm과 500ppm에서도 체중이 증가하지 않아 바이러스 활성 증진을 지속시키는 물질로 판단되었다. 기능성 물질과 혼합 처리에서는 바이러스 1${\times}$$10^4$ PIBs/$m\ell$ 단독 처리는 L $T_{50}$이 7.4일이 걸리는 반면 담배거세미나방 핵다각체병바이러스와 전해산화수, 키토산, 목초액 혼합처리는 모두 살충기간이 길어져 혼합효과가 없었다. 담배거세미나방 핵다각체병바이러스 농도 1.0${\times}$10$_{6}$, $10^{8}$ PIBs/$m\ell$와 기능성 물질을 혼합하였을 때도 같은 경향으로 오히려 바이러스 병원성 억제효과가 나타났다.

• 한국응용곤충학회지
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• 제60권4호
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• pp.379-386
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• 2021

아시아계통의 매미나방(Lymantria dispar asiatica) (나비목: 태극나방과)은 국내 토착해충으로서 지역에 따라 돌발적으로 대발생한 사례가 있으며, 다양한 수목 및 농작물에 피해를 끼치는 광식성 해충이다. 특히 2019년 이후로 경기도, 충청도, 경북 북부지역에서 대발생하여 산림 및 인근지역 도심에 발생하여 산림 및 도시민들의 정서적 피해를 끼치기도 했다. 본 연구에서는 2020-2021년 경북 예천지역에서 알집을 채집하여 사육한 결과, 매미나방 핵다각체병바이러스(LdMNPV) 감염에 의해 79.65% (321/403마리)는 사육중 사망하였다. 염기서열 분석은 2021년 국내 12 지역에서 매미나방 유충을 36마리를 조사한 결과, LdMNPV의 late expression factor-8 (lef-8), polyhedrin (polh) 유전자의 종내변이율이 0.80%, 0.86%로 확인됐다. NCBI database 자료와 비교 분석한 결과 일본의 LdMNPV와 가장 유사했으며, 터키의 LdMNPV와 가장 큰 차이를 나타냈다. 본 조사를 통하여 LdMNPV는 높은 감염율을 나타냈고 매미나방 중요한 개체군 조절인자중 한가지로 작용할 것으로 판단된다.

• International Journal of Industrial Entomology and Biomaterials
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• 제3권1호
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• pp.13-18
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• 2001

The role of polyhedrin in the polyhedra production in baculovirus Autograha californica Nucelopolyhedro-sisvirus (AcNPV) was studied by over-expression of AcNPV polyhedrin or heterologous polyhedrin from Bombyx mori (Bm) NPV or Spodoptera exigua (Se) NPV. The transfer vectors containing additional polyhedrin from AcNPV, BmNPV, or SeNPV were constructed and cotransfected with bacmid bApGOZA into Sf9 cells. The resulting recombinants, designated as vApAcPol, vApBmPol, and vApSePol were tonstructed, and the polyhedra production of the recombinant was characterized. All of the recombinants produced polyhedra in the nucleus, and the polyhedrin was over-expressed. Among three recombinants, vApAcPol and vApBmPol were discriminated by their larger polyhedra size than that of wild type AcNPV, and vApSePol also produced larger polyhedra than wild type SeNPV polyhedra.

• BMB Reports
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• 제35권6호
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• pp.562-567
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• 2002

In order to find the cellular interaction factors of the Heliothis armigera nuclear polyhedrosis virus capsid protein VP39, a Heliothis armigera cell cDNA library was constructed. Then VP39 was used as bait. The host actin gene was isolated from the cDNA library with the yeast two-hybrid system. This demonstrated that VP39 could interact with its host actin in yeast. In order to corroborate this interaction in vivo, the vp39 gene was fused with the green fluorescent protein gene in plasmid pEGFP39. The fusion protein was expressed in the Hz-AM1 cells under the control of the Autographa californica multiple nucleopolyhedrovirus immediate early gene promoter. The host actin was labeled specifically by the red fluorescence substance, tetramethy rhodamine isothicyanete-phalloidin. Observation under a fluorescence microscopy showed that VP39, which was indicated by green fluorescence, began to appear in the cells 6 h after being transfected with pEGFP39. Red actin cables were also formed in the cytoplasm at the same time. Actin was aggregated in the nucleus 9 h after the transfection. The green and red fluorescence always appeared in the same location of the cells, which demonstrated that VP39 could combine with the host actin. Such a combination would result in the actin skeleton rearrangement.

• BMB Reports
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• 제40권2호
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• pp.232-238
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• 2007

The p13 gene is uniquely present in Group II nucleopolyhedroviruses (NPVs) and some granuloviruses, but not in Group I NPVs. p13 gene was first described by our laboratory in Leucania separatamultiple nuclear polyhedrosis virus (Ls-p13) in 1995. However, the functions of Ls-P13 and of its homologues are unknown. When Ls-p13 was inserted into Autographa californica nucleopolyhedrovirus, a Group I NPV, polyhedra yield was inhibited. However, this inhibition was prevented when the leucine zipper-like domain of Ls-p13 was mutated. To determine the cause of this marked difference between Ls-P13 and leucine zipper mutated Ls-P13 (Ls-P13mL), oligomerization and secondary structure analyses were performed. High performance liquid chromatography and yeast two-hybrid assays indicated that neither Ls-P13 nor Ls-P13mL could form oligomers. Informatics and circular dichroism spectropolarimetry results further indicated marked secondary structural differences between Ls-P13 and Ls-P13mL. The LZLD of Ls-P13 has two extended heptad repeat units which form a hydrophobic surface, but it is short of a third hydrophobic heptad repeat unit for oligomerization. However, the mutated LZLD of Ls-P13mL lacks the above hydrophobic surface, and its secondary structure is markedly different. This difference in its secondary structure may explain why Ls-P13mL is unable to inhibit polyhedra yield.