• Korean journal of applied entomology
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• v.30 no.3
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• pp.212-218
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• 1991

Pathogenicity of Spodoptera exigua nuclear polyhedrosis virus (SeMNPV) against the host insect and 8 species of lepidopterous insects and cross infection of baculoviruses to third instar of S. exigua larvae were studied to determine as a biocontrol agent for S. exigua. The median lethal concentrations($LC_{50}$)of the SeMNPV to egg mass was $2.855\times10^5$ PIBs/ml and higher than that to the larvae of S. exigua. Mortality of the SeMNPV in third ins tar larvae was more increased than that in first and fifth instar of S. exigua larvae by 1.16 and 4.11 times, respectively. The median lethal times($LT_{50}$) to $1.56\times10^6$ PIBs/ml was in the range of 4.25 to 5.04 days. Infectivity of the SeMNPV against eight species of lepidopterous insects was showed only in the host insect, S. exigua. Autographa cali/ornica MNPV, Mamestra barassicae MNPV, and Trichoplusia ni MNPV were cross-infected to third instar of S. exigua larvae among ten of baculoviruses tested.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2004.10a
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• pp.26-27
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• 2004

• Journal of Sericultural and Entomological Science
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• v.38 no.1
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• pp.42-47
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• 1996

To investigate the host range determining factors of nuclear polyhedrois virus (NPV), Autographa california NPV and Bombyx mori NPV were coinfected into the two different cell lines, BmN-4 and Sf-9. The recombinant baculoviruses, RecS-A6 and RecB-727 which have an expanded host range, were isolated from Sf-9 and BmN-4 cell lines, respectively. The molecular biological characteristics of the recombinant baculoviruses were investigated. The pathogenicity of RecB-727 was similar to that of wild type BmNPV, while the pathogenicity of RecS-A6 was relatively lower than that of wild type BmNPV. The restriction enzyme digestion patterns of parental viruses and recombinant viruses showed that the recombinant virus has an expanded host range by genetic recombination. Southern blot analysis revealed that the p10 gene of RecB-727 was derived from AcNPV genomic DNA, while RecS-A6 has p10 gene of BmNPV in a viral genome. To investigate the host range expansion mechanism of recombinant baculovirus, HindIII-SacI 0.6 kb DNA fragments of RecS-A6 and RecB-727 were cloned and sequenced. The results showed that of wild type BmNPV helicase gene, suggesting that the expanded host range of recombinant baculoviruses was due to the insertion of BmNPV helicase gene into AcNPV viral genome.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2005.04a
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• pp.47-47
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• 2005

• Journal of Sericultural and Entomological Science
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• v.38 no.1
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• pp.36-41
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• 1996

Recombinant baculoviruses having expanded host range were selected by coinfection of Autographa california NPV and Bombyx mori NPV into Sf-9 and BmN-4 insect cell lines. In order to determine the polyhedra morhplogy of RecS-A6, one of a recombinant baculovirus, polyhedra of RecS-A6 produced in insect cells were observed by phase contrast microscope and scanning electron microscope. The results revealed that the recombinant baculovirus had a various polyhedra morphology which was different from its parental viruses, suggesting that the various morhpology of recombinant baculovirus with an expanded host range was due to the genetic recombination of viral genome. To analyze the genomic recombinantion of the recombinant baculoviruses, genomic DNAs of two parent viruses and RecS-A6 were digested with restriction endonuclease and subjected to agarose gel electrophoresis. Southern blot analysis revealed that RecS-A6 has two polyhedrin gene of AcNPV and BmNPV in a viral genome. Polyhedral protein of recombinant baculovirus was analysed by SDS-PAGE. The result showed that molecular weight of polyhedral protein of RecS-A6 containing two polyhedrin gene of AcNPV and BmNPV was as the 31 kDa band of AcNPV and 30 kDa band of BmNPV.

• International Journal of Industrial Entomology and Biomaterials
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• v.28 no.1
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• pp.10-18
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• 2014

Baculoviruses base vectors come to be regarded as methods for in vivo gene delivery and transient expression to the silkworm. In the case of silkworm, B. mori, two types of baculoviruses, AcNPV (Autographa californica nuclear polyhedrosis virus) and BmNPV (Bombyx mori nuclear polyhedrosis virus), are potentially applicable as vectors. Recently, AcNPV showed promising results with some silkworm strains despite different host-specificities. We searched for a highly-permissive silkworm strain in the B. mori stocks of Kyungpook National University that could produce high levels of recombinant protein. Seventy strains were screened using the recombinant AcNPV/BmA3-Luc virus. Based on the measured luciferase activity, the strains could be divided into three groups, high-, middle-, and low-permissive strains, according to their relative recombinant protein expression levels. At 48 hours post-injection, the luciferase activity in the high-permissive strains was 500-fold greater than that of the low-permissive strains. At 72 hours post-injection, a significant elevation in luciferase activity was observed in the hemocytes of all strains. Then, based on the above results, the High Permissive Strain (HPS) S10 and the Low Permissive Strain (LPS) S39 were pick up and was carried out Dot blotting, RT-PCR and Real time PCR.

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.5
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• pp.352-355
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• 2004

Heliothis zea (HzAM1) insect cells were immobilized in microspheres by sodium-cellulosesulfate (NaCS) and polydiallyldimethylammoniumchloride (PDADMAC). The highest HzAMl cell density was $7.5{\times}10^7$ cells/mL in the microspheres. After infection of the immobilized cells by Heliothis zea single nuclear polyhedrosis virus (HzSNPV), the highest concentration of HzSNPV (polyhedral inclusion bodies: PIBs) produced was $2.87{\times}10^{10}$ PIBs/mL in the microspheres.

• BMB Reports
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• v.31 no.6
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• pp.585-589
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• 1998

The herpes simplex virus type-1 (HSV-1)-encoded DNA polymerase consists of two subunits, the products of the UL30 and UL42 genes. UL30 and UL42 were coexpressed in Sf9 cells infected with recombinant baculoviruses carrying the two genes. The UL30 and UL42 gene products remained tightly associated throughout the purification, which led to a near homogeneous heterodimer composed of the DNA polymerase and UL42 protein. The DNA polymerase-UL42 protein heterodimer, purified from the recombinant baculovirus-infected Sf9 cells, showed the same high degree of processivity of deoxynucleotide polymerization as the enzyme purified from the HSV-1 infected primate cells. Like the latter, it contained a 3'-5' exonuclease activity that specifically hydrolyzes an incorrectly matched nucleotide at the 3' terminus of a primer, thereby contributing to the fidelity of DNA replication.

• Parasites, Hosts and Diseases
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• v.37 no.4
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• pp.277-283
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• 1999

To investigate the development of a subunit vaccine against theileriosis in cattle, the DNA fragments encoding piroplasm surface protein (p33) of Theileria sergenti of a Korean isolate were expressed in baculoviruses. The expressed p33 was characterized by indirect fluorescent antibody (IFA) and western blotting analysis. The expression of p33 was mainly detected on the surface of infected Sf21 cells by IFA. The immunoblotting analysis revealed the presence of a same molecular weight protein band of p33. The antigenicity of expressed polypeptide was further examined through the inoculation of a guinea pig. The sera of guinea pigs immunized with p33 expressed cell Iysate showed similar fluorescent antibody patterns and reacted with the same molecular weight protein of T. sergenti in immunoblotting analysis, thus indicating that this protein can be a promising candidate for a subunit vaccine in the future.

• BMB Reports
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• v.40 no.1
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• pp.65-71
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• 2007

The Helicoverpa armigera nucleopolyhedrovirus (HearNPV) ORF80 (ha80) has 765 bp encoding a protein with approximately 254 amino acids and a predicted molecular weight of 30.8 kDa. Homologues of ha80 are found in most baculovirus sequences, including those from lepidopteran NPVs, lepidopteran granuloviruses (GVs), hymenopteran baculoviruses, and one dipteran baculovirus, yet their functions remain unclear. In this study we characterized ha80, and showed that it was transcribed late in infected host cells (HzAM1). The product of ha80 was a 31 kDa protein that was not a structural protein of budded virus (BV) or occlusion-derived virus (ODV) particles. Ha80 was first detected in the cytoplasm of infected HzAM1 cells at 12 h p.i., and was observed in the nucleus at later stages of infection, suggesting that it may be involved in transporting viral proteins into the host cell nucleus or play its roles in the nucleus.