• International Journal of Industrial Entomology and Biomaterials
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• 제9권2호
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• pp.217-223
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• 2004

A cathepsin L-like cysteine protease, v-cath, encoded by the baculovirus has been shown to playa role in host liquefaction. We have identified a v-cath gene in the silkworm virus, Bombyx mori nuclear polyhedrosis virus (BmNPV) K1 strain. The 969 bp v-cath has an open reading frame of 323 amino acids. A putative cleavage site and catalytic sites were conserved in BmNPV-K1 v-cath. The predicted three-dimensional structure of BmNPV-K1 v-cath revealed that the overall fold of BmNPV-K1 v-cath is similar to that of other proteases of the papain family. The deduced amino acid sequence of BmNPV-K1 v-cath showed 98% and 97% protein sequence identity to BmNPV T3 strain and to Autographa californica nuclear polyhedrosis virus, respectively. The BmNPV-K1 v-cath differed at 4 amino acid positions from BmNPV T3. The v-cath gene in BmNPV-K1 genome is located on the EcoRV 6 kb and XhoI 9 kb fragments. Northern hybridization analysis of BmNPV K1 v-cath gene revealed that it is expressed late in infection.

• International Journal of Industrial Entomology and Biomaterials
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• 제9권2호
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• pp.225-228
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• 2004

Superoxide dismutase (SOD) is an important enzyme which catalyzes superoxide radicals to hydrogen peroxide. A Cu, Zn sod-like gene was found in Bombyx mori nuclear polyhedrosis virus encoding 151 amino acids. To demonstrate its function, a recombinant virus named dsBmNPV with deleted sod gene was constructed. It was discovered that the sod gene was not essential for viral replication. Studies on growth of budded virus in BmN cells and superoxide dismutase and catalase activities in vivo after dsBmNPV infection showed that the titer of dsBmNPV decreased obviously comparing to wild type BmNPV, the sod gene was effective on genomic DNA replication of baculovirus, the peak of SOD activity of silkworm infected with wt-BmNPV appeared between 36 and 48 hrs post infection, and with dsBmNPV, it did not appear. And the changes of CAT activity after infection were similar to SOD activity.

• International Journal of Industrial Entomology and Biomaterials
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• 제2권2호
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• pp.149-153
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• 2001

The influence of baculovirus Bombyx mori Nuclear Polyhedrosis virus (BmNPV) infection on intermediary metabolic pathways in silkworm Bombyx mori L. was investigated. Studies revealed that NADP-linked malate dehydrogenase activity in hemolymph of infected silkworms at 96 hrs post infection (p.i.) with visible symptoms of infection was enhanced in comparison to healthy larvae of the same age. Also, NADP-dependent MDH activity was significantly lower in fat body cytosol of infected larvae at 96 hrs p.i. when compared to healthy larvae. Similarly, some biometabolic parameters like growth, protein content and cholesterol titer were observed to be influenced by baculovirus infection. While the growth of infected larvae was significantly retardedi protein content was also drastically reduced in both hemolymph and fat body tissues. Cholesterol titers however, was enhanced in infected larvae. The results observed herein point to a significant change in the normal biochemical and biometabolic pathways required for growth and development following BmNPV infection.

• International Journal of Industrial Entomology and Biomaterials
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• 제28권1호
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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.

• 한국잠사곤충학회지
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• 제34권2호
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• pp.20-25
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• 1992

유용물질을 생산할 수 있는 곤충 baculovirus expression vector system의 국내 개발을 위하여, Bm-NPV의 다각체 단백질 유전자를 탐색, 클로닝 하고 그 구조를 분석한 결과는 다음과 같다. 1. AcNPV의 다각체 단백질 유전자를 포함하고 있는 EcoRI-Ⅰ fragment내의 0.93kb를 probe로 하여 southern 분석한 결과, BmNPV의 다각체 단백질 유전자는 PstⅠ-F fragment(7.4Kb)에 위치하였다. 2. BmNPV의 다각체 단백질 유전자를 포함하는 PstⅠ-F fragment를 E. coli에 클로닝시켜서 pBmP-F라 명명하고, 다시 southern분석을 통해 subcloning하여 pBmP-H라 명명하였으며 pBmP-H의 제한효소 지도를 작성하였다. 3. pBmP-H의 염기서열분석결과 구조유전자를 포함한 1,259 bp의 염기서열이 결정되었다. Iatrou 등이 보고한 BmNPV 다각체 단백질 유전자의 염기서열과 비교한 결과 10개의 염기서열에서 차이를 보였으며, 74 Val이 Ile로, 76 Asn이 Ser으로 155 Met이 Val로 아미노산 변경된 결과를 보였다.

• 한국잠사곤충학회지
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• 제40권2호
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• pp.111-116
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• 1998

To construct transformed Bm5 cells, Autographa californica nuclear polyhedrosis virus (AcNPV)IE1 gene, an immediate early viral gene was firstly used in this study. AcNPV IE1 gene, which shares on 95.3% uncleotide sequence homology with Bombyx mori nuclear polyhedrosis virus (BmNPV) IE1 gene, was isolated and cloned into pBluescript. Neomycin gene from pKO-neo was inserted under the control of the IE1 promoter to yield pAcIE1-neo. The plasmid pAcIE1-neo was transfected into Bm5 or Sf9 cells, and neomycin-resistant cells were selected in TC100 medium containing 10% fetal bovine serum (FBS) and 1 mg/$m\ell$ G418 for two weeks. Individual clones were picked and each was amplified for further characterization. The genomic DNA from neomycin-resistnt cells was isolated and characterized by PCR using AcNPV IE1 gene-specific primers and by Southern blot analysis using neomycin gene probe. We concluded that AcNPV IE1 gene was functional in B. moridrived Bm5 cells as well as Spodaptera frugiperda-derived Sf9 cells to produce stably-transformed insect cells.

• 한국응용곤충학회지
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• 제28권3호
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• pp.105-112
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• 1989

누에(Bombyx mori)와 흰불나방(Hyphantria cunea)으로 부터 분리된 핵다각체병바이러스(nuclear polyhedrosis virus: NPV)를 동정하기 위하여 전자현미경 관찰한 결과, BmNPV 다각체의 크기는 $3 \mu\textrm{m}$ 정도의 18면체로 외형이 균일하였으나, HcNPV는 1.5-$2 \mu\textrm{m}$ 정도이며 부정형이었다. Alkaline protease를 부활화시킨 후 SDS-PAGE한 다각체 단백질의 分子물은 BmNPV가 30 KD, HcNPV는 31 KD인 major band와 이들의 중합체(polymer)로 생각되는 57 KD, 112 KD의 minor band들이 관찰되었다. 또한 virion 단백질을 SDS-PAGE한 후 은염색한 결과, BmNPV는 분자량 9.6~112 KD인 47개의 band, HcNPV 경우는 분자량 9.4~l11 KD인 48개는 band가 관찰되었다. BmNPV와 HcNPV DNA의 제한효소 처이에 의한 전기영동 패턴을 관찰했으며, 각각의 genome 크기는 BmNPV가 약 116.4 Kb, HcNPV의 약 114.6 Kb였다.

• 한국잠사곤충학회지
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• 제33권1호
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• pp.21-26
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• 1991

Bm 배양세포주(BmN4)에서 BmNPV의 다각체 단백질 합성과 DNA복제에 대한 실험결과는 다음과 같다. 1. BmNPV는 insect Grace's medium에서 배양되고 있는 BmN4 세포에서 NOV나 DNA로 감염시킨 경우 모두 잘 증식되었으며, 도립현미경 관찰 결과 접종 후 48시간이 경과하면서 다각체가 형성되기 시작하였다. 2. 또한 전자현미경으로 핵내 형성된 다각체와 협성중인 nucleocapsid 다발을 관찰하였으며, 바이러스 입자는 SNPV로 존재하였다. 3. Western blot분속에 의한 다각체 단백질의 합성은 접종 후 18시간부터 관찰되었으며, 다각체 단백질의 분자량은 30kd이었다. 4. Wild type BmNPV DNA와 Bm 세포(BmN4)에서 NOV 및 DNA 감염에 의해 형성된 바이러스 DNA간의 제한효소 패턴은 차이가 없었다.

• 한국응용곤충학회지
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• 제27권4호
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• pp.211-218
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• 1988

담배거세미나방(Spodoptera litura: SI), 누에(Bombyx mori: Bm) 및 흰불나방(Hyphantria cunea : Hc)으로부터 분리된 핵다각체병 바이러스(nuclear polyhedrosis virus : NPV)의 다각체의 단백질의 특성과 그에 대한 alkaline protease의 영향을 SDS-PAGE 및 혈정학적 방법으로 분석했다. Alkaline protease를 부활화시킨 후 다가체 단백질을 SDS-PAGE한 결과, BmNPV의 경우 30kD, SINPV와 HcNPV는 31kD의 단일 major band 및 이것들의 종합체(polymer)인 57kD와 66kD의 minor band들이 관찰되었다. Alkaline protease의 부활화를 성략한 SI NPV 다각체를 알칼리 용액으로 시간 차이를 두고 처리한 후 SDS-PAGE한 결고, 알칼리 처리시간이 경과함에 따라서 alkaline protease활성에 의해 다각체 단백질이 일정한 pattern으로 저분자화됨이 뚜렷하였다. SINPV 와 BmNPV 다각체 단백질의 항체를 제조하여 SINPV, BmNPV및 HcNPV 다각체 단백질간의 혈정학적 상동성을 이중형역광산법과 Western blot으로 비교한 결과는 3종 모두에서 공통 antigenic determinants의 존재가 인정되었으며 major 다각체 단백질의 종합체 형성과 alkaline protease에 의한 분해를 확인했다.

• International Journal of Industrial Entomology and Biomaterials
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• 제3권2호
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• pp.187-190
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• 2001

Inheritance pattern of resistance to Bombyx mori nuclear polyhedrosis virus (BmNPV) was studied in an Indian silkworm stock TX by single back-cross test method. The resistant parent ［TX］, susceptible parent ［HM］, their Fl, F2, and Fl progeny back-crossed to TX [BC(R)] and HM [BC(S)] were inoculated per os with a fixed concentration of BmNPV($0.5{\times}10^{th} PIB/ml$) on the first day of second stadium. The cumulative mortality was recorded until day $10^{\times}$ post-inoculation. The results show that the resistance to BmNPV in TX fellow mono Mendelian inheritance pattern. The resistance dominated over the susceptibility at Fl. At F2, the resistant and susceptible offspring segregated in 3:1 ratio whereas at BC(S), the resistant and susceptible offspring segregated in 1:1 ratio. The response of BC(R) was more or less like the resistant parent TX which confirms the involvement of a major dominant gene conferring resistance to BmNPV in TX. The possible mechanism of inheritance of resistance in TX is discussed.