scholarly journals Bombyx mori nucleopolyhedrovirus BmP95 plays an essential role in budded virus production and nucleocapsid assembly

2013 ◽  
Vol 94 (7) ◽  
pp. 1669-1679 ◽  
Author(s):  
Xingwei Xiang ◽  
Yunwang Shen ◽  
Rui Yang ◽  
Lin Chen ◽  
Xiaolong Hu ◽  
...  
Keyword(s):  
Bombyx Mori ◽  
Virus Production ◽  
Full Length ◽  
Tubular Structures ◽  
Bombyx Mori Nucleopolyhedrovirus ◽  
Budded Virus ◽  
Conserved Gene ◽  
Fluorescence And Light Microscopy

Bombyx mori nucleopolyhedrovirus (BmNPV) BmP95 is a highly conserved gene that is found in all of the baculovirus genomes sequenced to date and is also found in nudiviruses. To investigate the role of BmP95 in virus infection in vitro, a BmP95 deletion virus (vBmP95-De) was generated by homologous recombination in Escherichia coli. Fluorescence and light microscopy and titration analysis indicated that the BmP95 deletion bacmid led to a defect in production of infectious budded virus (BV). However, deletion of BmP95 did not affect viral DNA replication. Electron microscopy showed that masses of aberrant tubular structures were present in cells transfected with the BmP95 deletion bacmid, indicating that deletion of BmP95 affected assembly of the nucleocapsid. This defect could be rescued by insertion of full-length BmP95 into the polyhedrin locus of the BmP95-knockout bacmid but not the N-terminal domain of BmP95. Together, these results showed that full-length BmP95 is essential for BV production and is required for nucleocapsid assembly.

Open reading frame 60 of the Bombyx mori nucleopolyhedrovirus plays a role in budded virus production

2010 ◽  
Vol 151 (2) ◽  
pp. 185-191 ◽  
Author(s):  
Zhong-Jian Guo ◽  
Li-Hua Qiu ◽  
Shi-Heng An ◽  
Qin Yao ◽  
Enoch Y. Park ◽  
...  
Keyword(s):  
Bombyx Mori ◽  
Virus Production ◽  
Open Reading Frame ◽  
Bombyx Mori Nucleopolyhedrovirus ◽  
Reading Frame ◽  
Budded Virus

scholarly journals Bombyx mori nucleopolyhedrovirus ORF56 encodes an occlusion-derived virus protein and is not essential for budded virus production

2008 ◽  
Vol 89 (5) ◽  
pp. 1212-1219 ◽  
Author(s):  
Hai-Jun Xu ◽  
Zhang-Nv Yang ◽  
Jin-Fang Zhao ◽  
Cai-Hong Tian ◽  
Jun-Qing Ge ◽  
...  
Keyword(s):  
Bombyx Mori ◽  
Cultured Cells ◽  
Virus Production ◽  
Core Gene ◽  
Virus Protein ◽  
Infected Cells ◽  
Budded Virus ◽  
Larval Bioassay

Bombyx mori nucleopolyhedrovirus ORF56 (Bm56) is a baculovirus core gene that is highly conserved in all baculoviruses that have had their genomes sequenced to date. Its transcripts in BmNPV-infected cells could be detected from 12 h post-infection (p.i.) and the encoded protein could be detected at 16 h p.i. by using a polyclonal antibody against glutathione S-transferase–Bm56 fusion protein. Western blot analysis showed that Bm56 is a structural component of the occlusion-derived virus nucleocapsid. Subsequent confocal microscopy revealed that Bm56 was distributed in the outer nuclear membrane and the intranuclear region of infected cells. To investigate the role of Bm56 in virus replication, a Bm56-knockout bacmid of BmNPV was constructed via homologous recombination in Escherichia coli. The Bm56 deletion had no effect on budded virus (BV) production in cultured cells; however, the deletion affected occlusion-body morphogenesis. A larval bioassay demonstrated that the Bm56 deletion did not reduce infectivity, whereas it resulted in a 50 % lethal time that was 16–18 h longer than that of the wild-type bacmid at every dose used in this study. These results indicate that Bm56 facilitates efficient virus production in vivo; however, it is not essential for BV production in vitro.

scholarly journals Characterization of AcMNPV with a deletion of ac69 gene

2011 ◽  
Vol 2 (1) ◽  
pp. 4
Author(s):  
Jianhao Ke ◽  
Jinwen Wang ◽  
Riqiang Deng ◽  
Lin Lin ◽  
Bei Jinlong ◽  
...  
Keyword(s):  
Spodoptera Frugiperda ◽  
Trichoplusia Ni ◽  
Virus Production ◽  
Viral Infectivity ◽  
Methyltransferase Activity ◽  
Budded Virus

<p>ORF69 (Ac69) of <em>Autographa californica</em> multiple nucleopolyhedrovirus (Ac<em>M</em>NPV) is conserved in some baculovirus genomes. Although it has been shown that Ac69 has cap 0-dependent methyltransferase activity and is not required for budded virus production in <em>Spodoptera frugiperda</em> Sf-9 cells, its role in occlusion-derived virus synthesis and virus oral infectivity is not known. This paper describes generation of an <em>ac69</em> knockout Ac<em>M</em>NPV bacmid mutant and analyses of the influence of <em>ac69</em> deletion on the viral infectivity in Sf-9 cells and <em>Trichoplusia ni</em> larvae so as to investigate the role of <em>ac69 in the viral life cycle. Results indicated that ac69</em> deletion has little effect on the production rates and morphogenesis of budded virus and occlusion-derived virus in Sf-9 cells. In addition, animal experiment revealed that the deletion mutant did not affect Ac<em>M</em>NPV infectivity for <em>Trichoplusia ni</em> larvae in LD<sub>50</sub> and LT<sub>50</sub> bioassay when administered orally. These results suggest that <em>ac69</em> may be dispensable for viral infectivity both in vitro and in vivo.</p>

Disruption of Bombyx mori nucleopolyhedrovirus ORF71 (Bm71) results in inefficient budded virus production and decreased virulence in host larvae

Virus Genes ◽  
2012 ◽  
Vol 45 (1) ◽  
pp. 161-168 ◽  
Author(s):  
Min-Juan Zhang ◽  
Ruo-Lin Cheng ◽  
Yi-Han Lou ◽  
Wan-Lu Ye ◽  
Tao Zhang ◽  
...  
Keyword(s):  
Bombyx Mori ◽  
Virus Production ◽  
Bombyx Mori Nucleopolyhedrovirus ◽  
Budded Virus

scholarly journals Bombyx mori nucleopolyhedrovirus ORF9 is a gene involved in the budded virus production and infectivity

2009 ◽  
Vol 90 (1) ◽  
pp. 162-169 ◽  
Author(s):  
Z.-N. Yang ◽  
H.-J. Xu ◽  
S. M. Thiem ◽  
Y.-P. Xu ◽  
J.-Q. Ge ◽  
...  
Keyword(s):  
Bombyx Mori ◽  
Virus Production ◽  
Bombyx Mori Nucleopolyhedrovirus ◽  
Budded Virus

scholarly journals Functional analysis of the putative antiapoptotic genes, p49 and iap4, of Spodoptera litura nucleopolyhedrovirus with RNAi

2008 ◽  
Vol 89 (8) ◽  
pp. 1873-1880 ◽  
Author(s):  
Qian Yu ◽  
Tiehao Lin ◽  
Guozhong Feng ◽  
Kai Yang ◽  
Yi Pang
Keyword(s):  
Spodoptera Litura ◽  
Virus Production ◽  
Host Cells ◽  
Homology Search ◽  
Pcr Analysis ◽  
Viability Analysis ◽  
Infected Cells ◽  
Budded Virus ◽  
Almost All

A homology search of a public database revealed that Spodoptera litura nucleopolyhedrovirus (SpltNPV) possesses two putative, antiapoptotic genes, p49 and inhibitor of apoptosis 4 (iap4), but their function has not been investigated in its native host cells. In the present study, we used RNA interference (RNAi) to silence the expression of Splt-iap4 and Splt-p49, independently or together, to determine their roles during the SpltNPV life cycle. RT-PCR analysis and Western blot analysis showed the target gene expression had been knocked out in the SpltNPV-infected SpLi-221 cells after treatment with Splt-p49 or Splt-iap4 double-stranded RNA (dsRNA), respectively, confirming that the two genes were effectively silenced. In SpltNPV-infected cells treated with Splt-p49 dsRNA, apoptosis was observed beginning at 14 h, and almost all cells had undergone apoptosis by 48 h. In contrast, budded virus production and polyhedra formation progressed normally in infected cells treated with Splt-iap4 dsRNA. Cell viability analysis showed that Splt-IAP4 had no synergistic effect on the inhibition of apoptosis of SpLi-221 cells induced by SpltNPV infection. Interestingly, after Splt-iap4 dsRNA treatment, cells did not congregate like those infected with SpltNPV in the early infection phase, implying an unknown role of baculovirus iap4. Our results determine that Splt-p49 is necessary to prevent apoptosis; however, Splt-iap4 has no antiapoptotic function during SpltNPV infection.

scholarly journals Exon 9-deleted CETP inhibits full length-CETP synthesis and promotes cellular triglyceride storage

2020 ◽  
Vol 61 (3) ◽  
pp. 422-431 ◽  
Author(s):  
Lahoucine Izem ◽  
Yan Liu ◽  
Richard E. Morton
Keyword(s):  
Lipid Metabolism ◽  
Lipid Droplets ◽  
Full Length ◽  
Intracellular Lipid ◽  
Transfer Protein ◽  
Lipid Phenotype ◽  
Exon 9 ◽  
And Storage

Cholesteryl ester transfer protein (CETP) exists as full-length (FL) and exon 9 (E9)-deleted isoforms. The function of E9-deleted CETP is poorly understood. Here, we investigated the role of E9-deleted CETP in regulating the secretion of FL-CETP by cells and explored its possible role in intracellular lipid metabolism. CETP overexpression in cells that naturally express CETP confirmed that E9-deleted CETP is not secreted, and showed that cellular FL- and E9-deleted CETP form an isolatable complex. Coexpression of CETP isoforms lowered cellular levels of both proteins and impaired FL-CETP secretion. These effects were due to reduced synthesis of both isoforms; however, the predominate consequence of FL- and E9-deleted CETP coexpression is impaired FL-CETP synthesis. We reported previously that reducing both CETP isoforms or overexpressing FL-CETP impairs cellular triglyceride (TG) storage. To investigate this further, E9-deleted CETP was expressed in SW872 cells that naturally synthesize CETP and in mouse 3T3-L1 cells that do not. E9-deleted CETP overexpression stimulated SW872 triglyceride synthesis and increased stored TG 2-fold. Expression of E9-deleted CETP in mouse 3T3-L1 cells produced a similar lipid phenotype. In vitro, FL-CETP promotes the transfer of TG from ER-enriched membranes to lipid droplets. E9-deleted CETP also promoted this transfer, although less effectively, and it inhibited the transfer driven by FL-CETP. We conclude that FL- and E9-deleted CETP isoforms interact to mutually decrease their intracellular levels and impair FL-CETP secretion by reducing CETP biosynthesis. E9-deleted CETP, like FL-CETP, alters cellular TG metabolism and storage but in a contrary manner.

The validation of the role of several genes related to Bombyx mori nucleopolyhedrovirus infection in vivo

2021 ◽  
Vol 106 (2) ◽  
Author(s):  
Xue‐yang Wang ◽  
Chun‐xiao Zhao ◽  
Xin Wang ◽  
Zi‐qin Zhao ◽  
Zhi‐hao Su ◽  
...  
Keyword(s):  
Bombyx Mori ◽  
Bombyx Mori Nucleopolyhedrovirus

Biologic consequences of androgen receptor (AR) activity in MDV3100-resistant LNCaP cells and dependence on AR full length.

2014 ◽  
Vol 32 (4_suppl) ◽  
pp. 74-74
Author(s):  
Yoshiaki Yamamoto ◽  
Yohann Loriot ◽  
Eliana Beraldi ◽  
Tianyuan Zhou ◽  
Youngsoo Kim ◽  
...  
Keyword(s):  
Gene Expression ◽  
Androgen Receptor ◽  
Cell Growth ◽  
Functional Role ◽  
Full Length ◽  
Lncap Cells ◽  
Exon 1

74 Background: While recent reports link androgen receptor (AR) variants (AR-Vs) to castration resistant prostate cancer (CRPC), the biological significance of AR-Vs in AR-regulated cell survival and proliferation, independent of AR full length (AR-FL), remains controversial. To define the functional role of AR-FL and AR-Vs in MDV3100-resistant (MDV-R), we designed antisense oligonucleotide (ASO) targeting exon 1 and exon 8 in AR to knockdown AR-FL alone or in combination with AR-Vs and examined these effects in MDV-R LNCaP-derived cells in vitro and in vivo. Methods: We generated by selection MDV-R LNCaP-derived sub-lines that uniformly expressed high levels of both AR-FL and AR-V7 compared to CRPC LNCaP xenografts. Cell growth rates, protein and gene expression were analyzed using crystal violet assay, western blotting and real-time PCR, respectively. Exon 1 and 8 AR-ASO were evaluated in MDV-R49F CRPC LNCaP xenografts. Results: AR-V7 was transiently transfected in MDV-R49F cells and differential knockdown of AR-V7 and/or AR-FL by exon 1 versus exon 8 AR-ASO was used to evaluate relative biologic contributions of AR-FL versus AR-V7 in MDV-R LNCaP AR-V7 overexpressing cells. Exon 1 and 8 AR-ASO treatment in these cells similarly decreased prostate-specific antigen (PSA) expression and induced apoptosis as measured by caspase-3 and PARP cleavage and cell growth inhibition. To further define the functional role of AR-Vs in MDV-R LNCaP cells, we used a CE3 siRNA that specifically silenced AR-V7, but not AR-FL in MDV-R LNCaP cells. AR-V7 knockdown did not decrease PSA levels, did not induce apoptosis, and did not inhibit cell growth. In MDV-R LNCaP cells, exon 1 and 8 ASO similarly suppressed cell growth and AR-regulated gene expression in vitro and in vivo. Conclusions: These results indicate that the AR remains an important driver of MDV3100 resistance and, the biologic consequences mainly driven by AR-FL in MDV-R LNCaP models.

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