scholarly journals Helicoverpa armigera nucleopolyhedrovirus occlusion-derived virus-associated protein, HA100, affects oral infectivity in vivo but not virus replication in vitro

2011 ◽  
Vol 92 (6) ◽  
pp. 1324-1331 ◽  
Author(s):  
Sijiani Luo ◽  
Yanfang Zhang ◽  
Xushi Xu ◽  
Marcel Westenberg ◽  
Just M. Vlak ◽  
...  
Keyword(s):  
Virus Replication ◽  
Helicoverpa Armigera ◽  
Virus Production ◽  
Control Virus ◽  
Helicoverpa Armígera ◽  
Occlusion Bodies ◽  
Lethal Time ◽  
Budded Virus

ORF100 (ha100) of Helicoverpa armigera nucleopolyhedrovirus (HearNPV) has been reported as one of the unique genes of group II alphabaculoviruses encoding a protein located in the occlusion-derived virus (ODV) envelope and nucleocapsid. The protein consists of 510 aa with a predicted mass of 58.1 kDa and is a homologue of poly(ADP–ribose) glycohydrolase in eukaryotes. Western blot analysis detected a 60 kDa band in HearNPV-infected HzAM1 cells starting at 18 h post-infection. Transient expression of GFP-fused HA100 in HzAM1 cells resulted in cytoplasmic localization of the protein, but after superinfection with HearNPV, GFP-fused HA100 was localized in the nucleus. To study the function of HA100 further, an ha100-null virus was constructed using bacmid technology. Viral one-step growth curve analyses showed that the ha100-null virus had similar budded virus production kinetics to that of the parental virus. Electron microscopy revealed that deletion of HA100 did not alter the morphology of ODVs or occlusion bodies (OBs). However, bioassays in larvae showed that the 50 % lethal concentration (LC50) value of HA100-null OBs was significantly higher than that of parental OBs; the median lethal time (LT50) of ha100-null OBs was about 24 h later than control virus. These results indicate that HA100 is not essential for virus replication in vitro. However, it significantly affects the oral infectivity of OBs in host insects, suggesting that the association HA100 with the ODV contributes to the infectivity of OBs in vivo.

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 Potensi Nematoda Patogen Serangga Steinernema spp. dalam Pengendalian Hama Utama Tanaman Kapas

2016 ◽  
Vol 1 (2) ◽  
pp. 101
Author(s):  
Heri Prabowo ◽  
I.G.A.A. Indrayani
Keyword(s):  
Helicoverpa Armigera ◽  
Insect Pests ◽  
Soil Surface ◽  
Tenebrio Molitor ◽  
Pectinophora Gossypiella ◽  
Helicoverpa Armígera ◽  
Soy Bean Oil

<p>Steinernema spp. memiliki potensi untuk mengendalikan hama tanaman kapas seperti Helicoverpa armigera dan Pectinophora gossypiella. Steinernema spp. mampu menyebabkan mortalitas P. gossypiella dan H. armi-gera berturut-turut sebesar 31,6–55,4 dan 46,3–63,8%. Steinernema spp. memiliki kemampuan membunuh lebih baik pada P. gossypiella, sedangkan kemampuan reproduksi dalam inangnya lebih baik pada H. armi-gera. Steinernema spp. mampu menginfeksi serangga inang lebih baik pada stadium ulat lebih tua diban-dingkan stadium muda. Steinernema spp. dapat diproduksi secara in vivo dan in vitro. Produksi secara in vivo dapat menggunakan Tenebrio molitor, Tirathaba rufivena, dan Attacus atlas. Produksi secara in vitro dapat menggunakan usus ayam, lemak sapi, dan minyak kedelai. Perlu dikembangkan formulasi Steinerne-ma spp. yang murah dan efektif untuk mengendalikan hama di atas permukaan tanah. Selain itu diperlukan pencarian isolat Steinernema spp. yang virulen dan cepat membunuh hama sasaran.</p><p> </p><p>Steinernema spp. could be potentially used for controlling H. armigera and P. gossypiella on cotton. Steiner-nema spp. causes mortality on P. gossypiella and H. armigera 31,6–55,4 and 46,3–63,8% respectively. The nematode causes a higher mortality on P. gossypiella than on H. armigera, however, produces more juvenile infective on H. armigera than on P. gossypiella. Higher successful infections of Steinernema spp. occurs on late larval stadium than on early one. Production of Steinernema spp. can be in vivo using Tenebrio molitor, Tirathaba rufivena, and Attacus atlas; and in vitro using chicken intestinum, cow lipid, and soy bean oil. For effecttively use, this nematode need to be formulated especially for controlling insect pests on soil surface, as well as finding the more virulent isolates against the target insects.</p>

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>

In Silico and in Vivo Investigations of Bioagent Helicoverpa Nucleopolyhedrovirus against Helicoverpa armigera in Chickpea

2021 ◽  
Vol 9 (2) ◽  
pp. 21-32
Author(s):  
Ritu Srivastava ◽  
◽  
Amritesh Chandra Shukla ◽  
Keyword(s):  
Green Tea ◽  
Rice Bran ◽  
Helicoverpa Armigera ◽  
Maximum Yield ◽  
3D Structure ◽  
Homology Model ◽  
In Vitro Toxicity ◽  
Helicoverpa Armígera

During investigations; homology model of 3D-structure was built for sequence of polyhedrin protein of Helicoverpa armigera nucleopolyhedrovirus, containing 246 amino acids (Accession: ACI05106.1 GI: 205946055), and evaluated through multiple tools/ applications to judge extent of accuracy in light of existing crystal structure. Further, in vivo experiments were conducted and determined response of different adjuvants with HaNPV and their efficacy. The pooled mean mortality of larvae exposed to virus mixed with 5% green tea and 5% rice bran filtrates (8.3 larvae per 25 plants) was differ significantly from control (15.8 larvae per 25 plants), suggesting that UV protectants & diet enhancer (mannitol) has ability to protect stability of virulence of the virus, under field conditions. The minimum percent pod damage of 8.6% and maximum yield of 1604.8 Kg ha-1 at harvesting was recorded with formulation of indigenous BHA virus isolate @ 2.2 x 105 POBs mL-1 mixed with Roket @50 ppm; followed by formulation with mannitol (@ 1% + green tea 5% + 5% rice bran filtrates) with percent pod damage of 16.8 % and yield of 1045.8 Kg ha-1 of chickpea. Furthermore, in vitro toxicity of fresh virus suspension @ 250 mL ha-1 was recorded more toxic in terms of percent mortality and LT50 (5.65 days). However, three months stored HaNPV formulations [(A) mannitol @ 1%+ green tea@ 5% and (B) mannitol @ 1% + green tea 5% + 5% rice bran filtrates] were more effective in larval reduction with LT50 of 7.89 and 6.00 days, respectively. Virus mixed with 5% green tea and 5% rice bran filtrates gave stability to formulation up-to one year with LT50 of 7.64 days. Findings showed that HaNPV formulations with mannitol (B) have potential that can be used in integrated manner with other IPM practices, to reduce the use of toxic synthetic pesticides in chickpea.

scholarly journals Identification of a Hydrophobic Domain of HA2 Essential to Morphogenesis of Helicoverpa armigera Nucleopolyhedrovirus

2008 ◽  
Vol 82 (8) ◽  
pp. 4072-4081 ◽  
Author(s):  
Qian Wang ◽  
Yun Wang ◽  
Changyong Liang ◽  
Jianhua Song ◽  
Xinwen Chen
Keyword(s):  
Helicoverpa Armigera ◽  
Fluorescent Protein ◽  
Hydrophobic Domain ◽  
C Terminus ◽  
Localization Analysis ◽  
Helicoverpa Armígera ◽  
Budded Virus ◽  
Green Fluorescent ◽  
Vitro Analysis

ABSTRACT The HA2 protein of the Helicoverpa armigera single-nucleocapsid nucleopolyhedrovirus (HearNPV) is a WASP homology protein capable of nucleating branched actin filaments in the presence of the Arp2/3 complex in vitro. To determine the role of ha2 in the HearNPV life cycle, ha2 knockout and ha2 repair bacmids were constructed. Transfection and infection analysis demonstrated that the ha2 null bacmid was unable to produce infectious budded virus (BV), while the repair bacmid rescued the defect. In vitro analysis demonstrated that the WCA domain of HA2 accelerates Arp2/3-mediated actin assembly and is indispensable to the function of HA2. However, analysis of the repaired recombinant with a series of truncated ha2 mutants demonstrated that the WCA domain was essential but not enough to yield infectious virions, and a hydrophobic domain (H domain) consisting of amino acids (aa) 167 to 193 played a pivotal role in the production of BV. Subcellular localization analysis with enhanced green fluorescent protein fusions showed that the H domain functioned as a nuclear localization signal. In addition, deletion of the C terminus of the ha2 product, a phosphatidylinositol 4-kinase homolog, dramatically decreased the viral titer, while deletion of 128 aa from the N terminus did not affect HA2 function.

Helicoverpa armigera nucleopolyhedrovirus orf81 is a late gene involved in budded virus production

2014 ◽  
Vol 159 (8) ◽  
pp. 2011-2022 ◽  
Author(s):  
Xiao-Feng Li ◽  
Huan Yu ◽  
Chuan-Xi Zhang ◽  
Hui Chen ◽  
Dun Wang
Keyword(s):  
Helicoverpa Armigera ◽  
Virus Production ◽  
Late Gene ◽  
Helicoverpa Armígera ◽  
Budded Virus

Effects of dietary quercetin on performance and cytochrome P450 expression of the cotton bollworm, Helicoverpa armigera

2015 ◽  
Vol 105 (6) ◽  
pp. 771-777 ◽  
Author(s):  
D. Liu ◽  
Y. Yuan ◽  
M. Li ◽  
X. Qiu
Keyword(s):  
Cytochrome P450 ◽  
Helicoverpa Armigera ◽  
Adult Emergence ◽  
Cotton Bollworm ◽  
Molecular Response ◽  
Terrestrial Plants ◽  
P450 Expression ◽  
Helicoverpa Armígera

AbstractQuercetin is ubiquitous in terrestrial plants. The cotton bollworm Helicoverpa armigera as a highly polyphagous insect has caused severe crop losses. Until now, interactions between this pest and quercetin are poorly understood at the biochemical and molecular levels. In this study, we investigated the in vivo effects of quercetin on performance of cotton bollworm and on cytochrome P450 (P450) expression. Deleterious effects of quercetin on the performance of the cotton bollworm, including growth, survival, pupation and adult emergence were observed after oral administration of 3 and 10 mg g−1 quercetin to larvae since the third instar, whereas no significant toxic effect was found at 0.1 mg g−1 quercetin treatment. Piperonyl butoxide treatment enhanced the toxicity of quercetin. In vitro metabolism studies showed that quercetin was rapidly transformed by gut enzymes of fifth instar larvae of the cotton bollworm. qRT–PCR results revealed that the effect of quercetin on P450 expression was tissue- and dose-specific. Quercetin regulated P450 expression in a mild manner, and it could serve as P450 inducer (CYP337B1, CYP6B6) or repressor (CYP337B1, CYP6B7, CYP6B27, CYP9A14, CYP6AE11, and CYP4M7). These findings are important for advancing our understanding of the biochemical and molecular response of insects to plant toxins and have implications for a smart pest control.

scholarly journals New Resistance Mechanism in Helicoverpa armigera Threatens Transgenic Crops Expressing Bacillus thuringiensis Cry1Ac Toxin

2005 ◽  
Vol 71 (5) ◽  
pp. 2558-2563 ◽  
Author(s):  
Robin V. Gunning ◽  
Ho T. Dang ◽  
Fred C. Kemp ◽  
Ian C. Nicholson ◽  
Graham D. Moores
Keyword(s):  
Bacillus Thuringiensis ◽  
Helicoverpa Armigera ◽  
Resistance Mechanism ◽  
Transgenic Cotton ◽  
In Vivo Studies ◽  
Cry1ac Toxin ◽  
Helicoverpa Armígera ◽  
History Of

ABSTRACT In Australia, the cotton bollworm, Helicoverpa armigera, has a long history of resistance to conventional insecticides. Transgenic cotton (expressing the Bacillus thuringiensis toxin Cry1Ac) has been grown for H. armigera control since 1996. It is demonstrated here that a population of Australian H. armigera has developed resistance to Cry1Ac toxin (275-fold). Some 70% of resistant H. armigera larvae were able to survive on Cry1Ac transgenic cotton (Ingard) The resistance phenotype is inherited as an autosomal semidominant trait. Resistance was associated with elevated esterase levels, which cosegregated with resistance. In vitro studies employing surface plasmon resonance technology and other biochemical techniques demonstrated that resistant strain esterase could bind to Cry1Ac protoxin and activated toxin. In vivo studies showed that Cry1Ac-resistant larvae fed Cy1Ac transgenic cotton or Cry1Ac-treated artificial diet had lower esterase activity than non-Cry1Ac-fed larvae. A resistance mechanism in which esterase sequesters Cry1Ac is proposed.

scholarly journals Suppression of CD80 expression by ICP22 affect HSV-1 replication and CD8 + IFNγ + infiltrates in the eye of infected mice but not latency-reactivation

2021 ◽  
Author(s):  
Harry H. Matundan ◽  
Shaohui Wang ◽  
Ujjaldeep Jaggi ◽  
Jack Yu ◽  
Homayon Ghiasi
Keyword(s):  
T Cells ◽  
Virus Replication ◽  
Recombinant Virus ◽  
Costimulatory Molecule ◽  
Costimulatory Molecule Cd80 ◽  
Control Virus ◽  
The Impact ◽  
Hsv 1

Previously, we reported that HSV-1 ICP22 binds to the CD80 promoter and suppresses its expression in vitro and in vivo . To better understand the impact of ICP22 binding to CD80 on HSV-1 infectivity and pathogenicity, we mapped the region of ICP22 required to bind the CD80 promoter to a 40 aa region of ICP22. We constructed a recombinant HSV-1 expressing a truncated form of ICP22 that lacks these 40 aa, that does not bind to the CD80 promoter (KOS-ICP22Δ40) and retains the ability to replicate efficiently in rabbit skin cells, in contrast to ICP22-null virus. Replication of this recombinant virus in vitro and in vivo was higher than the ICP22-null virus but virus replication kinetics were lower than WT control virus. Similar to ICP22-null virus, the KOS-ICP22Δ40 mutant virus increased CD80 expression in DCs and IFNγ expression in CD8 + T cells but not CD4 + T cells in infected mouse corneas. In contrast to significantly reduced virus replication in the eyes of ocularly infected mice, levels of latency-reactivation were similar between KOS-ICP22Δ40 virus and WT virus. Thus, blocking ICP22 binding to the CD80 promoter using a recombinant virus expressing a truncated ICP22 that lacks CD80 promoter binding, appears to reduce virus replication and enhance CD8 + IFNγ + infiltrates in corneas of infected mice, with no effect on latency-reactivation. IMPORTANCE Direct binding of HSV-1 ICP22 to the CD80 promoter downregulates expression of the costimulatory molecule CD80, but not CD86. In this study we fine mapped the region of ICP22 required for binding to the CD80 promoter and constructed a recombinant virus containing a deletion in ICP22 that failed to bind to CD80 promoter. This recombinant virus replicated less efficiently in vitro and in vivo than did WT control virus although CD80-expressing CD11c + cells and IFNγ-expressing CD8 + T cells were increased. Interestingly, levels of latency and reactivation in the two viruses were similar, despite lower virus replication in the eyes of infected mice. Therefore, blocking the interaction of ICP22 to the CD80 promoter could be used to temper the immune response.

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