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Akhanaev YB, Pavlushin SV, Kharlamova DD, Odnoprienko D, Subbotina AO, Belousova IA, Ignatieva AN, Kononchuk AG, Tokarev YS, Martemyanov VV. The Impact of a Cypovirus on Parental and Filial Generations of Lymantria dispar L. INSECTS 2023; 14:917. [PMID: 38132591 PMCID: PMC10743831 DOI: 10.3390/insects14120917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 11/29/2023] [Accepted: 11/29/2023] [Indexed: 12/23/2023]
Abstract
Recently, we found that the spongy moth Lymantria dispar L. is susceptible to infection by a Dendrolimus sibiricus cytoplasmic polyhedrosis virus (DsCPV-1). In the present study, we evaluated the pathogenicity of DsCPV-1 against L. dispar larvae and its impact on surviving insects after the infection. Offspring of virally challenged insects were tested for susceptibility to a stress factor (starvation). In addition, we used light microscopy and quantitative polymerase chain reaction (qPCR) to test the ability of DsCPV-1 to be transmitted vertically. We found insect mortality of the L. dispar parents following the infection was positively associated with DsCPV-1 dose. DsCPV-1 was lethal to second-instar L. dispar larvae with a 50% lethal dose (LD50) of 1687 occlusion bodies per larva. No vertical transmission of DsCPV-1 to offspring larvae was detected, while the majority of insect deaths among offspring larvae were caused by microsporidia (Vairimorpha lymantriae), which was harbored by the parents. The offspring of virally challenged parents exhibited a higher number of detected microsporidia compared to the control. Our findings suggest that the application of DsCPV-1 is effective in controlling pests in terms of transgenerational impact following virus exposure.
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Affiliation(s)
- Yuriy B. Akhanaev
- Institute of Systematics and Ecology of Animals, SB RAS, Frunze Str. 11, Novosibirsk 630091, Russia
| | - Sergey V. Pavlushin
- Institute of Systematics and Ecology of Animals, SB RAS, Frunze Str. 11, Novosibirsk 630091, Russia
| | - Daria D. Kharlamova
- Institute of Systematics and Ecology of Animals, SB RAS, Frunze Str. 11, Novosibirsk 630091, Russia
- Institute of Biology, Irkutsk State University, Karl Marx Str. 1, Irkutsk 664003, Russia
| | - Daria Odnoprienko
- Department of Molecular Biology and Biotechnology, Novosibirsk State University, Pirogova Str. 1, Novosibirsk 630090, Russia
| | - Anna O. Subbotina
- Institute of Systematics and Ecology of Animals, SB RAS, Frunze Str. 11, Novosibirsk 630091, Russia
- Department of Molecular Biology and Biotechnology, Novosibirsk State University, Pirogova Str. 1, Novosibirsk 630090, Russia
| | - Irina A. Belousova
- Institute of Systematics and Ecology of Animals, SB RAS, Frunze Str. 11, Novosibirsk 630091, Russia
| | - Anastasia N. Ignatieva
- All-Russian Institute of Plant Protection, Sch. Podbelskogo 3, Pushkin, St. Petersburg 196608, Russia
| | - Anastasia G. Kononchuk
- All-Russian Institute of Plant Protection, Sch. Podbelskogo 3, Pushkin, St. Petersburg 196608, Russia
| | - Yuri S. Tokarev
- All-Russian Institute of Plant Protection, Sch. Podbelskogo 3, Pushkin, St. Petersburg 196608, Russia
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2
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Xu C, Wang J, Yang J, Lei C, Hu J, Sun X. NSP2 forms viroplasms during Dendrolimus punctatus cypovirus infection. Virology 2019; 533:68-76. [PMID: 31125854 DOI: 10.1016/j.virol.2019.05.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 05/14/2019] [Accepted: 05/15/2019] [Indexed: 10/26/2022]
Abstract
Reoviruses are thought to replicate and assemble in special cytoplasmic structures called 'viroplasms'. However, little is known about the viroplasms of the insect reoviruses, the cypoviruses. To investigate the viroplasm of Dendrolimus punctatus cypovirus (DpCPV), all proteins encoded by the 10 genomic segments of DpCPV were expressed in Sf9 cells using the Bac-to-Bac system. The viral nonstructural protein NSP2 formed viroplasm-like dots which showed close apposition with the endoplasmic reticulum and were surrounded by intracellular membranes during transfection. Colocalization and coimmunoprecipitation assays showed that NSP2 interacts with 4 of 6 structural proteins and another 2 nonstructural proteins, while NSP1 only colocalized with VP4, and NSP3 did not colocalize with any structural protein. Immunoelectron microscopy revealed that NSP2 were nearby the endoplasmic reticulum and mitochondria, and viral particles were present in the electron-dense inclusions formed by NSP2. We proposed that NSP2 is responsible for forming the viroplasms structures of DpCPV.
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Affiliation(s)
- Congrui Xu
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, Hubei, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jia Wang
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, Hubei, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jian Yang
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, Hubei, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Chengfeng Lei
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, Hubei, China
| | - Jia Hu
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, Hubei, China
| | - Xiulian Sun
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, Hubei, China.
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3
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Cell-line-dependent crystal morphology and sublocalization of the Thyrinteina arnobia cypovirus polyhedrin expressed from a recombinant baculovirus. Arch Virol 2019; 164:1677-1682. [DOI: 10.1007/s00705-019-04214-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 02/21/2019] [Indexed: 01/30/2023]
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4
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Kemp EM, Woodward DT, Cory JS. Detection of single and mixed covert baculovirus infections in eastern spruce budworm, Choristoneura fumiferana populations. J Invertebr Pathol 2011; 107:202-5. [DOI: 10.1016/j.jip.2011.05.015] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2011] [Revised: 05/09/2011] [Accepted: 05/09/2011] [Indexed: 12/01/2022]
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5
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Molecular characterisation of a cypovirus isolated from the western spruce budworm Choristoneura occidentalis. Arch Virol 2008; 153:1759-63. [PMID: 18695934 DOI: 10.1007/s00705-008-0175-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2008] [Accepted: 07/21/2008] [Indexed: 10/21/2022]
Abstract
A novel cypovirus, assigned CoCPV, was isolated from natural populations of the western spruce budworm, Choristoneura occidentalis. The complete nucleotide sequences of genomic segments S2-S5 and S7-S10 were determined. Each segment contained a single open reading frame. Conserved motifs 5' (AGUUU......UUUGUGC) 3' were found at the ends of each segment. Analysis of S2, which encoded a putative RNA-dependent RNA polymerase protein, confirmed CoCPV belonged to the genus Cypovirus within the family Reoviridae. Further phylogenetic analysis using S10 (the polyhedrin gene) aligned this virus with species type-16, closely related to a cypovirus isolated from C. fumiferana.
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6
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Graham RI, Rao S, Sait SM, Attoui H, Mertens PPC, Hails RS, Possee RD. Sequence analysis of a reovirus isolated from the winter moth Operophtera brumata (Lepidoptera: Geometridae) and its parasitoid wasp Phobocampe tempestiva (Hymenoptera: Ichneumonidae). Virus Res 2008; 135:42-7. [PMID: 18405997 PMCID: PMC7114361 DOI: 10.1016/j.virusres.2008.02.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2007] [Revised: 02/13/2008] [Accepted: 02/15/2008] [Indexed: 11/29/2022]
Abstract
A reovirus was isolated from Operophtera brumata (ObRV) and its parasitoid wasp Phobocampe tempestiva. Each of the 10 dsRNA genome segments of ObRV was sequenced and shown to contain a single open reading frame (ORF). Conserved motifs ([+ve] 5'-AAATAAA ...(G)/(T)AGGTT-3') were found at the termini of each segment, with the exception of Seg-6 and Seg-8, where the 5' termini were 5'-AACAAA...-3'. The putative proteins encoded by each segment were compared with those of other members of the family Reoviridae. Phylogenetic comparisons to published sequences for the RNA-dependent RNA polymerase genes from other reoviruses indicated that ObRV is most closely related to members of the genus Cypovirus. However, unlike the cypoviruses, ObRV has a double-layered capsid structure. When the protein encoded by ObRV Seg-10 was expressed (by inserting the open reading frame into a baculovirus expression vector) no 'occlusion bodies' were observed in the recombinant baculovirus infected insect cell cultures. This suggests that unlike the cypoviruses, Seg-10 of ObRV does not contain a polyhedrin gene. Further phylogenetic comparisons also identified relationships between Seg-2 and Seg-10 of ObRV, and genes of Diadromus pulchellus Idnoreovirus 1 (DpIRV1), suggesting that ObRV represents a new species from the genus Idnoreovirus.
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Affiliation(s)
- Robert I Graham
- NERC Centre for Ecology and Hydrology, Mansfield Road, Oxford OX1 3SR, UK.
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7
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Graham RI, Rao S, Sait SM, Mertens PPC, Hails RS, Possee RD. Characterisation and partial sequence analysis of two novel cypoviruses isolated from the winter moth Operophtera brumata (Lepidoptera: Geometridae). Virus Genes 2007; 35:463-71. [PMID: 17546493 DOI: 10.1007/s11262-007-0113-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2007] [Accepted: 05/04/2007] [Indexed: 11/28/2022]
Abstract
The complete nucleotide sequences of genomic segments S5 to S10 from Operophtera brumata cypovirus 18 (OpbuCPV18), and the complete nucleotide sequences of genomic segments S2, S5, S9 and S10 from Operophtera brumata cypovirus 19 (OpbuCPV19) have been determined. Each genome segment contained a single open reading frame (ORF). Conserved motifs 5' (AGUAAA....GUUAGCU) 3' were found at the ends of each segment of OpbuCPV18, whilst conserved motifs 5' (AACAAA....UUUGC) 3' were found at each segment terminus of OpbuCPV19. The putative proteins were compared with those of other members of the Reoviridae family. Phylogenetic analysis using the polyhedrin gene (S10) indicated that OpbuCPV18 was most closely related to Dendrolimus punctatus cypovirus 1, whilst OpbuCPV19 was most closely related to Trichoplusia ni cypovirus 15. In addition, analysis of S2, which encoded a putative RNA-dependant RNA polymerase gene, confirmed OpbuCPV19 belonged to the genus Cypovirus. Following the expression of the ORF from OpbuCPV19 S10, using a baculovirus expression vector, occlusion bodies were observed in insect cell culture. This demonstrated that segment 10 coded for the polyhedrin gene, capable of forming a polyhedral crystalline matrix.
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Affiliation(s)
- Robert I Graham
- NERC Centre for Ecology and Hydrology, Mansfield Rd., Oxford, OX1 3SR, UK
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8
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Green TB, White S, Rao S, Mertens PPC, Adler PH, Becnel JJ. Biological and molecular studies of a cypovirus from the black fly Simulium ubiquitum (Diptera: Simuliidae). J Invertebr Pathol 2007; 95:26-32. [PMID: 17224161 DOI: 10.1016/j.jip.2006.10.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2006] [Revised: 10/05/2006] [Accepted: 10/24/2006] [Indexed: 11/29/2022]
Abstract
A cypovirus from the black fly Simulium ubiquitum (SuCPV) was isolated and examined using biological and molecular techniques. SuCPV produces small (typically 0.25mum), polyhedral shaped inclusion bodies (polyhedra), in which the virus particles become multiply embedded. SuCPV is the third cypovirus isolated from Diptera, but the first from Simuliidae that has been characterized using molecular analyses. SuCPV has a genome composed of 10 segments of dsRNA, with an electrophoretic migration pattern that is different from those of recent UsCPV-17 and CrCPV-17 isolates from the mosquitoes Uranotaenia sapphirina and Culex restuans, respectively. The SuCPV electropherotype appears to show significant differences from those of the previously characterized lepidopteran cypoviruses. Sequence analysis of SuCPV segment 10 shows that it is unrelated to either of the two CPV isolates from Diptera or to the CPV species for which Seg-10 has been previously characterized from Lepidoptera. A comparison of the terminal regions of SuCPV genome segments to those of CPV-1, 2, 4, 5 14, 15, 16, 17, 18, and 19 also revealed only low levels of conservation. We therefore, propose that SuCPV is classified within a new Cypovirus species, which we have tentatively identified as Cypovirus-20. We have therefore referred to this virus isolate as S. ubiquitum CPV-20 (SuCPV-20).
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Affiliation(s)
- Terry B Green
- ARS, CMAVE, 1600-1700 S.W. 23rd Drive, Gainesville, FL 32608, USA
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9
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Chavali VRM, Ghosh AK. Molecular cloning, sequence analysis and expression of genome segment 7 (S7) of Antheraea mylitta cypovirus (AmCPV) that encodes a viral structural protein. Virus Genes 2007; 35:433-41. [PMID: 17253125 DOI: 10.1007/s11262-006-0070-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2006] [Accepted: 08/07/2006] [Indexed: 10/23/2022]
Abstract
The Genome segment 7 (S7) of the 11 double stranded RNA genomes from Antheraea mylitta cypovirus (AmCPV) was converted to cDNA, cloned and sequenced. The nucleotide sequence showed that segment 7 consisted of 1789 nucleotides with an ORF of 530 amino acids and could encode a protein of approximately 61 kDa, termed P61. The 5' terminal sequence, AGTAAT and the 3' terminal sequence, AGAGC of the plus strand was found to be the same as genome segment 10 of AmCPV encoding polyhedrin. No sequence similarity was found by searching nucleic acid and protein sequence databases using BLAST. The secondary structure prediction showed the presence of 17 alpha-helices, 18 extended beta-sheets along the entire length of P61. The ORF of segment 7 was expressed in E. coli as His-tagged fusion protein, purified through Ni-NTA chromatography, and polyclonal antibody was raised in rabbit indicating that P61 is immunogenic. Immunoblot analysis using this antibody on viral infected cells as well as purified polyhedra showed that P61 is a viral structural protein. Motif scan search showed some similarity of P61 with Inosine monophosphate dehydrogenase (IMPDH) cystathionine-beta-synthase (CBS) domain at the C-terminus and it was hypothesized that by binding to single stranded viral RNA through its CBS domain P61 may help in virus replication or transcription.
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10
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Zhao SL, Liang CY, Zhang WJ, Tang XC, Peng HY. Characterization of the RNA-binding domain in the Dendrolimus punctatus cytoplasmic polyhedrosis virus nonstructural protein p44. Virus Res 2005; 114:80-8. [PMID: 16023751 DOI: 10.1016/j.virusres.2005.06.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2005] [Revised: 06/01/2005] [Accepted: 06/06/2005] [Indexed: 11/24/2022]
Abstract
Dendrolimus punctatus cytoplasmic polyhedrosis virus (DpCPV-1) belongs to the Cypovirus genus in the Reoviridae family. The ORF of genome segment 8 (S8) of DpCPV-1 was cloned into vector pMAL-c2X and used to express a 44kDa protein (p44) in E. coli, which was detected by Western blotting. The gel mobility shift assays showed that p44 had ssRNA-binding activity. Competitive assay indicated that this protein only bind to ssRNA and could not interact with DNA and dsRNA. The binding of p44 to ssRNA is sequence non-specific. To identify the domain(s) important for RNA binding of the protein, a number of deletions were made. These truncated proteins were expressed in E. coli and purified. The affinity of each truncated protein towards ssRNA was then assayed by electrophoretic mobility shift assays and northwestern blot. The results indicated that glutamic acid-rich domain in the central region of p44 from residues 104 to 201 was the ssRNA-binding domain.
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Affiliation(s)
- S L Zhao
- Laboratory for Biological Control, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China.
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11
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Shapiro A, Green T, Rao S, White S, Carner G, Mertens PPC, Becnel JJ. Morphological and molecular characterization of a Cypovirus (Reoviridae) from the mosquito Uranotaenia sapphirina (Diptera: Culicidae). J Virol 2005; 79:9430-8. [PMID: 16014906 PMCID: PMC1181557 DOI: 10.1128/jvi.79.15.9430-9438.2005] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A novel cypovirus has been isolated from the mosquito Uranotaenia sapphirina (UsCPV) and shown to cause a chronic infection confined to the cytoplasm of epithelial cells of the gastric ceca and posterior stomach. The production of large numbers of virions and inclusion bodies and their arrangement into paracrystalline arrays gives the gut of infected insects a distinctive blue iridescence. The virions, which were examined by electron microscopy, are icosahedral (55 to 65 nm in diameter) with a central core that is surrounded by a single capsid layer. They are usually packaged individually within cubic inclusion bodies (polyhedra, approximately 100 nm across), although two to eight virus particles were sometimes occluded together. The virus was experimentally transmitted per os to several mosquito species. The transmission rate was enhanced by the presence of magnesium ions but was inhibited by calcium ions. Most of the infected larvae survived to adulthood, and the adults retained the infection. Electrophoretic analysis of the UsCPV genome segments (using 1% agarose gels) generated a migration pattern (electropherotype) that is different from those of the 16 Cypovirus species already recognized. UsCPV genome segment 10 (Seg-10) showed no significant nucleotide sequence similarity to the corresponding segment of the other cypoviruses that have previously been analyzed, and it has different "conserved" termini. A BLAST search of the UsCPV deduced amino acid sequence also showed little similarity to Antheraea mylitta CPV-4 (67 of 290 [23%]) or Choristoneura fumiferana CPV-16 (33 of 111 [29%]). We conclude that UsCPV should be recognized as a member of a new Cypovirus species (Cypovirus 17, strain UsCPV-17).
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Affiliation(s)
- Alexandra Shapiro
- Center for Medical, Agricultural and Veterinary Entomology, USDA/ARS, Gainesville, FL 32604, USA
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12
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Sinha-Datta U, Chavali VRM, Ghosh AK. Molecular cloning and characterization of Antheraea mylitta cytoplasmic polyhedrosis virus polyhedrin gene and its variant forms. Biochem Biophys Res Commun 2005; 332:710-8. [PMID: 15907799 DOI: 10.1016/j.bbrc.2005.05.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2005] [Accepted: 05/05/2005] [Indexed: 11/23/2022]
Abstract
The segments 10 (S10) of the 11 double stranded RNA genomes from Antheraea mylitta cytoplasmic polyhedrosis virus (AmCPV) encoding a novel polyhedrin polypeptide was converted to cDNA, cloned, and sequenced. Three cDNA clones consisting of 1502 (AmCPV10-1), 1120 (AmCPV10-2), and 1415 (AmCPV10-3) nucleotides encoding polyhedrin of 254, 339, and 319 amino acids with molecular masses of 29, 39, and 37 kDa, respectively, were obtained, and verified by Northern analysis. These clones showed 70-94% sequence identity among them but none with any sequences in databases. The expression of AmCPV10-1 cDNA encoded polyhedrin in Sf-9 cells was detected by immunoblot analysis and formation of polyhedra by electron microscopy, as observed in AmCPV-infected gut cells, but no expression of AmCPV10-2 or AmCPV10-3 cDNA was detected, indicating that during AmCPV replication, along with functional S10 RNA, some defective variant forms of S10 RNAs are packaged in virion particles.
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Affiliation(s)
- Uma Sinha-Datta
- Department of Biotechnology, Indian Institute of Technology, Kharagpur 721302, India
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13
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Qanungo KR, Kundu SC, Mullins JI, Ghosh AK. Molecular cloning and characterization of Antheraea mylitta cytoplasmic polyhedrosis virus genome segment 9. J Gen Virol 2002; 83:1483-1491. [PMID: 12029164 DOI: 10.1099/0022-1317-83-6-1483] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Genome segment 9 of the 11-segment RNA genomes of three cytoplasmic polyhedrosis virus (CPV) isolates from Antheraea mylitta (AmCPV), Antheraea assamensis (AaCPV) and Antheraea proylei (ApCPV) were converted to cDNA, cloned and sequenced. In each case, this genome segment consists of 1473 nucleotides with one long ORF of 1035 bp and encodes a protein of 345 amino acids, termed NSP38, with a molecular mass of 38 kDa. Secondary structure prediction showed the presence of nine alpha-helices in the central and terminal domains with localized similarity to RNA-binding motifs of bluetongue virus and infectious bursal disease virus RNA polymerases. Nucleotide sequences were 99.6% identical between these three strains of CPVs, but no similarity was found to any other nucleotide or protein sequence in public databases. The ORF from AmCPV cDNA was expressed as a His-tagged fusion protein in E. coli and polyclonal antibody was raised against the purified protein. Immunoblot as well as immunofluorescence analysis with anti-NSP38 antibody showed that the protein was not present in polyhedra or uninfected cells but was present in AmCPV-infected host midgut cells. NSP38 was expressed in insect cells as soluble protein via a baculovirus expression vector and shown to possess the ability to bind poly(rI)-(rC) agarose, which was competitively removed by AmCPV viral RNA. These results indicate that NSP38 is expressed in virus-infected cells as a non-structural protein. By binding to viral RNA, it may play a role in the regulation of genomic RNA function and packaging.
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Affiliation(s)
- Kaustubha R Qanungo
- Department of Biotechnology, Indian Institute of Technology, Kharagpur 721302, India1
| | - Subhas C Kundu
- Department of Biotechnology, Indian Institute of Technology, Kharagpur 721302, India1
| | - James I Mullins
- Department of Microbiology, University of Washington, Seattle, WA 98195, USA2
| | - Ananta K Ghosh
- Department of Biotechnology, Indian Institute of Technology, Kharagpur 721302, India1
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14
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Hill CL, Booth TF, Stuart DI, Mertens PP. Lipofectin increases the specific activity of cypovirus particles for cultured insect cells. J Virol Methods 1999; 78:177-89. [PMID: 10204708 DOI: 10.1016/s0166-0934(98)00181-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cytoplasmic polyhedrosis viruses (CPV) are classified as 14 distinct species (electropherotypes) within the genus Cypovirus, family Reoviridae. Cypovirus research has been limited by a lack of appropriate cell culture systems (for each of these virus species) in which the majority of cells can become productively infected. Lipofection increased the infection rate of Lymantria dispar 652 cells, by virus particles (derived from polyhedra) of Orgyia pseudosugata type 5 cypovirus (Op-5 CPV), from 3 to 44%. Lipofection also significantly increased the percentage of Trichoplusia ni 368 cells infected with the same virus (from < 1 to approximately 7%). The spread of cypovirus infection between cells was either very slow or insignificant, and infected cells appeared to remain viable for long periods. Virus infection was detected by the observation of polyhedra formation in individual cells and it was therefore possible to develop a simple quantitative assay system to measure virus titre (TCID50). Cryo-electron microscopy showed that cypovirus particles formed a complex with the lipid, involving their envelopment within the liposome membrane. It was concluded that the increased infectivity of the virus by lipofection was due to a more efficient cell entry mechanism, probably involving fusion between liposome and cell membranes.
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Affiliation(s)
- C L Hill
- NERC Institute of Virology and Environmental Microbiology, Oxford, UK.
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15
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Hagiwara K, Tomita M, Kobayashi J, Miyajima S, Yoshimura T. Nucleotide sequence of Bombyx mori cytoplasmic polyhedrosis virus segment 8. Biochem Biophys Res Commun 1998; 247:549-53. [PMID: 9657006 DOI: 10.1016/s0006-291x(98)80004-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The segments 8 (S8) of the 10 double-stranded RNA genomes from Bombyx mori cytoplasmic polyhedrosis virus (BmCPV) strains I and H were converted into cDNAs, amplified by PCR, and cloned. The nucleotide sequence analysis of the two full-length S8 cDNAs showed that the segments consist of 1328 nucleotides encoding putative proteins (p44) of 390 amino acids with molecular masses of about 44 kDa, which have glutamic acid-rich and proline-rich domains in their central regions. They had quite high identity with each other: about 98% in nucleotide and amino acid sequences. The recombinant p44 expressed in BmN4 cells using the baculovirus vector was detected by immunoblot analysis. p44 was also confirmed with the same antiserum to be present in BmCPV-infected midgut cells, but not in polyhedra, virus virions and uninfected midgut cells, indicating that p44 is expressed as a nonstructural protein of BmCPV.
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Affiliation(s)
- K Hagiwara
- Department of Chemistry for Materials, Faculty of Engineering, Mie University, Japan
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