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Sosa-Gómez DR, Morgado FS, Corrêa RFT, Silva LA, Ardisson-Araújo DMP, Rodrigues BMP, Oliveira EE, Aguiar RWS, Ribeiro BM. Entomopathogenic Viruses in the Neotropics: Current Status and Recently Discovered Species. NEOTROPICAL ENTOMOLOGY 2020; 49:315-331. [PMID: 32358711 DOI: 10.1007/s13744-020-00770-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 03/03/2020] [Indexed: 06/11/2023]
Abstract
The market for biological control of insect pests in the world and in Brazil has grown in recent years due to the unwanted ecological and human health impacts of chemical insecticides. Therefore, research on biological control agents for pest management has also increased. For instance, insect viruses have been used to protect crops and forests around the world for decades. Among insect viruses, the baculoviruses are the most studied and used viral biocontrol agent. More than 700 species of insects have been found to be naturally infected by baculoviruses, with 90% isolated from lepidopteran insects. In this review, some basic aspects of baculovirus infection in vivo and in vitro infection, gene content, viral replication will be discussed. Furthermore, we provide examples of the use of insect viruses for biological pest control and recently characterized baculoviruses in Brazil.
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Affiliation(s)
- D R Sosa-Gómez
- Empresa Brasileira de Pesquisa Agropecuária, Embrapa Soja, Londrina, PR, Brasil
| | - F S Morgado
- Depto de Biologia Celular, Univ of Brasília, Brasília, DF, Brasil
| | - R F T Corrêa
- Depto de Biotecnologia, Univ Federal de Tocantins, Gurupi, TO, Brasil
| | - L A Silva
- Depto de Biologia Celular, Univ of Brasília, Brasília, DF, Brasil
| | - D M P Ardisson-Araújo
- Depto de Bioquímica e Biologia Molecular, Univ Federal de Santa Maria, Santa Maria, RS, Brasil
| | - B M P Rodrigues
- Depto de Biologia Celular, Univ of Brasília, Brasília, DF, Brasil
| | - E E Oliveira
- Depto de Entomologia, Univ Federal de Viçosa, Viçosa, MG, Brasil
| | - R W S Aguiar
- Depto de Biotecnologia, Univ Federal de Tocantins, Gurupi, TO, Brasil
| | - B M Ribeiro
- Depto de Biologia Celular, Univ of Brasília, Brasília, DF, Brasil.
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2
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Fabre ML, Masson T, Haase S, Ferrelli ML, Romanowski V. A simplified strategy to package foreign proteins into baculovirus occlusion bodies without engineering the viral genome. J Biotechnol 2020; 307:175-181. [PMID: 31715205 DOI: 10.1016/j.jbiotec.2019.10.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 10/08/2019] [Accepted: 10/26/2019] [Indexed: 11/25/2022]
Abstract
Polyhedron envelope protein (PEP) is the major component of the calyx that surrounds the baculovirus occlusion body (OB). PEP has been associated with the stabilization and resistance of polyhedra in the environment. Due to the abundant levels of PEP in OBs, we decided to use this protein as a fusion partner to redirect foreign proteins to baculovirus polyhedra. In this study we developed a strategy that involves the generation of a monoclonal transformed insect cell line expressing a protein of interest fused to the the Anticarsia gemmatalis multiple nucleopolyhedrovirus (AgMNPV) N-terminus of PEP that enables the packaging of foreign proteins into the OBs without generating a recombinant baculovirus. This proved to be an efficient platform that could be exploited to improve wild type baculovirus for their use as bioinsecticides without facing the concerns of releasing genetically modified DNA to the environment and bypassing the associated regulatory issues. We demonstrated, using immunological, proteomic and microscopy techniques, that the envelope of AgMNPV OBs can effectively trap chimeric proteins in an infected insect cell line expressing AgMNPV PEP fused to the enhanced green fluorescent protein (eGFP). Furthermore, packaging of chimeric PEP also took place with heterologous OBs such as those of Autographa californica multiple nucleopolyhedrovirus (AcMNPV), another group I alphabaculovirus.
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Affiliation(s)
- María Laura Fabre
- Instituto de Biotecnología y Biología Molecular (IBBM, UNLP-CONICET), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Buenos Aires, Argentina
| | - Tomás Masson
- Instituto de Biotecnología y Biología Molecular (IBBM, UNLP-CONICET), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Buenos Aires, Argentina
| | - Santiago Haase
- Instituto de Biotecnología y Biología Molecular (IBBM, UNLP-CONICET), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Buenos Aires, Argentina
| | - María Leticia Ferrelli
- Instituto de Biotecnología y Biología Molecular (IBBM, UNLP-CONICET), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Buenos Aires, Argentina
| | - Víctor Romanowski
- Instituto de Biotecnología y Biología Molecular (IBBM, UNLP-CONICET), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Buenos Aires, Argentina.
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3
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Morgado FDS, Ardisson-Araújo DMP, Ribeiro BM. Real-Time Expression Analysis of Selected Anticarsia gemmatalis multiple nucleopolyhedrovirus Gene Promoters during Infection of Permissive, Semipermissive and Nonpermissive Cell Lines. Viruses 2017; 9:E132. [PMID: 28587184 PMCID: PMC5490809 DOI: 10.3390/v9060132] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2017] [Revised: 05/22/2017] [Accepted: 05/24/2017] [Indexed: 12/03/2022] Open
Abstract
Baculovirus infection follows a transcriptionally controlled sequence of gene expression that occurs by activation of different viral gene promoter sequences during infection. This sequence of promoter activation may be disrupted by cellular defenses against viral infection, which might interfere with viral progeny formation. In this work, the activity of the ie1, gp64, lef-1, vp39, p6.9 and polh promoters of the Anticarsia gemmatalis multiple nucleopolyhedrovirus was assessed during infection of permissive, semipermissive and nonpermissive cell lines by a novel methodology that detects reporter protein luminescence in real-time. This technique allowed us to characterize in rich detail the AgMNPV promoters in permissive cell lines and revealed differential profiles of expression in cells with limited permissivity that correlate well with limitations in viral DNA replication. Semipermissive and nonpermissive cell lines presented delays and restrictions in late and very late promoter expression. Cells undergoing apoptosis did not inhibit late gene expression; however, viral progeny formation is severely affected. This work demonstrates the application of the real-time luminescence detection methodology and how the promoter expression profile may be used to diagnose cellular permissivity to baculovirus infection.
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Affiliation(s)
- Fabricio da Silva Morgado
- Laboratory of Baculovirus, Cell Biology Department, University of Brasília, 70910-900 Brasília-DF, Brazil.
| | - Daniel Mendes Pereira Ardisson-Araújo
- Laboratory of Insect Virology, Department of Biochemistry and Molecular Biology, Federal University of Santa Maria, 97105-900 Santa Maria-RS, Brazil.
| | - Bergmann Morais Ribeiro
- Laboratory of Baculovirus, Cell Biology Department, University of Brasília, 70910-900 Brasília-DF, Brazil.
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4
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Micheloud GA, Gioria VV, Eberhardt I, Visnovsky G, Claus JD. Production of the Anticarsia gemmatalis multiple nucleopolyhedrovirus in serum-free suspension cultures of the saUFL-AG-286 cell line in stirred reactor and airlift reactor. J Virol Methods 2011; 178:106-16. [PMID: 21906626 DOI: 10.1016/j.jviromet.2011.08.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2011] [Accepted: 08/14/2011] [Indexed: 10/17/2022]
Abstract
The velvetbean caterpillar, Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae), is one of the main plagues for soybean crops. Velvetbean caterpillar larvae are susceptible to be infected by occlusion bodies of the baculovirus Anticarsia gemmatalis multiple nucleopolyhedrovirus (AgMNPV), a biological insecticide. The insect cell line saUFL-AG-286 produces very high yields of occlusion bodies of AgMNPV in suspension cultures done in the low-cost serum-free medium UNL-10 in shake-flasks. However, its ability to adapt to conditions of industrial production in bioreactors was unknown. The aim of this study was to characterize the growth of saUFL-AG-286 cell cultures in UNL-10 medium, as well as its capability to replicate AgMNPV in two different bio-reactors at laboratory scale. The cell line was able to adapt to conditions that can be used at industrial scale, both in an airlift reactor and a stirred reactor, although the former was better than the last to support the cell growth. The infection with AgMNPV in the airlift reactor produced a high yield of occlusion bodies, with very low production of budded virus, the progeny used as inoculums. On the other hand, infection in the stirred reactor yielded high titers of budded virus. These results suggest that a feasible strategy for scaling-up the production of AgMNPV might involve the use of airlift reactors for the scaling-up of cell suspension cultures and the final production of occlusion bodies, while the scaling-up of the viral inoculums being carried out under conditions as those existing in stirred reactors.
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Affiliation(s)
- Gabriela A Micheloud
- Laboratorio de Virología, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Santa Fe, Argentina
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5
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da Silveira EB, Cordeiro BA, Ribeiro BM, de Castro MEB, Soares EF, Báo SN. An Anticarsia gemmatalis multiple nucleopolyhedrovirus mutant, vApAg, induces hemocytes apoptosis in vivo and displays reduced infectivity in larvae of Anticarsia gemmatalis (Hübner) (Lepidoptera: Noctuidae). Virus Res 2007; 130:182-92. [PMID: 17643541 DOI: 10.1016/j.virusres.2007.06.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2007] [Revised: 06/04/2007] [Accepted: 06/11/2007] [Indexed: 10/23/2022]
Abstract
An Anticarsia gemmatalis multiple nucleopolyhedrovirus (AgMNPV) mutant, vApAg, induces apoptosis in a cell culture derived from Anticarsia gemmatalis (UFL-AG-286), reducing viral progeny. We have investigated apoptosis induction in vivo by vApAg in A. gemmatalis larvae and its correlation to infectivity reduction. LC(50), LD(50), LT(50) and the mean time to death of larvae were determined for vApAg and AgMNPV. Apoptosis was accessed for hemocytes of infected larvae using light and transmission electron microscopy. All types of hemocytes can be infected by vApAg. After 12h post-infection (h p.i.), typical cellular modifications associated to nucleopolyhedrovirus infection were observed. Apoptosis becomes evident after 24h p.i., and massive after 72h p.i. Necrosis of infected cells was also observed. Despite cell death, hemocytes produced budded viruses and polyhedra. Pl and gh1-type hemocytes presented phagocytic activity. Agarose gel electrophoresis revealed fragmentation of hemocytes DNA at late times post-infection. The LC(50) and LD(50) were between five- and six-fold higher for vApAg. The LT(50) and the mean time to death were higher for vApAg in a same treatment or for a similar mortality induced by AgMNPV. These results show correlation of apoptosis and the reduced infectivity of vApAg in A. gemmatalis larvae.
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Affiliation(s)
- Eni Braga da Silveira
- Departamento de Biologia Celular, Instituto de Ciências Biológicas, Universidade Estadual de Campinas, C.P. 6109, Campinas 13083-863, SP, Brazil
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6
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Oliveira JVDC, Wolff JLC, Garcia-Maruniak A, Ribeiro BM, de Castro MEB, de Souza ML, Moscardi F, Maruniak JE, Zanotto PMDA. Genome of the most widely used viral biopesticide: Anticarsia gemmatalis multiple nucleopolyhedrovirus. J Gen Virol 2006; 87:3233-3250. [PMID: 17030857 DOI: 10.1099/vir.0.82161-0] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The genome of Anticarsia gemmatalis multiple nucleopolyhedrovirus isolate 2D (AgMNPV-2D), which is the most extensively used virus pesticide in the world, was completely sequenced and shown to have 132 239 bp (G+C content 44.5 mol%) and to be capable of encoding 152 non-overlapping open reading frames (ORFs). Three ORFs were unique to AgMNPV-2D, one of which (ag31) had similarity to eukaryotic poly(ADP-ribose) polymerases. The lack of chiA and v-cath may explain some of the success and growth of the AgMNPV biological control programme, as it may explain the high recovery of polyhedra sequestered inside dead larvae in the field, which are collected and used for further application as biological pesticides in soybean fields. The genome organization was similar to that of the Choristoneura fumiferana defective MNPV (CfDefNPV). Most of the variation between the two genomes took place near highly repetitive regions, which were also closely associated with bro-coding regions. The separation of the NPVs into groups I and II was supported by: (i) a phenogram of the complete genomes of 28 baculovirus and Heliothis zea virus 1, (ii) the most parsimonious reconstruction of gene content along the phenograms and (iii) comparisons of genomic features. Moreover, these data also reinforced the notion that group I of the NPVs can be split further into the AgMNPV lineage (AgMNPV, CfDefNPV, Epiphyas postvittana NPV, Orgyia pseudotsugata MNPV and C. fumiferana MNPV), sharing eight defining genes, and the Autographa californica MNPV (AcMNPV) lineage (AcMNPV, Rachiplusia ou NPV and Bombyx mori NPV), sharing nine defining genes.
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Affiliation(s)
- Juliana Velasco de Castro Oliveira
- Laboratório de Evolução Molecular e Bionformática, Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, SP, Brazil
| | - José Luiz Caldas Wolff
- Laboratório de Virologia Molecular, Núcleo Integrado de Biotecnologia, Universidade de Mogi das Cruzes, Mogi das Cruzes, SP, Brazil
| | - Alejandra Garcia-Maruniak
- Entomology and Nematology Department, PO Box 110620, University of Florida, Gainesville, FL 32611-0620, USA
| | | | | | - Marlinda Lobo de Souza
- Embrapa Recursos Genéticos e Biotecnologia-Núcleo Temático de Controle Biológico (NTCB), Brasília, DF, Brazil
| | | | - James Edward Maruniak
- Entomology and Nematology Department, PO Box 110620, University of Florida, Gainesville, FL 32611-0620, USA
| | - Paolo Marinho de Andrade Zanotto
- Laboratório de Evolução Molecular e Bionformática, Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, SP, Brazil
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7
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Soares JS, Ribeiro BM. Pathology of Anticarsia gemmatalis larvae infected by two recombinant A. gemmatalis multicapsid nucleopolyhedroviruses. Res Microbiol 2005; 156:263-9. [PMID: 15748993 DOI: 10.1016/j.resmic.2004.09.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2004] [Revised: 09/11/2004] [Accepted: 09/13/2004] [Indexed: 11/25/2022]
Abstract
Light and stereomicroscopy examinations of Anticarsia gemmatalis multicapsid nucleopolyhedrovirus (AgMNPV)-infected insects were performed in order to follow infection in its host, A. gemmatalis. Fourth-instar A. gemmatalis larvae were infected by administration of occluded virus (polyhedra) from two recombinant AgMNPV viruses (vAgEGTDelta-lacZ or vAgGalA2) directly into the larvae foregut. The recombinant virus vAgEGTDelta-lacZ has the beta-galactosidase gene (lac-Z) of Escherichia coli under the control of a constitutive promoter (hsp70 from Drosophila melanogaster). The vAgGalA2 virus has the reporter gene lac-Z under the control of the AgMNPV very late polyhedrin gene promoter. At different times post-infection (p.i.) the infected larvae were dissected, fixed, and the product of the expression of the lac-Z gene detected by incubating the insects in a buffer containing X-gal. This allowed us to follow the infection through the blue cells (due to the degradation of X-gal by the enzyme Lac-Z). Insect larvae inoculated with polyhedra from the recombinant viruses showed midgut cells to be infected first, followed by tracheal cells, hemolymph, fat body, Malpighian tubules and brain cells. The infection was similar for the two recombinant viruses, with blue cells appearing earlier in insects infected with the vAgEGTDelta-lacZ virus when compared to the vAgGalA2 virus.
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Affiliation(s)
- José S Soares
- Laboratory of Electron Microscopy and Virology, University of Brasília, Brasília, DF, CEP 70910-900, Brazil
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8
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Silveira EB, Cordeiro BA, Ribeiro BM, Báo SN. Morphological characterization of Anticarsia gemmatalis M nucleopolyhedrovirus infection in haemocytes from its natural larval host, the velvet bean caterpillar Anticarsia gemmatalis (Hübner) (Lepidoptera: Noctuidae). Tissue Cell 2004; 36:171-80. [PMID: 15140594 DOI: 10.1016/j.tice.2004.01.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2003] [Revised: 01/08/2004] [Accepted: 01/09/2004] [Indexed: 11/16/2022]
Abstract
For a better understanding of virus x host interactions, transmission electron microscopy was used to characterize the intrahaemocoelic infection of Anticarsia gemmatalis larval haemocytes by A. gemmatalis M nucleopolyhedrovirus (AgMNPV). At 12 h post-infection (h p.i.), we observed nuclear hypertrophy, budded virus assembling, and protrusion towards the cytoplasm, virion envelopment, and accumulation of fibrillar aggregates in the cytoplasm. Around 24 h p.i., fibrillar aggregates also appeared inside nuclei of infected cells. By 48 h p.i., virogenic stroma and polyhedra were visualised in nuclei and at 72 h p.i., widespread infection in haemocytes was observed. Cell remnants and free polyhedra were phagocytosed by granular haemocyte 1 and plasmatocytes. Entire cells were phagocytosed only by plasmatocytes. Necrosis of infected cells was quite common, suggesting a putative cytotoxic response. Granular haemocyte 1 presented a more exuberant protrusion of budded viruses in comparison to other haemocytes. All types of haemocytes were shown to be infected, and the intense virus replication in some of these cells reveals the importance of haemolymph for AgMNPV spread in its natural host, a critical factor for permissiveness.
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Affiliation(s)
- E B Silveira
- Departamento de Biologia Celular, Instituto de Ciências Biológicas, Universidade Estudual de Campinas, Campinas, SP, Brazil
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9
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Razuck FB, Ribeiro B, Vargas JH, Wolff JL, Ribeiro BM. Characterization of the p10 gene region of Anticarsia gemmatalis nucleopolyhedrovirus. Virus Genes 2002; 24:243-7. [PMID: 12086145 DOI: 10.1023/a:1015328516018] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The Anticarsia gemmatalis nucleopolyhedrovirus (AgMNPV) p10 gene region was cloned, sequenced and the putative p10 gene expression characterized by Northern-blot analysis. Sequence analysis of the p10 gene region indicated the presence of two complete open reading frames (ORFs) of 713 and 281 nucleotides, which codes for polypeptides of 273 and 93 amino acids, with homology to the P26 and P10 proteins of baculoviruses, respectively. Two additional partial ORFs, coding for partial polypeptides of 110 and 146 amino acids, showed homology to the p22.2 gene of Choristoneura fumiferana nucleopolyhedrovirus (CfMNPV) and p74 genes of different baculoviruses, respectively. A small ORF of 224 nucleotides coding for a protein of 74 amino acids showed homology to the 3'-end of the early p94 gene of AcMNPV. A putative baculovirus very late promoter motif TAAG was identified in the 5'-non-translated region (5'-UTR) at position-54 upstream of the start codon. The consensus polyadenylation sequence AATAAA is present 146nt downstream of the termination codon and the p10 ORF is flanked by the p26 and p74 ORFs. Homology comparisons showed that the P10 protein of AgMNPV is most closely related (82% amino acid sequence identity) to the P10 from the Orgyia pseudotsugata nucleopolyhedrovirus (OpMNPV). Transcriptional analysis of the AgMNPV p10 gene showed that p10-specific transcripts could be detected late in infection.
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10
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de Castro ME, Ribeiro BM. Production of viral progeny in insect cells undergoing apoptosis induced by a mutant Anticarsia gemmatalis nucleopolyhedrovirus. Microbiol Res 2002; 156:369-76. [PMID: 11770855 DOI: 10.1078/0944-5013-00122] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The Anticarsia gemmatalis nucleopolyhedrovirus (AgMNPV) is the most successful viral biopesticide in use worldwide. We have demonstrated that despite widespread apoptosis and no protein synthesis at 48 h p.i., UFL-AG-286 cells infected with a mutant of AgMNPV (vApAg), produced significant amounts of budded virus (BVs) and viral DNA late in infection. However, a different susceptible cell line (BTI-Tn5B 1-4) showed no signs of apoptosis and produced 3.5 times more budded virus when infected with vApAg. A comparison of DNA from AgMNPV and vApAg digested with the same restriction enzymes showed differences in the restriction pattern, indicating that the vApAg phenotype might be due to a mutation in a gene or genes responsible for directly or indirectly inhibiting apoptosis in UFL-AG-286 cells.
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Affiliation(s)
- M E de Castro
- Embrapa Recursos Genéticos e Biotecnologia, Cx. Postal 02372, Brasília, DF, 70849-970, Brasil
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11
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Rodrigues JC, De Souza ML, O'Reilly D, Velloso LM, Pinedo FJ, Razuck FB, Ribeiro B, Ribeiro BM. Characterization of the ecdysteroid UDP-glucosyltransferase (egt) gene of Anticarsia gemmatalis nucleopolyhedrovirus. Virus Genes 2001; 22:103-12. [PMID: 11210933 DOI: 10.1023/a:1008142621359] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The Anticarsia gemmatalis nucelopolyhedrovirus (AgMNPV) egt gene was cloned, sequenced and its expression characterized by RT-PCR and western blot analysis. Sequence analysis of the gene indicated the presence of an open reading frame (ORF) of 1482 nucleotides, which codes for a polypeptide of 494 amino acids. ATATA box and a conserved regulatory sequence (CATT) found in other baculovirus early genes were present in the promoter region of the egt gene. A poly-A consensus sequence was present in the 3' untranslated region (3'-UTR) of the gene. Homology comparisons showed that the EGT protein of AgMNPV is most closely related (95.9% amino acid sequence identity) to the EGT from the Choristoneura fumiferana DEF nucleopolyhedrovirus (CfDEF). Transcriptional analysis of the AgMNPV egt gene showed that egt-specific transcripts can be detected both early and late in infection. The EGT protein was detected, by western blot analysis, in the intra- (from 12 to 48 h post-infection) and extra-cellular (from 12 to 96 h post-infection) fractions of infected insect cells. The AgMNPV Bgl II-F fragment, which has homology to the AcMNPV ie-1 gene, was cloned and used to cotransfect SF21 cells with the cloned AgMNPV egt gene. EGT activity was observed, suggesting that AgMNPV ie-1 can transactivate egt expression.
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Affiliation(s)
- J C Rodrigues
- Embrapa Genetic Resources and Biotechnology, Brasília, Brasil.
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12
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Matos TG, Giugliano LG, Ribeiro BM, Báo SN. Structural and ultrastructural studies of Anticarsia gemmatalis midgut cells infected with the baculovirus A. gemmatalis nucleopolyhedrovirus. ACTA ACUST UNITED AC 1999. [DOI: 10.1016/s0020-7322(99)00024-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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