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Mikhailov VS, Rohrmann GF. Binding of the baculovirus very late expression factor 1 (VLF-1) to different DNA structures. BMC Mol Biol 2002; 3:14. [PMID: 12350233 PMCID: PMC130038 DOI: 10.1186/1471-2199-3-14] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2002] [Accepted: 09/26/2002] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Baculovirus genomes encode a gene called very late expression factor 1 (VLF-1) that is a member of the integrase (Int) family of proteins. In this report we describe the binding properties of purified Autographa californica multiple capsid nucleopolyhedrovirus (AcMNPV) VLF-1 to a number of different DNA structures including homologous regions. In addition, its enzymatic activity was examined. RESULTS VLF-1 was expressed in a recombinant baculovirus as a fusion with both HA and HIS6 tags and its binding activity to different DNA structures was tested. No binding was evident to single and double strand structures, very low binding was observed to Y-forks, more binding was observed to three-way junctions, whereas cruciform structures showed high levels of binding. VLF-1 binding was affected by divalent cations; optimal binding to three-way junctions and cruciforms was 2 and 0 mM MgCl2, respectively. Homologous region (hr) sequences was also examined including oligomers designed to expose the hr palindrome as a hairpin, linear double strand, or H-shaped structure. Efficient binding was observed to the hairpin and H-shaped structure. No topoisomerase or endonuclease activity was detected. Sedimentation analysis indicated that *VLF-1 is present as a monomer. CONCLUSIONS An HA- and HIS-tagged version of AcMNPV VLF-1 showed structure-dependent binding to DNA substrates with the highest binding affinity to cruciform DNA. These results are consistent with the involvement of VLF-1 in the processing of branched DNA molecules at the late stages of viral genome replication. We were unable to detect enzymatic activity associated with these complexes.
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Affiliation(s)
- Victor S Mikhailov
- Department of Microbiology, Oregon State University, Corvallis, Oregon 97331-3804, USA
- N. K. Koltzov Institute of Developmental Biology, Russian Academy of Sciences, Moscow 117808, Russia
| | - George F Rohrmann
- Department of Microbiology, Oregon State University, Corvallis, Oregon 97331-3804, USA
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202
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Jehle JA. The expansion of a hypervariable, non-hr ori-like region in the genome of Cryptophlebia leucotreta granulovirus provides in vivo evidence for the utilization of baculovirus non-hr oris during replication. J Gen Virol 2002; 83:2025-2034. [PMID: 12124467 DOI: 10.1099/0022-1317-83-8-2025] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In this report a naturally occurring hypervariable region within the genome of different Cryptophlebia leucotreta granulovirus genotypes is characterized. The region consists of a stretch of direct repeats, short palindromes and an unusual AT-rich region. Although the organization of these repeat sequences is unique to baculoviruses, it has the structural features of a 'non-hr' origin of DNA replication (ori). Restriction analysis and Southern hybridization revealed that this region is expanded during virus replication. Sequence comparison of different isolated genotypes indicated that the expansion is caused by concatenation of short repeats within the region or by concatenation of the complete region. These findings indicate that the expansion of non-hr origin-like regions is not restricted to defective-interfering particles, as was found previously for baculoviruses propagated in cell culture. Moreover, it appears that non-hr complexity contributes to the natural heterogeneity and genetic plasticity of baculovirus genomes. Also, circumstantial evidence is discussed that hr oris might have developed from internal rearrangement and multiplication of a non-hr ori during baculovirus evolution.
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Affiliation(s)
- Johannes A Jehle
- State Education and Research Center for Agriculture, Viticulture and Horticulture (SLFA), Section Biotechnological Crop Protection, Breitenweg 71, 67435 Neustadt an der Weinstraße, Germany1
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203
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Lung O, Westenberg M, Vlak JM, Zuidema D, Blissard GW. Pseudotyping Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV): F proteins from group II NPVs are functionally analogous to AcMNPV GP64. J Virol 2002; 76:5729-36. [PMID: 11992001 PMCID: PMC137061 DOI: 10.1128/jvi.76.11.5729-5736.2002] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
GP64, the major envelope glycoprotein of budded virions of the baculovirus Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV), is involved in viral attachment, mediates membrane fusion during virus entry, and is required for efficient virion budding. Thus, GP64 is essential for viral propagation in cell culture and in animals. Recent genome sequences from a number of baculoviruses show that only a subset of closely related baculoviruses have gp64 genes, while other baculoviruses have a recently discovered unrelated envelope protein named F. F proteins from Lymantria dispar MNPV (LdMNPV) and Spodoptera exigua MNPV (SeMNPV) mediate membrane fusion and are therefore thought to serve roles similar to that of GP64. To determine whether F proteins are functionally analogous to GP64 proteins, we deleted the gp64 gene from an AcMNPV bacmid and inserted F protein genes from three different baculoviruses. In addition, we also inserted envelope protein genes from vesicular stomatitis virus (VSV) and Thogoto virus. Transfection of the gp64-null bacmid DNA into Sf9 cells does not generate infectious particles, but this defect was rescued by introducing either the F protein gene from LdMNPV or SeMNPV or the G protein gene from VSV. These results demonstrate that baculovirus F proteins are functionally analogous to GP64. Because baculovirus F proteins appear to be more widespread within the family and are much more divergent than GP64 proteins, gp64 may represent the acquisition of an envelope protein gene by an ancestral baculovirus. The AcMNPV pseudotyping system provides an efficient and powerful method for examining the functions and compatibilities of analogous or orthologous viral envelope proteins, and it could have important biotechnological applications.
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Affiliation(s)
- Oliver Lung
- Boyce Thompson Institute, Cornell University, Ithaca, New York 14853, USA
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204
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Pearson MN, Rohrmann GF. Transfer, incorporation, and substitution of envelope fusion proteins among members of the Baculoviridae, Orthomyxoviridae, and Metaviridae (insect retrovirus) families. J Virol 2002; 76:5301-4. [PMID: 11991958 PMCID: PMC137044 DOI: 10.1128/jvi.76.11.5301-5304.2002] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- Margot N Pearson
- Department of Microbiology, Oregon State University, Corvallis, Oregon 97331-3804, USA
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205
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Iwanaga M, Kurihara M, Kobayashi M, Kang W. Characterization of Bombyx mori nucleopolyhedrovirus orf68 gene that encodes a novel structural protein of budded virus. Virology 2002; 297:39-47. [PMID: 12083834 DOI: 10.1006/viro.2002.1443] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
All lepidopteran baculovirus genomes sequenced to date encode a homolog of the Bombyx mori nucleopolyhedrovirus (BmNPV) orf68 gene, suggesting that it performs an important role in the virus life cycle. In this article we describe the characterization of BmNPV orf68 gene. Northern and Western analyses demonstrated that orf68 gene was expressed as a late gene and encoded a structural protein of budded virus (BV). Immunohistochemical analysis by confocal microscopy showed that ORF68 protein was localized mainly in the nucleus of infected cells. To examine the function of orf68 gene, we constructed orf68 deletion mutant (BmD68) and characterized it in BmN cells and larvae of B. mori. BV production was delayed in BmD68-infected cells. The larval bioassays also demonstrated that deletion of orf68 did not reduce the infectivity, but mutant virus took 70 h longer to kill the host than wild-type BmNPV. In addition, dot-blot analysis showed viral DNA accumulated more slowly in mutant infected cells. Further examination suggested that BmD68 was less efficient in entry and budding from cells, although it seemed to possess normal attachment ability. These results suggest that ORF68 is a BV-associated protein involved in secondary infection from cell-to-cell.
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Affiliation(s)
- Masashi Iwanaga
- Laboratory of Molecular Entomology and Baculovirology, RIKEN, 2-1, Hirosawa, Wako-shi, 351-0198, Japan
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206
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Hyink O, Dellow RA, Olsen MJ, Caradoc-Davies KMB, Drake K, Herniou EA, Cory JS, O'Reilly DR, Ward VK. Whole genome analysis of the Epiphyas postvittana nucleopolyhedrovirus. J Gen Virol 2002; 83:957-971. [PMID: 11907346 DOI: 10.1099/0022-1317-83-4-957] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The nucleotide sequence of the Epiphyas postvittana nucleopolyhedrovirus (EppoMNPV) genome has been determined and analysed. The circular dsDNA genome contains 118584 bp, making it the smallest group I NPV sequenced to date. The genome has a G+C content of 40.7% and encodes 136 predicted open reading frames (ORFs), five homologous repeat regions and one unique repeat region. Of the genome, 92.9% encodes predicted ORFs and 2.2% is in repeat regions; the remaining 4.9% of the genome comprises nonrepeat intergenic regions. EppoMNPV encodes homologues of 126 Orgyia pseudotsugata MNPV (OpMNPV) ORFs and 120 Autographa californica MNPV ORFs, with average identities of 64.7 and 53.5%, respectively. Between the four sequenced group I NPVs, 117 ORFs are conserved, whereas 86 ORFs are conserved between all fully sequenced NPVs. A total of 62 ORFs is present in all baculoviruses sequenced to date, with EppoMNPV lacking a homologue of the superoxide dismutase (sod) gene, which has been found in all other fully sequenced baculoviruses. Whole genome phylogenetic analyses of the ten fully sequenced baculoviruses using the sequences of the 62 shared genes, gene content and gene order data sets confirmed that EppoMNPV clusters tightly with OpMNPV in the group I NPVs. The main variation between EppoMNPV and OpMNPV occurs where extra clusters of genes are present in OpMNPV, with sod occurring in one such cluster. EppoMNPV encodes one truncated baculovirus repeated ORF (bro) gene. The only repeated ORFs are the four iap genes. Eight, randomly distributed, unique ORFs were identified on EppoMNPV, none of which show any significant homology to genes in GenBank.
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Affiliation(s)
- Otto Hyink
- Department of Microbiology, Otago School of Medical Sciences, University of Otago, PO Box 56, Dunedin, New Zealand1
| | - Ross A Dellow
- Department of Microbiology, Otago School of Medical Sciences, University of Otago, PO Box 56, Dunedin, New Zealand1
| | - Michael J Olsen
- Department of Microbiology, Otago School of Medical Sciences, University of Otago, PO Box 56, Dunedin, New Zealand1
| | - Katherine M B Caradoc-Davies
- Department of Microbiology, Otago School of Medical Sciences, University of Otago, PO Box 56, Dunedin, New Zealand1
| | - Kylie Drake
- Department of Microbiology, Otago School of Medical Sciences, University of Otago, PO Box 56, Dunedin, New Zealand1
| | - Elisabeth A Herniou
- Ecology and Biocontrol Group, Centre for Ecology and Hydrology, Mansfield Road, Oxford OX1 3SR, UK3
- Department of Biological Sciences, Imperial College of Science, Technology and Medicine, London SW7 2AZ, UK2
| | - Jennifer S Cory
- Ecology and Biocontrol Group, Centre for Ecology and Hydrology, Mansfield Road, Oxford OX1 3SR, UK3
| | - David R O'Reilly
- Department of Biological Sciences, Imperial College of Science, Technology and Medicine, London SW7 2AZ, UK2
| | - Vernon K Ward
- Department of Microbiology, Otago School of Medical Sciences, University of Otago, PO Box 56, Dunedin, New Zealand1
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207
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Manzán MA, Lozano ME, Sciocco-Cap A, Ghiringhelli PD, Romanowski V. Identification and characterization of the ecdysteroid UDP-glycosyltransferase gene of Epinotia aporema granulovirus. Virus Genes 2002; 24:119-30. [PMID: 12018702 DOI: 10.1023/a:1014564331383] [Citation(s) in RCA: 8] [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 ecdysteroid UDP-glycosyltransferase (egt) gene of Epinotia aporema granulovirus (EpapGV) was cloned sequenced and its biological activity was assessed. It encodes a protein of 446 amino acids. Direct evidence that the cloned gene encodes an active EGT protein was obtained by transient expression assays in insect cells. The upstream untranslated region of the egt gene exhibits several consensus early promoter elements. Accordingly, the gene is expressed early upon infection of Epinotia aporema larvae and the EGT activity remains high until later times post infection. Sequence analyses indicate the presence of clusters of amino acid residues conserved among all the baculoviral EGTs, although their relation with proper protein folding, ligand binding and catalytic activity remain to be assessed. Phylogenetic trees consistently cluster the granulovirus EGTs separating them clearly from the nucleopolyhedroviruses.
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Affiliation(s)
- María Alejandra Manzán
- Instituto de Bioquímica y Biología Molecular, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Argentina
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208
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Chen X, Zhang WJ, Wong J, Chun G, Lu A, McCutchen BF, Presnail JK, Herrmann R, Dolan M, Tingey S, Hu ZH, Vlak JM. Comparative analysis of the complete genome sequences of Helicoverpa zea and Helicoverpa armigera single-nucleocapsid nucleopolyhedroviruses. J Gen Virol 2002; 83:673-684. [PMID: 11842262 DOI: 10.1099/0022-1317-83-3-673] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The complete nucleotide sequence of Helicoverpa zea single-nucleocapsid nucleopolyhedrovirus (HzSNPV) has been determined (130869 bp) and compared to the nucleotide sequence of Helicoverpa armigera (Ha) SNPV. These two genomes are very similar in their nucleotide (97% identity) and amino acid (99% identity) sequences. The coding regions are much more conserved than the non-coding regions. In HzSNPV/HaSNPV, the 63 open reading frames (ORFs) present in all baculoviruses sequenced so far are much more conserved than other ORFs. HzSNPV has four additional small ORFs compared with HaSNPV, one of these (Hz42) being in a correct transcriptional context. The major differences between HzSNPV and HaSNPV are found in the sequence and organization of the homologous regions (hrs) and the baculovirus repeat ORFs (bro genes). The sequence identity between the HzSNPV and HaSNPV hrs ranges from 90% (hr1) to almost 100% (hr5) and the hrs differ in the presence/absence of one or more type A and/or B repeats. The three HzSNPV bro genes differ significantly from those in HaSNPV and may have been acquired independently in the ancestral past. The sequence data suggest strongly that HzSNPV and HaSNPV are variants of the same virus species, a conclusion that is supported by the physical and biological data.
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Affiliation(s)
- Xinwen Chen
- Joint Lab of Invertebrate Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, People's Republic of China2
- Laboratory of Virology, Wageningen University, Binnenhaven 11, 6709 PD Wageningen, The Netherlands1
| | - W-J Zhang
- Dupont Agricultural Products, Stine-Haskell Research Center, E.I. du Pont de Nemours and Co., PO Box 30, Newark, DE 19714-0030, USA3
| | - J Wong
- Dupont Agricultural Products, Stine-Haskell Research Center, E.I. du Pont de Nemours and Co., PO Box 30, Newark, DE 19714-0030, USA3
| | - G Chun
- Dupont Agricultural Products, Stine-Haskell Research Center, E.I. du Pont de Nemours and Co., PO Box 30, Newark, DE 19714-0030, USA3
| | - A Lu
- Dupont Agricultural Products, Stine-Haskell Research Center, E.I. du Pont de Nemours and Co., PO Box 30, Newark, DE 19714-0030, USA3
| | - B F McCutchen
- Dupont Agricultural Products, Stine-Haskell Research Center, E.I. du Pont de Nemours and Co., PO Box 30, Newark, DE 19714-0030, USA3
| | - J K Presnail
- Dupont Agricultural Products, Stine-Haskell Research Center, E.I. du Pont de Nemours and Co., PO Box 30, Newark, DE 19714-0030, USA3
| | - R Herrmann
- Dupont Agricultural Products, Stine-Haskell Research Center, E.I. du Pont de Nemours and Co., PO Box 30, Newark, DE 19714-0030, USA3
| | - M Dolan
- Dupont Agricultural Products, Stine-Haskell Research Center, E.I. du Pont de Nemours and Co., PO Box 30, Newark, DE 19714-0030, USA3
| | - S Tingey
- Dupont Agricultural Products, Stine-Haskell Research Center, E.I. du Pont de Nemours and Co., PO Box 30, Newark, DE 19714-0030, USA3
| | - Z H Hu
- Joint Lab of Invertebrate Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, People's Republic of China2
| | - Just M Vlak
- Laboratory of Virology, Wageningen University, Binnenhaven 11, 6709 PD Wageningen, The Netherlands1
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209
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Li Q, Donly C, Li L, Willis LG, Theilmann DA, Erlandson M. Sequence and organization of the Mamestra configurata nucleopolyhedrovirus genome. Virology 2002; 294:106-21. [PMID: 11886270 DOI: 10.1006/viro.2001.1313] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The nucleotide sequence of the genome of the nucleopolyhedrovirus (NPV) from Mamestra configurata (MacoNPV, isolate 90/2), a group II NPV, was determined and analyzed. The MacoNPV DNA genome consists of 155,060 bp and has an overall G+C content of 41.7%. Computer-assisted analysis predicted 169 open reading frames (ORFs) of 150 nucleotides or greater that showed minimal overlap. BLAST searches and comparisons with completely sequenced baculoviruses indicated that there were 66 ORFs conserved among the nine baculoviruses compared and an additional 17 ORFs were conserved among the NPVs. The gene content and gene arrangement in MacoNPV were most similar to those of SeMNPV, including two putative odv-e66 and p26 gene homologues. However, in contrast to SeMNPV, 8 ORFs with homology to baculovirus repeat ORFs (bro) and single copies of enhancin and conotoxin-like protein ORFs were found in MacoNPV. The MacoNPV genome contained four homologous regions, each with 10 to 17 repeated sequences. Each repeat was 60 to 86 nucleotides in length and contained an approximately 43-bp-long imperfect palindrome. There were 13 ORFs unique to MacoNPV, ranging from a small ORF of 196 bp to larger ORFs of up to 1047 bp, and many of these contained typical early and late baculovirus consensus promoters.
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Affiliation(s)
- Qianjun Li
- Saskatoon Research Centre, Agriculture and Agri-Food Canada, Saskatoon, Saskatchewan, S7N 0X2 Canada
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210
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Wolff JLC, Moraes RHP, Kitajima E, de Souza Leal E, de A Zanotto PM. Identification and characterization of a baculovirus from Lonomia obliqua (Lepidoptera: Saturniidae). J Invertebr Pathol 2002; 79:137-45. [PMID: 12133702 DOI: 10.1016/s0022-2011(02)00030-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A baculovirus has been isolated from larvae of Lonomia obliqua, a Saturniidae of medical importance due to a potent toxin found in their spines. Electron Microscopy analysis of the occlusion body obtained from diseased larvae showed polyhedra of approximately 1 microm in diameter containing multiple nucleocapsids per envelope. This baculovirus was thus named Lonomia obliqua multicapsid nucleopolyhedrovirus (LoobMNPV). Restriction endonuclease profiles of viral DNA digested with three restriction enzymes were obtained and the genome size was estimated to be 95.52 +/- 2.3 kbp. The polyhedrin gene of LoobMNPV was identified and its DNA sequence was determined. Phylogenetic analysis of the polyhedrin gene showed that the LoobMNPV polyhedrin belongs to group I NPV and that it is closely related to the polyhedrin of the NPV of Amsacta albistriga.
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Affiliation(s)
- José Luiz C Wolff
- Laboratório de Virologia Molecular, Núcleo Integrado de Biotecnologia, Universidade de Mogi das Cruzes, Av. Dr. Cândido, Xavier de Almeida, Souza, 200, 08780-911, Mogi das Cruzes, SP, Brazil.
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211
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Huang YJ, Kobayashi J, Yoshimura T. Genome mapping and gene analysis of Antheraea pernyi nucleopolyhedrovirus for improvement of baculovirus expression vector system. J Biosci Bioeng 2002. [DOI: 10.1016/s1389-1723(02)80012-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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212
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Current Awareness on Comparative and Functional Genomics. Comp Funct Genomics 2002. [PMCID: PMC2447231 DOI: 10.1002/cfg.116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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213
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Herniou EA, Olszewski JA, Cory JS, O'Reilly DR. The genome sequence and evolution of baculoviruses. ANNUAL REVIEW OF ENTOMOLOGY 2001; 48:211-234. [PMID: 12414741 DOI: 10.1146/annurev.ento.48.091801.112756] [Citation(s) in RCA: 326] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Comparative analysis of the complete genome sequences of 13 baculoviruses revealed a core set of 30 genes, 20 of which have known functions. Phylogenetic analyses of these 30 genes yielded a tree with 4 major groups: the genus Granulovirus (GVs), the group I and II lepidopteran nucleopolyhedroviruses (NPVs), and the dipteran NPV, CuniNPV. These major divisions within the family Baculoviridae were also supported by phylogenies based on gene content and gene order. Gene content mapping has revealed the patterns of gene acquisitions and losses that have taken place during baculovirus evolution, and it has highlighted the fluid nature of baculovirus genomes. The identification of shared protein phylogenetic profiles provided evidence for two putative DNA repair systems and for viral proteins specific for infection of lymantrid hosts. Examination of gene order conservation revealed a core gene cluster of four genes, helicase, lef-5, ac96, and 38K(ac98), whose relative positions are conserved in all baculovirus genomes.
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Affiliation(s)
- Elisabeth A Herniou
- Department of Biological Sciences, Imperial College of Science, Technology and Medicine, London SW7 2AZ, United Kingdom.
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