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Bruder MR, Aucoin MG. Utility of Alternative Promoters for Foreign Gene Expression Using the Baculovirus Expression Vector System. Viruses 2022; 14:v14122670. [PMID: 36560674 PMCID: PMC9786725 DOI: 10.3390/v14122670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 10/27/2022] [Accepted: 10/31/2022] [Indexed: 12/03/2022] Open
Abstract
The baculovirus expression vector system (BEVS) is a widely used platform for recombinant protein production for use in a wide variety of applications. Of particular interest is production of virus-like particles (VLPs), which consist of multiple viral proteins that self-assemble in strict stoichiometric ratios to mimic the structure of a virus but lacks its genetic material, while a significant amount of effort has been spent on optimizing expression ratios by co-infecting cells with multiple recombinant BEVs and modulating different process parameters, co-expressing multiple foreign genes from a single rBEV may offer more promise. However, there is currently a lack of promoters available with which to optimize co-expression of each foreign gene. To address this, previously published transcriptome data was used to identify promoters that have incrementally lower expression profiles and compared by expressing model cytoplasmic and secreted proteins. Bioinformatics was also used to identify sequence determinants that may be important for late gene transcription regulation, and translation initiation. The identified promoters and bioinformatics analyses may be useful for optimizing expression of foreign genes in the BEVS.
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Korn J, Schäckermann D, Kirmann T, Bertoglio F, Steinke S, Heisig J, Ruschig M, Rojas G, Langreder N, Wenzel EV, Roth KDR, Becker M, Meier D, van den Heuvel J, Hust M, Dübel S, Schubert M. Baculovirus-free insect cell expression system for high yield antibody and antigen production. Sci Rep 2020; 10:21393. [PMID: 33288836 PMCID: PMC7721901 DOI: 10.1038/s41598-020-78425-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 11/20/2020] [Indexed: 11/09/2022] Open
Abstract
Antibodies are essential tools for therapy and diagnostics. Yet, production remains expensive as it is mostly done in mammalian expression systems. As most therapeutic IgG require mammalian glycosylation to interact with the human immune system, other expression systems are rarely used for production. However, for neutralizing antibodies that are not required to activate the human immune system as well as antibodies used in diagnostics, a cheaper production system would be advantageous. In our study, we show cost-efficient, easy and high yield production of antibodies as well as various secreted antigens including Interleukins and SARS-CoV-2 related proteins in a baculovirus-free insect cell expression system. To improve yields, we optimized the expression vector, media and feeding strategies. In addition, we showed the feasibility of lyophilization of the insect cell produced antibodies. Furthermore, stability and activity of the antibodies was compared to antibodies produced by Expi293F cells revealing a lower aggregation of antibodies originating from High Five cell production. Finally, the newly established High Five expression system was compared to the Expi293F mammalian expression system in regard of yield and costs. Most interestingly, all tested proteins were producible in our High Five cell expression system what was not the case in the Expi293F system, hinting that the High Five cell system is especially suited to produce difficult-to-express target proteins.
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Affiliation(s)
- Janin Korn
- Department of Biotechnology, Technische Universität Braunschweig, Spielmannstraße 7, 38106, Braunschweig, Germany
| | - Dorina Schäckermann
- Department of Biotechnology, Technische Universität Braunschweig, Spielmannstraße 7, 38106, Braunschweig, Germany
| | - Toni Kirmann
- Department of Biotechnology, Technische Universität Braunschweig, Spielmannstraße 7, 38106, Braunschweig, Germany
- Medical Faculty, Carl Ludwig Institute for Physiology, Universität Leipzig, Liebigstraße 27, 04103, Leipzig, Germany
| | - Federico Bertoglio
- Department of Biotechnology, Technische Universität Braunschweig, Spielmannstraße 7, 38106, Braunschweig, Germany
| | - Stephan Steinke
- Department of Biotechnology, Technische Universität Braunschweig, Spielmannstraße 7, 38106, Braunschweig, Germany
| | - Janyn Heisig
- Department of Biotechnology, Technische Universität Braunschweig, Spielmannstraße 7, 38106, Braunschweig, Germany
- Department Vaccinology and Applied Microbiology, Helmholtz Centre for Infection Research, Inhoffenstraße 7, 38124, Braunschweig, Germany
| | - Maximilian Ruschig
- Department of Biotechnology, Technische Universität Braunschweig, Spielmannstraße 7, 38106, Braunschweig, Germany
| | - Gertrudis Rojas
- Center of Molecular Immunology, PO Box 16040, 11300, Havana, Cuba
| | - Nora Langreder
- Department of Biotechnology, Technische Universität Braunschweig, Spielmannstraße 7, 38106, Braunschweig, Germany
| | - Esther Veronika Wenzel
- Department of Biotechnology, Technische Universität Braunschweig, Spielmannstraße 7, 38106, Braunschweig, Germany
| | - Kristian Daniel Ralph Roth
- Department of Biotechnology, Technische Universität Braunschweig, Spielmannstraße 7, 38106, Braunschweig, Germany
| | - Marlies Becker
- Department of Biotechnology, Technische Universität Braunschweig, Spielmannstraße 7, 38106, Braunschweig, Germany
| | - Doris Meier
- Department of Biotechnology, Technische Universität Braunschweig, Spielmannstraße 7, 38106, Braunschweig, Germany
| | - Joop van den Heuvel
- Department Structure and Function of Proteins, Helmholtz-Centre for Infection Research, Inhoffenstraße 7, 38124, Braunschweig, Germany
| | - Michael Hust
- Department of Biotechnology, Technische Universität Braunschweig, Spielmannstraße 7, 38106, Braunschweig, Germany
| | - Stefan Dübel
- Department of Biotechnology, Technische Universität Braunschweig, Spielmannstraße 7, 38106, Braunschweig, Germany
| | - Maren Schubert
- Department of Biotechnology, Technische Universität Braunschweig, Spielmannstraße 7, 38106, Braunschweig, Germany.
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de Pinheiro CGM, Pedrosa MDO, Teixeira NC, Ano Bom APD, van Oers MM, Oliveira GGDS. Optimization of canine interleukin-12 production using a baculovirus insect cell expression system. BMC Res Notes 2016; 9:36. [PMID: 26795376 PMCID: PMC4722752 DOI: 10.1186/s13104-016-1843-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Accepted: 01/08/2016] [Indexed: 12/11/2022] Open
Abstract
Background Interleukin-12 is an important cytokine in mediating cellular immune responses. Results Recombinant single-chain canine IL-12 was produced in a baculovirus-insect cell system with the aim of conducting further studies on modulation of immune responses in dogs. To optimize the production of recombinant canine IL-12, a classical baculovirus and a modified vector (chitinase A and v-cathepsin knockout) were used containing a native or an optimized insert of canine IL-12.
The optimized IL-12 construct contained the GP64 signal peptide and was synthesized with optimized codons for expression in Trichoplusia ni cells. Dot-blot and Western blot analysis showed the highest production levels of recombinant IL-12 protein by the use of the modified baculovirus vector containing the optimized insert, at a multiplicity of infection of five and at 48 h after infection. The recombinant cytokine was successfully purified and showed a good degree of purity, integrity, folding, and yield, with very little endotoxin contamination. Recombinant canine IL-12 induced IFN-γ in canine lymphocytes, indicating that it was biologically active. Conclusion Therefore, this study describes an efficient method to produce adequate amounts of biologically active canine IL-12, useful for immunomodulation studies in dogs.
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Affiliation(s)
- Cristiane Garboggini Melo de Pinheiro
- Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Bahia, Brazil. .,Programa Nacional de Pós Doutorado-CAPES/Programa de Pós-graduação em Biotecnologia em Saúde e Medicina Investigativa, Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Bahia, Brazil.
| | | | | | - Ana Paula Dinis Ano Bom
- Laboratório de Macromoléculas, Bio-Manguinhos, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.
| | - Monique M van Oers
- Laboratory of Virology, Wageningen University, Wageningen, The Netherlands.
| | - Geraldo Gileno de Sá Oliveira
- Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Bahia, Brazil. .,Instituto Nacional de Ciência e Tecnologia de Doenças Tropicais (INCT-DT), Salvador, Brazil.
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Tatematsu KI, Uchino K, Sezutsu H, Tamura T. Effect of ATG initiation codon context motifs on the efficiency of translation of mRNA derived from exogenous genes in the transgenic silkworm, Bombyx mori. SPRINGERPLUS 2014; 3:136. [PMID: 25674439 PMCID: PMC4320137 DOI: 10.1186/2193-1801-3-136] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Accepted: 03/03/2014] [Indexed: 01/17/2023]
Abstract
The context sequence motif surrounding the ATG initiation codon influences mRNA translation efficiency and affects protein production; however, the optimal sequence differs among species. To determine the optimal sequence for production of recombinant proteins in a transgenic silkworm, we compared 14-nucleotide context motifs around the ATG (ATG-context) in 50 silkworm genes and found the following consensus: (A/T)AN(A/T)ATCAAAatgN. We were also able to define the least-common motif: CCN(C/G)CGN(C/T/G)(G/C/T)(T/G)atgC, which served as a negative control. To examine the regulatory role of these motifs in protein expression, we constructed reporter plasmids containing different ATG-context motifs together with either the luciferase gene or an enhanced green fluorescent protein (EGFP) gene. These constructs were then used for comparison of luciferase reporter activity and EGFP production in BmN4 cells in vitro as well as in transgenic silkworms in vivo. We detected 10-fold higher luciferase activity in BmN4 cells transfected with the consensus ATG-context motif construct, compared to the negative control plasmid. ELISA measurements of EGFP translation products with the corresponding constructs in BmN4 cells showed consistently similar results. Interestingly, the translation efficiency of the novel consensus ATG-context motif did not show the highest activity in the transgenic silkworms in vivo, except for the fat body. The highest efficiency in the middle and posterior silk glands was produced by the sericin 1 context. Our results show that the ATG-context motifs differ among silkworm tissues. This result is important for the further improvement of the transgenic silkworm system for the production of recombinant proteins.
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Affiliation(s)
- Ken-Ichiro Tatematsu
- Transgenic Silkworm Research Unit, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki 305-8634 Japan
| | - Keiro Uchino
- Transgenic Silkworm Research Unit, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki 305-8634 Japan
| | - Hideki Sezutsu
- Transgenic Silkworm Research Unit, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki 305-8634 Japan
| | - Toshiki Tamura
- Transgenic Silkworm Research Unit, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki 305-8634 Japan
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Shen X, Hacker DL, Baldi L, Wurm FM. Virus-free transient protein production in Sf9 cells. J Biotechnol 2014; 171:61-70. [DOI: 10.1016/j.jbiotec.2013.11.018] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Revised: 11/25/2013] [Accepted: 11/26/2013] [Indexed: 12/31/2022]
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Monitoring of the effects of transfection with baculovirus on Sf9 cell line and expression of human dipeptidyl peptidase IV. Cytotechnology 2013; 66:159-68. [PMID: 23715645 DOI: 10.1007/s10616-013-9549-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2012] [Accepted: 02/18/2013] [Indexed: 10/26/2022] Open
Abstract
Human dipeptidylpeptidase IV (hDPPIV) is an enzyme that is in hydrolase class and has various roles in different parts of human body. Its deficiency may cause some disorders in the gastrointestinal, neurologic, endocrinological and immunological systems of humans. In the present study, hDPPIV enzyme was expressed on Spodoptera frugiperda (Sf9) cell lines as a host cell, and the expression of hDPPIV was obtained by a baculoviral expression system. The enzyme production, optimum multiplicity of infection, optimum transfection time, infected and uninfected cell size and cell behavior during transfection were also determined. For maximum hDPPIV (269 mU mL(-1)) enzyme, optimum multiplicity of infection (MOI) and time were 0.1 and 72 h, respectively. The size of infected cells increased significantly (P < 0.001) after 24 h post infection. The results indicated that Sf9 cell line was applicable to the large scale for hDPPIV expression by using optimized parameters (infection time and MOI) because of its high productivity (4.03 mU m L(-1) h(-1)).
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Opportunities and challenges for the baculovirus expression system. J Invertebr Pathol 2011; 107 Suppl:S3-15. [PMID: 21784228 DOI: 10.1016/j.jip.2011.05.001] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Revised: 01/28/2011] [Accepted: 01/28/2011] [Indexed: 11/23/2022]
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Ogay ID, Lihoradova OA, Azimova SS, Abdukarimov AA, Slack JM, Lynn DE. Transfection of insect cell lines using polyethylenimine. Cytotechnology 2006; 51:89-98. [PMID: 19002899 PMCID: PMC3449679 DOI: 10.1007/s10616-006-9022-7] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2006] [Accepted: 08/28/2006] [Indexed: 11/24/2022] Open
Abstract
Insect cell lines have been widely used in recombinant baculovirus expression systems and transient gene expression studies. Critical to these applications have been the transfection of foreign DNA. This has been frequently done using labor intensive and cytotoxic liposome-based transfection reagents. In the current study we have optimized a new kind of polyethylenimine-based DNA transfection reagent on the Spodoptera frugiperda Sf9 insect cell line. A plasmid vector that transiently expresses green fluorescent protein (GFP) was effectively delivered into Sf9 cells. A transfection efficiency of 54% and cell viability of 85-90% were obtained for Sf9 cells. The developed transfection protocol has now been successfully used to transfect eight insect cell lines derived from Bombyx mori, Trichoplusia ni, Helicoverpa zea, Heliothis virescens and S. frugiperda with GFP and GUS with transfection efficiencies of at least 45%. This method provides high heterologous protein expression levels, transfection efficacy and cell viability, and could be used for transient gene expression in other lepidopteran cell lines.
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Affiliation(s)
- I. D. Ogay
- Institute of Genetics and Plant Experimental Biology, Uzbek Academy of Science Tashkent region, Qibray district, Yuqori-Yuz 702151 Uzbekistan
- Institute of the Chemistry of Plant Substances, Uzbek Academy of Science, Tashkent, 700170 Uzbekistan
| | - O. A. Lihoradova
- Institute of Genetics and Plant Experimental Biology, Uzbek Academy of Science Tashkent region, Qibray district, Yuqori-Yuz 702151 Uzbekistan
- Institute of the Chemistry of Plant Substances, Uzbek Academy of Science, Tashkent, 700170 Uzbekistan
| | - Sh. S. Azimova
- Institute of the Chemistry of Plant Substances, Uzbek Academy of Science, Tashkent, 700170 Uzbekistan
| | - A. A. Abdukarimov
- Institute of Genetics and Plant Experimental Biology, Uzbek Academy of Science Tashkent region, Qibray district, Yuqori-Yuz 702151 Uzbekistan
| | - J. M. Slack
- Insect Biocontrol Laboratory, USDA/ARS, BARC-West, Bldg 011A, Rm 214, Beltsville, MD 20852-2350 USA
- Great Lakes Forestry Centre, Canadian Forestry Service, Natural Resources Canada, 1219 Queen St, P6A 2E5 Sault Ste Marie, ON Canada
| | - D. E. Lynn
- Insect Biocontrol Laboratory, USDA/ARS, BARC-West, Bldg 011A, Rm 214, Beltsville, MD 20852-2350 USA
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Abstract
The baculovirus-insect cell expression system is an approved system for the production of viral antigens with vaccine potential for humans and animals and has been used for production of subunit vaccines against parasitic diseases as well. Many candidate subunit vaccines have been expressed in this system and immunization commonly led to protective immunity against pathogen challenge. The first vaccines produced in insect cells for animal use are now on the market. This chapter deals with the tailoring of the baculovirus-insect cell expression system for vaccine production in terms of expression levels, integrity and immunogenicity of recombinant proteins, and baculovirus genome stability. Various expression strategies are discussed including chimeric, virus-like particles, baculovirus display of foreign antigens on budded virions or in occlusion bodies, and specialized baculovirus vectors with mammalian promoters that express the antigen in the immunized individual. A historical overview shows the wide variety of viral (glyco)proteins that have successfully been expressed in this system for vaccine purposes. The potential of this expression system for antiparasite vaccines is illustrated. The combination of subunit vaccines and marker tests, both based on antigens expressed in insect cells, provides a powerful tool to combat disease and to monitor infectious agents.
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Affiliation(s)
- Monique M van Oers
- Laboratory of Virology, Wageningen University, Binnenhaven 11 6709 PD, Wageningen, The Netherlands
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10
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Giannopoulos PN, Nassoury N, Lamontagne L, Guertin C, Rashidan KK. Choristoneura fumiferana Granulovirus pk-1: a baculoviral protein kinase. JOURNAL OF BIOCHEMISTRY AND MOLECULAR BIOLOGY 2005; 38:457-67. [PMID: 16053713 DOI: 10.5483/bmbrep.2005.38.4.457] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Open reading frame (ORF) 3 on the Choristoneura fumiferana granulovirus (ChfuGV), located in the 11 kb fragment of the BamHI genomic bank encodes a predicted 32-kDa putative kinase protein. Bioinformatics analysis on the predicted amino acid sequence of ChfuGV PK-1 revealed the existence of 11 catalytic subdomains. Sequence analysis within the 5'-untranslated region (5'-UTR) of ChfuGV pk- 1 indicates the presence of both putative early and late promoter motifs, indicating that pk-1 may be expressed throughout the infection cycle. Promoter sequence analysis reveals that pk-1 is deprived of a TATA box and appears instead to be regulated by other cis-acting transcriptional regulatory elements. Temporal transcription analysis by RT-PCR confirms the appearance of transcripts detected from 2 h p.i. until 72 h p.i. Northern blot hybridization characterizes pk-1 transcription as a 1.2 kb transcript. Homology comparisons reveal that ChfuGV PK-1 protein is most closely related to Phthorimaea operculalla granulovirus (PoGV) with 80 % amino acid identity.
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Affiliation(s)
- Paresa N Giannopoulos
- Institut national de la recherche scientifique-Institut Armand-Frappier, Laval, Canada
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11
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Johnson KN, Tang L, Johnson JE, Ball LA. Heterologous RNA encapsidated in Pariacoto virus-like particles forms a dodecahedral cage similar to genomic RNA in wild-type virions. J Virol 2004; 78:11371-8. [PMID: 15452258 PMCID: PMC521806 DOI: 10.1128/jvi.78.20.11371-11378.2004] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The genome of some icosahedral RNA viruses plays an essential role in capsid assembly and structure. In T=3 particles of the nodavirus Pariacoto virus (PaV), a remarkable 35% of the single-stranded RNA genome is icosahedrally ordered. This ordered RNA can be visualized at high resolution by X-ray crystallography as a dodecahedral cage consisting of 30 24-nucleotide A-form RNA duplex segments that each underlie a twofold icosahedral axis of the virus particle and interact extensively with the basic N-terminal region of 60 subunits of the capsid protein. To examine whether the PaV genome is a specific determinant of the RNA structure, we produced virus-like particles (VLPs) by expressing the wild-type capsid protein open reading frame from a recombinant baculovirus. VLPs produced by this system encapsidated similar total amounts of RNA as authentic virus particles, but only about 6% of this RNA was PaV specific, the rest being of cellular or baculovirus origin. Examination of the VLPs by electron cryomicroscopy and image reconstruction at 15.4-A resolution showed that the encapsidated RNA formed a dodecahedral cage similar to that of wild-type particles. These results demonstrate that the specific nucleotide sequence of the PaV genome is not required to form the dodecahedral cage of ordered RNA.
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Affiliation(s)
- Karyn N Johnson
- Department of Microbiology, University of Alabama at Birmingham, BBRB 373/17, 845 19th St. South, Birmingham, AL 35294-2170, USA
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Zhao KN, Tomlinson L, Liu WJ, Gu W, Frazer IH. Effects of additional sequences directly downstream from the AUG on the expression of GFP gene. ACTA ACUST UNITED AC 2004; 1630:84-95. [PMID: 14654238 DOI: 10.1016/j.bbaexp.2003.09.010] [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] [Indexed: 10/26/2022]
Abstract
We have studied the expression of the green fluorescent protein (GFP) gene to gain more understanding of the effects of additional nucleotide triplets (codons) downstream from the initiation codon on the translation of the GFP mRNA in CHO and Cos1 cells. A leader sequence of six consecutive identical codons (GUG, CUC, AGU or UCA) was introduced into a humanized GFP (hm gfp) gene downstream from the AUG to produce four GFP gene variants. Northern blot and RT-PCR analysis indicated that mRNA transcription from the GFP gene was not significantly affected by any of the additional sequences. However, immunoblotting and FACS analysis revealed that AGU and UCA GFP variants produced GFP at a mean level per cell 3.5-fold higher than the other two GFP variants and the hm gfp gene. [35S]-Methionine labeling and immunoprecipitation demonstrate that GFP synthesis was very active in UCA variant transfected-cells, but not in GUG variant and hm gfp transfected-cells. Moreover, proteasome inhibitor MG-132 treatment indicated that the GFPs encoded by each of the GFP variants and the hm gfp were equally stable, and this together with the comparable mRNA levels observed for each construct suggested that the different steady-state GFP concentrations observed reflected different translation efficiencies of the various GFP genes. In addition, the CUC GFP variant, when transiently transfected into CHO or COS-1 cells, did not produce any GFP expressing cells (fully green cells), and the GUG variant produced GFP expressing cells less than 10%, while AGU and UCA GFP variants up to 30-35% in a time course study from 8 to 36 h posttransfection. Analysis of the potential secondary structure of the GFP variant mRNAs especially in the translation initiation region suggested that the secondary structure of the GFP mRNAs was unlikely to explain the different translation efficiencies of the GFP variants. The present findings indicate that a change of the initiation context of the GFP gene by addition of extra coding sequence can alter the translation efficiency of GFP mRNA, providing a means of more efficient expression of GFP in eukaryotic cells.
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Affiliation(s)
- Kong-Nan Zhao
- Centre for Immunology and Cancer Research, University of Queensland, Princess Alexandra Hospital, Woolloongabba, Queensland, 4102, Australia.
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van Oers MM, Doitsidou M, Thomas AAM, de Maagd RA, Vlak JM. Translation of both 5'TOP and non-TOP host mRNAs continues into the late phase of Baculovirus infection. INSECT MOLECULAR BIOLOGY 2003; 12:75-84. [PMID: 12542638 DOI: 10.1046/j.1365-2583.2003.00389.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Complete cDNA sequences were obtained for ribosomal protein (rp) L15 and eukaryotic initiation factor eIF2alpha from the lepidopteran insect Spodoptera frugiperda, and for elongation factor eEF2 from S. exigua. The presence of a 5' terminal oligopyrimidine (TOP) tract classified the lepidopteran rpL15 transcript as a TOP mRNA. For eEF2, two types of transcripts were observed, one of which had a 5'TOP tract. The transcript levels for rpL15, eEF2 and eIF2alpha decreased following baculovirus infection. Polysome analysis showed that the corresponding mRNAs remained to be translated until at least 16 h post-infection for both TOP and non-TOP mRNAs. Baculovirus-induced host shut-off therefore appears to be regulated at the level of RNA abundance rather than at the translational level.
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Affiliation(s)
- M M van Oers
- Laboratory of Virology, Wageningen University, Binnenhaven 11, 6709 PD Wageningen, The Netherlands.
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Lin G, Blissard GW. Analysis of an Autographa californica nucleopolyhedrovirus lef-11 knockout: LEF-11 is essential for viral DNA replication. J Virol 2002; 76:2770-9. [PMID: 11861844 PMCID: PMC135986 DOI: 10.1128/jvi.76.6.2770-2779.2002] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The Autographa californica nucleopolyhedrovirus (AcMNPV) lef-11 gene was previously identified by transient late expression assays as a gene important for viral late gene expression. The lef-11 gene was not previously identified as necessary for DNA replication in transient origin-dependent plasmid DNA replication assays. To examine the role of lef-11 in the context of the infection cycle, we generated a deletion of the lef-11 gene by recombination in an AcMNPV genome propagated as a BACmid in Escherichia coli. The resulting AcMNPV lef-11-null BACmid (vAc(lef11KO)) was unable to propagate in cell culture, although a "repair" AcMNPV BACmid (vAc(lef11KO-REP)), which was generated by transposition of the lef-11 gene into the polyhedrin locus of the vAc(lef11KO) BACmid, was able to replicate in a manner similar to wild-type or control AcMNPV viruses. Thus, the lef-11 gene is essential for viral replication in Sf9 cells. The vAc(lef11KO) BACmid was examined to determine if the defect in viral replication resulted from a defect in DNA replication or from a defect in late transcription. The lef-11-null BACmid and control BACmids were transfected into Sf9 cells, and viral DNA replication was monitored. The viral DNA genome of the lef-11-null BACmid (vAc(lef11KO)) was not amplified, whereas replication and amplification of the genomes of the repair BACmid (vAc(lef11KO-REP)), wild-type AcMNPV, and a nonpropagating gp64-null control BACmid (vAc(GUSgp64KO)) were readily detected. Northern blot analysis of transcripts from selected early, late, and very late genes showed that late and very late transcription was absent in cells transfected with the lef-11-null BACmid. Thus, in contrast to prior studies using transient replication and late expression assays, studies of a lef-11-null BACmid indicate that LEF-11 is required for viral DNA replication during the infection cycle.
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Affiliation(s)
- Guangyun Lin
- Boyce Thompson Institute, Cornell University, Ithaca, New York 14853-1801, USA
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Hartley JL. Use of the Gateway System for Protein Expression in Multiple Hosts. ACTA ACUST UNITED AC 2002; Chapter 5:5.17.1-5.17.10. [DOI: 10.1002/0471140864.ps0517s30] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- James L. Hartley
- Science Applications International Corporation (SAIC)/National Cancer Institute Frederick Maryland
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Theilmann DA, Willis LG, Bosch BJ, Forsythe IJ, Li Q. The baculovirus transcriptional transactivator ie0 produces multiple products by internal initiation of translation. Virology 2001; 290:211-23. [PMID: 11883186 DOI: 10.1006/viro.2001.1165] [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
Ie0 is the only gene of the baculovirus Orgyia pseudotsugata multiple nucleopolyhedrovirus (OpMNPV) that is known to be spliced. In this study, cDNAs of ie0 were isolated, cloned, and sequenced. It was observed that IE0 contains 35 amino acids (aa) added to the N-terminus of IE1. In addition, it was found that the leader sequence of ie0 contains a 4-aa minicistron. To functionally characterize IE0, ie0 cDNAs were expressed under control of either the ie1 or the ie0 promoter. Unexpectedly, examination of ie0 translation products revealed that the predominant product from ie0 mRNAs was not IE0, but IE1. Mutation analysis showed that IE1 translation was preferentially initiated from either of two AUGs found in the first 15 nucleotides (nt) of the ie1 ORF that are internal to the ie0 ORF. It is unknown whether the internal translation initiation occurs via a leaky scanning mechanism or by an internal ribosomal entry site. Transactivation analysis with constructs that had point mutations in the ie1 AUGs and were translated only as IE0 revealed that OpMNPV IE0 is a 14- to 15-fold stronger transactivator than IE1. IE0 was also shown to be autoregulatory and to transactivate early genes in an enhancer-independent or -dependent manner. These results suggest that differential expression of baculovirus early genes can be obtained by coexpression of IE0 and IE1 in infected cells, which may permit subtle regulation of specific sets of viral genes.
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Affiliation(s)
- D A Theilmann
- Pacific Agri-Food Research Centre, Agriculture and Agri-Food Canada, 4200 Highway 97, Summerland, British Columbia V0H 1Z0, Canada
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Slack JM, Dougherty EM, Lawrence SD. A study of the Autographa californica multiple nucleopolyhedrovirus ODV envelope protein p74 using a GFP tag. J Gen Virol 2001; 82:2279-2287. [PMID: 11514740 DOI: 10.1099/0022-1317-82-9-2279] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The Autographa californica multiple nucleopolyhedrovirus (AcMNPV) protein p74 is associated with the occlusion-derived virus (ODV) envelope. p74 is essential for oral infectivity of ODV and has been proposed to play a role in midgut attachment and/or fusion. In this study, p74 protein was expressed in-frame with green fluorescent protein (GFP) to create a p74-GFP chimera. The C-terminal GFP portion of the chimera facilitated visualization of the trafficking of p74 in baculovirus-infected Spodoptera frugiperda (Sf-9) cells. p74-GFP chimeric proteins localized in the intranuclear ring zone of the nucleus and were found to co-precipitate with the microvesicle fraction of cell lysates. A series of truncations of p74 was expressed as p74-GFP chimeras in recombinant baculoviruses. When C-terminal region S580-F645 was deleted from p74, p74-GFP chimera localization became non-specific and chimeras became soluble. p74 region S580-F645 directed GFP to the intranuclear ring zone in a similar pattern to full-length p74. The hydrophobic C terminus of p74 plays a role in protein localization and possibly in transmembrane anchoring and insertion.
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Affiliation(s)
- Jeffrey M Slack
- United State Department of Agriculture, Agriculture Research Service, Plant Sciences Institute, Insect Biocontrol Laboratory, Bldg 011A, Rm 214, BARC-West, Beltsville, MD 20705-2350, USA1
| | - Edward M Dougherty
- United State Department of Agriculture, Agriculture Research Service, Plant Sciences Institute, Insect Biocontrol Laboratory, Bldg 011A, Rm 214, BARC-West, Beltsville, MD 20705-2350, USA1
| | - Susan D Lawrence
- United State Department of Agriculture, Agriculture Research Service, Plant Sciences Institute, Insect Biocontrol Laboratory, Bldg 011A, Rm 214, BARC-West, Beltsville, MD 20705-2350, USA1
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Van Oers MM, Van Der Veken LT, Vlak JM, Thomas AA. Effect of baculovirus infection on the mRNA and protein levels of the Spodoptera frugiperda eukaryotic initiation factor 4E. INSECT MOLECULAR BIOLOGY 2001; 10:255-264. [PMID: 11437917 DOI: 10.1046/j.1365-2583.2001.00263.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The cDNA sequence of eukaryotic translation initiation factor eIF4E was derived from a Spodoptera frugiperda cDNA library. Eight tryptophan residues, typical for eIF4E, are strictly conserved in the encoded 210 amino acid protein. A polyclonal antiserum detected a 26 kDa protein in lepidopteran cell lines, but not in dipteran cells. Sf21 cells have a single eIF4E gene copy, which is transcribed into a 1500 nt transcript. Infection with AcMNPV resulted in a decrease in eIF4E mRNA starting between 12 and 24 h postinfection (p.i.), while reduced eIF4E protein levels were observed at 48 h p.i. Two forms of eIF4E were recognized that differed in their iso-electric point, of which the relative abundance did not change during infection. Mutagenesis experiments using recombinant baculoviruses revealed that the variation in mobility between these two forms did not result from a difference in the phosphorylation state of Ser-202, the serine residue that corresponds with the eIF4E phosphorylation site in mammalian eIF4E.
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Affiliation(s)
- M M Van Oers
- Laboratory of Virology, Wageningen University and Research Centre, Wageningen, The Netherlands.
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Lin G, Li G, Granados RR, Blissard GW. Stable cell lines expressing baculovirus P35: resistance to apoptosis and nutrient stress, and increased glycoprotein secretion. In Vitro Cell Dev Biol Anim 2001; 37:293-302. [PMID: 11513084 DOI: 10.1007/bf02577545] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The baculovirus P35 protein is a caspase inhibitor that prevents the induction of apoptosis during infection of Sf21 cells by Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV). P35 inhibits the induction of apoptosis in a broad range of cells and circumstances. In this study, we examined the effects of constitutive cellular P35 expression on the response of cells to stressful culture conditions and on protein production in AcMNPV infected cells. Sf9 cell lines expressing AcMNPV P35 or an epitope-tagged P35 protein were generated using a double selection technique, involving selection in the antibiotic G418, followed by a second round of selection by exposure to actinomycin D, a potent inducer of apoptosis in Sf9 cells. Clonal cell lines were generated and examined for (1) resistance to actinomycin D induced apoptosis, (2) resistance to nutrient deprivation, and (3) baculovirus expression of intracellular and secreted proteins. When compared with Sf9 cells, two P35-expressing cell lines (Sf9P35AcV5-1 and Sf9P35AcV5-3) showed increased resistance to actinomycin D-induced apoptosis and a profound resistance to nutrient deprivation. When these cell lines were infected with a recombinant baculovirus expressing a secreted glycoprotein (secreted alkaline phosphatase), expression of the glycoprotein from these cells exceeded that from the parental Sf9 cells and was comparable to expression levels obtained from Tn5B1-4 cells, the best available cell line for high-level expression. Increased levels of protein secretion in Sf9P35AcV5-1 and Sf9P35AcV5-3 cells appear to result from a prolonged infection cycle and accumulation of the secreted glycoprotein.
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Affiliation(s)
- G Lin
- Boyce Thompson Institute at Cornell University, Ithaca, New York 14853-1801, USA
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LIN GUANGYUN, LI GUOXUN, GRANADOS ROBERTR, BLISSARD GARYW. STABLE CELL LINES EXPRESSING BACULOVIRUS P35: RESISTANCE TO APOPTOSIS AND NUTRIENT STRESS, AND INCREASED GLYCOPROTEIN SECRETION. ACTA ACUST UNITED AC 2001. [DOI: 10.1290/1071-2690(2001)037<0293:sclebp>2.0.co;2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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