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Tan FH, Ng JF, Mohamed Alitheen NB, Muhamad A, Yong CY, Lee KW. A simple and high efficiency purification of His-tagged turnip yellow mosaic virus-like particle (TYMV-VLP) by nickel ion affinity precipitation. J Virol Methods 2023; 319:114771. [PMID: 37437780 DOI: 10.1016/j.jviromet.2023.114771] [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: 04/11/2023] [Revised: 07/05/2023] [Accepted: 07/08/2023] [Indexed: 07/14/2023]
Abstract
Virus-like particles (VLPs) is one of the most favourable subjects of study, especially in the field of nanobiotechnology and vaccine development because they possess good immunogenicity and self-adjuvant properties. Conventionally, VLPs can be tagged and purified using affinity chromatography or density gradient ultracentrifugation which is costly and time-consuming. Turnip yellow mosaic virus (TYMV) is a plant virus, where expression of the viral coat protein (TYMVc) in Escherichia coli (E. coli) has been shown to form VLP. In this study, we report a non-chromatographic method for VLP purification using C-terminally His-tagged TYMVc (TYMVcHis6) as a protein model. Firstly, the TYMVcHis6 was cloned and expressed in E. coli. Upon clarification of cell lysate, nickel (II) chloride [NiCl2; 15µM or equivalent to 0.0000194% (w/v)] was added to precipitate TYMVcHis6. Following centrifugation, the pellet was resuspended in buffer containing 1mM EDTA to chelate Ni2+, which is then removed via dialysis. A total of 50% of TYMVcHis6 was successfully recovered with purity above 0.90. Later, the purified TYMVcHis6 was analysed with sucrose density ultracentrifugation, dynamic light scattering (DLS), and transmission electron microscopy (TEM) to confirm VLP formation, which is comparable to TYMVcHis6 purified using the standard immobilized metal affinity chromatography (IMAC) column. As the current method omitted the need for IMAC column and beads while significantly reducing the time needed for column washing, nickel affinity precipitation represents a novel method for the purification of VLPs displaying poly-histidine tags (His-tags).
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Affiliation(s)
- Foo Hou Tan
- School of Biosciences, Faculty of Health and Medical Sciences, Taylor's University, Subang Jaya, Selangor, Malaysia
| | - Jeck Fei Ng
- School of Pharmacy, Faculty of Health and Medical Sciences, Taylor's University, Subang Jaya, Selangor, Malaysia
| | | | - Azira Muhamad
- Malaysia Genome and Vaccine Institute, National Institutes of Biotechnology Malaysia, Kajang, Selangor, Malaysia
| | - Chean Yeah Yong
- China-ASEAN College of Marine Sciences, Xiamen University Malaysia, Sepang, Selangor, Malaysia
| | - Khai Wooi Lee
- School of Biosciences, Faculty of Health and Medical Sciences, Taylor's University, Subang Jaya, Selangor, Malaysia.
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2
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Mahillon M, Brodard J, Kellenberger I, Blouin AG, Schumpp O. A novel weevil-transmitted tymovirus found in mixed infection on hollyhock. Virol J 2023; 20:17. [PMID: 36710353 PMCID: PMC9885571 DOI: 10.1186/s12985-023-01976-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 01/24/2023] [Indexed: 01/31/2023] Open
Abstract
Leaves of hollyhock (Alcea rosea) exhibiting vein chlorosis and yellow mosaic symptoms were collected at public sites in Lausanne and Nyon, two cities of western Switzerland. Diagnostic methods untangled in samples from both sites the mixed infections of a novel isometric virus, tentatively named "Alcea yellow mosaic virus" (AYMV) with the carlavirus Gaillardia latent virus. A new potyvirus was also identified in samples from Nyon. A combination of Illumina, Nanopore and Sanger sequencing was necessary to assemble the full-length genome of AYMV, revealing an exceptionally high cytidine content and other features typically associated with members of the genus Tymovirus. The host range of AYMV was found to be restricted to mallows, including ornamentals as well as economically important plants. Phylogenetic analyses further showed that AYMV belongs to a Tymovirus subclade that also gathers the other mallow-infecting members. The virus was readily transmitted by sap inoculation, and the weevil species Aspidapion radiolus was evidenced as a vector. Transmission assays using another weevil or other insect species did not succeed, and seed transmission was not observed.
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Affiliation(s)
- Mathieu Mahillon
- grid.417771.30000 0004 4681 910XResearch Group Virology, Bacteriology and Phytoplasmology, Agroscope, Nyon, Switzerland
| | - Justine Brodard
- grid.417771.30000 0004 4681 910XResearch Group Virology, Bacteriology and Phytoplasmology, Agroscope, Nyon, Switzerland
| | - Isabelle Kellenberger
- grid.417771.30000 0004 4681 910XResearch Group Virology, Bacteriology and Phytoplasmology, Agroscope, Nyon, Switzerland
| | - Arnaud G. Blouin
- grid.417771.30000 0004 4681 910XResearch Group Virology, Bacteriology and Phytoplasmology, Agroscope, Nyon, Switzerland
| | - Olivier Schumpp
- Research Group Virology, Bacteriology and Phytoplasmology, Agroscope, Nyon, Switzerland.
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3
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Ogrina A, Balke I, Kalnciema I, Skrastina D, Jansons J, Bachmann MF, Zeltins A. Bacterial expression systems based on Tymovirus-like particles for the presentation of vaccine antigens. Front Microbiol 2023; 14:1154990. [PMID: 37032851 PMCID: PMC10076540 DOI: 10.3389/fmicb.2023.1154990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 03/06/2023] [Indexed: 04/11/2023] Open
Abstract
Virus-like particles (VLPs) are virus-derived artificial nanostructures that resemble a native virus-stimulating immune system through highly repetitive surface structures. Improved safety profiles, flexibility in vaccine construction, and the ease of VLP production and purification have highlighted VLPs as attractive candidates for universal vaccine platform generation, although exploration of different types of expression systems for their development is needed. Here, we demonstrate the construction of several simple Escherichia coli expression systems for the generation of eggplant mosaic virus (EMV) VLP-derived vaccines. We used different principles of antigen incorporation, including direct fusion of EMV coat protein (CP) with major cat allergen Feld1, coexpression of antigen containing and unmodified (mosaic) EMV CPs, and two coexpression variants of EMV VLPs and antigen using synthetic zipper pair 18/17 (SYNZIP 18/17), and coiled-coil forming peptides E and K (Ecoil/Kcoil). Recombinant Fel d 1 chemically coupled to EMV VLPs was included as control experiments. All EMV-Feld1 variants were expressed in E. coli, formed Tymovirus-like VLPs, and were used for immunological evaluation in healthy mice. The immunogenicity of these newly developed vaccine candidates demonstrated high titers of Feld1-specific Ab production; however, a comparably high immune response against carrier EMV was also observed. Antibody avidity tests revealed very specific Ab production (more than 50% specificity) for four out of the five vaccine candidates. Native Feld1 recognition and subclass-specific antibody tests suggested that the EMV-SZ18/17-Feld1 complex and chemically coupled EMV-Feld1 vaccines may possess characteristics for further development.
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Affiliation(s)
- Anete Ogrina
- Latvian Biomedical Research and Study Centre, Riga, Latvia
| | - Ina Balke
- Latvian Biomedical Research and Study Centre, Riga, Latvia
| | - Ieva Kalnciema
- Latvian Biomedical Research and Study Centre, Riga, Latvia
| | - Dace Skrastina
- Latvian Biomedical Research and Study Centre, Riga, Latvia
| | - Juris Jansons
- Latvian Biomedical Research and Study Centre, Riga, Latvia
| | - Martin F. Bachmann
- Department of BioMedical Research, University of Bern, Bern, Switzerland
| | - Andris Zeltins
- Latvian Biomedical Research and Study Centre, Riga, Latvia
- *Correspondence: Andris Zeltins,
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Powell JD, Dreher TW. The generation of empty Turnip yellow mosaic virus capsids through depletion of virion-associated divalent cations. J Virol Methods 2022; 309:114595. [PMID: 35931228 DOI: 10.1016/j.jviromet.2022.114595] [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: 05/25/2022] [Revised: 07/28/2022] [Accepted: 08/01/2022] [Indexed: 12/24/2022]
Abstract
Turnip yellow mosaic virus (TYMV) is a well-studied icosahedral plant virus that has attractive properties for nanoscience applications. Stable empty particles devoid of viral genomic RNA have historically been generated from virions by: 1. high pressure; 2. extreme alkaline pH; and 3. freeze-thaw using liquid nitrogen. Herein we report a fourth and more convenient avenue for empty particle formation through EDTA treatment, implicating chelation of virion-associated cations. We present findings that confirm TYMV virions purified in an EDTA-based buffer are converted to 94 % empty on average during purification. Additional experimentation revealed TYMV virions purified through CsCl vs. sucrose gradients are more readily converted to empty particles after freeze thaw. These studies are novel as they show a purification method through EDTA-treatment that can generate stable empty particles devoid of viral genome. The convenience of this method should prove suitable for scientists seeking to use TYMV capsids in nanoscience-inspired applications. Importantly, these findings provide insight into historical discrepancies in creating empty particles after freeze-thaw, as the method in which TYMV virions are purified influences the downstream virion-to-empty conversion process.
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Affiliation(s)
- Joshua D Powell
- Department of Microbiology, Oregon State University, Corvallis, OR 97331, USA.
| | - Theo W Dreher
- Department of Microbiology, Oregon State University, Corvallis, OR 97331, USA
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Prakash DL, Gosavi S. The diversity of protein-protein interaction interfaces within T=3 icosahedral viral capsids. Front Mol Biosci 2022; 9:967877. [PMID: 36339706 PMCID: PMC9631432 DOI: 10.3389/fmolb.2022.967877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 09/08/2022] [Indexed: 11/20/2022] Open
Abstract
Some non-enveloped virus capsids assemble from multiple copies of a single type of coat-protein (CP). The comparative energetics of the diverse CP-CP interfaces present in such capsids likely govern virus assembly-disassembly mechanisms. The T = 3 icosahedral capsids comprise 180 CP copies arranged about two-, three-, five- and six-fold axes of (quasi-)rotation symmetry. Structurally diverse CPs can assemble into T = 3 capsids. Specifically, the Leviviridae CPs are structurally distinct from the Bromoviridae, Tombusviridae and Tymoviridae CPs which fold into the classic “jelly-roll” fold. However, capsids from across the four families are known to disassemble into dimers. To understand whether the overall symmetry of the capsid or the structural details of the CP determine virus assembly-disassembly mechanisms, we analyze the different CP-CP interfaces that occur in the four virus families. Previous work studied protein homodimer interfaces using interface size (relative to the monomer) and hydrophobicity. Here, we analyze all CP-CP interfaces using these two parameters and find that the dimerization interface (present between two CPs congruent through a two-fold axis of rotation) has a larger relative size in the Leviviridae than in the other viruses. The relative sizes of the other Leviviridae interfaces and all the jelly-roll interfaces are similar. However, the dimerization interfaces across families have slightly higher hydrophobicity, potentially making them stronger than other interfaces. Finally, although the CP-monomers of the jelly-roll viruses are structurally similar, differences in their dimerization interfaces leads to varied dimer flexibility. Overall, differences in CP-structures may induce different modes of swelling and assembly-disassembly in the T = 3 viruses.
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6
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Tan FH, Kong JC, Ng JF, Alitheen NB, Wong CL, Yong CY, Lee KW. Recombinant turnip yellow mosaic virus coat protein as a potential nanocarrier. J Appl Microbiol 2021; 131:2072-2080. [PMID: 33629458 DOI: 10.1111/jam.15048] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 02/17/2021] [Accepted: 02/19/2021] [Indexed: 01/13/2023]
Abstract
AIMS To display a short peptide (GSRSHHHHHH) at the C-terminal end of turnip yellow mosaic virus coat protein (TYMVc) and to study its assembly into virus-like particles (TYMVcHis6 VLPs). METHODS AND RESULTS In this study, recombinant TYMVcHis6 expressed in Escherichia coli self-assembled into VLPs of approximately 30-32 nm. SDS-PAGE and Western blot analysis of protein fractions from the immobilized metal affinity chromatography (IMAC) showed that TYMVcHis6 VLPs interacted strongly with nickel ligands in IMAC column, suggesting that the fusion peptide is protruding out from the surface of VLPs. These VLPs are highly stable over a wide pH range from 3·0 to 11·0 at different temperatures. At pH 11·0, specifically, the VLPs remained intact up to 75°C. Additionally, the disassembly and reassembly of TYMVcHis6 VLPs were studied in vitro. Dynamic light scattering and transmission electron microscopy analysis revealed that TYMVcHis6 VLPs were dissociated by 7 mol l-1 urea and 2 mol l-1 guanidine hydrochloride (GdnHCl) without impairing their reassembly property. CONCLUSIONS A 10-residue peptide was successfully displayed on the surface of TYMVcHis6 VLPs. This chimera demonstrated high stability under extreme thermal conditions with varying pH and was able to dissociate and reassociate into VLPs by chemical denaturants. SIGNIFICANCE AND IMPACT OF THE STUDY This is the first C-terminally modified TYMVc produced in E. coli. The C-terminal tail which is exposed on the surface can be exploited as a useful site to display multiple copies of functional ligands. The ability of the chimeric VLPs to self-assemble after undergo chemical denaturation indicates its potential role to serve as a nanocarrier for use in targeted drug delivery.
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Affiliation(s)
- F H Tan
- School of Biosciences, Faculty of Health and Medical Sciences, Taylor's University, Subang Jaya, Selangor, Malaysia
| | - J C Kong
- School of Biosciences, Faculty of Health and Medical Sciences, Taylor's University, Subang Jaya, Selangor, Malaysia
| | - J F Ng
- School of Biosciences, Faculty of Health and Medical Sciences, Taylor's University, Subang Jaya, Selangor, Malaysia
| | - N B Alitheen
- Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - C L Wong
- Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - C Y Yong
- Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - K W Lee
- School of Biosciences, Faculty of Health and Medical Sciences, Taylor's University, Subang Jaya, Selangor, Malaysia
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7
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Vasques RM, Correa RFT, da Silva LA, Blawid R, Nagata T, Ribeiro BM, Ardisson-Araújo DMP. Assembly of tomato blistering mosaic virus-like particles using a baculovirus expression vector system. Arch Virol 2019; 164:1753-1760. [PMID: 31025116 DOI: 10.1007/s00705-019-04262-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 03/27/2019] [Indexed: 01/23/2023]
Abstract
The expression of several structural proteins from a wide variety of viruses in heterologous cell culture systems results in the formation of virus-like particles (VLPs). These VLPs structurally resemble the wild-type virus particles and have been used to study viral assembly process and as antigens for diagnosis and/or vaccine development. Tomato blistering mosaic virus (ToBMV) is a tymovirus that has a 6.3-kb positive-sense ssRNA genome. We have employed the baculovirus expression vector system (BEVS) for the production of tymovirus-like particles (tVLPs) in insect cells. Two recombinant baculoviruses containing the ToBMV wild-type coat protein (CP) gene or a modified short amino-terminal deletion (Δ2-24CP) variant were constructed and used to infect insect cells. Both recombinant viruses were able to express ToBMV CP and Δ2-24CP from infected insect cells that self-assembled into tVLPs. Therefore, the N-terminal residues (2-24) of the native ToBMV CP were shown not to be essential for self-assembly of tVLPs. We also constructed a third recombinant baculovirus containing a small sequence coding for the major epitope of the chikungunya virus (CHIKV) envelope protein 2 (E2) replacing the native CP N-terminal 2-24 amino acids. This recombinant virus also produced tVLPs. In summary, ToBMV VLPs can be produced in a baculovirus/insect cell heterologous expression system, and the N-terminal residues 2-24 of the CP are not essential for this assembly, allowing its potential use as a protein carrier that facilitates antigen purification and might be used for diagnosis.
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Affiliation(s)
- Raquel Medeiros Vasques
- Laboratory of Microscopy and Virology, Cell Biology Department, University of Brasilia, Brasília, DF, Brazil
- Laboratory of Baculovirus, Cell Biology Department, University of Brasilia, Brasília, DF, Brazil
| | | | - Leonardo Assis da Silva
- Laboratory of Baculovirus, Cell Biology Department, University of Brasilia, Brasília, DF, Brazil
| | - Rosana Blawid
- Laboratory of Phytovirology, Department of Agronomy, Rural Federal University of Pernambuco, Recife, PE, Brazil
| | - Tatsuya Nagata
- Laboratory of Microscopy and Virology, Cell Biology Department, University of Brasilia, Brasília, DF, Brazil
| | - Bergmann Morais Ribeiro
- Laboratory of Baculovirus, Cell Biology Department, University of Brasilia, Brasília, DF, Brazil
| | - Daniel M P Ardisson-Araújo
- Laboratory of Insect Virology, Department of Biochemistry and Molecular Biology, Federal University of Santa Maria, Santa Maria, RS, 97105-900, Brazil.
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8
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Matsuura K. Synthetic approaches to construct viral capsid-like spherical nanomaterials. Chem Commun (Camb) 2018; 54:8944-8959. [DOI: 10.1039/c8cc03844a] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This feature article describes recent progress in synthetic strategies to construct viral capsid-like spherical nanomaterials using the self-assembly of peptides and/or proteins.
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Affiliation(s)
- Kazunori Matsuura
- Department of Chemistry and Biotechnology
- Graduate School of Engineering
- Tottori University
- Tottori 680-8552
- Japan
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Matsuura K, Mizuguchi Y, Kimizuka N. Peptide nanospheres self-assembled from a modified β
-annulus peptide of Sesbania mosaic virus. Biopolymers 2016; 106:470-5. [DOI: 10.1002/bip.22774] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 10/15/2015] [Accepted: 11/02/2015] [Indexed: 12/12/2022]
Affiliation(s)
- Kazunori Matsuura
- Department of Chemistry and Biotechnology, Graduate School of Engineering; Tottori University; Tottori Japan
| | - Yusaku Mizuguchi
- Department of Chemistry and Biochemistry, Graduate School of Engineering; Kyushu University; Fukuoka Japan
| | - Nobuo Kimizuka
- Department of Chemistry and Biochemistry, Graduate School of Engineering; Kyushu University; Fukuoka Japan
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Chae KH, Kim D, Cho TJ. N-terminal Extension of Coat Protein of Turnip Yellow Mosaic Virus has Variable Effects on Replication, RNA Packaging, and Virion Assembly Depending on the Inserted Sequence. ACTA ACUST UNITED AC 2016. [DOI: 10.4167/jbv.2016.46.1.13] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Kwang-Hee Chae
- Department of Biochemistry, Chungbuk National University, Cheongju, Korea
| | - Doyeong Kim
- Department of Biochemistry, Chungbuk National University, Cheongju, Korea
| | - Tae-Ju Cho
- Department of Biochemistry, Chungbuk National University, Cheongju, Korea
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11
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Blawid R, Nagata T. Construction of an infectious clone of a plant RNA virus in a binary vector using one-step Gibson Assembly. J Virol Methods 2015; 222:11-5. [PMID: 25986144 DOI: 10.1016/j.jviromet.2015.05.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 05/06/2015] [Accepted: 05/07/2015] [Indexed: 11/29/2022]
Abstract
The construction of full-length infectious clones of RNA viruses is often laborious due to the many cloning steps required and the DNA exclusion within the plasmid during Escherichia coli transformation. We demonstrate single-step cloning procedure of an infectious cDNA of the tomato blistering mosaic virus (ToBMV) using Gibson Assembly (GA), which drastically reduces the number of cloning steps. By agro-inoculation with the construct obtained by this procedure, ToBMV was recovered six days post-inoculation in Nicotiana benthamiana plants. The symptoms induced by the recovered virus were indistinguishable from those caused by the wild-type virus. We conclude that the GA is very useful method particularly to construct a full-length cDNA clone of a plant RNA virus in a binary vector.
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Affiliation(s)
- Rosana Blawid
- Universidade de Brasília, Department of Cell Biology, Campus Universitário Darcy Ribeiro, 70910-900 Brasília, DF, Brazil
| | - Tatsuya Nagata
- Universidade de Brasília, Department of Cell Biology, Campus Universitário Darcy Ribeiro, 70910-900 Brasília, DF, Brazil.
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Natilla A, Murphy C, Hammond RW. Mutations in the alpha-helical region of the amino terminus of the Maize rayado fino virus capsid protein and CP:RNA ratios affect virus-like particle encapsidation of RNAs. Virus Res 2015; 196:70-8. [PMID: 25102332 DOI: 10.1016/j.virusres.2014.07.033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Revised: 07/24/2014] [Accepted: 07/26/2014] [Indexed: 11/25/2022]
Abstract
Viral-based nanoplatforms rely on balancing the delicate array of virus properties to optimally achieve encapsidation of foreign materials with various potential objectives. We investigated the use of Maize rayado fino virus (MRFV)-virus-like particles (VLPs) as a multifunctional nanoplatform and their potential application as protein cages. MRFV-VLPs are composed of two serologically related, carboxy co-terminal coat proteins (CP1 and CP2) which are capable of self-assembling in Nicotiana benthamiana plants into 30nm particles with T=3 symmetry. The N-terminus of CP1 was targeted for genetic modification to exploit the driving forces for VLP assembly, packaging and retention of RNA in vivo and in vitro. The N-terminus of MRFV-CP1 contains a peptide sequence of 37 amino acids which has been predicted to have an alpha-helical structure, is rich in hydrophobic amino acids, facilitates CP-RNA interactions, and is not required for self-assembly. Amino acid substitutions were introduced in the 37 amino acid N-terminus by site-directed mutagenesis and the mutant VLPs produced in plants by a Potato virus X (PVX)-based vector were tested for particle stability and RNA encapsidation. All mutant CPs resulted in production of VLPs which encapsidated non-viral RNAs, including PVX genomic and subgenomic (sg) RNAs, 18S rRNA and cellular and viral mRNAs. In addition, MRFV-VLPs encapsidated GFP mRNA when was expressed in plant cells from the pGD vector. These results suggest that RNA packaging in MRFV-VLPs is predominantly driven by electrostatic interactions between the N-terminal 37 amino acid extension of CP1 and RNA, and that the overall species concentration of RNA in the cellular pool may determine the abundance and species of the RNAs packaged into the VLPs. Furthermore, RNA encapsidation is not required for VLPs stability, VLPs formed from MRFV-CP1 were stable at temperatures up to 70°C, and can be disassembled into CP monomers, which can then reassemble in vitro into complete VLPs either in the absence or presence of RNAs.
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Affiliation(s)
- Angela Natilla
- United States Department of Agriculture, Beltsville Agricultural Research Service, Molecular Plant Pathology Laboratory, Beltsville, MD 20705, United States.
| | - Charles Murphy
- United States Department of Agriculture, Beltsville Agricultural Research Service, Electron and Confocal Microscopy Unit, Beltsville, MD 20705, United States
| | - Rosemarie W Hammond
- United States Department of Agriculture, Beltsville Agricultural Research Service, Molecular Plant Pathology Laboratory, Beltsville, MD 20705, United States
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Niu S, Gil-Salas FM, Tewary SK, Samales AK, Johnson J, Swaminathan K, Wong SM. Hibiscus chlorotic ringspot virus coat protein is essential for cell-to-cell and long-distance movement but not for viral RNA replication. PLoS One 2014; 9:e113347. [PMID: 25402344 PMCID: PMC4234673 DOI: 10.1371/journal.pone.0113347] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Accepted: 10/22/2014] [Indexed: 11/29/2022] Open
Abstract
Hibiscus chlorotic ringspot virus (HCRSV) is a member of the genus Carmovirus in the family Tombusviridae. In order to study its coat protein (CP) functions on virus replication and movement in kenaf (Hibiscus cannabinus L.), two HCRSV mutants, designated as p2590 (A to G) in which the first start codon ATG was replaced with GTG and p2776 (C to G) in which proline 63 was replaced with alanine, were constructed. In vitro transcripts of p2590 (A to G) were able to replicate to a similar level as wild type without CP expression in kenaf protoplasts. However, its cell-to-cell movement was not detected in the inoculated kenaf cotyledons. Structurally the proline 63 in subunit C acts as a kink for β-annulus formation during virion assembly. Progeny of transcripts derived from p2776 (C to G) was able to move from cell-to-cell in inoculated cotyledons but its long-distance movement was not detected. Virions were not observed in partially purified mutant virus samples isolated from 2776 (C to G) inoculated cotyledons. Removal of the N-terminal 77 amino acids of HCRSV CP by trypsin digestion of purified wild type HCRSV virions resulted in only T = 1 empty virus-like particles. Taken together, HCRSV CP is dispensable for viral RNA replication but essential for cell-to-cell movement, and virion is required for the virus systemic movement. The proline 63 is crucial for HCRSV virion assembly in kenaf plants and the N-terminal 77 amino acids including the β-annulus domain is required in T = 3 assembly in vitro.
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Affiliation(s)
- Shengniao Niu
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
- Key Laboratory of Tropical Crop Biotechnology, Ministry of Agriculture, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Science, Hainan, China
| | - Francisco M. Gil-Salas
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
- Instituto Andaluz de Investigación y Formación Agraria, Pesquera, Alimentaria y de la Producción Ecológica, Almería, Spain
| | - Sunil Kumar Tewary
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | | | - John Johnson
- Department of Molecular Biology, The Scripps Research Institute, California, United States of America
| | | | - Sek-Man Wong
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
- Temasek Life Sciences Laboratory, Singapore, Singapore
- National University of Singapore Suzhou Research Institute, Suzhou Industrial Park, Jiangsu, China
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14
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Polyvalent display of RGD motifs on turnip yellow mosaic virus for enhanced stem cell adhesion and spreading. Acta Biomater 2012; 8:2978-85. [PMID: 22522012 DOI: 10.1016/j.actbio.2012.04.027] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Revised: 04/11/2012] [Accepted: 04/12/2012] [Indexed: 11/22/2022]
Abstract
Turnip yellow mosaic virus (TYMV) is a stable 28 nm icosahedral plant virus that can be isolated in gram quantities. In order to study the polyvalent effect of Arg-Gly-Asp (RGD) clustering on the response of bone marrow stem cells (BMSCs), an RGD motif was genetically displayed on the coat protein of the TYMV capsid. Composite films composed of either wild-type TYMV or TYMV-RGD44, in combination with poly(allylamine hydrochloride) (PAH), were fabricated by a layer-by-layer adsorption of virus and PAH. The deposition process was studied by quartz crystal microbalance, UV-visible spectroscopy and atomic force microscopy. BMSC adhesion assays showed enhanced cell adhesion and spreading on TYMV-RGD44 coated substrates compared to native TYMV. These results demonstrate the potential of TYMV as a viable scaffold for bioactive peptide display and cell culturing studies.
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