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Hardy J, Demecheleer E, Schauvliege M, Staelens D, Mortier V, Verhofstede C. Reverse transcription of plasma-derived HIV-1 RNA generates multiple artifacts through tRNA(Lys-3)-priming. Microbiol Spectr 2024; 12:e0387223. [PMID: 38442427 PMCID: PMC10986323 DOI: 10.1128/spectrum.03872-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Accepted: 02/05/2024] [Indexed: 03/07/2024] Open
Abstract
In vitro reverse transcription of full-length HIV-1 RNA extracted from the blood plasma of people living with HIV-1 remains challenging. Here, we describe the initiation of reverse transcription of plasma-derived viral RNA in the absence of an exogenous primer. Real-time PCR and Sanger sequencing were applied to identify the source and to monitor the outcome of this reaction. Results demonstrated that during purification of viral RNA from plasma, tRNA(Lys-3) is co-extracted in a complex with the viral RNA. In the presence of a reverse transcription enzyme, this tRNA(Lys-3) can induce reverse transcription, a reaction that is not confined to transcription of the 5' end of the viral RNA. A range of cDNA products is generated, most of them indicative for the occurrence of in vitro strand transfer events that involve translocation of cDNA from the 5' end to random positions on the viral RNA. This process results in the formation of cDNAs with large internal deletions. However, near full-length cDNA and cDNA with sequence patterns resembling multiple spliced HIV-1 RNA were also detected. Despite its potential to introduce significant bias in the interpretation of results across various applications, tRNA(Lys-3)-driven reverse transcription has been overlooked thus far. A more in-depth study of this tRNA-driven in vitro reaction may provide new insight into the complex process of in vivo HIV-1 replication.IMPORTANCEThe use of silica-based extraction methods for purifying HIV-1 RNA from viral particles is a common practice, but it involves co-extraction of human tRNA(Lys-3) due to the strong interactions between these molecules. This co-extraction becomes particularly significant when the extracted RNA is used in reverse transcription reactions, as the tRNA(Lys-3) then serves as a primer. Reverse transcription from tRNA(Lys-3) is not confined to cDNA synthesis of the 5' end of the viral RNA but extends across various regions of the viral genome through in vitro strand transfer events. Co-extraction of tRNA(Lys-3) has been overlooked thus far, despite its potential to introduce bias in downstream, reverse transcription-related applications. The observed events in the tRNA(Lys-3)-induced in vitro reverse transcription resemble in vivo replication processes. Therefore, these reactions may offer a unique model to better understand the replication dynamics of HIV-1.
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Affiliation(s)
- Jarryt Hardy
- Aids Reference Laboratory, Department of Diagnostic Sciences, Ghent University, Ghent, Belgium
| | - Els Demecheleer
- Aids Reference Laboratory, Department of Diagnostic Sciences, Ghent University, Ghent, Belgium
| | - Marlies Schauvliege
- Aids Reference Laboratory, Department of Diagnostic Sciences, Ghent University, Ghent, Belgium
| | - Delfien Staelens
- Aids Reference Laboratory, Department of Diagnostic Sciences, Ghent University, Ghent, Belgium
| | - Virginie Mortier
- Aids Reference Laboratory, Department of Diagnostic Sciences, Ghent University, Ghent, Belgium
| | - Chris Verhofstede
- Aids Reference Laboratory, Department of Diagnostic Sciences, Ghent University, Ghent, Belgium
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Tang Y, Behrens RT, St Gelais C, Wu S, Vivekanandan S, Razin E, Fang P, Wu L, Sherer N, Musier-Forsyth K. Human lysyl-tRNA synthetase phosphorylation promotes HIV-1 proviral DNA transcription. Nucleic Acids Res 2023; 51:12111-12123. [PMID: 37933844 PMCID: PMC10711549 DOI: 10.1093/nar/gkad941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 09/18/2023] [Accepted: 10/11/2023] [Indexed: 11/08/2023] Open
Abstract
Human lysyl-tRNA synthetase (LysRS) was previously shown to be re-localized from its normal cytoplasmic location in a multi-aminoacyl-tRNA synthetase complex (MSC) to the nucleus of HIV-1 infected cells. Nuclear localization depends on S207 phosphorylation but the nuclear function of pS207-LysRS in the HIV-1 lifecycle is unknown. Here, we show that HIV-1 replication was severely reduced in a S207A-LysRS knock-in cell line generated by CRISPR/Cas9; this effect was rescued by S207D-LysRS. LysRS phosphorylation up-regulated HIV-1 transcription, as did direct transfection of Ap4A, an upstream transcription factor 2 (USF2) activator that is synthesized by pS207-LysRS. Overexpressing an MSC-derived peptide known to stabilize LysRS MSC binding inhibited HIV-1 replication. Transcription of HIV-1 proviral DNA and other USF2 target genes was reduced in peptide-expressing cells. We propose that nuclear pS207-LysRS generates Ap4A, leading to activation of HIV-1 transcription. Our results suggest a new role for nuclear LysRS in facilitating HIV-1 replication and new avenues for antiviral therapy.
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Affiliation(s)
- Yingke Tang
- Department of Chemistry and Biochemistry, Ohio State University, Columbus, OH, USA
- Center for Retrovirus Research, Ohio State University, Columbus, OH, USA
- Center for RNA Biology, Ohio State University, Columbus, OH, USA
| | - Ryan T Behrens
- McArdle Laboratory for Cancer Research, Institute for Molecular Virology, & Carbone Cancer Center, University of Wisconsin, Madison, WI, USA
| | - Corine St Gelais
- Center for Retrovirus Research, Ohio State University, Columbus, OH, USA
- Center for RNA Biology, Ohio State University, Columbus, OH, USA
- Department of Veterinary Biosciences, Ohio State University, Columbus, OH, USA
| | - Siqi Wu
- State Key Laboratory of Chemical Biology, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, China
| | - Saravanan Vivekanandan
- Cellular and Molecular Mechanisms of Inflammation Program, National University of Singapore and The Hebrew University of Jerusalem (NUS–HUJ), Singapore
| | - Ehud Razin
- Department of Biochemistry and Molecular Biology, Institute for Medical Research Israel-Canada, The Hebrew University of Jerusalem, Israel
| | - Pengfei Fang
- State Key Laboratory of Chemical Biology, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, China
| | - Li Wu
- Department of Microbiology and Immunology, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Nathan Sherer
- McArdle Laboratory for Cancer Research, Institute for Molecular Virology, & Carbone Cancer Center, University of Wisconsin, Madison, WI, USA
| | - Karin Musier-Forsyth
- Department of Chemistry and Biochemistry, Ohio State University, Columbus, OH, USA
- Center for Retrovirus Research, Ohio State University, Columbus, OH, USA
- Center for RNA Biology, Ohio State University, Columbus, OH, USA
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Hein MD, Kazenmaier D, van Heuvel Y, Dogra T, Cattaneo M, Kupke SY, Stitz J, Genzel Y, Reichl U. Production of retroviral vectors in continuous high cell density culture. Appl Microbiol Biotechnol 2023; 107:5947-5961. [PMID: 37542575 PMCID: PMC10485120 DOI: 10.1007/s00253-023-12689-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 07/06/2023] [Accepted: 07/12/2023] [Indexed: 08/07/2023]
Abstract
Retroviral vectors derived from murine leukemia virus (MLV) are used in somatic gene therapy applications e.g. for genetic modification of hematopoietic stem cells. Recently, we reported on the establishment of a suspension viral packaging cell line (VPC) for the production of MLV vectors. Human embryonic kidney 293-F (HEK293-F) cells were genetically modified for this purpose using transposon vector technology. Here, we demonstrate the establishment of a continuous high cell density (HCD) process using this cell line. First, we compared different media regarding the maximum achievable viable cell concentration (VCC) in small scale. Next, we transferred this process to a stirred tank bioreactor before we applied intensification strategies. Specifically, we established a perfusion process using an alternating tangential flow filtration system. Here, VCCs up to 27.4E + 06 cells/mL and MLV vector titers up to 8.6E + 06 transducing units/mL were achieved. Finally, we established a continuous HCD process using a tubular membrane for cell retention and continuous viral vector harvesting. Here, the space-time yield was 18-fold higher compared to the respective batch cultivations. Overall, our results clearly demonstrate the feasibility of HCD cultivations for high yield production of viral vectors, especially when combined with continuous viral vector harvesting. KEY POINTS: • A continuous high cell density process for MLV vector production was established • The tubular cell retention membrane allowed for continuous vector harvesting • The established process had a 18-fold higher space time yield compared to a batch.
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Affiliation(s)
- Marc D Hein
- Chair of Bioprocess Engineering, Otto-Von-Guericke-University Magdeburg, Magdeburg, Germany
| | - Daniel Kazenmaier
- Bioprocess Engineering, Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany
- Faculty of Biotechnology, University of Applied Sciences Mannheim, Mannheim, Germany
| | - Yasemin van Heuvel
- Faculty of Applied Natural Sciences, University of Applied Sciences Cologne, Leverkusen, Germany
- Institute of Technical Chemistry, Leibniz University Hannover, Hannover, Germany
| | - Tanya Dogra
- Bioprocess Engineering, Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany
| | | | - Sascha Y Kupke
- Bioprocess Engineering, Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany
| | - Jörn Stitz
- Faculty of Applied Natural Sciences, University of Applied Sciences Cologne, Leverkusen, Germany
| | - Yvonne Genzel
- Bioprocess Engineering, Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany.
| | - Udo Reichl
- Chair of Bioprocess Engineering, Otto-Von-Guericke-University Magdeburg, Magdeburg, Germany
- Bioprocess Engineering, Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany
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Kaddis Maldonado R, Lambert GS, Rice BL, Sudol M, Flanagan JM, Parent LJ. The Rous sarcoma virus Gag Polyprotein Forms Biomolecular Condensates Driven by Intrinsically-disordered Regions. J Mol Biol 2023; 435:168182. [PMID: 37328094 PMCID: PMC10527454 DOI: 10.1016/j.jmb.2023.168182] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 06/07/2023] [Accepted: 06/09/2023] [Indexed: 06/18/2023]
Abstract
Biomolecular condensates (BMCs) play important roles incellular structures includingtranscription factories, splicing speckles, and nucleoli. BMCs bring together proteins and other macromolecules, selectively concentrating them so that specific reactions can occur without interference from the surrounding environment. BMCs are often made up of proteins that contain intrinsically disordered regions (IDRs), form phase-separated spherical puncta, form liquid-like droplets that undergo fusion and fission, contain molecules that are mobile, and are disrupted with phase-dissolving drugs such as 1,6-hexanediol. In addition to cellular proteins, many viruses, including influenza A, SARS-CoV-2, and human immunodeficiency virus type 1 (HIV-1) encode proteins that undergo phase separation and rely on BMC formation for replication. In prior studies of the retrovirus Rous sarcoma virus (RSV), we observed that the Gag protein forms discrete spherical puncta in the nucleus, cytoplasm, and at the plasma membrane that co-localize with viral RNA and host factors, raising the possibility that RSV Gag forms BMCs that participate in the intracellular phase of the virion assembly pathway. In our current studies, we found that Gag contains IDRs in the N-terminal (MAp2p10) and C-terminal (NC) regions of the protein and fulfills many criteria of BMCs. Although the role of BMC formation in RSV assembly requires further study, our results suggest the biophysical properties of condensates are required for the formation of Gag complexes in the nucleus and the cohesion of these complexes as they traffic through the nuclear pore, into the cytoplasm, and to the plasma membrane, where the final assembly and release of virus particles occurs.
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Affiliation(s)
- Rebecca Kaddis Maldonado
- Department of Medicine, Penn State College of Medicine, 500 University Drive, Hershey, PA 17033, USA; Department of Microbiology & Immunology, Penn State College of Medicine, 500 University Drive, Hershey, PA 17033, USA
| | - Gregory S Lambert
- Department of Medicine, Penn State College of Medicine, 500 University Drive, Hershey, PA 17033, USA
| | - Breanna L Rice
- Department of Medicine, Penn State College of Medicine, 500 University Drive, Hershey, PA 17033, USA
| | - Malgorzata Sudol
- Department of Medicine, Penn State College of Medicine, 500 University Drive, Hershey, PA 17033, USA
| | - John M Flanagan
- Department of Biochemistry & Molecular Biology, Penn State College of Medicine, 500 University Drive, Hershey, PA 17033, USA
| | - Leslie J Parent
- Department of Medicine, Penn State College of Medicine, 500 University Drive, Hershey, PA 17033, USA; Department of Microbiology & Immunology, Penn State College of Medicine, 500 University Drive, Hershey, PA 17033, USA.
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Sibarov DA, Tsytsarev V, Volnova A, Vaganova AN, Alves J, Rojas L, Sanabria P, Ignashchenkova A, Savage ED, Inyushin M. Arc protein, a remnant of ancient retrovirus, forms virus-like particles, which are abundantly generated by neurons during epileptic seizures, and affects epileptic susceptibility in rodent models. Front Neurol 2023; 14:1201104. [PMID: 37483450 PMCID: PMC10361770 DOI: 10.3389/fneur.2023.1201104] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 06/02/2023] [Indexed: 07/25/2023] Open
Abstract
A product of the immediate early gene Arc (Activity-regulated cytoskeleton-associated protein or Arc protein) of retroviral ancestry resides in the genome of all tetrapods for millions of years and is expressed endogenously in neurons. It is a well-known protein, very important for synaptic plasticity and memory consolidation. Activity-dependent Arc expression concentrated in glutamatergic synapses affects the long-time synaptic strength of those excitatory synapses. Because it modulates excitatory-inhibitory balance in a neuronal network, the Arc gene itself was found to be related to the pathogenesis of epilepsy. General Arc knockout rodent models develop a susceptibility to epileptic seizures. Because of activity dependence, synaptic Arc protein synthesis also is affected by seizures. Interestingly, it was found that Arc protein in synapses of active neurons self-assemble in capsids of retrovirus-like particles, which can transfer genetic information between neurons, at least across neuronal synaptic boutons. Released Arc particles can be accumulated in astrocytes after seizures. It is still not known how capsid assembling and transmission timescale is affected by seizures. This scientific field is relatively novel and is experiencing swift transformation as it grapples with difficult concepts in light of evolving experimental findings. We summarize the emergent literature on the subject and also discuss the specific rodent models for studying Arc effects in epilepsy. We summarized both to clarify the possible role of Arc-related pseudo-viral particles in epileptic disorders, which may be helpful to researchers interested in this growing area of investigation.
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Affiliation(s)
- Dmitry A. Sibarov
- Sechenov Institute of Evolutionary Physiology and Biochemistry of the Russian Academy of Sciences, Saint Petersburg, Russia
| | - Vassiliy Tsytsarev
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Anna Volnova
- Institute of Translational Biomedicine, Saint Petersburg State University, Saint Petersburg, Russia
| | - Anastasia N. Vaganova
- Institute of Translational Biomedicine, Saint Petersburg State University, Saint Petersburg, Russia
| | - Janaina Alves
- School of Medicine, Universidad Central del Caribe, Bayamón, PR, United States
| | - Legier Rojas
- School of Medicine, Universidad Central del Caribe, Bayamón, PR, United States
| | - Priscila Sanabria
- School of Medicine, Universidad Central del Caribe, Bayamón, PR, United States
| | | | | | - Mikhail Inyushin
- School of Medicine, Universidad Central del Caribe, Bayamón, PR, United States
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6
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Longitudinal characterization of circulating extracellular vesicles and small RNA during simian immunodeficiency virus infection and antiretroviral therapy. AIDS 2023; 37:733-744. [PMID: 36779477 PMCID: PMC9994802 DOI: 10.1097/qad.0000000000003487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
OBJECTIVES Latent infection by HIV hinders viral eradication despite effective antiretroviral treatment (ART). Among proposed contributors to viral latency are cellular small RNAs that have also been proposed to shuttle between cells in extracellular vesicles. Thus, we profiled extracellular vesicle small RNAs during different infection phases to understand the potential relationship between these extracellular vesicle associated small RNAs and viral infection. DESIGN A well characterized simian immunodeficiency virus (SIV)/macaque model of HIV was used to profile extracellular vesicle enriched blood plasma fractions harvested during preinfection, acute infection, latent infection/ART treatment, and rebound after ART interruption. METHODS Measurement of extracellular vesicle concentration, size distribution, and morphology was complemented with qPCR array for small RNA expression, followed by individual qPCR validations. Iodixanol density gradients were used to separate extracellular vesicle subtypes and virions. RESULTS Plasma extracellular vesicle particle counts correlated with viral load and peaked during acute infection. However, SIV gag RNA detection showed that virions did not fully explain this peak. Extracellular vesicle microRNAs miR-181a, miR-342-3p, and miR-29a decreased with SIV infection and remained downregulated in latency. Interestingly, small nuclear RNA U6 had a tight association with viral load peak. CONCLUSION This study is the first to monitor how extracellular vesicle concentration and extracellular vesicle small RNA expression change dynamically in acute viral infection, latency, and rebound in a carefully controlled animal model. These changes may also reveal regulatory roles in retroviral infection and latency.
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van Heuvel Y, Schatz S, Hein M, Dogra T, Kazenmaier D, Tschorn N, Genzel Y, Stitz J. Novel suspension retroviral packaging cells generated by transposition using transposase encoding mRNA advance vector yields and enable production in bioreactors. Front Bioeng Biotechnol 2023; 11:1076524. [PMID: 37082212 PMCID: PMC10112512 DOI: 10.3389/fbioe.2023.1076524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 03/24/2023] [Indexed: 04/22/2023] Open
Abstract
To date, the establishment of high-titer stable viral packaging cells (VPCs) at large scale for gene therapeutic applications is very time- and cost-intensive. Here we report the establishment of three human suspension 293-F-derived ecotropic MLV-based VPCs. The classic stable transfection of an EGFP-expressing transfer vector resulted in a polyclonal VPC pool that facilitated cultivation in shake flasks of 100 mL volumes and yielded high functional titers of more than 1 × 106 transducing units/mL (TU/mL). When the transfer vector was flanked by transposon terminal inverted repeats (TIRs) and upon co-transfection of a plasmid encoding for the transposase, productivities could be slightly elevated to more than 3 × 106 TU/mL. In contrast and using mRNA encoding for the transposase, as a proof of concept, productivities were drastically improved by more than ten-fold exceeding 5 × 107 TU/mL. In addition, these VPC pools were generated within only 3 weeks. The production volume was successfully scaled up to 500 mL employing a stirred-tank bioreactor (STR). We anticipate that the stable transposition of transfer vectors employing transposase transcripts will be of utility for the future establishment of high-yield VPCs producing pseudotype vector particles with a broader host tropism on a large scale.
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Affiliation(s)
- Yasemin van Heuvel
- Research Group Medical Biotechnology and Bioengineering, Faculty of Applied Natural Sciences, University of Applied Sciences Cologne, Campus Leverkusen, Cologne, Germany
- Institute of Technical Chemistry, Gottfried Wilhelm Leibniz University Hannover, Hanover, Germany
| | - Stefanie Schatz
- Research Group Medical Biotechnology and Bioengineering, Faculty of Applied Natural Sciences, University of Applied Sciences Cologne, Campus Leverkusen, Cologne, Germany
- Institute of Technical Chemistry, Gottfried Wilhelm Leibniz University Hannover, Hanover, Germany
| | - Marc Hein
- Chair of Bioprocess Engineering, Otto-Von-Guericke-University Magdeburg, Magdeburg, Germany
- Max Planck Institute for Dynamics of Complex Technical Systems, Bioprocess Engineering, Magdeburg, Germany
| | - Tanya Dogra
- Max Planck Institute for Dynamics of Complex Technical Systems, Bioprocess Engineering, Magdeburg, Germany
| | - Daniel Kazenmaier
- Max Planck Institute for Dynamics of Complex Technical Systems, Bioprocess Engineering, Magdeburg, Germany
- Faculty of Biotechnology, University of Applied Sciences Mannheim, Mannheim, Germany
| | - Natalie Tschorn
- Research Group Medical Biotechnology and Bioengineering, Faculty of Applied Natural Sciences, University of Applied Sciences Cologne, Campus Leverkusen, Cologne, Germany
- Institute of Technical Chemistry, Gottfried Wilhelm Leibniz University Hannover, Hanover, Germany
| | - Yvonne Genzel
- Max Planck Institute for Dynamics of Complex Technical Systems, Bioprocess Engineering, Magdeburg, Germany
| | - Jörn Stitz
- Research Group Medical Biotechnology and Bioengineering, Faculty of Applied Natural Sciences, University of Applied Sciences Cologne, Campus Leverkusen, Cologne, Germany
- *Correspondence: Jörn Stitz,
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Šimonová A, Romanská V, Benoni B, Škubník K, Šmerdová L, Prochazkova M, Spustová K, Moravčík O, Gahurova L, Pačes J, Plevka P, Cahova H. Honeybee iflaviruses pack specific tRNA fragments from host cells in their virions. Chembiochem 2022; 23:e202200281. [PMID: 35771148 PMCID: PMC9544947 DOI: 10.1002/cbic.202200281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 06/30/2022] [Indexed: 11/15/2022]
Abstract
The Picornavirales include viruses that infect vertebrates, insects, and plants. It was believed that they pack only their genomic mRNA in the particles; thus, we envisaged these viruses as excellent model systems for studies of mRNA modifications. We used LC–MS to analyze digested RNA isolated from particles of the sacbrood and deformed wing iflaviruses as well as of the echovirus 18 and rhinovirus 2 picornaviruses. Whereas in the picornavirus RNAs we detected only N6‐methyladenosine and 2’‐O‐methylated nucleosides, the iflavirus RNAs contained a wide range of methylated nucleosides, such as 1‐methyladenosine (m1A) and 5‐methylcytidine (m5C). Mapping of m1A and m5C through RNA sequencing of the SBV and DWV RNAs revealed the presence of tRNA molecules. Both modifications were detected only in tRNA. Further analysis revealed that tRNAs are present in form of 3’ and 5’ fragments and they are packed selectively. Moreover, these tRNAs are typically packed by other viruses.
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Affiliation(s)
- Anna Šimonová
- Charles University: Univerzita Karlova, First Faculty of Medicine, CZECH REPUBLIC
| | - Veronika Romanská
- Charles University: Univerzita Karlova, First Faculty of Medicine, CZECH REPUBLIC
| | - Barbora Benoni
- Charles University: Univerzita Karlova, First Faculty of Medicine, CZECH REPUBLIC
| | - Karel Škubník
- Masaryk University: Masarykova Univerzita, CEITEC, CZECH REPUBLIC
| | - Lenka Šmerdová
- Masaryk University: Masarykova Univerzita, CEITEC, CZECH REPUBLIC
| | | | - Kristina Spustová
- IOCB CAS: Ustav organicke chemie a biochemie Akademie ved Ceske republiky, Chemical Biology of Nucleic Acids, CZECH REPUBLIC
| | - Ondřej Moravčík
- Institute of Molecular Genetics Czech Academy of Sciences: Ustav molekularni genetiky Akademie Ved Ceske Republiky, Bioinformatic, CZECH REPUBLIC
| | - Lenka Gahurova
- University of South Bohemia Faculty of Science: Jihoceska Univerzita v Ceskych Budejovicich Prirodovedecka Fakulta, Departement of Molecular Biology, CZECH REPUBLIC
| | - Jan Pačes
- Institute of Molecular Genetics Czech Academy of Sciences: Ustav molekularni genetiky Akademie Ved Ceske Republiky, Bioinformatic, CZECH REPUBLIC
| | - Pavel Plevka
- Masaryk University: Masarykova Univerzita, CEITEC, CZECH REPUBLIC
| | - Hana Cahova
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nam. 2, 16610 Prague 6, Czech Republic, CZECH REPUBLIC
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Viral Membrane Fusion Proteins and RNA Sorting Mechanisms for the Molecular Delivery by Exosomes. Cells 2021; 10:cells10113043. [PMID: 34831268 PMCID: PMC8622164 DOI: 10.3390/cells10113043] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 10/29/2021] [Accepted: 11/02/2021] [Indexed: 11/21/2022] Open
Abstract
The advancement of precision medicine critically depends on the robustness and specificity of the carriers used for the targeted delivery of effector molecules in the human body. Numerous nanocarriers have been explored in vivo, to ensure the precise delivery of molecular cargos via tissue-specific targeting, including the endocrine part of the pancreas, thyroid, and adrenal glands. However, even after reaching the target organ, the cargo-carrying vehicle needs to enter the cell and then escape lysosomal destruction. Most artificial nanocarriers suffer from intrinsic limitations that prevent them from completing the specific delivery of the cargo. In this respect, extracellular vesicles (EVs) seem to be the natural tool for payload delivery due to their versatility and low toxicity. However, EV-mediated delivery is not selective and is usually short-ranged. By inserting the viral membrane fusion proteins into exosomes, it is possible to increase the efficiency of membrane recognition and also ease the process of membrane fusion. This review describes the molecular details of the viral-assisted interaction between the target cell and EVs. We also discuss the question of the usability of viral fusion proteins in developing extracellular vesicle-based nanocarriers with a higher efficacy of payload delivery. Finally, this review specifically highlights the role of Gag and RNA binding proteins in RNA sorting into EVs.
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5'-Cap sequestration is an essential determinant of HIV-1 genome packaging. Proc Natl Acad Sci U S A 2021; 118:2112475118. [PMID: 34493679 PMCID: PMC8449379 DOI: 10.1073/pnas.2112475118] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Accepted: 08/05/2021] [Indexed: 12/14/2022] Open
Abstract
HIV-1 selectively packages two copies of its 5'-capped RNA genome (gRNA) during virus assembly, a process mediated by the nucleocapsid (NC) domain of the viral Gag polyprotein and encapsidation signals located within the dimeric 5' leader of the viral RNA. Although residues within the leader that promote packaging have been identified, the determinants of authentic packaging fidelity and efficiency remain unknown. Here, we show that a previously characterized 159-nt region of the leader that possesses all elements required for RNA dimerization, high-affinity NC binding, and packaging in a noncompetitive RNA packaging assay (ΨCES) is unexpectedly poorly packaged when assayed in competition with the intact 5' leader. ΨCES lacks a 5'-tandem hairpin element that sequesters the 5' cap, suggesting that cap sequestration may be important for packaging. Consistent with this hypothesis, mutations within the intact leader that expose the cap without disrupting RNA structure or NC binding abrogated RNA packaging, and genetic addition of a 5' ribozyme to ΨCES to enable cotranscriptional shedding of the 5' cap promoted ΨCES-mediated RNA packaging to wild-type levels. Additional mutations that either block dimerization or eliminate subsets of NC binding sites substantially attenuated competitive packaging. Our studies indicate that packaging is achieved by a bipartite mechanism that requires both sequestration of the 5' cap and exposure of NC binding sites that reside fully within the ΨCES region of the dimeric leader. We speculate that cap sequestration prevents irreversible capture by the cellular RNA processing and translation machinery, a mechanism likely employed by other viruses that package 5'-capped RNA genomes.
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Loiseau V, Peccoud J, Bouzar C, Guillier S, Fan J, Alletti GG, Meignin C, Herniou EA, Federici BA, Wennmann JT, Jehle JA, Cordaux R, Gilbert C. Monitoring insect transposable elements in large double-stranded DNA viruses reveals host-to-virus and virus-to-virus transposition. Mol Biol Evol 2021; 38:3512-3530. [PMID: 34191026 PMCID: PMC8383894 DOI: 10.1093/molbev/msab198] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The mechanisms by which transposable elements (TEs) can be horizontally transferred between animals are unknown, but viruses are possible candidate vectors. Here, we surveyed the presence of host-derived TEs in viral genomes in 35 deep sequencing data sets produced from 11 host–virus systems, encompassing nine arthropod host species (five lepidopterans, two dipterans, and two crustaceans) and six different double-stranded (ds) DNA viruses (four baculoviruses and two iridoviruses). We found evidence of viral-borne TEs in 14 data sets, with frequencies of viral genomes carrying a TE ranging from 0.01% to 26.33% for baculoviruses and from 0.45% to 7.36% for iridoviruses. The analysis of viral populations separated by a single replication cycle revealed that viral-borne TEs originating from an initial host species can be retrieved after viral replication in another host species, sometimes at higher frequencies. Furthermore, we detected a strong increase in the number of integrations in a viral population for a TE absent from the hosts’ genomes, indicating that this TE has undergone intense transposition within the viral population. Finally, we provide evidence that many TEs found integrated in viral genomes (15/41) have been horizontally transferred in insects. Altogether, our results indicate that multiple large dsDNA viruses have the capacity to shuttle TEs in insects and they underline the potential of viruses to act as vectors of horizontal transfer of TEs. Furthermore, the finding that TEs can transpose between viral genomes of a viral species sets viruses as possible new niches in which TEs can persist and evolve.
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Affiliation(s)
- Vincent Loiseau
- Université Paris-Saclay, CNRS, IRD, UMR Évolution, Génomes, Comportement et Écologie, 91198 Gif-sur-Yvette, France
| | - Jean Peccoud
- Université de Poitiers, Laboratoire Ecologie et Biologie des Interactions, Equipe Ecologie Evolution Symbiose, 5 Rue Albert Turpain, TSA 51106, 86073, Poitiers Cedex 9, France
| | - Clémence Bouzar
- Université Paris-Saclay, CNRS, IRD, UMR Évolution, Génomes, Comportement et Écologie, 91198 Gif-sur-Yvette, France
| | - Sandra Guillier
- Université Paris-Saclay, CNRS, IRD, UMR Évolution, Génomes, Comportement et Écologie, 91198 Gif-sur-Yvette, France
| | - Jiangbin Fan
- Institute for Biological Control, Julius Kühn-Institut, Darmstadt, Germany
| | | | - Carine Meignin
- Modèles Insectes d'Immunité antivirale (M3i), Université de Strasbourg, IBMC CNRS-UPR9022, F-67000, France
| | - Elisabeth A Herniou
- Institut de Recherche sur la Biologie de l'Insecte, UMR7261 CNRS - Université de Tours, 37200 Tours, France
| | - Brian A Federici
- Department of Entomology, University of California, Riverside, CA 92521, USA
| | - Jörg T Wennmann
- Institute for Biological Control, Julius Kühn-Institut, Darmstadt, Germany
| | - Johannes A Jehle
- Institute for Biological Control, Julius Kühn-Institut, Darmstadt, Germany
| | - Richard Cordaux
- Université de Poitiers, Laboratoire Ecologie et Biologie des Interactions, Equipe Ecologie Evolution Symbiose, 5 Rue Albert Turpain, TSA 51106, 86073, Poitiers Cedex 9, France
| | - Clément Gilbert
- Université Paris-Saclay, CNRS, IRD, UMR Évolution, Génomes, Comportement et Écologie, 91198 Gif-sur-Yvette, France
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12
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Faoro C, Ataide SF. Noncanonical Functions and Cellular Dynamics of the Mammalian Signal Recognition Particle Components. Front Mol Biosci 2021; 8:679584. [PMID: 34113652 PMCID: PMC8185352 DOI: 10.3389/fmolb.2021.679584] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 04/29/2021] [Indexed: 12/24/2022] Open
Abstract
The signal recognition particle (SRP) is a ribonucleoprotein complex fundamental for co-translational delivery of proteins to their proper membrane localization and secretory pathways. Literature of the past two decades has suggested new roles for individual SRP components, 7SL RNA and proteins SRP9, SRP14, SRP19, SRP54, SRP68 and SRP72, outside the SRP cycle. These noncanonical functions interconnect SRP with a multitude of cellular and molecular pathways, including virus-host interactions, stress response, transcriptional regulation and modulation of apoptosis in autoimmune diseases. Uncovered novel properties of the SRP components present a new perspective for the mammalian SRP as a biological modulator of multiple cellular processes. As a consequence of these findings, SRP components have been correlated with a growing list of diseases, such as cancer progression, myopathies and bone marrow genetic diseases, suggesting a potential for development of SRP-target therapies of each individual component. For the first time, here we present the current knowledge on the SRP noncanonical functions and raise the need of a deeper understanding of the molecular interactions between SRP and accessory cellular components. We examine diseases associated with SRP components and discuss the development and feasibility of therapeutics targeting individual SRP noncanonical functions.
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Affiliation(s)
- Camilla Faoro
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia
| | - Sandro F Ataide
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia
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13
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Hantak MP, Einstein J, Kearns RB, Shepherd JD. Intercellular Communication in the Nervous System Goes Viral. Trends Neurosci 2021; 44:248-259. [PMID: 33485691 PMCID: PMC8041237 DOI: 10.1016/j.tins.2020.12.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 11/19/2020] [Accepted: 12/30/2020] [Indexed: 12/20/2022]
Abstract
Viruses and transposable elements are major drivers of evolution and make up over half the sequences in the human genome. In some cases, these elements are co-opted to perform biological functions for the host. Recent studies made the surprising observation that the neuronal gene Arc forms virus-like protein capsids that can transfer RNA between neurons to mediate a novel intercellular communication pathway. Phylogenetic analyses showed that mammalian Arc is derived from an ancient retrotransposon of the Ty3/gypsy family and contains homology to the retroviral Gag polyproteins. The Drosophila Arc homologs, which are independently derived from the same family of retrotransposons, also mediate cell-to-cell signaling of RNA at the neuromuscular junction; a striking example of convergent evolution. Here we propose an Arc 'life cycle', based on what is known about retroviral Gag, and discuss how elucidating these biological processes may lead to novel insights into brain plasticity and memory.
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Affiliation(s)
- Michael P Hantak
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT, USA
| | - Jenifer Einstein
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT, USA
| | - Rachel B Kearns
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT, USA
| | - Jason D Shepherd
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT, USA.
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14
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5-Methylcytosine RNA Modifications Promote Retrovirus Replication in an ALYREF Reader Protein-Dependent Manner. J Virol 2020; 94:JVI.00544-20. [PMID: 32321818 DOI: 10.1128/jvi.00544-20] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 04/12/2020] [Indexed: 12/20/2022] Open
Abstract
RNA modifications play diverse roles in regulating RNA function, and viruses co-opt these pathways for their own benefit. While recent studies have highlighted the importance of N 6-methyladenosine (m6A)-the most abundant mRNA modification-in regulating retrovirus replication, the identification and function of other RNA modifications in viral biology have been largely unexplored. Here, we characterized the RNA modifications present in a model retrovirus, murine leukemia virus (MLV), using mass spectrometry and sequencing. We found that 5-methylcytosine (m5C) is highly enriched in viral genomic RNA relative to uninfected cellular mRNAs, and we mapped at single-nucleotide resolution the m5C sites, which are located in multiple clusters throughout the MLV genome. Further, we showed that the m5C reader protein ALYREF plays an important role in regulating MLV replication. Together, our results provide a complete m5C profile in a virus and its function in a eukaryotic mRNA.IMPORTANCE Over 130 modifications have been identified in cellular RNAs, which play critical roles in many cellular processes, from modulating RNA stability to altering translation efficiency. One such modification, 5-methylcytosine, is relatively abundant in mammalian mRNAs, but its precise location and function are not well understood. In this study, we identified unexpectedly high levels of m5C in the murine leukemia virus RNA, precisely mapped its location, and showed that ALYREF, a reader protein that specifically recognizes m5C, regulates viral production. Together, our findings provide a high-resolution atlas of m5C in murine leukemia virus and reveal a functional role of m5C in viral replication.
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15
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Dhakal R, Tong C, Anderson S, Kashina AS, Cooperman B, Bau HH. Dynamics of intracellular stress-induced tRNA trafficking. Nucleic Acids Res 2019; 47:2002-2010. [PMID: 30496477 PMCID: PMC6393242 DOI: 10.1093/nar/gky1208] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 11/09/2018] [Accepted: 11/20/2018] [Indexed: 01/15/2023] Open
Abstract
Stress is known to induce retrograde tRNA translocation from the cytoplasm to the nucleus but translocation kinetics and tRNA-spatial distribution have not been characterized previously. We microinject fluorescently-labeled tRNA into living cells and use confocal microscopy to image tRNA spatial distribution in single cells at various levels of starvation and to determine translocation rate constants. Retrograde tRNA translocation occurs reversibly, within minutes after nutrition depletion of the extracellular medium. Such nutritional starvation leads to down-regulation of tRNA nuclear import and nearly complete curtailment of its nuclear export. Nuclear tRNA accumulation is suppressed in cells treated with the translation inhibitor puromycin, but is enhanced in cells treated with the microtubule inhibitor nocodazole. tRNA in the cytoplasm exhibits distinct spatial distribution inconsistent with diffusion, implying that such distribution is actively maintained. We propose that tRNA biological complexes and/or cytoplasmic electric fields are the likely regulators of cytoplasmic tRNA spatial distribution.
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Affiliation(s)
- Rabin Dhakal
- Department of Mechanical Engineering and Applied mechanics, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Chunyi Tong
- Department of Mechanical Engineering and Applied mechanics, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Sean Anderson
- Department of Mechanical Engineering and Applied mechanics, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Anna S Kashina
- Department of Biomedical Sciences, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Barry Cooperman
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19014, USA
| | - Haim H Bau
- Department of Mechanical Engineering and Applied mechanics, University of Pennsylvania, Philadelphia, PA 19104, USA
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16
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Ressel S, Rosca A, Gordon K, Buck AH. Extracellular RNA in viral-host interactions: Thinking outside the cell. WILEY INTERDISCIPLINARY REVIEWS. RNA 2019; 10:e1535. [PMID: 30963709 PMCID: PMC6617787 DOI: 10.1002/wrna.1535] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2019] [Revised: 03/13/2019] [Accepted: 03/14/2019] [Indexed: 12/15/2022]
Abstract
Small RNAs and their associated RNA interference (RNAi) pathways underpin diverse mechanisms of gene regulation and genome defense across all three kingdoms of life and are integral to virus-host interactions. In plants, fungi and many animals, an ancestral RNAi pathway exists as a host defense mechanism whereby viral double-stranded RNA is processed to small RNAs that enable recognition and degradation of the virus. While this antiviral RNAi pathway is not generally thought to be present in mammals, other RNAi mechanisms can influence infection through both viral- and host-derived small RNAs. Furthermore, a burgeoning body of data suggests that small RNAs in mammals can function in a non-cell autonomous manner to play various roles in cell-to-cell communication and disease through their transport in extracellular vesicles. While vesicular small RNAs have not been proposed as an antiviral defense pathway per se, there is increasing evidence that the export of host- or viral-derived RNAs from infected cells can influence various aspects of the infection process. This review discusses the current knowledge of extracellular RNA functions in viral infection and the technical challenges surrounding this field of research. This article is categorized under: Regulatory RNAs/RNAi/Riboswitches > Regulatory RNAs RNA in Disease and Development > RNA in Disease Regulatory RNAs/RNAi/Riboswitches > RNAi: Mechanisms of Action.
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Affiliation(s)
- Sarah Ressel
- Institute of Immunology and Infection Research, School of Biological SciencesUniversity of EdinburghEdinburghUK
| | - Adelina Rosca
- Department of VirologyCarol Davila University of Medicine and PharmacyBucharestRomania
| | - Katrina Gordon
- Institute of Immunology and Infection Research, School of Biological SciencesUniversity of EdinburghEdinburghUK
| | - Amy H. Buck
- Institute of Immunology and Infection Research, School of Biological SciencesUniversity of EdinburghEdinburghUK
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17
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LC/MS analysis and deep sequencing reveal the accurate RNA composition in the HIV-1 virion. Sci Rep 2019; 9:8697. [PMID: 31213632 PMCID: PMC6581912 DOI: 10.1038/s41598-019-45079-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 05/30/2019] [Indexed: 01/23/2023] Open
Abstract
The mechanism of action of various viruses has been the primary focus of many studies. Yet, the data on RNA modifications in any type of virus are scarce. Methods for the sensitive analysis of RNA modifications have been developed only recently and they have not been applied to viruses. In particular, the RNA composition of HIV-1 virions has never been determined with sufficiently exact methods. Here, we reveal that the RNA of HIV-1 virions contains surprisingly high amount of the 1-methyladenosine. We are the first to use a liquid chromatography-mass spectrometry analysis (LC/MS) of virion RNA, which we combined with m1A profiling and deep sequencing. We found that m1A was present in the tRNA, but not in the genomic HIV-1 RNA and the abundant 7SL RNA. We were able to calculate that an HIV-1 virion contains per 2 copies of genomic RNA and 14 copies of 7SL RNA also 770 copies of tRNA, which is approximately 10 times more than thus far expected. These new insights into the composition of the HIV-1 virion can help in future studies to identify the role of nonprimer tRNAs in retroviruses. Moreover, we present a promising new tool for studying the compositions of virions.
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18
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Driedonks TAP, Nolte-'t Hoen ENM. Circulating Y-RNAs in Extracellular Vesicles and Ribonucleoprotein Complexes; Implications for the Immune System. Front Immunol 2019; 9:3164. [PMID: 30697216 PMCID: PMC6340977 DOI: 10.3389/fimmu.2018.03164] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 12/21/2018] [Indexed: 12/25/2022] Open
Abstract
The exchange of extracellular vesicles (EV) between immune cells plays a role in various immune regulatory processes. EV are nano-sized lipid bilayer-enclosed structures that contain a multitude of proteins and small non-coding RNA molecules. Of the various RNA classes present in EV, miRNAs have been most intensively studied because of their known gene-regulatory functions. These miRNAs constitute only a minor part of all EV-enclosed RNA, whereas other 20–200 nt sized non-coding RNAs were shown to be abundantly present in EV. Several of these mid-sized RNAs perform basic functions in cells, but their function in EV remains elusive. One prominent class of mid-sized extracellular RNAs associated with EV are the Y-RNAs. This family of highly conserved non-coding RNAs was initially discovered as RNA component of circulating ribonucleoprotein autoantigens in serum from Systemic Lupus Erythematosus and Sjögren's Syndrome patients. Y-RNA has been implicated in cellular processes such as DNA replication and RNA quality control. In recent years, Y-RNA has been abundantly detected in EV from multiple different cell lines and biofluids, and also in murine and human retroviruses. Accumulating evidence suggests that EV-associated Y-RNA may be involved in a range of immune-related processes, including inflammation, immune suppression, and establishment of the tumor microenvironment. Moreover, changes in plasma levels of extracellular Y-RNA have been associated with various diseases. Recent studies have aimed to address the mechanisms underlying their release and function. We for example showed that the levels of EV-associated Y-RNA released by immune cells can be regulated by Toll-like receptor (TLR) signaling. Combined, these data have triggered increased interest in extracellular Y-RNAs. In this review, we provide an overview of studies reporting the occurrence of extracellular Y-RNAs, as well as signaling properties and immune-related functions attributed to these RNAs. We list RNA-binding proteins currently known to interact with Y-RNAs and evaluate their occurrence in EV. In parallel, we discuss technical challenges in assessing whether extracellular Y-RNAs are contained in ribonucleoprotein complexes or EV. By integrating the current knowledge on extracellular Y-RNA we further reflect on the biomarker potential of Y-RNA and their role in immune cell communication and immunopathology.
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Affiliation(s)
- Tom A P Driedonks
- Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Esther N M Nolte-'t Hoen
- Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
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19
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Renner TM, Bélanger K, Langlois MA. Selective Isolation of Retroviruses from Extracellular Vesicles by Intact Virion Immunoprecipitation. Bio Protoc 2018; 8:e3005. [PMID: 34395797 DOI: 10.21769/bioprotoc.3005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 08/16/2018] [Accepted: 08/29/2018] [Indexed: 01/08/2023] Open
Abstract
There exists a wide variety of techniques to isolate and purify viral particles from cell culture supernatants. However, these techniques vary greatly in ease of use, purity, yield and impact on viral structural integrity. Most importantly, it is becoming evident that secreted extracellular vesicles (EVs) co-purify with retroviruses using nearly all purification methods due to nearly indistinguishable biophysical characteristics such as size, buoyant density and nucleic acid content. Recently, our group has illustrated a means of isolating intact and highly enriched retroviral virions from EV-containing cell supernatants using an immunoprecipitation approach targeting the viral envelope glycoprotein of the Moloney Murine Leukemia Virus ( Renner et al., 2018 ). This technique, that we call intact virion immunoprecipitation (IVIP), enabled us to characterize the accessibility of epitopes on the surface of these retroviruses and assess the orientation of the virus-encoded integral membrane protein Glycogag (gPr80) in the viral envelope. Proper implementation of this protocol enables fast, simple and reproducible preparations of intact and highly purified retroviral particles devoid of detectable EV contaminants.
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Affiliation(s)
- Tyler Milston Renner
- Department of Biochemistry, Microbiology & Immunology, University of Ottawa, Ottawa, Canada
| | - Kasandra Bélanger
- Department of Biochemistry, Microbiology & Immunology, University of Ottawa, Ottawa, Canada
| | - Marc-André Langlois
- Department of Biochemistry, Microbiology & Immunology, University of Ottawa, Ottawa, Canada
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20
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Lu W, Tirumuru N, St Gelais C, Koneru PC, Liu C, Kvaratskhelia M, He C, Wu L. N6-Methyladenosine-binding proteins suppress HIV-1 infectivity and viral production. J Biol Chem 2018; 293:12992-13005. [PMID: 29976753 PMCID: PMC6109920 DOI: 10.1074/jbc.ra118.004215] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Revised: 06/27/2018] [Indexed: 11/06/2022] Open
Abstract
The internal N6-methyladenosine (m6A) modification of cellular mRNA regulates post-transcriptional gene expression. The YTH domain family proteins (YTHDF1-3 or Y1-3) bind to m6A-modified cellular mRNAs and modulate their metabolism and processing, thereby affecting cellular protein translation. We previously reported that HIV-1 RNA contains the m6A modification and that Y1-3 proteins inhibit HIV-1 infection by decreasing HIV-1 reverse transcription activity. Here, we investigated the mechanisms of Y1-3-mediated inhibition of HIV-1 infection in target cells and the effect of Y1-3 on viral production levels in virus-producing cells. We found that Y1-3 protein overexpression in HIV-1 target cells decreases viral genomic RNA (gRNA) levels and inhibits both early and late reverse transcription. Purified recombinant Y1-3 proteins preferentially bound to the m6A-modified 5' leader sequence of gRNA compared with its unmodified RNA counterpart, consistent with the strong binding of Y1-3 proteins to HIV-1 gRNA in infected cells. HIV-1 mutants with two altered m6A modification sites in the 5' leader sequence of gRNA exhibited significantly lower infectivity than WT, replication-competent HIV-1, confirming that these sites alter viral infection. HIV-1 produced from cells in which endogenous Y1, Y3, or Y1-3 proteins were knocked down singly or together had increased viral infectivity compared with HIV-1 produced in control cells. Interestingly, we found that Y1-3 proteins and HIV-1 Gag protein formed a complex with RNA in HIV-1-producing cells. Overall, these results indicate that Y1-3 proteins inhibit HIV-1 infection and provide new insights into the mechanisms by which the m6A modification of HIV-1 RNA affects viral replication.
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Affiliation(s)
- Wuxun Lu
- From the Center for Retrovirus Research, Department of Veterinary Biosciences, Ohio State University, Columbus, Ohio 43210
| | - Nagaraja Tirumuru
- From the Center for Retrovirus Research, Department of Veterinary Biosciences, Ohio State University, Columbus, Ohio 43210
| | - Corine St Gelais
- From the Center for Retrovirus Research, Department of Veterinary Biosciences, Ohio State University, Columbus, Ohio 43210
| | - Pratibha C Koneru
- the Division of Infectious Diseases, University of Colorado School of Medicine, Aurora, Colorado 80045, and
| | - Chang Liu
- the Departments of Chemistry and of Biochemistry and Molecular Biology, Institute for Biophysical Dynamics, and
- Howard Hughes Medical Institute, University of Chicago, Chicago, Illinois 60637
| | - Mamuka Kvaratskhelia
- the Division of Infectious Diseases, University of Colorado School of Medicine, Aurora, Colorado 80045, and
| | - Chuan He
- the Departments of Chemistry and of Biochemistry and Molecular Biology, Institute for Biophysical Dynamics, and
- Howard Hughes Medical Institute, University of Chicago, Chicago, Illinois 60637
| | - Li Wu
- From the Center for Retrovirus Research, Department of Veterinary Biosciences, Ohio State University, Columbus, Ohio 43210,
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21
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Mutations in the Basic Region of the Mason-Pfizer Monkey Virus Nucleocapsid Protein Affect Reverse Transcription, Genomic RNA Packaging, and the Virus Assembly Site. J Virol 2018; 92:JVI.00106-18. [PMID: 29491167 DOI: 10.1128/jvi.00106-18] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Accepted: 02/20/2018] [Indexed: 12/19/2022] Open
Abstract
In addition to specific RNA-binding zinc finger domains, the retroviral Gag polyprotein contains clusters of basic amino acid residues that are thought to support Gag-viral genomic RNA (gRNA) interactions. One of these clusters is the basic K16NK18EK20 region, located upstream of the first zinc finger of the Mason-Pfizer monkey virus (M-PMV) nucleocapsid (NC) protein. To investigate the role of this basic region in the M-PMV life cycle, we used a combination of in vivo and in vitro methods to study a series of mutants in which the overall charge of this region was more positive (RNRER), more negative (AEAEA), or neutral (AAAAA). The mutations markedly affected gRNA incorporation and the onset of reverse transcription. The introduction of a more negative charge (AEAEA) significantly reduced the incorporation of M-PMV gRNA into nascent particles. Moreover, the assembly of immature particles of the AEAEA Gag mutant was relocated from the perinuclear region to the plasma membrane. In contrast, an enhancement of the basicity of this region of M-PMV NC (RNRER) caused a substantially more efficient incorporation of gRNA, subsequently resulting in an increase in M-PMV RNRER infectivity. Nevertheless, despite the larger amount of gRNA packaged by the RNRER mutant, the onset of reverse transcription was delayed in comparison to that of the wild type. Our data clearly show the requirement for certain positively charged amino acid residues upstream of the first zinc finger for proper gRNA incorporation, assembly of immature particles, and proceeding of reverse transcription.IMPORTANCE We identified a short sequence within the Gag polyprotein that, together with the zinc finger domains and the previously identified RKK motif, contributes to the packaging of genomic RNA (gRNA) of Mason-Pfizer monkey virus (M-PMV). Importantly, in addition to gRNA incorporation, this basic region (KNKEK) at the N terminus of the nucleocapsid protein is crucial for the onset of reverse transcription. Mutations that change the positive charge of the region to a negative one significantly reduced specific gRNA packaging. The assembly of immature particles of this mutant was reoriented from the perinuclear region to the plasma membrane. On the contrary, an enhancement of the basic character of this region increased both the efficiency of gRNA packaging and the infectivity of the virus. However, the onset of reverse transcription was delayed even in this mutant. In summary, the basic region in M-PMV Gag plays a key role in the packaging of genomic RNA and, consequently, in assembly and reverse transcription.
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22
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Steele EJ, Al-Mufti S, Augustyn KA, Chandrajith R, Coghlan JP, Coulson SG, Ghosh S, Gillman M, Gorczynski RM, Klyce B, Louis G, Mahanama K, Oliver KR, Padron J, Qu J, Schuster JA, Smith WE, Snyder DP, Steele JA, Stewart BJ, Temple R, Tokoro G, Tout CA, Unzicker A, Wainwright M, Wallis J, Wallis DH, Wallis MK, Wetherall J, Wickramasinghe DT, Wickramasinghe JT, Wickramasinghe NC, Liu Y. Cause of Cambrian Explosion - Terrestrial or Cosmic? PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2018; 136:3-23. [PMID: 29544820 DOI: 10.1016/j.pbiomolbio.2018.03.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
We review the salient evidence consistent with or predicted by the Hoyle-Wickramasinghe (H-W) thesis of Cometary (Cosmic) Biology. Much of this physical and biological evidence is multifactorial. One particular focus are the recent studies which date the emergence of the complex retroviruses of vertebrate lines at or just before the Cambrian Explosion of ∼500 Ma. Such viruses are known to be plausibly associated with major evolutionary genomic processes. We believe this coincidence is not fortuitous but is consistent with a key prediction of H-W theory whereby major extinction-diversification evolutionary boundaries coincide with virus-bearing cometary-bolide bombardment events. A second focus is the remarkable evolution of intelligent complexity (Cephalopods) culminating in the emergence of the Octopus. A third focus concerns the micro-organism fossil evidence contained within meteorites as well as the detection in the upper atmosphere of apparent incoming life-bearing particles from space. In our view the totality of the multifactorial data and critical analyses assembled by Fred Hoyle, Chandra Wickramasinghe and their many colleagues since the 1960s leads to a very plausible conclusion - life may have been seeded here on Earth by life-bearing comets as soon as conditions on Earth allowed it to flourish (about or just before 4.1 Billion years ago); and living organisms such as space-resistant and space-hardy bacteria, viruses, more complex eukaryotic cells, fertilised ova and seeds have been continuously delivered ever since to Earth so being one important driver of further terrestrial evolution which has resulted in considerable genetic diversity and which has led to the emergence of mankind.
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Affiliation(s)
- Edward J Steele
- CY O'Connor ERADE Village Foundation, Piara Waters, WA, Australia; Centre for Astrobiology, University of Ruhuna, Matara, Sri Lanka.
| | - Shirwan Al-Mufti
- Buckingham Centre for Astrobiology, University of Buckingham, UK
| | - Kenneth A Augustyn
- Center for the Physics of Living Organisms, Department of Physics, Michigan Technological University, Michigan, United States
| | | | - John P Coghlan
- University of Melbourne, Office of the Dean, Faculty Medicine, Dentistry and Health Sciences, 3rd Level, Alan Gilbert Building, Australia
| | - S G Coulson
- Buckingham Centre for Astrobiology, University of Buckingham, UK
| | - Sudipto Ghosh
- Metallurgical & Materials Engineering IIT, Kanpur, India
| | - Mark Gillman
- South African Brain Research Institute, 6 Campbell Street, Waverly, Johannesburg, South Africa
| | - Reginald M Gorczynski
- University Toronto Health Network, Toronto General Hospital, University of Toronto, Canada
| | - Brig Klyce
- Buckingham Centre for Astrobiology, University of Buckingham, UK
| | - Godfrey Louis
- Department of Physics, Cochin University of Science and Technology Cochin, India
| | | | - Keith R Oliver
- School of Veterinary and Life Sciences Murdoch University, Perth, WA, Australia
| | - Julio Padron
- Studio Eutropi, Clinical Pathology and Nutrition, Via Pompei 46, Ardea, 00040, Rome, Italy
| | - Jiangwen Qu
- Department of Infectious Disease Control, Tianjin Center for Disease Control and Prevention, China
| | - John A Schuster
- School of History and Philosophy of Science, Faculty of Science, University of Sydney, Sydney, Australia
| | - W E Smith
- Institute for the Study of Panspermia and Astrobiology, Gifu, Japan
| | - Duane P Snyder
- Buckingham Centre for Astrobiology, University of Buckingham, UK
| | - Julian A Steele
- Centre for Surface Chemistry and Catalysis, KU Leuven, Celestijnenlaan 200F, 3001, Leuven, Belgium
| | - Brent J Stewart
- CY O'Connor ERADE Village Foundation, Piara Waters, WA, Australia
| | - Robert Temple
- The History of Chinese Culture Foundation, Conway Hall, London, UK
| | - Gensuke Tokoro
- Institute for the Study of Panspermia and Astrobiology, Gifu, Japan
| | - Christopher A Tout
- Institute of Astronomy, The Observatories, Madingley Road, Cambridge, CB3 0HA, UK
| | | | - Milton Wainwright
- Buckingham Centre for Astrobiology, University of Buckingham, UK; Centre for Astrobiology, University of Ruhuna, Matara, Sri Lanka
| | - Jamie Wallis
- Buckingham Centre for Astrobiology, University of Buckingham, UK
| | - Daryl H Wallis
- Buckingham Centre for Astrobiology, University of Buckingham, UK
| | - Max K Wallis
- Buckingham Centre for Astrobiology, University of Buckingham, UK
| | - John Wetherall
- School of Biomedical Sciences, Perth, Curtin University, WA, Australia
| | - D T Wickramasinghe
- College of Physical and Mathematical Sciences, Australian National University, Canberra, Australia
| | | | - N Chandra Wickramasinghe
- Buckingham Centre for Astrobiology, University of Buckingham, UK; Centre for Astrobiology, University of Ruhuna, Matara, Sri Lanka; Institute for the Study of Panspermia and Astrobiology, Gifu, Japan
| | - Yongsheng Liu
- Henan Collaborative Innovation Center of Modern Biological Breeding, Henan Institute of Science and Technology, Xinxiang, 453003, China; Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
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23
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Noncoding RNAs in Retrovirus Replication. RETROVIRUS-CELL INTERACTIONS 2018. [PMCID: PMC7173536 DOI: 10.1016/b978-0-12-811185-7.00012-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Although a limited percentage of the genome produces proteins, approximately 90% is transcribed, indicating important roles for noncoding RNA (ncRNA). It is now known that these ncRNAs have a multitude of cellular functions ranging from the regulation of gene expression to roles as structural elements in ribonucleoprotein complexes. ncRNA is also represented at nearly every step of viral life cycles. This chapter will focus on ncRNAs of both host and viral origin and their roles in retroviral life cycles. Cellular ncRNA represents a significant portion of material packaged into retroviral virions and includes transfer RNAs, 7SL RNA, U RNA, and vault RNA. Initially thought to be random packaging events, these host RNAs are now proposed to contribute to viral assembly and infectivity. Within the cell, long ncRNA and endogenous retroviruses have been found to regulate aspects of the retroviral life cycle in diverse ways. Additionally, the HIV-1 transactivating response element RNA is thought to impact viral infection beyond the well-characterized role as a transcription activator. RNA interference, thought to be an early version of the innate immune response to viral infection, can still be observed in plants and invertebrates today. The ability of retroviral infection to manipulate the host RNAi pathway is described here. Finally, RNA-based therapies, including gene editing approaches, are being explored as antiretroviral treatments and are discussed.
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Cross- and Co-Packaging of Retroviral RNAs and Their Consequences. Viruses 2016; 8:v8100276. [PMID: 27727192 PMCID: PMC5086612 DOI: 10.3390/v8100276] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 10/03/2016] [Accepted: 10/03/2016] [Indexed: 12/23/2022] Open
Abstract
Retroviruses belong to the family Retroviridae and are ribonucleoprotein (RNP) particles that contain a dimeric RNA genome. Retroviral particle assembly is a complex process, and how the virus is able to recognize and specifically capture the genomic RNA (gRNA) among millions of other cellular and spliced retroviral RNAs has been the subject of extensive investigation over the last two decades. The specificity towards RNA packaging requires higher order interactions of the retroviral gRNA with the structural Gag proteins. Moreover, several retroviruses have been shown to have the ability to cross-/co-package gRNA from other retroviruses, despite little sequence homology. This review will compare the determinants of gRNA encapsidation among different retroviruses, followed by an examination of our current understanding of the interaction between diverse viral genomes and heterologous proteins, leading to their cross-/co-packaging. Retroviruses are well-known serious animal and human pathogens, and such a cross-/co-packaging phenomenon could result in the generation of novel viral variants with unknown pathogenic potential. At the same time, however, an enhanced understanding of the molecular mechanisms involved in these specific interactions makes retroviruses an attractive target for anti-viral drugs, vaccines, and vectors for human gene therapy.
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25
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Orchestrating the Selection and Packaging of Genomic RNA by Retroviruses: An Ensemble of Viral and Host Factors. Viruses 2016; 8:v8090257. [PMID: 27657110 PMCID: PMC5035971 DOI: 10.3390/v8090257] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2016] [Revised: 09/09/2016] [Accepted: 09/13/2016] [Indexed: 12/31/2022] Open
Abstract
Infectious retrovirus particles contain two copies of unspliced viral RNA that serve as the viral genome. Unspliced retroviral RNA is transcribed in the nucleus by the host RNA polymerase II and has three potential fates: (1) it can be spliced into subgenomic messenger RNAs (mRNAs) for the translation of viral proteins; or it can remain unspliced to serve as either (2) the mRNA for the translation of Gag and Gag-Pol; or (3) the genomic RNA (gRNA) that is packaged into virions. The Gag structural protein recognizes and binds the unspliced viral RNA to select it as a genome, which is selected in preference to spliced viral RNAs and cellular RNAs. In this review, we summarize the current state of understanding about how retroviral packaging is orchestrated within the cell and explore potential new mechanisms based on recent discoveries in the field. We discuss the cis-acting elements in the unspliced viral RNA and the properties of the Gag protein that are required for their interaction. In addition, we discuss the role of host factors in influencing the fate of the newly transcribed viral RNA, current models for how retroviruses distinguish unspliced viral mRNA from viral genomic RNA, and the possible subcellular sites of genomic RNA dimerization and selection by Gag. Although this review centers primarily on the wealth of data available for the alpharetrovirus Rous sarcoma virus, in which a discrete RNA packaging sequence has been identified, we have also summarized the cis- and trans-acting factors as well as the mechanisms governing gRNA packaging of other retroviruses for comparison.
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26
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Comas-Garcia M, Davis SR, Rein A. On the Selective Packaging of Genomic RNA by HIV-1. Viruses 2016; 8:v8090246. [PMID: 27626441 PMCID: PMC5035960 DOI: 10.3390/v8090246] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Revised: 08/16/2016] [Accepted: 08/30/2016] [Indexed: 12/12/2022] Open
Abstract
Like other retroviruses, human immunodeficiency virus type 1 (HIV-1) selectively packages genomic RNA (gRNA) during virus assembly. However, in the absence of the gRNA, cellular messenger RNAs (mRNAs) are packaged. While the gRNA is selected because of its cis-acting packaging signal, the mechanism of this selection is not understood. The affinity of Gag (the viral structural protein) for cellular RNAs at physiological ionic strength is not much higher than that for the gRNA. However, binding to the gRNA is more salt-resistant, implying that it has a higher non-electrostatic component. We have previously studied the spacer 1 (SP1) region of Gag and showed that it can undergo a concentration-dependent conformational transition. We proposed that this transition represents the first step in assembly, i.e., the conversion of Gag to an assembly-ready state. To explain selective packaging of gRNA, we suggest here that binding of Gag to gRNA, with its high non-electrostatic component, triggers this conversion more readily than binding to other RNAs; thus we predict that a Gag-gRNA complex will nucleate particle assembly more efficiently than other Gag-RNA complexes. New data shows that among cellular mRNAs, those with long 3'-untranslated regions (UTR) are selectively packaged. It seems plausible that the 3'-UTR, a stretch of RNA not occupied by ribosomes, offers a favorable binding site for Gag.
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Affiliation(s)
- Mauricio Comas-Garcia
- HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702, USA.
| | - Sean R Davis
- Genetics Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA.
| | - Alan Rein
- HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702, USA.
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27
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The Life-Cycle of the HIV-1 Gag-RNA Complex. Viruses 2016; 8:v8090248. [PMID: 27626439 PMCID: PMC5035962 DOI: 10.3390/v8090248] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 08/30/2016] [Accepted: 09/02/2016] [Indexed: 12/16/2022] Open
Abstract
Human immunodeficiency virus type 1 (HIV-1) replication is a highly regulated process requiring the recruitment of viral and cellular components to the plasma membrane for assembly into infectious particles. This review highlights the recent process of understanding the selection of the genomic RNA (gRNA) by the viral Pr55Gag precursor polyprotein, and the processes leading to its incorporation into viral particles.
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28
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Telesnitsky A, Wolin SL. The Host RNAs in Retroviral Particles. Viruses 2016; 8:v8080235. [PMID: 27548206 PMCID: PMC4997597 DOI: 10.3390/v8080235] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 08/15/2016] [Accepted: 08/16/2016] [Indexed: 12/15/2022] Open
Abstract
As they assemble, retroviruses encapsidate both their genomic RNAs and several types of host RNA. Whereas limited amounts of messenger RNA (mRNA) are detectable within virion populations, the predominant classes of encapsidated host RNAs do not encode proteins, but instead include endogenous retroelements and several classes of non-coding RNA (ncRNA), some of which are packaged in significant molar excess to the viral genome. Surprisingly, although the most abundant host RNAs in retroviruses are also abundant in cells, unusual forms of these RNAs are packaged preferentially, suggesting that these RNAs are recruited early in their biogenesis: before associating with their cognate protein partners, and/or from transient or rare RNA populations. These RNAs' packaging determinants differ from the viral genome's, and several of the abundantly packaged host ncRNAs serve cells as the scaffolds of ribonucleoprotein particles. Because virion assembly is equally efficient whether or not genomic RNA is available, yet RNA appears critical to the structural integrity of retroviral particles, it seems possible that the selectively encapsidated host ncRNAs might play roles in assembly. Indeed, some host ncRNAs appear to act during replication, as some transfer RNA (tRNA) species may contribute to nuclear import of human immunodeficiency virus 1 (HIV-1) reverse transcription complexes, and other tRNA interactions with the viral Gag protein aid correct trafficking to plasma membrane assembly sites. However, despite high conservation of packaging for certain host RNAs, replication roles for most of these selectively encapsidated RNAs-if any-have remained elusive.
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Affiliation(s)
- Alice Telesnitsky
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, MI 48109, USA.
| | - Sandra L Wolin
- Department of Cell Biology, Yale School of Medicine, New Haven, CT 06536, USA.
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29
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Eckwahl MJ, Arnion H, Kharytonchyk S, Zang T, Bieniasz PD, Telesnitsky A, Wolin SL. Analysis of the human immunodeficiency virus-1 RNA packageome. RNA (NEW YORK, N.Y.) 2016; 22:1228-38. [PMID: 27247436 PMCID: PMC4931115 DOI: 10.1261/rna.057299.116] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2016] [Accepted: 05/15/2016] [Indexed: 05/16/2023]
Abstract
All retroviruses package cellular RNAs into virions. Studies of murine leukemia virus (MLV) revealed that the major host cell RNAs encapsidated by this simple retrovirus were LTR retrotransposons and noncoding RNAs (ncRNAs). Several classes of ncRNAs appeared to be packaged by MLV shortly after synthesis, as precursors to tRNAs, small nuclear RNAs, and small nucleolar RNAs were all enriched in virions. To determine the extent to which the human immunodeficiency virus (HIV-1) packages similar RNAs, we used high-throughput sequencing to characterize the RNAs within infectious HIV-1 virions produced in CEM-SS T lymphoblastoid cells. We report that the most abundant cellular RNAs in HIV-1 virions are 7SL RNA and transcripts from numerous divergent and truncated members of the long interspersed element (LINE) and short interspersed element (SINE) families of retrotransposons. We also detected precursors to several tRNAs and small nuclear RNAs as well as transcripts derived from the ribosomal DNA (rDNA) intergenic spacers. We show that packaging of a pre-tRNA requires the nuclear export receptor Exportin 5, indicating that HIV-1 recruits at least some newly made ncRNAs in the cytoplasm. Together, our work identifies the set of RNAs packaged by HIV-1 and reveals that early steps in HIV-1 assembly intersect with host cell ncRNA biogenesis pathways.
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Affiliation(s)
- Matthew J Eckwahl
- Department of Cell Biology, Yale School of Medicine, New Haven, Connecticut 06536, USA
| | - Helene Arnion
- Department of Cell Biology, Yale School of Medicine, New Haven, Connecticut 06536, USA
| | - Siarhei Kharytonchyk
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Trinity Zang
- Aaron Diamond AIDS Research Center, The Rockefeller University, New York, New York 10016, USA Laboratory of Retrovirology, The Rockefeller University, New York, New York 10016, USA Howard Hughes Medical Institute, The Rockefeller University, New York, New York 10016, USA
| | - Paul D Bieniasz
- Aaron Diamond AIDS Research Center, The Rockefeller University, New York, New York 10016, USA Laboratory of Retrovirology, The Rockefeller University, New York, New York 10016, USA Howard Hughes Medical Institute, The Rockefeller University, New York, New York 10016, USA
| | - Alice Telesnitsky
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Sandra L Wolin
- Department of Cell Biology, Yale School of Medicine, New Haven, Connecticut 06536, USA Department of Molecular Biophysics and Biochemistry, Yale School of Medicine, New Haven, Connecticut 06536, USA Yale Cancer Center, Yale School of Medicine, New Haven, Connecticut 06520, USA
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