1
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Aruda J, Grote SL, Rouskin S. Untangling the pseudoknots of SARS-CoV-2: Insights into structural heterogeneity and plasticity. Curr Opin Struct Biol 2024; 88:102912. [PMID: 39168046 DOI: 10.1016/j.sbi.2024.102912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2024] [Revised: 07/26/2024] [Accepted: 07/29/2024] [Indexed: 08/23/2024]
Abstract
Since the onset of the COVID-19 pandemic, one productive area of research has focused on the intricate two- and three-dimensional structures taken on by SARS-CoV-2's RNA genome. These structures control essential viral processes, making them tempting targets for therapeutic intervention. This review focuses on two such structured regions, the frameshift stimulation element (FSE), which controls the translation of viral protein, and the 3' untranslated region (3' UTR), which is thought to regulate genome replication. For the FSE, we discuss its canonical pseudoknot's threaded and unthreaded topologies, as well as the diversity of competing two-dimensional structures formed by local and long-distance base pairing. For the 3' UTR, we review the evidence both for and against the formation of its replication-enabling pseudoknot.
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Affiliation(s)
- Justin Aruda
- Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA; Harvard Program in Biological and Biomedical Sciences, Division of Medical Sciences, Harvard Medical School, Boston, MA 02115, USA
| | - Scott L Grote
- Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA
| | - Silvi Rouskin
- Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA.
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2
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Hernández-Marín M, Cantero-Camacho Á, Mena I, López-Núñez S, García-Sastre A, Gallego J. Sarbecovirus programmed ribosome frameshift RNA element folding studied by NMR spectroscopy and comparative analyses. Nucleic Acids Res 2024:gkae704. [PMID: 39149904 DOI: 10.1093/nar/gkae704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2024] [Revised: 07/24/2024] [Accepted: 08/05/2024] [Indexed: 08/17/2024] Open
Abstract
The programmed ribosomal frameshift (PRF) region is found in the RNA genome of all coronaviruses and shifts the ribosome reading frame through formation of a three-stem pseudoknot structure, allowing the translation of essential viral proteins. Using NMR spectroscopy, comparative sequence analyses and functional assays we show that, in the absence of the ribosome, a 123-nucleotide sequence encompassing the PRF element of SARS-CoV-2 adopts a well-defined two-stem loop structure that is conserved in all SARS-like coronaviruses. In this conformation, the attenuator hairpin and slippery site nucleotides are exposed in the first stem-loop and two pseudoknot stems are present in the second stem-loop, separated by an 8-nucleotide bulge. Formation of the third pseudoknot stem depends on pairing between bulge nucleotides and base-paired nucleotides of the upstream stem-loop, as shown by a PRF construct where residues of the upstream stem were removed, which formed the pseudoknot structure and had increased frameshifting activity in a dual-luciferase assay. The base-pair switch driving PRF pseudoknot folding was found to be conserved in several human non-SARS coronaviruses. The collective results suggest that the frameshifting pseudoknot structure of these viruses only forms transiently in the presence of the translating ribosome. These findings clarify the frameshifting mechanism in coronaviruses and can have a beneficial impact on antiviral drug discovery.
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Affiliation(s)
- María Hernández-Marín
- Centro de Investigación Traslacional San Alberto Magno, Universidad Católica de Valencia, 46001 Valencia, Spain
- Escuela de Doctorado, Universidad Católica de Valencia, 46001 Valencia, Spain
| | - Ángel Cantero-Camacho
- Centro de Investigación Traslacional San Alberto Magno, Universidad Católica de Valencia, 46001 Valencia, Spain
| | - Ignacio Mena
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, NY, USA
| | - Sergio López-Núñez
- Centro de Investigación Traslacional San Alberto Magno, Universidad Católica de Valencia, 46001 Valencia, Spain
- Escuela de Doctorado, Universidad Católica de Valencia, 46001 Valencia, Spain
| | - Adolfo García-Sastre
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, NY, USA
- Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, NY, USA
- Department of Medicine, Icahn School of Medicine at Mount Sinai, NY, USA
- Department of Pathology, Molecular and Cell-Based Medicine, Icahn School of Medicine at Mount Sinai, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, NY, USA
| | - José Gallego
- Centro de Investigación Traslacional San Alberto Magno, Universidad Católica de Valencia, 46001 Valencia, Spain
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3
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Mathez G, Brancale A, Cagno V. Novel Inhibitors of SARS-CoV-2 RNA Identified through Virtual Screening. J Chem Inf Model 2024; 64:6190-6196. [PMID: 39037082 PMCID: PMC11323243 DOI: 10.1021/acs.jcim.4c00758] [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: 05/01/2024] [Revised: 07/08/2024] [Accepted: 07/10/2024] [Indexed: 07/23/2024]
Abstract
We currently lack antivirals for most human viruses. In a quest for new molecules, focusing on viral RNA, instead of viral proteins, can represent a promising strategy. In this study, new inhibitors were identified starting from a published crystal structure of the tertiary SARS-CoV-2 RNA involved in the -1 programmed ribosomal frameshift. The pseudoknot structure was refined, and a virtual screening was performed using the repository of binders to the nucleic acid library, taking into consideration RNA flexibility. Hit compounds were validated against the wild-type virus and with a dual-luciferase assay measuring the frameshift efficiency. Several active molecules were identified. Our study reveals new inhibitors of SARS-CoV-2 but also highlights the feasibility of targeting RNA starting from virtual screening, a strategy that could be broadly applied to drug development.
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Affiliation(s)
- Gregory Mathez
- Institute
of Microbiology, University Hospital of
Lausanne, University of Lausanne, 1011 Lausanne, Switzerland
- Department
of Organic Chemistry, University of Chemistry
and Technology Prague, 16628 Prague 6, Czech Republic
| | - Andrea Brancale
- Department
of Organic Chemistry, University of Chemistry
and Technology Prague, 16628 Prague 6, Czech Republic
| | - Valeria Cagno
- Institute
of Microbiology, University Hospital of
Lausanne, University of Lausanne, 1011 Lausanne, Switzerland
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4
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Allan MF, Aruda J, Plung JS, Grote SL, des Taillades YJM, de Lajarte AA, Bathe M, Rouskin S. Discovery and Quantification of Long-Range RNA Base Pairs in Coronavirus Genomes with SEARCH-MaP and SEISMIC-RNA. RESEARCH SQUARE 2024:rs.3.rs-4814547. [PMID: 39149495 PMCID: PMC11326378 DOI: 10.21203/rs.3.rs-4814547/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/17/2024]
Abstract
RNA molecules perform a diversity of essential functions for which their linear sequences must fold into higher-order structures. Techniques including crystallography and cryogenic electron microscopy have revealed 3D structures of ribosomal, transfer, and other well-structured RNAs; while chemical probing with sequencing facilitates secondary structure modeling of any RNAs of interest, even within cells. Ongoing efforts continue increasing the accuracy, resolution, and ability to distinguish coexisting alternative structures. However, no method can discover and quantify alternative structures with base pairs spanning arbitrarily long distances - an obstacle for studying viral, messenger, and long noncoding RNAs, which may form long-range base pairs. Here, we introduce the method of Structure Ensemble Ablation by Reverse Complement Hybridization with Mutational Profiling (SEARCH-MaP) and software for Structure Ensemble Inference by Sequencing, Mutation Identification, and Clustering of RNA (SEISMIC-RNA). We use SEARCH-MaP and SEISMIC-RNA to discover that the frameshift stimulating element of SARS coronavirus 2 base-pairs with another element 1 kilobase downstream in nearly half of RNA molecules, and that this structure competes with a pseudoknot that stimulates ribosomal frameshifting. Moreover, we identify long-range base pairs involving the frameshift stimulating element in other coronaviruses including SARS coronavirus 1 and transmissible gastroenteritis virus, and model the full genomic secondary structure of the latter. These findings suggest that long-range base pairs are common in coronaviruses and may regulate ribosomal frameshifting, which is essential for viral RNA synthesis. We anticipate that SEARCH-MaP will enable solving many RNA structure ensembles that have eluded characterization, thereby enhancing our general understanding of RNA structures and their functions. SEISMIC-RNA, software for analyzing mutational profiling data at any scale, could power future studies on RNA structure and is available on GitHub and the Python Package Index.
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Affiliation(s)
- Matthew F. Allan
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA 02115
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA 02139
- Computational and Systems Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA 02139
| | - Justin Aruda
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA 02115
- Harvard Program in Biological and Biomedical Sciences, Division of Medical Sciences, Harvard Medical School, Boston, MA, USA 02115
| | - Jesse S. Plung
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA 02115
- Harvard Program in Virology, Division of Medical Sciences, Harvard Medical School, Boston, MA, USA 02115
| | - Scott L. Grote
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA 02115
| | | | - Albéric A. de Lajarte
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA 02115
| | - Mark Bathe
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA 02139
| | - Silvi Rouskin
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA 02115
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5
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Baliga-Gil A, Soszynska-Jozwiak M, Ruszkowska A, Szczesniak I, Kierzek R, Ciechanowska M, Trybus M, Jackowiak P, Peterson JM, Moss WN, Kierzek E. Targeting sgRNA N secondary structure as a way of inhibiting SARS-CoV-2 replication. Antiviral Res 2024; 228:105946. [PMID: 38925369 DOI: 10.1016/j.antiviral.2024.105946] [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: 01/20/2024] [Revised: 06/07/2024] [Accepted: 06/22/2024] [Indexed: 06/28/2024]
Abstract
SARS-CoV-2 is a betacoronavirus that causes COVID-19, a global pandemic that has resulted in many infections, deaths, and socio-economic challenges. The virus has a large positive-sense, single-stranded RNA genome of ∼30 kb, which produces subgenomic RNAs (sgRNAs) through discontinuous transcription. The most abundant sgRNA is sgRNA N, which encodes the nucleocapsid (N) protein. In this study, we probed the secondary structure of sgRNA N and a shorter model without a 3' UTR in vitro, using the SHAPE (selective 2'-hydroxyl acylation analyzed by a primer extension) method and chemical mapping with dimethyl sulfate and 1-cyclohexyl-(2-morpholinoethyl) carbodiimide metho-p-toluene sulfonate. We revealed the secondary structure of sgRNA N and its shorter variant for the first time and compared them with the genomic RNA N structure. Based on the structural information, we designed gapmers, siRNAs and antisense oligonucleotides (ASOs) to target the N protein coding region of sgRNA N. We also generated eukaryotic expression vectors containing the complete sequence of sgRNA N and used them to screen for new SARS-CoV-2 gene N expression inhibitors. Our study provides novel insights into the structure and function of sgRNA N and potential therapeutic tools against SARS-CoV-2.
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Affiliation(s)
- Agnieszka Baliga-Gil
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704, Poznan, Poland
| | - Marta Soszynska-Jozwiak
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704, Poznan, Poland
| | - Agnieszka Ruszkowska
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704, Poznan, Poland
| | - Izabela Szczesniak
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704, Poznan, Poland
| | - Ryszard Kierzek
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704, Poznan, Poland
| | - Maria Ciechanowska
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704, Poznan, Poland
| | - Magdalena Trybus
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704, Poznan, Poland
| | - Paulina Jackowiak
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704, Poznan, Poland
| | - Jake M Peterson
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, IA, 50011, USA
| | - Walter N Moss
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, IA, 50011, USA
| | - Elzbieta Kierzek
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704, Poznan, Poland.
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6
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Allan MF, Aruda J, Plung JS, Grote SL, Martin des Taillades YJ, de Lajarte AA, Bathe M, Rouskin S. Discovery and Quantification of Long-Range RNA Base Pairs in Coronavirus Genomes with SEARCH-MaP and SEISMIC-RNA. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.29.591762. [PMID: 38746332 PMCID: PMC11092567 DOI: 10.1101/2024.04.29.591762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
RNA molecules perform a diversity of essential functions for which their linear sequences must fold into higher-order structures. Techniques including crystallography and cryogenic electron microscopy have revealed 3D structures of ribosomal, transfer, and other well-structured RNAs; while chemical probing with sequencing facilitates secondary structure modeling of any RNAs of interest, even within cells. Ongoing efforts continue increasing the accuracy, resolution, and ability to distinguish coexisting alternative structures. However, no method can discover and quantify alternative structures with base pairs spanning arbitrarily long distances - an obstacle for studying viral, messenger, and long noncoding RNAs, which may form long-range base pairs. Here, we introduce the method of Structure Ensemble Ablation by Reverse Complement Hybridization with Mutational Profiling (SEARCH-MaP) and software for Structure Ensemble Inference by Sequencing, Mutation Identification, and Clustering of RNA (SEISMIC-RNA). We use SEARCH-MaP and SEISMIC-RNA to discover that the frameshift stimulating element of SARS coronavirus 2 base-pairs with another element 1 kilobase downstream in nearly half of RNA molecules, and that this structure competes with a pseudoknot that stimulates ribosomal frameshifting. Moreover, we identify long-range base pairs involving the frameshift stimulating element in other coronaviruses including SARS coronavirus 1 and transmissible gastroenteritis virus, and model the full genomic secondary structure of the latter. These findings suggest that long-range base pairs are common in coronaviruses and may regulate ribosomal frameshifting, which is essential for viral RNA synthesis. We anticipate that SEARCH-MaP will enable solving many RNA structure ensembles that have eluded characterization, thereby enhancing our general understanding of RNA structures and their functions. SEISMIC-RNA, software for analyzing mutational profiling data at any scale, could power future studies on RNA structure and is available on GitHub and the Python Package Index.
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7
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Rahman MM, Ryan CA, Tessier BR, Rozners E. Peptide nucleic acids (PNAs) control function of SARS-CoV-2 frameshifting stimulatory element trough PNA-RNA-PNA triplex formation. Heliyon 2024; 10:e33914. [PMID: 39071573 PMCID: PMC11282987 DOI: 10.1016/j.heliyon.2024.e33914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2024] [Revised: 05/30/2024] [Accepted: 06/28/2024] [Indexed: 07/30/2024] Open
Abstract
The highly structured nature of the SARS-CoV-2 genome provides many promising antiviral drug targets. One particularly promising target is a cis-acting RNA pseudoknot found within a critical region called the frameshifting stimulatory element (FSE). In this study, peptide nucleic acids (PNAs) binding to stem 2 of FSE RNA inhibited protein translation and frameshifting, as measured by a cell-free dual luciferase assay, more effectively than PNAs binding to stem 1, stem 3, or the slippery site. Surprisingly, simple antisense PNAs were stronger disruptors of frameshifting than PNA tail-clamps, despite higher thermal stability of the PNA-RNA-PNA triplexes formed by the latter. Another unexpected result was a strong and sequence non-specific enhancement of frameshifting inhibition when using a cationic triplex-forming PNA in conjunction with an antisense PNA targeting key regions of the frameshifting element. Our results illustrate both the potential and the challenges of using antisense PNAs to target highly structured RNAs, such as SARS-CoV-2 pseudoknots. While triplex forming PNAs, including PNA tail-clamps, are emerging as promising ligands for RNA recognition, the binding affinity enhancements when using cationic modifications in triplex-forming PNAs must be carefully balanced to avoid loss of sequence specificity in complex biological systems.
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Affiliation(s)
| | | | - Brandon R. Tessier
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, NY, 13902, United States
| | - Eriks Rozners
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, NY, 13902, United States
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8
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Lee S, Yan S, Dey A, Laederach A, Schlick T. An intricate balancing act: Upstream and downstream frameshift co-regulatory elements. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.27.599960. [PMID: 38979256 PMCID: PMC11230384 DOI: 10.1101/2024.06.27.599960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
Targeting ribosomal frameshifting has emerged as a potential therapeutic intervention strategy against Covid-19. During ribosomal translation, a fraction of elongating ribosomes slips by one base in the 5' direction and enters a new reading frame for viral protein synthesis. Any interference with this process profoundly affects viral replication and propagation. For Covid-19, two RNA sites associated with ribosomal frameshifting for SARS-CoV-2 are positioned on the 5' and 3' of the frameshifting residues. Although much attention has been on the 3' frameshift element (FSE), the 5' stem-loop (attenuator hairpin, AH) can play a role. The formation of AH has been suggested to occur as refolding of the 3' RNA structure is triggered by ribosomal unwinding. However, the attenuation activity and the relationship between the two regions are unknown. To gain more insight into these two related viral RNAs and to further enrich our understanding of ribosomal frameshifting for SARS-CoV-2, we explore the RNA folding of both 5' and 3' regions associated with frameshifting. Using our graph-theory-based modeling tools to represent RNA secondary structures, "RAG" (RNA- As-Graphs), and conformational landscapes to analyze length-dependent conformational distributions, we show that AH coexists with the 3-stem pseudoknot of the 3' FSE (graph 3_6 in our dual graph notation) and alternative pseudoknot (graph 3_3) but less likely with other 3' FSE alternative folds (such as 3-way junction 3_5). This is because an alternative length-dependent Stem 1 (AS1) can disrupt the FSE pseudoknots and trigger other folds. In addition, we design four mutants for long lengths that stabilize or disrupt AH, AS1 or FSE pseudoknot to illustrate the deduced AH/AS1 roles and favor the 3_5, 3_6 or stem-loop. These mutants further show how a strengthened pseudoknot can result from a weakened AS1, while a dominant stem-loop occurs with a strengthened AS1. These structural and mutational insights into both ends of the FSE in SARS-CoV-2 advance our understanding of the SARS-CoV-2 frameshifting mechanism by suggesting a sequence of length-dependent folds, which in turn define potential therapeutic intervention techniques involving both elements. Our work also highlights the complexity of viral landscapes with length-dependent folds, and challenges in analyzing these multiple conformations.
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Affiliation(s)
- Samuel Lee
- Department of Chemistry, New York University, New York, 10003, NY, U.S.A
| | - Shuting Yan
- Department of Chemistry, New York University, New York, 10003, NY, U.S.A
| | - Abhishek Dey
- Department of Biotechnology, National Institute of Pharmaceutical Education and Research-Raebareli (NIPER-R), Lucknow, 226002, Uttar Pradesh, India
| | - Alain Laederach
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, 27599, NC, U.S.A
| | - Tamar Schlick
- Department of Chemistry, New York University, New York, 10003, NY, U.S.A
- Courant Institute of Mathematical Sciences, New York University, New York, 10012, NY, U.S.A
- NYU-ECNU Center for Computational Chemistry, NYU Shanghai, Shanghai, 200062, P.R.China
- NYU Simons Center for Computational Physical Chemistry, New York University, New York, 10003, NY, U.S.A
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9
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Li H, Li J, Li J, Li H, Wang X, Jiang J, Lei L, Sun H, Tang M, Dong B, He W, Si S, Hong B, Li Y, Song D, Peng Z, Che Y, Jiang JD. Carrimycin inhibits coronavirus replication by decreasing the efficiency of programmed -1 ribosomal frameshifting through directly binding to the RNA pseudoknot of viral frameshift-stimulatory element. Acta Pharm Sin B 2024; 14:2567-2580. [PMID: 38828157 PMCID: PMC11143517 DOI: 10.1016/j.apsb.2024.02.023] [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: 10/18/2023] [Revised: 01/08/2024] [Accepted: 02/04/2024] [Indexed: 06/05/2024] Open
Abstract
The pandemic of SARS-CoV-2 worldwide with successive emerging variants urgently calls for small-molecule oral drugs with broad-spectrum antiviral activity. Here, we show that carrimycin, a new macrolide antibiotic in the clinic and an antiviral candidate for SARS-CoV-2 in phase III trials, decreases the efficiency of programmed -1 ribosomal frameshifting of coronaviruses and thus impedes viral replication in a broad-spectrum fashion. Carrimycin binds directly to the coronaviral frameshift-stimulatory element (FSE) RNA pseudoknot, interrupting the viral protein translation switch from ORF1a to ORF1b and thereby reducing the level of the core components of the viral replication and transcription complexes. Combined carrimycin with known viral replicase inhibitors yielded a synergistic inhibitory effect on coronaviruses. Because the FSE mechanism is essential in all coronaviruses, carrimycin could be a new broad-spectrum antiviral drug for human coronaviruses by directly targeting the conserved coronaviral FSE RNA. This finding may open a new direction in antiviral drug discovery for coronavirus variants.
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Affiliation(s)
- Hongying Li
- CAMS Key Laboratory of Antiviral Drug Research, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
| | - Jianrui Li
- CAMS Key Laboratory of Antiviral Drug Research, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
| | - Jiayu Li
- CAMS Key Laboratory of Antiviral Drug Research, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
| | - Hu Li
- CAMS Key Laboratory of Antiviral Drug Research, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
- Key Laboratory of Biotechnology of Antibiotics, the National Health and Family Planning Commission (NHFPC), Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
| | - Xuekai Wang
- CAMS Key Laboratory of Antiviral Drug Research, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
| | - Jing Jiang
- CAMS Key Laboratory of Antiviral Drug Research, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
| | - Lei Lei
- CAMS Key Laboratory of Antiviral Drug Research, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
| | - Han Sun
- CAMS Key Laboratory of Antiviral Drug Research, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
| | - Mei Tang
- CAMS Key Laboratory of Antiviral Drug Research, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
| | - Biao Dong
- CAMS Key Laboratory of Antiviral Drug Research, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
- Key Laboratory of Biotechnology of Antibiotics, the National Health and Family Planning Commission (NHFPC), Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
| | - Weiqing He
- Key Laboratory of Biotechnology of Antibiotics, the National Health and Family Planning Commission (NHFPC), Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
| | - Shuyi Si
- Key Laboratory of Biotechnology of Antibiotics, the National Health and Family Planning Commission (NHFPC), Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
| | - Bin Hong
- Key Laboratory of Biotechnology of Antibiotics, the National Health and Family Planning Commission (NHFPC), Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
| | - Yinghong Li
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
| | - Danqing Song
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
| | - Zonggen Peng
- CAMS Key Laboratory of Antiviral Drug Research, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
- Key Laboratory of Biotechnology of Antibiotics, the National Health and Family Planning Commission (NHFPC), Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
| | - Yongsheng Che
- Key Laboratory of Biotechnology of Antibiotics, the National Health and Family Planning Commission (NHFPC), Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
| | - Jian-Dong Jiang
- CAMS Key Laboratory of Antiviral Drug Research, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
- Key Laboratory of Biotechnology of Antibiotics, the National Health and Family Planning Commission (NHFPC), Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
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10
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Trinity L, Stege U, Jabbari H. Tying the knot: Unraveling the intricacies of the coronavirus frameshift pseudoknot. PLoS Comput Biol 2024; 20:e1011787. [PMID: 38713726 PMCID: PMC11108256 DOI: 10.1371/journal.pcbi.1011787] [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: 12/27/2023] [Revised: 05/21/2024] [Accepted: 04/27/2024] [Indexed: 05/09/2024] Open
Abstract
Understanding and targeting functional RNA structures towards treatment of coronavirus infection can help us to prepare for novel variants of SARS-CoV-2 (the virus causing COVID-19), and any other coronaviruses that could emerge via human-to-human transmission or potential zoonotic (inter-species) events. Leveraging the fact that all coronaviruses use a mechanism known as -1 programmed ribosomal frameshifting (-1 PRF) to replicate, we apply algorithms to predict the most energetically favourable secondary structures (each nucleotide involved in at most one pairing) that may be involved in regulating the -1 PRF event in coronaviruses, especially SARS-CoV-2. We compute previously unknown most stable structure predictions for the frameshift site of coronaviruses via hierarchical folding, a biologically motivated framework where initial non-crossing structure folds first, followed by subsequent, possibly crossing (pseudoknotted), structures. Using mutual information from 181 coronavirus sequences, in conjunction with the algorithm KnotAli, we compute secondary structure predictions for the frameshift site of different coronaviruses. We then utilize the Shapify algorithm to obtain most stable SARS-CoV-2 secondary structure predictions guided by frameshift sequence-specific and genome-wide experimental data. We build on our previous secondary structure investigation of the singular SARS-CoV-2 68 nt frameshift element sequence, by using Shapify to obtain predictions for 132 extended sequences and including covariation information. Previous investigations have not applied hierarchical folding to extended length SARS-CoV-2 frameshift sequences. By doing so, we simulate the effects of ribosome interaction with the frameshift site, providing insight to biological function. We contribute in-depth discussion to contextualize secondary structure dual-graph motifs for SARS-CoV-2, highlighting the energetic stability of the previously identified 3_8 motif alongside the known dominant 3_3 and 3_6 (native-type) -1 PRF structures. Using a combination of thermodynamic methods and sequence covariation, our novel predictions suggest function of the attenuator hairpin via previously unknown pseudoknotted base pairing. While certain initial RNA folding is consistent, other pseudoknotted base pairs form which indicate potential conformational switching between the two structures.
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Affiliation(s)
- Luke Trinity
- Department of Computer Science, University of Victoria, Victoria, British Columbia, Canada
| | - Ulrike Stege
- Department of Computer Science, University of Victoria, Victoria, British Columbia, Canada
| | - Hosna Jabbari
- Department of Biomedical Engineering, University of Alberta, Edmonton, Alberta, Canada
- Institute on Aging and Lifelong Health, Victoria, British Columbia, Canada
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11
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Marinus T, Foster TL, Tych KM. The application of single-molecule optical tweezers to study disease-related structural dynamics in RNA. Biochem Soc Trans 2024; 52:899-909. [PMID: 38533854 PMCID: PMC11088911 DOI: 10.1042/bst20231232] [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: 12/29/2023] [Revised: 03/01/2024] [Accepted: 03/08/2024] [Indexed: 03/28/2024]
Abstract
RNA, a dynamic and flexible molecule with intricate three-dimensional structures, has myriad functions in disease development. Traditional methods, such as X-ray crystallography and nuclear magnetic resonance, face limitations in capturing real-time, single-molecule dynamics crucial for understanding RNA function. This review explores the transformative potential of single-molecule force spectroscopy using optical tweezers, showcasing its capability to directly probe time-dependent structural rearrangements of individual RNA molecules. Optical tweezers offer versatility in exploring diverse conditions, with the potential to provide insights into how environmental changes, ligands and RNA-binding proteins impact RNA behaviour. By enabling real-time observations of large-scale structural dynamics, optical tweezers emerge as an invaluable tool for advancing our comprehension of RNA structure and function. Here, we showcase their application in elucidating the dynamics of RNA elements in virology, such as the pseudoknot governing ribosomal frameshifting in SARS-CoV-2.
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Affiliation(s)
- Tycho Marinus
- Chemical Biology 1, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Toshana L. Foster
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, University of Nottingham, LE12 5RD Loughborough, U.K
| | - Katarzyna M. Tych
- Chemical Biology 1, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
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12
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Ren G, Gu X, Zhang L, Gong S, Song S, Chen S, Chen Z, Wang X, Li Z, Zhou Y, Li L, Yang J, Lai F, Dang Y. Ribosomal frameshifting at normal codon repeats recodes functional chimeric proteins in human. Nucleic Acids Res 2024; 52:2463-2479. [PMID: 38281188 PMCID: PMC10954444 DOI: 10.1093/nar/gkae035] [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: 08/10/2023] [Revised: 01/04/2024] [Accepted: 01/10/2024] [Indexed: 01/30/2024] Open
Abstract
Ribosomal frameshifting refers to the process that ribosomes slip into +1 or -1 reading frame, thus produce chimeric trans-frame proteins. In viruses and bacteria, programmed ribosomal frameshifting can produce essential trans-frame proteins for viral replication or regulation of other biological processes. In humans, however, functional trans-frame protein derived from ribosomal frameshifting is scarcely documented. Combining multiple assays, we show that short codon repeats could act as cis-acting elements that stimulate ribosomal frameshifting in humans, abbreviated as CRFS hereafter. Using proteomic analyses, we identified many putative CRFS events from 32 normal human tissues supported by trans-frame peptides positioned at codon repeats. Finally, we show a CRFS-derived trans-frame protein (HDAC1-FS) functions by antagonizing the activities of HDAC1, thus affecting cell migration and apoptosis. These data suggest a novel type of translational recoding associated with codon repeats, which may expand the coding capacity of mRNA and diversify the regulation in human.
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Affiliation(s)
- Guiping Ren
- State Key Laboratory for Conservation and Utilization of Bio-Resource in Yunnan, Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan Key Laboratory of Cell Metabolism and Diseases, Center for Life Science, School of Life Sciences, Yunnan University, Kunming 650021, China
- Southwest United Graduate School, Kunming650092, China
| | - Xiaoqian Gu
- State Key Laboratory for Conservation and Utilization of Bio-Resource in Yunnan, Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan Key Laboratory of Cell Metabolism and Diseases, Center for Life Science, School of Life Sciences, Yunnan University, Kunming 650021, China
- Southwest United Graduate School, Kunming650092, China
| | - Lu Zhang
- State Key Laboratory for Conservation and Utilization of Bio-Resource in Yunnan, Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan Key Laboratory of Cell Metabolism and Diseases, Center for Life Science, School of Life Sciences, Yunnan University, Kunming 650021, China
- Southwest United Graduate School, Kunming650092, China
| | - Shimin Gong
- State Key Laboratory for Conservation and Utilization of Bio-Resource in Yunnan, Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan Key Laboratory of Cell Metabolism and Diseases, Center for Life Science, School of Life Sciences, Yunnan University, Kunming 650021, China
- Southwest United Graduate School, Kunming650092, China
| | - Shuang Song
- State Key Laboratory for Conservation and Utilization of Bio-Resource in Yunnan, Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan Key Laboratory of Cell Metabolism and Diseases, Center for Life Science, School of Life Sciences, Yunnan University, Kunming 650021, China
- Southwest United Graduate School, Kunming650092, China
| | - Shunkai Chen
- State Key Laboratory for Conservation and Utilization of Bio-Resource in Yunnan, Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan Key Laboratory of Cell Metabolism and Diseases, Center for Life Science, School of Life Sciences, Yunnan University, Kunming 650021, China
- Southwest United Graduate School, Kunming650092, China
| | - Zhenjing Chen
- State Key Laboratory for Conservation and Utilization of Bio-Resource in Yunnan, Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan Key Laboratory of Cell Metabolism and Diseases, Center for Life Science, School of Life Sciences, Yunnan University, Kunming 650021, China
- Southwest United Graduate School, Kunming650092, China
| | - Xiaoyan Wang
- State Key Laboratory for Conservation and Utilization of Bio-Resource in Yunnan, Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan Key Laboratory of Cell Metabolism and Diseases, Center for Life Science, School of Life Sciences, Yunnan University, Kunming 650021, China
- Southwest United Graduate School, Kunming650092, China
| | - Zhanbiao Li
- State Key Laboratory for Conservation and Utilization of Bio-Resource in Yunnan, Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan Key Laboratory of Cell Metabolism and Diseases, Center for Life Science, School of Life Sciences, Yunnan University, Kunming 650021, China
- Southwest United Graduate School, Kunming650092, China
| | - Yingshui Zhou
- State Key Laboratory for Conservation and Utilization of Bio-Resource in Yunnan, Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan Key Laboratory of Cell Metabolism and Diseases, Center for Life Science, School of Life Sciences, Yunnan University, Kunming 650021, China
- Southwest United Graduate School, Kunming650092, China
| | - Longxi Li
- State Key Laboratory for Conservation and Utilization of Bio-Resource in Yunnan, Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan Key Laboratory of Cell Metabolism and Diseases, Center for Life Science, School of Life Sciences, Yunnan University, Kunming 650021, China
- Southwest United Graduate School, Kunming650092, China
| | - Jiao Yang
- State Key Laboratory for Conservation and Utilization of Bio-Resource in Yunnan, Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan Key Laboratory of Cell Metabolism and Diseases, Center for Life Science, School of Life Sciences, Yunnan University, Kunming 650021, China
- Southwest United Graduate School, Kunming650092, China
| | - Fan Lai
- State Key Laboratory for Conservation and Utilization of Bio-Resource in Yunnan, Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan Key Laboratory of Cell Metabolism and Diseases, Center for Life Science, School of Life Sciences, Yunnan University, Kunming 650021, China
- Southwest United Graduate School, Kunming650092, China
| | - Yunkun Dang
- State Key Laboratory for Conservation and Utilization of Bio-Resource in Yunnan, Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan Key Laboratory of Cell Metabolism and Diseases, Center for Life Science, School of Life Sciences, Yunnan University, Kunming 650021, China
- Southwest United Graduate School, Kunming650092, China
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13
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Halma MTJ, Xu L. Life under tension: the relevance of force on biological polymers. BIOPHYSICS REPORTS 2024; 10:48-56. [PMID: 38737478 PMCID: PMC11079598 DOI: 10.52601/bpr.2023.230019] [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: 10/11/2023] [Accepted: 12/06/2023] [Indexed: 05/14/2024] Open
Abstract
Optical tweezers have elucidated numerous biological processes, particularly by enabling the precise manipulation and measurement of tension. One question concerns the biological relevance of these experiments and the generalizability of these experiments to wider biological systems. Here, we categorize the applicability of the information garnered from optical tweezers in two distinct categories: the direct relevance of tension in biological systems, and what experiments under tension can tell us about biological systems, while these systems do not reach the same tension as the experiment, still, these artificial experimental systems reveal insights into the operations of biological machines and life processes.
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Affiliation(s)
- Matthew T. J. Halma
- Department of Physics and Astronomy and LaserLab, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV, Amsterdam, the Netherlands
- LUMICKS B. V., 1081 HV, Amsterdam, the Netherlands
| | - Longfu Xu
- Department of Physics and Astronomy and LaserLab, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV, Amsterdam, the Netherlands
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14
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Karousis ED, Schubert K, Ban N. Coronavirus takeover of host cell translation and intracellular antiviral response: a molecular perspective. EMBO J 2024; 43:151-167. [PMID: 38200146 PMCID: PMC10897431 DOI: 10.1038/s44318-023-00019-8] [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: 06/01/2023] [Revised: 11/01/2023] [Accepted: 11/24/2023] [Indexed: 01/12/2024] Open
Abstract
Coronaviruses are a group of related RNA viruses that cause respiratory diseases in humans and animals. Understanding the mechanisms of translation regulation during coronaviral infections is critical for developing antiviral therapies and preventing viral spread. Translation of the viral single-stranded RNA genome in the host cell cytoplasm is an essential step in the life cycle of coronaviruses, which affects the cellular mRNA translation landscape in many ways. Here we discuss various viral strategies of translation control, including how members of the Betacoronavirus genus shut down host cell translation and suppress host innate immune functions, as well as the role of the viral non-structural protein 1 (Nsp1) in the process. We also outline the fate of viral RNA, considering stress response mechanisms triggered in infected cells, and describe how unique viral RNA features contribute to programmed ribosomal -1 frameshifting, RNA editing, and translation shutdown evasion.
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Affiliation(s)
- Evangelos D Karousis
- Multidisciplinary Center for Infectious Diseases, University of Bern, Bern, Switzerland
- Department of Chemistry and Biochemistry, University of Bern, Bern, Switzerland
| | - Katharina Schubert
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zurich, Zurich, Switzerland
| | - Nenad Ban
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zurich, Zurich, Switzerland.
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15
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Kelly JA, Dinman JD. Shiftless Is a Novel Member of the Ribosome Stress Surveillance Machinery That Has Evolved to Play a Role in Innate Immunity and Cancer Surveillance. Viruses 2023; 15:2296. [PMID: 38140537 PMCID: PMC10747187 DOI: 10.3390/v15122296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 11/20/2023] [Accepted: 11/21/2023] [Indexed: 12/24/2023] Open
Abstract
A longstanding paradox in molecular biology has centered on the question of how very long proteins are synthesized, despite numerous measurements indicating that ribosomes spontaneously shift reading frame at rates that should preclude their ability completely translate their mRNAs. Shiftless (SFL; C19orf66) was originally identified as an interferon responsive gene encoding an antiviral protein, indicating that it is part of the innate immune response. This activity is due to its ability to bind ribosomes that have been programmed by viral sequence elements to shift reading frame. Curiously, Shiftless is constitutively expressed at low levels in mammalian cells. This study examines the effects of altering Shiftless homeostasis, revealing how it may be used by higher eukaryotes to identify and remove spontaneously frameshifted ribosomes, resolving the apparent limitation on protein length. Data also indicate that Shiftless plays a novel role in the ribosome-associated quality control program. A model is proposed wherein SFL recognizes and arrests frameshifted ribosomes, and depending on SFL protein concentrations, either leads to removal of frameshifted ribosomes while leaving mRNAs intact, or to mRNA degradation. We propose that SFL be added to the growing pantheon of proteins involved in surveilling translational fidelity and controlling gene expression in higher eukaryotes.
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Affiliation(s)
| | - Jonathan D. Dinman
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA;
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16
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Knizhnik E, Chumakov S, Svetlova J, Pavlova I, Khodarovich Y, Brylev V, Severov V, Alieva R, Kozlovskaya L, Andreev D, Aralov A, Varizhuk A. Unwinding the SARS-CoV-2 Ribosomal Frameshifting Pseudoknot with LNA and G-Clamp-Modified Phosphorothioate Oligonucleotides Inhibits Viral Replication. Biomolecules 2023; 13:1660. [PMID: 38002341 PMCID: PMC10668963 DOI: 10.3390/biom13111660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2023] [Revised: 11/10/2023] [Accepted: 11/15/2023] [Indexed: 11/26/2023] Open
Abstract
Ribosomal frameshifting (RFS) at the slippery site of SARS-CoV-2 RNA is essential for the biosynthesis of the viral replication machinery. It requires the formation of a pseudoknot (PK) structure near the slippery site and can be inhibited by PK-disrupting oligonucleotide-based antivirals. We obtained and compared three types of such antiviral candidates, namely locked nucleic acids (LNA), LNA-DNA gapmers, and G-clamp-containing phosphorothioates (CPSs) complementary to PK stems. Using optical and electrophoretic methods, we showed that stem 2-targeting oligonucleotide analogs induced PK unfolding at nanomolar concentrations, and this effect was particularly pronounced in the case of LNA. For the leading PK-unfolding LNA and CPS oligonucleotide analogs, we also demonstrated dose-dependent RSF inhibition in dual luciferase assays (DLAs). Finally, we showed that the leading oligonucleotide analogs reduced SARS-CoV-2 replication at subtoxic concentrations in the nanomolar range in two human cell lines. Our findings highlight the promise of PK targeting, illustrate the advantages and limitations of various types of DNA modifications and may promote the future development of oligonucleotide-based antivirals.
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Affiliation(s)
- Ekaterina Knizhnik
- Lopukhin Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, 119435 Moscow, Russia; (E.K.); (J.S.); (I.P.); (V.S.)
- Department of Biological and Medical Physics, Moscow Institute of Physics and Technology, 141701 Dolgoprudny, Russia
| | - Stepan Chumakov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia; (S.C.); (Y.K.); (V.B.); (D.A.)
| | - Julia Svetlova
- Lopukhin Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, 119435 Moscow, Russia; (E.K.); (J.S.); (I.P.); (V.S.)
| | - Iulia Pavlova
- Lopukhin Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, 119435 Moscow, Russia; (E.K.); (J.S.); (I.P.); (V.S.)
- Department of Biological and Medical Physics, Moscow Institute of Physics and Technology, 141701 Dolgoprudny, Russia
| | - Yuri Khodarovich
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia; (S.C.); (Y.K.); (V.B.); (D.A.)
- Research and Educational Resource Center for Cellular Technologies of The Peoples’ Friendship University of Russia, 117198 Moscow, Russia
| | - Vladimir Brylev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia; (S.C.); (Y.K.); (V.B.); (D.A.)
| | - Vjacheslav Severov
- Lopukhin Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, 119435 Moscow, Russia; (E.K.); (J.S.); (I.P.); (V.S.)
| | - Rugiya Alieva
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119992 Moscow, Russia;
- Raman Spectroscopy Laboratory, Moscow Institute of Physics and Technology, 141701 Dolgoprudny, Russia
| | - Liubov Kozlovskaya
- Chumakov Scientific Center for Research and Development of Immune-and-Biological Products, Russian Academy of Sciences (Institute of Poliomyelitis), 108819 Moscow, Russia;
| | - Dmitry Andreev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia; (S.C.); (Y.K.); (V.B.); (D.A.)
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119992 Moscow, Russia;
| | - Andrey Aralov
- Lopukhin Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, 119435 Moscow, Russia; (E.K.); (J.S.); (I.P.); (V.S.)
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia; (S.C.); (Y.K.); (V.B.); (D.A.)
| | - Anna Varizhuk
- Lopukhin Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, 119435 Moscow, Russia; (E.K.); (J.S.); (I.P.); (V.S.)
- Department of Biological and Medical Physics, Moscow Institute of Physics and Technology, 141701 Dolgoprudny, Russia
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17
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He W, San Emeterio J, Woodside MT, Kirmizialtin S, Pollack L. Atomistic structure of the SARS-CoV-2 pseudoknot in solution from SAXS-driven molecular dynamics. Nucleic Acids Res 2023; 51:11332-11344. [PMID: 37819014 PMCID: PMC10639041 DOI: 10.1093/nar/gkad809] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 08/31/2023] [Accepted: 09/21/2023] [Indexed: 10/13/2023] Open
Abstract
SARS-CoV-2 depends on -1 programmed ribosomal frameshifting (-1 PRF) to express proteins essential for its replication. The RNA pseudoknot stimulating -1 PRF is thus an attractive drug target. However, the structural models of this pseudoknot obtained from cryo-EM and crystallography differ in some important features, leaving the pseudoknot structure unclear. We measured the solution structure of the pseudoknot using small-angle X-ray scattering (SAXS). The measured profile did not agree with profiles computed from the previously solved structures. Beginning with each of these solved structures, we used the SAXS data to direct all atom molecular dynamics (MD) simulations to improve the agreement in profiles. In all cases, this refinement resulted in a bent conformation that more closely resembled the cryo-EM structures than the crystal structure. Applying the same approach to a point mutant abolishing -1 PRF revealed a notably more bent structure with reoriented helices. This work clarifies the dynamic structures of the SARS-CoV-2 pseudoknot in solution.
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Affiliation(s)
- Weiwei He
- Chemistry Program, Science Division, New York University, Abu Dhabi, United Arab Emirates
- Department of Chemistry, New York University, USA
| | | | - Michael T Woodside
- Department of Physics, Li Ka Shing Institute of Virology, and Centre for Prions and Protein Folding Diseases, University of Alberta, Canada
| | - Serdal Kirmizialtin
- Chemistry Program, Science Division, New York University, Abu Dhabi, United Arab Emirates
- Department of Chemistry, New York University, USA
| | - Lois Pollack
- School of Applied and Engineering Physics, Cornell University, USA
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18
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Abstract
Protein synthesis by the ribosome is the final stage of biological information transfer and represents an irreversible commitment to gene expression. Accurate translation of messenger RNA is therefore essential to all life, and spontaneous errors by the translational machinery are highly infrequent (∼1/100,000 codons). Programmed -1 ribosomal frameshifting (-1PRF) is a mechanism in which the elongating ribosome is induced at high frequency to slip backward by one nucleotide at a defined position and to continue translation in the new reading frame. This is exploited as a translational regulation strategy by hundreds of RNA viruses, which rely on -1PRF during genome translation to control the stoichiometry of viral proteins. While early investigations of -1PRF focused on virological and biochemical aspects, the application of X-ray crystallography and cryo-electron microscopy (cryo-EM), and the advent of deep sequencing and single-molecule approaches have revealed unexpected structural diversity and mechanistic complexity. Molecular players from several model systems have now been characterized in detail, both in isolation and, more recently, in the context of the elongating ribosome. Here we provide a summary of recent advances and discuss to what extent a general model for -1PRF remains a useful way of thinking.
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Affiliation(s)
- Chris H Hill
- York Structural Biology Laboratory, York Biomedical Research Institute, Department of Biology, University of York, York, United Kingdom;
| | - Ian Brierley
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom;
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19
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Cerri A, Bolatti EM, Zorec TM, Montani ME, Rimondi A, Hosnjak L, Casal PE, Di Domenica V, Barquez RM, Poljak M, Giri AA. Identification and characterization of novel alphacoronaviruses in Tadarida brasiliensis (Chiroptera, Molossidae) from Argentina: insights into recombination as a mechanism favoring bat coronavirus cross-species transmission. Microbiol Spectr 2023; 11:e0204723. [PMID: 37695063 PMCID: PMC10581097 DOI: 10.1128/spectrum.02047-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 07/14/2023] [Indexed: 09/12/2023] Open
Abstract
Bats are reservoirs of various coronaviruses that can jump between bat species or other mammalian hosts, including humans. This article explores coronavirus infection in three bat species (Tadarida brasiliensis, Eumops bonariensis, and Molossus molossus) of the family Molossidae from Argentina using whole viral metagenome analysis. Fecal samples of 47 bats from three semiurban or highly urbanized areas of the province of Santa Fe were investigated. After viral particle enrichment, total RNA was sequenced using the Illumina NextSeq 550 instrument; the reads were assembled into contigs and taxonomically and phylogenetically analyzed. Three novel complete Alphacoronavirus (AlphaCoV) genomes (Tb1-3) and two partial sequences were identified in T. brasiliensis (Tb4-5), and an additional four partial sequences were identified in M. molossus (Mm1-4). Phylogenomic analysis showed that the novel AlphaCoV clustered in two different lineages distinct from the 15 officially recognized AlphaCoV subgenera. Tb2 and Tb3 isolates appeared to be variants of the same virus, probably involved in a persistent infectious cycle within the T. brasiliensis colony. Using recombination analysis, we detected a statistically significant event in Spike gene, which was reinforced by phylogenetic tree incongruence analysis, involving novel Tb1 and AlphaCoVs identified in Eptesicus fuscus (family Vespertilionidae) from the U.S. The putative recombinant region is in the S1 subdomain of the Spike gene, encompassing the potential receptor-binding domain of AlphaCoVs. This study reports the first AlphaCoV genomes in molossids from the Americas and provides new insights into recombination as an important mode of evolution of coronaviruses involved in cross-species transmission. IMPORTANCE This study generated three novel complete AlphaCoV genomes (Tb1, Tb2, and Tb3 isolates) identified in individuals of Tadarida brasiliensis from Argentina, which showed two different evolutionary patterns and are the first to be reported in the family Molossidae in the Americas. The novel Tb1 isolate was found to be involved in a putative recombination event with alphacoronaviruses identified in bats of the genus Eptesicus from the U.S., whereas isolates Tb2 and Tb3 were found in different collection seasons and might be involved in persistent viral infections in the bat colony. These findings contribute to our knowledge of the global diversity of bat coronaviruses in poorly studied species and highlight the different evolutionary aspects of AlphaCoVs circulating in bat populations in Argentina.
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Affiliation(s)
- Agustina Cerri
- Human Virology Group, Rosario Institute of Molecular and Cellular Biology (IBR-CONICET), Rosario, Argentina
| | - Elisa M. Bolatti
- Human Virology Group, Rosario Institute of Molecular and Cellular Biology (IBR-CONICET), Rosario, Argentina
- Virology Area, Faculty of Biochemical and Pharmaceutical Sciences, National University of Rosario, Rosario, Argentina
- Bat Conservation Program of Argentina, San Miguel de Tucumán, Argentina
| | - Tomaz M. Zorec
- Institute of Microbiology and Immunology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Maria E. Montani
- Bat Conservation Program of Argentina, San Miguel de Tucumán, Argentina
- Dr. Ángel Gallardo Provincial Museum of Natural Sciences, Rosario, Argentina
- Argentine Biodiversity Research Institute (PIDBA), Faculty of Natural Sciences, National University of Tucumán, San Miguel de Tucumán, Argentina
| | - Agustina Rimondi
- Institute of Virology and Technological Innovations (INTA/CONICET), Castelar, Argentina
- Robert Koch Institute, Berlin, Germany
| | - Lea Hosnjak
- Institute of Microbiology and Immunology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Pablo E. Casal
- DETx MOL S.A. La Segunda Núcleo Corporate Building, Alvear, Argentina
| | - Violeta Di Domenica
- Human Virology Group, Rosario Institute of Molecular and Cellular Biology (IBR-CONICET), Rosario, Argentina
- Bat Conservation Program of Argentina, San Miguel de Tucumán, Argentina
| | - Ruben M. Barquez
- Bat Conservation Program of Argentina, San Miguel de Tucumán, Argentina
- Argentine Biodiversity Research Institute (PIDBA), Faculty of Natural Sciences, National University of Tucumán, San Miguel de Tucumán, Argentina
| | - Mario Poljak
- Institute of Microbiology and Immunology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Adriana A. Giri
- Human Virology Group, Rosario Institute of Molecular and Cellular Biology (IBR-CONICET), Rosario, Argentina
- Virology Area, Faculty of Biochemical and Pharmaceutical Sciences, National University of Rosario, Rosario, Argentina
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20
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Poulis P, Peske F, Rodnina MV. The many faces of ribosome translocation along the mRNA: reading frame maintenance, ribosome frameshifting and translational bypassing. Biol Chem 2023; 404:755-767. [PMID: 37077160 DOI: 10.1515/hsz-2023-0142] [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: 02/21/2023] [Accepted: 03/22/2023] [Indexed: 04/21/2023]
Abstract
In each round of translation elongation, the ribosome translocates along the mRNA by precisely one codon. Translocation is promoted by elongation factor G (EF-G) in bacteria (eEF2 in eukaryotes) and entails a number of precisely-timed large-scale structural rearrangements. As a rule, the movements of the ribosome, tRNAs, mRNA and EF-G are orchestrated to maintain the exact codon-wise step size. However, signals in the mRNA, as well as environmental cues, can change the timing and dynamics of the key rearrangements leading to recoding of the mRNA into production of trans-frame peptides from the same mRNA. In this review, we discuss recent advances on the mechanics of translocation and reading frame maintenance. Furthermore, we describe the mechanisms and biological relevance of non-canonical translocation pathways, such as hungry and programmed frameshifting and translational bypassing, and their link to disease and infection.
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Affiliation(s)
- Panagiotis Poulis
- Department of Physical Biochemistry, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, D-37077 Göttingen, Germany
| | - Frank Peske
- Department of Physical Biochemistry, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, D-37077 Göttingen, Germany
| | - Marina V Rodnina
- Department of Physical Biochemistry, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, D-37077 Göttingen, Germany
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21
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Sekar RV, Oliva PJ, Woodside MT. Modelling the structures of frameshift-stimulatory pseudoknots from representative bat coronaviruses. PLoS Comput Biol 2023; 19:e1011124. [PMID: 37205708 DOI: 10.1371/journal.pcbi.1011124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 04/24/2023] [Indexed: 05/21/2023] Open
Abstract
Coronaviruses (CoVs) use -1 programmed ribosomal frameshifting stimulated by RNA pseudoknots in the viral genome to control expression of enzymes essential for replication, making CoV pseudoknots a promising target for anti-coronaviral drugs. Bats represent one of the largest reservoirs of CoVs and are the ultimate source of most CoVs infecting humans, including those causing SARS, MERS, and COVID-19. However, the structures of bat-CoV frameshift-stimulatory pseudoknots remain largely unexplored. Here we use a combination of blind structure prediction followed by all-atom molecular dynamics simulations to model the structures of eight pseudoknots that, together with the SARS-CoV-2 pseudoknot, are representative of the range of pseudoknot sequences in bat CoVs. We find that they all share some key qualitative features with the pseudoknot from SARS-CoV-2, notably the presence of conformers with two distinct fold topologies differing in whether or not the 5' end of the RNA is threaded through a junction, and similar conformations for stem 1. However, they differed in the number of helices present, with half sharing the 3-helix architecture of the SARS-CoV-2 pseudoknot but two containing 4 helices and two others only 2. These structure models should be helpful for future work studying bat-CoV pseudoknots as potential therapeutic targets.
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Affiliation(s)
| | | | - Michael T Woodside
- Department of Physics, University of Alberta, Edmonton, Canada
- Li Ka Shing Institute of Virology, University of Alberta, Edmonton, Canada
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Canada
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22
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Allan MF, Brivanlou A, Rouskin S. RNA levers and switches controlling viral gene expression. Trends Biochem Sci 2023; 48:391-406. [PMID: 36710231 DOI: 10.1016/j.tibs.2022.12.002] [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: 09/12/2022] [Revised: 11/27/2022] [Accepted: 12/15/2022] [Indexed: 01/29/2023]
Abstract
RNA viruses are diverse and abundant pathogens that are responsible for numerous human diseases. RNA viruses possess relatively compact genomes and have therefore evolved multiple mechanisms to maximize their coding capacities, often by encoding overlapping reading frames. These reading frames are then decoded by mechanisms such as alternative splicing and ribosomal frameshifting to produce multiple distinct proteins. These solutions are enabled by the ability of the RNA genome to fold into 3D structures that can mimic cellular RNAs, hijack host proteins, and expose or occlude regulatory protein-binding motifs to ultimately control key process in the viral life cycle. We highlight recent findings focusing on less conventional mechanisms of gene expression and new discoveries on the role of RNA structures.
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Affiliation(s)
- Matthew F Allan
- Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA; Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Computational and Systems Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Amir Brivanlou
- Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA
| | - Silvi Rouskin
- Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA.
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23
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Trinity L, Wark I, Lansing L, Jabbari H, Stege U. Shapify: Paths to SARS-CoV-2 frameshifting pseudoknot. PLoS Comput Biol 2023; 19:e1010922. [PMID: 36854032 PMCID: PMC10004594 DOI: 10.1371/journal.pcbi.1010922] [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: 10/04/2022] [Revised: 03/10/2023] [Accepted: 02/05/2023] [Indexed: 03/02/2023] Open
Abstract
Multiple coronaviruses including MERS-CoV causing Middle East Respiratory Syndrome, SARS-CoV causing SARS, and SARS-CoV-2 causing COVID-19, use a mechanism known as -1 programmed ribosomal frameshifting (-1 PRF) to replicate. SARS-CoV-2 possesses a unique RNA pseudoknotted structure that stimulates -1 PRF. Targeting -1 PRF in SARS-CoV-2 to impair viral replication can improve patients' prognoses. Crucial to developing these therapies is understanding the structure of the SARS-CoV-2 -1 PRF pseudoknot. Our goal is to expand knowledge of -1 PRF structural conformations. Following a structural alignment approach, we identify similarities in -1 PRF pseudoknots of SARS-CoV-2, SARS-CoV, and MERS-CoV. We provide in-depth analysis of the SARS-CoV-2 and MERS-CoV -1 PRF pseudoknots, including reference and noteworthy mutated sequences. To better understand the impact of mutations, we provide insight on -1 PRF pseudoknot sequence mutations and their effect on resulting structures. We introduce Shapify, a novel algorithm that given an RNA sequence incorporates structural reactivity (SHAPE) data and partial structure information to output an RNA secondary structure prediction within a biologically sound hierarchical folding approach. Shapify enhances our understanding of SARS-CoV-2 -1 PRF pseudoknot conformations by providing energetically favourable predictions that are relevant to structure-function and may correlate with -1 PRF efficiency. Applied to the SARS-CoV-2 -1 PRF pseudoknot, Shapify unveils previously unknown paths from initial stems to pseudoknotted structures. By contextualizing our work with available experimental data, our structure predictions motivate future RNA structure-function research and can aid 3-D modeling of pseudoknots.
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Affiliation(s)
- Luke Trinity
- Department of Computer Science, University of Victoria, Victoria, British Columbia, Canada
| | - Ian Wark
- Department of Computing Science, University of Alberta, Edmonton, Alberta, Canada
| | - Lance Lansing
- Department of Computer Science, University of Victoria, Victoria, British Columbia, Canada
| | - Hosna Jabbari
- Department of Computer Science, University of Victoria, Victoria, British Columbia, Canada
- Department of Computing Science, University of Alberta, Edmonton, Alberta, Canada
- Institute on Aging and Lifelong Health, Victoria, British Columbia, Canada
| | - Ulrike Stege
- Department of Computer Science, University of Victoria, Victoria, British Columbia, Canada
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24
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Szczesniak I, Baliga-Gil A, Jarmolowicz A, Soszynska-Jozwiak M, Kierzek E. Structural and Functional RNA Motifs of SARS-CoV-2 and Influenza A Virus as a Target of Viral Inhibitors. Int J Mol Sci 2023; 24:ijms24021232. [PMID: 36674746 PMCID: PMC9860923 DOI: 10.3390/ijms24021232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 12/28/2022] [Accepted: 12/29/2022] [Indexed: 01/11/2023] Open
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the COVID-19 pandemic, whereas the influenza A virus (IAV) causes seasonal epidemics and occasional pandemics. Both viruses lead to widespread infection and death. SARS-CoV-2 and the influenza virus are RNA viruses. The SARS-CoV-2 genome is an approximately 30 kb, positive sense, 5' capped single-stranded RNA molecule. The influenza A virus genome possesses eight single-stranded negative-sense segments. The RNA secondary structure in the untranslated and coding regions is crucial in the viral replication cycle. The secondary structure within the RNA of SARS-CoV-2 and the influenza virus has been intensively studied. Because the whole of the SARS-CoV-2 and influenza virus replication cycles are dependent on RNA with no DNA intermediate, the RNA is a natural and promising target for the development of inhibitors. There are a lot of RNA-targeting strategies for regulating pathogenic RNA, such as small interfering RNA for RNA interference, antisense oligonucleotides, catalytic nucleic acids, and small molecules. In this review, we summarized the knowledge about the inhibition of SARS-CoV-2 and influenza A virus propagation by targeting their RNA secondary structure.
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25
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Pekarek L, Zimmer MM, Gribling-Burrer AS, Buck S, Smyth R, Caliskan N. Cis-mediated interactions of the SARS-CoV-2 frameshift RNA alter its conformations and affect function. Nucleic Acids Res 2022; 51:728-743. [PMID: 36537211 PMCID: PMC9881162 DOI: 10.1093/nar/gkac1184] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 11/11/2022] [Accepted: 12/13/2022] [Indexed: 12/24/2022] Open
Abstract
The RNA genome of SARS-CoV-2 contains a frameshift stimulatory element (FSE) that allows access to an alternative reading frame through -1 programmed ribosomal frameshifting (PRF). -1PRF in the 1a/1b gene is essential for efficient viral replication and transcription of the viral genome. -1PRF efficiency relies on the presence of conserved RNA elements within the FSE. One of these elements is a three-stemmed pseudoknot, although alternative folds of the frameshift site might have functional roles as well. Here, by complementing ensemble and single-molecule structural analysis of SARS-CoV-2 frameshift RNA variants with functional data, we reveal a conformational interplay of the 5' and 3' immediate regions with the FSE and show that the extended FSE exists in multiple conformations. Furthermore, limiting the base pairing of the FSE with neighboring nucleotides can favor or impair the formation of the alternative folds, including the pseudoknot. Our results demonstrate that co-existing RNA structures can function together to fine-tune SARS-CoV-2 gene expression, which will aid efforts to design specific inhibitors of viral frameshifting.
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Affiliation(s)
- Lukas Pekarek
- Helmholtz Institute for RNA-based Infection Research (HIRI-HZI), Würzburg, Germany
| | | | | | | | - Redmond Smyth
- Correspondence may also be addressed to Redmond Smyth.
| | - Neva Caliskan
- To whom correspondence should be addressed. Tel: +49 931 318 5298;
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26
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Focus on Marine Animal Safety and Marine Bioresources in Response to the SARS-CoV-2 Crisis. Int J Mol Sci 2022; 23:ijms232315136. [PMID: 36499463 PMCID: PMC9737530 DOI: 10.3390/ijms232315136] [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: 10/18/2022] [Revised: 11/18/2022] [Accepted: 11/29/2022] [Indexed: 12/04/2022] Open
Abstract
SARS-CoV-2 as a zoonotic virus has significantly affected daily life and social behavior since its outbreak in late 2019. The concerns over its transmission through different media directly or indirectly have evoked great attention about the survival of SARS-CoV-2 virions in the environment and its potential infection of other animals. To evaluate the risk of infection by SARS-CoV-2 and to counteract the COVID-19 disease, extensive studies have been performed to understand SARS-CoV-2 biogenesis and its pathogenesis. This review mainly focuses on the molecular architecture of SARS-CoV-2, its potential for infecting marine animals, and the prospect of drug discovery using marine natural products to combat SARS-CoV-2. The main purposes of this review are to piece together progress in SARS-CoV-2 functional genomic studies and antiviral drug development, and to raise our awareness of marine animal safety on exposure to SARS-CoV-2.
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27
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Simba-Lahuasi A, Cantero-Camacho Á, Rosales R, McGovern BL, Rodríguez ML, Marchán V, White KM, García-Sastre A, Gallego J. SARS-CoV-2 Inhibitors Identified by Phenotypic Analysis of a Collection of Viral RNA-Binding Molecules. Pharmaceuticals (Basel) 2022; 15:1448. [PMID: 36558898 PMCID: PMC9784969 DOI: 10.3390/ph15121448] [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: 10/13/2022] [Revised: 11/16/2022] [Accepted: 11/18/2022] [Indexed: 11/23/2022] Open
Abstract
Antiviral agents are needed for the treatment of SARS-CoV-2 infections and to control other coronavirus outbreaks that may occur in the future. Here we report the identification and characterization of RNA-binding compounds that inhibit SARS-CoV-2 replication. The compounds were detected by screening a small library of antiviral compounds previously shown to bind HIV-1 or HCV RNA elements with a live-virus cellular assay detecting inhibition of SARS-CoV-2 replication. These experiments allowed detection of eight compounds with promising anti-SARS-CoV-2 activity in the sub-micromolar to micromolar range and wide selectivity indexes. Examination of the mechanism of action of three selected hit compounds excluded action on the entry or egress stages of the virus replication cycle and confirmed recognition by two of the molecules of conserved RNA elements of the SARS-CoV-2 genome, including the highly conserved S2m hairpin located in the 3'-untranslated region of the virus. While further studies are needed to clarify the mechanism of action responsible for antiviral activity, these results facilitate the discovery of RNA-targeted antivirals and provide new chemical scaffolds for developing therapeutic agents against coronaviruses.
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Affiliation(s)
- Alvaro Simba-Lahuasi
- Centro de Investigación Traslacional San Alberto Magno, Universidad Católica de Valencia, 46001 Valencia, Spain
- Escuela de Doctorado, Universidad Católica de Valencia, 46001 Valencia, Spain
| | - Ángel Cantero-Camacho
- Centro de Investigación Traslacional San Alberto Magno, Universidad Católica de Valencia, 46001 Valencia, Spain
| | - Romel Rosales
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Global Health Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Briana Lynn McGovern
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Global Health Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - M. Luis Rodríguez
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Global Health Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Vicente Marchán
- Departament de Química Inorgànica i Orgànica, Secció de Química Orgànica, Institut de Biomedicina (IBUB), Universitat de Barcelona (UB), 08028 Barcelona, Spain
| | - Kris M. White
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Global Health Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Adolfo García-Sastre
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Global Health Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Department of Medicine, Division of Infectious Diseases, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Tish Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Department of Pathology, Molecular and Cell Based Medicine, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - José Gallego
- Centro de Investigación Traslacional San Alberto Magno, Universidad Católica de Valencia, 46001 Valencia, Spain
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28
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Rolband L, Beasock D, Wang Y, Shu YG, Dinman JD, Schlick T, Zhou Y, Kieft JS, Chen SJ, Bussi G, Oukhaled A, Gao X, Šulc P, Binzel D, Bhullar AS, Liang C, Guo P, Afonin KA. Biomotors, viral assembly, and RNA nanobiotechnology: Current achievements and future directions. Comput Struct Biotechnol J 2022; 20:6120-6137. [PMID: 36420155 PMCID: PMC9672130 DOI: 10.1016/j.csbj.2022.11.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 11/04/2022] [Accepted: 11/04/2022] [Indexed: 11/13/2022] Open
Abstract
The International Society of RNA Nanotechnology and Nanomedicine (ISRNN) serves to further the development of a wide variety of functional nucleic acids and other related nanotechnology platforms. To aid in the dissemination of the most recent advancements, a biennial discussion focused on biomotors, viral assembly, and RNA nanobiotechnology has been established where international experts in interdisciplinary fields such as structural biology, biophysical chemistry, nanotechnology, cell and cancer biology, and pharmacology share their latest accomplishments and future perspectives. The results summarized here highlight advancements in our understanding of viral biology and the structure-function relationship of frame-shifting elements in genomic viral RNA, improvements in the predictions of SHAPE analysis of 3D RNA structures, and the understanding of dynamic RNA structures through a variety of experimental and computational means. Additionally, recent advances in the drug delivery, vaccine design, nanopore technologies, biomotor and biomachine development, DNA packaging, RNA nanotechnology, and drug delivery are included in this critical review. We emphasize some of the novel accomplishments, major discussion topics, and present current challenges and perspectives of these emerging fields.
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Affiliation(s)
- Lewis Rolband
- University of North Carolina at Charlotte, Charlotte, NC 28223, USA
| | - Damian Beasock
- University of North Carolina at Charlotte, Charlotte, NC 28223, USA
| | - Yang Wang
- Wenzhou Institute, University of China Academy of Sciences, 1st, Jinlian Road, Longwan District, Wenzhou, Zhjiang 325001, China
| | - Yao-Gen Shu
- Wenzhou Institute, University of China Academy of Sciences, 1st, Jinlian Road, Longwan District, Wenzhou, Zhjiang 325001, China
| | | | - Tamar Schlick
- New York University, Department of Chemistry and Courant Institute of Mathematical Sciences, Simons Center for Computational Physical Chemistry, New York, NY 10012, USA
| | - Yaoqi Zhou
- Institute for Systems and Physical Biology, Shenzhen Bay Laboratory, Shenzhen, Guangdong 518107, China
| | - Jeffrey S. Kieft
- University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Shi-Jie Chen
- University of Missouri at Columbia, Columbia, MO 65211, USA
| | - Giovanni Bussi
- Scuola Internazionale Superiore di Studi Avanzati, via Bonomea 265, 34136 Trieste, Italy
| | | | - Xingfa Gao
- National Center for Nanoscience and Technology of China, Beijing 100190, China
| | - Petr Šulc
- Arizona State University, Tempe, AZ, USA
| | | | | | - Chenxi Liang
- The Ohio State University, Columbus, OH 43210, USA
| | - Peixuan Guo
- The Ohio State University, Columbus, OH 43210, USA
| | - Kirill A. Afonin
- University of North Carolina at Charlotte, Charlotte, NC 28223, USA
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29
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Arriaga-Canon C, Contreras-Espinosa L, Rebollar-Vega R, Montiel-Manríquez R, Cedro-Tanda A, García-Gordillo JA, Álvarez-Gómez RM, Jiménez-Trejo F, Castro-Hernández C, Herrera LA. Transcriptomics and RNA-Based Therapeutics as Potential Approaches to Manage SARS-CoV-2 Infection. Int J Mol Sci 2022; 23:11058. [PMID: 36232363 PMCID: PMC9570475 DOI: 10.3390/ijms231911058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 09/13/2022] [Accepted: 09/14/2022] [Indexed: 11/24/2022] Open
Abstract
SARS-CoV-2 is a coronavirus family member that appeared in China in December 2019 and caused the disease called COVID-19, which was declared a pandemic in 2020 by the World Health Organization. In recent months, great efforts have been made in the field of basic and clinical research to understand the biology and infection processes of SARS-CoV-2. In particular, transcriptome analysis has contributed to generating new knowledge of the viral sequences and intracellular signaling pathways that regulate the infection and pathogenesis of SARS-CoV-2, generating new information about its biology. Furthermore, transcriptomics approaches including spatial transcriptomics, single-cell transcriptomics and direct RNA sequencing have been used for clinical applications in monitoring, detection, diagnosis, and treatment to generate new clinical predictive models for SARS-CoV-2. Consequently, RNA-based therapeutics and their relationship with SARS-CoV-2 have emerged as promising strategies to battle the SARS-CoV-2 pandemic with the assistance of novel approaches such as CRISPR-CAS, ASOs, and siRNA systems. Lastly, we discuss the importance of precision public health in the management of patients infected with SARS-CoV-2 and establish that the fusion of transcriptomics, RNA-based therapeutics, and precision public health will allow a linkage for developing health systems that facilitate the acquisition of relevant clinical strategies for rapid decision making to assist in the management and treatment of the SARS-CoV-2-infected population to combat this global public health problem.
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Affiliation(s)
- Cristian Arriaga-Canon
- Unidad de Investigación Biomédica en Cáncer, Instituto Nacional de Cancerología-Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México (UNAM), Avenida San Fernando No. 22 ColC. Sección XVI, Tlalpan. C.P., Mexico City 14080, Mexico
| | - Laura Contreras-Espinosa
- Unidad de Investigación Biomédica en Cáncer, Instituto Nacional de Cancerología-Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México (UNAM), Avenida San Fernando No. 22 ColC. Sección XVI, Tlalpan. C.P., Mexico City 14080, Mexico
| | - Rosa Rebollar-Vega
- Genomics Laboratory, Red de Apoyo a la Investigación, Universidad Nacional Autónoma de México, Vasco de Quiroga 15, Belisario Domínguez Secc 16, Tlalpan, Mexico City 14080, Mexico
| | - Rogelio Montiel-Manríquez
- Unidad de Investigación Biomédica en Cáncer, Instituto Nacional de Cancerología-Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México (UNAM), Avenida San Fernando No. 22 ColC. Sección XVI, Tlalpan. C.P., Mexico City 14080, Mexico
| | - Alberto Cedro-Tanda
- Instituto Nacional de Medicina Genómica, Periférico Sur 4809, Arenal Tepepan, Tlalpan. C.P., Mexico City 14610, Mexico
| | - José Antonio García-Gordillo
- Oncología Médica, Instituto Nacional de Cancerología, Avenida San Fernando No. 22 Col. Sección XVI, Tlalpan. C.P., Mexico City 14080, Mexico
| | - Rosa María Álvarez-Gómez
- Clínica de Cáncer Hereditario, Instituto Nacional de Cancerología, Avenida San Fernando No. 22 Col. Sección XVI, Tlalpan. C.P., Mexico City 14080, Mexico
| | - Francisco Jiménez-Trejo
- Instituto Nacional de Pediatría, Insurgentes Sur No. 3700-C, Coyoacán. C.P., Mexico City 04530, Mexico
| | - Clementina Castro-Hernández
- Unidad de Investigación Biomédica en Cáncer, Instituto Nacional de Cancerología-Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México (UNAM), Avenida San Fernando No. 22 ColC. Sección XVI, Tlalpan. C.P., Mexico City 14080, Mexico
| | - Luis A. Herrera
- Unidad de Investigación Biomédica en Cáncer, Instituto Nacional de Cancerología-Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México (UNAM), Avenida San Fernando No. 22 ColC. Sección XVI, Tlalpan. C.P., Mexico City 14080, Mexico
- Instituto Nacional de Medicina Genómica, Periférico Sur 4809, Arenal Tepepan, Tlalpan. C.P., Mexico City 14610, Mexico
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30
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Yadav V. Computational evidence based perspective on the plausible repositioning of fluoroquinolones for COVID-19 treatment. Curr Comput Aided Drug Des 2022; 18:CAD-EPUB-126248. [PMID: 36093826 DOI: 10.2174/1573409918666220909094645] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 06/13/2022] [Accepted: 07/22/2022] [Indexed: 11/22/2022]
Abstract
The coronavirus disease (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has become a serious global healthcare crisis, so there is an emergence of identifying efficacious therapeutic options. In a setting where there is an unavailability of definitive medication along with the constant eruption of vaccine-related controversies, the drug-repositioning approach seems to be an ideal step for the management of COVID-19 patients. Fluoroquinolones (FQs) are commonly prescribed antibiotics for the treatment of genitourinary tract and upper respiratory tract infections, including severe community-acquired pneumonia. Research over the years has postulated multifaceted implications of FQs in various pathological conditions. Previously, it has been reported that few, but not all FQs, possess strong antiviral activity with an unknown mechanism of action. Herein, an interesting perspective is discussed on repositioning possibilities of FQs for the SARS-CoV-2 infections based on the recent in silico evidential support. Noteworthy, FQs possess immunomodulatory and bactericidal activity which could be valuable for patients dealing with COVID-19 related complications. Conclusively, the current perspective could pave the way to initiate pre-clinical testing of FQs against several strains of SARS-CoV-2.
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Affiliation(s)
- Vikas Yadav
- Interdisciplinary Cluster for Applied Genoproteomics (GIGA), University of Liège, Sart-Tilman, 4000, Liège, Belgium
- Department of Translational Medicine, Skane University Hospital, Clinical Research Centre, Lund University, Malmö, Sweden
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31
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Romero Romero ML, Landerer C, Poehls J, Toth‐Petroczy A. Phenotypic mutations contribute to protein diversity and shape protein evolution. Protein Sci 2022; 31:e4397. [PMID: 36040266 PMCID: PMC9375231 DOI: 10.1002/pro.4397] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 06/14/2022] [Accepted: 07/04/2022] [Indexed: 11/16/2022]
Abstract
Errors in DNA replication generate genetic mutations, while errors in transcription and translation lead to phenotypic mutations. Phenotypic mutations are orders of magnitude more frequent than genetic ones, yet they are less understood. Here, we review the types of phenotypic mutations, their quantifications, and their role in protein evolution and disease. The diversity generated by phenotypic mutation can facilitate adaptive evolution. Indeed, phenotypic mutations, such as ribosomal frameshift and stop codon readthrough, sometimes serve to regulate protein expression and function. Phenotypic mutations have often been linked to fitness decrease and diseases. Thus, understanding the protein heterogeneity and phenotypic diversity caused by phenotypic mutations will advance our understanding of protein evolution and have implications on human health and diseases.
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Affiliation(s)
- Maria Luisa Romero Romero
- Max Planck Institute of Molecular Cell Biology and GeneticsDresdenGermany
- Center for Systems Biology DresdenDresdenGermany
| | - Cedric Landerer
- Max Planck Institute of Molecular Cell Biology and GeneticsDresdenGermany
- Center for Systems Biology DresdenDresdenGermany
| | - Jonas Poehls
- Max Planck Institute of Molecular Cell Biology and GeneticsDresdenGermany
- Center for Systems Biology DresdenDresdenGermany
| | - Agnes Toth‐Petroczy
- Max Planck Institute of Molecular Cell Biology and GeneticsDresdenGermany
- Center for Systems Biology DresdenDresdenGermany
- Cluster of Excellence Physics of LifeTU DresdenDresdenGermany
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32
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Length-dependent motions of SARS-CoV-2 frameshifting RNA pseudoknot and alternative conformations suggest avenues for frameshifting suppression. Nat Commun 2022; 13:4284. [PMID: 35879278 PMCID: PMC9310368 DOI: 10.1038/s41467-022-31353-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 06/10/2022] [Indexed: 12/16/2022] Open
Abstract
The SARS-CoV-2 frameshifting element (FSE), a highly conserved mRNA region required for correct translation of viral polyproteins, defines an excellent therapeutic target against Covid-19. As discovered by our prior graph-theory analysis with SHAPE experiments, the FSE adopts a heterogeneous, length-dependent conformational landscape consisting of an assumed 3-stem H-type pseudoknot (graph motif 3_6), and two alternative motifs (3_3 and 3_5). Here, for the first time, we build and simulate, by microsecond molecular dynamics, 30 models for all three motifs plus motif-stabilizing mutants at different lengths. Our 3_6 pseudoknot systems, which agree with experimental structures, reveal interconvertible L and linear conformations likely related to ribosomal pausing and frameshifting. The 3_6 mutant inhibits this transformation and could hamper frameshifting. Our 3_3 systems exhibit length-dependent stem interactions that point to a potential transition pathway connecting the three motifs during ribosomal elongation. Together, our observations provide new insights into frameshifting mechanisms and anti-viral strategies.
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33
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Nafamostat-Mediated Inhibition of SARS-CoV-2 Ribosomal Frameshifting Is Insufficient to Impair Viral Replication in Vero Cells. Comment on Munshi et al. Identifying Inhibitors of −1 Programmed Ribosomal Frameshifting in a Broad Spectrum of Coronaviruses. Viruses 2022, 14, 177. Viruses 2022; 14:v14071526. [PMID: 35891506 PMCID: PMC9324898 DOI: 10.3390/v14071526] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 07/07/2022] [Accepted: 07/08/2022] [Indexed: 12/21/2022] Open
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34
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Lessons Learned and Yet-to-Be Learned on the Importance of RNA Structure in SARS-CoV-2 Replication. Microbiol Mol Biol Rev 2022; 86:e0005721. [PMID: 35862724 PMCID: PMC9491204 DOI: 10.1128/mmbr.00057-21] [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] [Indexed: 11/30/2022] Open
Abstract
SARS-CoV-2, the etiological agent responsible for the COVID-19 pandemic, is a member of the virus family Coronaviridae, known for relatively extensive (~30-kb) RNA genomes that not only encode for numerous proteins but are also capable of forming elaborate structures. As highlighted in this review, these structures perform critical functions in various steps of the viral life cycle, ultimately impacting pathogenesis and transmissibility. We examine these elements in the context of coronavirus evolutionary history and future directions for curbing the spread of SARS-CoV-2 and other potential human coronaviruses. While we focus on structures supported by a variety of biochemical, biophysical, and/or computational methods, we also touch here on recent evidence for novel structures in both protein-coding and noncoding regions of the genome, including an assessment of the potential role for RNA structure in the controversial finding of SARS-CoV-2 integration in “long COVID” patients. This review aims to serve as a consolidation of previous works on coronavirus and more recent investigation of SARS-CoV-2, emphasizing the need for improved understanding of the role of RNA structure in the evolution and adaptation of these human viruses.
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35
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Zhang D, Zhu L, Wang Y, Li P, Gao Y. Translational Control of COVID-19 and Its Therapeutic Implication. Front Immunol 2022; 13:857490. [PMID: 35422818 PMCID: PMC9002053 DOI: 10.3389/fimmu.2022.857490] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 03/07/2022] [Indexed: 12/19/2022] Open
Abstract
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of COVID-19, which has broken out worldwide for more than two years. However, due to limited treatment, new cases of infection are still rising. Therefore, there is an urgent need to understand the basic molecular biology of SARS-CoV-2 to control this virus. SARS-CoV-2 replication and spread depend on the recruitment of host ribosomes to translate viral messenger RNA (mRNA). To ensure the translation of their own mRNAs, the SARS-CoV-2 has developed multiple strategies to globally inhibit the translation of host mRNAs and block the cellular innate immune response. This review provides a comprehensive picture of recent advancements in our understanding of the molecular basis and complexity of SARS-CoV-2 protein translation. Specifically, we summarize how this viral infection inhibits host mRNA translation to better utilize translation elements for translation of its own mRNA. Finally, we discuss the potential of translational components as targets for therapeutic interventions.
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Affiliation(s)
- Dejiu Zhang
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, China
| | - Lei Zhu
- College of Basic Medical, Qingdao Binhai University, Qingdao, China
| | - Yin Wang
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, China
| | - Peifeng Li
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, China
| | - Yanyan Gao
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, China
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36
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Bao C, Zhu M, Nykonchuk I, Wakabayashi H, Mathews DH, Ermolenko DN. Specific length and structure rather than high thermodynamic stability enable regulatory mRNA stem-loops to pause translation. Nat Commun 2022; 13:988. [PMID: 35190568 PMCID: PMC8861025 DOI: 10.1038/s41467-022-28600-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 02/03/2022] [Indexed: 11/09/2022] Open
Abstract
AbstractTranslating ribosomes unwind mRNA secondary structures by three basepairs each elongation cycle. Despite the ribosome helicase, certain mRNA stem-loops stimulate programmed ribosomal frameshift by inhibiting translation elongation. Here, using mutagenesis, biochemical and single-molecule experiments, we examine whether high stability of three basepairs, which are unwound by the translating ribosome, is critical for inducing ribosome pauses. We find that encountering frameshift-inducing mRNA stem-loops from the E. coli dnaX mRNA and the gag-pol transcript of Human Immunodeficiency Virus (HIV) hinders A-site tRNA binding and slows down ribosome translocation by 15-20 folds. By contrast, unwinding of first three basepairs adjacent to the mRNA entry channel slows down the translating ribosome by only 2-3 folds. Rather than high thermodynamic stability, specific length and structure enable regulatory mRNA stem-loops to stall translation by forming inhibitory interactions with the ribosome. Our data provide the basis for rationalizing transcriptome-wide studies of translation and searching for novel regulatory mRNA stem-loops.
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37
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Zhang H, Fischer DK, Shuda M, Moore PS, Gao SJ, Ambrose Z, Guo H. Construction and characterization of two SARS-CoV-2 minigenome replicon systems. J Med Virol 2022; 94:2438-2452. [PMID: 35137972 PMCID: PMC9088700 DOI: 10.1002/jmv.27650] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Revised: 02/02/2022] [Accepted: 02/03/2022] [Indexed: 11/10/2022]
Abstract
The ongoing COVID-19 pandemic severely impacts global public health and economies. In order to facilitate research on SARS-CoV-2 virology and antiviral discovery, a non-infectious viral replicon system operating under biosafety level 2 containment is warranted. We report herein the construction and characterization of two SARS-CoV-2 minigenome replicon systems. First, we constructed the IVT-CoV2-Rep cDNA template to generate a replicon mRNA with nanoluciferase (NLuc) reporter via in vitro transcription (IVT). The replicon mRNA transfection assay demonstrated a rapid and transient replication of IVT-CoV2-Rep in a variety of cell lines, which could be completely abolished by known SARS-CoV-2 replication inhibitors. Our data also suggests that the transient phenotype of IVT-CoV2-Rep is not due to host innate antiviral responses. In addition, we have developed a DNA-launched replicon BAC-CoV2-Rep, which supports the in-cell transcription of a replicon mRNA as initial replication template. The BAC-CoV2-Rep transient transfection system exhibited a much stronger and longer replicon signal compared to the IVT-CoV2-Rep version. We also found that a portion of the NLuc reporter signal was derived from the spliced BAC-CoV2-Rep mRNA and was resistant to antiviral treatment, especially during the early phase after transfection. In summary, the established SARS-CoV-2 transient replicon systems are suitable for basic and antiviral research, and hold promise for stable replicon cell line development with further optimization. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Hu Zhang
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine.,Cancer Virology Program, Hillman Cancer Center, University of Pittsburgh Medical Center
| | - Douglas K Fischer
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine.,Cancer Virology Program, Hillman Cancer Center, University of Pittsburgh Medical Center
| | - Masahiro Shuda
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine.,Cancer Virology Program, Hillman Cancer Center, University of Pittsburgh Medical Center
| | - Patrick S Moore
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine.,Cancer Virology Program, Hillman Cancer Center, University of Pittsburgh Medical Center
| | - Shou-Jiang Gao
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine.,Cancer Virology Program, Hillman Cancer Center, University of Pittsburgh Medical Center
| | - Zandrea Ambrose
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine.,Cancer Virology Program, Hillman Cancer Center, University of Pittsburgh Medical Center
| | - Haitao Guo
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine.,Cancer Virology Program, Hillman Cancer Center, University of Pittsburgh Medical Center
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38
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Jones CP, Ferré-D'Amaré AR. Crystal structure of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) frameshifting pseudoknot. RNA (NEW YORK, N.Y.) 2022; 28:239-249. [PMID: 34845084 PMCID: PMC8906546 DOI: 10.1261/rna.078825.121] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 11/04/2021] [Indexed: 05/30/2023]
Abstract
SARS-CoV-2 produces two long viral protein precursors from one open reading frame using a highly conserved RNA pseudoknot that enhances programmed -1 ribosomal frameshifting. The 1.3 Å-resolution X-ray structure of the pseudoknot reveals three coaxially stacked helices buttressed by idiosyncratic base triples from loop residues. This structure represents a frameshift-stimulating state that must be deformed by the ribosome and exhibits base-triple-adjacent pockets that could be targeted by future small-molecule therapeutics.
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Affiliation(s)
- Christopher P Jones
- Biochemistry and Biophysics Center, National Heart, Lung and Blood Institute, Bethesda, Maryland 20892, USA
| | - Adrian R Ferré-D'Amaré
- Biochemistry and Biophysics Center, National Heart, Lung and Blood Institute, Bethesda, Maryland 20892, USA
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39
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Identifying Inhibitors of −1 Programmed Ribosomal Frameshifting in a Broad Spectrum of Coronaviruses. Viruses 2022; 14:v14020177. [PMID: 35215770 PMCID: PMC8876150 DOI: 10.3390/v14020177] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 12/30/2021] [Accepted: 01/10/2022] [Indexed: 02/06/2023] Open
Abstract
Recurrent outbreaks of novel zoonotic coronavirus (CoV) diseases in recent years have highlighted the importance of developing therapeutics with broad-spectrum activity against CoVs. Because all CoVs use −1 programmed ribosomal frameshifting (−1 PRF) to control expression of key viral proteins, the frameshift signal in viral mRNA that stimulates −1 PRF provides a promising potential target for such therapeutics. To test the viability of this strategy, we explored whether small-molecule inhibitors of −1 PRF in SARS-CoV-2 also inhibited −1 PRF in a range of bat CoVs—the most likely source of future zoonoses. Six inhibitors identified in new and previous screens against SARS-CoV-2 were evaluated against the frameshift signals from a panel of representative bat CoVs as well as MERS-CoV. Some drugs had strong activity against subsets of these CoV-derived frameshift signals, while having limited to no effect on −1 PRF caused by frameshift signals from other viruses used as negative controls. Notably, the serine protease inhibitor nafamostat suppressed −1 PRF significantly for multiple CoV-derived frameshift signals. These results suggest it is possible to find small-molecule ligands that inhibit −1 PRF specifically in a broad spectrum of CoVs, establishing frameshift signals as a viable target for developing pan-coronaviral therapeutics.
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40
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Yan S, Zhu Q, Jain S, Schlick T. Length-dependent motions of SARS-CoV-2 frameshifting RNA pseudoknot and alternative conformations suggest avenues for frameshifting suppression. RESEARCH SQUARE 2022:rs.3.rs-1160075. [PMID: 35018371 PMCID: PMC8750709 DOI: 10.21203/rs.3.rs-1160075/v1] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Conserved SARS-CoV-2 RNA regions of critical biological functions define excellent targets for anti-viral therapeutics against Covid-19 variants. One such region is the frameshifting element (FSE), responsible for correct translation of viral polyproteins. Here, we analyze molecular-dynamics motions of three FSE conformations, discovered by graph-theory analysis, and associated mutants designed by graph-based inverse folding: two distinct 3-stem H-type pseudoknots and a 3-way junction. We find that the prevalent H-type pseudoknot in literature adopts ring-like conformations, which in combination with 5' end threading could promote ribosomal pausing. An inherent shape switch from "L" to linear that may help trigger the frameshifting is suppressed in our designed mutant. The alternative conformation trajectories suggest a stable intermediate structure with mixed stem interactions of all three conformations, pointing to a possible transition pathway during ribosomal translation. These observations provide new insights into anti-viral strategies and frameshifting mechanisms.
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Affiliation(s)
- Shuting Yan
- Department of Chemistry, New York University, New York, NY 10003 U.S.A
| | - Qiyao Zhu
- Courant Institute of Mathematical Sciences, New York University, New York, NY 10012 U.S.A
| | - Swati Jain
- Department of Chemistry, New York University, New York, NY 10003 U.S.A
| | - Tamar Schlick
- Department of Chemistry, New York University, New York, NY 10003 U.S.A
- Courant Institute of Mathematical Sciences, New York University, New York, NY 10012 U.S.A
- NYU-ECNU Center for Computational Chemistry, NYU Shanghai, Shanghai 200062, P.R. China
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41
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Zhang Y, Huang K, Xie D, Lau JY, Shen W, Li P, Wang D, Zou Z, Shi S, Ren H, Wang Y, Mao Y, Jin M, Kudla G, Zhao Z. In vivo structure and dynamics of the SARS-CoV-2 RNA genome. Nat Commun 2021; 12:5695. [PMID: 34584097 PMCID: PMC8478942 DOI: 10.1038/s41467-021-25999-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 09/10/2021] [Indexed: 02/08/2023] Open
Abstract
The dynamics of SARS-CoV-2 RNA structure and their functional relevance are largely unknown. Here we develop a simplified SPLASH assay and comprehensively map the in vivo RNA-RNA interactome of SARS-CoV-2 genome across viral life cycle. We report canonical and alternative structures including 5'-UTR and 3'-UTR, frameshifting element (FSE) pseudoknot and genome cyclization in both cells and virions. We provide direct evidence of interactions between Transcription Regulating Sequences, which facilitate discontinuous transcription. In addition, we reveal alternative short and long distance arches around FSE. More importantly, we find that within virions, while SARS-CoV-2 genome RNA undergoes intensive compaction, genome domains remain stable but with strengthened demarcation of local domains and weakened global cyclization. Taken together, our analysis reveals the structural basis for the regulation of replication, discontinuous transcription and translational frameshifting, the alternative conformations and the maintenance of global genome organization during the whole life cycle of SARS-CoV-2, which we anticipate will help develop better antiviral strategies.
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Affiliation(s)
- Yan Zhang
- Beijing institute of Biotechnology, Beijing, China
| | - Kun Huang
- Unit of Animal Infectious Diseases, National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China
| | - Dejian Xie
- Wuhan Frasergen Bioinformatics Co., Ltd, Wuhan, China
| | - Jian You Lau
- MRC Human Genetics Unit, University of Edinburgh, Edinburgh, EH4 2XU, UK
| | - Wenlong Shen
- Beijing institute of Biotechnology, Beijing, China
| | - Ping Li
- Beijing institute of Biotechnology, Beijing, China
| | - Dong Wang
- Department of Microbiology, University of Hong Kong, Queen Mary Hospital, Pokfulam, Hong Kong, China
| | - Zhong Zou
- Unit of Animal Infectious Diseases, National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China
| | - Shu Shi
- Beijing institute of Biotechnology, Beijing, China
| | | | | | - Youzhi Mao
- Wuhan Frasergen Bioinformatics Co., Ltd, Wuhan, China
| | - Meilin Jin
- Unit of Animal Infectious Diseases, National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China.
| | - Grzegorz Kudla
- MRC Human Genetics Unit, University of Edinburgh, Edinburgh, EH4 2XU, UK.
| | - Zhihu Zhao
- Beijing institute of Biotechnology, Beijing, China.
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42
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Bao C, Ermolenko DN. Ribosome as a Translocase and Helicase. BIOCHEMISTRY (MOSCOW) 2021; 86:992-1002. [PMID: 34488575 PMCID: PMC8294220 DOI: 10.1134/s0006297921080095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
During protein synthesis, ribosome moves along mRNA to decode one codon after the other. Ribosome translocation is induced by a universally conserved protein, elongation factor G (EF-G) in bacteria and elongation factor 2 (EF-2) in eukaryotes. EF-G-induced translocation results in unwinding of the intramolecular secondary structures of mRNA by three base pairs at a time that renders the translating ribosome a processive helicase. Professor Alexander Sergeevich Spirin has made numerous seminal contributions to understanding the molecular mechanism of translocation. Here, we review Spirin's insights into the ribosomal translocation and recent advances in the field that stemmed from Spirin's pioneering work. We also discuss key remaining challenges in studies of translocase and helicase activities of the ribosome.
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Affiliation(s)
- Chen Bao
- Department of Biochemistry & Biophysics, School of Medicine and Dentistry and Center for RNA Biology, University of Rochester, Rochester, NY, USA.
| | - Dmitri N Ermolenko
- Department of Biochemistry & Biophysics, School of Medicine and Dentistry and Center for RNA Biology, University of Rochester, Rochester, NY, USA.
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43
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Roman C, Lewicka A, Koirala D, Li NS, Piccirilli JA. The SARS-CoV-2 Programmed -1 Ribosomal Frameshifting Element Crystal Structure Solved to 2.09 Å Using Chaperone-Assisted RNA Crystallography. ACS Chem Biol 2021; 16:1469-1481. [PMID: 34328734 PMCID: PMC8353986 DOI: 10.1021/acschembio.1c00324] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 07/19/2021] [Indexed: 12/12/2022]
Abstract
The programmed -1 ribosomal frameshifting element (PFSE) of SARS-CoV-2 is a well conserved structured RNA found in all coronaviruses' genomes. By adopting a pseudoknot structure in the presence of the ribosome, the PFSE promotes a ribosomal frameshifting event near the stop codon of the first open reading frame Orf1a during translation of the polyprotein pp1a. Frameshifting results in continuation of pp1a via a new open reading frame, Orf1b, that produces the longer pp1ab polyprotein. Polyproteins pp1a and pp1ab produce nonstructural proteins NSPs 1-10 and NSPs 1-16, respectively, which contribute vital functions during the viral life cycle and must be present in the proper stoichiometry. Both drugs and sequence alterations that affect the stability of the -1 programmed ribosomal frameshifting element disrupt the stoichiometry of the NSPs produced, which compromise viral replication. For this reason, the -1 programmed frameshifting element is considered a promising drug target. Using chaperone assisted RNA crystallography, we successfully crystallized and solved the three-dimensional structure of the PFSE. We observe a three-stem H-type pseudoknot structure with the three stems stacked in a vertical orientation stabilized by two triple base pairs at the stem 1/stem 2 and stem 1/stem 3 junctions. This structure provides a new conformation of PFSE distinct from the bent conformations inferred from midresolution cryo-EM models and provides a high-resolution framework for mechanistic investigations and structure-based drug design.
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Affiliation(s)
- Christina Roman
- Department
of Biochemistry and Molecular Biology, The
University of Chicago, Chicago, Illinois 60637, United States
| | - Anna Lewicka
- Department
of Biochemistry and Molecular Biology, The
University of Chicago, Chicago, Illinois 60637, United States
| | - Deepak Koirala
- Department
of Chemistry and Biochemistry, University
of Maryland Baltimore County (UMBC), Baltimore, Maryland 21250, United States
| | - Nan-Sheng Li
- Department
of Biochemistry and Molecular Biology, The
University of Chicago, Chicago, Illinois 60637, United States
| | - Joseph A. Piccirilli
- Department
of Biochemistry and Molecular Biology, The
University of Chicago, Chicago, Illinois 60637, United States
- Department
of Chemistry, The University of Chicago, Chicago, Illinois 60637, United States
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44
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Structural dynamics of single SARS-CoV-2 pseudoknot molecules reveal topologically distinct conformers. Nat Commun 2021; 12:4749. [PMID: 34362921 PMCID: PMC8346527 DOI: 10.1038/s41467-021-25085-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Accepted: 07/21/2021] [Indexed: 11/08/2022] Open
Abstract
The RNA pseudoknot that stimulates programmed ribosomal frameshifting in SARS-CoV-2 is a possible drug target. To understand how it responds to mechanical tension applied by ribosomes, thought to play a key role during frameshifting, we probe its structural dynamics using optical tweezers. We find that it forms multiple structures: two pseudoknotted conformers with different stability and barriers, and alternative stem-loop structures. The pseudoknotted conformers have distinct topologies, one threading the 5′ end through a 3-helix junction to create a knot-like fold, the other with unthreaded 5′ end, consistent with structures observed via cryo-EM and simulations. Refolding of the pseudoknotted conformers starts with stem 1, followed by stem 3 and lastly stem 2; Mg2+ ions are not required, but increase pseudoknot mechanical rigidity and favor formation of the knot-like conformer. These results resolve the SARS-CoV-2 frameshift signal folding mechanism and highlight its conformational heterogeneity, with important implications for structure-based drug-discovery efforts. The RNA pseudoknot of SARS-CoV-2 promotes -1 programmed ribosomal frameshifting. Here the authors use single molecule force spectroscopy to study the folding of this pseudoknot, showing that it forms at least two different pseudoknot conformers with distinct fold topologies.
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45
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Schlick T, Zhu Q, Dey A, Jain S, Yan S, Laederach A. To Knot or Not to Knot: Multiple Conformations of the SARS-CoV-2 Frameshifting RNA Element. J Am Chem Soc 2021; 143:11404-11422. [PMID: 34283611 PMCID: PMC8315264 DOI: 10.1021/jacs.1c03003] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The SARS-CoV-2 frameshifting RNA element (FSE) is an excellent target for therapeutic intervention against Covid-19. This small gene element employs a shifting mechanism to pause and backtrack the ribosome during translation between Open Reading Frames 1a and 1b, which code for viral polyproteins. Any interference with this process has a profound effect on viral replication and propagation. Pinpointing the structures adapted by the FSE and associated structural transformations involved in frameshifting has been a challenge. Using our graph-theory-based modeling tools for representing RNA secondary structures, "RAG" (RNA-As-Graphs), and chemical structure probing experiments, we show that the 3-stem H-type pseudoknot (3_6 dual graph), long assumed to be the dominant structure, has a viable alternative, an HL-type 3-stem pseudoknot (3_3) for longer constructs. In addition, an unknotted 3-way junction RNA (3_5) emerges as a minor conformation. These three conformations share Stems 1 and 3, while the different Stem 2 may be involved in a conformational switch and possibly associations with the ribosome during translation. For full-length genomes, a stem-loop motif (2_2) may compete with these forms. These structural and mechanistic insights advance our understanding of the SARS-CoV-2 frameshifting process and concomitant virus life cycle, and point to three avenues of therapeutic intervention.
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Affiliation(s)
- Tamar Schlick
- Department of Chemistry, New York University, 100 Washington Square East, Silver Building, New York, New York 10003, United States
- Courant Institute of Mathematical Sciences, New York University, 251 Mercer Street, New York, New York 10012, United States
- New York University-East China Normal University Center for Computational Chemistry, New York University-Shanghai, Shanghai 200062, P. R. China
| | - Qiyao Zhu
- Courant Institute of Mathematical Sciences, New York University, 251 Mercer Street, New York, New York 10012, United States
| | - Abhishek Dey
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Swati Jain
- Department of Chemistry, New York University, 100 Washington Square East, Silver Building, New York, New York 10003, United States
| | - Shuting Yan
- Department of Chemistry, New York University, 100 Washington Square East, Silver Building, New York, New York 10003, United States
| | - Alain Laederach
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
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Brant AC, Tian W, Majerciak V, Yang W, Zheng ZM. SARS-CoV-2: from its discovery to genome structure, transcription, and replication. Cell Biosci 2021; 11:136. [PMID: 34281608 PMCID: PMC8287290 DOI: 10.1186/s13578-021-00643-z] [Citation(s) in RCA: 131] [Impact Index Per Article: 43.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 06/30/2021] [Indexed: 02/08/2023] Open
Abstract
SARS-CoV-2 is an extremely contagious respiratory virus causing adult atypical pneumonia COVID-19 with severe acute respiratory syndrome (SARS). SARS-CoV-2 has a single-stranded, positive-sense RNA (+RNA) genome of ~ 29.9 kb and exhibits significant genetic shift from different isolates. After entering the susceptible cells expressing both ACE2 and TMPRSS2, the SARS-CoV-2 genome directly functions as an mRNA to translate two polyproteins from the ORF1a and ORF1b region, which are cleaved by two viral proteases into sixteen non-structural proteins (nsp1-16) to initiate viral genome replication and transcription. The SARS-CoV-2 genome also encodes four structural (S, E, M and N) and up to six accessory (3a, 6, 7a, 7b, 8, and 9b) proteins, but their translation requires newly synthesized individual subgenomic RNAs (sgRNA) in the infected cells. Synthesis of the full-length viral genomic RNA (gRNA) and sgRNAs are conducted inside double-membrane vesicles (DMVs) by the viral replication and transcription complex (RTC), which comprises nsp7, nsp8, nsp9, nsp12, nsp13 and a short RNA primer. To produce sgRNAs, RTC starts RNA synthesis from the highly structured gRNA 3' end and switches template at various transcription regulatory sequence (TRSB) sites along the gRNA body probably mediated by a long-distance RNA-RNA interaction. The TRS motif in the gRNA 5' leader (TRSL) is responsible for the RNA-RNA interaction with the TRSB upstream of each ORF and skipping of the viral genome in between them to produce individual sgRNAs. Abundance of individual sgRNAs and viral gRNA synthesized in the infected cells depend on the location and read-through efficiency of each TRSB. Although more studies are needed, the unprecedented COVID-19 pandemic has taught the world a painful lesson that is to invest and proactively prepare future emergence of other types of coronaviruses and any other possible biological horrors.
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Affiliation(s)
- Ayslan Castro Brant
- Tumor Virus RNA Biology Section, HIV DRP, National Cancer Institute, NIH, Frederick, MD, USA
| | - Wei Tian
- Mechanism of DNA Repair, Replication, and Recombination Section, Laboratory of Molecular Biology, NIDDK, Bethesda, MD, USA
| | - Vladimir Majerciak
- Tumor Virus RNA Biology Section, HIV DRP, National Cancer Institute, NIH, Frederick, MD, USA
| | - Wei Yang
- Mechanism of DNA Repair, Replication, and Recombination Section, Laboratory of Molecular Biology, NIDDK, Bethesda, MD, USA.
| | - Zhi-Ming Zheng
- Tumor Virus RNA Biology Section, HIV DRP, National Cancer Institute, NIH, Frederick, MD, USA.
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Schlick T, Zhu Q, Dey A, Jain S, Yan S, Laederach A. To knot or not to knot: Multiple conformations of the SARS-CoV-2 frameshifting RNA element. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2021:2021.03.31.437955. [PMID: 33821274 PMCID: PMC8020974 DOI: 10.1101/2021.03.31.437955] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The SARS-CoV-2 frameshifting RNA element (FSE) is an excellent target for therapeutic intervention against Covid-19. This small gene element employs a shifting mechanism to pause and backtrack the ribosome during translation between Open Reading Frames 1a and 1b, which code for viral polyproteins. Any interference with this process has profound effect on viral replication and propagation. Pinpointing the structures adapted by the FSE and associated structural transformations involved in frameshifting has been a challenge. Using our graph-theory-based modeling tools for representing RNA secondary structures, "RAG" (RNA-As-Graphs), and chemical structure probing experiments, we show that the 3-stem H-type pseudoknot (3_6 dual graph), long assumed to be the dominant structure has a viable alternative, an HL-type 3-stem pseudoknot (3_3) for longer constructs. In addition, an unknotted 3-way junction RNA (3_5) emerges as a minor conformation. These three conformations share Stems 1 and 3, while the different Stem 2 may be involved in a conformational switch and possibly associations with the ribosome during translation. For full-length genomes, a stem-loop motif (2_2) may compete with these forms. These structural and mechanistic insights advance our understanding of the SARS-CoV-2 frameshifting process and concomitant virus life cycle, and point to three avenues of therapeutic intervention.
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Affiliation(s)
- Tamar Schlick
- Department of Chemistry, 100 Washington Square East, Silver Building, New York University, New York, NY 10003 U.S.A
- Courant Institute of Mathematical Sciences, New York University, 251 Mercer St., New York, NY 10012 U.S.A
- NYU-ECNU Center for Computational Chemistry, NYU Shanghai, Shanghai 200062, P.R. China
| | - Qiyao Zhu
- Courant Institute of Mathematical Sciences, New York University, 251 Mercer St., New York, NY 10012 U.S.A
| | - Abhishek Dey
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Swati Jain
- Department of Chemistry, 100 Washington Square East, Silver Building, New York University, New York, NY 10003 U.S.A
| | - Shuting Yan
- Department of Chemistry, 100 Washington Square East, Silver Building, New York University, New York, NY 10003 U.S.A
| | - Alain Laederach
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
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Chang KC, Wen JD. Programmed -1 ribosomal frameshifting from the perspective of the conformational dynamics of mRNA and ribosomes. Comput Struct Biotechnol J 2021; 19:3580-3588. [PMID: 34257837 PMCID: PMC8246090 DOI: 10.1016/j.csbj.2021.06.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 06/11/2021] [Accepted: 06/12/2021] [Indexed: 11/01/2022] Open
Abstract
Programmed -1 ribosomal frameshifting (-1 PRF) is a translation mechanism that regulates the relative expression level of two proteins encoded on the same messenger RNA (mRNA). This regulation is commonly used by viruses such as coronaviruses and retroviruses but rarely by host human cells, and for this reason, it has long been considered as a therapeutic target for antiviral drug development. Understanding the molecular mechanism of -1 PRF is one step toward this goal. Minus-one PRF occurs with a certain efficiency when translating ribosomes encounter the specialized mRNA signal consisting of the frameshifting site and a downstream stimulatory structure, which impedes translocation of the ribosome. The impeded ribosome can still undergo profound conformational changes to proceed with translocation; however, some of these changes may be unique and essential to frameshifting. In addition, most stimulatory structures exhibit conformational dynamics and sufficient mechanical strength, which, when under the action of ribosomes, may in turn further promote -1 PRF efficiency. In this review, we discuss how the dynamic features of ribosomes and mRNA stimulatory structures may influence the occurrence of -1 PRF and propose a hypothetical frameshifting model that recapitulates the role of conformational dynamics.
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Affiliation(s)
- Kai-Chun Chang
- Department of Bioengineering and Therapeutic Sciences, Schools of Medicine and Pharmacy, University of California, San Francisco, CA 94158, United States
| | - Jin-Der Wen
- Institute of Molecular and Cellular Biology, National Taiwan University, Taipei 10617, Taiwan
- Genome and Systems Biology Degree Program, National Taiwan University and Academia Sinica, Taipei 10617, Taiwan
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