1
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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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2
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Grigoreva TA, Vorona SV, Novikova DS, Tribulovich VG. Rational Design Problematics of Peptide Nucleic Acids as SARS-CoV-2 Inhibitors. ACS OMEGA 2024; 9:33000-33010. [PMID: 39100288 PMCID: PMC11292644 DOI: 10.1021/acsomega.4c04023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2024] [Revised: 06/24/2024] [Accepted: 07/05/2024] [Indexed: 08/06/2024]
Abstract
The use of viral protein inhibitors has shown to be insufficiently effective in the case of highly variable SARS-CoV-2. In this work, we examined the possibility of designing agents that bind to a highly conserved region of coronavirus (+)RNA. We demonstrated that while the design of antisense RNAs is based on the complementary interaction of nitrogenous bases, it is possible to use semirigid docking methods in the case of unnatural peptide nucleic acids. The transition from N-(2-aminoethyl)glycine chain to a more conformationally rigid piperidine-containing backbone allowed us to significantly increase the affinity of structures to the target RNA.
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Affiliation(s)
- Tatyana A. Grigoreva
- Laboratory of Molecular
Pharmacology, St. Petersburg State Institute of Technology (Technical
University), Moskovskii pr., 26, St. Petersburg 190013, Russia
| | - Svetlana V. Vorona
- Laboratory of Molecular
Pharmacology, St. Petersburg State Institute of Technology (Technical
University), Moskovskii pr., 26, St. Petersburg 190013, Russia
| | - Daria S. Novikova
- Laboratory of Molecular
Pharmacology, St. Petersburg State Institute of Technology (Technical
University), Moskovskii pr., 26, St. Petersburg 190013, Russia
| | - Vyacheslav G. Tribulovich
- Laboratory of Molecular
Pharmacology, St. Petersburg State Institute of Technology (Technical
University), Moskovskii pr., 26, St. Petersburg 190013, Russia
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3
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Nazir F, John Kombe Kombe A, Khalid Z, Bibi S, Zhang H, Wu S, Jin T. SARS-CoV-2 replication and drug discovery. Mol Cell Probes 2024; 77:101973. [PMID: 39025272 DOI: 10.1016/j.mcp.2024.101973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 07/14/2024] [Accepted: 07/15/2024] [Indexed: 07/20/2024]
Abstract
The coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has killed millions of people and continues to wreak havoc across the globe. This sudden and deadly pandemic emphasizes the necessity for anti-viral drug development that can be rapidly administered to reduce morbidity, mortality, and virus propagation. Thus, lacking efficient anti-COVID-19 treatment, and especially given the lengthy drug development process as well as the critical death tool that has been associated with SARS-CoV-2 since its outbreak, drug repurposing (or repositioning) constitutes so far, the ideal and ready-to-go best approach in mitigating viral spread, containing the infection, and reducing the COVID-19-associated death rate. Indeed, based on the molecular similarity approach of SARS-CoV-2 with previous coronaviruses (CoVs), repurposed drugs have been reported to hamper SARS-CoV-2 replication. Therefore, understanding the inhibition mechanisms of viral replication by repurposed anti-viral drugs and chemicals known to block CoV and SARS-CoV-2 multiplication is crucial, and it opens the way for particular treatment options and COVID-19 therapeutics. In this review, we highlighted molecular basics underlying drug-repurposing strategies against SARS-CoV-2. Notably, we discussed inhibition mechanisms of viral replication, involving and including inhibition of SARS-CoV-2 proteases (3C-like protease, 3CLpro or Papain-like protease, PLpro) by protease inhibitors such as Carmofur, Ebselen, and GRL017, polymerases (RNA-dependent RNA-polymerase, RdRp) by drugs like Suramin, Remdesivir, or Favipiravir, and proteins/peptides inhibiting virus-cell fusion and host cell replication pathways, such as Disulfiram, GC376, and Molnupiravir. When applicable, comparisons with SARS-CoV inhibitors approved for clinical use were made to provide further insights to understand molecular basics in inhibiting SARS-CoV-2 replication and draw conclusions for future drug discovery research.
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Affiliation(s)
- Farah Nazir
- Center of Disease Immunity and Investigation, College of Medicine, Lishui University, Lishui, 323000, China
| | - Arnaud John Kombe Kombe
- Laboratory of Structural Immunology, Key Laboratory of Immune Response and Immunotherapy, School of Basic Medical Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, China
| | - Zunera Khalid
- Laboratory of Structural Immunology, Key Laboratory of Immune Response and Immunotherapy, School of Basic Medical Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, China
| | - Shaheen Bibi
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, University of Science and Technology of China, Anhui, China
| | - Hongliang Zhang
- Center of Disease Immunity and Investigation, College of Medicine, Lishui University, Lishui, 323000, China
| | - Songquan Wu
- Center of Disease Immunity and Investigation, College of Medicine, Lishui University, Lishui, 323000, China.
| | - Tengchuan Jin
- Center of Disease Immunity and Investigation, College of Medicine, Lishui University, Lishui, 323000, China; Laboratory of Structural Immunology, Key Laboratory of Immune Response and Immunotherapy, School of Basic Medical Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, China; Department of Obstetrics and Gynecology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, University of Science and Technology of China, Anhui, China; Institute of Health and Medicine, Hefei Comprehensive National Science Center, Hefei, Anhui, China; Biomedical Sciences and Health Laboratory of Anhui Province, University of Science & Technology of China, Hefei, 230027, China; Clinical Research Hospital of Chinese Academy of Sciences (Hefei), University of Science and Technology of China, Hefei, 230001, China.
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4
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Nithin C, Kmiecik S, Błaszczyk R, Nowicka J, Tuszyńska I. Comparative analysis of RNA 3D structure prediction methods: towards enhanced modeling of RNA-ligand interactions. Nucleic Acids Res 2024; 52:7465-7486. [PMID: 38917327 PMCID: PMC11260495 DOI: 10.1093/nar/gkae541] [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: 04/04/2024] [Revised: 05/23/2024] [Accepted: 06/16/2024] [Indexed: 06/27/2024] Open
Abstract
Accurate RNA structure models are crucial for designing small molecule ligands that modulate their functions. This study assesses six standalone RNA 3D structure prediction methods-DeepFoldRNA, RhoFold, BRiQ, FARFAR2, SimRNA and Vfold2, excluding web-based tools due to intellectual property concerns. We focus on reproducing the RNA structure existing in RNA-small molecule complexes, particularly on the ability to model ligand binding sites. Using a comprehensive set of RNA structures from the PDB, which includes diverse structural elements, we found that machine learning (ML)-based methods effectively predict global RNA folds but are less accurate with local interactions. Conversely, non-ML-based methods demonstrate higher precision in modeling intramolecular interactions, particularly with secondary structure restraints. Importantly, ligand-binding site accuracy can remain sufficiently high for practical use, even if the overall model quality is not optimal. With the recent release of AlphaFold 3, we included this advanced method in our tests. Benchmark subsets containing new structures, not used in the training of the tested ML methods, show that AlphaFold 3's performance was comparable to other ML-based methods, albeit with some challenges in accurately modeling ligand binding sites. This study underscores the importance of enhancing binding site prediction accuracy and the challenges in modeling RNA-ligand interactions accurately.
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Affiliation(s)
- Chandran Nithin
- Molecure SA, 02-089 Warsaw, Poland
- Laboratory of Computational Biology, Biological and Chemical Research Center, Faculty of Chemistry, University of Warsaw, 02-089 Warsaw, Poland
| | - Sebastian Kmiecik
- Laboratory of Computational Biology, Biological and Chemical Research Center, Faculty of Chemistry, University of Warsaw, 02-089 Warsaw, Poland
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5
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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. [PMID: 39037082 DOI: 10.1021/acs.jcim.4c00758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [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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6
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Scholten NR, Haandrikman D, Tolhuis JO, Morandi E, Incarnato D. SHAPEwarp-web: sequence-agnostic search for structurally homologous RNA regions across databases of chemical probing data. Nucleic Acids Res 2024; 52:W362-W367. [PMID: 38709889 PMCID: PMC11223795 DOI: 10.1093/nar/gkae348] [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: 03/18/2024] [Revised: 04/08/2024] [Accepted: 04/19/2024] [Indexed: 05/08/2024] Open
Abstract
RNA molecules perform a variety of functions in cells, many of which rely on their secondary and tertiary structures. Chemical probing methods coupled with high-throughput sequencing have significantly accelerated the mapping of RNA structures, and increasingly large datasets of transcriptome-wide RNA chemical probing data are becoming available. Analogously to what has been done for decades in the protein world, this RNA structural information can be leveraged to aid the discovery of structural similarity to a known RNA (or RNA family), which, in turn, can inform about the function of transcripts. We have previously developed SHAPEwarp, a sequence-agnostic method for the search of structurally homologous RNA segments in a database of reactivity profiles derived from chemical probing experiments. In its original implementation, however, SHAPEwarp required substantial computational resources, even for moderately sized databases, as well as significant Linux command line know-how. To address these limitations, we introduce here SHAPEwarp-web, a user-friendly web interface to rapidly query large databases of RNA chemical probing data for structurally similar RNAs. Aside from featuring a completely rewritten core, which speeds up by orders of magnitude the search inside large databases, the web server hosts several high-quality chemical probing databases across multiple species. SHAPEwarp-web is available from https://shapewarp.incarnatolab.com.
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Affiliation(s)
- Niek R Scholten
- School for Life Science and Technology, Hanze University of Applied Sciences, 9747 AS Groningen, The Netherlands
| | - Dennis Haandrikman
- School for Life Science and Technology, Hanze University of Applied Sciences, 9747 AS Groningen, The Netherlands
| | - Joshua O Tolhuis
- School for Life Science and Technology, Hanze University of Applied Sciences, 9747 AS Groningen, The Netherlands
| | - Edoardo Morandi
- Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, 9747 AG Groningen, The Netherlands
| | - Danny Incarnato
- Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, 9747 AG Groningen, The Netherlands
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7
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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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8
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Rouse WB, Tompkins VS, O’Leary CA, Moss WN. The RNA secondary structure of androgen receptor-FL and V7 transcripts reveals novel regulatory regions. Nucleic Acids Res 2024; 52:6596-6613. [PMID: 38554103 PMCID: PMC11194067 DOI: 10.1093/nar/gkae220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Accepted: 03/18/2024] [Indexed: 04/01/2024] Open
Abstract
The androgen receptor (AR) is a ligand-dependent nuclear transcription factor belonging to the steroid hormone nuclear receptor family. Due to its roles in regulating cell proliferation and differentiation, AR is tightly regulated to maintain proper levels of itself and the many genes it controls. AR dysregulation is a driver of many human diseases including prostate cancer. Though this dysregulation often occurs at the RNA level, there are many unknowns surrounding post-transcriptional regulation of AR mRNA, particularly the role that RNA secondary structure plays. Thus, a comprehensive analysis of AR transcript secondary structure is needed. We address this through the computational and experimental analyses of two key isoforms, full length (AR-FL) and truncated (AR-V7). Here, a combination of in-cell RNA secondary structure probing experiments (targeted DMS-MaPseq) and computational predictions were used to characterize the static structural landscape and conformational dynamics of both isoforms. Additionally, in-cell assays were used to identify functionally relevant structures in the 5' and 3' UTRs of AR-FL. A notable example is a conserved stem loop structure in the 5'UTR of AR-FL that can bind to Poly(RC) Binding Protein 2 (PCBP2). Taken together, our results reveal novel features that regulate AR expression.
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Affiliation(s)
- Warren B Rouse
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA 50011, USA
| | - Van S Tompkins
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA 50011, USA
| | - Collin A O’Leary
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA 50011, USA
- Current Address: Departments of Biology and Chemistry, Cornell College, Mount Vernon, IA 52314, USA
| | - Walter N Moss
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA 50011, USA
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9
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Matzel T, Martin MW, Herr A, Wacker A, Richter C, Sreeramulu S, Schwalbe H. NMR characterization and ligand binding site of the stem-loop 2 motif from the Delta variant of SARS-CoV-2. RNA (NEW YORK, N.Y.) 2024; 30:779-794. [PMID: 38565242 PMCID: PMC11182009 DOI: 10.1261/rna.079902.123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Accepted: 03/08/2024] [Indexed: 04/04/2024]
Abstract
The stem-loop 2 motif (s2m) in SARS-CoV-2 (SCoV-2) is located in the 3'-UTR. Although s2m has been reported to display characteristics of a mobile genomic element that might lead to an evolutionary advantage, its function has remained unknown. The secondary structure of the original SCoV-2 RNA sequence (Wuhan-Hu-1) was determined by NMR in late 2020, delineating the base-pairing pattern and revealing substantial differences in secondary structure compared to SARS-CoV-1 (SCoV-1). The existence of a single G29742-A29756 mismatch in the upper stem of s2m leads to its destabilization and impedes a complete NMR analysis. With Delta, a variant of concern has evolved with one mutation compared to the original sequence that replaces G29742 by U29742. We show here that this mutation results in a more defined structure at ambient temperature accompanied by a rise in melting temperature. Consequently, we were able to identify >90% of the relevant NMR resonances using a combination of selective RNA labeling and filtered 2D NOESY as well as 4D NMR experiments. We present a comprehensive NMR analysis of the secondary structure, (sub)nanosecond dynamics, and ribose conformation of s2m Delta based on heteronuclear 13C NOE and T 1 measurements and ribose carbon chemical shift-derived canonical coordinates. We further show that the G29742U mutation in Delta has no influence on the druggability of s2m compared to the Wuhan-Hu-1 sequence. With the assignment at hand, we identify the flexible regions of s2m as the primary site for small molecule binding.
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Affiliation(s)
- Tobias Matzel
- Institute for Organic Chemistry and Chemical Biology, Center for Biomolecular Magnetic Resonance (BMRZ), Goethe-Universität Frankfurt, 60438 Frankfurt, Germany
| | - Maria Wirtz Martin
- Institute for Organic Chemistry and Chemical Biology, Center for Biomolecular Magnetic Resonance (BMRZ), Goethe-Universität Frankfurt, 60438 Frankfurt, Germany
| | - Alexander Herr
- Institute for Organic Chemistry and Chemical Biology, Center for Biomolecular Magnetic Resonance (BMRZ), Goethe-Universität Frankfurt, 60438 Frankfurt, Germany
| | - Anna Wacker
- Institute for Organic Chemistry and Chemical Biology, Center for Biomolecular Magnetic Resonance (BMRZ), Goethe-Universität Frankfurt, 60438 Frankfurt, Germany
| | - Christian Richter
- Institute for Organic Chemistry and Chemical Biology, Center for Biomolecular Magnetic Resonance (BMRZ), Goethe-Universität Frankfurt, 60438 Frankfurt, Germany
| | - Sridhar Sreeramulu
- Institute for Organic Chemistry and Chemical Biology, Center for Biomolecular Magnetic Resonance (BMRZ), Goethe-Universität Frankfurt, 60438 Frankfurt, Germany
| | - Harald Schwalbe
- Institute for Organic Chemistry and Chemical Biology, Center for Biomolecular Magnetic Resonance (BMRZ), Goethe-Universität Frankfurt, 60438 Frankfurt, Germany
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10
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Andrzejewska-Romanowska A, Gumna J, Tykwińska E, Pachulska-Wieczorek K. Mapping the structural landscape of the yeast Ty3 retrotransposon RNA genome. Nucleic Acids Res 2024:gkae494. [PMID: 38864374 DOI: 10.1093/nar/gkae494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 04/30/2024] [Accepted: 05/29/2024] [Indexed: 06/13/2024] Open
Abstract
Long terminal repeat (LTR)-retrotransposons are significant contributors to the evolution and diversity of eukaryotic genomes. Their RNA genomes (gRNA) serve as a template for protein synthesis and reverse transcription to a DNA copy, which can integrate into the host genome. Here, we used the SHAPE-MaP strategy to explore Ty3 retrotransposon gRNA structure in yeast and under cell-free conditions. Our study reveals the structural dynamics of Ty3 gRNA and the well-folded core, formed independently of the cellular environment. Based on the detailed map of Ty3 gRNA structure, we characterized the structural context of cis-acting sequences involved in reverse transcription and frameshifting. We also identified a novel functional sequence as a potential initiator for Ty3 gRNA dimerization. Our data indicate that the dimer is maintained by direct interaction between short palindromic sequences at the 5' ends of the two Ty3 gRNAs, resembling the model characteristic for other retroelements like HIV-1 and Ty1. This work points out a range of cell-dependent and -independent Ty3 gRNA structural changes that provide a solid background for studies on RNA structure-function relationships important for retroelement biology.
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Affiliation(s)
- Angelika Andrzejewska-Romanowska
- Department of RNA Structure and Function, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland
| | - Julita Gumna
- Department of RNA Structure and Function, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland
| | - Ewa Tykwińska
- Department of RNA Structure and Function, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland
| | - Katarzyna Pachulska-Wieczorek
- Department of RNA Structure and Function, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland
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11
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Peterson JM, Becker ST, O'Leary CA, Juneja P, Yang Y, Moss WN. Structure of the SARS-CoV-2 Frameshift Stimulatory Element with an Upstream Multibranch Loop. Biochemistry 2024; 63:1287-1296. [PMID: 38727003 DOI: 10.1021/acs.biochem.3c00716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) frameshift stimulatory element (FSE) is necessary for programmed -1 ribosomal frameshifting (-1 PRF) and optimized viral efficacy. The FSE has an abundance of context-dependent alternate conformations, but two of the structures most crucial to -1 PRF are an attenuator hairpin and a three-stem H-type pseudoknot structure. A crystal structure of the pseudoknot alone features three RNA stems in a helically stacked linear structure, whereas a 6.9 Å cryo-EM structure including the upstream heptameric slippery site resulted in a bend between two stems. Our previous research alluded to an extended upstream multibranch loop that includes both the attenuator hairpin and the slippery site-a conformation not previously modeled. We aim to provide further context to the SARS-CoV-2 FSE via computational and medium resolution cryo-EM approaches, by presenting a 6.1 Å cryo-EM structure featuring a linear pseudoknot structure and a dynamic upstream multibranch loop.
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Affiliation(s)
- Jake M Peterson
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa 50011, United States
| | - Scott T Becker
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa 50011, United States
| | - Collin A O'Leary
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa 50011, United States
| | - Puneet Juneja
- Cryo-EM Facility, Iowa State University, Ames, Iowa 50011, United States
| | - Yang Yang
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa 50011, United States
| | - Walter N Moss
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa 50011, United States
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12
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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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13
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Nagasawa R, Onizuka K, Komatsu KR, Miyashita E, Murase H, Ojima K, Ishikawa S, Ozawa M, Saito H, Nagatsugi F. Large-scale analysis of small molecule-RNA interactions using multiplexed RNA structure libraries. Commun Chem 2024; 7:98. [PMID: 38693284 DOI: 10.1038/s42004-024-01181-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 04/17/2024] [Indexed: 05/03/2024] Open
Abstract
The large-scale analysis of small-molecule binding to diverse RNA structures is key to understanding the required interaction properties and selectivity for developing RNA-binding molecules toward RNA-targeted therapies. Here, we report a new system for performing the large-scale analysis of small molecule-RNA interactions using a multiplexed pull-down assay with RNA structure libraries. The system profiled the RNA-binding landscapes of G-clamp and thiazole orange derivatives, which recognizes an unpaired guanine base and are good probes for fluorescent indicator displacement (FID) assays, respectively. We discuss the binding preferences of these molecules based on their large-scale affinity profiles. In addition, we selected combinations of fluorescent indicators and different ranks of RNA based on the information and screened for RNA-binding molecules using FID. RNAs with high- and intermediate-rank RNA provided reliable results. Our system provides fundamental information about small molecule-RNA interactions and facilitates the discovery of novel RNA-binding molecules.
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Affiliation(s)
- Ryosuke Nagasawa
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Miyagi, 980-8577, Japan
- Department of Chemistry, Graduate School of Science, Tohoku University, Miyagi, 980-8578, Japan
| | - Kazumitsu Onizuka
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Miyagi, 980-8577, Japan.
- Department of Chemistry, Graduate School of Science, Tohoku University, Miyagi, 980-8578, Japan.
- Division for the Establishment of Frontier Sciences of Organization for Advanced Studies, Tohoku University, Miyagi, 980-8577, Japan.
| | - Kaoru R Komatsu
- Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto, 606-8507, Japan
| | - Emi Miyashita
- Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto, 606-8507, Japan
| | - Hirotaka Murase
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Miyagi, 980-8577, Japan
| | - Kanna Ojima
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Miyagi, 980-8577, Japan
- Department of Chemistry, Graduate School of Science, Tohoku University, Miyagi, 980-8578, Japan
| | - Shunya Ishikawa
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Miyagi, 980-8577, Japan
- Department of Chemistry, Graduate School of Science, Tohoku University, Miyagi, 980-8578, Japan
| | - Mamiko Ozawa
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Miyagi, 980-8577, Japan
| | - Hirohide Saito
- Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto, 606-8507, Japan.
| | - Fumi Nagatsugi
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Miyagi, 980-8577, Japan.
- Department of Chemistry, Graduate School of Science, Tohoku University, Miyagi, 980-8578, Japan.
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14
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Ohyama T, Osawa T, Sekine SI, Ishii Y. NMR Studies of Genomic RNA in 3' Untranslated Region Unveil Pseudoknot Structure that Initiates Viral RNA Replication in SARS-CoV-2. JACS AU 2024; 4:1323-1333. [PMID: 38665648 PMCID: PMC11041675 DOI: 10.1021/jacsau.3c00641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 02/20/2024] [Accepted: 03/08/2024] [Indexed: 04/28/2024]
Abstract
In the 3' untranslated region of the SARS-CoV-2 virus RNA genome, genomic RNA replication is initiated in the highly conserved region called 3'PK, containing three stem structures (P1pk, P2, and P5). According to one proposed mechanism, P1pk and distal P2 stems switch their structure to a pseudoknot through base-pairing, thereby initiating transcription by recruiting RNA-dependent RNA polymerase complexed with nonstructural proteins (nsp)7 and nsp8. However, experimental evidence of pseudoknot formation or structural switching is unavailable. Using SARS-CoV-2 3'PK fragments, we show that 3'PK adopted stem-loop and pseudoknot forms in a mutually exclusive manner. When P1pk and P2 formed a pseudoknot, the P5 stem, which includes a sequence at the 3' end, exited from the stem-loop structure and opened up. Interaction with the nsp7/nsp8 complex destabilized the stem-loop form but did not alter the pseudoknot form. These results suggest that the interaction between the pseudoknot and nsp7/nsp8 complex transformed the 3' end of viral genomic RNA into single-stranded RNA ready for synthesis, presenting the unique pseudoknot structure as a potential pharmacological target.
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Affiliation(s)
- Takako Ohyama
- Laboratory for Advanced NMR Application and
Development, Center for Biosystems Dynamics Research, RIKEN,
1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Kanagawa,
Japan
- School of Life Science and Technology,
Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku,
Yokohama 226-8503, Kanagawa, Japan
| | - Takuo Osawa
- Laboratory for Transcription Structural Biology,
Center for Biosystems Dynamics Research, RIKEN, 1-7-22
Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Kanagawa, Japan
| | - Shun-ichi Sekine
- Laboratory for Transcription Structural Biology,
Center for Biosystems Dynamics Research, RIKEN, 1-7-22
Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Kanagawa, Japan
| | - Yoshitaka Ishii
- Laboratory for Advanced NMR Application and
Development, Center for Biosystems Dynamics Research, RIKEN,
1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Kanagawa,
Japan
- School of Life Science and Technology,
Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku,
Yokohama 226-8503, Kanagawa, Japan
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15
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Liu G, Jiang H, Chen D, Murchie AIH. Identification of Hammerhead-variant ribozyme sequences in SARS-CoV-2. Nucleic Acids Res 2024; 52:3262-3277. [PMID: 38296822 PMCID: PMC11014351 DOI: 10.1093/nar/gkae037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 01/06/2024] [Accepted: 01/11/2024] [Indexed: 02/02/2024] Open
Abstract
The SARS-CoV-2 RNA virus and variants, responsible for the COVID-19 pandemic has become endemic, raised a need for further understanding of the viral genome and biology. Despite vast research on SARS-CoV-2, no ribozymes have been found in the virus genome. Here we report the identification of 39 Hammerhead-variant ribozyme sequences (CoV-HHRz) in SARS-CoV-2. These sequences are highly conserved within SARS-CoV-2 variants but show large diversity among other coronaviruses. In vitro CoV-HHRz sequences possess the characteristics of typical ribozymes; cleavage is pH and ion dependent, although their activity is relatively low and Mn2+ is required for cleavage. The cleavage sites of four CoV-HHRz coincide with the breakpoint of expressed subgenomic RNA (sgRNAs) in SARS-CoV-2 transcriptome data suggesting in vivo activity. The CoV-HHRz are involved in processing sgRNAs for ORF7b, ORF 10 and ORF1ab nsp13 which are essential for viral packaging and life cycle.
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Affiliation(s)
- Getong Liu
- Shanghai Pudong Hospital, Fudan University Pudong Medical Center and Institutes of Biomedical Sciences, Shanghai Medical College, Key Laboratory of Medical Epigenetics and Metabolism, Fudan University, Shanghai 200032, China
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Hengyi Jiang
- Shanghai Pudong Hospital, Fudan University Pudong Medical Center and Institutes of Biomedical Sciences, Shanghai Medical College, Key Laboratory of Medical Epigenetics and Metabolism, Fudan University, Shanghai 200032, China
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Dongrong Chen
- Shanghai Pudong Hospital, Fudan University Pudong Medical Center and Institutes of Biomedical Sciences, Shanghai Medical College, Key Laboratory of Medical Epigenetics and Metabolism, Fudan University, Shanghai 200032, China
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Alastair I H Murchie
- Shanghai Pudong Hospital, Fudan University Pudong Medical Center and Institutes of Biomedical Sciences, Shanghai Medical College, Key Laboratory of Medical Epigenetics and Metabolism, Fudan University, Shanghai 200032, China
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
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16
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de Moura TR, Purta E, Bernat A, Martín-Cuevas E, Kurkowska M, Baulin E, Mukherjee S, Nowak J, Biela A, Rawski M, Glatt S, Moreno-Herrero F, Bujnicki J. Conserved structures and dynamics in 5'-proximal regions of Betacoronavirus RNA genomes. Nucleic Acids Res 2024; 52:3419-3432. [PMID: 38426934 PMCID: PMC11014237 DOI: 10.1093/nar/gkae144] [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: 10/09/2023] [Revised: 01/25/2024] [Accepted: 02/26/2024] [Indexed: 03/02/2024] Open
Abstract
Betacoronaviruses are a genus within the Coronaviridae family of RNA viruses. They are capable of infecting vertebrates and causing epidemics as well as global pandemics in humans. Mitigating the threat posed by Betacoronaviruses requires an understanding of their molecular diversity. The development of novel antivirals hinges on understanding the key regulatory elements within the viral RNA genomes, in particular the 5'-proximal region, which is pivotal for viral protein synthesis. Using a combination of cryo-electron microscopy, atomic force microscopy, chemical probing, and computational modeling, we determined the structures of 5'-proximal regions in RNA genomes of Betacoronaviruses from four subgenera: OC43-CoV, SARS-CoV-2, MERS-CoV, and Rousettus bat-CoV. We obtained cryo-electron microscopy maps and determined atomic-resolution models for the stem-loop-5 (SL5) region at the translation start site and found that despite low sequence similarity and variable length of the helical elements it exhibits a remarkable structural conservation. Atomic force microscopy imaging revealed a common domain organization and a dynamic arrangement of structural elements connected with flexible linkers across all four Betacoronavirus subgenera. Together, these results reveal common features of a critical regulatory region shared between different Betacoronavirus RNA genomes, which may allow targeting of these RNAs by broad-spectrum antiviral therapeutics.
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Affiliation(s)
- Tales Rocha de Moura
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, ul. Ks. Trojdena 4, 02-109 Warsaw, Poland
| | - Elżbieta Purta
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, ul. Ks. Trojdena 4, 02-109 Warsaw, Poland
| | - Agata Bernat
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, ul. Ks. Trojdena 4, 02-109 Warsaw, Poland
| | - Eva M Martín-Cuevas
- Department of Macromolecular Structures, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Małgorzata Kurkowska
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, ul. Ks. Trojdena 4, 02-109 Warsaw, Poland
| | - Eugene F Baulin
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, ul. Ks. Trojdena 4, 02-109 Warsaw, Poland
| | - Sunandan Mukherjee
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, ul. Ks. Trojdena 4, 02-109 Warsaw, Poland
| | - Jakub Nowak
- Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland
| | - Artur P Biela
- Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland
| | - Michał Rawski
- Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland
- National Synchrotron Radiation Centre SOLARIS, Jagiellonian University, Krakow, Poland
| | - Sebastian Glatt
- Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland
| | - Fernando Moreno-Herrero
- Department of Macromolecular Structures, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Janusz M Bujnicki
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, ul. Ks. Trojdena 4, 02-109 Warsaw, Poland
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17
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Ziesel A, Jabbari H. Unveiling hidden structural patterns in the SARS-CoV-2 genome: Computational insights and comparative analysis. PLoS One 2024; 19:e0298164. [PMID: 38574063 PMCID: PMC10994416 DOI: 10.1371/journal.pone.0298164] [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: 10/06/2023] [Accepted: 01/19/2024] [Indexed: 04/06/2024] Open
Abstract
SARS-CoV-2, the causative agent of COVID-19, is known to exhibit secondary structures in its 5' and 3' untranslated regions, along with the frameshifting stimulatory element situated between ORF1a and 1b. To identify additional regions containing conserved structures, we utilized a multiple sequence alignment with related coronaviruses as a starting point. We applied a computational pipeline developed for identifying non-coding RNA elements. Our pipeline employed three different RNA structural prediction approaches. We identified forty genomic regions likely to harbor structures, with ten of them showing three-way consensus substructure predictions among our predictive utilities. We conducted intracomparisons of the predictive utilities within the pipeline and intercomparisons with four previously published SARS-CoV-2 structural datasets. While there was limited agreement on the precise structure, different approaches seemed to converge on regions likely to contain structures in the viral genome. By comparing and combining various computational approaches, we can predict regions most likely to form structures, as well as a probable structure or ensemble of structures. These predictions can be used to guide surveillance, prophylactic measures, or therapeutic efforts. Data and scripts employed in this study may be found at https://doi.org/10.5281/zenodo.8298680.
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Affiliation(s)
- Alison Ziesel
- Department of Biomedical Engineering, University of Alberta, Edmonton, Alberta, Canada
| | - Hosna Jabbari
- Department of Biomedical Engineering, University of Alberta, Edmonton, Alberta, Canada
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18
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Wu J, Zhang Y, Nie Y, Yan F, Zirbel CL, Bisaro DM. RNA three-dimensional structure drives the sequence organization of potato spindle tuber viroid quasispecies. PLoS Pathog 2024; 20:e1012142. [PMID: 38574111 PMCID: PMC11020406 DOI: 10.1371/journal.ppat.1012142] [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: 10/24/2023] [Revised: 04/16/2024] [Accepted: 03/22/2024] [Indexed: 04/06/2024] Open
Abstract
RNA viruses and viroids exist and evolve as quasispecies due to error-prone replication. Quasispecies consist of a few dominant master sequences alongside numerous variants that contribute to genetic diversity. Upon environmental changes, certain variants within quasispecies have the potential to become the dominant sequences, leading to the emergence of novel infectious strains. However, the emergence of new infectious variants remains unpredictable. Using mutant pools prepared by saturation mutagenesis of selected stem and loop regions, our study of potato spindle tuber viroid (PSTVd) demonstrates that mutants forming local three-dimensional (3D) structures similar to the wild type (WT) are more likely to accumulate in PSTVd quasispecies. The selection mechanisms underlying this biased accumulation are likely associated with cell-to-cell movement and long-distance trafficking. Moreover, certain trafficking-defective PSTVd mutants can be spread by functional sister genomes in the quasispecies. Our study reveals that the RNA 3D structure of stems and loops constrains the evolution of viroid quasispecies. Mutants with a structure similar to WT have a higher likelihood of being maintained within the quasispecies and can potentially give rise to novel infectious variants. These findings emphasize the potential of targeting RNA 3D structure as a more robust approach to defend against viroid infections.
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Affiliation(s)
- Jian Wu
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agroproducts, Institute of Plant Virology, Ningbo University, Ningbo, China
- Key Laboratory of Biotechnology in Plant Protection of MARA and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo, China
- Department of Molecular Genetics, Center for Applied Plant Sciences, Center for RNA Biology, and Infectious Diseases Institute, The Ohio State University, Columbus, Ohio, United States of America
| | - Yuhong Zhang
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agroproducts, Institute of Plant Virology, Ningbo University, Ningbo, China
- Key Laboratory of Biotechnology in Plant Protection of MARA and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo, China
| | - Yuxin Nie
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agroproducts, Institute of Plant Virology, Ningbo University, Ningbo, China
- Key Laboratory of Biotechnology in Plant Protection of MARA and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo, China
| | - Fei Yan
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agroproducts, Institute of Plant Virology, Ningbo University, Ningbo, China
- Key Laboratory of Biotechnology in Plant Protection of MARA and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo, China
| | - Craig L. Zirbel
- Department of Mathematics and Statistics, Bowling Green State University, Bowling Green, Ohio, United States of America
| | - David M. Bisaro
- Department of Molecular Genetics, Center for Applied Plant Sciences, Center for RNA Biology, and Infectious Diseases Institute, The Ohio State University, Columbus, Ohio, United States of America
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19
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Chakraborty C, Bhattacharya M, Sharma AR, Chatterjee S, Agoramoorthy G, Lee SS. Structural Landscape of nsp Coding Genomic Regions of SARS-CoV-2-ssRNA Genome: A Structural Genomics Approach Toward Identification of Druggable Genome, Ligand-Binding Pockets, and Structure-Based Druggability. Mol Biotechnol 2024; 66:641-662. [PMID: 36463562 PMCID: PMC9735222 DOI: 10.1007/s12033-022-00605-x] [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: 05/05/2022] [Accepted: 11/07/2022] [Indexed: 12/05/2022]
Abstract
SARS-CoV-2 has a single-stranded RNA genome (+ssRNA), and synthesizes structural and non-structural proteins (nsps). All 16 nsp are synthesized from the ORF1a, and ORF1b regions associated with different life cycle preprocesses, including replication. The regions of ORF1a synthesizes nsp1 to 11, and ORF1b synthesizes nsp12 to 16. In this paper, we have predicted the secondary structure conformations, entropy & mountain plots, RNA secondary structure in a linear fashion, and 3D structure of nsp coding genes of the SARS-CoV-2 genome. We have also analyzed the A, T, G, C, A+T, and G+C contents, GC-profiling of these genes, showing the range of the GC content from 34.23 to 48.52%. We have observed that the GC-profile value of the nsp coding genomic regions was less (about 0.375) compared to the whole genome (about 0.38). Additionally, druggable pockets were identified from the secondary structure-guided 3D structural conformations. For secondary structure generation of all the nsp coding genes (nsp 1-16), we used a recent algorithm-based tool (deep learning-based) along with the conventional algorithms (centroid and MFE-based) to develop secondary structural conformations, and we found stem-loop, multi-branch loop, pseudoknot, and the bulge structural components, etc. The 3D model shows bound and unbound forms, branched structures, duplex structures, three-way junctions, four-way junctions, etc. Finally, we identified binding pockets of nsp coding genes which will help as a fundamental resource for future researchers to develop RNA-targeted therapeutics using the druggable genome.
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Affiliation(s)
- Chiranjib Chakraborty
- Department of Biotechnology, School of Life Science and Biotechnology, Adamas University, Kolkata, West Bengal, 700126, India.
| | - Manojit Bhattacharya
- Department of Zoology, Fakir Mohan University, Vyasa Vihar, Balasore, Odisha, 756020, India
| | - Ashish Ranjan Sharma
- Institute for Skeletal Aging & Orthopaedic Surgery, Hallym University-Chuncheon Sacred Heart Hospital, Chuncheon-si, Gangwon-do, 24252, Republic of Korea
| | - Srijan Chatterjee
- Department of Biotechnology, School of Life Science and Biotechnology, Adamas University, Kolkata, West Bengal, 700126, India
| | | | - Sang-Soo Lee
- Institute for Skeletal Aging & Orthopaedic Surgery, Hallym University-Chuncheon Sacred Heart Hospital, Chuncheon-si, Gangwon-do, 24252, Republic of Korea
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20
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Dey A, Yan S, Schlick T, Laederach A. Abolished frameshifting for predicted structure-stabilizing SARS-CoV-2 mutants: Implications to alternative conformations and their statistical structural analyses. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.28.586935. [PMID: 38585719 PMCID: PMC10996636 DOI: 10.1101/2024.03.28.586935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
The SARS-CoV-2 frameshifting element (FSE) has been intensely studied and explored as a therapeutic target for coronavirus diseases including COVID-19. Besides the intriguing virology, this small RNA is known to adopt many length-dependent conformations, as verified by multiple experimental and computational approaches. However, the role these alternative conformations play in the frameshifting mechanism and how to quantify this structural abundance has been an ongoing challenge. Here, we show by DMS and dual-luciferase functional assays that previously predicted FSE mutants (using the RAG graph theory approach) suppress structural transitions and abolish frameshifting. Furthermore, correlated mutation analysis of DMS data by three programs (DREEM, DRACO, and DANCE-MaP) reveals important differences in their estimation of specific RNA conformations, suggesting caution in the interpretation of such complex conformational landscapes. Overall, the abolished frameshifting in three different mutants confirms that all alternative conformations play a role in the pathways of ribosomal transition.
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21
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Irving PS, Weeks KM. RNAvigate: efficient exploration of RNA chemical probing datasets. Nucleic Acids Res 2024; 52:2231-2241. [PMID: 38348910 PMCID: PMC10954457 DOI: 10.1093/nar/gkae089] [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: 04/30/2023] [Revised: 01/19/2024] [Accepted: 01/30/2024] [Indexed: 02/27/2024] Open
Abstract
Chemical probing technologies enable high-throughput examination of diverse structural features of RNA, including local nucleotide flexibility, RNA secondary structure, protein and ligand binding, through-space interaction networks, and multistate structural ensembles. Deep understanding of RNA structure-function relationships typically requires evaluating a system under structure- and function-altering conditions, linking these data with additional information, and visualizing multilayered relationships. Current platforms lack the broad accessibility, flexibility and efficiency needed to iterate on integrative analyses of these diverse, complex data. Here, we share the RNA visualization and graphical analysis toolset RNAvigate, a straightforward and flexible Python library that automatically parses 21 standard file formats (primary sequence annotations, per- and internucleotide data, and secondary and tertiary structures) and outputs 18 plot types. RNAvigate enables efficient exploration of nuanced relationships between multiple layers of RNA structure information and across multiple experimental conditions. Compatibility with Jupyter notebooks enables nonburdensome, reproducible, transparent and organized sharing of multistep analyses and data visualization strategies. RNAvigate simplifies and accelerates discovery and characterization of RNA-centric functions in biology.
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Affiliation(s)
- Patrick S Irving
- Department of Chemistry, University of North Carolina, Chapel Hill, NC 27599-3290, USA
| | - Kevin M Weeks
- Department of Chemistry, University of North Carolina, Chapel Hill, NC 27599-3290, USA
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22
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Kretsch RC, Xu L, Zheludev IN, Zhou X, Huang R, Nye G, Li S, Zhang K, Chiu W, Das R. Tertiary folds of the SL5 RNA from the 5' proximal region of SARS-CoV-2 and related coronaviruses. Proc Natl Acad Sci U S A 2024; 121:e2320493121. [PMID: 38427602 DOI: 10.1073/pnas.2320493121] [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: 11/26/2023] [Accepted: 01/05/2024] [Indexed: 03/03/2024] Open
Abstract
Coronavirus genomes sequester their start codons within stem-loop 5 (SL5), a structured, 5' genomic RNA element. In most alpha- and betacoronaviruses, the secondary structure of SL5 is predicted to contain a four-way junction of helical stems, some of which are capped with UUYYGU hexaloops. Here, using cryogenic electron microscopy (cryo-EM) and computational modeling with biochemically determined secondary structures, we present three-dimensional structures of SL5 from six coronaviruses. The SL5 domain of betacoronavirus severe-acute-respiratory-syndrome-related coronavirus 2 (SARS-CoV-2), resolved at 4.7 Å resolution, exhibits a T-shaped structure, with its UUYYGU hexaloops at opposing ends of a coaxial stack, the T's "arms." Further analysis of SL5 domains from SARS-CoV-1 and MERS (7.1 and 6.4 to 6.9 Å resolution, respectively) indicate that the junction geometry and inter-hexaloop distances are conserved features across these human-infecting betacoronaviruses. The MERS SL5 domain displays an additional tertiary interaction, which is also observed in the non-human-infecting betacoronavirus BtCoV-HKU5 (5.9 to 8.0 Å resolution). SL5s from human-infecting alphacoronaviruses, HCoV-229E and HCoV-NL63 (6.5 and 8.4 to 9.0 Å resolution, respectively), exhibit the same coaxial stacks, including the UUYYGU-capped arms, but with a phylogenetically distinct crossing angle, an X-shape. As such, all SL5 domains studied herein fold into stable tertiary structures with cross-genus similarities and notable differences, with implications for potential protein-binding modes and therapeutic targets.
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Affiliation(s)
| | - Lily Xu
- Department of Microbiology and Immunology, Stanford University, Stanford, CA 94305
| | - Ivan N Zheludev
- Department of Biochemistry, Stanford University, Stanford, CA 94305
| | - Xueting Zhou
- Department of Bioengineering, James H. Clark Center, Stanford University, Stanford, CA 94305
| | - Rui Huang
- Department of Biochemistry, Stanford University, Stanford, CA 94305
| | - Grace Nye
- Department of Biochemistry, Stanford University, Stanford, CA 94305
| | - Shanshan Li
- Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230027, China
| | - Kaiming Zhang
- Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230027, China
| | - Wah Chiu
- Biophysics Program, Stanford University, Stanford, CA 94305
- Department of Bioengineering, James H. Clark Center, Stanford University, Stanford, CA 94305
- CryoEM and Bioimaging Division, Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Stanford University, Menlo Park, CA 94025
| | - Rhiju Das
- Biophysics Program, Stanford University, Stanford, CA 94305
- Department of Biochemistry, Stanford University, Stanford, CA 94305
- HHMI, Stanford University, Stanford, CA 94305
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23
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Xiao L, Fang L, Kool ET. 2'-OH as a universal handle for studying intracellular RNAs. Cell Chem Biol 2024; 31:110-124. [PMID: 37992716 PMCID: PMC10841764 DOI: 10.1016/j.chembiol.2023.10.022] [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: 07/06/2023] [Revised: 09/28/2023] [Accepted: 10/29/2023] [Indexed: 11/24/2023]
Abstract
RNA plays pivotal roles in most cellular processes, serving as both the traditional carrier of genetic information and as a key regulator of cellular functions. The advent of chemical technologies has contributed critically to the analysis of cellular RNA structures, functions, and interactions. Many of these methods and molecules involve the utilization of chemically reactive handles in RNAs, either introduced externally or inherent within the polymer itself. Among these handles, the 2'-hydroxyl (2'-OH) group has emerged as an exceptionally well-suited and general chemical moiety for the modification and profiling of RNAs in intracellular studies. In this review, we provide an overview of the recent advancements in intracellular applications of acylation at the 2'-OH group of RNA. We outline progress made in probing RNA structure and interactomes, controlling RNA function, RNA imaging, and analyzing RNA-small molecule interactions, all achieved in living cells through this simple chemical handle on the biopolymer.
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Affiliation(s)
- Lu Xiao
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA
| | - Linglan Fang
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA
| | - Eric T Kool
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA; Sarafan ChEM-H, Stanford University, Stanford, CA 94305, USA.
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24
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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: 0] [Impact Index Per Article: 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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25
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Peterson JM, O'Leary CA, Coppenbarger EC, Tompkins VS, Moss WN. Discovery of RNA secondary structural motifs using sequence-ordered thermodynamic stability and comparative sequence analysis. MethodsX 2023; 11:102275. [PMID: 37448951 PMCID: PMC10336498 DOI: 10.1016/j.mex.2023.102275] [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: 12/15/2022] [Accepted: 06/28/2023] [Indexed: 07/18/2023] Open
Abstract
Major advances in RNA secondary structural motif prediction have been achieved in the last few years; however, few methods harness the predictive power of multiple approaches to deliver in-depth characterizations of local RNA motifs and their potential functionality. Additionally, most available methods do not predict RNA pseudoknots. This work combines complementary bioinformatic systems into one robust discovery pipeline where: •RNA sequences are folded to search for thermodynamically favorable motifs utilizing ScanFold.•Motifs are expanded and refolded into alternate pseudoknot conformations by Knotty/Iterative HFold.•All conformations are evaluated for covariance via the cm-builder pipeline (Infernal and R-scape).
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26
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Kretsch RC, Andersen ES, Bujnicki JM, Chiu W, Das R, Luo B, Masquida B, McRae EK, Schroeder GM, Su Z, Wedekind JE, Xu L, Zhang K, Zheludev IN, Moult J, Kryshtafovych A. RNA target highlights in CASP15: Evaluation of predicted models by structure providers. Proteins 2023; 91:1600-1615. [PMID: 37466021 PMCID: PMC10792523 DOI: 10.1002/prot.26550] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 06/16/2023] [Accepted: 06/26/2023] [Indexed: 07/20/2023]
Abstract
The first RNA category of the Critical Assessment of Techniques for Structure Prediction competition was only made possible because of the scientists who provided experimental structures to challenge the predictors. In this article, these scientists offer a unique and valuable analysis of both the successes and areas for improvement in the predicted models. All 10 RNA-only targets yielded predictions topologically similar to experimentally determined structures. For one target, experimentalists were able to phase their x-ray diffraction data by molecular replacement, showing a potential application of structure predictions for RNA structural biologists. Recommended areas for improvement include: enhancing the accuracy in local interaction predictions and increased consideration of the experimental conditions such as multimerization, structure determination method, and time along folding pathways. The prediction of RNA-protein complexes remains the most significant challenge. Finally, given the intrinsic flexibility of many RNAs, we propose the consideration of ensemble models.
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Affiliation(s)
- Rachael C. Kretsch
- Biophysics Program, Stanford University School of Medicine, Stanford, CA, USA
| | - Ebbe S. Andersen
- Interdisciplinary Nanoscience Center and Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Janusz M. Bujnicki
- International Institute of Molecular and Cell Biology in Warsaw, Warsaw, Poland
| | - Wah Chiu
- Biophysics Program, Stanford University School of Medicine, Stanford, CA, USA
- Department of Bioengineering and James H. Clark Center, Stanford University, Stanford, CA, USA
- Division of CryoEM and Bioimaging, SSRL, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Rhiju Das
- Biophysics Program, Stanford University School of Medicine, Stanford, CA, USA
- Department of Biochemistry, Stanford University School of Medicine, Stanford, CA, USA
- Howard Hughes Medical Institute, Stanford, CA, USA
| | - Bingnan Luo
- The State Key Laboratory of Biotherapy, Frontiers Medical Center of Tianfu Jincheng Laboratory, Department of Geriatrics and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu 610044, Sichuan, China
| | - Benoît Masquida
- UMR 7156, CNRS – Universite de Strasbourg, Strasbourg, France
| | - Ewan K.S. McRae
- Center for RNA Therapeutics, Houston Methodist Research Institute, Houston, TX 77030, USA
| | - Griffin M. Schroeder
- Department of Biochemistry and Biophysics, University of Rochester School of Medicine and Dentistry, Rochester, NY, 14642, USA
- Center for RNA Biology, University of Rochester School of Medicine and Dentistry, Rochester, NY, 14642, USA
| | - Zhaoming Su
- The State Key Laboratory of Biotherapy, Frontiers Medical Center of Tianfu Jincheng Laboratory, Department of Geriatrics and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu 610044, Sichuan, China
| | - Joseph E. Wedekind
- Department of Biochemistry and Biophysics, University of Rochester School of Medicine and Dentistry, Rochester, NY, 14642, USA
- Center for RNA Biology, University of Rochester School of Medicine and Dentistry, Rochester, NY, 14642, USA
| | - Lily Xu
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA, USA
| | - Kaiming Zhang
- Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230027, China
| | - Ivan N. Zheludev
- Department of Biochemistry, Stanford University School of Medicine, Stanford, CA, USA
| | - John Moult
- Department of Cell Biology and Molecular Genetics, Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, Maryland, USA
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27
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Baulin EF, Mukherjee S, Moafinejad SN, Wirecki TK, Badepally NG, Jaryani F, Stefaniak F, Amiri Farsani M, Ray A, Rocha de Moura T, Bujnicki JM. RNA tertiary structure prediction in CASP15 by the GeneSilico group: Folding simulations based on statistical potentials and spatial restraints. Proteins 2023; 91:1800-1810. [PMID: 37622458 DOI: 10.1002/prot.26575] [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: 04/15/2023] [Revised: 07/06/2023] [Accepted: 07/31/2023] [Indexed: 08/26/2023]
Abstract
Ribonucleic acid (RNA) molecules serve as master regulators of cells by encoding their biological function in the ribonucleotide sequence, particularly their ability to interact with other molecules. To understand how RNA molecules perform their biological tasks and to design new sequences with specific functions, it is of great benefit to be able to computationally predict how RNA folds and interacts in the cellular environment. Our workflow for computational modeling of the 3D structures of RNA and its interactions with other molecules uses a set of methods developed in our laboratory, including MeSSPredRNA for predicting canonical and non-canonical base pairs, PARNASSUS for detecting remote homology based on comparisons of sequences and secondary structures, ModeRNA for comparative modeling, the SimRNA family of programs for modeling RNA 3D structure and its complexes with other molecules, and QRNAS for model refinement. In this study, we present the results of testing this workflow in predicting RNA 3D structures in the CASP15 experiment. The overall high score of the computational models predicted by our group demonstrates the robustness of our workflow and its individual components in terms of predicting RNA 3D structures of acceptable quality that are close to the target structures. However, the variance in prediction quality is still quite high, and the results are still too far from the level of protein 3D structure predictions. This exercise led us to consider several improvements, especially to better predict and enforce stacking interactions and non-canonical base pairs.
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Affiliation(s)
- Eugene F Baulin
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, Warsaw, Poland
| | - Sunandan Mukherjee
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, Warsaw, Poland
| | - S Naeim Moafinejad
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, Warsaw, Poland
| | - Tomasz K Wirecki
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, Warsaw, Poland
| | - Nagendar Goud Badepally
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, Warsaw, Poland
| | - Farhang Jaryani
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, Warsaw, Poland
| | - Filip Stefaniak
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, Warsaw, Poland
| | - Masoud Amiri Farsani
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, Warsaw, Poland
| | - Angana Ray
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, Warsaw, Poland
| | - Tales Rocha de Moura
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, Warsaw, Poland
| | - Janusz M Bujnicki
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, Warsaw, Poland
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28
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Dauksaite V, Tas A, Wachowius F, Spruit A, van Hemert MJ, Snijder EJ, van der Veer EP, van Zonneveld AJ. Highly Potent Antisense Oligonucleotides Locked Nucleic Acid Gapmers Targeting the SARS-CoV-2 RNA Genome. Nucleic Acid Ther 2023; 33:381-385. [PMID: 37782140 DOI: 10.1089/nat.2023.0012] [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] [Indexed: 10/03/2023] Open
Abstract
The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has caused the current worldwide pandemic and the associated coronavirus disease 2019 with potentially lethal outcome. Although effective vaccines strongly contributed to reduce disease severity, establishing a toolbox to control current and newly emerging coronaviruses of epidemic concern requires the development of novel therapeutic compounds, to treat severely infected individuals and to prevent virus transmission. Here we present a therapeutic strategy targeting the SARS-CoV-2 RNA genome using antisense oligonucleotides (ASOs). We demonstrate that selected locked nucleic acid gapmers have the potency to reduce the in vitro intracellular viral load by up to 96%. Our promising results strongly support the case for further development of our preselected ASOs as therapeutic or prophylactic antiviral agents.
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Affiliation(s)
- Vita Dauksaite
- Einthoven Laboratory for Vascular and Regenerative Medicine, Department of Internal Medicine (Nephrology), Leiden University Medical Centre, Leiden, The Netherlands
| | - Ali Tas
- Department of Medical Microbiology, Leiden University Medical Centre, Leiden, The Netherlands
| | | | - Anouk Spruit
- Einthoven Laboratory for Vascular and Regenerative Medicine, Department of Internal Medicine (Nephrology), Leiden University Medical Centre, Leiden, The Netherlands
| | - Martijn J van Hemert
- Department of Medical Microbiology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Eric J Snijder
- Department of Medical Microbiology, Leiden University Medical Centre, Leiden, The Netherlands
| | | | - Anton Jan van Zonneveld
- Einthoven Laboratory for Vascular and Regenerative Medicine, Department of Internal Medicine (Nephrology), Leiden University Medical Centre, Leiden, The Netherlands
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29
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Kretsch RC, Xu L, Zheludev IN, Zhou X, Huang R, Nye G, Li S, Zhang K, Chiu W, Das R. Tertiary folds of the SL5 RNA from the 5' proximal region of SARS-CoV-2 and related coronaviruses. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.22.567964. [PMID: 38076883 PMCID: PMC10705266 DOI: 10.1101/2023.11.22.567964] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
Coronavirus genomes sequester their start codons within stem-loop 5 (SL5), a structured, 5' genomic RNA element. In most alpha- and betacoronaviruses, the secondary structure of SL5 is predicted to contain a four-way junction of helical stems, some of which are capped with UUYYGU hexaloops. Here, using cryogenic electron microscopy (cryo-EM) and computational modeling with biochemically-determined secondary structures, we present three-dimensional structures of SL5 from six coronaviruses. The SL5 domain of betacoronavirus SARS-CoV-2, resolved at 4.7 Å resolution, exhibits a T-shaped structure, with its UUYYGU hexaloops at opposing ends of a coaxial stack, the T's "arms." Further analysis of SL5 domains from SARS-CoV-1 and MERS (7.1 and 6.4-6.9 Å resolution, respectively) indicate that the junction geometry and inter-hexaloop distances are conserved features across the studied human-infecting betacoronaviruses. The MERS SL5 domain displays an additional tertiary interaction, which is also observed in the non-human-infecting betacoronavirus BtCoV-HKU5 (5.9-8.0 Å resolution). SL5s from human-infecting alphacoronaviruses, HCoV-229E and HCoV-NL63 (6.5 and 8.4-9.0 Å resolution, respectively), exhibit the same coaxial stacks, including the UUYYGU-capped arms, but with a phylogenetically distinct crossing angle, an X-shape. As such, all SL5 domains studied herein fold into stable tertiary structures with cross-genus similarities, with implications for potential protein-binding modes and therapeutic targets.
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Affiliation(s)
| | - Lily Xu
- Department of Microbiology and Immunology, Stanford University, Stanford, CA, USA
| | - Ivan N. Zheludev
- Department of Biochemistry, Stanford University, Stanford, CA, USA
| | - Xueting Zhou
- Department of Bioengineering, James H. Clark Center, Stanford University, Stanford, CA, USA
| | - Rui Huang
- Department of Biochemistry, Stanford University, Stanford, CA, USA
| | - Grace Nye
- Department of Biochemistry, Stanford University, Stanford, CA, USA
| | - Shanshan Li
- Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230027, China
| | - Kaiming Zhang
- Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230027, China
| | - Wah Chiu
- Biophysics Program, Stanford University, Stanford, CA, USA
- Department of Bioengineering, James H. Clark Center, Stanford University, Stanford, CA, USA
- CryoEM and Bioimaging Division, Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Stanford University, Menlo Park, CA, USA
| | - Rhiju Das
- Biophysics Program, Stanford University, Stanford, CA, USA
- Department of Biochemistry, Stanford University, Stanford, CA, USA
- Howard Hughes Medical Institute, Stanford, CA, USA
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30
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Haltom J, Trovao NS, Guarnieri J, Vincent P, Singh U, Tsoy S, O'Leary CA, Bram Y, Widjaja GA, Cen Z, Meller R, Baylin SB, Moss WN, Nikolau BJ, Enguita FJ, Wallace DC, Beheshti A, Schwartz R, Wurtele ES. SARS-CoV-2 Orphan Gene ORF10 Contributes to More Severe COVID-19 Disease. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.11.27.23298847. [PMID: 38076862 PMCID: PMC10705665 DOI: 10.1101/2023.11.27.23298847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/11/2024]
Abstract
The orphan gene of SARS-CoV-2, ORF10, is the least studied gene in the virus responsible for the COVID-19 pandemic. Recent experimentation indicated ORF10 expression moderates innate immunity in vitro. However, whether ORF10 affects COVID-19 in humans remained unknown. We determine that the ORF10 sequence is identical to the Wuhan-Hu-1 ancestral haplotype in 95% of genomes across five variants of concern (VOC). Four ORF10 variants are associated with less virulent clinical outcomes in the human host: three of these affect ORF10 protein structure, one affects ORF10 RNA structural dynamics. RNA-Seq data from 2070 samples from diverse human cells and tissues reveals ORF10 accumulation is conditionally discordant from that of other SARS-CoV-2 transcripts. Expression of ORF10 in A549 and HEK293 cells perturbs immune-related gene expression networks, alters expression of the majority of mitochondrially-encoded genes of oxidative respiration, and leads to large shifts in levels of 14 newly-identified transcripts. We conclude ORF10 contributes to more severe COVID-19 clinical outcomes in the human host.
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Affiliation(s)
- Jeffrey Haltom
- Department of Genetics Development and Cell Biology, Iowa State University, Ames, IA 50011, USA
- Center for Mitochondrial and Epigenomic Medicine, Division of Human Genetics, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
- COVID-19 International Research Team, Medford, MA 02155, USA
| | - Nidia S Trovao
- Division of International Epidemiology and Population Studies, Fogarty International Center, National Institutes of Health, Bethesda, Maryland, 20892, USA
- COVID-19 International Research Team, Medford, MA 02155, USA
| | - Joseph Guarnieri
- Center for Mitochondrial and Epigenomic Medicine, Division of Human Genetics, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
- COVID-19 International Research Team, Medford, MA 02155, USA
| | - Pan Vincent
- Division of International Epidemiology and Population Studies, Fogarty International Center, National Institutes of Health, Bethesda, Maryland, 20892, USA
| | - Urminder Singh
- Bioinformatics and Computational Biology Program, and Genetics Program, Iowa State University, Ames, IA 50011, USA
| | - Sergey Tsoy
- Division of Gastroenterology and Hepatology, Department of Medicine, Weill Cornell Medicine, New York, NY, USA
| | - Collin A O'Leary
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA 50011, USA
| | - Yaron Bram
- Division of Gastroenterology and Hepatology, Department of Medicine, Weill Cornell Medicine, New York, NY, USA
| | - Gabrielle A Widjaja
- Center for Mitochondrial and Epigenomic Medicine, Division of Human Genetics, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Zimu Cen
- Center for Mitochondrial and Epigenomic Medicine, Division of Human Genetics, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Robert Meller
- Morehouse School of Medicine, Atlanta, GA , 30310-1495, USA
| | - Stephen B Baylin
- Department of Oncology, Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21231
- Van Andel Research Institute, Grand Rapids, MI 49503
| | - Walter N Moss
- Bioinformatics and Computational Biology Program, and Genetics Program, Iowa State University, Ames, IA 50011, USA
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA 50011, USA
| | - Basil J Nikolau
- Bioinformatics and Computational Biology Program, and Genetics Program, Iowa State University, Ames, IA 50011, USA
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA 50011, USA
| | - Francisco J Enguita
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Douglas C Wallace
- Center for Mitochondrial and Epigenomic Medicine, Division of Human Genetics, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
- Department of Pediatrics, Division of Human Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Afshin Beheshti
- COVID-19 International Research Team, Medford, MA 02155, USA
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
- Blue Marble Space Institute of Science, Seattle, WA, 98104 USA
| | - Robert Schwartz
- Division of Gastroenterology and Hepatology, Department of Medicine, Weill Cornell Medicine, New York, NY, USA
- Department of Physiology, Biophysics and Systems Biology, Weill Cornell Medicine, New York, NY, USA
- Department of Biomedical Engineering, Cornell University, Ithaca, NY, USA
| | - Eve Syrkin Wurtele
- Bioinformatics and Computational Biology Program, and Genetics Program, Iowa State University, Ames, IA 50011, USA
- Department of Genetics Development and Cell Biology, Iowa State University, Ames, IA 50011, USA
- COVID-19 International Research Team, Medford, MA 02155, USA
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31
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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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32
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Tang Z, Hegde S, Hao S, Selvaraju M, Qiu J, Wang J. Chemical-guided SHAPE sequencing (cgSHAPE-seq) informs the binding site of RNA-degrading chimeras targeting SARS-CoV-2 5' untranslated region. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.03.535453. [PMID: 37066172 PMCID: PMC10103992 DOI: 10.1101/2023.04.03.535453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
One of the hallmarks of RNA viruses is highly structured untranslated regions (UTRs) in their genomes. These conserved RNA structures are often essential for viral replication, transcription, or translation. In this report, we discovered and optimized a new type of coumarin derivatives, such as C30 and C34, which bind to a four-way RNA helix called SL5 in the 5' UTR of the SARS-CoV-2 RNA genome. To locate the binding site, we developed a novel sequencing-based method namely cgSHAPE-seq, in which the acylating chemical probe was directed to crosslink with the 2'-OH groups of ribose at the ligand binding site. This crosslinked RNA could then create read-through mutations during reverse transcription (i.e., primer extension) at single-nucleotide resolution to uncover the acylation locations. cgSHAPE-seq unambiguously determined that a bulged G in SL5 was the primary binding site of C30 in the SARS-CoV-2 5' UTR, which was validated through mutagenesis and in vitro binding experiments. C30 was further used as a warhead in RNA-degrading chimeras to reduce viral RNA expression levels. We demonstrated that replacing the acylating moiety in the cgSHAPE probe with ribonuclease L recruiter (RLR) moieties yielded RNA degraders active in the in vitro RNase L degradation assay and SARS-CoV-2 5' UTR expressing cells. We further explored another RLR conjugation site on the E ring of C30/C34 and discovered improved RNA degradation activities in vitro and in cells. The optimized RNA-degrading chimera C64 inhibited live virus replication in lung epithelial carcinoma cells.
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Affiliation(s)
- Zhichao Tang
- Department of Medicinal Chemistry, University of Kansas, Lawrence, KS, USA
| | - Shalakha Hegde
- Department of Medicinal Chemistry, University of Kansas, Lawrence, KS, USA
| | - Siyuan Hao
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, KS, USA
| | | | - Jianming Qiu
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, KS, USA
| | - Jingxin Wang
- Department of Medicinal Chemistry, University of Kansas, Lawrence, KS, USA
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33
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Zhang H, Li S, Dai N, Zhang L, Mathews DH, Huang L. LinearCoFold and LinearCoPartition: linear-time algorithms for secondary structure prediction of interacting RNA molecules. Nucleic Acids Res 2023; 51:e94. [PMID: 37650626 PMCID: PMC10570024 DOI: 10.1093/nar/gkad664] [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: 12/01/2022] [Revised: 06/15/2023] [Accepted: 08/17/2023] [Indexed: 09/01/2023] Open
Abstract
Many RNAs function through RNA-RNA interactions. Fast and reliable RNA structure prediction with consideration of RNA-RNA interaction is useful, however, existing tools are either too simplistic or too slow. To address this issue, we present LinearCoFold, which approximates the complete minimum free energy structure of two strands in linear time, and LinearCoPartition, which approximates the cofolding partition function and base pairing probabilities in linear time. LinearCoFold and LinearCoPartition are orders of magnitude faster than RNAcofold. For example, on a sequence pair with combined length of 26,190 nt, LinearCoFold is 86.8× faster than RNAcofold MFE mode, and LinearCoPartition is 642.3× faster than RNAcofold partition function mode. Surprisingly, LinearCoFold and LinearCoPartition's predictions have higher PPV and sensitivity of intermolecular base pairs. Furthermore, we apply LinearCoFold to predict the RNA-RNA interaction between SARS-CoV-2 genomic RNA (gRNA) and human U4 small nuclear RNA (snRNA), which has been experimentally studied, and observe that LinearCoFold's prediction correlates better with the wet lab results than RNAcofold's.
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Affiliation(s)
- He Zhang
- Baidu Research, Sunnyvale, CA, USA
- School of Electrical Engineering & Computer Science, Oregon State University, Corvallis, OR, USA
| | - Sizhen Li
- School of Electrical Engineering & Computer Science, Oregon State University, Corvallis, OR, USA
| | - Ning Dai
- School of Electrical Engineering & Computer Science, Oregon State University, Corvallis, OR, USA
| | - Liang Zhang
- School of Electrical Engineering & Computer Science, Oregon State University, Corvallis, OR, USA
| | - David H Mathews
- Department of Biochemistry & Biophysics,Rochester, NY 14642, USA
- Center for RNA Biology, Rochester, NY 14642, USA
- Department of Biostatistics & Computational Biology, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Liang Huang
- School of Electrical Engineering & Computer Science, Oregon State University, Corvallis, OR, USA
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34
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Estelle AB, Forsythe HM, Yu Z, Hughes K, Lasher B, Allen P, Reardon PN, Hendrix DA, Barbar EJ. RNA structure and multiple weak interactions balance the interplay between RNA binding and phase separation of SARS-CoV-2 nucleocapsid. PNAS NEXUS 2023; 2:pgad333. [PMID: 37901441 PMCID: PMC10605006 DOI: 10.1093/pnasnexus/pgad333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Accepted: 10/02/2023] [Indexed: 10/31/2023]
Abstract
The nucleocapsid (N) protein of SARS-CoV-2 binds viral RNA, condensing it inside the virion, and phase separating with RNA to form liquid-liquid condensates. There is little consensus on what differentiates sequence-independent N-RNA interactions in the virion or in liquid droplets from those with specific genomic RNA (gRNA) motifs necessary for viral function inside infected cells. To identify the RNA structures and the N domains responsible for specific interactions and phase separation, we use the first 1,000 nt of viral RNA and short RNA segments designed as models for single-stranded and paired RNA. Binding affinities estimated from fluorescence anisotropy of these RNAs to the two-folded domains of N (the NTD and CTD) and comparison to full-length N demonstrate that the NTD binds preferentially to single-stranded RNA, and while it is the primary RNA-binding site, it is not essential to phase separation. Nuclear magnetic resonance spectroscopy identifies two RNA-binding sites on the NTD: a previously characterized site and an additional although weaker RNA-binding face that becomes prominent when binding to the primary site is weak, such as with dsRNA or a binding-impaired mutant. Phase separation assays of nucleocapsid domains with double-stranded and single-stranded RNA structures support a model where multiple weak interactions, such as with the CTD or the NTD's secondary face promote phase separation, while strong, specific interactions do not. These studies indicate that both strong and multivalent weak N-RNA interactions underlie the multifunctional abilities of N.
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Affiliation(s)
- Aidan B Estelle
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | - Heather M Forsythe
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | - Zhen Yu
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | - Kaitlyn Hughes
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | - Brittany Lasher
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | - Patrick Allen
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | - Patrick N Reardon
- Oregon State University NMR Facility, Oregon State University, Corvallis, OR 97331, USA
| | - David A Hendrix
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
- School of Electrical Engineering and Computer Science, Oregon State University, Corvallis, OR 97331, USA
| | - Elisar J Barbar
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
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35
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Williams AM, Jolley EA, Santiago-Martínez MG, Chan CX, Gutell RR, Ferry JG, Bevilacqua PC. In vivo structure probing of RNA in Archaea: novel insights into the ribosome structure of Methanosarcina acetivorans. RNA (NEW YORK, N.Y.) 2023; 29:1610-1620. [PMID: 37491319 PMCID: PMC10578495 DOI: 10.1261/rna.079687.123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 06/24/2023] [Indexed: 07/27/2023]
Abstract
Structure probing combined with next-generation sequencing (NGS) has provided novel insights into RNA structure-function relationships. To date, such studies have focused largely on bacteria and eukaryotes, with little attention given to the third domain of life, archaea. Furthermore, functional RNAs have not been extensively studied in archaea, leaving open questions about RNA structure and function within this domain of life. With archaeal species being diverse and having many similarities to both bacteria and eukaryotes, the archaea domain has the potential to be an evolutionary bridge. In this study, we introduce a method for probing RNA structure in vivo in the archaea domain of life. We investigated the structure of ribosomal RNA (rRNA) from Methanosarcina acetivorans, a well-studied anaerobic archaeal species, grown with either methanol or acetate. After probing the RNA in vivo with dimethyl sulfate (DMS), Structure-seq2 libraries were generated, sequenced, and analyzed. We mapped the reactivity of DMS onto the secondary structure of the ribosome, which we determined independently with comparative analysis, and confirmed the accuracy of DMS probing in M. acetivorans Accessibility of the rRNA to DMS in the two carbon sources was found to be quite similar, although some differences were found. Overall, this study establishes the Structure-seq2 pipeline in the archaea domain of life and informs about ribosomal structure within M. acetivorans.
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Affiliation(s)
- Allison M Williams
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Center for RNA Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Elizabeth A Jolley
- Center for RNA Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | | | - Cheong Xin Chan
- Australian Centre for Ecogenomics, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane QLD 4072, Australia
| | - Robin R Gutell
- Department of Integrative Biology, The University of Texas at Austin, Austin, Texas 78712, USA
| | - James G Ferry
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Philip C Bevilacqua
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Center for RNA Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, USA
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36
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Mitchell D, Cotter J, Saleem I, Mustoe AM. Mutation signature filtering enables high-fidelity RNA structure probing at all four nucleobases with DMS. Nucleic Acids Res 2023; 51:8744-8757. [PMID: 37334863 PMCID: PMC10484685 DOI: 10.1093/nar/gkad522] [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: 04/08/2023] [Revised: 05/30/2023] [Accepted: 06/02/2023] [Indexed: 06/21/2023] Open
Abstract
Chemical probing experiments have transformed RNA structure analysis, enabling high-throughput measurement of base-pairing in living cells. Dimethyl sulfate (DMS) is one of the most widely used structure probing reagents and has played a pivotal role in enabling next-generation single-molecule probing analyses. However, DMS has traditionally only been able to probe adenine and cytosine nucleobases. We previously showed that, using appropriate conditions, DMS can also be used to interrogate base-pairing of uracil and guanines in vitro at reduced accuracy. However, DMS remained unable to informatively probe guanines in cells. Here, we develop an improved DMS mutational profiling (MaP) strategy that leverages the unique mutational signature of N1-methylguanine DMS modifications to enable high-fidelity structure probing at all four nucleotides, including in cells. Using information theory, we show that four-base DMS reactivities convey greater structural information than current two-base DMS and SHAPE probing strategies. Four-base DMS experiments further enable improved direct base-pair detection by single-molecule PAIR analysis, and ultimately support RNA structure modeling at superior accuracy. Four-base DMS probing experiments are straightforward to perform and will broadly facilitate improved RNA structural analysis in living cells.
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Affiliation(s)
- David Mitchell
- Therapeutic Innovation Center, Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Jennifer Cotter
- Therapeutic Innovation Center, Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Irfana Saleem
- Therapeutic Innovation Center, Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Anthony M Mustoe
- Therapeutic Innovation Center, Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX, USA
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
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37
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Mathez G, Cagno V. Small Molecules Targeting Viral RNA. Int J Mol Sci 2023; 24:13500. [PMID: 37686306 PMCID: PMC10487773 DOI: 10.3390/ijms241713500] [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: 08/02/2023] [Revised: 08/25/2023] [Accepted: 08/28/2023] [Indexed: 09/10/2023] Open
Abstract
The majority of antivirals available target viral proteins; however, RNA is emerging as a new and promising antiviral target due to the presence of highly structured RNA in viral genomes fundamental for their replication cycle. Here, we discuss methods for the identification of RNA-targeting compounds, starting from the determination of RNA structures either from purified RNA or in living cells, followed by in silico screening on RNA and phenotypic assays to evaluate viral inhibition. Moreover, we review the small molecules known to target the programmed ribosomal frameshifting element of SARS-CoV-2, the internal ribosomal entry site of different viruses, and RNA elements of HIV.
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Affiliation(s)
| | - Valeria Cagno
- Institute of Microbiology, University Hospital of Lausanne, University of Lausanne, 1011 Lausanne, Switzerland
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38
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Jiang H, Joshi A, Gan T, Janowski AB, Fujii C, Bricker TL, Darling TL, Harastani HH, Seehra K, Chen H, Tahan S, Jung A, Febles B, Blatter JA, Handley SA, Parikh BA, Wang D, Boon ACM. The Highly Conserved Stem-Loop II Motif Is Dispensable for SARS-CoV-2. J Virol 2023; 97:e0063523. [PMID: 37223945 PMCID: PMC10308922 DOI: 10.1128/jvi.00635-23] [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: 04/28/2023] [Accepted: 05/01/2023] [Indexed: 05/25/2023] Open
Abstract
The stem-loop II motif (s2m) is an RNA structural element that is found in the 3' untranslated region (UTR) of many RNA viruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Though the motif was discovered over 25 years ago, its functional significance is unknown. In order to understand the importance of s2m, we created viruses with deletions or mutations of the s2m by reverse genetics and also evaluated a clinical isolate harboring a unique s2m deletion. Deletion or mutation of the s2m had no effect on growth in vitro or on growth and viral fitness in Syrian hamsters in vivo. We also compared the secondary structure of the 3' UTR of wild-type and s2m deletion viruses using selective 2'-hydroxyl acylation analyzed by primer extension and mutational profiling (SHAPE-MaP) and dimethyl sulfate mutational profiling and sequencing (DMS-MaPseq). These experiments demonstrate that the s2m forms an independent structure and that its deletion does not alter the overall remaining 3'-UTR RNA structure. Together, these findings suggest that s2m is dispensable for SARS-CoV-2. IMPORTANCE RNA viruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), contain functional structures to support virus replication, translation, and evasion of the host antiviral immune response. The 3' untranslated region of early isolates of SARS-CoV-2 contained a stem-loop II motif (s2m), which is an RNA structural element that is found in many RNA viruses. This motif was discovered over 25 years ago, but its functional significance is unknown. We created SARS-CoV-2 with deletions or mutations of the s2m and determined the effect of these changes on viral growth in tissue culture and in rodent models of infection. Deletion or mutation of the s2m element had no effect on growth in vitro or on growth and viral fitness in Syrian hamsters in vivo. We also observed no impact of the deletion on other known RNA structures in the same region of the genome. These experiments demonstrate that s2m is dispensable for SARS-CoV-2.
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Affiliation(s)
- Hongbing Jiang
- School of Public Health (Shenzhen), Sun Yat-sen University, Shenzhen, China
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Astha Joshi
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Tianyu Gan
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Andrew B. Janowski
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Chika Fujii
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Traci L. Bricker
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Tamarand L. Darling
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Houda H. Harastani
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Kuljeet Seehra
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Hongwei Chen
- School of Public Health (Shenzhen), Sun Yat-sen University, Shenzhen, China
| | - Stephen Tahan
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Ana Jung
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Binita Febles
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Joshua A. Blatter
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Scott A. Handley
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Bijal A. Parikh
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - David Wang
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, USA
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Adrianus C. M. Boon
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, USA
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, USA
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39
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Zhang D, Qiao L, Lei X, Dong X, Tong Y, Wang J, Wang Z, Zhou R. Mutagenesis and structural studies reveal the basis for the specific binding of SARS-CoV-2 SL3 RNA element with human TIA1 protein. Nat Commun 2023; 14:3715. [PMID: 37349329 PMCID: PMC10287707 DOI: 10.1038/s41467-023-39410-8] [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: 10/04/2022] [Accepted: 06/12/2023] [Indexed: 06/24/2023] Open
Abstract
Viral RNA-host protein interactions are indispensable during RNA virus transcription and replication, but their detailed structural and dynamical features remain largely elusive. Here, we characterize the binding interface for the SARS-CoV-2 stem-loop 3 (SL3) cis-acting element to human TIA1 protein with a combined theoretical and experimental approaches. The highly structured SARS-CoV-2 SL3 has a high binding affinity to TIA1 protein, in which the aromatic stacking, hydrogen bonds, and hydrophobic interactions collectively direct this specific binding. Further mutagenesis studies validate our proposed 3D binding model and reveal two SL3 variants have enhanced binding affinities to TIA1. And disruptions of the identified RNA-protein interactions with designed antisense oligonucleotides dramatically reduce SARS-CoV-2 infection in cells. Finally, TIA1 protein could interact with conserved SL3 RNA elements within other betacoronavirus lineages. These findings open an avenue to explore the viral RNA-host protein interactions and provide a pioneering structural basis for RNA-targeting antiviral drug design.
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Affiliation(s)
- Dong Zhang
- Institute of Quantitative Biology, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, 310058, China
| | - Lulu Qiao
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, 310058, China
| | - Xiaobo Lei
- NHC Key Laboratory of Systems Biology of Pathogens and Christophe Mérieux Laboratory, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100730, China
| | - Xiaojing Dong
- NHC Key Laboratory of Systems Biology of Pathogens and Christophe Mérieux Laboratory, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100730, China
| | - Yunguang Tong
- College of Life Sciences, China Jiliang University, Hangzhou, Zhejiang, 310018, China
- Department of Pharmacy, China Jiliang University, Hangzhou, Zhejiang, 310018, China
| | - Jianwei Wang
- NHC Key Laboratory of Systems Biology of Pathogens and Christophe Mérieux Laboratory, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100730, China.
| | - Zhiye Wang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, 310058, China.
- The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, 310058, China.
| | - Ruhong Zhou
- Institute of Quantitative Biology, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, 310058, China.
- The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, 310058, China.
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40
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Balaratnam S, Torrey ZR, Calabrese DR, Banco MT, Yazdani K, Liang X, Fullenkamp CR, Seshadri S, Holewinski RJ, Andresson T, Ferré-D'Amaré AR, Incarnato D, Schneekloth JS. Investigating the NRAS 5' UTR as a target for small molecules. Cell Chem Biol 2023; 30:643-657.e8. [PMID: 37257453 DOI: 10.1016/j.chembiol.2023.05.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 02/24/2023] [Accepted: 05/10/2023] [Indexed: 06/02/2023]
Abstract
Neuroblastoma RAS (NRAS) is an oncogene that is deregulated and highly mutated in cancers including melanomas and acute myeloid leukemias. The 5' untranslated region (UTR) (5' UTR) of the NRAS mRNA contains a G-quadruplex (G4) that regulates translation. Here we report a novel class of small molecule that binds to the G4 structure located in the 5' UTR of the NRAS mRNA. We used a small molecule microarray screen to identify molecules that selectively bind to the NRAS-G4 with submicromolar affinity. One compound inhibits the translation of NRAS in vitro but showed only moderate effects on the NRAS levels in cellulo. Rapid Amplification of cDNA Ends and RT-PCR analysis revealed that the predominant NRAS transcript does not possess the G4 structure. Thus, although NRAS transcripts lack a G4 in many cell lines the concept of targeting folded regions within 5' UTRs to control translation remains a highly attractive strategy.
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Affiliation(s)
- Sumirtha Balaratnam
- Chemical Biology Laboratory, National Cancer Institute, Frederick, MD 21702, USA
| | - Zachary R Torrey
- Chemical Biology Laboratory, National Cancer Institute, Frederick, MD 21702, USA
| | - David R Calabrese
- Chemical Biology Laboratory, National Cancer Institute, Frederick, MD 21702, USA
| | - Michael T Banco
- Biochemistry and Biophysics Center, National Heart, Lung and Blood Institute, Bethesda, MD 20892, USA
| | - Kamyar Yazdani
- Chemical Biology Laboratory, National Cancer Institute, Frederick, MD 21702, USA
| | - Xiao Liang
- Chemical Biology Laboratory, National Cancer Institute, Frederick, MD 21702, USA
| | | | - Srinath Seshadri
- Chemical Biology Laboratory, National Cancer Institute, Frederick, MD 21702, USA
| | - Ronald J Holewinski
- Protein Characterization Laboratory, Cancer Research Technology Program, Frederick National Laboratory for Cancer Research, Leidos Biomedical Research, Inc, Frederick, MD 21702, USA
| | - Thorkell Andresson
- Protein Characterization Laboratory, Cancer Research Technology Program, Frederick National Laboratory for Cancer Research, Leidos Biomedical Research, Inc, Frederick, MD 21702, USA
| | - Adrian R Ferré-D'Amaré
- Biochemistry and Biophysics Center, National Heart, Lung and Blood Institute, Bethesda, MD 20892, USA
| | - Danny Incarnato
- Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, Groningen, the Netherlands
| | - John S Schneekloth
- Chemical Biology Laboratory, National Cancer Institute, Frederick, MD 21702, USA.
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41
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Yang M, Olatunji FP, Rhodes C, Balaratnam S, Dunne-Dombrink K, Seshadri S, Liang X, Jones CP, Le Grice SFJ, Ferré-D’Amaré AR, Schneekloth JS. Discovery of Small Molecules Targeting the Frameshifting Element RNA in SARS-CoV-2 Viral Genome. ACS Med Chem Lett 2023; 14:757-765. [PMID: 37312842 PMCID: PMC10258829 DOI: 10.1021/acsmedchemlett.3c00051] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 05/02/2023] [Indexed: 06/15/2023] Open
Abstract
Targeting structured RNA elements in the SARS-CoV-2 viral genome with small molecules is an attractive strategy for pharmacological control over viral replication. In this work, we report the discovery of small molecules that target the frameshifting element (FSE) in the SARS-CoV-2 RNA genome using high-throughput small-molecule microarray (SMM) screening. A new class of aminoquinazoline ligands for the SARS-CoV-2 FSE are synthesized and characterized using multiple orthogonal biophysical assays and structure-activity relationship (SAR) studies. This work reveals compounds with mid-micromolar binding affinity (KD = 60 ± 6 μM) to the FSE RNA and supports a binding mode distinct from previously reported FSE binders MTDB and merafloxacin. In addition, compounds are active in in vitro dual-luciferase and in-cell dual-fluorescent-reporter frameshifting assays, highlighting the promise of targeting structured elements of RNAs with druglike compounds to alter expression of viral proteins.
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Affiliation(s)
- Mo Yang
- Chemical
Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, Maryland 21702-1201, United States
| | - Feyisola P. Olatunji
- Chemical
Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, Maryland 21702-1201, United States
| | - Curran Rhodes
- Chemical
Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, Maryland 21702-1201, United States
| | - Sumirtha Balaratnam
- Chemical
Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, Maryland 21702-1201, United States
| | - Kara Dunne-Dombrink
- Chemical
Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, Maryland 21702-1201, United States
| | - Srinath Seshadri
- Chemical
Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, Maryland 21702-1201, United States
| | - Xiao Liang
- Chemical
Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, Maryland 21702-1201, United States
| | - Christopher P. Jones
- Biochemistry
and Biophysics Center, National Heart, Lung,
and Blood Institute, Bethesda, Maryland 20892, United States
| | - Stuart F. J. Le Grice
- Cancer
Innovation Laboratory, Center for Cancer Research, National Cancer Institute, Frederick Maryland 21702-1201, United States
| | - Adrian R. Ferré-D’Amaré
- Biochemistry
and Biophysics Center, National Heart, Lung,
and Blood Institute, Bethesda, Maryland 20892, United States
| | - John S. Schneekloth
- Chemical
Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, Maryland 21702-1201, United States
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42
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Korn SM, Dhamotharan K, Jeffries CM, Schlundt A. The preference signature of the SARS-CoV-2 Nucleocapsid NTD for its 5'-genomic RNA elements. Nat Commun 2023; 14:3331. [PMID: 37286558 DOI: 10.1038/s41467-023-38882-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Accepted: 05/17/2023] [Indexed: 06/09/2023] Open
Abstract
The nucleocapsid protein (N) of SARS-CoV-2 plays a pivotal role during the viral life cycle. It is involved in RNA transcription and accounts for packaging of the large genome into virus particles. N manages the enigmatic balance of bulk RNA-coating versus precise RNA-binding to designated cis-regulatory elements. Numerous studies report the involvement of its disordered segments in non-selective RNA-recognition, but how N organizes the inevitable recognition of specific motifs remains unanswered. We here use NMR spectroscopy to systematically analyze the interactions of N's N-terminal RNA-binding domain (NTD) with individual cis RNA elements clustering in the SARS-CoV-2 regulatory 5'-genomic end. Supported by broad solution-based biophysical data, we unravel the NTD RNA-binding preferences in the natural genome context. We show that the domain's flexible regions read the intrinsic signature of preferred RNA elements for selective and stable complex formation within the large pool of available motifs.
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Affiliation(s)
- Sophie Marianne Korn
- Institute for Molecular Biosciences, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438, Frankfurt/M., Germany
- Center for Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Max-von-Laue-Str. 7, 60438, Frankfurt/M., Germany
| | - Karthikeyan Dhamotharan
- Institute for Molecular Biosciences, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438, Frankfurt/M., Germany
- Center for Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Max-von-Laue-Str. 7, 60438, Frankfurt/M., Germany
| | - Cy M Jeffries
- European Molecular Biology Laboratory (EMBL) Hamburg Site, c/o Deutsches Elektronen-Synchrotron, Notkestr. 85, 22607, Hamburg, Germany
| | - Andreas Schlundt
- Institute for Molecular Biosciences, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438, Frankfurt/M., Germany.
- Center for Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Max-von-Laue-Str. 7, 60438, Frankfurt/M., Germany.
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43
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Gao W, Yang A, Rivas E. Thirteen dubious ways to detect conserved structural RNAs. IUBMB Life 2023; 75:471-492. [PMID: 36495545 PMCID: PMC11234323 DOI: 10.1002/iub.2694] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 10/24/2022] [Indexed: 12/14/2022]
Abstract
Covariation induced by compensatory base substitutions in RNA alignments is a great way to deduce conserved RNA structure, in principle. In practice, success depends on many factors, importantly the quality and depth of the alignment and the choice of covariation statistic. Measuring covariation between pairs of aligned positions is easy. However, using covariation to infer evolutionarily conserved RNA structure is complicated by other extraneous sources of covariation such as that resulting from homologous sequences having evolved from a common ancestor. In order to provide evidence of evolutionarily conserved RNA structure, a method to distinguish covariation due to sources other than RNA structure is necessary. Moreover, there are several sorts of artifactually generated covariation signals that can further confound the analysis. Additionally, some covariation signal is difficult to detect due to incomplete comparative data. Here, we investigate and critically discuss the practice of inferring conserved RNA structure by comparative sequence analysis. We provide new methods on how to approach and decide which of the numerous long non-coding RNAs (lncRNAs) have biologically relevant structures.
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Affiliation(s)
- William Gao
- Department of Genetics, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ann Yang
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts, USA
| | - Elena Rivas
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts, USA
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44
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Assmann SM, Chou HL, Bevilacqua PC. Rock, scissors, paper: How RNA structure informs function. THE PLANT CELL 2023; 35:1671-1707. [PMID: 36747354 DOI: 10.1093/plcell/koad026] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 01/05/2023] [Accepted: 01/30/2023] [Indexed: 05/30/2023]
Abstract
RNA can fold back on itself to adopt a wide range of structures. These range from relatively simple hairpins to intricate 3D folds and can be accompanied by regulatory interactions with both metabolites and macromolecules. The last 50 yr have witnessed elucidation of an astonishing array of RNA structures including transfer RNAs, ribozymes, riboswitches, the ribosome, the spliceosome, and most recently entire RNA structuromes. These advances in RNA structural biology have deepened insight into fundamental biological processes including gene editing, transcription, translation, and structure-based detection and response to temperature and other environmental signals. These discoveries reveal that RNA can be relatively static, like a rock; that it can have catalytic functions of cutting bonds, like scissors; and that it can adopt myriad functional shapes, like paper. We relate these extraordinary discoveries in the biology of RNA structure to the plant way of life. We trace plant-specific discovery of ribozymes and riboswitches, alternative splicing, organellar ribosomes, thermometers, whole-transcriptome structuromes and pan-structuromes, and conclude that plants have a special set of RNA structures that confer unique types of gene regulation. We finish with a consideration of future directions for the RNA structure-function field.
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Affiliation(s)
- Sarah M Assmann
- Department of Biology, Pennsylvania State University, University Park, PA 16802, USA
- Center for RNA Molecular Biology, Pennsylvania State University, University Park, PA 16802, USA
| | - Hong-Li Chou
- Department of Biology, Pennsylvania State University, University Park, PA 16802, USA
| | - Philip C Bevilacqua
- Center for RNA Molecular Biology, Pennsylvania State University, University Park, PA 16802, USA
- Department of Chemistry, Pennsylvania State University, University Park, PA 16802, USA
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA 16802, USA
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45
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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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46
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Mirska B, Woźniak T, Lorent D, Ruszkowska A, Peterson JM, Moss WN, Mathews DH, Kierzek R, Kierzek E. In vivo secondary structural analysis of Influenza A virus genomic RNA. Cell Mol Life Sci 2023; 80:136. [PMID: 37131079 PMCID: PMC10153785 DOI: 10.1007/s00018-023-04764-1] [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: 10/28/2022] [Revised: 03/19/2023] [Accepted: 03/19/2023] [Indexed: 05/04/2023]
Abstract
Influenza A virus (IAV) is a respiratory virus that causes epidemics and pandemics. Knowledge of IAV RNA secondary structure in vivo is crucial for a better understanding of virus biology. Moreover, it is a fundament for the development of new RNA-targeting antivirals. Chemical RNA mapping using selective 2'-hydroxyl acylation analyzed by primer extension (SHAPE) coupled with Mutational Profiling (MaP) allows for the thorough examination of secondary structures in low-abundance RNAs in their biological context. So far, the method has been used for analyzing the RNA secondary structures of several viruses including SARS-CoV-2 in virio and in cellulo. Here, we used SHAPE-MaP and dimethyl sulfate mutational profiling with sequencing (DMS-MaPseq) for genome-wide secondary structure analysis of viral RNA (vRNA) of the pandemic influenza A/California/04/2009 (H1N1) strain in both in virio and in cellulo environments. Experimental data allowed the prediction of the secondary structures of all eight vRNA segments in virio and, for the first time, the structures of vRNA5, 7, and 8 in cellulo. We conducted a comprehensive structural analysis of the proposed vRNA structures to reveal the motifs predicted with the highest accuracy. We also performed a base-pairs conservation analysis of the predicted vRNA structures and revealed many highly conserved vRNA motifs among the IAVs. The structural motifs presented herein are potential candidates for new IAV antiviral strategies.
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Affiliation(s)
- Barbara Mirska
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704, Poznan, Poland
| | - Tomasz Woźniak
- Institute of Human Genetics, Polish Academy of Sciences, Strzeszynska 32, 60-479, Poznan, Poland
| | - Dagny Lorent
- 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
| | - Jake M Peterson
- Roy J. Carver Department of Biophysics, Biochemistry and Molecular Biology, Iowa State University, Ames, IA, 50011, USA
| | - Walter N Moss
- Roy J. Carver Department of Biophysics, Biochemistry and Molecular Biology, Iowa State University, Ames, IA, 50011, USA
| | - David H Mathews
- Department of Biochemistry & Biophysics and Center for RNA Biology, School of Medicine and Dentistry, University of Rochester, 601 Elmwood Avenue, Box 712, Rochester, NY, 14642, USA
| | - Ryszard Kierzek
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704, Poznan, Poland
| | - Elzbieta Kierzek
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704, Poznan, Poland.
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47
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AlMalki FA, Albukhaty S, Alyamani AA, Khalaf MN, Thomas S. The relevant information about the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) using the five-question approach (when, where, what, why, and how) and its impact on the environment. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:61430-61454. [PMID: 35175517 PMCID: PMC8852932 DOI: 10.1007/s11356-022-18868-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Accepted: 01/21/2022] [Indexed: 05/08/2023]
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is regarded as a threat because it spreads quickly across the world without requiring a passport or establishing an identity. This tiny virus has wreaked havoc on people's lives, killed people, and created psychological problems all over the world. The viral spike protein (S) significantly contributes to host cell entry, and mutations associated with it, particularly in the receptor-binding protein (RBD), either facilitate the escape of virus from neutralizing antibodies or enhance its transmission by increasing the affinity for cell entry receptor, angiotensin-converting enzyme 2 (ACE2). The initial variants identified in Brazil, South Africa, and the UK have spread to various countries. On the other hand, new variants are being detected in India and the USA. The viral genome and proteome were applied for molecular detection techniques, and nanotechnology particles and materials were utilized in protection and prevention strategies. Consequently, the SARS-CoV-2 pandemic has resulted in extraordinary scientific community efforts to develop detection methods, diagnosis tools, and effective antiviral drugs and vaccines, where prevailing academic, governmental, and industrial institutions and organizations continue to engage themselves in large-scale screening of existing drugs, both in vitro and in vivo. In addition, COVID-19 pointed on the possible solutions for the environmental pollution globe problem. Therefore, this review aims to address SARS-CoV-2, its transmission, where it can be found, why it is severe in some people, how it can be stopped, its diagnosis and detection techniques, and its relationship with the environment.
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Affiliation(s)
- Faizah A AlMalki
- Department of Biology, College of Science, Taif University, P.O. Box 11099, Taif, 21944, Kingdom of Saudi Arabia.
| | - Salim Albukhaty
- Deptartment of Chemistry, College of Science, University of Misan, Maysan, 62001, Iraq
| | - Amal A Alyamani
- Department of Biotechnology, College of Science, Taif University, P.O. Box 11099, Taif, 21944, Kingdom of Saudi Arabia
| | - Moayad N Khalaf
- Deptartment of Chemistry, College of Science, University of Basrah, Basrah, Iraq
| | - Sabu Thomas
- Centre for Nanoscience and Nanotechnology, Mahatma Gandhi University, Kottayam, Kerala, 686 560, India
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48
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Atari N, Erster O, Shteinberg YH, Asraf H, Giat E, Mandelboim M, Goldstein I. Proof-of-concept for effective antiviral activity of an in silico designed decoy synthetic mRNA against SARS-CoV-2 in the Vero E6 cell-based infection model. Front Microbiol 2023; 14:1113697. [PMID: 37152730 PMCID: PMC10157240 DOI: 10.3389/fmicb.2023.1113697] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 04/03/2023] [Indexed: 05/09/2023] Open
Abstract
The positive-sense single-stranded (ss) RNA viruses of the Betacoronavirus (beta-CoV) genus can spillover from mammals to humans and are an ongoing threat to global health and commerce, as demonstrated by the current zoonotic pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Current anti-viral strategies focus on vaccination or targeting key viral proteins with antibodies and drugs. However, the ongoing evolution of new variants that evade vaccination or may become drug-resistant is a major challenge. Thus, antiviral compounds that circumvent these obstacles are needed. Here we describe an innovative antiviral modality based on in silico designed fully synthetic mRNA that is replication incompetent in uninfected cells (termed herein PSCT: parasitic anti-SARS-CoV-2 transcript). The PSCT sequence was engineered to include key untranslated cis-acting regulatory RNA elements of the SARS-CoV-2 genome, so as to effectively compete for replication and packaging with the standard viral genome. Using the Vero E6 cell-culture based SARS-CoV-2 infection model, we determined that the intracellular delivery of liposome-encapsulated PSCT at 1 hour post infection significantly reduced intercellular SARS-CoV-2 replication and release into the extracellular milieu as compared to mock treatment. In summary, our findings are a proof-of-concept for the therapeutic feasibility of in silico designed mRNA compounds formulated to hinder the replication and packaging of ssRNA viruses sharing a comparable genomic-structure with beta-CoVs.
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Affiliation(s)
- Nofar Atari
- Central Virology Laboratory, Public Health Services, Ministry of Health, Sheba Medical Center, Tel HaShomer, Israel
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Oran Erster
- Central Virology Laboratory, Public Health Services, Ministry of Health, Sheba Medical Center, Tel HaShomer, Israel
| | | | - Hadar Asraf
- Central Virology Laboratory, Public Health Services, Ministry of Health, Sheba Medical Center, Tel HaShomer, Israel
| | - Eitan Giat
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
- The Department of Medicine, Sheba Medical Center, Ramat Gan, Israel
| | - Michal Mandelboim
- Central Virology Laboratory, Public Health Services, Ministry of Health, Sheba Medical Center, Tel HaShomer, Israel
- The Department of Medicine, Sheba Medical Center, Ramat Gan, Israel
| | - Itamar Goldstein
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
- The Department of Medicine, Sheba Medical Center, Ramat Gan, Israel
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49
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Mitchell D, Cotter J, Saleem I, Mustoe AM. Mutation signature filtering enables high-fidelity RNA structure probing at all four nucleobases with DMS. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.10.536308. [PMID: 37090560 PMCID: PMC10120657 DOI: 10.1101/2023.04.10.536308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
Abstract
Chemical probing experiments have transformed RNA structure analysis, enabling high-throughput measurement of base-pairing in living cells. Dimethyl sulfate (DMS) is one of the most widely used structure probing reagents and has played a prominent role in enabling next-generation single-molecule probing analyses. However, DMS has traditionally only been able to probe adenine and cytosine nucleobases. We previously showed that, using appropriate conditions, DMS can also be used to interrogate base-pairing of uracil and guanines in vitro at reduced accuracy. However, DMS remained unable to informatively probe guanines in cells. Here, we develop an improved DMS mutational profiling (MaP) strategy that leverages the unique mutational signature of N 1 -methylguanine DMS modifications to enable robust, high-fidelity structure probing at all four nucleotides, including in cells. Using information theory, we show that four-base DMS reactivities convey greater structural information than comparable two-base DMS and SHAPE probing strategies. Four-base DMS experiments further enable improved direct base-pair detection by single-molecule PAIR analysis, and ultimately support RNA structure modeling at superior accuracy. Four-base DMS probing experiments are easily performed and will broadly facilitate improved RNA structural analysis in living cells.
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Affiliation(s)
- David Mitchell
- Therapeutic Innovation Center, and Verna and Marrs Mclean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX
| | - Jennifer Cotter
- Therapeutic Innovation Center, and Verna and Marrs Mclean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX
| | - Irfana Saleem
- Therapeutic Innovation Center, and Verna and Marrs Mclean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX
| | - Anthony M. Mustoe
- Therapeutic Innovation Center, and Verna and Marrs Mclean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX
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50
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Forstmeier PC, Meyer MO, Bevilacqua PC. The Functional RNA Identification (FRID) Pipeline: Identification of Potential Pseudoknot-Containing RNA Elements as Therapeutic Targets for SARS-CoV-2. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.03.535424. [PMID: 37066195 PMCID: PMC10103974 DOI: 10.1101/2023.04.03.535424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/22/2023]
Abstract
The COVID-19 pandemic persists despite the development of effective vaccines. As such, it remains crucial to identify new targets for antiviral therapies. The causative virus of COVID-19, SARS-CoV-2, is a positive-sense RNA virus with RNA structures that could serve as therapeutic targets. One such RNA with established function is the frameshift stimulatory element (FSE), which promotes programmed ribosomal frameshifting. To accelerate identification of additional functional RNA elements, we introduce a novel computational approach termed the Functional RNA Identification (FRID) pipeline. The guiding principle of our pipeline, which uses established component programs as well as customized component programs, is that functional RNA elements have conserved secondary and pseudoknot structures that facilitate function. To assess the presence and conservation of putative functional RNA elements in SARS-CoV-2, we compared over 6,000 SARS-CoV-2 genomic isolates. We identified 22 functional RNA elements from the SARS-CoV-2 genome, 14 of which have conserved pseudoknots and serve as potential targets for small molecule or antisense oligonucleotide therapeutics. The FRID pipeline is general and can be applied to identify pseudoknotted RNAs for targeted therapeutics in genomes or transcriptomes from any virus or organism.
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