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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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2
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Jaramillo-Mesa H, Rakotondrafara AM. All eggs in one basket: How potyvirus infection is controlled at a single cap-independent translation event. Semin Cell Dev Biol 2023; 148-149:51-61. [PMID: 36608998 DOI: 10.1016/j.semcdb.2022.12.011] [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: 10/27/2022] [Revised: 12/28/2022] [Accepted: 12/30/2022] [Indexed: 01/06/2023]
Abstract
Regulation of protein synthesis is a strong determinant of potyviral pathogenicity. The Potyviridae family is the largest family of plant-infecting positive sense RNA viruses. Similar to the animal-infecting Picornaviridae family, the potyviral RNA genome lacks a 5' cap, and instead has a viral protein (VPg) linked to its 5' end. Potyviral genomes are mainly translated into one large polyprotein relying on a single translation event to express all their protein repertoire. In the absence of the 5' cap, the Potyviridae family depends on cis-acting elements in their 5' untranslated regions (UTR) to recruit the translation machinery. In this review, we summarize the diverse 5'UTR-driven, cap-independent translation mechanisms employed by the Potyviridae family including scanning-dependent mechanism, internal initiation, and the stimulatory role of the VPg. These mechanisms have direct implications on potyviral pathogenicity, including host range specificity and resistance. Finally, we discuss how these viral strategies could not only inform new avenues for engineering and/or breeding for crop resistance but would also provide opportunities for the development of biotechnological tools for large-scale protein production in plant systems.
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Affiliation(s)
- Helena Jaramillo-Mesa
- Department of Plant Pathology, University of Wisconsin-Madison, 1630 Linden Drive, Madison, WI 53704, USA
| | - Aurélie M Rakotondrafara
- Department of Plant Pathology, University of Wisconsin-Madison, 1630 Linden Drive, Madison, WI 53704, USA.
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3
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Martín-Villamil M, Sanmartín I, Moreno Á, Gallego J. Pharmacophore-Based Discovery of Viral RNA Conformational Modulators. Pharmaceuticals (Basel) 2022; 15:ph15060748. [PMID: 35745667 PMCID: PMC9229403 DOI: 10.3390/ph15060748] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 06/09/2022] [Accepted: 06/11/2022] [Indexed: 02/05/2023] Open
Abstract
New RNA-binding small-molecule scaffolds are needed to unleash the pharmacological potential of RNA targets. Here we have applied a pharmacophore-based virtual screening approach, seldom used in the RNA recognition field, to identify novel conformational inhibitors of the hepatitis C virus internal ribosome entry site. The conformational effect of the screening hits was assessed with a fluorescence resonance energy transfer assay, and the affinity, specificity, and binding site of the ligands were determined using a combination of fluorescence intensity and NMR spectroscopy experiments. The results indicate that this strategy can be successfully applied to discover RNA conformational inhibitors bearing substantially less positive charge than the reference ligands. This methodology can potentially be accommodated to other RNA motifs of pharmacological interest, facilitating the discovery of novel RNA-targeted molecules.
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4
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Conserved RNA secondary structure in Cherry virus A 5'-UTR associated with translation regulation. Virol J 2022; 19:91. [PMID: 35619168 PMCID: PMC9137147 DOI: 10.1186/s12985-022-01824-z] [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: 01/27/2022] [Accepted: 05/18/2022] [Indexed: 11/14/2022] Open
Abstract
Background A variety of cis-acting RNA elements with structures in the 5′- or 3′-untranslated region (UTR) of viral genomes play key roles in viral translation. Cherry virus A (CVA) is a member of the genus Capillovirus in the family Betaflexiviridae. It has a positive single-stranded RNA genome of ~ 7400 nucleotides (nt). The length of the CVA 5′-UTR is ~ 100 nt; however, the function of this long UTR has not yet been reported. Methods Molecular and phylogenetic analyses were performed on 75 CVA sequences, which could be divided into four groups, and the RNA secondary structure was predicted in four CVA 5′-UTR types. These four CVA 5′-UTR types were then inserted upstream of the firefly luciferase reporter gene FLuc (FLuc), and in vitro translation of the corresponding transcripts was evaluated using wheat germ extract (WGE). Then, in-line structure probing was performed to reveal the conserved RNA structures in CVA-5′UTR. Results The four CVA 5′-UTR types appeared to have a conserved RNA structure, and the FLuc construct containing these four CVA 5′-UTR types increased the translation of FLuc by 2–3 folds, suggesting weak translation enhancement activity. Mutations in CVA 5′-UTR suppressed translation, suggesting that the conserved RNA structure was important for function. Conclusion The conserved RNA secondary structure was identified by structural evolution analysis of different CVA isolates and was found to regulate translation.
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Francisco-Velilla R, Embarc-Buh A, Abellan S, Martinez-Salas E. Picornavirus translation strategies. FEBS Open Bio 2022; 12:1125-1141. [PMID: 35313388 PMCID: PMC9157412 DOI: 10.1002/2211-5463.13400] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 02/02/2022] [Accepted: 03/18/2022] [Indexed: 12/15/2022] Open
Abstract
The genome of viruses classified as picornaviruses consists of a single monocistronic positive strand RNA. The coding capacity of these RNA viruses is rather limited, and thus, they rely on the cellular machinery for their viral replication cycle. Upon the entry of the virus into susceptible cells, the viral RNA initially competes with cellular mRNAs for access to the protein synthesis machinery. Not surprisingly, picornaviruses have evolved specialized strategies that successfully allow the expression of viral gene products, which we outline in this review. The main feature of all picornavirus genomes is the presence of a heavily structured RNA element on the 5´UTR, referred to as an internal ribosome entry site (IRES) element, which directs viral protein synthesis as well and, consequently, triggers the subsequent steps required for viral replication. Here, we will summarize recent studies showing that picornavirus IRES elements consist of a modular structure, providing sites of interaction for ribosome subunits, eIFs, and a selective group of RNA‐binding proteins.
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Affiliation(s)
| | - Azman Embarc-Buh
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Madrid, Spain
| | - Salvador Abellan
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Madrid, Spain
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6
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Translation of Plant RNA Viruses. Viruses 2021; 13:v13122499. [PMID: 34960768 PMCID: PMC8708638 DOI: 10.3390/v13122499] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2021] [Revised: 12/01/2021] [Accepted: 12/09/2021] [Indexed: 11/16/2022] Open
Abstract
Plant RNA viruses encode essential viral proteins that depend on the host translation machinery for their expression. However, genomic RNAs of most plant RNA viruses lack the classical characteristics of eukaryotic cellular mRNAs, such as mono-cistron, 5′ cap structure, and 3′ polyadenylation. To adapt and utilize the eukaryotic translation machinery, plant RNA viruses have evolved a variety of translation strategies such as cap-independent translation, translation recoding on initiation and termination sites, and post-translation processes. This review focuses on advances in cap-independent translation and translation recoding in plant viruses.
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Zafferani M, Haddad C, Luo L, Davila-Calderon J, Chiu LY, Mugisha CS, Monaghan AG, Kennedy AA, Yesselman JD, Gifford RJ, Tai AW, Kutluay SB, Li ML, Brewer G, Tolbert BS, Hargrove AE. Amilorides inhibit SARS-CoV-2 replication in vitro by targeting RNA structures. SCIENCE ADVANCES 2021; 7:eabl6096. [PMID: 34826236 PMCID: PMC8626076 DOI: 10.1126/sciadv.abl6096] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 10/06/2021] [Indexed: 05/15/2023]
Abstract
The SARS-CoV-2 pandemic, and the likelihood of future coronavirus pandemics, emphasized the urgent need for development of novel antivirals. Small-molecule chemical probes offer both to reveal aspects of virus replication and to serve as leads for antiviral therapeutic development. Here, we report on the identification of amiloride-based small molecules that potently inhibit OC43 and SARS-CoV-2 replication through targeting of conserved structured elements within the viral 5′-end. Nuclear magnetic resonance–based structural studies revealed specific amiloride interactions with stem loops containing bulge like structures and were predicted to be strongly bound by the lead amilorides in retrospective docking studies. Amilorides represent the first antiviral small molecules that target RNA structures within the 5′ untranslated regions and proximal region of the CoV genomes. These molecules will serve as chemical probes to further understand CoV RNA biology and can pave the way for the development of specific CoV RNA–targeted antivirals.
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Affiliation(s)
- Martina Zafferani
- Chemistry Department, Duke University, 124 Science Drive, Durham, NC 27705, USA
| | - Christina Haddad
- Department of Chemistry, Case Western Reserve University, Cleveland, OH 441106, USA
| | - Le Luo
- Department of Chemistry, Case Western Reserve University, Cleveland, OH 441106, USA
| | | | - Liang-Yuan Chiu
- Department of Chemistry, Case Western Reserve University, Cleveland, OH 441106, USA
| | - Christian Shema Mugisha
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Adeline G. Monaghan
- Chemistry Department, Duke University, 124 Science Drive, Durham, NC 27705, USA
| | - Andrew A. Kennedy
- Department of Internal Medicine and Department of Microbiology and Immunology, University of Michigan, 1150 W Medical Center Dr., Ann Arbor, MI 48109, USA
| | - Joseph D. Yesselman
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln, NE 68588, USA
| | - Robert J. Gifford
- MRC-University of Glasgow Centre for Virus Research, 464 Bearsden Rd., Bearsden, Glasgow G61 1QH, UK
| | - Andrew W. Tai
- Department of Internal Medicine and Department of Microbiology and Immunology, University of Michigan, 1150 W Medical Center Dr., Ann Arbor, MI 48109, USA
| | - Sebla B. Kutluay
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Mei-Ling Li
- Department of Biochemistry and Molecular Biology, Rutgers Robert Wood Johnson Medical School, 675 Hoes Lane West, Piscataway, NJ 08854, USA
| | - Gary Brewer
- Department of Biochemistry and Molecular Biology, Rutgers Robert Wood Johnson Medical School, 675 Hoes Lane West, Piscataway, NJ 08854, USA
| | - Blanton S. Tolbert
- Department of Chemistry, Case Western Reserve University, Cleveland, OH 441106, USA
| | - Amanda E. Hargrove
- Chemistry Department, Duke University, 124 Science Drive, Durham, NC 27705, USA
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8
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Reprogramming translation for gene therapy. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2021; 182:439-476. [PMID: 34175050 DOI: 10.1016/bs.pmbts.2021.01.028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Translational control plays a fundamental role in the regulation of gene expression in eukaryotes. Modulating translational efficiency allows the cell to fine-tune the expression of genes, spatially control protein localization, and trigger fast responses to environmental stresses. Translational regulation involves mechanisms acting on multiple steps of the protein synthesis pathway: initiation, elongation, and termination. Many cis-acting elements present in the 5' UTR of transcripts can influence translation at the initiation step. Among them, the Kozak sequence impacts translational efficiency by regulating the recognition of the start codon; upstream open reading frames (uORFs) are associated with inhibition of translation of the downstream protein; internal ribosomal entry sites (IRESs) can promote cap-independent translation. CRISPR-Cas technology is a revolutionary gene-editing tool that has also been applied to the regulation of gene expression. In this chapter, we focus on the genome editing approaches developed to modulate the translational efficiency with the aim to find novel therapeutic approaches, in particular acting on the cis-elements, that regulate the initiation of protein synthesis.
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Rangel-Guerrero SI, Franco-Urquijo PA, Martínez-Salas E, Alvarez-Salas LM. Structural insights of the pre-let-7 interaction with LIN28B. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2020; 40:194-211. [PMID: 33319653 DOI: 10.1080/15257770.2020.1859116] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
The Let-7:LIN28 regulatory loop is a paradigm in miRNA regulation. LIN28 harbors two RNA binding domains, which interact with well-conserved sequences in pre-let-7 RNAs, the GNGAY and the GGAG motifs. Here, the differential binding between LIN28B and pre-let-7 members was associated with the structural characteristics of the pre-let-7 family mapped by SHAPE, uncovering diverse structural patterns within pre-let-7 members. Pre-let-7 mutants supported a relevant role of the GGAG motif location and the preE-stem stability for the interaction with LIN28B. Based on these results, we propose a core RNA structure for LIN28B interaction.
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Affiliation(s)
- Sergio Israel Rangel-Guerrero
- Laboratorio de Terapia Génica, Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del IPN, México City, Mexico
| | - Pablo Alberto Franco-Urquijo
- Laboratorio de Terapia Génica, Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del IPN, México City, Mexico
| | | | - Luis Marat Alvarez-Salas
- Laboratorio de Terapia Génica, Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del IPN, México City, Mexico
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Martina Z, Christina H, Le L, Jesse DC, Liang YC, Christian SM, Monaghan AG, Kennedy AA, Yesselman JD, Gifford RR, Tai AW, Kutluay SB, Li ML, Brewer G, Tolbert BS, Hargrove AE. Amilorides inhibit SARS-CoV-2 replication in vitro by targeting RNA structures. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2020:2020.12.05.409821. [PMID: 33299997 PMCID: PMC7724665 DOI: 10.1101/2020.12.05.409821] [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: 01/12/2023]
Abstract
The SARS-CoV-2 pandemic, and the likelihood of future coronavirus pandemics, has rendered our understanding of coronavirus biology more essential than ever. Small molecule chemical probes offer to both reveal novel aspects of virus replication and to serve as leads for antiviral therapeutic development. The RNA-biased amiloride scaffold was recently tuned to target a viral RNA structure critical for translation in enterovirus 71, ultimately uncovering a novel mechanism to modulate positive-sense RNA viral translation and replication. Analysis of CoV RNA genomes reveal many conserved RNA structures in the 5'-UTR and proximal region critical for viral translation and replication, including several containing bulge-like secondary structures suitable for small molecule targeting. Following phylogenetic conservation analysis of this region, we screened an amiloride-based small molecule library against a less virulent human coronavirus, OC43, to identify lead ligands. Amilorides inhibited OC43 replication as seen in viral plaque assays. Select amilorides also potently inhibited replication competent SARS-CoV-2 as evident in the decreased levels of cell free virions in cell culture supernatants of treated cells. Reporter screens confirmed the importance of RNA structures in the 5'-end of the viral genome for small molecule activity. Finally, NMR chemical shift perturbation studies of the first six stem loops of the 5'-end revealed specific amiloride interactions with stem loops 4, 5a, and 6, all of which contain bulge like structures and were predicted to be strongly bound by the lead amilorides in retrospective docking studies. Taken together, the use of multiple orthogonal approaches allowed us to identify the first small molecules aimed at targeting RNA structures within the 5'-UTR and proximal region of the CoV genome. These molecules will serve as chemical probes to further understand CoV RNA biology and can pave the way for the development of specific CoV RNA-targeted antivirals.
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Affiliation(s)
- Zafferani Martina
- Chemistry Department, Duke University, 124 Science Drive; Durham, NC USA 27705
| | - Haddad Christina
- Department of Chemistry, Case Western Reserve University, Cleveland OH 441106
| | - Luo Le
- Department of Chemistry, Case Western Reserve University, Cleveland OH 441106
| | | | - Yuan-Chiu Liang
- Department of Chemistry, Case Western Reserve University, Cleveland OH 441106
| | - Shema Mugisha Christian
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Adeline G. Monaghan
- Chemistry Department, Duke University, 124 Science Drive; Durham, NC USA 27705
| | - Andrew A. Kennedy
- Department of Internal Medicine and Department of Microbiology & Immunology, University of Michigan, 1150 W Medical Center Dr, Ann Arbor MI 48109
| | - Joseph D. Yesselman
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln, NE 68588 USA
| | - Robert R. Gifford
- MRC-University of Glasgow Centre for Virus Research, 464 Bearsden Rd, Bearsden, Glasgow, UK, G61 1QH
| | - Andrew W. Tai
- Department of Internal Medicine and Department of Microbiology & Immunology, University of Michigan, 1150 W Medical Center Dr, Ann Arbor MI 48109
| | - Sebla B. Kutluay
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Mei-Ling Li
- Department of Biochemistry and Molecular Biology, Rutgers Robert Wood Johnson Medical School, 675 Hoes Lane West, Piscataway, NJ USA 08854
| | - Gary Brewer
- Department of Biochemistry and Molecular Biology, Rutgers Robert Wood Johnson Medical School, 675 Hoes Lane West, Piscataway, NJ USA 08854
| | - Blanton S. Tolbert
- Department of Chemistry, Case Western Reserve University, Cleveland OH 441106
| | - Amanda E. Hargrove
- Chemistry Department, Duke University, 124 Science Drive; Durham, NC USA 27705
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11
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Davila-Calderon J, Patwardhan NN, Chiu LY, Sugarman A, Cai Z, Penutmutchu SR, Li ML, Brewer G, Hargrove AE, Tolbert BS. IRES-targeting small molecule inhibits enterovirus 71 replication via allosteric stabilization of a ternary complex. Nat Commun 2020; 11:4775. [PMID: 32963221 PMCID: PMC7508794 DOI: 10.1038/s41467-020-18594-3] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Accepted: 08/21/2020] [Indexed: 12/22/2022] Open
Abstract
Enterovirus 71 (EV71) poses serious threats to human health, particularly in Southeast Asia, and no drugs or vaccines are available. Previous work identified the stem loop II structure of the EV71 internal ribosomal entry site as vital to viral translation and a potential target. After screening an RNA-biased library using a peptide-displacement assay, we identify DMA-135 as a dose-dependent inhibitor of viral translation and replication with no significant toxicity in cell-based studies. Structural, biophysical, and biochemical characterization support an allosteric mechanism in which DMA-135 induces a conformational change in the RNA structure that stabilizes a ternary complex with the AUF1 protein, thus repressing translation. This mechanism is supported by pull-down experiments in cell culture. These detailed studies establish enterovirus RNA structures as promising drug targets while revealing an approach and mechanism of action that should be broadly applicable to functional RNA targeting. Human enterovirus 71 (EV71) contains an internal ribosome entry site (IRES) that promotes translation of viral RNA. Here the authors show that an antiviral small molecule DMA-135 binds to the EV71 IRES RNA, inducing conformational change and stabilizing a ternary complex to repress translation.
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Affiliation(s)
| | | | - Liang-Yuan Chiu
- Department of Chemistry, Case Western Reserve University, Cleveland, OH, USA
| | - Andrew Sugarman
- Department of Chemistry, Case Western Reserve University, Cleveland, OH, USA
| | - Zhengguo Cai
- Department of Chemistry, Duke University, Durham, NC, USA
| | | | - Mei-Ling Li
- Department of Biochemistry and Molecular Biology, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ, USA
| | - Gary Brewer
- Department of Biochemistry and Molecular Biology, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ, USA.
| | | | - Blanton S Tolbert
- Department of Chemistry, Case Western Reserve University, Cleveland, OH, USA.
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12
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Francisco-Velilla R, Embarc-Buh A, Rangel-Guerrero S, Basu S, Kundu S, Martinez-Salas E. RNA-protein coevolution study of Gemin5 uncovers the role of the PXSS motif of RBS1 domain for RNA binding. RNA Biol 2020; 17:1331-1341. [PMID: 32476560 DOI: 10.1080/15476286.2020.1762054] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Regulation of protein synthesis is an essential step of gene expression. This process is under the control of cis-acting RNA elements and trans-acting factors. Gemin5 is a multifunctional RNA-binding protein organized in distinct domains. The protein bears a non-canonical RNA-binding site, designated RBS1, at the C-terminal end. Among other cellular RNAs, the RBS1 region recognizes a sequence located within the coding region of Gemin5 mRNA, termed H12. Expression of RBS1 stimulates translation of RNA reporters carrying the H12 sequence, counteracting the negative effect of Gemin5 on global protein synthesis. A computational analysis of RBS1 protein and H12 RNA variability across the evolutionary scale predicts coevolving pairs of amino acids and nucleotides. RBS1 footprint and gel-shift assays indicated a positive correlation between the identified coevolving pairs and RNA-protein interaction. The coevolving residues of RBS1 contribute to the recognition of stem-loop SL1, an RNA structural element of H12 that contains the coevolving nucleotides. Indeed, RBS1 proteins carrying substitutions on the coevolving residues P1297 or S1299S1300, drastically reduced SL1-binding. Unlike the wild type RBS1 protein, expression of these mutant proteins in cells failed to enhance translation stimulation of mRNA reporters carrying the H12 sequence. Therefore, the PXSS motif within the RBS1 domain of Gemin5 and the RNA structural motif SL1 of its mRNA appears to play a key role in fine-tuning the expression level of this essential protein.
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Affiliation(s)
| | - Azman Embarc-Buh
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM , Madrid, Spain
| | - Sergio Rangel-Guerrero
- Laboratorio de Terapia Génica, Centro de Investigación y de Estudios Avanzados del I.P.N ., Ciudad de México, Mexico
| | - Sudipto Basu
- Department of Biophysics, Molecular Biology and Bioinformatics, University of Calcutta , Kolkata, India.,Center of Excellence in Systems Biology and Biomedical Engineering, TEQIP Phase-III, University of Calcutta , Kolkata, India
| | - Sudip Kundu
- Department of Biophysics, Molecular Biology and Bioinformatics, University of Calcutta , Kolkata, India.,Center of Excellence in Systems Biology and Biomedical Engineering, TEQIP Phase-III, University of Calcutta , Kolkata, India
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13
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Geng G, Yu C, Li X, Yuan X. A unique internal ribosome entry site representing a dynamic equilibrium state of RNA tertiary structure in the 5'-UTR of Wheat yellow mosaic virus RNA1. Nucleic Acids Res 2020; 48:390-404. [PMID: 31713626 PMCID: PMC7145537 DOI: 10.1093/nar/gkz1073] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 10/23/2019] [Accepted: 10/31/2019] [Indexed: 02/02/2023] Open
Abstract
Internal ribosome entry sites (IRESes) were first reported in RNA viruses and subsequently identified in cellular mRNAs. In this study, IRES activity of the 5'-UTR in Wheat yellow mosaic virus (WYMV) RNA1 was identified, and the 3'-UTR synergistically enhanced this IRES activity via long-distance RNA-RNA interaction between C80U81and A7574G7575. Within the 5'-UTR, the hairpin 1(H1), flexible hairpin 2 (H2) and linker region (LR1) between H1 and H2 played an essential role in cap-independent translation, which is associated with the structural stability of H1, length of discontinuous stems and nucleotide specificity of the H2 upper loop and the long-distance RNA-RNA interaction sites in LR1. The H2 upper loop is a target region of the eIF4E. Cytosines (C55, C66, C105 and C108) in H1 and H2 and guanines (G73, G79 and G85) in LR1 form discontinuous and alternative base pairing to maintain the dynamic equilibrium state, which is used to elaborately regulate translation at a suitable level. The WYMV RNA1 5'-UTR contains a novel IRES, which is different from reported IRESes because of the dynamic equilibrium state. It is also suggested that robustness not at the maximum level of translation is the selection target during evolution of WYMV RNA1.
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Affiliation(s)
- Guowei Geng
- Department of Plant Pathology, College of Plant Protection, Shandong Agricultural University, Shandong Province Key Laboratory of Agricultural Microbiology, Tai'an 271018, P.R. China
| | - Chengming Yu
- Department of Plant Pathology, College of Plant Protection, Shandong Agricultural University, Shandong Province Key Laboratory of Agricultural Microbiology, Tai'an 271018, P.R. China
| | - Xiangdong Li
- Department of Plant Pathology, College of Plant Protection, Shandong Agricultural University, Shandong Province Key Laboratory of Agricultural Microbiology, Tai'an 271018, P.R. China
| | - Xuefeng Yuan
- Department of Plant Pathology, College of Plant Protection, Shandong Agricultural University, Shandong Province Key Laboratory of Agricultural Microbiology, Tai'an 271018, P.R. China
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14
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Zheng GZ, Li W, Liu ZY. Alternative role of noncoding RNAs: coding and noncoding properties. J Zhejiang Univ Sci B 2019; 20:920-927. [PMID: 31595728 DOI: 10.1631/jzus.b1900336] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Noncoding RNAs (ncRNAs) have played a critical role in cellular biological functions. Recently, some peptides or proteins originating from annotated ncRNAs were identified in organism development and various diseases. Here, we briefly review several novel peptides translated by annotated ncRNAs and related key functions. In addition, we summarize the potential mechanism of bifunctional ncRNAs and propose a specific "switch" triggering the transformation from the noncoding to the coding state under certain stimuli or cellular stress. The coding properties of ncRNAs and their peptide products may provide a novel horizon in proteomic research and can be regarded as a potential therapeutic target for the treatment of various diseases.
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Affiliation(s)
- Gui-Zhen Zheng
- Department of Emergency Internal Medicine, Shanghai East Hospital, Tongji University, Shanghai 200120, China
| | - Wei Li
- Department of General Surgery, Changzheng Hospital, Second Military Medical University, Shanghai 200003, China
| | - Zhi-Yong Liu
- Department of Laboratory Diagnostics, Changhai Hospital, Second Military Medical University, Shanghai 200433, China.,Kunming General Hospital of Chengdu Military Command, Kunming 650032, China
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Cheng MSQ, Su MXX, Wang MXN, Sun MZY, Ou TM. Probes and drugs that interfere with protein translation via targeting to the RNAs or RNA-protein interactions. Methods 2019; 167:124-133. [PMID: 31185274 DOI: 10.1016/j.ymeth.2019.06.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 04/08/2019] [Accepted: 06/05/2019] [Indexed: 11/18/2022] Open
Abstract
Protein synthesis is critical to cell survival and translation regulation is essential to post-transcriptional gene expression regulation. Disorders of this process, particularly through RNA-binding proteins, is associated with the development and progression of a number of diseases, including cancers. However, the molecular mechanisms underlying the initiation of protein synthesis are intricate, making it difficult to find a drug that interferes with this process. Chemical probes are useful in elucidating the structures of RNA-protein complex and molecular mechanism of biological events. Moreover, some of these chemical probes show certain therapeutic benefits and can be further developed as leading compounds. Here, we will briefly review the general process and mechanism of protein synthesis, and emphasis on chemical probes in examples of probing the RNA structural changes and RNA-protein interactions. Moreover, the therapeutic potential of these probes is also discussed to give a comprehensive understanding.
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Affiliation(s)
- Miss Sui-Qi Cheng
- Sun Yat-Sen University, School of Pharmaceutical Sciences, Guangzhou, Guangdong 510006, China
| | - Miss Xiao-Xuan Su
- Sun Yat-Sen University, School of Pharmaceutical Sciences, Guangzhou, Guangdong 510006, China.
| | - Miss Xiao-Na Wang
- Sun Yat-Sen University, School of Pharmaceutical Sciences, Guangzhou, Guangdong 510006, China
| | - Miss Zhi-Yin Sun
- Sun Yat-Sen University, School of Pharmaceutical Sciences, Guangzhou, Guangdong 510006, China
| | - Tian-Miao Ou
- Sun Yat-Sen University, School of Pharmaceutical Sciences, 132 Waihuan East Road, Guangzhou University City, Guangzhou, Guangdong, China.
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16
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Umuhire Juru A, Patwardhan NN, Hargrove AE. Understanding the Contributions of Conformational Changes, Thermodynamics, and Kinetics of RNA-Small Molecule Interactions. ACS Chem Biol 2019; 14:824-838. [PMID: 31042354 DOI: 10.1021/acschembio.8b00945] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The implication of RNA in multiple cellular processes beyond protein coding has revitalized interest in the development of small molecules for therapeutically targeting RNA and for further probing its cellular biology. However, the process of rationally designing such small molecule probes is hampered by the paucity of information about fundamental molecular recognition principles of RNA. In this Review, we summarize two important and often underappreciated aspects of RNA-small molecule recognition: RNA conformational dynamics and the biophysical properties of interactions of small molecules with RNA, specifically thermodynamics and kinetics. While conformational flexibility is often said to impede RNA ligand development, the ability of small molecules to influence the RNA conformational landscape can have a significant effect on the cellular functions of RNA. An analysis of the conformational landscape of RNA and the interactions of individual conformations with ligands can thus guide the development of new small molecule probes, which needs to be investigated further. Additionally, while it is common practice to quantify the binding affinities ( Ka or Kd) of small molecules for biomacromolecules as a measure of their activity, further biophysical characterization of their interaction can provide a deeper understanding. Studies that focus on the thermodynamic and kinetic parameters for interaction between RNA and ligands are next discussed. Finally, this Review provides the reader with a perspective on how such in-depth analysis of biophysical characteristics of the interaction of RNA and small molecules can impact our understanding of these interactions and how they will benefit the future design of small molecule probes.
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Affiliation(s)
- Aline Umuhire Juru
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Neeraj N. Patwardhan
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Amanda E. Hargrove
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
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17
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Lozano G, Francisco-Velilla R, Martinez-Salas E. Deconstructing internal ribosome entry site elements: an update of structural motifs and functional divergences. Open Biol 2018; 8:rsob.180155. [PMID: 30487301 PMCID: PMC6282068 DOI: 10.1098/rsob.180155] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 10/30/2018] [Indexed: 12/16/2022] Open
Abstract
Beyond the general cap-dependent translation initiation, eukaryotic organisms use alternative mechanisms to initiate protein synthesis. Internal ribosome entry site (IRES) elements are cis-acting RNA regions that promote internal initiation of translation using a cap-independent mechanism. However, their lack of primary sequence and secondary RNA structure conservation, as well as the diversity of host factor requirement to recruit the ribosomal subunits, suggest distinct types of IRES elements. In spite of this heterogeneity, conserved motifs preserve sequences impacting on RNA structure and RNA–protein interactions important for IRES-driven translation. This conservation brings the question of whether IRES elements could consist of basic building blocks, which upon evolutionary selection result in functional elements with different properties. Although RNA-binding proteins (RBPs) perform a crucial role in the assembly of ribonucleoprotein complexes, the versatility and plasticity of RNA molecules, together with their high flexibility and dynamism, determines formation of macromolecular complexes in response to different signals. These properties rely on the presence of short RNA motifs, which operate as modular entities, and suggest that decomposition of IRES elements in short modules could help to understand the different mechanisms driven by these regulatory elements. Here we will review evidence suggesting that model IRES elements consist of the combination of short modules, providing sites of interaction for ribosome subunits, eIFs and RBPs, with implications for definition of criteria to identify novel IRES-like elements genome wide.
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Affiliation(s)
- Gloria Lozano
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Nicolás Cabrera 1, 28049 Madrid, Spain
| | - Rosario Francisco-Velilla
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Nicolás Cabrera 1, 28049 Madrid, Spain
| | - Encarnacion Martinez-Salas
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Nicolás Cabrera 1, 28049 Madrid, Spain
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18
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Martinez-Salas E, Francisco-Velilla R, Fernandez-Chamorro J, Embarek AM. Insights into Structural and Mechanistic Features of Viral IRES Elements. Front Microbiol 2018; 8:2629. [PMID: 29354113 PMCID: PMC5759354 DOI: 10.3389/fmicb.2017.02629] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 12/15/2017] [Indexed: 01/19/2023] Open
Abstract
Internal ribosome entry site (IRES) elements are cis-acting RNA regions that promote internal initiation of protein synthesis using cap-independent mechanisms. However, distinct types of IRES elements present in the genome of various RNA viruses perform the same function despite lacking conservation of sequence and secondary RNA structure. Likewise, IRES elements differ in host factor requirement to recruit the ribosomal subunits. In spite of this diversity, evolutionarily conserved motifs in each family of RNA viruses preserve sequences impacting on RNA structure and RNA–protein interactions important for IRES activity. Indeed, IRES elements adopting remarkable different structural organizations contain RNA structural motifs that play an essential role in recruiting ribosomes, initiation factors and/or RNA-binding proteins using different mechanisms. Therefore, given that a universal IRES motif remains elusive, it is critical to understand how diverse structural motifs deliver functions relevant for IRES activity. This will be useful for understanding the molecular mechanisms beyond cap-independent translation, as well as the evolutionary history of these regulatory elements. Moreover, it could improve the accuracy to predict IRES-like motifs hidden in genome sequences. This review summarizes recent advances on the diversity and biological relevance of RNA structural motifs for viral IRES elements.
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Affiliation(s)
- Encarnacion Martinez-Salas
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas - Universidad Autónoma de Madrid, Madrid, Spain
| | - Rosario Francisco-Velilla
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas - Universidad Autónoma de Madrid, Madrid, Spain
| | - Javier Fernandez-Chamorro
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas - Universidad Autónoma de Madrid, Madrid, Spain
| | - Azman M Embarek
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas - Universidad Autónoma de Madrid, Madrid, Spain
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19
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Diaz-Toledano R, Lozano G, Martinez-Salas E. In-cell SHAPE uncovers dynamic interactions between the untranslated regions of the foot-and-mouth disease virus RNA. Nucleic Acids Res 2017; 45:1416-1432. [PMID: 28180318 PMCID: PMC5388415 DOI: 10.1093/nar/gkw795] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 08/26/2016] [Accepted: 08/29/2016] [Indexed: 12/14/2022] Open
Abstract
The genome of RNA viruses folds into 3D structures that include long-range RNA–RNA interactions relevant to control critical steps of the viral cycle. In particular, initiation of translation driven by the IRES element of foot-and-mouth disease virus is stimulated by the 3΄UTR. Here we sought to investigate the RNA local flexibility of the IRES element and the 3΄UTR in living cells. The SHAPE reactivity observed in vivo showed statistically significant differences compared to the free RNA, revealing protected or exposed positions within the IRES and the 3΄UTR. Importantly, the IRES local flexibility was modified in the presence of the 3΄UTR, showing significant protections at residues upstream from the functional start codon. Conversely, presence of the IRES element in cis altered the 3΄UTR local flexibility leading to an overall enhanced reactivity. Unlike the reactivity changes observed in the IRES element, the SHAPE differences of the 3΄UTR were large but not statistically significant, suggesting multiple dynamic RNA interactions. These results were supported by covariation analysis, which predicted IRES-3΄UTR conserved helices in agreement with the protections observed by SHAPE probing. Mutational analysis suggested that disruption of one of these interactions could be compensated by alternative base pairings, providing direct evidences for dynamic long-range interactions between these distant elements of the viral genome.
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Affiliation(s)
- Rosa Diaz-Toledano
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas - Universidad Autónoma de Madrid, Nicolas Cabrera 1, Madrid, Spain
| | - Gloria Lozano
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas - Universidad Autónoma de Madrid, Nicolas Cabrera 1, Madrid, Spain
| | - Encarnacion Martinez-Salas
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas - Universidad Autónoma de Madrid, Nicolas Cabrera 1, Madrid, Spain
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20
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Garcia-Martin JA, Dotu I, Fernandez-Chamorro J, Lozano G, Ramajo J, Martinez-Salas E, Clote P. RNAiFold2T: Constraint Programming design of thermo-IRES switches. Bioinformatics 2016; 32:i360-i368. [PMID: 27307638 PMCID: PMC4908349 DOI: 10.1093/bioinformatics/btw265] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
MOTIVATION RNA thermometers (RNATs) are cis-regulatory elements that change secondary structure upon temperature shift. Often involved in the regulation of heat shock, cold shock and virulence genes, RNATs constitute an interesting potential resource in synthetic biology, where engineered RNATs could prove to be useful tools in biosensors and conditional gene regulation. RESULTS Solving the 2-temperature inverse folding problem is critical for RNAT engineering. Here we introduce RNAiFold2T, the first Constraint Programming (CP) and Large Neighborhood Search (LNS) algorithms to solve this problem. Benchmarking tests of RNAiFold2T against existent programs (adaptive walk and genetic algorithm) inverse folding show that our software generates two orders of magnitude more solutions, thus allowing ample exploration of the space of solutions. Subsequently, solutions can be prioritized by computing various measures, including probability of target structure in the ensemble, melting temperature, etc. Using this strategy, we rationally designed two thermosensor internal ribosome entry site (thermo-IRES) elements, whose normalized cap-independent translation efficiency is approximately 50% greater at 42 °C than 30 °C, when tested in reticulocyte lysates. Translation efficiency is lower than that of the wild-type IRES element, which on the other hand is fully resistant to temperature shift-up. This appears to be the first purely computational design of functional RNA thermoswitches, and certainly the first purely computational design of functional thermo-IRES elements. AVAILABILITY RNAiFold2T is publicly available as part of the new release RNAiFold3.0 at https://github.com/clotelab/RNAiFold and http://bioinformatics.bc.edu/clotelab/RNAiFold, which latter has a web server as well. The software is written in C ++ and uses OR-Tools CP search engine. CONTACT clote@bc.edu SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
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Affiliation(s)
| | - Ivan Dotu
- Department of Experimental and Health Sciences, Research Programme on Biomedical Informatics (GRIB), Universitat Pompeu Fabra. Dr. Aiguader 88, Barcelona, Spain
| | - Javier Fernandez-Chamorro
- Centro de Biologia Molecular Severo Ochoa, Consejo Superior de Investigaciones Cientificas-Universidad Autonoma de Madrid, 28049 Madrid, Spain
| | - Gloria Lozano
- Centro de Biologia Molecular Severo Ochoa, Consejo Superior de Investigaciones Cientificas-Universidad Autonoma de Madrid, 28049 Madrid, Spain
| | - Jorge Ramajo
- Centro de Biologia Molecular Severo Ochoa, Consejo Superior de Investigaciones Cientificas-Universidad Autonoma de Madrid, 28049 Madrid, Spain
| | - Encarnacion Martinez-Salas
- Centro de Biologia Molecular Severo Ochoa, Consejo Superior de Investigaciones Cientificas-Universidad Autonoma de Madrid, 28049 Madrid, Spain
| | - Peter Clote
- Biology Department, Boston College, Chestnut Hill, MA 02467, USA
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21
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Designing synthetic RNAs to determine the relevance of structural motifs in picornavirus IRES elements. Sci Rep 2016; 6:24243. [PMID: 27053355 PMCID: PMC4823658 DOI: 10.1038/srep24243] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 03/23/2016] [Indexed: 12/22/2022] Open
Abstract
The function of Internal Ribosome Entry Site (IRES) elements is intimately linked to their RNA structure. Viral IRES elements are organized in modular domains consisting of one or more stem-loops that harbor conserved RNA motifs critical for internal initiation of translation. A conserved motif is the pyrimidine-tract located upstream of the functional initiation codon in type I and II picornavirus IRES. By computationally designing synthetic RNAs to fold into a structure that sequesters the polypyrimidine tract in a hairpin, we establish a correlation between predicted inaccessibility of the pyrimidine tract and IRES activity, as determined in both in vitro and in vivo systems. Our data supports the hypothesis that structural sequestration of the pyrimidine-tract within a stable hairpin inactivates IRES activity, since the stronger the stability of the hairpin the higher the inhibition of protein synthesis. Destabilization of the stem-loop immediately upstream of the pyrimidine-tract also decreases IRES activity. Our work introduces a hybrid computational/experimental method to determine the importance of structural motifs for biological function. Specifically, we show the feasibility of using the software RNAiFold to design synthetic RNAs with particular sequence and structural motifs that permit subsequent experimental determination of the importance of such motifs for biological function.
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22
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Lozano G, Jimenez-Aparicio R, Herrero S, Martinez-Salas E. Fingerprinting the junctions of RNA structure by an open-paddlewheel diruthenium compound. RNA (NEW YORK, N.Y.) 2016; 22:330-8. [PMID: 26759454 PMCID: PMC4748811 DOI: 10.1261/rna.054353.115] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Accepted: 12/05/2015] [Indexed: 05/17/2023]
Abstract
RNA function is determined by its structural organization. The RNA structure consists of the combination of distinct secondary structure motifs connected by junctions that play an essential role in RNA folding. Selective 2'-hydroxyl acylation analyzed by primer extension (SHAPE) probing is an established methodology to analyze the secondary structure of long RNA molecules in solution, which provides accurate data about unpaired nucleotides. However, the residues located at the junctions of RNA structures usually remain undetected. Here we report an RNA probing method based on the use of a novel open-paddlewheel diruthenium (OPW-Ru) compound [Ru2Cl2(µ-DPhF)3(DMSO)] (DPhF = N,N'-diphenylformamidinate). This compound has four potential coordination sites in a singular disposition to establish covalent bonds with substrates. As a proof of concept, we have analyzed the reactivity of OPW-Ru toward RNA using two viral internal ribosome entry site (IRES) elements whose function depends on the structural organization of the molecule. Our study suggests that the compound OPW-Ru preferentially attacks at positions located one or two nucleotides away from junctions or bulges of the RNA structure. The OPW-Ru fingerprinting data differ from that obtained by other chemical reagents and provides new information about RNA structure features.
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Affiliation(s)
- Gloria Lozano
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Madrid 28049, Spain
| | - Reyes Jimenez-Aparicio
- Departamento de Química Inorgánica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, Madrid 28040, Spain
| | - Santiago Herrero
- Departamento de Química Inorgánica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, Madrid 28040, Spain
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23
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Weingarten-Gabbay S, Elias-Kirma S, Nir R, Gritsenko AA, Stern-Ginossar N, Yakhini Z, Weinberger A, Segal E. Comparative genetics. Systematic discovery of cap-independent translation sequences in human and viral genomes. Science 2016; 351:351/6270/aad4939. [PMID: 26816383 DOI: 10.1126/science.aad4939] [Citation(s) in RCA: 211] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2015] [Accepted: 11/11/2015] [Indexed: 12/12/2022]
Abstract
To investigate gene specificity at the level of translation in both the human genome and viruses, we devised a high-throughput bicistronic assay to quantify cap-independent translation. We uncovered thousands of novel cap-independent translation sequences, and we provide insights on the landscape of translational regulation in both humans and viruses. We find extensive translational elements in the 3' untranslated region of human transcripts and the polyprotein region of uncapped RNA viruses. Through the characterization of regulatory elements underlying cap-independent translation activity, we identify potential mechanisms of secondary structure, short sequence motif, and base pairing with the 18S ribosomal RNA (rRNA). Furthermore, we systematically map the 18S rRNA regions for which reverse complementarity enhances translation. Thus, we make available insights into the mechanisms of translational control in humans and viruses.
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Affiliation(s)
- Shira Weingarten-Gabbay
- Department of Computer Science and Applied Mathematics, Weizmann Institute of Science, Rehovot 76100, Israel. Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Shani Elias-Kirma
- Department of Computer Science and Applied Mathematics, Weizmann Institute of Science, Rehovot 76100, Israel. Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Ronit Nir
- Department of Computer Science and Applied Mathematics, Weizmann Institute of Science, Rehovot 76100, Israel. Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Alexey A Gritsenko
- The Delft Bioinformatics Laboratory, Department of Intelligent Systems, Delft University of Technology, Delft, Netherlands. Platform Green Synthetic Biology, Delft, Netherlands. Kluyver Centre for Genomics of Industrial Fermentation, Delft, Netherlands
| | - Noam Stern-Ginossar
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Zohar Yakhini
- Department of Computer Science, Technion, Haifa, Israel. Agilent Laboratories, Tel-Aviv, Israel
| | - Adina Weinberger
- Department of Computer Science and Applied Mathematics, Weizmann Institute of Science, Rehovot 76100, Israel. Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Eran Segal
- Department of Computer Science and Applied Mathematics, Weizmann Institute of Science, Rehovot 76100, Israel. Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100, Israel.
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24
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Lozano G, Fernandez N, Martinez-Salas E. Modeling Three-Dimensional Structural Motifs of Viral IRES. J Mol Biol 2016; 428:767-776. [PMID: 26778619 DOI: 10.1016/j.jmb.2016.01.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 01/08/2016] [Accepted: 01/08/2016] [Indexed: 01/23/2023]
Abstract
RNA virus genomes are reservoirs of a wide diversity of RNA structural elements. In particular, specific regions of the viral genome have evolved to adopt specialized three-dimensional (3D) structures, which can act in concert with host factors and/or viral proteins to recruit the translation machinery on viral RNA using a mechanism that is independent on the 5' end. This strategy relies on cis-acting RNA sequences designated as internal ribosome entry site (IRES) elements. IRES elements that are found in the genome of different groups of RNA viruses perform the same function despite differing in primary sequence and secondary RNA structure and host factor requirement to recruit the translation machinery internally. Evolutionarily conserved motifs tend to preserve sequences in each group of RNA viruses impacting on RNA structure and RNA-protein interactions important for IRES function. However, due to the lack of sequence homology among genetically distant IRES elements, accurate modeling of 3D IRES structure is currently a challenging task. In addition, as a universal RNA motif unique to IRES elements has not been found, a better understanding of viral IRES structural motifs could greatly assist in the detection of IRES-like motifs hidden in genome sequences. The focus of this review is to describe recent advances in modeling viral IRES tertiary structural motifs and also novel approaches to detect sequences potentially folding as IRES-like motifs.
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Affiliation(s)
- Gloria Lozano
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas Universidad Autónoma de Madrid, Nicolas Cabrera 1, 28049 Madrid, Spain
| | - Noemi Fernandez
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas Universidad Autónoma de Madrid, Nicolas Cabrera 1, 28049 Madrid, Spain
| | - Encarnacion Martinez-Salas
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas Universidad Autónoma de Madrid, Nicolas Cabrera 1, 28049 Madrid, Spain.
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