1
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Zhou Y, Jiang Y, Chen SJ. SPRank─A Knowledge-Based Scoring Function for RNA-Ligand Pose Prediction and Virtual Screening. J Chem Theory Comput 2024. [PMID: 39150889 DOI: 10.1021/acs.jctc.4c00681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/18/2024]
Abstract
The growing interest in RNA-targeted drugs underscores the need for computational modeling of interactions between RNA molecules and small compounds. Having a reliable scoring function for RNA-ligand interactions is essential for effective computational drug screening. An ideal scoring function should not only predict the native pose for ligand binding but also rank the affinity of the binding for different ligands. However, existing scoring functions are primarily designed to predict the native binding modes for a given RNA-ligand pair and have not been thoroughly assessed for virtual screening purposes. In this paper, we introduce SPRank, a combination of machine-learning and knowledge-based scoring functions developed through a weighted iterative approach, specifically designed to tackle both binding mode prediction and virtual screening challenges. Our approach incorporates third-party docking software, such as rDock and AutoDock Vina, to sample flexible ligands against an ensemble of RNA structures, capturing the conformational flexibility of both the RNA and the ligand. Through rigorous testing, SPRank demonstrates improved performance compared to the tested scoring functions across four test sets comprising 122, 42, 55, and 71 nucleic acid-ligand complexes. Furthermore, SPRank exhibits improved performance in virtual screening tests targeting the HIV-1 TAR ensemble, which highlights its advantage in drug discovery. These results underscore the advantages of SPRank as a potentially promising tool for the RNA-targeted drug design. The source code of SPRank and the data sets are freely accessible at https://github.com/Vfold-RNA/SPRank.
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Affiliation(s)
- Yuanzhe Zhou
- Department of Physics and Astronomy, University of Missouri-Columbia, Columbia, Missouri 65211-7010, United States
| | - Yangwei Jiang
- Department of Physics and Astronomy, University of Missouri-Columbia, Columbia, Missouri 65211-7010, United States
| | - Shi-Jie Chen
- Department of Physics and Astronomy, Department of Biochemistry, Institute of Data Sciences and Informatics, University of Missouri-Columbia, Columbia, Missouri 65211-7010, United States
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2
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Dodaro A, Pavan M, Menin S, Salmaso V, Sturlese M, Moro S. Thermal titration molecular dynamics (TTMD): shedding light on the stability of RNA-small molecule complexes. Front Mol Biosci 2023; 10:1294543. [PMID: 38028536 PMCID: PMC10679717 DOI: 10.3389/fmolb.2023.1294543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 10/20/2023] [Indexed: 12/01/2023] Open
Abstract
Ribonucleic acids are gradually becoming relevant players among putative drug targets, thanks to the increasing amount of structural data exploitable for the rational design of selective and potent binders that can modulate their activity. Mainly, this information allows employing different computational techniques for predicting how well would a ribonucleic-targeting agent fit within the active site of its target macromolecule. Due to some intrinsic peculiarities of complexes involving nucleic acids, such as structural plasticity, surface charge distribution, and solvent-mediated interactions, the application of routinely adopted methodologies like molecular docking is challenged by scoring inaccuracies, while more physically rigorous methods such as molecular dynamics require long simulation times which hamper their conformational sampling capabilities. In the present work, we present the first application of Thermal Titration Molecular Dynamics (TTMD), a recently developed method for the qualitative estimation of unbinding kinetics, to characterize RNA-ligand complexes. In this article, we explored its applicability as a post-docking refinement tool on RNA in complex with small molecules, highlighting the capability of this method to identify the native binding mode among a set of decoys across various pharmaceutically relevant test cases.
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Affiliation(s)
| | | | | | | | | | - Stefano Moro
- Molecular Modeling Section (MMS), Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Padova, Italy
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3
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Abstract
Although fragment-based drug discovery (FBDD) has been successfully implemented and well-explored for protein targets, its feasibility for RNA targets is emerging. Despite the challenges associated with the selective targeting of RNA, efforts to integrate known methods of RNA binder discovery with fragment-based approaches have been fruitful, as a few bioactive ligands have been identified. Here, we review various fragment-based approaches implemented for RNA targets and provide insights into experimental design and outcomes to guide future work in the area. Indeed, investigations surrounding the molecular recognition of RNA by fragments address rather important questions such as the limits of molecular weight that confer selective binding and the physicochemical properties favorable for RNA binding and bioactivity.
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Affiliation(s)
- Blessy M. Suresh
- UF Scripps Biomedical Research & The Scripps Research Institute, Department of Chemistry, 130 Scripps Way, Jupiter, Florida 33458, United States
| | - Amirhossein Taghavi
- UF Scripps Biomedical Research & The Scripps Research Institute, Department of Chemistry, 130 Scripps Way, Jupiter, Florida 33458, United States
| | - Jessica L. Childs-Disney
- UF Scripps Biomedical Research & The Scripps Research Institute, Department of Chemistry, 130 Scripps Way, Jupiter, Florida 33458, United States
| | - Matthew D. Disney
- UF Scripps Biomedical Research & The Scripps Research Institute, Department of Chemistry, 130 Scripps Way, Jupiter, Florida 33458, United States
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4
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Koehn JT, Felder S, Weeks KM. Innovations in targeting RNA by fragment-based ligand discovery. Curr Opin Struct Biol 2023; 79:102550. [PMID: 36863268 PMCID: PMC10023403 DOI: 10.1016/j.sbi.2023.102550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Revised: 01/21/2023] [Accepted: 01/23/2023] [Indexed: 03/04/2023]
Abstract
A subset of functional regions within large RNAs fold into complex structures able to bind small-molecule ligands with high affinity and specificity. Fragment-based ligand discovery (FBLD) offers notable opportunities for discovery and design of potent small molecules that bind pockets in RNA. Here we share an integrated analysis of recent innovations in FBLD, emphasizing opportunities resulting from fragment elaboration via both linking and growing. Analysis of elaborated fragments emphasizes that high-quality interactions form with complex tertiary structures in RNA. FBLD-inspired small molecules have been shown to modulate RNA functions by competitively inhibiting protein binding and by selectively stabilizing dynamic RNA states. FBLD is creating a foundation to interrogate the relatively unknown structural space for RNA ligands and for discovery of RNA-targeted therapeutics.
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Affiliation(s)
- Jordan T Koehn
- Department of Chemistry, University of North Carolina, Chapel Hill NC 27599-3290, USA
| | - Simon Felder
- 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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5
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Morishita EC. Discovery of RNA-targeted small molecules through the merging of experimental and computational technologies. Expert Opin Drug Discov 2023; 18:207-226. [PMID: 36322542 DOI: 10.1080/17460441.2022.2134852] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION The field of RNA-targeted small molecules is rapidly evolving, owing to the advances in experimental and computational technologies. With the identification of several bioactive small molecules that target RNA, including the FDA-approved risdiplam, the biopharmaceutical industry is gaining confidence in the field. This review, based on the literature obtained from PubMed, aims to disseminate information about the various technologies developed for targeting RNA with small molecules and propose areas for improvement to develop drugs more efficiently, particularly those linked to diseases with unmet medical needs. AREAS COVERED The technologies for the identification of RNA targets, screening of chemical libraries against RNA, assessing the bioactivity and target engagement of the hit compounds, structure determination, and hit-to-lead optimization are reviewed. Along with the description of the technologies, their strengths, limitations, and examples of how they can impact drug discovery are provided. EXPERT OPINION Many existing technologies employed for protein targets have been repurposed for use in the discovery of RNA-targeted small molecules. In addition, technologies tailored for RNA targets have been developed. Nevertheless, more improvements are necessary, such as artificial intelligence to dissect important RNA structures and RNA-small-molecule interactions and more powerful chemical probing and structure prediction techniques.
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6
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Szczesniak I, Baliga-Gil A, Jarmolowicz A, Soszynska-Jozwiak M, Kierzek E. Structural and Functional RNA Motifs of SARS-CoV-2 and Influenza A Virus as a Target of Viral Inhibitors. Int J Mol Sci 2023; 24:ijms24021232. [PMID: 36674746 PMCID: PMC9860923 DOI: 10.3390/ijms24021232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 12/28/2022] [Accepted: 12/29/2022] [Indexed: 01/11/2023] Open
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the COVID-19 pandemic, whereas the influenza A virus (IAV) causes seasonal epidemics and occasional pandemics. Both viruses lead to widespread infection and death. SARS-CoV-2 and the influenza virus are RNA viruses. The SARS-CoV-2 genome is an approximately 30 kb, positive sense, 5' capped single-stranded RNA molecule. The influenza A virus genome possesses eight single-stranded negative-sense segments. The RNA secondary structure in the untranslated and coding regions is crucial in the viral replication cycle. The secondary structure within the RNA of SARS-CoV-2 and the influenza virus has been intensively studied. Because the whole of the SARS-CoV-2 and influenza virus replication cycles are dependent on RNA with no DNA intermediate, the RNA is a natural and promising target for the development of inhibitors. There are a lot of RNA-targeting strategies for regulating pathogenic RNA, such as small interfering RNA for RNA interference, antisense oligonucleotides, catalytic nucleic acids, and small molecules. In this review, we summarized the knowledge about the inhibition of SARS-CoV-2 and influenza A virus propagation by targeting their RNA secondary structure.
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7
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Suresh BM, Akahori Y, Taghavi A, Crynen G, Gibaut QMR, Li Y, Disney MD. Low-Molecular Weight Small Molecules Can Potently Bind RNA and Affect Oncogenic Pathways in Cells. J Am Chem Soc 2022; 144:20815-20824. [PMID: 36322830 PMCID: PMC9930674 DOI: 10.1021/jacs.2c08770] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
RNA is challenging to target with bioactive small molecules, particularly those of low molecular weight that bind with sufficient affinity and specificity. In this report, we developed a platform to address this challenge, affording a novel bioactive interaction. An RNA-focused small-molecule fragment collection (n = 2500) was constructed by analyzing features in all publicly reported compounds that bind RNA, the largest collection of RNA-focused fragments to date. The RNA-binding landscape for each fragment was studied by using a library-versus-library selection with an RNA library displaying a discrete structural element, probing over 12.8 million interactions, the greatest number of interactions between fragments and biomolecules probed experimentally. Mining of this dataset across the human transcriptome defined a drug-like fragment that potently and specifically targeted the microRNA-372 hairpin precursor, inhibiting its processing into the mature, functional microRNA and alleviating invasive and proliferative oncogenic phenotypes in gastric cancer cells. Importantly, this fragment has favorable properties, including an affinity for the RNA target of 300 ± 130 nM, a molecular weight of 273 Da, and quantitative estimate of drug-likeness (QED) score of 0.8. (For comparison, the mean QED of oral medicines is 0.6 ± 0.2). Thus, these studies demonstrate that a low-molecular weight, fragment-like compound can specifically and potently modulate RNA targets.
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Affiliation(s)
- Blessy M. Suresh
- Department of Chemistry, The Scripps Research Institute & UF Scripps Biomedical Research, 130 Scripps Way, Jupiter, FL 33458, United States
| | - Yoshihiro Akahori
- Department of Chemistry, The Scripps Research Institute & UF Scripps Biomedical Research, 130 Scripps Way, Jupiter, FL 33458, United States
| | - Amirhossein Taghavi
- Department of Chemistry, The Scripps Research Institute & UF Scripps Biomedical Research, 130 Scripps Way, Jupiter, FL 33458, United States
| | - Gogce Crynen
- Bioinformatics and Statistics Core, The Scripps Research Institute & UF Scripps Biomedical Research, 130 Scripps Way, Jupiter, FL 33458, United States
| | - Quentin M. R. Gibaut
- Department of Chemistry, The Scripps Research Institute & UF Scripps Biomedical Research, 130 Scripps Way, Jupiter, FL 33458, United States
| | - Yue Li
- Department of Chemistry, The Scripps Research Institute & UF Scripps Biomedical Research, 130 Scripps Way, Jupiter, FL 33458, United States
| | - Matthew D. Disney
- Department of Chemistry, The Scripps Research Institute & UF Scripps Biomedical Research, 130 Scripps Way, Jupiter, FL 33458, United States
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8
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Kognole AA, Hazel A, MacKerell AD. SILCS-RNA: Toward a Structure-Based Drug Design Approach for Targeting RNAs with Small Molecules. J Chem Theory Comput 2022; 18:5672-5691. [PMID: 35913731 PMCID: PMC9474704 DOI: 10.1021/acs.jctc.2c00381] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
RNA molecules can act as potential drug targets in different diseases, as their dysregulated expression or misfolding can alter various cellular processes. Noncoding RNAs account for ∼70% of the human genome, and these molecules can have complex tertiary structures that present a great opportunity for targeting by small molecules. In the present study, the site identification by ligand competitive saturation (SILCS) computational approach is extended to target RNA, termed SILCS-RNA. Extensions to the method include an enhanced oscillating excess chemical potential protocol for the grand canonical Monte Carlo calculations and individual simulations of the neutral and charged solutes from which the SILCS functional group affinity maps (FragMaps) are calculated for subsequent binding site identification and docking calculations. The method is developed and evaluated against seven RNA targets and their reported small molecule ligands. SILCS-RNA provides a detailed characterization of the functional group affinity pattern in the small molecule binding sites, recapitulating the types of functional groups present in the ligands. The developed method is also shown to be useful for identification of new potential binding sites and identifying ligand moieties that contribute to binding, granular information that can facilitate ligand design. However, limitations in the method are evident including the ability to map the regions of binding sites occupied by ligand phosphate moieties and to fully account for the wide range of conformational heterogeneity in RNA associated with binding of different small molecules, emphasizing inherent challenges associated with applying computer-aided drug design methods to RNA. While limitations are present, the current study indicates how the SILCS-RNA approach may enhance drug discovery efforts targeting RNAs with small molecules.
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Affiliation(s)
- Abhishek A Kognole
- Computer Aided Drug Design Center, Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland Baltimore, Baltimore, Maryland 21201, United States
| | - Anthony Hazel
- Computer Aided Drug Design Center, Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland Baltimore, Baltimore, Maryland 21201, United States
| | - Alexander D MacKerell
- Computer Aided Drug Design Center, Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland Baltimore, Baltimore, Maryland 21201, United States
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9
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Sato Y, Miura H, Tanabe T, Okeke CU, Kikuchi A, Nishizawa S. Fluorescence Sensing of the Panhandle Structure of the Influenza A Virus RNA Promoter by Thiazole Orange Base Surrogate-Carrying Peptide Nucleic Acid Conjugated with Small Molecule. Anal Chem 2022; 94:7814-7822. [PMID: 35604144 DOI: 10.1021/acs.analchem.1c05488] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We have developed a new class of triplex-forming peptide nucleic acid (PNA)-based fluorogenic probes for sensing of the panhandle structure of the influenza A virus (IAV) RNA promoter region. Here, a small molecule (DPQ) capable of selectively binding to the internal loop structure was conjugated with triplex-forming forced intercalation of the thiazole orange (tFIT) probe with natural PNA nucleobases. The resulting conjugate, tFIT-DPQ, showed a significant light-up response (83-fold) upon strong (Kd = 107 nM) and structure-selective binding to the IAV RNA promoter region under physiological conditions (pH 7.0, 100 mM NaCl). We demonstrated the conjugation of these two units through the suitable spacer was key to show useful binding and fluorogenic signaling functions. tFIT-DPQ facilitated the sensitive and selective detection of IAV RNA based on its binding to the promoter region. Furthermore, we found that tFIT-DPQ could work as a sensitive indicator for screening of test compounds targeting the IAV RNA promoter region in the fluorescence indicator displacement assay.
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Affiliation(s)
- Yusuke Sato
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan
| | - Hiromasa Miura
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan
| | - Takaaki Tanabe
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan
| | - Chioma Uche Okeke
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan
| | - Akiko Kikuchi
- Department of Kampo and Integrative Medicine, Graduate School of Medicine, Tohoku University, Sendai 980-8575, Japan
| | - Seiichi Nishizawa
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan
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10
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Zhou Y, Jiang Y, Chen SJ. RNA-ligand molecular docking: advances and challenges. WILEY INTERDISCIPLINARY REVIEWS. COMPUTATIONAL MOLECULAR SCIENCE 2022; 12:e1571. [PMID: 37293430 PMCID: PMC10250017 DOI: 10.1002/wcms.1571] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 07/20/2021] [Indexed: 12/16/2022]
Abstract
With rapid advances in computer algorithms and hardware, fast and accurate virtual screening has led to a drastic acceleration in selecting potent small molecules as drug candidates. Computational modeling of RNA-small molecule interactions has become an indispensable tool for RNA-targeted drug discovery. The current models for RNA-ligand binding have mainly focused on the docking-and-scoring method. Accurate docking and scoring should tackle four crucial problems: (1) conformational flexibility of ligand, (2) conformational flexibility of RNA, (3) efficient sampling of binding sites and binding poses, and (4) accurate scoring of different binding modes. Moreover, compared with the problem of protein-ligand docking, predicting ligand binding to RNA, a negatively charged polymer, is further complicated by additional effects such as metal ion effects. Thermodynamic models based on physics-based and knowledge-based scoring functions have shown highly encouraging success in predicting ligand binding poses and binding affinities. Recently, kinetic models for ligand binding have further suggested that including dissociation kinetics (residence time) in ligand docking would result in improved performance in estimating in vivo drug efficacy. More recently, the rise of deep-learning approaches has led to new tools for predicting RNA-small molecule binding. In this review, we present an overview of the recently developed computational methods for RNA-ligand docking and their advantages and disadvantages.
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Affiliation(s)
- Yuanzhe Zhou
- Department of Physics and Astronomy, Department of Biochemistry, Institute of Data Sciences and Informatics, University of Missouri, Columbia, MO 65211-7010, USA
| | - Yangwei Jiang
- Department of Physics and Astronomy, Department of Biochemistry, Institute of Data Sciences and Informatics, University of Missouri, Columbia, MO 65211-7010, USA
| | - Shi-Jie Chen
- Department of Physics and Astronomy, Department of Biochemistry, Institute of Data Sciences and Informatics, University of Missouri, Columbia, MO 65211-7010, USA
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11
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Targeting Xist with compounds that disrupt RNA structure and X inactivation. Nature 2022; 604:160-166. [PMID: 35355011 DOI: 10.1038/s41586-022-04537-z] [Citation(s) in RCA: 51] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 02/08/2022] [Indexed: 12/13/2022]
Abstract
Although more than 98% of the human genome is non-coding1, nearly all of the drugs on the market target one of about 700 disease-related proteins. The historical reluctance to invest in non-coding RNA stems partly from requirements for drug targets to adopt a single stable conformation2. Most RNAs can adopt several conformations of similar stabilities. RNA structures also remain challenging to determine3. Nonetheless, an increasing number of diseases are now being attributed to non-coding RNA4 and the ability to target them would vastly expand the chemical space for drug development. Here we devise a screening strategy and identify small molecules that bind the non-coding RNA prototype Xist5. The X1 compound has drug-like properties and binds specifically the RepA motif6 of Xist in vitro and in vivo. Small-angle X-ray scattering analysis reveals that RepA can adopt multiple conformations but favours one structure in solution. X1 binding reduces the conformational space of RepA, displaces cognate interacting protein factors (PRC2 and SPEN), suppresses histone H3K27 trimethylation, and blocks initiation of X-chromosome inactivation. X1 inhibits cell differentiation and growth in a female-specific manner. Thus, RNA can be systematically targeted by drug-like compounds that disrupt RNA structure and epigenetic function.
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12
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Zhao R, Fu J, Zhu L, Chen Y, Liu B. Designing strategies of small-molecule compounds for modulating non-coding RNAs in cancer therapy. J Hematol Oncol 2022; 15:14. [PMID: 35123522 PMCID: PMC8817562 DOI: 10.1186/s13045-022-01230-6] [Citation(s) in RCA: 43] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 01/21/2022] [Indexed: 02/07/2023] Open
Abstract
Non-coding RNAs (ncRNAs) have been defined as a class of RNA molecules transcribed from the genome but not encoding proteins, such as microRNAs, long non-coding RNAs, Circular RNAs, and Piwi-interacting RNAs. Accumulating evidence has recently been revealing that ncRNAs become potential druggable targets for regulation of several small-molecule compounds, based on their complex spatial structures and biological functions in cancer therapy. Thus, in this review, we focus on summarizing some new emerging designing strategies, such as high-throughput screening approach, small-molecule microarray approach, structure-based designing approach, phenotypic screening approach, fragment-based designing approach, and pharmacological validation approach. Based on the above-mentioned approaches, a series of representative small-molecule compounds, including Bisphenol-A, Mitoxantrone and Enoxacin have been demonstrated to modulate or selectively target ncRNAs in different types of human cancers. Collectively, these inspiring findings would provide a clue on developing more novel avenues for pharmacological modulations of ncRNAs with small-molecule drugs for future cancer therapeutics.
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13
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Chen Q, Li Y, Lin C, Chen L, Luo H, Xia S, Liu C, Cheng X, Liu C, Li J, Dou D. OUP accepted manuscript. Nucleic Acids Res 2022; 50:e67. [PMID: 35288754 PMCID: PMC9262588 DOI: 10.1093/nar/gkac173] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 02/02/2022] [Accepted: 03/04/2022] [Indexed: 11/21/2022] Open
Abstract
DNA-encoded library (DEL) technology is a powerful tool for small molecule identification in drug discovery, yet the reported DEL selection strategies were applied primarily on protein targets in either purified form or in cellular context. To expand the application of this technology, we employed DEL selection on an RNA target HIV-1 TAR (trans-acting responsive region), but found that the majority of signals were resulted from false positive DNA–RNA binding. We thus developed an optimized selection strategy utilizing RNA patches and competitive elution to minimize unwanted DNA binding, followed by k-mer analysis and motif search to differentiate false positive signal. This optimized strategy resulted in a very clean background in a DEL selection against Escherichia coli FMN Riboswitch, and the enriched compounds were determined with double digit nanomolar binding affinity, as well as similar potency in functional FMN competition assay. These results demonstrated the feasibility of small molecule identification against RNA targets using DEL selection. The developed experimental and computational strategy provided a promising opportunity for RNA ligand screening and expanded the application of DEL selection to a much wider context in drug discovery.
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Affiliation(s)
| | | | | | - Liu Chen
- HitGen Inc., Shuangliu District, Chengdu, China
| | - Hao Luo
- HitGen Inc., Shuangliu District, Chengdu, China
| | - Shuai Xia
- HitGen Inc., Shuangliu District, Chengdu, China
| | - Chuan Liu
- HitGen Inc., Shuangliu District, Chengdu, China
| | | | | | - Jin Li
- HitGen Inc., Shuangliu District, Chengdu, China
| | - Dengfeng Dou
- To whom correspondence should be addressed. Tel: +86 28 85197385 8700;
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14
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NISHIZAWA S, LEE ETT, YOSHINO Y, YAJIMA S, ROKUGAWA M, SATO Y. Molecular Design of Fluorogenic Probes for Targeting rRNA: Indicator in FID Assay and Dye for Imaging of Nucleolar RNA in Living Cells. BUNSEKI KAGAKU 2021. [DOI: 10.2116/bunsekikagaku.70.703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Seiichi NISHIZAWA
- Department of Chemistry, Graduate School of Sciences, Tohoku University
| | | | - Yukina YOSHINO
- Department of Chemistry, Graduate School of Sciences, Tohoku University
| | - Sayaka YAJIMA
- Department of Chemistry, Graduate School of Sciences, Tohoku University
| | - Masafumi ROKUGAWA
- Department of Chemistry, Graduate School of Sciences, Tohoku University
| | - Yusuke SATO
- Department of Chemistry, Graduate School of Sciences, Tohoku University
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15
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Shortridge MD, Varani G. Efficient NMR Screening Approach to Discover Small Molecule Fragments Binding Structured RNA. ACS Med Chem Lett 2021; 12:1253-1260. [PMID: 34413954 DOI: 10.1021/acsmedchemlett.1c00109] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 07/07/2021] [Indexed: 01/27/2023] Open
Abstract
We describe a scalable nuclear magnetic resonance (NMR) screening approach to identify and prioritize small molecule fragments that bind to structured RNAs. This approach is target agnostic and, therefore, amenable to many RNA structures and libraries, and it provides initial hits for further synthetic elaboration and structure-based drug discovery efforts. We demonstrate the approach on the pre-miR-21 stem-loop, which is of significant interest in oncology and metabolic diseases. We screened the pre-miR-21 hairpin using a small (420 compounds) commercially available fragment library and identified 18 hits in the first round of triage screening. This was further refined to four fragments which passed all screening cascade filters. Among these four hits, a thiadiazole fragment was demonstrated to bind the Dicer cleavage site of pre-miR-21 by target-detected NMR experiments and through the observation of clear intermolecular NOEs.
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Affiliation(s)
- Matthew D. Shortridge
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Gabriele Varani
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
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16
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Lundquist KP, Panchal V, Gotfredsen CH, Brenk R, Clausen MH. Fragment-Based Drug Discovery for RNA Targets. ChemMedChem 2021; 16:2588-2603. [PMID: 34101375 DOI: 10.1002/cmdc.202100324] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Indexed: 12/26/2022]
Abstract
Rapid development within the fields of both fragment-based drug discovery (FBDD) and medicinal targeting of RNA provides possibilities for combining technologies and methods in novel ways. This review provides an overview of fragment-based screening (FBS) against RNA targets, including a discussion of the most recently used screening and hit validation methods such as NMR spectroscopy, X-ray crystallography, and virtual screening methods. A discussion of fragment library design based on research from small-molecule RNA binders provides an overview on both the currently limited guidelines within RNA-targeting fragment library design, and future possibilities. Finally, future perspectives are provided on screening and hit validation methods not yet used in combination with both fragment screening and RNA targets.
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Affiliation(s)
- Kasper P Lundquist
- Center for Nanomedicine and Theranostics, Department of Chemistry, Technical University of Denmark, Kemitorvet 207, 2800, Kgs. Lyngby, Denmark
| | - Vipul Panchal
- Department of Biomedicine, University of Bergen, Jonas Lies vei 91, 5020, Bergen, Norway
| | - Charlotte H Gotfredsen
- NMR Center ⋅ DTU, Department of Chemistry, Technical University of Denmark, Kemitorvet 207, 2800, Kgs. Lyngby, Denmark
| | - Ruth Brenk
- Department of Biomedicine, University of Bergen, Jonas Lies vei 91, 5020, Bergen, Norway
| | - Mads H Clausen
- Center for Nanomedicine and Theranostics, Department of Chemistry, Technical University of Denmark, Kemitorvet 207, 2800, Kgs. Lyngby, Denmark
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17
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Rekand IH, Brenk R. DrugPred_RNA-A Tool for Structure-Based Druggability Predictions for RNA Binding Sites. J Chem Inf Model 2021; 61:4068-4081. [PMID: 34286972 PMCID: PMC8389535 DOI: 10.1021/acs.jcim.1c00155] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
![]()
RNA is an emerging
target for drug discovery. However, like for
proteins, not all RNA binding sites are equally suited to be addressed
with conventional drug-like ligands. To this end, we have developed
the structure-based druggability predictor DrugPred_RNA to identify
druggable RNA binding sites. Due to the paucity of annotated RNA binding
sites, the predictor was trained on protein pockets, albeit using
only descriptors that can be calculated for both RNA and protein binding
sites. DrugPred_RNA performed well in discriminating druggable from
less druggable binding sites for the protein set and delivered predictions
for selected RNA binding sites that agreed with manual assignment.
In addition, most drug-like ligands contained in an RNA test set were
found in pockets predicted to be druggable, further adding confidence
to the performance of DrugPred_RNA. The method is robust against conformational
and sequence changes in the binding sites and can contribute to direct
drug discovery efforts for RNA targets.
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Affiliation(s)
- Illimar Hugo Rekand
- Department of Biomedicine, University of Bergen, Jonas Lies Vei, 5020 Bergen, Norway
| | - Ruth Brenk
- Department of Biomedicine, University of Bergen, Jonas Lies Vei, 5020 Bergen, Norway
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18
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Kelly ML, Chu CC, Shi H, Ganser LR, Bogerd HP, Huynh K, Hou Y, Cullen BR, Al-Hashimi HM. Understanding the characteristics of nonspecific binding of drug-like compounds to canonical stem-loop RNAs and their implications for functional cellular assays. RNA (NEW YORK, N.Y.) 2021; 27:12-26. [PMID: 33028652 PMCID: PMC7749633 DOI: 10.1261/rna.076257.120] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Accepted: 09/26/2020] [Indexed: 05/30/2023]
Abstract
Identifying small molecules that selectively bind an RNA target while discriminating against all other cellular RNAs is an important challenge in RNA-targeted drug discovery. Much effort has been directed toward identifying drug-like small molecules that minimize electrostatic and stacking interactions that lead to nonspecific binding of aminoglycosides and intercalators to many stem-loop RNAs. Many such compounds have been reported to bind RNAs and inhibit their cellular activities. However, target engagement and cellular selectivity assays are not routinely performed, and it is often unclear whether functional activity directly results from specific binding to the target RNA. Here, we examined the propensities of three drug-like compounds, previously shown to bind and inhibit the cellular activities of distinct stem-loop RNAs, to bind and inhibit the cellular activities of two unrelated HIV-1 stem-loop RNAs: the transactivation response element (TAR) and the rev response element stem IIB (RREIIB). All compounds bound TAR and RREIIB in vitro, and two inhibited TAR-dependent transactivation and RRE-dependent viral export in cell-based assays while also exhibiting off-target interactions consistent with nonspecific activity. A survey of X-ray and NMR structures of RNA-small molecule complexes revealed that aminoglycosides and drug-like molecules form hydrogen bonds with functional groups commonly accessible in canonical stem-loop RNA motifs, in contrast to ligands that specifically bind riboswitches. Our results demonstrate that drug-like molecules can nonspecifically bind stem-loop RNAs most likely through hydrogen bonding and electrostatic interactions and reinforce the importance of assaying for off-target interactions and RNA selectivity in vitro and in cells when assessing novel RNA-binders.
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Affiliation(s)
- Megan L Kelly
- Department of Biochemistry, Center for Virology, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Chia-Chieh Chu
- Department of Biochemistry, Center for Virology, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Honglue Shi
- Department of Chemistry, Center for Virology, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Laura R Ganser
- Department of Biochemistry, Center for Virology, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Hal P Bogerd
- Department of Molecular Genetics and Microbiology, Center for Virology, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Kelly Huynh
- Department of Biochemistry, Center for Virology, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Yuze Hou
- Department of Biochemistry, Center for Virology, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Bryan R Cullen
- Department of Molecular Genetics and Microbiology, Center for Virology, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Hashim M Al-Hashimi
- Department of Biochemistry, Center for Virology, Duke University Medical Center, Durham, North Carolina 27710, USA
- Department of Chemistry, Center for Virology, Duke University Medical Center, Durham, North Carolina 27710, USA
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19
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Yu AM, Choi YH, Tu MJ. RNA Drugs and RNA Targets for Small Molecules: Principles, Progress, and Challenges. Pharmacol Rev 2020; 72:862-898. [PMID: 32929000 PMCID: PMC7495341 DOI: 10.1124/pr.120.019554] [Citation(s) in RCA: 184] [Impact Index Per Article: 46.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
RNA-based therapies, including RNA molecules as drugs and RNA-targeted small molecules, offer unique opportunities to expand the range of therapeutic targets. Various forms of RNAs may be used to selectively act on proteins, transcripts, and genes that cannot be targeted by conventional small molecules or proteins. Although development of RNA drugs faces unparalleled challenges, many strategies have been developed to improve RNA metabolic stability and intracellular delivery. A number of RNA drugs have been approved for medical use, including aptamers (e.g., pegaptanib) that mechanistically act on protein target and small interfering RNAs (e.g., patisiran and givosiran) and antisense oligonucleotides (e.g., inotersen and golodirsen) that directly interfere with RNA targets. Furthermore, guide RNAs are essential components of novel gene editing modalities, and mRNA therapeutics are under development for protein replacement therapy or vaccination, including those against unprecedented severe acute respiratory syndrome coronavirus pandemic. Moreover, functional RNAs or RNA motifs are highly structured to form binding pockets or clefts that are accessible by small molecules. Many natural, semisynthetic, or synthetic antibiotics (e.g., aminoglycosides, tetracyclines, macrolides, oxazolidinones, and phenicols) can directly bind to ribosomal RNAs to achieve the inhibition of bacterial infections. Therefore, there is growing interest in developing RNA-targeted small-molecule drugs amenable to oral administration, and some (e.g., risdiplam and branaplam) have entered clinical trials. Here, we review the pharmacology of novel RNA drugs and RNA-targeted small-molecule medications, with a focus on recent progresses and strategies. Challenges in the development of novel druggable RNA entities and identification of viable RNA targets and selective small-molecule binders are discussed. SIGNIFICANCE STATEMENT: With the understanding of RNA functions and critical roles in diseases, as well as the development of RNA-related technologies, there is growing interest in developing novel RNA-based therapeutics. This comprehensive review presents pharmacology of both RNA drugs and RNA-targeted small-molecule medications, focusing on novel mechanisms of action, the most recent progress, and existing challenges.
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MESH Headings
- Aptamers, Nucleotide/pharmacology
- Aptamers, Nucleotide/therapeutic use
- Betacoronavirus
- COVID-19
- Chemistry Techniques, Analytical/methods
- Chemistry Techniques, Analytical/standards
- Clustered Regularly Interspaced Short Palindromic Repeats
- Coronavirus Infections/drug therapy
- Drug Delivery Systems/methods
- Drug Development/organization & administration
- Drug Discovery
- Humans
- MicroRNAs/pharmacology
- MicroRNAs/therapeutic use
- Oligonucleotides, Antisense/pharmacology
- Oligonucleotides, Antisense/therapeutic use
- Pandemics
- Pneumonia, Viral/drug therapy
- RNA/adverse effects
- RNA/drug effects
- RNA/pharmacology
- RNA, Antisense/pharmacology
- RNA, Antisense/therapeutic use
- RNA, Messenger/drug effects
- RNA, Messenger/pharmacology
- RNA, Ribosomal/drug effects
- RNA, Ribosomal/pharmacology
- RNA, Small Interfering/pharmacology
- RNA, Small Interfering/therapeutic use
- RNA, Viral/drug effects
- Ribonucleases/metabolism
- Riboswitch/drug effects
- SARS-CoV-2
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Affiliation(s)
- Ai-Ming Yu
- Department of Biochemistry and Molecular Medicine, UC Davis School of Medicine, Sacramento, California (A.-M.Y., Y.H.C., M.-J.T.) and College of Pharmacy and Integrated Research Institute for Drug Development, Dongguk University-Seoul, Goyang-si, Gyonggi-do, Republic of Korea (Y.H.C.)
| | - Young Hee Choi
- Department of Biochemistry and Molecular Medicine, UC Davis School of Medicine, Sacramento, California (A.-M.Y., Y.H.C., M.-J.T.) and College of Pharmacy and Integrated Research Institute for Drug Development, Dongguk University-Seoul, Goyang-si, Gyonggi-do, Republic of Korea (Y.H.C.)
| | - Mei-Juan Tu
- Department of Biochemistry and Molecular Medicine, UC Davis School of Medicine, Sacramento, California (A.-M.Y., Y.H.C., M.-J.T.) and College of Pharmacy and Integrated Research Institute for Drug Development, Dongguk University-Seoul, Goyang-si, Gyonggi-do, Republic of Korea (Y.H.C.)
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20
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Haniff HS, Knerr L, Chen JL, Disney MD, Lightfoot HL. Target-Directed Approaches for Screening Small Molecules against RNA Targets. SLAS DISCOVERY : ADVANCING LIFE SCIENCES R & D 2020; 25:869-894. [PMID: 32419578 PMCID: PMC7442623 DOI: 10.1177/2472555220922802] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
RNA molecules have a variety of cellular functions that can drive disease pathologies. They are without a doubt one of the most intriguing yet controversial small-molecule drug targets. The ability to widely target RNA with small molecules could be revolutionary, once the right tools, assays, and targets are selected, thereby defining which biomolecules are targetable and what constitutes drug-like small molecules. Indeed, approaches developed over the past 5-10 years have changed the face of small molecule-RNA targeting by addressing historic concerns regarding affinity, selectivity, and structural dynamics. Presently, selective RNA-protein complex stabilizing drugs such as branaplam and risdiplam are in clinical trials for the modulation of SMN2 splicing, compounds identified from phenotypic screens with serendipitous outcomes. Fully developing RNA as a druggable target will require a target engagement-driven approach, and evolving chemical collections will be important for the industrial development of this class of target. In this review we discuss target-directed approaches that can be used to identify RNA-binding compounds and the chemical knowledge we have today of small-molecule RNA binders.
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Affiliation(s)
- Hafeez S. Haniff
- Department of Chemistry, The Scripps Research Institute, Jupiter, FL, USA
| | - Laurent Knerr
- Medicinal Chemistry, Research and Early Development, Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Jonathan L. Chen
- Department of Chemistry, The Scripps Research Institute, Jupiter, FL, USA
| | - Matthew D. Disney
- Department of Chemistry, The Scripps Research Institute, Jupiter, FL, USA
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21
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Bissaro M, Sturlese M, Moro S. Exploring the RNA-Recognition Mechanism Using Supervised Molecular Dynamics (SuMD) Simulations: Toward a Rational Design for Ribonucleic-Targeting Molecules? Front Chem 2020; 8:107. [PMID: 32175307 PMCID: PMC7057144 DOI: 10.3389/fchem.2020.00107] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Accepted: 02/04/2020] [Indexed: 11/30/2022] Open
Abstract
Although proteins have represented the molecular target of choice in the development of new drug candidates, the pharmaceutical importance of ribonucleic acids has gradually been growing. The increasing availability of structural information has brought to light the existence of peculiar three-dimensional RNA arrangements, which can, contrary to initial expectations, be recognized and selectively modulated through small chemical entities or peptides. The application of classical computational methodologies, such as molecular docking, for the rational development of RNA-binding candidates is, however, complicated by the peculiarities characterizing these macromolecules, such as the marked conformational flexibility, the singular charges distribution, and the relevant role of solvent molecules. In this work, we have thus validated and extended the applicability domain of SuMD, an all-atoms molecular dynamics protocol that allows to accelerate the sampling of molecular recognition events on a nanosecond timescale, to ribonucleotide targets of pharmaceutical interest. In particular, we have proven the methodological ability by reproducing the binding mode of viral or prokaryotic ribonucleic complexes, as well as that of artificially engineered aptamers, with an impressive degree of accuracy.
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Affiliation(s)
- Maicol Bissaro
- Molecular Modeling Section, Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Padua, Italy
| | - Mattia Sturlese
- Molecular Modeling Section, Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Padua, Italy
| | - Stefano Moro
- Molecular Modeling Section, Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Padua, Italy
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22
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Chakraborty J, Kanungo A, Mahata T, Kumar K, Sharma G, Pal R, Ahammed KS, Patra D, Majhi B, Chakrabarti S, Das S, Dutta S. Quinoxaline derivatives disrupt the base stacking of hepatitis C virus-internal ribosome entry site RNA: reduce translation and replication. Chem Commun (Camb) 2019; 55:14027-14030. [PMID: 31690898 DOI: 10.1039/c9cc06531h] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
RNA-biased small molecules with a monoquinoxaline core target the L-shaped structure of subdomain IIa of Hepatitis C virus internal ribosome entry site (IRES) RNA in proximity to the Mg2+ binding site. The binding event leads to the destacking of RNA bases, resulting in the inhibition of IRES-mediated translation and HCV RNA replication.
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Affiliation(s)
- Jeet Chakraborty
- Organic and Medicinal Chemistry Division, CSIR-Indian Institute of Chemical Biology, 4 Raja S. C. Mullick Road, Kolkata 700032, West Bengal, India.
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23
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Sato Y, Aiba Y, Yajima S, Tanabe T, Higuchi K, Nishizawa S. Strong Binding and Off–On Signaling Functions of Deep‐Red Fluorescent TO‐PRO‐3 for Influenza A Virus RNA Promoter Region. Chembiochem 2019; 20:2752-2756. [DOI: 10.1002/cbic.201900331] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Indexed: 11/10/2022]
Affiliation(s)
- Yusuke Sato
- Department of ChemistryGraduate School of ScienceTohoku University Sendai 980-8578 Japan
| | - Yuri Aiba
- Department of ChemistryGraduate School of ScienceTohoku University Sendai 980-8578 Japan
| | - Sayaka Yajima
- Department of ChemistryGraduate School of ScienceTohoku University Sendai 980-8578 Japan
| | - Takaaki Tanabe
- Department of ChemistryGraduate School of ScienceTohoku University Sendai 980-8578 Japan
| | - Kei Higuchi
- Department of ChemistryGraduate School of ScienceTohoku University Sendai 980-8578 Japan
| | - Seiichi Nishizawa
- Department of ChemistryGraduate School of ScienceTohoku University Sendai 980-8578 Japan
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24
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Di Giorgio A, Duca M. Synthetic small-molecule RNA ligands: future prospects as therapeutic agents. MEDCHEMCOMM 2019; 10:1242-1255. [PMID: 31534649 PMCID: PMC6748380 DOI: 10.1039/c9md00195f] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Accepted: 04/30/2019] [Indexed: 12/17/2022]
Abstract
RNA is one of the most intriguing and promising biological targets for the discovery of innovative drugs in many pathologies and various biologically relevant RNAs that could serve as drug targets have already been identified. Among the most important ones, one can mention prokaryotic ribosomal RNA which is the target of several marketed antibiotics, viral RNAs or oncogenic microRNAs that are tightly involved in the development and progression of various cancers. Oligonucleotides are efficient and specific RNA targeting agents but suffer from poor pharmacodynamic and pharmacokinetic properties. For this reason, a number of synthetic small-molecule ligands have been identified and studied upon screening of chemical libraries or focused design of RNA binders. In this review, we report the most relevant examples of synthetic compounds bearing sufficient selectivity to envisage clinical studies and future therapeutic applications with a particular attention for the main strategies that can be undertaken toward the improvement of selectivity and biological activity.
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Affiliation(s)
- A Di Giorgio
- Université Côte d'Azur , CNRS , Institute of Chemistry of Nice (ICN) , Nice , France .
| | - M Duca
- Université Côte d'Azur , CNRS , Institute of Chemistry of Nice (ICN) , Nice , France .
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25
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Morgan BS, Forte JE, Hargrove AE. Insights into the development of chemical probes for RNA. Nucleic Acids Res 2019; 46:8025-8037. [PMID: 30102391 PMCID: PMC6144806 DOI: 10.1093/nar/gky718] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 07/27/2018] [Indexed: 12/18/2022] Open
Abstract
Over the past decade, the RNA revolution has revealed thousands of non-coding RNAs that are essential for cellular regulation and are misregulated in disease. While the development of methods and tools to study these RNAs has been challenging, the power and promise of small molecule chemical probes is increasingly recognized. To harness existing knowledge, we compiled a list of 116 ligands with reported activity against RNA targets in biological systems (R-BIND). In this survey, we examine the RNA targets, design and discovery strategies, and chemical probe characterization techniques of these ligands. We discuss the applicability of current tools to identify and evaluate RNA-targeted chemical probes, suggest criteria to assess the quality of RNA chemical probes and targets, and propose areas where new tools are particularly needed. We anticipate that this knowledge will expedite the discovery of RNA-targeted ligands and the next phase of the RNA revolution.
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Affiliation(s)
| | - Jordan E Forte
- Department of Chemistry, Duke University, Durham, NC 27708, USA
| | - Amanda E Hargrove
- Department of Chemistry, Duke University, Durham, NC 27708, USA.,Department of Biochemistry, Duke University School of Medicine, Durham, NC 27710, USA
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26
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Unveiling the druggable RNA targets and small molecule therapeutics. Bioorg Med Chem 2019; 27:2149-2165. [PMID: 30981606 PMCID: PMC7126819 DOI: 10.1016/j.bmc.2019.03.057] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 03/25/2019] [Accepted: 03/29/2019] [Indexed: 12/15/2022]
Abstract
The increasing appreciation for the crucial roles of RNAs in infectious and non-infectious human diseases makes them attractive therapeutic targets. Coding and non-coding RNAs frequently fold into complex conformations which, if effectively targeted, offer opportunities to therapeutically modulate numerous cellular processes, including those linked to undruggable protein targets. Despite the considerable skepticism as to whether RNAs can be targeted with small molecule therapeutics, overwhelming evidence suggests the challenges we are currently facing are not outside the realm of possibility. In this review, we highlight the most recent advances in molecular techniques that have sparked a revolution in understanding the RNA structure-to-function relationship. We bring attention to the application of these modern techniques to identify druggable RNA targets and to assess small molecule binding specificity. Finally, we discuss novel screening methodologies that support RNA drug discovery and present examples of therapeutically valuable RNA targets.
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27
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Kesy J, Patil KM, Kumar SR, Shu Z, Yong HY, Zimmermann L, Ong AAL, Toh DFK, Krishna MS, Yang L, Decout JL, Luo D, Prabakaran M, Chen G, Kierzek E. A Short Chemically Modified dsRNA-Binding PNA (dbPNA) Inhibits Influenza Viral Replication by Targeting Viral RNA Panhandle Structure. Bioconjug Chem 2019; 30:931-943. [PMID: 30721034 DOI: 10.1021/acs.bioconjchem.9b00039] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
RNAs play critical roles in diverse catalytic and regulatory biological processes and are emerging as important disease biomarkers and therapeutic targets. Thus, developing chemical compounds for targeting any desired RNA structures has great potential in biomedical applications. The viral and cellular RNA sequence and structure databases lay the groundwork for developing RNA-binding chemical ligands through the recognition of both RNA sequence and RNA structure. Influenza A virion consists of eight segments of negative-strand viral RNA (vRNA), all of which contain a highly conserved panhandle duplex structure formed between the first 13 nucleotides at the 5' end and the last 12 nucleotides at the 3' end. Here, we report our binding and cell culture anti-influenza assays of a short 10-mer chemically modified double-stranded RNA (dsRNA)-binding peptide nucleic acid (PNA) designed to bind to the panhandle duplex structure through novel major-groove PNA·RNA2 triplex formation. We demonstrated that incorporation of chemically modified PNA residues thio-pseudoisocytosine (L) and guanidine-modified 5-methyl cytosine (Q) previously developed by us facilitates the sequence-specific recognition of Watson-Crick G-C and C-G pairs, respectively, at physiologically relevant conditions. Significantly, the chemically modified dsRNA-binding PNA (dbPNA) shows selective binding to the dsRNA region in panhandle structure over a single-stranded RNA (ssRNA) and a dsDNA containing the same sequence. The panhandle structure is not accessible to traditional antisense DNA or RNA with a similar length. Conjugation of the dbPNA with an aminosugar neamine enhances the cellular uptake. We observed that 2-5 μM dbPNA-neamine conjugate results in a significant reduction of viral replication. In addition, the 10-mer dbPNA inhibits innate immune receptor RIG-I binding to panhandle structure and thus RIG-I ATPase activity. These findings would provide the foundation for developing novel dbPNAs for the detection of influenza viral RNAs and therapeutics with optimal antiviral and immunomodulatory activities.
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Affiliation(s)
- Julita Kesy
- Institute of Bioorganic Chemistry, Polish Academy of Sciences , Noskowskiego 12/14 , 61-704 Poznan , Poland
| | - Kiran M Patil
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences , Nanyang Technological University , 21 Nanyang Link , 637371 , Singapore
| | | | - Zhiyu Shu
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences , Nanyang Technological University , 21 Nanyang Link , 637371 , Singapore
| | - Hui Yee Yong
- Lee Kong Chian School of Medicine , Nanyang Technological University , EMB 03-07, 59 Nanyang Drive , 636921 , Singapore.,NTU Institute of Structural Biology , Nanyang Technological University , EMB 06-01, 59 Nanyang Drive , 636921 , Singapore.,School of Biological Sciences , Nanyang Technological University , 60 Nanyang Drive , 636921 , Singapore
| | - Louis Zimmermann
- Département de Pharmacochimie Moléculaire , University Grenoble Alpes, CNRS, ICMG FR 2607, UMR 5063 , 470 Rue de la Chimie , F-38041 Grenoble , France
| | - Alan Ann Lerk Ong
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences , Nanyang Technological University , 21 Nanyang Link , 637371 , Singapore
| | - Desiree-Faye Kaixin Toh
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences , Nanyang Technological University , 21 Nanyang Link , 637371 , Singapore
| | - Manchugondanahalli S Krishna
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences , Nanyang Technological University , 21 Nanyang Link , 637371 , Singapore
| | - Lixia Yang
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences , Nanyang Technological University , 21 Nanyang Link , 637371 , Singapore
| | - Jean-Luc Decout
- Département de Pharmacochimie Moléculaire , University Grenoble Alpes, CNRS, ICMG FR 2607, UMR 5063 , 470 Rue de la Chimie , F-38041 Grenoble , France
| | - Dahai Luo
- Lee Kong Chian School of Medicine , Nanyang Technological University , EMB 03-07, 59 Nanyang Drive , 636921 , Singapore.,NTU Institute of Structural Biology , Nanyang Technological University , EMB 06-01, 59 Nanyang Drive , 636921 , Singapore
| | - Mookkan Prabakaran
- Temasek Life Science Laboratory, 1 Research Link , National University of Singapore , 117604 , Singapore
| | - Gang Chen
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences , Nanyang Technological University , 21 Nanyang Link , 637371 , Singapore
| | - Elzbieta Kierzek
- Institute of Bioorganic Chemistry, Polish Academy of Sciences , Noskowskiego 12/14 , 61-704 Poznan , Poland
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28
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Sato Y, Yajima S, Taguchi A, Baba K, Nakagomi M, Aiba Y, Nishizawa S. Trimethine cyanine dyes as deep-red fluorescent indicators with high selectivity to the internal loop of the bacterial A-site RNA. Chem Commun (Camb) 2019; 55:3183-3186. [DOI: 10.1039/c9cc00414a] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
We report that TO-PRO-3 functions as a deep-red fluorescent indicator for the internal loop structure of the bacterial (Escherichia coli) A-site, which enables the assessment of A-site binding capability of various test compounds including blue and even-green-emitting compounds.
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Affiliation(s)
- Yusuke Sato
- Department of Chemistry
- Graduate School of Science
- Tohoku University
- Sendai 980-8578
- Japan
| | - Sayaka Yajima
- Department of Chemistry
- Graduate School of Science
- Tohoku University
- Sendai 980-8578
- Japan
| | - Akifumi Taguchi
- Department of Chemistry
- Graduate School of Science
- Tohoku University
- Sendai 980-8578
- Japan
| | - Kyosuke Baba
- Department of Chemistry
- Graduate School of Science
- Tohoku University
- Sendai 980-8578
- Japan
| | - Mayu Nakagomi
- Department of Chemistry
- Graduate School of Science
- Tohoku University
- Sendai 980-8578
- Japan
| | - Yuri Aiba
- Department of Chemistry
- Graduate School of Science
- Tohoku University
- Sendai 980-8578
- Japan
| | - Seiichi Nishizawa
- Department of Chemistry
- Graduate School of Science
- Tohoku University
- Sendai 980-8578
- Japan
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29
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Chavez-Calvillo G, Martin S, Hamm C, Sztuba-Solinska J. The Structure-To-Function Relationships of Gammaherpesvirus-Encoded Long Non-Coding RNAs and Their Contributions to Viral Pathogenesis. Noncoding RNA 2018; 4:ncrna4040024. [PMID: 30261651 PMCID: PMC6315926 DOI: 10.3390/ncrna4040024] [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: 08/31/2018] [Revised: 09/17/2018] [Accepted: 09/18/2018] [Indexed: 12/17/2022] Open
Abstract
Advances in next-generation sequencing have facilitated the discovery of a multitude of long non-coding RNAs (lncRNAs) with pleiotropic functions in cellular processes, disease, and viral pathogenesis. It came as no surprise when viruses were also revealed to transcribe their own lncRNAs. Among them, gammaherpesviruses, one of the three subfamilies of the Herpesviridae, code their largest number. These structurally and functionally intricate non-coding (nc) transcripts modulate cellular and viral gene expression to maintain viral latency or prompt lytic reactivation. These lncRNAs allow for the virus to escape cytosolic surveillance, sequester, and re-localize essential cellular factors and modulate the cell cycle and proliferation. Some viral lncRNAs act as “messenger molecules”, transferring information about viral infection to neighboring cells. This broad range of lncRNA functions is achieved through lncRNA structure-mediated interactions with effector molecules of viral and host origin, including other RNAs, proteins and DNAs. In this review, we discuss examples of gammaherpesvirus-encoded lncRNAs, emphasize their unique structural attributes, and link them to viral life cycle, pathogenesis, and disease progression. We will address their potential as novel targets for drug discovery and propose future directions to explore lncRNA structure and function relationship.
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Affiliation(s)
- Gabriela Chavez-Calvillo
- Department of Biological Sciences, Auburn University, 120 W. Samford Ave, Rouse Life Sciences Building, Auburn, AL 36849, USA.
| | - Sarah Martin
- Department of Biological Sciences, Auburn University, 120 W. Samford Ave, Rouse Life Sciences Building, Auburn, AL 36849, USA.
| | - Chad Hamm
- Department of Biological Sciences, Auburn University, 120 W. Samford Ave, Rouse Life Sciences Building, Auburn, AL 36849, USA.
| | - Joanna Sztuba-Solinska
- Department of Biological Sciences, Auburn University, 120 W. Samford Ave, Rouse Life Sciences Building, Auburn, AL 36849, USA.
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30
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Warner KD, Hajdin CE, Weeks KM. Principles for targeting RNA with drug-like small molecules. Nat Rev Drug Discov 2018; 17:547-558. [PMID: 29977051 PMCID: PMC6420209 DOI: 10.1038/nrd.2018.93] [Citation(s) in RCA: 410] [Impact Index Per Article: 68.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Recent studies have indicated the potential to develop small-molecule drugs that act on RNA targets, leading to burgeoning interest in the field. This article discusses general principles for discovering small-molecule drugs that target RNA and argues that the overarching challenge is to identify appropriate target structures in disease-causing RNAs that have high information content and, consequently, appropriate ligand-binding pockets. RNA molecules are essential for cellular information transfer and gene regulation, and RNAs have been implicated in many human diseases. Messenger and non-coding RNAs contain highly structured elements, and evidence suggests that many of these structures are important for function. Targeting these RNAs with small molecules offers opportunities to therapeutically modulate numerous cellular processes, including those linked to 'undruggable' protein targets. Despite this promise, there is currently only a single class of human-designed small molecules that target RNA used clinically — the linezolid antibiotics. However, a growing number of small-molecule RNA ligands are being identified, leading to burgeoning interest in the field. Here, we discuss principles for discovering small-molecule drugs that target RNA and argue that the overarching challenge is to identify appropriate target structures — namely, in disease-causing RNAs that have high information content and, consequently, appropriate ligand-binding pockets. If focus is placed on such druggable binding sites in RNA, extensive knowledge of the typical physicochemical properties of drug-like small molecules could then enable small-molecule drug discovery for RNA targets to become (only) roughly as difficult as for protein targets.
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Affiliation(s)
| | | | - Kevin M Weeks
- Department of Chemistry, University of North Carolina, Chapel Hill, NC, USA
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31
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Velagapudi SP, Costales MG, Vummidi BR, Nakai Y, Angelbello AJ, Tran T, Haniff HS, Matsumoto Y, Wang ZF, Chatterjee AK, Childs-Disney JL, Disney MD. Approved Anti-cancer Drugs Target Oncogenic Non-coding RNAs. Cell Chem Biol 2018; 25:1086-1094.e7. [PMID: 30251629 DOI: 10.1016/j.chembiol.2018.05.015] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 04/03/2018] [Accepted: 05/18/2018] [Indexed: 12/14/2022]
Abstract
Potential RNA drug targets for small molecules are found throughout the human transcriptome, yet small molecules known to elicit a pharmacological response by directly targeting RNA are limited to antibacterials. Herein, we describe AbsorbArray, a small molecule microarray-based approach that allows for unmodified compounds, including FDA-approved drugs, to be probed for binding to RNA motif libraries in a massively parallel format. Several drug classes bind RNA including kinase and topoisomerase inhibitors. The latter avidly bound the motif found in the Dicer site of oncogenic microRNA (miR)-21 and inhibited its processing both in vitro and in cells. The most potent compound de-repressed a downstream protein target and inhibited a miR-21-mediated invasive phenotype. The compound's activity was ablated upon overexpression of pre-miR-21. Target validation via chemical crosslinking and isolation by pull-down showed direct engagement of pre-miR-21 by the small molecule in cells, demonstrating that RNAs should indeed be considered druggable.
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Affiliation(s)
- Sai Pradeep Velagapudi
- Department of Chemistry, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA
| | - Matthew G Costales
- Department of Chemistry, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA
| | - Balayeshwanth R Vummidi
- Department of Chemistry, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA
| | - Yoshio Nakai
- Department of Chemistry, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA
| | - Alicia J Angelbello
- Department of Chemistry, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA
| | - Tuan Tran
- Department of Chemistry, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA
| | - Hafeez S Haniff
- Department of Chemistry, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA
| | - Yasumasa Matsumoto
- Department of Chemistry, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA
| | - Zi Fu Wang
- Department of Chemistry, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA
| | - Arnab K Chatterjee
- California Institute for Biomedical Research (CALIBR), 11119 North Torrey Pines Road, Suite 100, La Jolla, CA 92037, USA
| | - Jessica L Childs-Disney
- Department of Chemistry, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA
| | - Matthew D Disney
- Department of Chemistry, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA.
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32
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Ferhadian D, Contrant M, Printz-Schweigert A, Smyth RP, Paillart JC, Marquet R. Structural and Functional Motifs in Influenza Virus RNAs. Front Microbiol 2018; 9:559. [PMID: 29651275 PMCID: PMC5884886 DOI: 10.3389/fmicb.2018.00559] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 03/12/2018] [Indexed: 12/22/2022] Open
Abstract
Influenza A viruses (IAV) are responsible for recurrent influenza epidemics and occasional devastating pandemics in humans and animals. They belong to the Orthomyxoviridae family and their genome consists of eight (-) sense viral RNA (vRNA) segments of different lengths coding for at least 11 viral proteins. A heterotrimeric polymerase complex is bound to the promoter consisting of the 13 5′-terminal and 12 3′-terminal nucleotides of each vRNA, while internal parts of the vRNAs are associated with multiple copies of the viral nucleoprotein (NP), thus forming ribonucleoproteins (vRNP). Transcription and replication of vRNAs result in viral mRNAs (vmRNAs) and complementary RNAs (cRNAs), respectively. Complementary RNAs are the exact positive copies of vRNAs; they also form ribonucleoproteins (cRNPs) and are intermediate templates in the vRNA amplification process. On the contrary, vmRNAs have a 5′ cap snatched from cellular mRNAs and a 3′ polyA tail, both gained by the viral polymerase complex. Hence, unlike vRNAs and cRNAs, vmRNAs do not have a terminal promoter able to recruit the viral polymerase. Furthermore, synthesis of at least two viral proteins requires vmRNA splicing. Except for extensive analysis of the viral promoter structure and function and a few, mostly bioinformatics, studies addressing the vRNA and vmRNA structure, structural studies of the influenza A vRNAs, cRNAs, and vmRNAs are still in their infancy. The recent crystal structures of the influenza polymerase heterotrimeric complex drastically improved our understanding of the replication and transcription processes. The vRNA structure has been mainly studied in vitro using RNA probing, but its structure has been very recently studied within native vRNPs using crosslinking and RNA probing coupled to next generation RNA sequencing. Concerning vmRNAs, most studies focused on the segment M and NS splice sites and several structures initially predicted by bioinformatics analysis have now been validated experimentally and their role in the viral life cycle demonstrated. This review aims to compile the structural motifs found in the different RNA classes (vRNA, cRNA, and vmRNA) of influenza viruses and their function in the viral replication cycle.
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Affiliation(s)
- Damien Ferhadian
- CNRS - UPR 9002, Architecture et Réactivité de l'ARN, IBMC, Université de Strasbourg, Strasbourg, France
| | - Maud Contrant
- CNRS - UPR 9002, Architecture et Réactivité de l'ARN, IBMC, Université de Strasbourg, Strasbourg, France
| | - Anne Printz-Schweigert
- CNRS - UPR 9002, Architecture et Réactivité de l'ARN, IBMC, Université de Strasbourg, Strasbourg, France
| | - Redmond P Smyth
- CNRS - UPR 9002, Architecture et Réactivité de l'ARN, IBMC, Université de Strasbourg, Strasbourg, France
| | - Jean-Christophe Paillart
- CNRS - UPR 9002, Architecture et Réactivité de l'ARN, IBMC, Université de Strasbourg, Strasbourg, France
| | - Roland Marquet
- CNRS - UPR 9002, Architecture et Réactivité de l'ARN, IBMC, Université de Strasbourg, Strasbourg, France
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33
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Gómez Ramos LM, Degtyareva NN, Kovacs NA, Holguin SY, Jiang L, Petrov AS, Biesiada M, Hu MY, Purzycka KJ, Arya DP, Williams LD. Eukaryotic Ribosomal Expansion Segments as Antimicrobial Targets. Biochemistry 2017; 56:5288-5299. [PMID: 28895721 DOI: 10.1021/acs.biochem.7b00703] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Diversity in eukaryotic rRNA structure and function offers possibilities of therapeutic targets. Unlike ribosomes of prokaryotes, eukaryotic ribosomes contain species-specific rRNA expansion segments (ESs) with idiosyncratic structures and functions that are essential and specific to some organisms. Here we investigate expansion segment 7 (ES7), one of the largest and most variable expansions of the eukaryotic ribosome. We hypothesize that ES7 of the pathogenic fungi Candida albicans (ES7CA) could be a prototypic drug target. We show that isolated ES7CA folds reversibly to a native-like state. We developed a fluorescence displacement assay using an RNA binding fluorescent probe, F-neo. F-neo binds tightly to ES7CA with a Kd of 2.5 × 10-9 M but binds weakly to ES7 of humans (ES7HS) with a Kd estimated to be greater than 7 μM. The fluorescence displacement assay was used to investigate the affinities of a library of peptidic aminosugar conjugates (PAs) for ES7CA. For conjugates with highest affinities for ES7CA (NeoRH, NeoFH, and NeoYH), the lowest dose needed to induce mortality in C. albicans (minimum inhibitory concentration, MIC) was determined. PAs with the lowest MIC values were tested for cytotoxicity in HEK293T cells. Molecules with high affinity for ES7CA in vitro induce mortality in C. albicans but not in HEK293T cells. The results are consistent with the hypothesis that ESs represent useful targets for chemotherapeutics directed against eukaryotic pathogens.
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Affiliation(s)
- Lizzette M Gómez Ramos
- School of Chemistry and Biochemistry, Georgia Institute of Technology , 315 Ferst Drive NW, Atlanta, Georgia 30332-0363, United States.,School of Chemical and Biomolecular Engineering, Georgia Institute of Technology , 311 Ferst Drive NW, Atlanta, Georgia 30332-0100, United States
| | - Natalya N Degtyareva
- NUBAD, LLC , 900 B West Farris Road, Greenville, South Carolina 29605, United States
| | - Nicholas A Kovacs
- School of Chemistry and Biochemistry, Georgia Institute of Technology , 315 Ferst Drive NW, Atlanta, Georgia 30332-0363, United States
| | - Stefany Y Holguin
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology , 311 Ferst Drive NW, Atlanta, Georgia 30332-0100, United States
| | - Liuwei Jiang
- Department of Chemistry, Clemson University , 436 Hunter Laboratories, Clemson, South Carolina 29634-0973, United States
| | - Anton S Petrov
- School of Chemistry and Biochemistry, Georgia Institute of Technology , 315 Ferst Drive NW, Atlanta, Georgia 30332-0363, United States
| | - Marcin Biesiada
- RNA Structure and Function Laboratory, Institute of Bioorganic Chemistry, Polish Academy of Sciences , Poznan 61-704, Poland
| | - Michael Y Hu
- School of Chemistry and Biochemistry, Georgia Institute of Technology , 315 Ferst Drive NW, Atlanta, Georgia 30332-0363, United States
| | - Katarzyna J Purzycka
- RNA Structure and Function Laboratory, Institute of Bioorganic Chemistry, Polish Academy of Sciences , Poznan 61-704, Poland
| | - Dev P Arya
- NUBAD, LLC , 900 B West Farris Road, Greenville, South Carolina 29605, United States.,Department of Chemistry, Clemson University , 436 Hunter Laboratories, Clemson, South Carolina 29634-0973, United States
| | - Loren Dean Williams
- School of Chemistry and Biochemistry, Georgia Institute of Technology , 315 Ferst Drive NW, Atlanta, Georgia 30332-0363, United States
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34
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Chang AT, Tran M, Nikonowicz EP. Structure and Dynamics of the Tetra-A Loop and (A-A)-U Sequence Motif within the Coliphage GA Replicase RNA Operator. Biochemistry 2017; 56:2690-2700. [PMID: 28488852 DOI: 10.1021/acs.biochem.7b00123] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The three-dimensional structure of a RNA hairpin containing the RNA operator binding site for bacteriophage GA coat protein is presented. The phage GA operator contains the asymmetric (A-A)-U sequence motif and is capped by a four-adenine (tetra-A) loop. The uridine of the (A-A)-U motif preferentially pairs with the 5'-proximal cross-strand adenine, and the 3'-proximal adenine stacks into the helix. The tetra-A loop is well-ordered with adenine residues 2-4 forming a 3' stack. This loop conformation stands in contrast to the structure of the 5'-AUUA loop of the related phage MS2 operator in which residues 1 and 2 form a 5' stack. The context dependence of the (A-A)-U sequence motif conformation was examined using structures of 76 unique occurrences from the Protein Data Bank. The motif almost always has one adenine bulged and the other adenine adopting an A-U base pair. In the case in which the (A-A)-U motif is flanked by only one Watson-Crick base pair, the adenine adjacent to the flanking base pair tends to bulge; 80% of motifs with a 3' flanking pair have a 3' bulged adenine, and 84% of motifs with a 5' flanking pair have a 5' bulged adenine. The frequencies of 3'- and 5'-proximal adenines bulging are 33 and 67%, respectively, when the (A-A)-U motif is flanked by base pairs on both sides. Although a 3' flanking cytidine correlates (88%) with bulging of the 5'-proximal adenine, no strict dependence on flanking nucleotide identity was identified for the 5' side.
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Affiliation(s)
- Andrew T Chang
- Department of BioSciences, Rice University , Houston, Texas 77251-1892, United States
| | - Michelle Tran
- Department of BioSciences, Rice University , Houston, Texas 77251-1892, United States
| | - Edward P Nikonowicz
- Department of BioSciences, Rice University , Houston, Texas 77251-1892, United States
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35
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Affiliation(s)
- Amanda L. Garner
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan USA
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36
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Structure-Based Discovery of Small Molecules Binding to RNA. TOPICS IN MEDICINAL CHEMISTRY 2017. [DOI: 10.1007/7355_2016_29] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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37
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Connelly CM, Moon MH, Schneekloth JS. The Emerging Role of RNA as a Therapeutic Target for Small Molecules. Cell Chem Biol 2016; 23:1077-1090. [PMID: 27593111 PMCID: PMC5064864 DOI: 10.1016/j.chembiol.2016.05.021] [Citation(s) in RCA: 211] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 05/07/2016] [Accepted: 05/18/2016] [Indexed: 01/09/2023]
Abstract
Recent advances in understanding different RNAs and unique features of their biology have revealed a wealth of information. However, approaches to identify small molecules that target these newly discovered regulatory elements have been lacking. The application of new biochemical screening and design-based technologies, coupled with a resurgence of interest in phenotypic screening, has resulted in several compelling successes in targeting RNA. A number of recent advances suggest that achieving the long-standing goal of developing drug-like, biologically active small molecules that target RNA is possible. This review highlights advances and successes in approaches to targeting RNA with diverse small molecules, and the potential for these technologies to pave the way to new types of RNA-targeted therapeutics.
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Affiliation(s)
- Colleen M Connelly
- Chemical Biology Laboratory, National Cancer Institute, Frederick, MD 21702, USA
| | - Michelle H Moon
- Chemical Biology Laboratory, National Cancer Institute, Frederick, MD 21702, USA
| | - John S Schneekloth
- Chemical Biology Laboratory, National Cancer Institute, Frederick, MD 21702, USA.
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38
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Stevaert A, Naesens L. The Influenza Virus Polymerase Complex: An Update on Its Structure, Functions, and Significance for Antiviral Drug Design. Med Res Rev 2016; 36:1127-1173. [PMID: 27569399 PMCID: PMC5108440 DOI: 10.1002/med.21401] [Citation(s) in RCA: 119] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 05/18/2016] [Accepted: 06/24/2016] [Indexed: 12/11/2022]
Abstract
Influenza viruses cause seasonal epidemics and pandemic outbreaks associated with significant morbidity and mortality, and a huge cost. Since resistance to the existing anti‐influenza drugs is rising, innovative inhibitors with a different mode of action are urgently needed. The influenza polymerase complex is widely recognized as a key drug target, given its critical role in virus replication and high degree of conservation among influenza A (of human or zoonotic origin) and B viruses. We here review the major progress that has been made in recent years in unravelling the structure and functions of this protein complex, enabling structure‐aided drug design toward the core regions of the PA endonuclease, PB1 polymerase, or cap‐binding PB2 subunit. Alternatively, inhibitors may target a protein–protein interaction site, a cellular factor involved in viral RNA synthesis, the viral RNA itself, or the nucleoprotein component of the viral ribonucleoprotein. The latest advances made for these diverse pharmacological targets have yielded agents in advanced (i.e., favipiravir and VX‐787) or early clinical testing, besides several experimental inhibitors in various stages of development, which are all covered here.
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Affiliation(s)
| | - Lieve Naesens
- Rega Institute for Medical Research, KU Leuven, Leuven, Belgium.
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39
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Hermann T. Small molecules targeting viral RNA. WILEY INTERDISCIPLINARY REVIEWS-RNA 2016; 7:726-743. [PMID: 27307213 PMCID: PMC7169885 DOI: 10.1002/wrna.1373] [Citation(s) in RCA: 105] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 04/29/2016] [Accepted: 05/23/2016] [Indexed: 02/06/2023]
Abstract
Highly conserved noncoding RNA (ncRNA) elements in viral genomes and transcripts offer new opportunities to expand the repertoire of drug targets for the development of antiinfective therapy. Ligands binding to ncRNA architectures are able to affect interactions, structural stability or conformational changes and thereby block processes essential for viral replication. Proof of concept for targeting functional RNA by small molecule inhibitors has been demonstrated for multiple viruses with RNA genomes. Strategies to identify antiviral compounds as inhibitors of ncRNA are increasingly emphasizing consideration of drug‐like properties of candidate molecules emerging from screening and ligand design. Recent efforts of antiviral lead discovery for RNA targets have provided drug‐like small molecules that inhibit viral replication and include inhibitors of human immunodeficiency virus (HIV), hepatitis C virus (HCV), severe respiratory syndrome coronavirus (SARS CoV), and influenza A virus. While target selectivity remains a challenge for the discovery of useful RNA‐binding compounds, a better understanding is emerging of properties that define RNA targets amenable for inhibition by small molecule ligands. Insight from successful approaches of targeting viral ncRNA in HIV, HCV, SARS CoV, and influenza A will provide a basis for the future exploration of RNA targets for therapeutic intervention in other viral pathogens which create urgent, unmet medical needs. Viruses for which targeting ncRNA components in the genome or transcripts may be promising include insect‐borne flaviviruses (Dengue, Zika, and West Nile) and filoviruses (Ebola and Marburg). WIREs RNA 2016, 7:726–743. doi: 10.1002/wrna.1373 This article is categorized under:
RNA Structure and Dynamics > Influence of RNA Structure in Biological Systems RNA Interactions with Proteins and Other Molecules > Small Molecule–RNA Interactions Regulatory RNAs/RNAi/Riboswitches > Regulatory RNAs
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Affiliation(s)
- Thomas Hermann
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA. .,Center for Drug Discovery Innovation, University of California, San Diego, La Jolla, CA, USA.
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40
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Wang M, Yu Y, Liang C, Lu A, Zhang G. Recent Advances in Developing Small Molecules Targeting Nucleic Acid. Int J Mol Sci 2016; 17:ijms17060779. [PMID: 27248995 PMCID: PMC4926330 DOI: 10.3390/ijms17060779] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 05/01/2016] [Accepted: 05/09/2016] [Indexed: 12/19/2022] Open
Abstract
Nucleic acids participate in a large number of biological processes. However, current approaches for small molecules targeting protein are incompatible with nucleic acids. On the other hand, the lack of crystallization of nucleic acid is the limiting factor for nucleic acid drug design. Because of the improvements in crystallization in recent years, a great many structures of nucleic acids have been reported, providing basic information for nucleic acid drug discovery. This review focuses on the discovery and development of small molecules targeting nucleic acids.
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Affiliation(s)
- Maolin Wang
- Institute of Integrated Bioinfomedicine and Translational Science (IBTS), School of Chinese Medicine, Hong Kong Baptist University, Hong Kong 999077, China.
- Shenzhen Lab of Combinatorial Compounds and Targeted Drug Delivery, HKBU Institute of Research and Continuing Education, Shenzhen 518000, China.
- Institute for Advancing Translational Medicine in Bone and Joint Diseases, School of Chinese Medicine, Hong Kong Baptist University, Hong Kong 999077, China.
| | - Yuanyuan Yu
- Institute of Integrated Bioinfomedicine and Translational Science (IBTS), School of Chinese Medicine, Hong Kong Baptist University, Hong Kong 999077, China.
- Shenzhen Lab of Combinatorial Compounds and Targeted Drug Delivery, HKBU Institute of Research and Continuing Education, Shenzhen 518000, China.
- Institute for Advancing Translational Medicine in Bone and Joint Diseases, School of Chinese Medicine, Hong Kong Baptist University, Hong Kong 999077, China.
| | - Chao Liang
- Institute of Integrated Bioinfomedicine and Translational Science (IBTS), School of Chinese Medicine, Hong Kong Baptist University, Hong Kong 999077, China.
- Shenzhen Lab of Combinatorial Compounds and Targeted Drug Delivery, HKBU Institute of Research and Continuing Education, Shenzhen 518000, China.
- Institute for Advancing Translational Medicine in Bone and Joint Diseases, School of Chinese Medicine, Hong Kong Baptist University, Hong Kong 999077, China.
| | - Aiping Lu
- Institute of Integrated Bioinfomedicine and Translational Science (IBTS), School of Chinese Medicine, Hong Kong Baptist University, Hong Kong 999077, China.
- Shenzhen Lab of Combinatorial Compounds and Targeted Drug Delivery, HKBU Institute of Research and Continuing Education, Shenzhen 518000, China.
- Institute for Advancing Translational Medicine in Bone and Joint Diseases, School of Chinese Medicine, Hong Kong Baptist University, Hong Kong 999077, China.
| | - Ge Zhang
- Institute of Integrated Bioinfomedicine and Translational Science (IBTS), School of Chinese Medicine, Hong Kong Baptist University, Hong Kong 999077, China.
- Shenzhen Lab of Combinatorial Compounds and Targeted Drug Delivery, HKBU Institute of Research and Continuing Education, Shenzhen 518000, China.
- Institute for Advancing Translational Medicine in Bone and Joint Diseases, School of Chinese Medicine, Hong Kong Baptist University, Hong Kong 999077, China.
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41
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Frank AT. Can Holo NMR Chemical Shifts be Directly Used to Resolve RNA–Ligand Poses? J Chem Inf Model 2016; 56:368-76. [DOI: 10.1021/acs.jcim.5b00593] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Aaron T. Frank
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
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42
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Doyle SK, Pop MS, Evans HL, Koehler AN. Advances in discovering small molecules to probe protein function in a systems context. Curr Opin Chem Biol 2015; 30:28-36. [PMID: 26615565 DOI: 10.1016/j.cbpa.2015.10.032] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Revised: 10/30/2015] [Accepted: 10/30/2015] [Indexed: 12/15/2022]
Abstract
High throughput screening (HTS) has historically been used for drug discovery almost exclusively by the pharmaceutical industry. Due to a significant decrease in costs associated with establishing a high throughput facility and an exponential interest in discovering probes of development and disease associated biomolecules, HTS core facilities have become an integral part of most academic and non-profit research institutions over the past decade. This major shift has led to the development of new HTS methodologies extending beyond the capabilities and target classes used in classical drug discovery approaches such as traditional enzymatic activity-based screens. In this brief review we describe some of the most interesting developments in HTS technologies and methods for chemical probe discovery.
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Affiliation(s)
- Shelby K Doyle
- David H. Koch Institute for Integrative Cancer Research, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Marius S Pop
- David H. Koch Institute for Integrative Cancer Research, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Helen L Evans
- David H. Koch Institute for Integrative Cancer Research, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Angela N Koehler
- David H. Koch Institute for Integrative Cancer Research, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA; Broad Institute of MIT and Harvard, Cambridge, MA, USA.
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Abstract
![]()
Influenza A is an RNA virus with
a genome of eight negative sense
segments. Segment 7 mRNA contains a 3′ splice site for alternative
splicing to encode the essential M2 protein. On the basis of sequence
alignment and chemical mapping experiments, the secondary structure
surrounding the 3′ splice site has an internal loop, adenine
bulge, and hairpin loop when it is in the hairpin conformation that
exposes the 3′ splice site. We report structural features of
a three-dimensional model of the hairpin derived from nuclear magnetic
resonance spectra and simulated annealing with restrained molecular
dynamics. Additional insight was provided by modeling based on 1H chemical shifts. The internal loop containing the 3′
splice site has a dynamic guanosine and a stable imino (cis Watson–Crick/Watson–Crick) GA pair. The adenine bulge
also appears to be dynamic with the A either stacked in the stem or
forming a base triple with a Watson–Crick GC pair. The hairpin
loop is a GAAA tetraloop closed by an AC pair.
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Affiliation(s)
- Jonathan L Chen
- †Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
| | - Scott D Kennedy
- ‡Department of Biochemistry and Biophysics, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642, United States
| | - Douglas H Turner
- †Department of Chemistry, University of Rochester, Rochester, New York 14627, United States.,§Center for RNA Biology, University of Rochester, Rochester, New York 14627, United States
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Bottini A, De SK, Wu B, Tang C, Varani G, Pellecchia M. Targeting Influenza A Virus RNA Promoter. Chem Biol Drug Des 2015; 86:663-73. [PMID: 25676805 DOI: 10.1111/cbdd.12534] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Revised: 01/08/2015] [Accepted: 01/23/2015] [Indexed: 12/24/2022]
Abstract
The emergence of drug-resistant strains of influenza virus makes exploring new classes of inhibitors that target universally conserved viral targets a highly important goal. The influenza A viral genome is made up of eight single-stranded RNA-negative segments. The RNA promoter, consisting of the conserved sequences at the 3' and 5' end of each RNA genomic segment, is universally conserved among influenza A virus strains and in all segments. Previously, we reported on the identification and NMR structure of DPQ (6,7-dimethoxy-2-(1-piperazinyl)-4-quinazolinamine) (compound 1) in complex with the RNA promoter. Here, we report on additional screening and SAR studies with compound 1, including ex vivo anti-influenza activity assays, resulted in improved cellular activity against influenza A virus in the micromolar range.
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Affiliation(s)
- Angel Bottini
- Infectious and Inflammatory Disease Center and Cancer Center, Sanford Burnham Medical Research Institute, 10901 North Torrey Pines Road, La Jolla, CA, 92037, USA.,Sanford Burnham Graduate School of Biomedical Sciences, 10901 North Torrey Pines Road, La Jolla, CA, 92037, USA
| | - Surya K De
- Infectious and Inflammatory Disease Center and Cancer Center, Sanford Burnham Medical Research Institute, 10901 North Torrey Pines Road, La Jolla, CA, 92037, USA
| | - Bainan Wu
- Infectious and Inflammatory Disease Center and Cancer Center, Sanford Burnham Medical Research Institute, 10901 North Torrey Pines Road, La Jolla, CA, 92037, USA
| | - Changyan Tang
- Department of Chemistry, University of Washington, Seattle, WA, 98195-1700, USA
| | - Gabriele Varani
- Department of Chemistry, University of Washington, Seattle, WA, 98195-1700, USA
| | - Maurizio Pellecchia
- Infectious and Inflammatory Disease Center and Cancer Center, Sanford Burnham Medical Research Institute, 10901 North Torrey Pines Road, La Jolla, CA, 92037, USA
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Shortridge MD, Varani G. Structure based approaches for targeting non-coding RNAs with small molecules. Curr Opin Struct Biol 2015; 30:79-88. [PMID: 25687935 PMCID: PMC4416997 DOI: 10.1016/j.sbi.2015.01.008] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Revised: 01/19/2015] [Accepted: 01/28/2015] [Indexed: 12/22/2022]
Abstract
The increasing appreciation of the central role of non-coding RNAs (miRNAs and long non-coding RNAs) in chronic and degenerative human disease makes them attractive therapeutic targets. This would not be unprecedented: the bacterial ribosomal RNA is a mainstay for antibacterial treatment, while the conservation and functional importance of viral RNA regulatory elements has long suggested they would constitute attractive targets for new antivirals. Oligonucleotide-based chemistry has obvious appeals but also considerable pharmacological limitations that are yet to be addressed satisfactorily. Recent studies identifying small molecules targeting non-coding RNAs may provide an alternative approach to oligonucleotide methods. Here we review recent work investigating new structural and chemical principles for targeting RNA with small molecules.
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Affiliation(s)
- Matthew D Shortridge
- Department of Chemistry, University of Washington, Seattle, Box 351700, Seattle 98195, USA
| | - Gabriele Varani
- Department of Chemistry, University of Washington, Seattle, Box 351700, Seattle 98195, USA.
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Kapoor S, Dhama K. Prevention and Control of Influenza Viruses. INSIGHT INTO INFLUENZA VIRUSES OF ANIMALS AND HUMANS 2014. [PMCID: PMC7121144 DOI: 10.1007/978-3-319-05512-1_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The 2003–2004 outbreaks of highly pathogenic avian influenza (HPAI) have proven to be disastrous to the regional poultry industry in Asia, and have raised serious worldwide public health apprehension regarding the steps that should be taken to urgently control HPAI. Control measures must be taken based on the principles of biosecurity and disease management and at the same time making public aware of the precautionary measures at the verge of outbreak. Creation of protection and surveillance zones, various vaccination strategies viz. routine, preventive, emergency, mass and targeted vaccination programmes using live, inactivated and recombinant vaccines are the common strategies adopted in different parts of the globe. The new generation vaccines include recombinant vaccines and recombinant fusion vaccine. The pro-poor disease control programmes, giving compensation and subsidies to the farmers along with effective and efficient Veterinary Services forms integral part of control of HPAI. Following biosecurity principles and vaccination forms integral part of control programme against swine and equine influenza as well. Use of neuraminidase (NA) inhibitors (Zanamivir and Oseltamivir) for the treatment of human influenza has been widely accepted worldwide. The threat of increasing resistance of the flu viruses to these antivirals has evoked interest in the development of novel antiviral drugs for influenza virus such as inhibitors of cellular factors and host signalling cascades, cellular miRNAs, siRNA and innate immune peptides (defensins and cathelicidins). Commercial licensed inactivated vaccines for humans against influenza A and B viruses are available consisting of three influenza viruses: influenza type A subtype H3N2, influenza type A subtype H1N1 (seasonal) virus strain and influenza type B virus strain. As per WHO, use of tetravaccine consisting of antigens of influenza virus serotypes H3N2, H1N1, B and H5 is the most promising method to control influenza pandemic. All healthy children in many countries are required to be vaccinated between 6 and 59 months of age. The seasonal vaccines currently used in humans induce strain-specific humoral immunity as the antibodies. Universal influenza virus vaccines containing the relatively conserved ectodomain of M2 (M2e), M1, HA fusion peptide and stalk domains, NA, NP alone or in combination have been developed which have been shown to induce cross-protection. The T cell-based vaccines are another recent experimental approach that has been shown to elicit broad-spectrum heterosubtypic immunity in the host. As far as HPAI is concerned, various pandemic preparedness strategies have been documented.
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Affiliation(s)
- Sanjay Kapoor
- Department of Veterinary Microbiology, LLR University of Veterinary and Animal Sciences, Hisar, 125004 Haryana India
| | - Kuldeep Dhama
- Division of Pathology, Indian Veterinary Research Institute (IVRI), Izatnagar, Bareilly, 243122 Uttar Pradesh India
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