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Liu Y, Wang L, Zhao L, Zhang Y, Li ZT, Huang F. Multiple hydrogen bonding driven supramolecular architectures and their biomedical applications. Chem Soc Rev 2024; 53:1592-1623. [PMID: 38167687 DOI: 10.1039/d3cs00705g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Supramolecular chemistry combines the strength of molecular assembly via various molecular interactions. Hydrogen bonding facilitated self-assembly with the advantages of directionality, specificity, reversibility, and strength is a promising approach for constructing advanced supramolecules. There are still some challenges in hydrogen bonding based supramolecular polymers, such as complexity originating from tautomerism of the molecular building modules, the assembly process, and structure versatility of building blocks. In this review, examples are selected to give insights into multiple hydrogen bonding driven emerging supramolecular architectures. We focus on chiral supramolecular assemblies, multiple hydrogen bonding modules as stimuli responsive sources, interpenetrating polymer networks, multiple hydrogen bonding assisted organic frameworks, supramolecular adhesives, energy dissipators, and quantitative analysis of nano-adhesion. The applications in biomedical materials are focused with detailed examples including drug design evolution for myotonic dystrophy, molecular assembly for advanced drug delivery, an indicator displacement strategy for DNA detection, tissue engineering, and self-assembly complexes as gene delivery vectors for gene transfection. In addition, insights into the current challenges and future perspectives of this field to propel the development of multiple hydrogen bonding facilitated supramolecular materials are proposed.
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Affiliation(s)
- Yanxia Liu
- School of Materials and Energy, University of Electronic Science and Technology of China, Chengdu 611731, Sichuan, China.
| | - Lulu Wang
- State Key Laboratory of Chemistry and Utilization of Carbon-based Energy Resource, Xinjiang University, Urumqi, Xinjiang 830046, China
| | - Lin Zhao
- School of Materials and Energy, University of Electronic Science and Technology of China, Chengdu 611731, Sichuan, China.
| | - Yagang Zhang
- School of Materials and Energy, University of Electronic Science and Technology of China, Chengdu 611731, Sichuan, China.
| | - Zhan-Ting Li
- Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules, Shanghai Institute of Organic Chemistry (SIOC), Chinese Academy of Sciences, Shanghai 200032, China
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, 2205 Songhu Road, Shanghai 200438, China.
| | - Feihe Huang
- Stoddart Institute of Molecular Science, Department of Chemistry, Zhejiang University, Hangzhou 310058, China.
- ZJU-Hangzhou Global Scientific and Technological Innovation Center-Hangzhou Zhijiang Silicone Chemicals Co. Ltd. Joint Lab, Zhejiang-Israel Joint Laboratory of Self-Assembling Functional Materials, ZJU-Hangzhou Global Scientific and Technological Innovation Center, Zhejiang University, Hangzhou 311215, China
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2
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Kovachka S, Panosetti M, Grimaldi B, Azoulay S, Di Giorgio A, Duca M. Small molecule approaches to targeting RNA. Nat Rev Chem 2024; 8:120-135. [PMID: 38278932 DOI: 10.1038/s41570-023-00569-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/04/2023] [Indexed: 01/28/2024]
Abstract
The development of innovative methodologies to identify RNA binders has attracted enormous attention in chemical biology and drug discovery. Although antibiotics targeting bacterial ribosomal RNA have been on the market for decades, the renewed interest in RNA targeting reflects the need to better understand complex intracellular processes involving RNA. In this context, small molecules are privileged tools used to explore the biological functions of RNA and to validate RNAs as therapeutic targets, and they eventually are to become new drugs. Despite recent progress, the rational design of specific RNA binders requires a better understanding of the interactions which occur with the RNA target to reach the desired biological response. In this Review, we discuss the challenges to approaching this underexplored chemical space, together with recent strategies to bind, interact and affect biologically relevant RNAs.
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Affiliation(s)
- Sandra Kovachka
- Université Côte d'Azur, CNRS, Institute of Chemistry of Nice, Nice, France
| | - Marc Panosetti
- Université Côte d'Azur, CNRS, Institute of Chemistry of Nice, Nice, France
- Molecular Medicine Research Line, Istituto Italiano di Tecnologia (IIT), Genoa, Italy
| | - Benedetto Grimaldi
- Molecular Medicine Research Line, Istituto Italiano di Tecnologia (IIT), Genoa, Italy
| | - Stéphane Azoulay
- Université Côte d'Azur, CNRS, Institute of Chemistry of Nice, Nice, France
| | - Audrey Di Giorgio
- Université Côte d'Azur, CNRS, Institute of Chemistry of Nice, Nice, France
| | - Maria Duca
- Université Côte d'Azur, CNRS, Institute of Chemistry of Nice, Nice, France.
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3
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Deng S, Yi P, Xu M, Yi Q, Feng J. Dysfunctional gene splicing in glucose metabolism may contribute to Alzheimer's disease. Chin Med J (Engl) 2023; 136:666-675. [PMID: 35830275 PMCID: PMC10129079 DOI: 10.1097/cm9.0000000000002214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Indexed: 11/26/2022] Open
Abstract
ABSTRACT The glucose metabolism is crucial for sustained brain activity as it provides energy and is a carbon source for multiple biomacromolecules; glucose metabolism decreases dramatically in Alzheimer's disease (AD) and may be a fundamental cause for its development. Recent studies reveal that the alternative splicing events of certain genes effectively regulate several processes in glucose metabolism including insulin receptor, insulin-degrading enzyme, pyruvate kinase M, receptor for advanced glycation endproducts, and others, thereby, influencing glucose uptake, glycolysis, and advanced glycation end-products-mediated signaling pathways. Indeed, the discovery of aberrant alternative splicing that changes the proteomic diversity and protein activity in glucose metabolism has been pivotal in our understanding of AD development. In this review, we summarize the alternative splicing events of the glucose metabolism-related genes in AD pathology and highlight the crucial regulatory roles of splicing factors in the alternative splicing process. We also discuss the emerging therapeutic approaches for targeting splicing factors for AD treatment.
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Affiliation(s)
- Shengfeng Deng
- Laboratory of Anesthesiology, Department of Anesthesiology, the Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan 646000, China
| | - Peng Yi
- Laboratory of Anesthesiology, Department of Anesthesiology, the Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan 646000, China
| | - Mingliang Xu
- Laboratory of Anesthesiology, Department of Anesthesiology, the Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan 646000, China
| | - Qian Yi
- Department of Physiology, School of Basic Medical Sciences, Southwest Medical University, Luzhou, Sichuan 646000, China
| | - Jianguo Feng
- Laboratory of Anesthesiology, Department of Anesthesiology, the Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan 646000, China
- Affiliated Xinhui Hospital, Southern Medical University (People's Hospital of Xinhui District), Jiangmen, Guangdong 529100, China
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4
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Krueger SB, Lanzendorf AN, Jeon HH, Zimmerman SC. Selective and Reversible Ligand Assembly on the DNA and RNA Repeat Sequences in Myotonic Dystrophy. Chembiochem 2022; 23:e202200260. [PMID: 35790065 PMCID: PMC9733911 DOI: 10.1002/cbic.202200260] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 07/03/2022] [Indexed: 02/06/2023]
Abstract
Small molecule targeting of DNA and RNA sequences has come into focus as a therapeutic strategy for diseases such as myotonic dystrophy type 1 (DM1), a trinucleotide repeat disease characterized by RNA gain-of-function. Herein, we report a novel template-selected, reversible assembly of therapeutic agents in situ via aldehyde-amine condensation. Rationally designed small molecule targeting agents functionalized with either an aldehyde or an amine were synthesized and screened against the target nucleic acid sequence. The assembly of fragments was confirmed by MALDI-MS in the presence of DM1-relevant nucleic acid sequences. The resulting hit combinations of aldehyde and amine inhibited the formation of r(CUG)exp in vitro in a cooperative manner at low micromolar levels and rescued mis-splicing defects in DM1 model cells. This reversible template-selected assembly is a promising approach to achieve cell permeable and multivalent targeting via in situ synthesis and could be applied to other nucleic acid targets.
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Affiliation(s)
- Sarah B Krueger
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S Mathews Ave, Urbana, IL 61801, USA
| | - Amie N Lanzendorf
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S Mathews Ave, Urbana, IL 61801, USA
| | - Hyoeun Heather Jeon
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S Mathews Ave, Urbana, IL 61801, USA
| | - Steven C Zimmerman
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S Mathews Ave, Urbana, IL 61801, USA
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5
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Das B, Nagano K, Kawai G, Murata A, Nakatani K. 2-Amino-1,8-naphthyridine Dimer (ANP77), a High-Affinity Binder to the Internal Loops of C/CC and T/CC Sites in Double-Stranded DNA. J Org Chem 2021; 87:340-350. [PMID: 34937340 DOI: 10.1021/acs.joc.1c02383] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Small molecules targeting DNA regions with structural fluctuation are an important class of molecule as chemical probes for studying the role of these structures in biological systems and the development of neurological disorders. The molecule ANP77 we described here, where a three-atom linker connects two 2-amino-1,8-naphthyridines at the C7 position, was found to form stacked structure with protonation of naphthyridine at low pH, and bound to the internal loop consisting of C/CC and T/CC in double-stranded DNA with affinities of 4.8 and 34.4 nM, respectively. Mass spectrometry and isothermal titration calorimetry analyses determined the stoichiometry for the binding as 1:1, and chemical footprinting with permanganate and NMR structural analysis revealed that the T in the T/CC was forced to flip out toward an extrahelical position upon ANP77 binding. Protonated stacked ANP77 interacted with two adjacent cytosines through hydrogen bonding and occupied the position in the duplex by flipping out the C or T opposite CC. Finally, this study demonstrated the potential of ANP77 for binding to the sequences of biological significance with the TG(T/C)CC repeat of the PIG3 promoter and the telomere repeat CCCTAA.
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Affiliation(s)
- Bimolendu Das
- Department of Regulatory Bioorganic Chemistry, SANKEN (The Institute of Scientific and Industrial Research), Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan
| | - Konami Nagano
- Department of Life and Environmental Sciences, Faculty of Engineering, Chiba Institute of Technology, Chiba 275-0016, Japan
| | - Gota Kawai
- Department of Life and Environmental Sciences, Faculty of Engineering, Chiba Institute of Technology, Chiba 275-0016, Japan
| | - Asako Murata
- Department of Regulatory Bioorganic Chemistry, SANKEN (The Institute of Scientific and Industrial Research), Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan
| | - Kazuhiko Nakatani
- Department of Regulatory Bioorganic Chemistry, SANKEN (The Institute of Scientific and Industrial Research), Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan
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6
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Bush JA, Williams CC, Meyer SM, Tong Y, Haniff HS, Childs-Disney JL, Disney MD. Systematically Studying the Effect of Small Molecules Interacting with RNA in Cellular and Preclinical Models. ACS Chem Biol 2021; 16:1111-1127. [PMID: 34166593 PMCID: PMC8867596 DOI: 10.1021/acschembio.1c00014] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The interrogation and manipulation of biological systems by small molecules is a powerful approach in chemical biology. Ideal compounds selectively engage a target and mediate a downstream phenotypic response. Although historically small molecule drug discovery has focused on proteins and enzymes, targeting RNA is an attractive therapeutic alternative, as many disease-causing or -associated RNAs have been identified through genome-wide association studies. As the field of RNA chemical biology emerges, the systematic evaluation of target validation and modulation of target-associated pathways is of paramount importance. In this Review, through an examination of case studies, we outline the experimental characterization, including methods and tools, to evaluate comprehensively the impact of small molecules that target RNA on cellular phenotype.
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Affiliation(s)
- Jessica A Bush
- The Scripps Research Institute, Department of Chemistry, 130 Scripps Way, Jupiter, Florida 33458, United States
| | - Christopher C Williams
- The Scripps Research Institute, Department of Chemistry, 130 Scripps Way, Jupiter, Florida 33458, United States
| | - Samantha M Meyer
- The Scripps Research Institute, Department of Chemistry, 130 Scripps Way, Jupiter, Florida 33458, United States
| | - Yuquan Tong
- The Scripps Research Institute, Department of Chemistry, 130 Scripps Way, Jupiter, Florida 33458, United States
| | - Hafeez S Haniff
- The Scripps Research Institute, Department of Chemistry, 130 Scripps Way, Jupiter, Florida 33458, United States
| | - Jessica L Childs-Disney
- The Scripps Research Institute, Department of Chemistry, 130 Scripps Way, Jupiter, Florida 33458, United States
| | - Matthew D Disney
- The Scripps Research Institute, Department of Chemistry, 130 Scripps Way, Jupiter, Florida 33458, United States
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7
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Li K, Krueger SB, Zimmerman SC. A Novel Minor Groove Binder as a Potential Therapeutic Agent for Myotonic Dystrophy Type 1. ChemMedChem 2021; 16:2638-2644. [PMID: 34114350 DOI: 10.1002/cmdc.202100243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Indexed: 11/10/2022]
Abstract
Myotonic dystrophy type 1 (DM1) is a multisystemic neuromuscular disorder that is inherited in an autosomal dominant manner. DM1 originates in a (CTG⋅CAG) repeat expansion in the 3'-UTR of the dystrophia myotonic protein kinase (DMPK) gene on chromosome 19. One of the transcripts, r(CUG)exp , is toxic in various ways. Herein we report a rationally designed small molecule with a thiazole peptidomimetic unit that can serve as a minor groove binder for the nucleic acid targets. This peptide unit linked to two triaminotriazine recognition units selectively binds to d(CTG)exp to inhibit the transcription process, and also targets r(CUG)exp selectively to improve representative DM1 pathological molecular features, including foci formation and pre-mRNA splicing defects in DM1 model cells. As such, it represents a new structure type that might serve as a lead compound for future structure-activity optimization.
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Affiliation(s)
- Ke Li
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S Mathews Avenue, 61801, Urbana, IL, USA
| | - Sarah B Krueger
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S Mathews Avenue, 61801, Urbana, IL, USA
| | - Steven C Zimmerman
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S Mathews Avenue, 61801, Urbana, IL, USA
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8
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Ondono R, Lirio Á, Elvira C, Álvarez-Marimon E, Provenzano C, Cardinali B, Pérez-Alonso M, Perálvarez-Marín A, Borrell JI, Falcone G, Estrada-Tejedor R. Design of novel small molecule base-pair recognizers of toxic CUG RNA transcripts characteristics of DM1. Comput Struct Biotechnol J 2020; 19:51-61. [PMID: 33363709 PMCID: PMC7753043 DOI: 10.1016/j.csbj.2020.11.053] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Revised: 11/25/2020] [Accepted: 11/28/2020] [Indexed: 01/11/2023] Open
Abstract
Myotonic Dystrophy type 1 (DM1) is an incurable neuromuscular disorder caused by toxic DMPK transcripts that carry CUG repeat expansions in the 3' untranslated region (3'UTR). The intrinsic complexity and lack of crystallographic data makes noncoding RNA regions challenging targets to study in the field of drug discovery. In DM1, toxic transcripts tend to stall in the nuclei forming complex inclusion bodies called foci and sequester many essential alternative splicing factors such as Muscleblind-like 1 (MBNL1). Most DM1 phenotypic features stem from the reduced availability of free MBNL1 and therefore many therapeutic efforts are focused on recovering its normal activity. For that purpose, herein we present pyrido[2,3-d]pyrimidin-7-(8H)-ones, a privileged scaffold showing remarkable biological activity against many targets involved in human disorders including cancer and viral diseases. Their combination with a flexible linker meets the requirements to stabilise DM1 toxic transcripts, and therefore, enabling the release of MBNL1. Therefore, a set of novel pyrido[2,3-d]pyrimidin-7-(8H)-ones derivatives (1a-e) were obtained using click chemistry. 1a exerted over 20% MBNL1 recovery on DM1 toxic RNA activity in primary cell biology studies using patient-derived myoblasts. 1a promising anti DM1 activity may lead to subsequent generations of ligands, highlighting a new affordable treatment against DM1.
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Affiliation(s)
- Raul Ondono
- IQS School of Engineering, Universitat Ramon Llull, Barcelona, Spain
| | - Ángel Lirio
- IQS School of Engineering, Universitat Ramon Llull, Barcelona, Spain
| | - Carlos Elvira
- IQS School of Engineering, Universitat Ramon Llull, Barcelona, Spain
| | - Elena Álvarez-Marimon
- Biophysics Unit, Department of Biochemistry and Molecular Biology, School of Medicine, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
| | - Claudia Provenzano
- Institute of Biochemistry and Cell Biology, National Research Council, Monterotondo, Rome, Italy
| | - Beatrice Cardinali
- Institute of Biochemistry and Cell Biology, National Research Council, Monterotondo, Rome, Italy
| | - Manuel Pérez-Alonso
- Translational Genomics Group, Incliva Health Research Institute, Valencia, Spain
- Department of Genetics and Interdisciplinary Research Structure for Biotechnology and Biomedicine, University of Valencia, Valencia, Spain
| | - Alex Perálvarez-Marín
- Biophysics Unit, Department of Biochemistry and Molecular Biology, School of Medicine, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
| | - José I. Borrell
- IQS School of Engineering, Universitat Ramon Llull, Barcelona, Spain
| | - Germana Falcone
- Institute of Biochemistry and Cell Biology, National Research Council, Monterotondo, Rome, Italy
| | - Roger Estrada-Tejedor
- IQS School of Engineering, Universitat Ramon Llull, Barcelona, Spain
- Corresponding author.
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9
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Matsumoto J, Nakamori M, Okamoto T, Murata A, Dohno C, Nakatani K. The Dimeric Form of 1,3-Diaminoisoquinoline Derivative Rescued the Mis-splicing of Atp2a1 and Clcn1 Genes in Myotonic Dystrophy Type 1 Mouse Model. Chemistry 2020; 26:14305-14309. [PMID: 32449537 PMCID: PMC7702137 DOI: 10.1002/chem.202001572] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 05/21/2020] [Indexed: 12/25/2022]
Abstract
Expanded CUG repeat RNA in the dystrophia myotonia protein kinase (DMPK) gene causes myotonic dystrophy type 1 (DM1) and sequesters RNA processing proteins, such as the splicing factor muscleblind-like 1 protein (MBNL1). Sequestration of splicing factors results in the mis-splicing of some pre-mRNAs. Small molecules that rescue the mis-splicing in the DM1 cells have drawn attention as potential drugs to treat DM1. Herein we report a new molecule JM642 consisted of two 1,3-diaminoisoquinoline chromophores having an auxiliary aromatic unit at the C5 position. JM642 alternates the splicing pattern of the pre-mRNA of the Ldb3 gene in the DM1 cell model and Clcn1 and Atp2a1 genes in the DM1 mouse model. In vitro binding analysis by surface plasmon resonance (SPR) assay to the r(CUG) repeat and disruption of ribonuclear foci in the DM1 cell model suggested the binding of JM642 to the expanded r(CUG) repeat in vivo, eventually rescue the mis-splicing.
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Affiliation(s)
- Jun Matsumoto
- Department of Regulatory Bioorganic ChemistryThe Institute of Scientific and Industrial ResearchOsaka University8-1 MihogaokaIbaraki567-0047Japan
| | - Masayuki Nakamori
- Department of NeurologyGraduate School of MedicineOsaka University2-2 YamadaokaSuita565-0871Japan
| | - Tatsumasa Okamoto
- Department of Regulatory Bioorganic ChemistryThe Institute of Scientific and Industrial ResearchOsaka University8-1 MihogaokaIbaraki567-0047Japan
| | - Asako Murata
- Department of Regulatory Bioorganic ChemistryThe Institute of Scientific and Industrial ResearchOsaka University8-1 MihogaokaIbaraki567-0047Japan
| | - Chikara Dohno
- Department of Regulatory Bioorganic ChemistryThe Institute of Scientific and Industrial ResearchOsaka University8-1 MihogaokaIbaraki567-0047Japan
| | - Kazuhiko Nakatani
- Department of Regulatory Bioorganic ChemistryThe Institute of Scientific and Industrial ResearchOsaka University8-1 MihogaokaIbaraki567-0047Japan
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10
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Xu B, Meng Y, Jin Y. RNA structures in alternative splicing and back-splicing. WILEY INTERDISCIPLINARY REVIEWS-RNA 2020; 12:e1626. [PMID: 32929887 DOI: 10.1002/wrna.1626] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 08/14/2020] [Accepted: 08/22/2020] [Indexed: 12/12/2022]
Abstract
Alternative splicing greatly expands the transcriptomic and proteomic diversities related to physiological and developmental processes in higher eukaryotes. Splicing of long noncoding RNAs, and back- and trans- splicing further expanded the regulatory repertoire of alternative splicing. RNA structures were shown to play an important role in regulating alternative splicing and back-splicing. Application of novel sequencing technologies made it possible to identify genome-wide RNA structures and interaction networks, which might provide new insights into RNA splicing regulation in vitro to in vivo. The emerging transcription-folding-splicing paradigm is changing our understanding of RNA alternative splicing regulation. Here, we review the insights into the roles and mechanisms of RNA structures in alternative splicing and back-splicing, as well as how disruption of these structures affects alternative splicing and then leads to human diseases. This article is categorized under: RNA Processing > Splicing Regulation/Alternative Splicing RNA Structure and Dynamics > Influence of RNA Structure in Biological Systems.
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Affiliation(s)
- Bingbing Xu
- MOE Laboratory of Biosystems Homeostasis & Protection and Innovation Center for Cell Signaling Network, College of Life Sciences, Zhejiang University, Zhejiang, Hangzhou, China
| | - Yijun Meng
- College of Life and Environmental Sciences, Hangzhou Normal University, Zhejiang, Hangzhou, China
| | - Yongfeng Jin
- MOE Laboratory of Biosystems Homeostasis & Protection and Innovation Center for Cell Signaling Network, College of Life Sciences, Zhejiang University, Zhejiang, Hangzhou, China
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11
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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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12
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Development of novel macrocyclic small molecules that target CTG trinucleotide repeats. Bioorg Med Chem 2019; 27:2978-2984. [PMID: 31113691 DOI: 10.1016/j.bmc.2019.05.022] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Revised: 05/07/2019] [Accepted: 05/13/2019] [Indexed: 11/23/2022]
Abstract
We describe the molecular design, synthesis, and investigation of a series of acridine-triaminotriazine macrocycles that selectively bind to CTG trinucleotide repeats in DNA with minimal nonspecific binding. The limited conformational flexibility enforces the stacking of the triaminotriazine and acridine units. Isothermal titration calorimetry studies and Job plot analyses revealed that the ligands bound to d(CTG) mismatched sites. The acridine and triaminotriazine units were shown to intramolecularly π-stack in aqueous solutions. Compared to a noncyclic analog, the macrocycles showed an almost 10-fold lower cytotoxicity in HeLa cells and up to 4-fold higher transcription inhibition of d(CTG·CAG)74.
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13
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Mbarek A, Moussa G, Chain JL. Pharmaceutical Applications of Molecular Tweezers, Clefts and Clips. Molecules 2019; 24:molecules24091803. [PMID: 31075983 PMCID: PMC6539068 DOI: 10.3390/molecules24091803] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 05/03/2019] [Accepted: 05/07/2019] [Indexed: 12/25/2022] Open
Abstract
Synthetic acyclic receptors, composed of two arms connected with a spacer enabling molecular recognition, have been intensively explored in host-guest chemistry in the past decades. They fall into the categories of molecular tweezers, clefts and clips, depending on the geometry allowing the recognition of various guests. The advances in synthesis and mechanistic studies have pushed them forward to pharmaceutical applications, such as neurodegenerative disorders, infectious diseases, cancer, cardiovascular disease, diabetes, etc. In this review, we provide a summary of the synthetic molecular tweezers, clefts and clips that have been reported for pharmaceutical applications. Their structures, mechanism of action as well as in vitro and in vivo results are described. Such receptors were found to selectively bind biological guests, namely, nucleic acids, sugars, amino acids and proteins enabling their use as biosensors or therapeutics. Particularly interesting are dynamic molecular tweezers which are capable of controlled motion in response to an external stimulus. They proved their utility as imaging agents or in the design of controlled release systems. Despite some issues, such as stability, cytotoxicity or biocompatibility that still need to be addressed, it is obvious that molecular tweezers, clefts and clips are promising candidates for several incurable diseases as therapeutic agents, diagnostic or delivery tools.
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Affiliation(s)
- Amira Mbarek
- Gene Delivery Laboratory, Faculty of pharmacy, Université de Montréal, H3C 3J7, Montréal, Québec, Canada.
| | - Ghina Moussa
- Gene Delivery Laboratory, Faculty of pharmacy, Université de Montréal, H3C 3J7, Montréal, Québec, Canada.
| | - Jeanne Leblond Chain
- Gene Delivery Laboratory, Faculty of pharmacy, Université de Montréal, H3C 3J7, Montréal, Québec, Canada.
- Univ. Bordeaux, ARNA Laboratory, F-33016 Bordeaux, France.
- INSERM U1212, CNRS UMR 5320, ARNA Laboratory, F-33016 Bordeaux, France.
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14
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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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15
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López-Morató M, Brook JD, Wojciechowska M. Small Molecules Which Improve Pathogenesis of Myotonic Dystrophy Type 1. Front Neurol 2018; 9:349. [PMID: 29867749 PMCID: PMC5968088 DOI: 10.3389/fneur.2018.00349] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 04/30/2018] [Indexed: 12/30/2022] Open
Abstract
Myotonic dystrophy type 1 (DM1) is the most common muscular dystrophy in adults for which there is currently no treatment. The pathogenesis of this autosomal dominant disorder is associated with the expansion of CTG repeats in the 3'-UTR of the DMPK gene. DMPK transcripts with expanded CUG repeats (CUGexpDMPK) are retained in the nucleus forming multiple discrete foci, and their presence triggers a cascade of toxic events. Thus far, most research emphasis has been on interactions of CUGexpDMPK with the muscleblind-like (MBNL) family of splicing factors. These proteins are sequestered by the expanded CUG repeats of DMPK RNA leading to their functional depletion. As a consequence, abnormalities in many pathways of RNA metabolism, including alternative splicing, are detected in DM1. To date, in vitro and in vivo efforts to develop therapeutic strategies for DM1 have mostly been focused on targeting CUGexpDMPK via reducing their expression and/or preventing interactions with MBNL1. Antisense oligonucleotides targeted to the CUG repeats in the DMPK transcripts are of particular interest due to their potential capacity to discriminate between mutant and normal transcripts. However, a growing number of reports describe alternative strategies using small molecule chemicals acting independently of a direct interaction with CUGexpDMPK. In this review, we summarize current knowledge about these chemicals and we describe the beneficial effects they caused in different DM1 experimental models. We also present potential mechanisms of action of these compounds and pathways they affect which could be considered for future therapeutic interventions in DM1.
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Affiliation(s)
- Marta López-Morató
- Queen’s Medical Centre, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - John David Brook
- Queen’s Medical Centre, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Marzena Wojciechowska
- Queen’s Medical Centre, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
- Polish Academy of Sciences, Department of Molecular Genetics, Institute of Bioorganic Chemistry, Poznan, Poland
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16
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Affinity capillary electrophoresis for identification of active drug candidates in myotonic dystrophy type 1. Anal Bioanal Chem 2018; 410:4495-4507. [DOI: 10.1007/s00216-018-1107-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2018] [Revised: 03/16/2018] [Accepted: 04/24/2018] [Indexed: 12/31/2022]
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17
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Konieczny P, Selma-Soriano E, Rapisarda AS, Fernandez-Costa JM, Perez-Alonso M, Artero R. Myotonic dystrophy: candidate small molecule therapeutics. Drug Discov Today 2017; 22:1740-1748. [PMID: 28780071 DOI: 10.1016/j.drudis.2017.07.011] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 06/14/2017] [Accepted: 07/25/2017] [Indexed: 01/01/2023]
Abstract
Myotonic dystrophy type 1 (DM1) is a rare multisystemic neuromuscular disorder caused by expansion of CTG trinucleotide repeats in the noncoding region of the DMPK gene. Mutant DMPK transcripts are toxic and alter gene expression at several levels. Chiefly, the secondary structure formed by CUGs has a strong propensity to capture and retain proteins, like those of the muscleblind-like (MBNL) family. Sequestered MBNL proteins cannot then fulfill their normal functions. Many therapeutic approaches have been explored to reverse these pathological consequences. Here, we review the myriad of small molecules that have been proposed for DM1, including examples obtained from computational rational design, HTS, drug repurposing, and therapeutic gene modulation.
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Affiliation(s)
- Piotr Konieczny
- Department of Genetics and Interdisciplinary Research Structure for Biotechnology and Biomedicine (ERI BIOTECMED), Universitat de València, Valencia, Spain; Translational Genomics Group, Incliva Health Research Institute, Valencia, Spain; Joint Unit Incliva-CIPF, Valencia, Spain
| | - Estela Selma-Soriano
- Department of Genetics and Interdisciplinary Research Structure for Biotechnology and Biomedicine (ERI BIOTECMED), Universitat de València, Valencia, Spain; Translational Genomics Group, Incliva Health Research Institute, Valencia, Spain; Joint Unit Incliva-CIPF, Valencia, Spain
| | - Anna S Rapisarda
- Department of Genetics and Interdisciplinary Research Structure for Biotechnology and Biomedicine (ERI BIOTECMED), Universitat de València, Valencia, Spain; Translational Genomics Group, Incliva Health Research Institute, Valencia, Spain; Joint Unit Incliva-CIPF, Valencia, Spain
| | - Juan M Fernandez-Costa
- Department of Genetics and Interdisciplinary Research Structure for Biotechnology and Biomedicine (ERI BIOTECMED), Universitat de València, Valencia, Spain; Translational Genomics Group, Incliva Health Research Institute, Valencia, Spain; Joint Unit Incliva-CIPF, Valencia, Spain
| | - Manuel Perez-Alonso
- Department of Genetics and Interdisciplinary Research Structure for Biotechnology and Biomedicine (ERI BIOTECMED), Universitat de València, Valencia, Spain; Translational Genomics Group, Incliva Health Research Institute, Valencia, Spain; Joint Unit Incliva-CIPF, Valencia, Spain
| | - Ruben Artero
- Department of Genetics and Interdisciplinary Research Structure for Biotechnology and Biomedicine (ERI BIOTECMED), Universitat de València, Valencia, Spain; Translational Genomics Group, Incliva Health Research Institute, Valencia, Spain; Joint Unit Incliva-CIPF, Valencia, Spain.
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18
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Mao J, DeSantis C, Bong D. Small Molecule Recognition Triggers Secondary and Tertiary Interactions in DNA Folding and Hammerhead Ribozyme Catalysis. J Am Chem Soc 2017; 139:9815-9818. [PMID: 28691825 DOI: 10.1021/jacs.7b05448] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We have identified tris(2-aminoethyl)amine (tren)-derived scaffolds with two (t2M) or four (t4M) melamine rings that can target oligo T/U domains in DNA/RNA. Unstructured T-rich DNAs cooperatively fold with the tren derivatives to form hairpin-like structures. Both t2M and t4M act as functional switches in a family of hammerhead ribozymes deactivated by stem or loop replacement with a U-rich sequence. Catalysis of bond scission in these hammerhead ribozymes could be restored by putative t2M/t4M refolding of stem secondary structure or tertiary bridging interactions between loop and stem. The simplicity of the t2M/t4M binding site enables programming of allostery in RNAs, recoding oligo-U domains as potential sites for secondary structure or tertiary contact. In combination with a facile and general method for installation of the t2M motif on primary amines, the method described herein streamlines design of synthetic allosteric riboswitches and small molecule-nucleic acid complexes.
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Affiliation(s)
- Jie Mao
- Department of Chemistry and Biochemistry, The Ohio State University , 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Chris DeSantis
- Department of Chemistry and Biochemistry, The Ohio State University , 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Dennis Bong
- Department of Chemistry and Biochemistry, The Ohio State University , 100 West 18th Avenue, Columbus, Ohio 43210, United States
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19
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González ÀL, Konieczny P, Llamusi B, Delgado-Pinar E, Borrell JI, Teixidó J, García-España E, Pérez-Alonso M, Estrada-Tejedor R, Artero R. In silico discovery of substituted pyrido[2,3-d]pyrimidines and pentamidine-like compounds with biological activity in myotonic dystrophy models. PLoS One 2017; 12:e0178931. [PMID: 28582438 PMCID: PMC5459475 DOI: 10.1371/journal.pone.0178931] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 05/22/2017] [Indexed: 12/24/2022] Open
Abstract
Myotonic dystrophy type 1 (DM1) is a rare multisystemic disorder associated with an expansion of CUG repeats in mutant DMPK (dystrophia myotonica protein kinase) transcripts; the main effect of these expansions is the induction of pre-mRNA splicing defects by sequestering muscleblind-like family proteins (e.g. MBNL1). Disruption of the CUG repeats and the MBNL1 protein complex has been established as the best therapeutic approach for DM1, hence two main strategies have been proposed: targeted degradation of mutant DMPK transcripts and the development of CUG-binding molecules that prevent MBNL1 sequestration. Herein, suitable CUG-binding small molecules were selected using in silico approaches such as scaffold analysis, similarity searching, and druggability analysis. We used polarization assays to confirm the CUG repeat binding in vitro for a number of candidate compounds, and went on to evaluate the biological activity of the two with the strongest affinity for CUG repeats (which we refer to as compounds 1–2 and 2–5) in DM1 mutant cells and Drosophila DM1 models with an impaired locomotion phenotype. In particular, 1–2 and 2–5 enhanced the levels of free MBNL1 in patient-derived myoblasts in vitro and greatly improved DM1 fly locomotion in climbing assays. This work provides new computational approaches for rational large-scale virtual screens of molecules that selectively recognize CUG structures. Moreover, it contributes valuable knowledge regarding two compounds with desirable biological activity in DM1 models.
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Affiliation(s)
- Àlex L. González
- Grup d’Enginyeria Molecular (GEM), Institut Químic de Sarrià (IQS)–Universitat Ramon Llull (URL), Barcelona, Catalonia, Spain
| | - Piotr Konieczny
- Translational Genomics Group, Incliva Health Research Institute, Valencia, Spain
- Department of Genetics and Interdisciplinary Research Structure for Biotechnology and Biomedicine (ERI BIOTECMED), University of Valencia, Valencia, Spain
- Incliva-CIPF joint unit, Valencia, Spain
| | - Beatriz Llamusi
- Translational Genomics Group, Incliva Health Research Institute, Valencia, Spain
- Department of Genetics and Interdisciplinary Research Structure for Biotechnology and Biomedicine (ERI BIOTECMED), University of Valencia, Valencia, Spain
- Incliva-CIPF joint unit, Valencia, Spain
| | | | - José I. Borrell
- Grup d’Enginyeria Molecular (GEM), Institut Químic de Sarrià (IQS)–Universitat Ramon Llull (URL), Barcelona, Catalonia, Spain
| | - Jordi Teixidó
- Grup d’Enginyeria Molecular (GEM), Institut Químic de Sarrià (IQS)–Universitat Ramon Llull (URL), Barcelona, Catalonia, Spain
| | | | - Manuel Pérez-Alonso
- Translational Genomics Group, Incliva Health Research Institute, Valencia, Spain
- Department of Genetics and Interdisciplinary Research Structure for Biotechnology and Biomedicine (ERI BIOTECMED), University of Valencia, Valencia, Spain
- Incliva-CIPF joint unit, Valencia, Spain
| | - Roger Estrada-Tejedor
- Grup d’Enginyeria Molecular (GEM), Institut Químic de Sarrià (IQS)–Universitat Ramon Llull (URL), Barcelona, Catalonia, Spain
- * E-mail:
| | - Rubén Artero
- Translational Genomics Group, Incliva Health Research Institute, Valencia, Spain
- Department of Genetics and Interdisciplinary Research Structure for Biotechnology and Biomedicine (ERI BIOTECMED), University of Valencia, Valencia, Spain
- Incliva-CIPF joint unit, Valencia, Spain
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20
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Faulty RNA splicing: consequences and therapeutic opportunities in brain and muscle disorders. Hum Genet 2017; 136:1215-1235. [DOI: 10.1007/s00439-017-1802-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 04/13/2017] [Indexed: 12/12/2022]
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21
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Urbanek MO, Fiszer A, Krzyzosiak WJ. Reduction of Huntington's Disease RNA Foci by CAG Repeat-Targeting Reagents. Front Cell Neurosci 2017; 11:82. [PMID: 28400719 PMCID: PMC5368221 DOI: 10.3389/fncel.2017.00082] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 03/09/2017] [Indexed: 12/14/2022] Open
Abstract
In several human polyglutamine diseases caused by expansions of CAG repeats in the coding sequence of single genes, mutant transcripts are detained in nuclear RNA foci. In polyglutamine disorders, unlike other repeat-associated diseases, both RNA and proteins exert pathogenic effects; therefore, decreases of both RNA and protein toxicity need to be addressed in proposed treatments. A variety of oligonucleotide-based therapeutic approaches have been developed for polyglutamine diseases, but concomitant assays for RNA foci reduction are lacking. Here, we show that various types of oligonucleotide-based reagents affect RNA foci number in Huntington’s disease cells. We analyzed the effects of reagents targeting either CAG repeat tracts or specific HTT sequences in fibroblasts derived from patients. We tested reagents that either acted as translation blockers or triggered mRNA degradation via the RNA interference pathway or RNase H activation. We also analyzed the effect of chemical modifications of CAG repeat-targeting siRNAs on their efficiency in the foci decline. Our results suggest that the decrease of RNA foci number may be considered as a readout of treatment outcomes for oligonucleotide reagents.
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Affiliation(s)
- Martyna O Urbanek
- Department of Molecular Biomedicine, Institute of Bioorganic Chemistry Polish Academy of Sciences Poznan, Poland
| | - Agnieszka Fiszer
- Department of Molecular Biomedicine, Institute of Bioorganic Chemistry Polish Academy of Sciences Poznan, Poland
| | - Wlodzimierz J Krzyzosiak
- Department of Molecular Biomedicine, Institute of Bioorganic Chemistry Polish Academy of Sciences Poznan, Poland
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22
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Velagapudi SP, Luo Y, Tran T, Haniff HS, Nakai Y, Fallahi M, Martinez GJ, Childs-Disney JL, Disney MD. Defining RNA-Small Molecule Affinity Landscapes Enables Design of a Small Molecule Inhibitor of an Oncogenic Noncoding RNA. ACS CENTRAL SCIENCE 2017; 3:205-216. [PMID: 28386598 PMCID: PMC5364451 DOI: 10.1021/acscentsci.7b00009] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Indexed: 05/03/2023]
Abstract
RNA drug targets are pervasive in cells, but methods to design small molecules that target them are sparse. Herein, we report a general approach to score the affinity and selectivity of RNA motif-small molecule interactions identified via selection. Named High Throughput Structure-Activity Relationships Through Sequencing (HiT-StARTS), HiT-StARTS is statistical in nature and compares input nucleic acid sequences to selected library members that bind a ligand via high throughput sequencing. The approach allowed facile definition of the fitness landscape of hundreds of thousands of RNA motif-small molecule binding partners. These results were mined against folded RNAs in the human transcriptome and identified an avid interaction between a small molecule and the Dicer nuclease-processing site in the oncogenic microRNA (miR)-18a hairpin precursor, which is a member of the miR-17-92 cluster. Application of the small molecule, Targapremir-18a, to prostate cancer cells inhibited production of miR-18a from the cluster, de-repressed serine/threonine protein kinase 4 protein (STK4), and triggered apoptosis. Profiling the cellular targets of Targapremir-18a via Chemical Cross-Linking and Isolation by Pull Down (Chem-CLIP), a covalent small molecule-RNA cellular profiling approach, and other studies showed specific binding of the compound to the miR-18a precursor, revealing broadly applicable factors that govern small molecule drugging of noncoding RNAs.
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Affiliation(s)
- Sai Pradeep Velagapudi
- Department
of Chemistry, Informatics Core, and Genomics Core, The Scripps
Research Institute, 130
Scripps Way, Jupiter, Florida 33458, United
States
| | - Yiling Luo
- Department
of Chemistry, Informatics Core, and Genomics Core, The Scripps
Research Institute, 130
Scripps Way, Jupiter, Florida 33458, United
States
| | - Tuan Tran
- Department
of Chemistry, Informatics Core, and Genomics Core, The Scripps
Research Institute, 130
Scripps Way, Jupiter, Florida 33458, United
States
| | - Hafeez S. Haniff
- Department
of Chemistry, Informatics Core, and Genomics Core, The Scripps
Research Institute, 130
Scripps Way, Jupiter, Florida 33458, United
States
| | - Yoshio Nakai
- Department
of Chemistry, Informatics Core, and Genomics Core, The Scripps
Research Institute, 130
Scripps Way, Jupiter, Florida 33458, United
States
| | - Mohammad Fallahi
- Department
of Chemistry, Informatics Core, and Genomics Core, The Scripps
Research Institute, 130
Scripps Way, Jupiter, Florida 33458, United
States
| | - Gustavo J. Martinez
- Department
of Chemistry, Informatics Core, and Genomics Core, The Scripps
Research Institute, 130
Scripps Way, Jupiter, Florida 33458, United
States
| | - Jessica L. Childs-Disney
- Department
of Chemistry, Informatics Core, and Genomics Core, The Scripps
Research Institute, 130
Scripps Way, Jupiter, Florida 33458, United
States
| | - Matthew D. Disney
- Department
of Chemistry, Informatics Core, and Genomics Core, The Scripps
Research Institute, 130
Scripps Way, Jupiter, Florida 33458, United
States
- E-mail:
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23
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Sato Y, Saito H, Aoki D, Teramae N, Nishizawa S. Lysine linkage in abasic site-binding ligand-thiazole orange conjugates for improved binding affinity to orphan nucleobases in DNA/RNA hybrids. Chem Commun (Camb) 2016; 52:14446-14449. [PMID: 27901527 DOI: 10.1039/c6cc07236d] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Introduction of lysine linkage in the conjugate between abasic site-binding ligands and thiazole orange significantly improved the binding affinity for target orphan adenine or uracil nucleobase in DNA/RNA hybrids.
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Affiliation(s)
- Yusuke Sato
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan.
| | - Hiroki Saito
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan.
| | - Daisuke Aoki
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan.
| | - Norio Teramae
- 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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24
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Kotera N, Granzhan A, Teulade-Fichou MP. Comparative study of affinity and selectivity of ligands targeting abasic and mismatch sites in DNA using a fluorescence-melting assay. Biochimie 2016; 128-129:133-7. [PMID: 27523781 DOI: 10.1016/j.biochi.2016.08.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 08/08/2016] [Indexed: 11/29/2022]
Abstract
Recently, several families of small-molecule ligands have been developed to selectively target DNA pairing defects, such as abasic sites and mismatched base pairs, with the aim to interfere with the DNA repair and the template function of the DNA. However, the affinity and selectivity (with respect to well-matched DNA) of these ligands has barely been evaluated in a systematic way. Herein, we report a comparative study of binding affinity and selectivity of a representative panel of 16 ligands targeting abasic sites and a T-T mismatch in DNA, using a fluorescence-monitored melting assay. We demonstrate that bisintercalator-type macrocyclic ligands are characterized by moderate affinity but exceptionally high selectivity with respect to well-matched DNA, whereas other reported ligands show either modest selectivity or rather low affinity in identical conditions.
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Affiliation(s)
- Naoko Kotera
- Institut Curie, PSL Research University, CNRS UMR9187, INSERM U1196, F-91405, Orsay, France; Université Paris Sud, Université Paris-Saclay, CNRS UMR9187, INSERM U1196, F-91405, Orsay, France
| | - Anton Granzhan
- Institut Curie, PSL Research University, CNRS UMR9187, INSERM U1196, F-91405, Orsay, France; Université Paris Sud, Université Paris-Saclay, CNRS UMR9187, INSERM U1196, F-91405, Orsay, France.
| | - Marie-Paule Teulade-Fichou
- Institut Curie, PSL Research University, CNRS UMR9187, INSERM U1196, F-91405, Orsay, France; Université Paris Sud, Université Paris-Saclay, CNRS UMR9187, INSERM U1196, F-91405, Orsay, France
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25
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Synthesis of 1H-pyrrolo[3,2-h]quinoline-8-amine derivatives that target CTG trinucleotide repeats. Bioorg Med Chem Lett 2016; 26:3761-4. [DOI: 10.1016/j.bmcl.2016.05.062] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2016] [Revised: 05/16/2016] [Accepted: 05/21/2016] [Indexed: 01/03/2023]
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26
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Bai Y, Nguyen L, Song Z, Peng S, Lee J, Zheng N, Kapoor I, Hagler LD, Cai K, Cheng J, Chan HYE, Zimmerman SC. Integrating Display and Delivery Functionality with a Cell Penetrating Peptide Mimic as a Scaffold for Intracellular Multivalent Multitargeting. J Am Chem Soc 2016; 138:9498-507. [DOI: 10.1021/jacs.6b03697] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
| | | | | | - Shaohong Peng
- Laboratory
of Drosophila Research and School of Life Sciences, The Chinese University of Hong Kong,
Shatin, New Territories, Hong Kong SAR, China
| | | | | | | | | | | | | | - H. Y. Edwin Chan
- Laboratory
of Drosophila Research and School of Life Sciences, The Chinese University of Hong Kong,
Shatin, New Territories, Hong Kong SAR, China
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27
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Luu LM, Nguyen L, Peng S, Lee J, Lee HY, Wong CH, Hergenrother PJ, Chan HYE, Zimmerman SC. A Potent Inhibitor of Protein Sequestration by Expanded Triplet (CUG) Repeats that Shows Phenotypic Improvements in a Drosophila Model of Myotonic Dystrophy. ChemMedChem 2016; 11:1428-35. [PMID: 27245480 DOI: 10.1002/cmdc.201600081] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Revised: 04/29/2016] [Indexed: 11/09/2022]
Abstract
Myotonic dystrophy is the most common form of adult-onset muscular dystrophy, originating in a CTG repeat expansion in the DMPK gene. The expanded CUG transcript sequesters MBNL1, a key regulator of alternative splicing, leading to the misregulation of numerous pre-mRNAs. We report an RNA-targeted agent as a possible lead compound for the treatment of myotonic dystrophy type 1 (DM1) that reveals both the promise and challenges for this type of small-molecule approach. The agent is a potent inhibitor of the MBNL1-rCUG complex with an inhibition constant (Ki ) of 25±8 nm, and is also relatively nontoxic to HeLa cells, able to dissolve nuclear foci, and correct the insulin receptor splicing defect in DM1 model cells. Moreover, treatment with this compound improves two separate disease phenotypes in a Drosophila model of DM1: adult external eye degeneration and larval crawling defect. However, the compound has a relatively low maximum tolerated dose in mice, and its cell uptake may be limited, providing insight into directions for future development.
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Affiliation(s)
- Long M Luu
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave., Urbana, IL, 61801, USA
| | - Lien Nguyen
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave., Urbana, IL, 61801, USA
| | - Shaohong Peng
- Laboratory of Drosophila Research and School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, P.R. China
| | - JuYeon Lee
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave., Urbana, IL, 61801, USA
| | - Hyang Yeon Lee
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave., Urbana, IL, 61801, USA
| | - Chun-Ho Wong
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave., Urbana, IL, 61801, USA
| | - Paul J Hergenrother
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave., Urbana, IL, 61801, USA
| | - H Y Edwin Chan
- Laboratory of Drosophila Research and School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, P.R. China.
| | - Steven C Zimmerman
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave., Urbana, IL, 61801, USA.
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Zimmerman SC. A journey in bioinspired supramolecular chemistry: from molecular tweezers to small molecules that target myotonic dystrophy. Beilstein J Org Chem 2016; 12:125-38. [PMID: 26877815 PMCID: PMC4734311 DOI: 10.3762/bjoc.12.14] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 01/06/2016] [Indexed: 12/02/2022] Open
Abstract
This review summarizes part of the author’s research in the area of supramolecular chemistry, beginning with his early life influences and early career efforts in molecular recognition, especially molecular tweezers. Although designed to complex DNA, these hosts proved more applicable to the field of host–guest chemistry. This early experience and interest in intercalation ultimately led to the current efforts to develop small molecule therapeutic agents for myotonic dystrophy using a rational design approach that heavily relies on principles of supramolecular chemistry. How this work was influenced by that of others in the field and the evolution of each area of research is highlighted with selected examples.
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Affiliation(s)
- Steven C Zimmerman
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
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29
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Urbanek MO, Krzyzosiak WJ. RNA FISH for detecting expanded repeats in human diseases. Methods 2015; 98:115-123. [PMID: 26615955 DOI: 10.1016/j.ymeth.2015.11.017] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Revised: 11/18/2015] [Accepted: 11/21/2015] [Indexed: 12/14/2022] Open
Abstract
RNA fluorescence in situ hybridization (FISH) is a widely used technique for detecting transcripts in fixed cells and tissues. Many variants of RNA FISH have been proposed to increase signal strength, resolution and target specificity. The current variants of this technique facilitate the detection of the subcellular localization of transcripts at a single molecule level. Among the applications of RNA FISH are studies on nuclear RNA foci in diseases resulting from the expansion of tri-, tetra-, penta- and hexanucleotide repeats present in different single genes. The partial or complete retention of mutant transcripts forming RNA aggregates within the nucleoplasm has been shown in multiple cellular disease models and in the tissues of patients affected with these atypical mutations. Relevant diseases include, among others, myotonic dystrophy type 1 (DM1) with CUG repeats, Huntington's disease (HD) and spinocerebellar ataxia type 3 (SCA3) with CAG repeats, fragile X-associated tremor/ataxia syndrome (FXTAS) with CGG repeats, myotonic dystrophy type 2 (DM2) with CCUG repeats, amyotrophic lateral sclerosis/frontotemporal dementia (ALS/FTD) with GGGGCC repeats and spinocerebellar ataxia type 32 (SCA32) with GGCCUG. In this article, we summarize the results obtained with FISH to examine RNA nuclear inclusions. We provide a detailed protocol for detecting RNAs containing expanded CAG and CUG repeats in different cellular models, including fibroblasts, lymphoblasts, induced pluripotent stem cells and murine and human neuronal progenitors. We also present the results of the first single-molecule FISH application in a cellular model of polyglutamine disease.
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Affiliation(s)
- Martyna O Urbanek
- Department of Molecular Biomedicine, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14 Str., 61-704 Poznan, Poland
| | - Wlodzimierz J Krzyzosiak
- Department of Molecular Biomedicine, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14 Str., 61-704 Poznan, Poland.
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Abstract
The human transcriptome is composed of a vast RNA population that undergoes further diversification by splicing. Detecting specific splice sites in this large sequence pool is the responsibility of the major and minor spliceosomes in collaboration with numerous splicing factors. This complexity makes splicing susceptible to sequence polymorphisms and deleterious mutations. Indeed, RNA mis-splicing underlies a growing number of human diseases with substantial societal consequences. Here, we provide an overview of RNA splicing mechanisms followed by a discussion of disease-associated errors, with an emphasis on recently described mutations that have provided new insights into splicing regulation. We also discuss emerging strategies for splicing-modulating therapy.
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Affiliation(s)
- Marina M Scotti
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, Florida 32610-3610 USA
| | - Maurice S Swanson
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, Florida 32610-3610 USA
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31
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Nguyen L, Luu LM, Peng S, Serrano JF, Chan HYE, Zimmerman SC. Rationally designed small molecules that target both the DNA and RNA causing myotonic dystrophy type 1. J Am Chem Soc 2015; 137:14180-9. [PMID: 26473464 DOI: 10.1021/jacs.5b09266] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Single-agent, single-target therapeutic approaches are often limited by a complex disease pathobiology. We report rationally designed, multi-target agents for myotonic dystrophy type 1 (DM1). DM1 originates in an abnormal expansion of CTG repeats (CTG(exp)) in the DMPK gene. The resultant expanded CUG transcript (CUG(exp)) identified as a toxic agent sequesters important proteins, such as muscleblind-like proteins (MBNL), undergoes repeat-associated non-ATG (RAN) translation, and potentially causes microRNA dysregulation. We report rationally designed small molecules that target the DM1 pathobiology in vitro in three distinct ways by acting simultaneously as transcription inhibitors, by inhibiting aberrant protein binding to the toxic RNA, and by acting as RNase mimics to degrade the toxic RNA. In vitro, the agents are shown to (1) bind CTG(exp) and inhibit formation of the CUG(exp) transcript, (2) bind CUG(exp) and inhibit sequestration of MBNL1, and (3) cleave CUG(exp) in an RNase-like manner. The most potent compounds are capable of reducing the levels of CUG(exp) in DM1 model cells, and one reverses two separate CUG(exp)-induced phenotypes in a DM1 Drosophila model.
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Affiliation(s)
- Lien Nguyen
- Department of Chemistry, University of Illinois at Urbana-Champaign , 600 South Mathews Avenue, Urbana, Illinois 61801, United States
| | - Long M Luu
- Department of Chemistry, University of Illinois at Urbana-Champaign , 600 South Mathews Avenue, Urbana, Illinois 61801, United States
| | - Shaohong Peng
- Laboratory of Drosophila Research and School of Life Sciences, The Chinese University of Hong Kong , Shatin N.T., Hong Kong, SAR
| | - Julio F Serrano
- Department of Chemistry, University of Illinois at Urbana-Champaign , 600 South Mathews Avenue, Urbana, Illinois 61801, United States
| | - H Y Edwin Chan
- Laboratory of Drosophila Research and School of Life Sciences, The Chinese University of Hong Kong , Shatin N.T., Hong Kong, SAR
| | - Steven C Zimmerman
- Department of Chemistry, University of Illinois at Urbana-Champaign , 600 South Mathews Avenue, Urbana, Illinois 61801, United States
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32
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Childs-Disney JL, Disney MD. Approaches to Validate and Manipulate RNA Targets with Small Molecules in Cells. Annu Rev Pharmacol Toxicol 2015; 56:123-40. [PMID: 26514201 DOI: 10.1146/annurev-pharmtox-010715-103910] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
RNA has become an increasingly important target for therapeutic interventions and for chemical probes that dissect and manipulate its cellular function. Emerging targets include human RNAs that have been shown to directly cause cancer, metabolic disorders, and genetic disease. In this review, we describe various routes to obtain bioactive compounds that target RNA, with a particular emphasis on the development of small molecules. We use these cases to describe approaches that are being developed for target validation, which include target-directed cleavage, classic pull-down experiments, and covalent cross-linking. Thus, tools are available to design small molecules to target RNA and to identify the cellular RNAs that are their targets.
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Affiliation(s)
| | - Matthew D Disney
- Department of Chemistry, The Scripps Research Institute, Jupiter, Florida 33458; ,
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33
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Siboni RB, Bodner MJ, Khalifa MM, Docter AG, Choi JY, Nakamori M, Haley MM, Berglund JA. Biological Efficacy and Toxicity of Diamidines in Myotonic Dystrophy Type 1 Models. J Med Chem 2015; 58:5770-80. [PMID: 26103061 PMCID: PMC4972181 DOI: 10.1021/acs.jmedchem.5b00356] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Myotonic dystrophy type 1 (DM1) is a disease characterized by errors in alternative splicing, or "mis-splicing". The causative agent of mis-splicing in DM1 is an inherited CTG repeat expansion located in the 3' untranslated region of the DM protein kinase gene. When transcribed, CUG repeat expansion RNA sequesters muscleblind-like (MBNL) proteins, which constitute an important family of alternative splicing regulators. Sequestration of MBNL proteins results in the mis-splicing of its regulated transcripts. Previous work has demonstrated that pentamidine, a diamidine which is currently FDA-approved as an antiparasitic agent, was able to partially reverse mis-splicing in multiple DM1 models, albeit at toxic concentrations. In this study, we characterized a series of pentamidine analogues to determine their ability to reverse mis-splicing and their toxicity in vivo. Experiments in cell and mouse models demonstrated that compound 13, also known as furamidine, effectively reversed mis-splicing with equal efficacy and reduced toxicity compared to pentamidine.
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Affiliation(s)
| | | | | | | | | | - Masayuki Nakamori
- §Department of Neurology, University of Osaka Graduate School of Medicine, Osaka 565-0871, Japan
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Abstract
RNAs adopt diverse folded structures that are essential for function and thus play critical roles in cellular biology. A striking example of this is the ribosome, a complex, three-dimensionally folded macromolecular machine that orchestrates protein synthesis. Advances in RNA biochemistry, structural and molecular biology, and bioinformatics have revealed other non-coding RNAs whose functions are dictated by their structure. It is not surprising that aberrantly folded RNA structures contribute to disease. In this Review, we provide a brief introduction into RNA structural biology and then describe how RNA structures function in cells and cause or contribute to neurological disease. Finally, we highlight successful applications of rational design principles to provide chemical probes and lead compounds targeting structured RNAs. Based on several examples of well-characterized RNA-driven neurological disorders, we demonstrate how designed small molecules can facilitate the study of RNA dysfunction, elucidating previously unknown roles for RNA in disease, and provide lead therapeutics.
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Affiliation(s)
- Viachaslau Bernat
- 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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35
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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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36
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Chau A, Kalsotra A. Developmental insights into the pathology of and therapeutic strategies for DM1: Back to the basics. Dev Dyn 2015; 244:377-90. [PMID: 25504326 DOI: 10.1002/dvdy.24240] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 11/25/2014] [Accepted: 11/27/2014] [Indexed: 12/25/2022] Open
Abstract
Myotonic Dystrophy type 1 (DM1), the most prevalent adult onset muscular dystrophy, is a trinucleotide repeat expansion disease caused by CTG expansion in the 3'-UTR of DMPK gene. This expansion results in the expression of toxic gain-of-function RNA that forms ribonuclear foci and disrupts normal activities of RNA-binding proteins belonging to the MBNL and CELF families. Changes in alternative splicing, translation, localization, and mRNA stability due to sequestration of MBNL proteins and up-regulation of CELF1 are key to DM1 pathology. However, recent discoveries indicate that pathogenic mechanisms of DM1 involves many other factors as well, including repeat associated translation, activation of PKC-dependent signaling pathway, aberrant polyadenylation, and microRNA deregulation. Expression of the toxic repeat RNA culminates in the developmental remodeling of the transcriptome, which produces fetal isoforms of proteins that are unable to fulfill the physiological requirements of adult tissues. This review will describe advances in the understanding of DM1 pathogenesis as well as current therapeutic developments for DM1.
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Affiliation(s)
- Anthony Chau
- Department of Biochemistry, University of Illinois, Urbana-Champaign, Illinois; Department of Medical Biochemistry, University of Illinois, Urbana-Champaign, Illinois; Institute of Genomic Biology, University of Illinois, Urbana-Champaign, Illinois
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37
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deLorimier E, Coonrod LA, Copperman J, Taber A, Reister EE, Sharma K, Todd PK, Guenza MG, Berglund JA. Modifications to toxic CUG RNAs induce structural stability, rescue mis-splicing in a myotonic dystrophy cell model and reduce toxicity in a myotonic dystrophy zebrafish model. Nucleic Acids Res 2014; 42:12768-78. [PMID: 25303993 PMCID: PMC4227782 DOI: 10.1093/nar/gku941] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
CUG repeat expansions in the 3′ UTR of dystrophia myotonica protein kinase (DMPK) cause myotonic dystrophy type 1 (DM1). As RNA, these repeats elicit toxicity by sequestering splicing proteins, such as MBNL1, into protein–RNA aggregates. Structural studies demonstrate that CUG repeats can form A-form helices, suggesting that repeat secondary structure could be important in pathogenicity. To evaluate this hypothesis, we utilized structure-stabilizing RNA modifications pseudouridine (Ψ) and 2′-O-methylation to determine if stabilization of CUG helical conformations affected toxicity. CUG repeats modified with Ψ or 2′-O-methyl groups exhibited enhanced structural stability and reduced affinity for MBNL1. Molecular dynamics and X-ray crystallography suggest a potential water-bridging mechanism for Ψ-mediated CUG repeat stabilization. Ψ modification of CUG repeats rescued mis-splicing in a DM1 cell model and prevented CUG repeat toxicity in zebrafish embryos. This study indicates that the structure of toxic RNAs has a significant role in controlling the onset of neuromuscular diseases.
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Affiliation(s)
- Elaine deLorimier
- Department of Chemistry and Biochemistry, Institute of Molecular Biology, University of Oregon, Eugene, Oregon, USA
| | - Leslie A Coonrod
- Department of Chemistry and Biochemistry, Institute of Molecular Biology, University of Oregon, Eugene, Oregon, USA
| | - Jeremy Copperman
- Department of Chemistry and Biochemistry, Institute of Molecular Biology, University of Oregon, Eugene, Oregon, USA
| | - Alex Taber
- Department of Chemistry and Biochemistry, Institute of Molecular Biology, University of Oregon, Eugene, Oregon, USA
| | - Emily E Reister
- Department of Chemistry and Biochemistry, Institute of Molecular Biology, University of Oregon, Eugene, Oregon, USA
| | - Kush Sharma
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, USA
| | - Peter K Todd
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, USA
| | - Marina G Guenza
- Department of Chemistry and Biochemistry, Institute of Molecular Biology, University of Oregon, Eugene, Oregon, USA
| | - J Andrew Berglund
- Department of Chemistry and Biochemistry, Institute of Molecular Biology, University of Oregon, Eugene, Oregon, USA
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38
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Konieczny P, Stepniak-Konieczna E, Sobczak K. MBNL proteins and their target RNAs, interaction and splicing regulation. Nucleic Acids Res 2014; 42:10873-87. [PMID: 25183524 PMCID: PMC4176163 DOI: 10.1093/nar/gku767] [Citation(s) in RCA: 126] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Muscleblind-like (MBNL) proteins are key regulators of precursor and mature mRNA metabolism in mammals. Based on published and novel data, we explore models of tissue-specific MBNL interaction with RNA. We portray MBNL domains critical for RNA binding and splicing regulation, and the structure of MBNL's normal and pathogenic RNA targets, particularly in the context of myotonic dystrophy (DM), in which expanded CUG or CCUG repeat transcripts sequester several nuclear proteins including MBNLs. We also review the properties of MBNL/RNA complex, including recent data obtained from UV cross-linking and immunoprecipitation (CLIP-Seq), and discuss how this interaction shapes normal MBNL-dependent alternative splicing regulation. Finally, we review how this acquired knowledge about the pathogenic RNA structure and nature of MBNL sequestration can be translated into the design of therapeutic strategies against DM.
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Affiliation(s)
- Patryk Konieczny
- Department of Gene Expression, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Umultowska 89, 61-614 Poznan, Poland
| | - Ewa Stepniak-Konieczna
- Department of Gene Expression, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Umultowska 89, 61-614 Poznan, Poland
| | - Krzysztof Sobczak
- Department of Gene Expression, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Umultowska 89, 61-614 Poznan, Poland
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39
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Nguyen L, Lee J, Wong CH, Zimmerman SC. Small molecules that target the toxic RNA in myotonic dystrophy type 2. ChemMedChem 2014; 9:2455-62. [PMID: 24938413 DOI: 10.1002/cmdc.201402095] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Indexed: 12/19/2022]
Abstract
Myotonic dystrophy type 2 (DM2) is caused by an expansion of CCTG repeats in the zinc-finger protein gene (ZNF9). Transcribed CCUG repeats sequester muscleblind-like protein 1 (MBNL1), an important alternative splicing regulator, preventing its normal function, leading to the disease phenotype. We describe a series of ligands that disrupt the MBNL1-r(CCUG)n interaction as potential lead agents for developing DM2 therapeutics. A previously reported triaminopyrimidine-acridine conjugate was a moderate inhibitor in vitro, however it proved to be poorly water-soluble and not cell-permeable. To improve its therapeutic potential, the new set of ligands maintained the key triaminopyrimidine recognition unit but replaced the acridine intercalator with a bisamidinium groove binder. The optimized ligands exhibit low micromolar inhibition potency to MBNL1-r(CCUG)8. Importantly, the ligands are the first to show the ability to disrupt the MBNL1-r(CCUG)n foci in DM2 model cell culture and exhibit low cytotoxicity.
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Affiliation(s)
- Lien Nguyen
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave., Urbana, IL 61801 (USA)
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40
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Abstract
CNG repeats (where N denotes one of the four natural nucleotides) are abundant in the human genome. Their tendency to undergo expansion can lead to hereditary diseases known as TREDs (trinucleotide repeat expansion disorders). The toxic factor can be protein, if the abnormal gene is expressed, or the gene transcript, or both. The gene transcripts have attracted much attention in the biomedical community, but their molecular structures have only recently been investigated. Model RNA molecules comprising CNG repeats fold into long hairpins whose stems generally conform to an A-type helix, in which the non-canonical N-N pairs are flanked by C-G and G-C pairs. Each homobasic pair is accommodated in the helical context in a unique manner, with consequences for the local helical parameters, solvent structure, electrostatic potential and potential to interact with ligands. The detailed three-dimensional profiles of RNA CNG repeats can be used in screening of compound libraries for potential therapeutics and in structure-based drug design. Here is a brief survey of the CNG structures published to date.
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Affiliation(s)
- Agnieszka Kiliszek
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland
| | - Wojciech Rypniewski
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland
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41
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Wong CH, Nguyen L, Peh J, Luu LM, Sanchez J, Richardson SL, Tuccinardi T, Tsoi H, Chan WY, Chan HY, Baranger AM, Hergenrother PJ, Zimmerman SC. Targeting toxic RNAs that cause myotonic dystrophy type 1 (DM1) with a bisamidinium inhibitor. J Am Chem Soc 2014; 136:6355-61. [PMID: 24702247 PMCID: PMC4015652 DOI: 10.1021/ja5012146] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Indexed: 01/28/2023]
Abstract
A working hypothesis for the pathogenesis of myotonic dystrophy type 1 (DM1) involves the aberrant sequestration of an alternative splicing regulator, MBNL1, by expanded CUG repeats, r(CUG)(exp). It has been suggested that a reversal of the myotonia and potentially other symptoms of the DM1 disease can be achieved by inhibiting the toxic MBNL1-r(CUG)(exp) interaction. Using rational design, we discovered an RNA-groove binding inhibitor (ligand 3) that contains two triaminotriazine units connected by a bisamidinium linker. Ligand 3 binds r(CUG)12 with a low micromolar affinity (K(d) = 8 ± 2 μM) and disrupts the MBNL1-r(CUG)12 interaction in vitro (K(i) = 8 ± 2 μM). In addition, ligand 3 is cell and nucleus permeable, exhibits negligible toxicity to mammalian cells, dissolves MBNL1-r(CUG)(exp) ribonuclear foci, and restores misregulated splicing of IR and cTNT in a DM1 cell culture model. Importantly, suppression of r(CUG)(exp) RNA-induced toxicity in a DM1 Drosophila model was observed after treatment with ligand 3. These results suggest ligand 3 as a lead for the treatment of DM1.
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Affiliation(s)
- Chun-Ho Wong
- Department
of Chemistry, University of Illinois at
Urbana−Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United
States
| | - Lien Nguyen
- Department
of Chemistry, University of Illinois at
Urbana−Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United
States
| | - Jessie Peh
- Department
of Chemistry, University of Illinois at
Urbana−Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United
States
| | - Long M. Luu
- Department
of Chemistry, University of Illinois at
Urbana−Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United
States
| | - Jeannette
S. Sanchez
- Department
of Chemistry, University of Illinois at
Urbana−Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United
States
| | - Stacie L. Richardson
- Department
of Chemistry, University of Illinois at
Urbana−Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United
States
| | | | - Ho Tsoi
- Laboratory of Drosophila
Research and School of Life Sciences and School of Biomedical
Sciences, The Chinese University of Hong
Kong, Shatin, N.T., Hong Kong SAR, The People's Republic
of China
| | - Wood Yee Chan
- Laboratory of Drosophila
Research and School of Life Sciences and School of Biomedical
Sciences, The Chinese University of Hong
Kong, Shatin, N.T., Hong Kong SAR, The People's Republic
of China
| | - H. Y.
Edwin Chan
- Laboratory of Drosophila
Research and School of Life Sciences and School of Biomedical
Sciences, The Chinese University of Hong
Kong, Shatin, N.T., Hong Kong SAR, The People's Republic
of China
| | - Anne M. Baranger
- Department
of Chemistry, University of Illinois at
Urbana−Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United
States
| | - Paul J. Hergenrother
- Department
of Chemistry, University of Illinois at
Urbana−Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United
States
| | - Steven C. Zimmerman
- Department
of Chemistry, University of Illinois at
Urbana−Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United
States
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42
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Wojciechowska M, Taylor K, Sobczak K, Napierala M, Krzyzosiak WJ. Small molecule kinase inhibitors alleviate different molecular features of myotonic dystrophy type 1. RNA Biol 2014; 11:742-54. [PMID: 24824895 PMCID: PMC4156505 DOI: 10.4161/rna.28799] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Expandable (CTG)n repeats in the 3′ UTR of the DMPK gene are a cause of myotonic dystrophy type 1 (DM1), which leads to a toxic RNA gain-of-function disease. Mutant RNAs with expanded CUG repeats are retained in the nucleus and aggregate in discrete inclusions. These foci sequester splicing factors of the MBNL family and trigger upregulation of the CUGBP family of proteins resulting in the mis-splicing of their target transcripts. To date, many efforts to develop novel therapeutic strategies have been focused on disrupting the toxic nuclear foci and correcting aberrant alternative splicing via targeting mutant CUG repeats RNA; however, no effective treatment for DM1 is currently available. Herein, we present results of culturing of human DM1 myoblasts and fibroblasts with two small-molecule ATP-binding site-specific kinase inhibitors, C16 and C51, which resulted in the alleviation of the dominant-negative effects of CUG repeat expansion. Reversal of the DM1 molecular phenotype includes a reduction of the size and number of foci containing expanded CUG repeat transcripts, decreased steady-state levels of CUGBP1 protein, and consequent improvement of the aberrant alternative splicing of several pre-mRNAs misregulated in DM1.
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Affiliation(s)
- Marzena Wojciechowska
- Department of Molecular Biomedicine; Institute of Bioorganic Chemistry; Polish Academy of Sciences; Noskowskiego; Poznan, Poland
| | - Katarzyna Taylor
- Department of Gene Expression; Institute of Molecular Biology and Biotechnology; Adam Mickiewicz University; Umultowska 89; Poznan, Poland
| | - Krzysztof Sobczak
- Department of Gene Expression; Institute of Molecular Biology and Biotechnology; Adam Mickiewicz University; Umultowska 89; Poznan, Poland
| | - Marek Napierala
- Department of Biochemistry and Molecular Genetics and UAB Stem Cell Institute; University of Alabama at Birmingham; Birmingham, AL USA
| | - Wlodzimierz J Krzyzosiak
- Department of Molecular Biomedicine; Institute of Bioorganic Chemistry; Polish Academy of Sciences; Noskowskiego; Poznan, Poland
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43
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Granzhan A, Kotera N, Teulade-Fichou MP. Finding needles in a basestack: recognition of mismatched base pairs in DNA by small molecules. Chem Soc Rev 2014; 43:3630-65. [DOI: 10.1039/c3cs60455a] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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44
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Jahromi AH, Fu Y, Miller KA, Nguyen L, Luu LM, Baranger AM, Zimmerman SC. Developing bivalent ligands to target CUG triplet repeats, the causative agent of myotonic dystrophy type 1. J Med Chem 2013; 56:9471-9481. [PMID: 24188018 DOI: 10.1021/jm400794z] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An expanded CUG repeat transcript (CUG(exp)) is the causative agent of myotonic dystrophy type 1 (DM1) by sequestering muscleblind-like 1 protein (MBNL1), a regulator of alternative splicing. On the basis of a ligand (1) that was previously reported to be active in an in vitro assay, we present the synthesis of a small library containing 10 dimeric ligands (4-13) that differ in length, composition, and attachment point of the linking chain. The oligoamino linkers gave a greater gain in affinity for CUG RNA and were more effective when compared to oligoether linkers. The most potent in vitro ligand (9) was shown to be aqueous-soluble and both cell- and nucleus-permeable, displaying almost complete dispersion of MBNL1 ribonuclear foci in a DM1 cell model. Direct evidence for the bioactivity of 9 was observed in its ability to disperse ribonuclear foci in individual live DM1 model cells using time-lapse confocal fluorescence microscopy.
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Affiliation(s)
- Amin Haghighat Jahromi
- Center for Biophysics and Computational Biology, University of Illinois, Urbana, IL, USA.,Department of Chemistry, University of Illinois, Urbana, IL, USA
| | - Yuan Fu
- Department of Chemistry, University of Illinois, Urbana, IL, USA
| | - Kali A Miller
- Department of Chemistry, University of Illinois, Urbana, IL, USA
| | - Lien Nguyen
- Department of Chemistry, University of Illinois, Urbana, IL, USA
| | - Long M Luu
- Department of Chemistry, University of Illinois, Urbana, IL, USA
| | - Anne M Baranger
- Department of Chemistry, University of Illinois, Urbana, IL, USA
| | - Steven C Zimmerman
- Center for Biophysics and Computational Biology, University of Illinois, Urbana, IL, USA.,Department of Chemistry, University of Illinois, Urbana, IL, USA
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Artigas G, Marchán V. Synthesis of Janus compounds for the recognition of G-U mismatched nucleobase pairs. J Org Chem 2013; 78:10666-77. [PMID: 24087986 DOI: 10.1021/jo401684j] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The design and synthesis of two Janus-type heterocycles with the capacity to simultaneously recognize guanine and uracyl in G-U mismatched pairs through complementary hydrogen bond pairing is described. Both compounds were conveniently functionalized with a carboxylic function and efficiently attached to a tripeptide sequence by using solid-phase methodologies. Ligands based on the derivatization of such Janus compounds with a small aminoglycoside, neamine, and its guanidinylated analogue have been synthesized, and their interaction with Tau RNA has been investigated by using several biophysical techniques, including UV-monitored melting curves, fluorescence titration experiments, and (1)H NMR. The overall results indicated that Janus-neamine/guanidinoneamine showed some preference for the +3 mutated RNA sequence associated with the development of some tauopathies, although preliminary NMR studies have not confirmed binding to G-U pairs. Moreover, a good correlation has been found between the RNA binding affinity of such Janus-containing ligands and their ability to stabilize this secondary structure upon complexation.
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Affiliation(s)
- Gerard Artigas
- Departament de Química Orgànica, Facultat de Química, Universitat de Barcelona Martí i Franquès 1-11, E-08028 Barcelona, Spain
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Piao X, Xia X, Bong D. Bifacial peptide nucleic acid directs cooperative folding and assembly of binary, ternary, and quaternary DNA complexes. Biochemistry 2013; 52:6313-23. [PMID: 23964711 DOI: 10.1021/bi4008963] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report herein the structuring of single-stranded thymine-rich DNA sequences into peptide-DNA hairpin triplex structures via designed melamine-thymine nucleobase recognition. Melamine-displaying α-peptides were synthesized with the general form (EM*)n, where M* denotes a lysine residue side chain derivatized with melamine, a bifacial hydrogen bond complement for thymine. We have found that (EM*)n peptides, which we term bifacial peptide nucleic acid (bPNA), function as a noncovalent template for thymine-rich DNA tracts. Unstructured DNA of the general form dTnCmTn are bound to (EM*)n peptides and fold into cooperatively melting 1:1 bPNA-DNA hairpin complexes with dissociation constants in the submicromolar to low nanomolar range for n = 4-10. As the length of the interface (n) is decreased, the melting temperature of the bPNA-DNA complex drops significantly, though Kd increases are less substantial, suggestive of strong enthalpy-entropy compensation. This is borne out by differential scanning calorimetry analysis, which indicates enthalpically driven bPNA-DNA base-stacking that becomes markedly less exothermic as the recognition surface n decreases in size. The recognition interface tolerates a high number of "mismatches" and indicates half-site, or monofacial, recognition between melamine and thymine may occur if only 1 complementary nucleobase is available. Association correlates directly with fractional thymine content, with optimal binding when the number of T-T sites match the number of melamine units. Interestingly, when a DNA host has more T-T sites than melamine sites on bPNA, two or three bPNAs can bind to a single DNA, resulting in ternary and quaternary complexes that have higher thermal stability than the binary (1:1) bPNA-DNA complex, suggestive of cooperative multisite binding. In contrast, when two bPNAs of different lengths bind to the same DNA host, a ternary complex is formed with two melting transitions, corresponding to independent melting of each bPNA component from the complex. These data demonstrate that melamine-displaying bPNA recognize thymine-rich DNA in predictable and multifaceted ways that allow binding affinity, structure stability, and stoichiometry to be tuned through simple bPNA length modification and matching with DNA length. Synthetic bPNA structuring elements may be useful tools for biotechnology.
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Affiliation(s)
- Xijun Piao
- Department of Chemistry and Biochemistry, The Ohio State University , 100 West 18th Avenue, Columbus, Ohio 43210, United States
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