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Wang J, Gao G, Wang D. Developing AAV-delivered nonsense suppressor tRNAs for neurological disorders. Neurotherapeutics 2024; 21:e00391. [PMID: 38959711 PMCID: PMC11269797 DOI: 10.1016/j.neurot.2024.e00391] [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: 02/14/2024] [Revised: 05/29/2024] [Accepted: 06/19/2024] [Indexed: 07/05/2024] Open
Abstract
Adeno-associated virus (AAV)-based gene therapy is a clinical stage therapeutic modality for neurological disorders. A common genetic defect in myriad monogenic neurological disorders is nonsense mutations that account for about 11% of all human pathogenic mutations. Stop codon readthrough by suppressor transfer RNA (sup-tRNA) has long been sought as a potential gene therapy approach to target nonsense mutations, but hindered by inefficient in vivo delivery. The rapid advances in AAV delivery technology have not only powered gene therapy development but also enabled in vivo preclinical assessment of a range of nucleic acid therapeutics, such as sup-tRNA. Compared with conventional AAV gene therapy that delivers a transgene to produce therapeutic proteins, AAV-delivered sup-tRNA has several advantages, such as small gene sizes and operating within the endogenous gene expression regulation, which are important considerations for treating some neurological disorders. This review will first examine sup-tRNA designs and delivery by AAV vectors. We will then analyze how AAV-delivered sup-tRNA can potentially address some neurological disorders that are challenging to conventional gene therapy, followed by discussing available mouse models of neurological diseases for in vivo preclinical testing. Potential challenges for AAV-delivered sup-tRNA to achieve therapeutic efficacy and safety will also be discussed.
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Affiliation(s)
- Jiaming Wang
- Horae Gene Therapy Center, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA; Department of Microbiology and Physiological Systems, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
| | - Guangping Gao
- Horae Gene Therapy Center, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA; Department of Microbiology and Physiological Systems, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA.
| | - Dan Wang
- Horae Gene Therapy Center, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA; RNA Therapeutics Institute, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA.
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2
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Morais P, Zhang R, Yu YT. Therapeutic Nonsense Suppression Modalities: From Small Molecules to Nucleic Acid-Based Approaches. Biomedicines 2024; 12:1284. [PMID: 38927491 PMCID: PMC11201248 DOI: 10.3390/biomedicines12061284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2024] [Revised: 05/29/2024] [Accepted: 06/07/2024] [Indexed: 06/28/2024] Open
Abstract
Nonsense mutations are genetic mutations that create premature termination codons (PTCs), leading to truncated, defective proteins in diseases such as cystic fibrosis, neurofibromatosis type 1, Dravet syndrome, Hurler syndrome, Beta thalassemia, inherited bone marrow failure syndromes, Duchenne muscular dystrophy, and even cancer. These mutations can also trigger a cellular surveillance mechanism known as nonsense-mediated mRNA decay (NMD) that degrades the PTC-containing mRNA. The activation of NMD can attenuate the consequences of truncated, defective, and potentially toxic proteins in the cell. Since approximately 20% of all single-point mutations are disease-causing nonsense mutations, it is not surprising that this field has received significant attention, resulting in a remarkable advancement in recent years. In fact, since our last review on this topic, new examples of nonsense suppression approaches have been reported, namely new ways of promoting the translational readthrough of PTCs or inhibiting the NMD pathway. With this review, we update the state-of-the-art technologies in nonsense suppression, focusing on novel modalities with therapeutic potential, such as small molecules (readthrough agents, NMD inhibitors, and molecular glue degraders); antisense oligonucleotides; tRNA suppressors; ADAR-mediated RNA editing; targeted pseudouridylation; and gene/base editing. While these various modalities have significantly advanced in their development stage since our last review, each has advantages (e.g., ease of delivery and specificity) and disadvantages (manufacturing complexity and off-target effect potential), which we discuss here.
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Affiliation(s)
- Pedro Morais
- Drug Metabolism and Pharmacokinetics, Research and Development, Bayer Pharmaceuticals, 42113 Wuppertal, Germany
| | - Rui Zhang
- Center for RNA Biology, Department of Biochemistry and Biophysics, University of Rochester Medical Center, 601 Elmwood Avenue, Rochester, NY 14642, USA;
| | - Yi-Tao Yu
- Center for RNA Biology, Department of Biochemistry and Biophysics, University of Rochester Medical Center, 601 Elmwood Avenue, Rochester, NY 14642, USA;
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3
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Gemmati D, D’Aversa E, Antonica B, Grisafi M, Salvatori F, Pizzicotti S, Pellegatti P, Ciccone M, Moratelli S, Serino ML, Tisato V. Gene Dosage of F5 c.3481C>T Stop-Codon (p.R1161Ter) Switches the Clinical Phenotype from Severe Thrombosis to Recurrent Haemorrhage: Novel Hypotheses for Readthrough Strategy. Genes (Basel) 2024; 15:432. [PMID: 38674367 PMCID: PMC11050146 DOI: 10.3390/genes15040432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Revised: 03/25/2024] [Accepted: 03/27/2024] [Indexed: 04/28/2024] Open
Abstract
Inherited defects in the genes of blood coagulation essentially express the severity of the clinical phenotype that is directly correlated to the number of mutated alleles of the candidate leader gene (e.g., heterozygote vs. homozygote) and of possible additional coinherited traits. The F5 gene, which codes for coagulation factor V (FV), plays a two-faced role in the coagulation cascade, exhibiting both procoagulant and anticoagulant functions. Thus, defects in this gene can be predisposed to either bleeding or thrombosis. A Sanger sequence analysis detected a premature stop-codon in exon 13 of the F5 gene (c.3481C>T; p.R1161Ter) in several members of a family characterised by low circulating FV levels and contrasting clinical phenotypes. The propositus, a 29 y.o. male affected by recurrent haemorrhages, was homozygous for the F5 stop-codon and for the F5 c.1691G>A (p.R506Q; FV-Leiden) inherited from the heterozygous parents, which is suggestive of combined cis-segregation. The homozygous condition of the stop-codon completely abolished the F5 gene expression in the propositus (FV:Ag < 1%; FV:C < 1%; assessed by ELISA and PT-based one-stage clotting assay respectively), removing, in turn, any chance for FV-Leiden to act as a prothrombotic molecule. His father (57 y.o.), characterised by severe recurrent venous thromboses, underwent a complete molecular thrombophilic screening, revealing a heterozygous F2 G20210A defect, while his mother (56 y.o.), who was negative for further common coagulation defects, reported fully asymptomatic anamnesis. To dissect these conflicting phenotypes, we performed the ProC®Global (Siemens Helthineers) coagulation test aimed at assessing the global pro- and anticoagulant balance of each family member, investigating the responses to the activated protein C (APC) by means of an APC-sensitivity ratio (APC-sr). The propositus had an unexpectedly poor response to APC (APC-sr: 1.09; n.v. > 2.25), and his father and mother had an APC-sr of 1.5 and 2.0, respectively. Although ProC®Global prevalently detects the anticoagulant side of FV, the exceptionally low APC-sr of the propositus and his discordant severe-moderate haemorrhagic phenotype could suggest a residual expression of mutated FV p.506QQ through a natural readthrough or possible alternative splicing mechanisms. The coagulation pathway may be physiologically rebalanced through natural and induced strategies, and the described insights might be able to track the design of novel treatment approaches and rebalancing molecules.
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Affiliation(s)
- Donato Gemmati
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy
- University Strategic Centre for Studies on Gender Medicine, University of Ferrara, 44121 Ferrara, Italy
- Centre Haemostasis & Thrombosis, University of Ferrara, 44121 Ferrara, Italy
| | - Elisabetta D’Aversa
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy
| | - Bianca Antonica
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy
| | - Miriana Grisafi
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy
| | - Francesca Salvatori
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy
| | | | | | - Maria Ciccone
- Haematology Unit, Hospital-University of Ferrara, 44121 Ferrara, Italy
| | - Stefano Moratelli
- Centre Haemostasis & Thrombosis, University of Ferrara, 44121 Ferrara, Italy
| | - Maria Luisa Serino
- Centre Haemostasis & Thrombosis, University of Ferrara, 44121 Ferrara, Italy
| | - Veronica Tisato
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy
- University Strategic Centre for Studies on Gender Medicine, University of Ferrara, 44121 Ferrara, Italy
- Laboratory of Technology for Advanced Therapies (LTTA) Centre, University of Ferrara, 44121 Ferrara, Italy
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4
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Popova KB, Penchovsky R. General and Specific Cytotoxicity of Chimeric Antisense Oligonucleotides in Bacterial Cells and Human Cell Lines. Antibiotics (Basel) 2024; 13:122. [PMID: 38391508 PMCID: PMC10885958 DOI: 10.3390/antibiotics13020122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2023] [Revised: 01/21/2024] [Accepted: 01/24/2024] [Indexed: 02/24/2024] Open
Abstract
In the last two decades, antisense oligonucleotide technology has emerged as a promising approach to tackling various healthcare issues and diseases, such as antimicrobial resistance, cancer, and neurodegenerative diseases. Despite the numerous improvements in the structure and modifications of the antisense oligonucleotides (ASOs), there are still specific problems with their clinical efficacy and preclinical cytotoxicity results. To better understand the effects of the ASOs in this paper, we conducted many MTT assays to assess the general and specific cytotoxicity of four new chimeric ASOs in bacterial cells and human cell lines. We demonstrate the absence of inhibitory activity in the human pathogenic bacteria Staphylococcus aureus by non-specific ASOs. The pVEC-ASO1 and pVEC-ASO2 are designed to have no specific targets in S. aureus. They have only partial hybridization to the guanylate kinase mRNA. The pVEC-ASO3 targets UBA2 mRNA, a hallmark cancer pathology in MYC-driven cancer, while pVEC-ASO4 has no complementary sequences. We discovered some cytotoxicity of the non-specific ASOs in healthy and cancer human cell lines. The results are compared with two other ASOs, targeting specific mRNA in cancer cells. All ASOs are delivered into the cell via the cell-penetrating oligopeptide pVEC, which is attached to them. We draw a good correlation between the thermodynamic stability of ASO/target RNA and the toxicity effect in human cell lines. The data obtained signify the importance of thorough bioinformatic analysis and high specificity in designing and developing novel ASOs for safer therapeutic agents in clinical practice.
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Affiliation(s)
- Katya B Popova
- Laboratory of Synthetic Biology and Bioinformatics, Faculty of Biology, Sofia University "St. Kliment Ohridski", 8 Dragan Tzankov Blvd., 1164 Sofia, Bulgaria
- Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, 1784 Sofia, Bulgaria
| | - Robert Penchovsky
- Laboratory of Synthetic Biology and Bioinformatics, Faculty of Biology, Sofia University "St. Kliment Ohridski", 8 Dragan Tzankov Blvd., 1164 Sofia, Bulgaria
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Wittenstein A, Caspi M, Rippin I, Elroy-Stein O, Eldar-Finkelman H, Thoms S, Rosin-Arbesfeld R. Nonsense mutation suppression is enhanced by targeting different stages of the protein synthesis process. PLoS Biol 2023; 21:e3002355. [PMID: 37943958 PMCID: PMC10684085 DOI: 10.1371/journal.pbio.3002355] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 11/28/2023] [Accepted: 09/29/2023] [Indexed: 11/12/2023] Open
Abstract
The introduction of premature termination codons (PTCs), as a result of splicing defects, insertions, deletions, or point mutations (also termed nonsense mutations), lead to numerous genetic diseases, ranging from rare neuro-metabolic disorders to relatively common inheritable cancer syndromes and muscular dystrophies. Over the years, a large number of studies have demonstrated that certain antibiotics and other synthetic molecules can act as PTC suppressors by inducing readthrough of nonsense mutations, thereby restoring the expression of full-length proteins. Unfortunately, most PTC readthrough-inducing agents are toxic, have limited effects, and cannot be used for therapeutic purposes. Thus, further efforts are required to improve the clinical outcome of nonsense mutation suppressors. Here, by focusing on enhancing readthrough of pathogenic nonsense mutations in the adenomatous polyposis coli (APC) tumor suppressor gene, we show that disturbing the protein translation initiation complex, as well as targeting other stages of the protein translation machinery, enhances both antibiotic and non-antibiotic-mediated readthrough of nonsense mutations. These findings strongly increase our understanding of the mechanisms involved in nonsense mutation readthrough and facilitate the development of novel therapeutic targets for nonsense suppression to restore protein expression from a large variety of disease-causing mutated transcripts.
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Affiliation(s)
- Amnon Wittenstein
- Department of Clinical Microbiology and Immunology, Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Michal Caspi
- Department of Clinical Microbiology and Immunology, Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Ido Rippin
- The Department of Human Molecular Genetics & Biochemistry School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Orna Elroy-Stein
- Shmunis School of Biomedicine and Cancer Research, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Hagit Eldar-Finkelman
- The Department of Human Molecular Genetics & Biochemistry School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Sven Thoms
- Biochemistry and Molecular Medicine, Medical School EWL, Bielefeld University, Bielefeld, Germany
| | - Rina Rosin-Arbesfeld
- Department of Clinical Microbiology and Immunology, Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
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6
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Li S, Li J, Shi W, Nie Z, Zhang S, Ma F, Hu J, Chen J, Li P, Xie X. Pharmaceuticals Promoting Premature Termination Codon Readthrough: Progress in Development. Biomolecules 2023; 13:988. [PMID: 37371567 DOI: 10.3390/biom13060988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 05/27/2023] [Accepted: 06/06/2023] [Indexed: 06/29/2023] Open
Abstract
Around 11% of all known gene lesions causing human genetic diseases are nonsense mutations that introduce a premature stop codon (PTC) into the protein-coding gene sequence. Drug-induced PTC readthrough is a promising therapeutic strategy for treating hereditary diseases caused by nonsense mutations. To date, it has been found that more than 50 small-molecular compounds can promote PTC readthrough, known as translational readthrough-inducing drugs (TRIDs), and can be divided into two major categories: aminoglycosides and non-aminoglycosides. This review summarizes the pharmacodynamics and clinical application potential of the main TRIDs discovered so far, especially some newly discovered TRIDs in the past decade. The discovery of these TRIDs brings hope for treating nonsense mutations in various genetic diseases. Further research is still needed to deeply understand the mechanism of eukaryotic cell termination and drug-induced PTC readthrough so that patients can achieve the greatest benefit from the various TRID treatments.
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Affiliation(s)
- Shan Li
- School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China
| | - Juan Li
- Central Laboratory, The First Hospital of Lanzhou University, Lanzhou 730000, China
- Gansu Key Laboratory of Genetic Study of Hematopathy, The First Hospital of Lanzhou University, Lanzhou 730000, China
| | - Wenjing Shi
- School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China
| | - Ziyan Nie
- School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China
| | - Shasha Zhang
- School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China
| | - Fengdie Ma
- School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China
| | - Jun Hu
- School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China
| | - Jianjun Chen
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, China
| | - Peiqiang Li
- School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China
| | - Xiaodong Xie
- School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China
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7
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Valášek LS, Lukeš J, Paris Z. Stops making sense - For the people? Clin Transl Med 2023; 13:e1270. [PMID: 37203266 PMCID: PMC10196215 DOI: 10.1002/ctm2.1270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 05/09/2023] [Indexed: 05/20/2023] Open
Affiliation(s)
| | - Julius Lukeš
- Institute of ParasitologyBiology CentreCzech Academy of SciencesČeské Budějovice (Budweis)Czech Republic
- Faculty of SciencesUniversity of South BohemiaČeské Budějovice (Budweis)Czech Republic
| | - Zdeněk Paris
- Institute of ParasitologyBiology CentreCzech Academy of SciencesČeské Budějovice (Budweis)Czech Republic
- Faculty of SciencesUniversity of South BohemiaČeské Budějovice (Budweis)Czech Republic
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8
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Rubio A, Garland GD, Sfakianos A, Harvey RF, Willis AE. Aberrant protein synthesis and cancer development: The role of canonical eukaryotic initiation, elongation and termination factors in tumorigenesis. Semin Cancer Biol 2022; 86:151-165. [PMID: 35487398 DOI: 10.1016/j.semcancer.2022.04.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 04/11/2022] [Accepted: 04/20/2022] [Indexed: 01/27/2023]
Abstract
In tumourigenesis, oncogenes or dysregulated tumour suppressor genes alter the canonical translation machinery leading to a reprogramming of the translatome that, in turn, promotes the translation of selected mRNAs encoding proteins involved in proliferation and metastasis. It is therefore unsurprising that abnormal expression levels and activities of eukaryotic initiation factors (eIFs), elongation factors (eEFs) or termination factors (eRFs) are associated with poor outcome for patients with a wide range of cancers. In this review we discuss how RNA binding proteins (RBPs) within the canonical translation factor machinery are dysregulated in cancers and how targeting such proteins is leading to new therapeutic avenues.
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Affiliation(s)
- Angela Rubio
- MRC Toxicology Unit, University of Cambridge, Gleeson Building, Tennis Court Rd, Cambridge CB2 1QR, UK
| | - Gavin D Garland
- MRC Toxicology Unit, University of Cambridge, Gleeson Building, Tennis Court Rd, Cambridge CB2 1QR, UK
| | - Aristeidis Sfakianos
- MRC Toxicology Unit, University of Cambridge, Gleeson Building, Tennis Court Rd, Cambridge CB2 1QR, UK
| | - Robert F Harvey
- MRC Toxicology Unit, University of Cambridge, Gleeson Building, Tennis Court Rd, Cambridge CB2 1QR, UK
| | - Anne E Willis
- MRC Toxicology Unit, University of Cambridge, Gleeson Building, Tennis Court Rd, Cambridge CB2 1QR, UK.
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9
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Lee RE, Lewis CA, He L, Bulik-Sullivan EC, Gallant SC, Mascenik TM, Dang H, Cholon DM, Gentzsch M, Morton LC, Minges JT, Theile JW, Castle NA, Knowles MR, Kimple AJ, Randell SH. Small molecule eRF3a degraders rescue CFTR nonsense mutations by promoting premature termination codon readthrough. J Clin Invest 2022; 132:154571. [PMID: 35900863 PMCID: PMC9479597 DOI: 10.1172/jci154571] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 07/26/2022] [Indexed: 11/22/2022] Open
Abstract
The vast majority of people with cystic fibrosis (CF) are now eligible for CF transmembrane regulator (CFTR) modulator therapy. The remaining individuals with CF harbor premature termination codons (PTCs) or rare CFTR variants with limited treatment options. Although the clinical modulator response can be reliably predicted using primary airway epithelial cells, primary cells carrying rare CFTR variants are scarce. To overcome this obstacle, cell lines can be created by overexpression of mouse Bmi-1 and human TERT (hTERT). Using this approach, we developed 2 non-CF and 6 CF airway epithelial cell lines, 3 of which were homozygous for the W1282X PTC variant. The Bmi-1/hTERT cell lines recapitulated primary cell morphology and ion transport function. The 2 F508del-CFTR cell lines responded robustly to CFTR modulators, which was mirrored in the parent primary cells and in the cell donors’ clinical response. Cereblon E3 ligase modulators targeting eukaryotic release factor 3a (eRF3a) rescued W1282X-CFTR function to approximately 20% of WT levels and, when paired with G418, rescued G542X-CFTR function to approximately 50% of WT levels. Intriguingly, eRF3a degraders also diminished epithelial sodium channel (ENaC) function. These studies demonstrate that Bmi-1/hTERT cell lines faithfully mirrored primary cell responses to CFTR modulators and illustrate a therapeutic approach to rescue CFTR nonsense mutations.
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Affiliation(s)
- Rhianna E Lee
- Marsico Lung Institute/Cystic Fibrosis Research Center, University of North Carolina at Chapel Hill, Chapel Hill, United States of America
| | - Catherine A Lewis
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, United States of America
| | - Lihua He
- Marsico Lung Institute/Cystic Fibrosis Research Center, University of North Carolina at Chapel Hill, Chapel Hill, United States of America
| | - Emily C Bulik-Sullivan
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, United States of America
| | - Samuel C Gallant
- Marsico Lung Institute/Cystic Fibrosis Research Center, University of North Carolina at Chapel Hill, Chapel Hill, United States of America
| | - Teresa M Mascenik
- Marsico Lung Institute/Cystic Fibrosis Research Center, University of North Carolina at Chapel Hill, Chapel Hill, United States of America
| | - Hong Dang
- Marsico Lung Institute/Cystic Fibrosis Research Center, University of North Carolina at Chapel Hill, Chapel Hill, United States of America
| | - Deborah M Cholon
- Marsico Lung Institute/Cystic Fibrosis Research Center, University of North Carolina at Chapel Hill, Chapel Hill, United States of America
| | - Martina Gentzsch
- Department of Pediatrics, University of North Carolina at Chapel Hill, Chapel Hill, United States of America
| | - Lisa C Morton
- Marsico Lung Institute/Cystic Fibrosis Research Center, University of North Carolina at Chapel Hill, Chapel Hill, United States of America
| | - John T Minges
- Marsico Lung Institute/Cystic Fibrosis Research Center, University of North Carolina at Chapel Hill, Chapel Hill, United States of America
| | | | - Neil A Castle
- Research and Development, Icagen, Durham, United States of America
| | - Michael R Knowles
- Marsico Lung Institute/Cystic Fibrosis Research Center, University of North Carolina at Chapel Hill, Chapel Hill, United States of America
| | - Adam J Kimple
- Department of Otolaryngology, University of North Carolina at Chapel Hill, Chapel Hill, United States of America
| | - Scott H Randell
- Marsico Lung Institute/Cystic Fibrosis Research Center, University of North Carolina at Chapel Hill, Chapel Hill, United States of America
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10
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Sanderlin EJ, Keenan MM, Mense M, Revenko AS, Monia BP, Guo S, Huang L. CFTR mRNAs with nonsense codons are degraded by the SMG6-mediated endonucleolytic decay pathway. Nat Commun 2022; 13:2344. [PMID: 35487895 PMCID: PMC9054838 DOI: 10.1038/s41467-022-29935-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Accepted: 03/24/2022] [Indexed: 12/22/2022] Open
Abstract
Approximately 10% of cystic fibrosis patients harbor nonsense mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene which can generate nonsense codons in the CFTR mRNA and subsequently activate the nonsense-mediated decay (NMD) pathway resulting in rapid mRNA degradation. However, it is not known which NMD branches govern the decay of CFTR mRNAs containing nonsense codons. Here we utilize antisense oligonucleotides targeting NMD factors to evaluate the regulation of nonsense codon-containing CFTR mRNAs by the NMD pathway. We observe that CFTR mRNAs with nonsense codons G542X, R1162X, and W1282X, but not Y122X, require UPF2 and UPF3 for NMD. Furthermore, we demonstrate that all evaluated CFTR mRNAs harboring nonsense codons are degraded by the SMG6-mediated endonucleolytic pathway rather than the SMG5-SMG7-mediated exonucleolytic pathway. Finally, we show that upregulation of all evaluated CFTR mRNAs with nonsense codons by NMD pathway inhibition improves outcomes of translational readthrough therapy.
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Affiliation(s)
| | | | - Martin Mense
- Cystic Fibrosis Foundation Therapeutics Lab, Cystic Fibrosis Foundation, Lexington, MA, USA
| | | | | | - Shuling Guo
- Ionis Pharmaceuticals, Inc., Carlsbad, CA, USA
| | - Lulu Huang
- Ionis Pharmaceuticals, Inc., Carlsbad, CA, USA.
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11
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AAV-delivered suppressor tRNA overcomes a nonsense mutation in mice. Nature 2022; 604:343-348. [PMID: 35322228 PMCID: PMC9446716 DOI: 10.1038/s41586-022-04533-3] [Citation(s) in RCA: 45] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 01/05/2022] [Indexed: 12/19/2022]
Abstract
Gene therapy is a potentially curative medicine for many currently untreatable diseases, and recombinant adeno-associated virus (rAAV) is the most successful gene delivery vehicle for in vivo applications1-3. However, rAAV-based gene therapy suffers from several limitations, such as constrained DNA cargo size and toxicities caused by non-physiological expression of a transgene4-6. Here we show that rAAV delivery of a suppressor tRNA (rAAV.sup-tRNA) safely and efficiently rescued a genetic disease in a mouse model carrying a nonsense mutation, and effects lasted for more than 6 months after a single treatment. Mechanistically, this was achieved through a synergistic effect of premature stop codon readthrough and inhibition of nonsense-mediated mRNA decay. rAAV.sup-tRNA had a limited effect on global readthrough at normal stop codons and did not perturb endogenous tRNA homeostasis, as determined by ribosome profiling and tRNA sequencing, respectively. By optimizing the AAV capsid and the route of administration, therapeutic efficacy in various target tissues was achieved, including liver, heart, skeletal muscle and brain. This study demonstrates the feasibility of developing a toolbox of AAV-delivered nonsense suppressor tRNAs operating on premature termination codons (AAV-NoSTOP) to rescue pathogenic nonsense mutations and restore gene function under endogenous regulation. As nonsense mutations account for 11% of pathogenic mutations, AAV-NoSTOP can benefit a large number of patients. AAV-NoSTOP obviates the need to deliver a full-length protein-coding gene that may exceed the rAAV packaging limit, elicit adverse immune responses or cause transgene-related toxicities. It therefore represents a valuable addition to gene therapeutics.
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12
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Gene Amplification as a Mechanism of Yeast Adaptation to Nonsense Mutations in Release Factor Genes. Genes (Basel) 2021; 12:genes12122019. [PMID: 34946968 PMCID: PMC8701342 DOI: 10.3390/genes12122019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 12/13/2021] [Accepted: 12/15/2021] [Indexed: 11/17/2022] Open
Abstract
Protein synthesis (translation) is one of the fundamental processes occurring in the cells of living organisms. Translation can be divided into three key steps: initiation, elongation, and termination. In the yeast Saccharomyces cerevisiae, there are two translation termination factors, eRF1 and eRF3. These factors are encoded by the SUP45 and SUP35 genes, which are essential; deletion of any of them leads to the death of yeast cells. However, viable strains with nonsense mutations in both the SUP35 and SUP45 genes were previously obtained in several groups. The survival of such mutants clearly involves feedback control of premature stop codon readthrough; however, the exact molecular basis of such feedback control remain unclear. To investigate the genetic factors supporting the viability of these SUP35 and SUP45 nonsense mutants, we performed whole-genome sequencing of strains carrying mutant sup35-n and sup45-n alleles; while no common SNPs or indels were found in these genomes, we discovered a systematic increase in the copy number of the plasmids carrying mutant sup35-n and sup45-n alleles. We used the qPCR method which confirmed the differences in the relative number of SUP35 and SUP45 gene copies between strains carrying wild-type or mutant alleles of SUP35 and SUP45 genes. Moreover, we compare the number of copies of the SUP35 and SUP45 genes in strains carrying different nonsense mutant variants of these genes as a single chromosomal copy. qPCR results indicate that the number of mutant gene copies is increased compared to the wild-type control. In case of several sup45-n alleles, this was due to a disomy of the entire chromosome II, while for the sup35-218 mutation we observed a local duplication of a segment of chromosome IV containing the SUP35 gene. Taken together, our results indicate that gene amplification is a common mechanism of adaptation to nonsense mutations in release factor genes in yeast.
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13
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Sharma J, Du M, Wong E, Mutyam V, Li Y, Chen J, Wangen J, Thrasher K, Fu L, Peng N, Tang L, Liu K, Mathew B, Bostwick RJ, Augelli-Szafran CE, Bihler H, Liang F, Mahiou J, Saltz J, Rab A, Hong J, Sorscher EJ, Mendenhall EM, Coppola CJ, Keeling KM, Green R, Mense M, Suto MJ, Rowe SM, Bedwell DM. A small molecule that induces translational readthrough of CFTR nonsense mutations by eRF1 depletion. Nat Commun 2021; 12:4358. [PMID: 34272367 PMCID: PMC8285393 DOI: 10.1038/s41467-021-24575-x] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 06/22/2021] [Indexed: 11/09/2022] Open
Abstract
Premature termination codons (PTCs) prevent translation of a full-length protein and trigger nonsense-mediated mRNA decay (NMD). Nonsense suppression (also termed readthrough) therapy restores protein function by selectively suppressing translation termination at PTCs. Poor efficacy of current readthrough agents prompted us to search for better compounds. An NMD-sensitive NanoLuc readthrough reporter was used to screen 771,345 compounds. Among the 180 compounds identified with readthrough activity, SRI-37240 and its more potent derivative SRI-41315, induce a prolonged pause at stop codons and suppress PTCs associated with cystic fibrosis in immortalized and primary human bronchial epithelial cells, restoring CFTR expression and function. SRI-41315 suppresses PTCs by reducing the abundance of the termination factor eRF1. SRI-41315 also potentiates aminoglycoside-mediated readthrough, leading to synergistic increases in CFTR activity. Combining readthrough agents that target distinct components of the translation machinery is a promising treatment strategy for diseases caused by PTCs. Premature termination codons can cause early translation termination and lead to disease. Here the authors perform a screen to identify compounds with readthrough activity and show that these reduce eRF1 levels to suppress premature termination associated with cystic fibrosis.
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Affiliation(s)
- Jyoti Sharma
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham (UAB), Birmingham, AL, USA.,Department of Medicine, University of Alabama at Birmingham (UAB), Birmingham, AL, USA.,Department of Microbiology, University of Alabama at Birmingham (UAB), Birmingham, AL, USA
| | - Ming Du
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham (UAB), Birmingham, AL, USA.,Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham (UAB), Birmingham, AL, USA
| | - Eric Wong
- CFFT Lab, Cystic Fibrosis Foundation, Lexington, MA, USA
| | - Venkateshwar Mutyam
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham (UAB), Birmingham, AL, USA.,Department of Medicine, University of Alabama at Birmingham (UAB), Birmingham, AL, USA
| | - Yao Li
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham (UAB), Birmingham, AL, USA.,Department of Medicine, University of Alabama at Birmingham (UAB), Birmingham, AL, USA
| | - Jianguo Chen
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham (UAB), Birmingham, AL, USA.,Department of Medicine, University of Alabama at Birmingham (UAB), Birmingham, AL, USA
| | - Jamie Wangen
- Department of Molecular Biology and Genetics and Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Kari Thrasher
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham (UAB), Birmingham, AL, USA.,Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham (UAB), Birmingham, AL, USA
| | - Lianwu Fu
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham (UAB), Birmingham, AL, USA.,Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham (UAB), Birmingham, AL, USA
| | - Ning Peng
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham (UAB), Birmingham, AL, USA.,Department of Medicine, University of Alabama at Birmingham (UAB), Birmingham, AL, USA
| | - Liping Tang
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham (UAB), Birmingham, AL, USA.,Department of Medicine, University of Alabama at Birmingham (UAB), Birmingham, AL, USA
| | - Kaimao Liu
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham (UAB), Birmingham, AL, USA.,Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham (UAB), Birmingham, AL, USA
| | | | | | | | - Hermann Bihler
- CFFT Lab, Cystic Fibrosis Foundation, Lexington, MA, USA
| | - Feng Liang
- CFFT Lab, Cystic Fibrosis Foundation, Lexington, MA, USA
| | - Jerome Mahiou
- CFFT Lab, Cystic Fibrosis Foundation, Lexington, MA, USA
| | - Josef Saltz
- CFFT Lab, Cystic Fibrosis Foundation, Lexington, MA, USA
| | - Andras Rab
- Department of Pediatrics, Emory University, Atlanta, Georgia
| | - Jeong Hong
- Department of Pediatrics, Emory University, Atlanta, Georgia
| | - Eric J Sorscher
- Department of Pediatrics, Emory University, Atlanta, Georgia
| | - Eric M Mendenhall
- Department of Biological Sciences, The University of Alabama in Huntsville, Huntsville, AL, USA
| | - Candice J Coppola
- Department of Biological Sciences, The University of Alabama in Huntsville, Huntsville, AL, USA
| | - Kim M Keeling
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham (UAB), Birmingham, AL, USA.,Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham (UAB), Birmingham, AL, USA
| | - Rachel Green
- Department of Molecular Biology and Genetics and Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Martin Mense
- CFFT Lab, Cystic Fibrosis Foundation, Lexington, MA, USA
| | | | - Steven M Rowe
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham (UAB), Birmingham, AL, USA.,Department of Medicine, University of Alabama at Birmingham (UAB), Birmingham, AL, USA.,Department of Pediatrics, University of Alabama at Birmingham (UAB), Birmingham, AL, USA
| | - David M Bedwell
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham (UAB), Birmingham, AL, USA. .,Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham (UAB), Birmingham, AL, USA.
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14
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Porter JJ, Heil CS, Lueck JD. Therapeutic promise of engineered nonsense suppressor tRNAs. WILEY INTERDISCIPLINARY REVIEWS. RNA 2021; 12:e1641. [PMID: 33567469 PMCID: PMC8244042 DOI: 10.1002/wrna.1641] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Revised: 12/16/2020] [Accepted: 12/23/2020] [Indexed: 12/11/2022]
Abstract
Nonsense mutations change an amino acid codon to a premature termination codon (PTC) generally through a single-nucleotide substitution. The generation of a PTC results in a defective truncated protein and often in severe forms of disease. Because of the exceedingly high prevalence of nonsense-associated diseases and a unifying mechanism, there has been a concerted effort to identify PTC therapeutics. Most clinical trials for PTC therapeutics have been conducted with small molecules that promote PTC read through and incorporation of a near-cognate amino acid. However, there is a need for PTC suppression agents that recode PTCs with the correct amino acid while being applicable to PTC mutations in many different genomic landscapes. With these characteristics, a single therapeutic will be able to treat several disease-causing PTCs. In this review, we will focus on the use of nonsense suppression technologies, in particular, suppressor tRNAs (sup-tRNAs), as possible therapeutics for correcting PTCs. Sup-tRNAs have many attractive qualities as possible therapeutic agents although there are knowledge gaps on their function in mammalian cells and technical hurdles that need to be overcome before their promise is realized. This article is categorized under: RNA Processing > tRNA Processing Translation > Translation Regulation.
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Affiliation(s)
- Joseph J. Porter
- Department of Pharmacology and PhysiologyUniversity of Rochester Medical CenterRochesterNew YorkUSA
| | - Christina S. Heil
- Department of Pharmacology and PhysiologyUniversity of Rochester Medical CenterRochesterNew YorkUSA
| | - John D. Lueck
- Department of Pharmacology and PhysiologyUniversity of Rochester Medical CenterRochesterNew YorkUSA
- Department of NeurologyUniversity of Rochester Medical CenterRochesterNew YorkUSA
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15
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Baradaran-Heravi A, Balgi AD, Hosseini-Farahabadi S, Choi K, Has C, Roberge M. Effect of small molecule eRF3 degraders on premature termination codon readthrough. Nucleic Acids Res 2021; 49:3692-3708. [PMID: 33764477 PMCID: PMC8053119 DOI: 10.1093/nar/gkab194] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 03/04/2021] [Accepted: 03/10/2021] [Indexed: 12/16/2022] Open
Abstract
Premature termination codon (PTC) readthrough is considered a potential treatment for genetic diseases caused by nonsense mutations. High concentrations of aminoglycosides induce low levels of PTC readthrough but also elicit severe toxicity. Identifying compounds that enhance PTC readthrough by aminoglycosides or reduce their toxicity is a continuing challenge. In humans, a binary complex of eukaryotic release factors 1 (eRF1) and 3 (eRF3a or eRF3b) mediates translation termination. They also participate in the SURF (SMG1-UPF1-eRF1-eRF3) complex assembly involved in nonsense-mediated mRNA decay (NMD). We show that PTC readthrough by aminoglycoside G418 is considerably enhanced by eRF3a and eRF3b siRNAs and cereblon E3 ligase modulators CC-885 and CC-90009, which induce proteasomal degradation of eRF3a and eRF3b. eRF3 degradation also reduces eRF1 levels and upregulates UPF1 and selectively stabilizes TP53 transcripts bearing a nonsense mutation over WT, indicating NMD suppression. CC-90009 is considerably less toxic than CC-885 and it enhances PTC readthrough in combination with aminoglycosides in mucopolysaccharidosis type I-Hurler, late infantile neuronal ceroid lipofuscinosis, Duchenne muscular dystrophy and junctional epidermolysis bullosa patient-derived cells with nonsense mutations in the IDUA, TPP1, DMD and COL17A1 genes, respectively. Combination of CC-90009 with aminoglycosides such as gentamicin or ELX-02 may have potential for PTC readthrough therapy.
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Affiliation(s)
- Alireza Baradaran-Heravi
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Aruna D Balgi
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Sara Hosseini-Farahabadi
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Kunho Choi
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Cristina Has
- Department of Dermatology, Medical Center-University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | - Michel Roberge
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
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16
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Mangano K, Florin T, Shao X, Klepacki D, Chelysheva I, Ignatova Z, Gao Y, Mankin AS, Vázquez-Laslop N. Genome-wide effects of the antimicrobial peptide apidaecin on translation termination in bacteria. eLife 2020; 9:e62655. [PMID: 33031031 PMCID: PMC7544508 DOI: 10.7554/elife.62655] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 09/20/2020] [Indexed: 12/16/2022] Open
Abstract
Biochemical studies suggested that the antimicrobial peptide apidaecin (Api) inhibits protein synthesis by binding in the nascent peptide exit tunnel and trapping the release factor associated with a terminating ribosome. The mode of Api action in bacterial cells had remained unknown. Here genome-wide analysis reveals that in bacteria, Api arrests translating ribosomes at stop codons and causes pronounced queuing of the trailing ribosomes. By sequestering the available release factors, Api promotes pervasive stop codon bypass, leading to the expression of proteins with C-terminal extensions. Api-mediated translation arrest leads to the futile activation of the ribosome rescue systems. Understanding the unique mechanism of Api action in living cells may facilitate the development of new medicines and research tools for genome exploration.
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Affiliation(s)
- Kyle Mangano
- Center for Biomolecular Sciences, University of Illinois at ChicagoChicagoUnited States
- Department of Pharmaceutical Sciences, University of Illinois at ChicagoChicagoUnited States
| | - Tanja Florin
- Center for Biomolecular Sciences, University of Illinois at ChicagoChicagoUnited States
| | - Xinhao Shao
- Department of Pharmaceutical Sciences, University of Illinois at ChicagoChicagoUnited States
| | - Dorota Klepacki
- Center for Biomolecular Sciences, University of Illinois at ChicagoChicagoUnited States
| | - Irina Chelysheva
- Institute of Biochemistry and Molecular Biology, University of HamburgHamburgGermany
| | - Zoya Ignatova
- Institute of Biochemistry and Molecular Biology, University of HamburgHamburgGermany
| | - Yu Gao
- Department of Pharmaceutical Sciences, University of Illinois at ChicagoChicagoUnited States
| | - Alexander S Mankin
- Center for Biomolecular Sciences, University of Illinois at ChicagoChicagoUnited States
- Department of Pharmaceutical Sciences, University of Illinois at ChicagoChicagoUnited States
| | - Nora Vázquez-Laslop
- Center for Biomolecular Sciences, University of Illinois at ChicagoChicagoUnited States
- Department of Pharmaceutical Sciences, University of Illinois at ChicagoChicagoUnited States
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Morais P, Adachi H, Yu YT. Suppression of Nonsense Mutations by New Emerging Technologies. Int J Mol Sci 2020; 21:ijms21124394. [PMID: 32575694 PMCID: PMC7352488 DOI: 10.3390/ijms21124394] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 06/17/2020] [Accepted: 06/18/2020] [Indexed: 12/18/2022] Open
Abstract
Nonsense mutations often result from single nucleotide substitutions that change a sense codon (coding for an amino acid) to a nonsense or premature termination codon (PTC) within the coding region of a gene. The impact of nonsense mutations is two-fold: (1) the PTC-containing mRNA is degraded by a surveillance pathway called nonsense-mediated mRNA decay (NMD) and (2) protein translation stops prematurely at the PTC codon, and thus no functional full-length protein is produced. As such, nonsense mutations result in a large number of human diseases. Nonsense suppression is a strategy that aims to correct the defects of hundreds of genetic disorders and reverse disease phenotypes and conditions. While most clinical trials have been performed with small molecules, there is an increasing need for sequence-specific repair approaches that are safer and adaptable to personalized medicine. Here, we discuss recent advances in both conventional strategies as well as new technologies. Several of these will soon be tested in clinical trials as nonsense therapies, even if they still have some limitations and challenges to overcome.
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Affiliation(s)
- Pedro Morais
- ProQR Therapeutics, Zernikedreef 9, 2333 CK Leiden, The Netherlands;
| | - Hironori Adachi
- Department of Biochemistry and Biophysics, Center for RNA Biology, University of Rochester Medical Center, 601 Elmwood Avenue, Rochester, NY 14642, USA;
| | - Yi-Tao Yu
- Department of Biochemistry and Biophysics, Center for RNA Biology, University of Rochester Medical Center, 601 Elmwood Avenue, Rochester, NY 14642, USA;
- Correspondence: ; Tel.: +1-(585)-275-1271; Fax: +1-(585)-275-6007
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18
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Kaniowski D, Kulik K, Ebenryter-Olbińska K, Wielgus E, Lesnikowski Z, Nawrot B. Metallacarborane Complex Boosts the Rate of DNA Oligonucleotide Hydrolysis in the Reaction Catalyzed by Snake Venom Phosphodiesterase. Biomolecules 2020; 10:biom10050718. [PMID: 32380792 PMCID: PMC7277537 DOI: 10.3390/biom10050718] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 04/30/2020] [Accepted: 05/04/2020] [Indexed: 12/17/2022] Open
Abstract
Antisense oligonucleotides conjugated with boron clusters (B-ASOs) have been described as potential gene expression inhibitors and carriers of boron for boron neutron capture therapy (BNCT), providing a dual-action therapeutic platform. In this study, we tested the nucleolytic stability of DNA oligonucleotides labeled with metallacarborane [(3,3'-iron-1,2,1',2'-dicarbollide)(-1)]ate [Fe(C2B9H11)2] (FESAN) against snake venom phosphodiesterase (svPDE, 3'→5'-exonuclease). Contrary to the previously observed protective effect of carborane (C2B10H12) modifications, the B-ASOs containing a metallacarborane moiety at the 5'-end of the oligonucleotide chain were hydrolyzed faster than their parent nonmodified oligomers. Interestingly, an enhancement in the hydrolysis rate was also observed in the presence of free metallacarborane, and this reaction was dependent on the concentration of the metallacarborane. Microscale thermophoresis (MST) analysis confirmed the high affinity (Kd nM range) of the binding of the metallacarborane to the proteins of crude snake venom and the moderate affinity (Kd µM range) between the metallacarborane and the short single-stranded DNA. We hypothesize that the metallacarborane complex covalently bound to B-ASO holds DNA molecules close to the protein surface, facilitating enzymatic cleavage. The addition of metallacarborane alone to the ASO/svPDE reaction mixture provides the interface to attract freely floating DNA molecules. In both cases, the local DNA concentration around the enzymes increases, giving rise to faster hydrolysis. It was experimentally shown that an allosteric effect, possibly attributable to the observed boost in the 3´→5´-exonucleolytic activity of snake venom phosphodiesterase, is much less plausible.
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Affiliation(s)
- Damian Kaniowski
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland; (D.K.); (K.K.); (K.E.-O.); (E.W.)
| | - Katarzyna Kulik
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland; (D.K.); (K.K.); (K.E.-O.); (E.W.)
| | - Katarzyna Ebenryter-Olbińska
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland; (D.K.); (K.K.); (K.E.-O.); (E.W.)
| | - Ewelina Wielgus
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland; (D.K.); (K.K.); (K.E.-O.); (E.W.)
| | - Zbigniew Lesnikowski
- Institute of Medical Biology, Polish Academy of Sciences, Laboratory of Medicinal Chemistry, 106 Lodowa St., 92-232 Lodz, Poland;
| | - Barbara Nawrot
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland; (D.K.); (K.K.); (K.E.-O.); (E.W.)
- Correspondence: ; Tel.: +48-42-6803248
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Christopher Boyd A, Guo S, Huang L, Kerem B, Oren YS, Walker AJ, Hart SL. New approaches to genetic therapies for cystic fibrosis. J Cyst Fibros 2020; 19 Suppl 1:S54-S59. [PMID: 31948871 DOI: 10.1016/j.jcf.2019.12.012] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 12/20/2019] [Accepted: 12/22/2019] [Indexed: 12/19/2022]
Abstract
Gene therapy offers great promise for cystic fibrosis which has never been quite fulfilled due to the challenges of delivering sufficient amounts of the CFTR gene and expression persistence for a sufficient period of time in the lungs to have any effect. Initial trials explored both viral and non-viral vectors but failed to achieve a significant breakthrough. However, in recent years, new opportunities have emerged that exploit our increased knowledge and understanding of the biology of CF and the airway epithelium. New technologies include new viral and non-viral vector approaches to delivery, but also alternative nucleic acid technologies including oligonucleotides and siRNA approaches for gene silencing and gene splicing, described in this review, as presented at the 2019 annual European CF Society Basic Science meeting (Dubrovnik, Croatia). We also briefly discuss other emerging technologies including mRNA and CRISPR gene editing that are advancing rapidly. The future prospects for genetic therapies for CF are now diverse and more promising probably than any time since the discovery of the CF gene.
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Affiliation(s)
- A Christopher Boyd
- University of Edinburgh, Centre for Genomic and Experimental Medicine, University of Edinburgh and Institute of Genetics & Molecular Medicine, Western General Hospital, Edinburgh UK; UK Cystic Fibrosis Gene Therapy Consortium, UK
| | - Shuling Guo
- Antisense Drug Discovery, Ionis Pharmaceuticals, Carlsbad, California, USA
| | - Lulu Huang
- Antisense Drug Discovery, Ionis Pharmaceuticals, Carlsbad, California, USA
| | - Batsheva Kerem
- Department of Genetics, The Life Sciences Institute, The Hebrew University of Jerusalem, Jerusalem Israel; SpliSenseTherapeutics, Givat Ram Campus, Hebrew University, Jerusalem, Israel
| | - Yifat S Oren
- SpliSenseTherapeutics, Givat Ram Campus, Hebrew University, Jerusalem, Israel
| | - Amy J Walker
- Department of Genetics and Genomic Medicine, UCL Great Ormond Street Institute of Child Health, London UK
| | - Stephen L Hart
- Department of Genetics and Genomic Medicine, UCL Great Ormond Street Institute of Child Health, London UK.
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