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Malard F, Wolter AC, Marquevielle J, Morvan E, Ecoutin A, Rüdisser S, Allain FT, Campagne S. The diversity of splicing modifiers acting on A-1 bulged 5'-splice sites reveals rules for rational drug design. Nucleic Acids Res 2024; 52:4124-4136. [PMID: 38554107 PMCID: PMC11077090 DOI: 10.1093/nar/gkae201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 12/07/2023] [Accepted: 03/07/2024] [Indexed: 04/01/2024] Open
Abstract
Pharmacological modulation of RNA splicing by small molecules is an emerging facet of drug discovery. In this context, the SMN2 splicing modifier SMN-C5 was used as a prototype to understand the mode of action of small molecule splicing modifiers and propose the concept of 5'-splice site bulge repair. In this study, we combined in vitro binding assays and structure determination by NMR spectroscopy to identify the binding modes of four other small molecule splicing modifiers that switch the splicing of either the SMN2 or the HTT gene. Here, we determined the solution structures of risdiplam, branaplam, SMN-CX and SMN-CY bound to the intermolecular RNA helix epitope containing an unpaired adenine within the G-2A-1G+1U+2 motif of the 5'-splice site. Despite notable differences in their scaffolds, risdiplam, SMN-CX, SMN-CY and branaplam contact the RNA epitope similarly to SMN-C5, suggesting that the 5'-splice site bulge repair mechanism can be generalised. These findings not only deepen our understanding of the chemical diversity of splicing modifiers that target A-1 bulged 5'-splice sites, but also identify common pharmacophores required for modulating 5'-splice site selection with small molecules.
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Affiliation(s)
- Florian Malard
- Université de Bordeaux, Inserm U1212, CNRS UMR5320, ARNA unit, 146 rue Léo Saignat, 33076 Bordeaux Cedex, France
- Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, 33607 Pessac Cedex, France
| | - Antje C Wolter
- ETH Zürich, Department of Biology, Institute of Biochemistry, Hönggerbergring 64, 8093 Zürich, Switzerland
| | - Julien Marquevielle
- Université de Bordeaux, Inserm U1212, CNRS UMR5320, ARNA unit, 146 rue Léo Saignat, 33076 Bordeaux Cedex, France
- Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, 33607 Pessac Cedex, France
| | - Estelle Morvan
- Institut Européen de Chimie et Biologie, UAR3033 CNRS, Université de Bordeaux, INSERM US01, Pessac 33600, France
| | - Agathe Ecoutin
- Université de Bordeaux, Inserm U1212, CNRS UMR5320, ARNA unit, 146 rue Léo Saignat, 33076 Bordeaux Cedex, France
- Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, 33607 Pessac Cedex, France
| | - Simon H Rüdisser
- ETH Zürich, Department of Biology, BioNMR platform, Hönggerbergring 64, 8093 Zürich, Switzerland
| | - Frédéric H T Allain
- ETH Zürich, Department of Biology, Institute of Biochemistry, Hönggerbergring 64, 8093 Zürich, Switzerland
| | - Sebastien Campagne
- Université de Bordeaux, Inserm U1212, CNRS UMR5320, ARNA unit, 146 rue Léo Saignat, 33076 Bordeaux Cedex, France
- Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, 33607 Pessac Cedex, France
- ETH Zürich, Department of Biology, Institute of Biochemistry, Hönggerbergring 64, 8093 Zürich, Switzerland
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2
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Gadek M, Sherr EH, Floor SN. The variant landscape and function of DDX3X in cancer and neurodevelopmental disorders. Trends Mol Med 2023; 29:726-739. [PMID: 37422363 DOI: 10.1016/j.molmed.2023.06.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 06/12/2023] [Accepted: 06/14/2023] [Indexed: 07/10/2023]
Abstract
RNA molecules rely on proteins across their life cycle. DDX3X encodes an X-linked DEAD-box RNA helicase with a Y-linked paralog, DDX3Y. DDX3X is central to the RNA life cycle and is implicated in many conditions, including cancer and the neurodevelopmental disorder DDX3X syndrome. DDX3X-linked conditions often exhibit sex differences, possibly due to differences between expression or function of the X- and Y-linked paralogs DDX3X and DDX3Y. DDX3X-related diseases have different mutational landscapes, indicating different roles of DDX3X. Understanding the role of DDX3X in normal and disease states will inform the understanding of DDX3X in disease. We review the function of DDX3X and DDX3Y, discuss how mutation type and sex bias contribute to human diseases involving DDX3X, and review possible DDX3X-targeting treatments.
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Affiliation(s)
- Margaret Gadek
- Department of Cell and Tissue Biology, University of California, San Francisco, CA 94143, USA
| | - Elliott H Sherr
- Department of Neurology, University of California, San Francisco, CA 94143, USA
| | - Stephen N Floor
- Department of Cell and Tissue Biology, University of California, San Francisco, CA 94143, USA; Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, CA 94143, USA.
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3
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Genna V, Iglesias-Fernández J, Reyes-Fraile L, Villegas N, Guckian K, Seth P, Wan B, Cabrero C, Terrazas M, Brun-Heath I, González C, Sciabola S, Villalobos A, Orozco M. Controlled sulfur-based engineering confers mouldability to phosphorothioate antisense oligonucleotides. Nucleic Acids Res 2023; 51:4713-4725. [PMID: 37099382 PMCID: PMC10250214 DOI: 10.1093/nar/gkad309] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 04/04/2023] [Accepted: 04/24/2023] [Indexed: 04/27/2023] Open
Abstract
Phosphorothioates (PS) have proven their effectiveness in the area of therapeutic oligonucleotides with applications spanning from cancer treatment to neurodegenerative disorders. Initially, PS substitution was introduced for the antisense oligonucleotides (PS ASOs) because it confers an increased nuclease resistance meanwhile ameliorates cellular uptake and in-vivo bioavailability. Thus, PS oligonucleotides have been elevated to a fundamental asset in the realm of gene silencing therapeutic methodologies. But, despite their wide use, little is known on the possibly different structural changes PS-substitutions may provoke in DNA·RNA hybrids. Additionally, scarce information and significant controversy exists on the role of phosphorothioate chirality in modulating PS properties. Here, through comprehensive computational investigations and experimental measurements, we shed light on the impact of PS chirality in DNA-based antisense oligonucleotides; how the different phosphorothioate diastereomers impact DNA topology, stability and flexibility to ultimately disclose pro-Sp S and pro-Rp S roles at the catalytic core of DNA Exonuclease and Human Ribonuclease H; two major obstacles in ASOs-based therapies. Altogether, our results provide full-atom and mechanistic insights on the structural aberrations PS-substitutions provoke and explain the origin of nuclease resistance PS-linkages confer to DNA·RNA hybrids; crucial information to improve current ASOs-based therapies.
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Affiliation(s)
- Vito Genna
- Mechanisms of Diseases, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, Barcelona 08028, Spain
- NBD | Nostrum Biodiscovery, Baldiri Reixac 10, Barcelona 08028, Spain
| | | | - Laura Reyes-Fraile
- Mechanisms of Diseases, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, Barcelona 08028, Spain
| | - Nuria Villegas
- Mechanisms of Diseases, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, Barcelona 08028, Spain
| | | | - Punit Seth
- Ionis Pharmaceuticals Inc., 2855 Gazelle Court, Carlsbad, CA 92010, USA
| | - Brad Wan
- Ionis Pharmaceuticals Inc., 2855 Gazelle Court, Carlsbad, CA 92010, USA
| | - Cristina Cabrero
- Instituto de Química Física Rocasolano, C/ Serrano 119, Madrid 28006, Spain
| | - Montserrat Terrazas
- Mechanisms of Diseases, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, Barcelona 08028, Spain
- Department of Inorganic and Organic Chemistry, Section of Organic Chemistry, IBUB, University of Barcelona, Martí i Franquès 1-11, 08028 Barcelona, Spain
| | - Isabelle Brun-Heath
- Mechanisms of Diseases, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, Barcelona 08028, Spain
| | - Carlos González
- Instituto de Química Física Rocasolano, C/ Serrano 119, Madrid 28006, Spain
| | | | | | - Modesto Orozco
- Mechanisms of Diseases, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, Barcelona 08028, Spain
- Department of Biochemistry and Biomedicine, University of Barcelona, Barcelona 08028, Spain
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4
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Kerschner JL, Paranjapye A, Harris A. Cellular heterogeneity in the 16HBE14o - airway epithelial line impacts biological readouts. Physiol Rep 2023; 11:e15700. [PMID: 37269165 PMCID: PMC10238858 DOI: 10.14814/phy2.15700] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 04/15/2023] [Accepted: 04/16/2023] [Indexed: 06/04/2023] Open
Abstract
The airway epithelial cell line, 16HBE14o- , is an important cell model for studying airway disease. 16HBE14o- cells were originally generated from primary human bronchial epithelial cells by SV40-mediated immortalization, a process that is associated with genomic instability through long-term culture. Here, we explore the heterogeneity of these cells, with respect to expression of the cystic fibrosis transmembrane conductance regulator (CFTR) transcript and protein. We isolate clones of 16HBE14o- with stably higher and lower levels of CFTR in comparison to bulk 16HBE14o- , designated CFTRhigh and CFTRlow . Detailed characterization of the CFTR locus in these clones by ATAC-seq and 4C-seq showed open chromatin profiles and higher order chromatin structure that correlate with CFTR expression levels. Transcriptomic profiling of CFTRhigh and CFTRlow cells showed that the CFTRhigh cells had an elevated inflammatory/innate immune response phenotype. These results encourage caution in interpreting functional data from clonal lines of 16HBE14o- cells, generated after genomic or other manipulations.
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Affiliation(s)
- Jenny L. Kerschner
- Department of Genetics and Genome SciencesCase Western Reserve UniversityClevelandOhioUSA
| | - Alekh Paranjapye
- Department of Genetics and Genome SciencesCase Western Reserve UniversityClevelandOhioUSA
- Present address:
Department of GeneticsUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
| | - Ann Harris
- Department of Genetics and Genome SciencesCase Western Reserve UniversityClevelandOhioUSA
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5
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Leroy C, Spelier S, Essonghe NC, Poix V, Kong R, Gizzi P, Bourban C, Amand S, Bailly C, Guilbert R, Hannebique D, Persoons P, Arhant G, Prévotat A, Reix P, Hubert D, Gérardin M, Chamaillard M, Prevarskaya N, Rebuffat S, Shapovalov G, Beekman J, Lejeune F. Use of 2,6-diaminopurine as a potent suppressor of UGA premature stop codons in cystic fibrosis. Mol Ther 2023; 31:970-985. [PMID: 36641622 PMCID: PMC10124085 DOI: 10.1016/j.ymthe.2023.01.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 12/10/2022] [Accepted: 01/12/2023] [Indexed: 01/16/2023] Open
Abstract
Nonsense mutations are responsible for around 10% of cases of genetic diseases, including cystic fibrosis. 2,6-diaminopurine (DAP) has recently been shown to promote efficient readthrough of UGA premature stop codons. In this study, we show that DAP can correct a nonsense mutation in the Cftr gene in vivo in a new CF mouse model, in utero, and through breastfeeding, thanks, notably, to adequate pharmacokinetic properties. DAP turns out to be very stable in plasma and is distributed throughout the body. The ability of DAP to correct various endogenous UGA nonsense mutations in the CFTR gene and to restore its function in mice, in organoids derived from murine or patient cells, and in cells from patients with cystic fibrosis reveals the potential of such readthrough-stimulating molecules in developing a therapeutic approach. The fact that correction by DAP of certain nonsense mutations reaches a clinically relevant level, as judged from previous studies, makes the use of this compound all the more attractive.
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Affiliation(s)
- Catherine Leroy
- University Lille, CNRS, INSERM, UMR9020-U1277-CANTHER-Cancer Heterogeneity Plasticity and Resistance to Therapies, 59000 Lille, France; Unité Tumorigenèse et Résistance aux Traitements, Institut Pasteur de Lille, 59000 Lille, France
| | - Sacha Spelier
- Pediatric Respiratory Medicine, Wilhelmina Children's Hospital, University Medical Center, Utrecht University, 3584 EA Utrecht, the Netherlands; Regenerative Medicine Utrecht, University Medical Center, Utrecht University, 3584 CT Utrecht, the Netherlands; Center for Living Technologies, University Medical Center, Utrecht University, 3584 CT Utrecht, the Netherlands
| | - Nadège Charlene Essonghe
- University Lille, INSERM, U1003-PHYCEL-Physiologie Cellulaire, 59000 Lille, France; Laboratory of Excellence, Ion Channels Science and Therapeutics, 59655 Villeneuve d'Ascq, France
| | - Virginie Poix
- University Lille, CNRS, INSERM, UMR9020-U1277-CANTHER-Cancer Heterogeneity Plasticity and Resistance to Therapies, 59000 Lille, France; Unité Tumorigenèse et Résistance aux Traitements, Institut Pasteur de Lille, 59000 Lille, France
| | - Rebekah Kong
- University Lille, CNRS, INSERM, UMR9020-U1277-CANTHER-Cancer Heterogeneity Plasticity and Resistance to Therapies, 59000 Lille, France; Unité Tumorigenèse et Résistance aux Traitements, Institut Pasteur de Lille, 59000 Lille, France
| | - Patrick Gizzi
- Plateforme de Chimie Biologique Intégrative de Strasbourg, UAR 3286 CNRS-Université de Strasbourg, 67404 Illkirch, France
| | - Claire Bourban
- Plateforme de Chimie Biologique Intégrative de Strasbourg, UAR 3286 CNRS-Université de Strasbourg, 67404 Illkirch, France
| | - Séverine Amand
- Muséum National d'Histoire Naturelle, Centre National de la Recherche Scientifique, Laboratory of Molecules of Communication and Adaptation of Microorganisms (MCAM), UMR 7245 CNRS-MNHN, CP 54, 57 Rue Cuvier, 75005 Paris, France
| | - Christine Bailly
- Muséum National d'Histoire Naturelle, Centre National de la Recherche Scientifique, Laboratory of Molecules of Communication and Adaptation of Microorganisms (MCAM), UMR 7245 CNRS-MNHN, CP 54, 57 Rue Cuvier, 75005 Paris, France
| | - Romain Guilbert
- Institut Pasteur de Lille-PLEHTA (Plateforme d'Expérimentation et de Haute Technologie Animale), 59019 Lille, France
| | - David Hannebique
- Institut Pasteur de Lille-PLEHTA (Plateforme d'Expérimentation et de Haute Technologie Animale), 59019 Lille, France
| | - Philippe Persoons
- Institut Pasteur de Lille-PLEHTA (Plateforme d'Expérimentation et de Haute Technologie Animale), 59019 Lille, France
| | - Gwenaëlle Arhant
- University Lille, CNRS, INSERM, UMR9020-U1277-CANTHER-Cancer Heterogeneity Plasticity and Resistance to Therapies, 59000 Lille, France; Unité Tumorigenèse et Résistance aux Traitements, Institut Pasteur de Lille, 59000 Lille, France
| | - Anne Prévotat
- University Lille, Clinique des Maladies Respiratoires, CRCM Hôpital Calmette, CHRU Lille, 59000 Lille, France
| | - Philippe Reix
- CRCM Pédiatrique Lyon, Hôpital Femme Mère Enfant, Hospices Civils de Lyon, UMR 5558 (EMET), CNRS, LBBE, Université de Lyon, 69622 Villeurbanne, France
| | - Dominique Hubert
- Pulmonary Department and Adult CF Centre, Cochin Hospital, AP-HP, Paris, France
| | - Michèle Gérardin
- CF Pediatric Centre, Robert Debré Hospital, AP-HP, 75019 Paris, France
| | - Mathias Chamaillard
- University Lille, INSERM, U1003-PHYCEL-Physiologie Cellulaire, 59000 Lille, France
| | - Natalia Prevarskaya
- University Lille, INSERM, U1003-PHYCEL-Physiologie Cellulaire, 59000 Lille, France; Laboratory of Excellence, Ion Channels Science and Therapeutics, 59655 Villeneuve d'Ascq, France
| | - Sylvie Rebuffat
- Muséum National d'Histoire Naturelle, Centre National de la Recherche Scientifique, Laboratory of Molecules of Communication and Adaptation of Microorganisms (MCAM), UMR 7245 CNRS-MNHN, CP 54, 57 Rue Cuvier, 75005 Paris, France
| | - George Shapovalov
- University Lille, INSERM, U1003-PHYCEL-Physiologie Cellulaire, 59000 Lille, France; Laboratory of Excellence, Ion Channels Science and Therapeutics, 59655 Villeneuve d'Ascq, France
| | - Jeffrey Beekman
- Pediatric Respiratory Medicine, Wilhelmina Children's Hospital, University Medical Center, Utrecht University, 3584 EA Utrecht, the Netherlands; Regenerative Medicine Utrecht, University Medical Center, Utrecht University, 3584 CT Utrecht, the Netherlands; Center for Living Technologies, University Medical Center, Utrecht University, 3584 CT Utrecht, the Netherlands
| | - Fabrice Lejeune
- University Lille, CNRS, INSERM, UMR9020-U1277-CANTHER-Cancer Heterogeneity Plasticity and Resistance to Therapies, 59000 Lille, France; Unité Tumorigenèse et Résistance aux Traitements, Institut Pasteur de Lille, 59000 Lille, France.
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6
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Kim YJ, Krainer AR. Antisense Oligonucleotide Therapeutics for Cystic Fibrosis: Recent Developments and Perspectives. Mol Cells 2023; 46:10-20. [PMID: 36697233 PMCID: PMC9880599 DOI: 10.14348/molcells.2023.2172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 11/22/2022] [Accepted: 11/23/2022] [Indexed: 01/27/2023] Open
Abstract
Antisense oligonucleotide (ASO) technology has become an attractive therapeutic modality for various diseases, including Mendelian disorders. ASOs can modulate the expression of a target gene by promoting mRNA degradation or changing pre-mRNA splicing, nonsense-mediated mRNA decay, or translation. Advances in medicinal chemistry and a deeper understanding of post-transcriptional mechanisms have led to the approval of several ASO drugs for diseases that had long lacked therapeutic options. For instance, an ASO drug called nusinersen became the first approved drug for spinal muscular atrophy, improving survival and the overall disease course. Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene cause cystic fibrosis (CF). Although Trikafta and other CFTR-modulation therapies benefit most CF patients, there is a significant unmet therapeutic need for a subset of CF patients. In this review, we introduce ASO therapies and their mechanisms of action, describe the opportunities and challenges for ASO therapeutics for CF, and discuss the current state and prospects of ASO therapies for CF.
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Affiliation(s)
- Young Jin Kim
- Department of Pediatrics, Mount Sinai Hospital, New York, NY 10029, USA
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7
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Clarke LA, Amaral MD. What Can RNA-Based Therapy Do for Monogenic Diseases? Pharmaceutics 2023; 15:pharmaceutics15010260. [PMID: 36678889 PMCID: PMC9863139 DOI: 10.3390/pharmaceutics15010260] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/04/2023] [Accepted: 01/09/2023] [Indexed: 01/13/2023] Open
Abstract
The use of RNA-based approaches to treat monogenic diseases (i.e., hereditary disorders caused by mutations in single genes) has been developed on different fronts. One approach uses small antisense oligonucleotides (ASOs) to modulate RNA processing at various stages; namely, to enhance correct splicing, to stimulate exon skipping (to exclude premature termination codon variants), to avoid undesired messenger RNA (mRNA) transcript degradation via the nonsense-mediated decay (NMD) pathway, or to induce mRNA degradation where they encode toxic proteins (e.g., in dominant diseases). Another approach consists in administering mRNA, which, like gene therapy, is a mutation-agnostic approach with potential application to any recessive monogenic disease. This is simpler than gene therapy because instead of requiring targeting of the nucleus, the mRNA only needs to be delivered to the cytoplasm. Although very promising (as demonstrated by COVID-19 vaccines), these approaches still have potential for optimisation, namely regarding delivery efficiency, adverse drug reactions and toxicity.
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8
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Jackson JJ, Mao Y, White TR, Foye C, Oliver KE. Features of CFTR mRNA and implications for therapeutics development. Front Genet 2023; 14:1166529. [PMID: 37168508 PMCID: PMC10165737 DOI: 10.3389/fgene.2023.1166529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 03/27/2023] [Indexed: 05/13/2023] Open
Abstract
Cystic fibrosis (CF) is an autosomal recessive disease impacting ∼100,000 people worldwide. This lethal disorder is caused by mutation of the CF transmembrane conductance regulator (CFTR) gene, which encodes an ATP-binding cassette-class C protein. More than 2,100 variants have been identified throughout the length of CFTR. These defects confer differing levels of severity in mRNA and/or protein synthesis, folding, gating, and turnover. Drug discovery efforts have resulted in recent development of modulator therapies that improve clinical outcomes for people living with CF. However, a significant portion of the CF population has demonstrated either no response and/or adverse reactions to small molecules. Additional therapeutic options are needed to restore underlying genetic defects for all patients, particularly individuals carrying rare or refractory CFTR variants. Concerted focus has been placed on rescuing variants that encode truncated CFTR protein, which also harbor abnormalities in mRNA synthesis and stability. The current mini-review provides an overview of CFTR mRNA features known to elicit functional consequences on final protein conformation and function, including considerations for RNA-directed therapies under investigation. Alternative exon usage in the 5'-untranslated region, polypyrimidine tracts, and other sequence elements that influence splicing are discussed. Additionally, we describe mechanisms of CFTR mRNA decay and post-transcriptional regulation mediated through interactions with the 3'-untranslated region (e.g. poly-uracil sequences, microRNAs). Contributions of synonymous single nucleotide polymorphisms to CFTR transcript utilization are also examined. Comprehensive understanding of CFTR RNA biology will be imperative for optimizing future therapeutic endeavors intended to address presently untreatable forms of CF.
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Affiliation(s)
- JaNise J. Jackson
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, United States
- Center for Cystic Fibrosis and Airways Disease Research, Emory University and Children’s Healthcare of Atlanta, Atlanta, GA, United States
| | - Yiyang Mao
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, United States
- Center for Cystic Fibrosis and Airways Disease Research, Emory University and Children’s Healthcare of Atlanta, Atlanta, GA, United States
| | - Tyshawn R. White
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, United States
- Center for Cystic Fibrosis and Airways Disease Research, Emory University and Children’s Healthcare of Atlanta, Atlanta, GA, United States
| | - Catherine Foye
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, United States
- Center for Cystic Fibrosis and Airways Disease Research, Emory University and Children’s Healthcare of Atlanta, Atlanta, GA, United States
| | - Kathryn E. Oliver
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, United States
- Center for Cystic Fibrosis and Airways Disease Research, Emory University and Children’s Healthcare of Atlanta, Atlanta, GA, United States
- *Correspondence: Kathryn E. Oliver,
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9
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Editorial overview - 2022 respiratory issue: Cystic fibrosis pathophysiology, models, and novel therapies. Curr Opin Pharmacol 2022; 67:102289. [PMID: 36152600 DOI: 10.1016/j.coph.2022.102289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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10
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Ensinck MM, Carlon MS. One Size Does Not Fit All: The Past, Present and Future of Cystic Fibrosis Causal Therapies. Cells 2022; 11:cells11121868. [PMID: 35740997 PMCID: PMC9220995 DOI: 10.3390/cells11121868] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 05/25/2022] [Accepted: 05/28/2022] [Indexed: 02/04/2023] Open
Abstract
Cystic fibrosis (CF) is the most common monogenic disorder, caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. Over the last 30 years, tremendous progress has been made in understanding the molecular basis of CF and the development of treatments that target the underlying defects in CF. Currently, a highly effective CFTR modulator treatment (Kalydeco™/Trikafta™) is available for 90% of people with CF. In this review, we will give an extensive overview of past and ongoing efforts in the development of therapies targeting the molecular defects in CF. We will discuss strategies targeting the CFTR protein (i.e., CFTR modulators such as correctors and potentiators), its cellular environment (i.e., proteostasis modulation, stabilization at the plasma membrane), the CFTR mRNA (i.e., amplifiers, nonsense mediated mRNA decay suppressors, translational readthrough inducing drugs) or the CFTR gene (gene therapies). Finally, we will focus on how these efforts can be applied to the 15% of people with CF for whom no causal therapy is available yet.
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Affiliation(s)
- Marjolein M. Ensinck
- Molecular Virology and Gene Therapy, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, 3000 Leuven, Flanders, Belgium;
| | - Marianne S. Carlon
- Molecular Virology and Gene Therapy, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, 3000 Leuven, Flanders, Belgium;
- Laboratory of Respiratory Diseases and Thoracic Surgery (BREATHE), Department of Chronic Diseases and Metabolism, KU Leuven, 3000 Leuven, Flanders, Belgium
- Correspondence:
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11
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Splicing mutations in the CFTR gene as therapeutic targets. Gene Ther 2022; 29:399-406. [PMID: 35650428 PMCID: PMC9385490 DOI: 10.1038/s41434-022-00347-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 05/07/2022] [Accepted: 05/12/2022] [Indexed: 11/08/2022]
Abstract
The marketing approval, about ten years ago, of the first disease modulator for patients with cystic fibrosis harboring specific CFTR genotypes (~5% of all patients) brought new hope for their treatment. To date, several therapeutic strategies have been approved and the number of CFTR mutations targeted by therapeutic agents is increasing. Although these drugs do not reverse the existing disease, they help to increase the median life expectancy. However, on the basis of their CFTR genotype, ~10% of patients presently do not qualify for any of the currently available CFTR modulator therapies, particularly patients with splicing mutations (~12% of the reported CFTR mutations). Efforts are currently made to develop therapeutic agents that target disease-causing CFTR variants that affect splicing. This highlights the need to fully identify them by scanning non-coding regions and systematically determine their functional consequences. In this review, we present some examples of CFTR alterations that affect splicing events and the different therapeutic options that are currently developed and tested for splice switching.
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Kim YJ, Nomakuchi T, Papaleonidopoulou F, Yang L, Zhang Q, Krainer AR. Gene-specific nonsense-mediated mRNA decay targeting for cystic fibrosis therapy. Nat Commun 2022; 13:2978. [PMID: 35624092 PMCID: PMC9142507 DOI: 10.1038/s41467-022-30668-y] [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: 07/20/2021] [Accepted: 05/06/2022] [Indexed: 12/20/2022] Open
Abstract
Low CFTR mRNA expression due to nonsense-mediated mRNA decay (NMD) is a major hurdle in developing a therapy for cystic fibrosis (CF) caused by the W1282X mutation in the CFTR gene. CFTR-W1282X truncated protein retains partial function, so increasing its levels by inhibiting NMD of its mRNA will likely be beneficial. Because NMD regulates the normal expression of many genes, gene-specific stabilization of CFTR-W1282X mRNA expression is more desirable than general NMD inhibition. Synthetic antisense oligonucleotides (ASOs) designed to prevent binding of exon junction complexes (EJC) downstream of premature termination codons (PTCs) attenuate NMD in a gene-specific manner. We describe cocktails of three ASOs that specifically increase the expression of CFTR-W1282X mRNA and CFTR protein upon delivery into human bronchial epithelial cells. This treatment increases the CFTR-mediated chloride current. These results set the stage for clinical development of an allele-specific therapy for CF caused by the W1282X mutation. The W1282X nonsense mutation in the CFTR gene causes cystic fibrosis by reducing its mRNA and functional protein levels. Here the authors developed antisense-oligonucleotide cocktails that restore CFTR protein function by gene-specific stabilization of CFTR mRNA.
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Affiliation(s)
- Young Jin Kim
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, USA.,Graduate Program in Genetics, Stony Brook University, Stony Brook, NY, 11794, USA.,Medical Scientist Training Program, Stony Brook University School of Medicine, Stony Brook, NY, 11794, USA
| | - Tomoki Nomakuchi
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, USA.,Medical Scientist Training Program, Stony Brook University School of Medicine, Stony Brook, NY, 11794, USA.,Division of Human Genetics, Children's Hospital of Philadelphia, Philadelphia, PA, 19104, USA
| | - Foteini Papaleonidopoulou
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, USA.,Francis Crick Institute, London, 1140062, UK
| | - Lucia Yang
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, USA.,Graduate Program in Genetics, Stony Brook University, Stony Brook, NY, 11794, USA.,Medical Scientist Training Program, Stony Brook University School of Medicine, Stony Brook, NY, 11794, USA
| | - Qian Zhang
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, USA.,Graduate Program in Molecular and Cell Biology, Stony Brook University, Stony Brook, NY, 11794, USA
| | - Adrian R Krainer
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, USA.
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Martinovich KM, Kicic A, Stick SM, Johnsen RD, Fletcher S, Wilton SD. Investigating the Implications of CFTR Exon Skipping Using a Cftr Exon 9 Deleted Mouse Model. Front Pharmacol 2022; 13:868863. [PMID: 35392567 PMCID: PMC8981082 DOI: 10.3389/fphar.2022.868863] [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: 02/03/2022] [Accepted: 03/07/2022] [Indexed: 11/13/2022] Open
Abstract
Introduction: Severity and disease progression in people with Cystic Fibrosis (CF) is typically dependent on their genotype. One potential therapeutic strategy for people with specific mutations is exon skipping with antisense oligonucleotides (AO). CFTR exon 9 is an in-frame exon and hence the exclusion of this exon would excise only 31 amino acids but not alter the reading frame of the remaining mRNA. Splice mutations 1209 + 1 G > C and 1209 + 2 T > G were documented to cause CFTR exon 9 skipping and these variants were reported to manifest as a milder CF disease, therefore exon 9 skipping could be beneficial for people with class I mutations that affect exon 9 such as p.Trp401X. While the impact of exon 9 skipping on gene expression and cellular pathways can be studied in cells in vitro, trace amount of full-length normal or mutated material could confound the evaluation. To overcome this limitation, the impact of CFTR exon 9 skipping on disease phenotype and severity is more effectively evaluated in a small animal model. It was hypothesised that antisense oligonucleotide-mediated skipping this particular exon could result in a "mild mouse CF phenotype". Methods: Cftr exon 9 deleted mice were generated using homologous recombination. Survival of homozygous (Cftr Δ9/Δ9 ) and heterozygous (Cftr Δ9/+ ) mice was compared to that of other CF mouse models, and lung and intestinal organ histology examined for any pathologies. Primary airway epithelial cells (pAECs) were harvested from Cftr Δ9/Δ9 mice and cultured at the Air Liquid Interface for CFTR functional assessment using Ussing Chamber analysis. Results: A Cftr Δ9/Δ9 mouse model presented with intestinal obstructions, and at time of weaning (21 days). Cftr Δ9/Δ9 mice had a survival rate of 83% that dropped to 38% by day 50. Histological sections of the small intestine from Cftr Δ9/Δ9 mice showed more goblet cells and mucus accumulation than samples from the Cftr Δ9/+ littermates. Airway epithelial cell cultures established from Cftr Δ9/Δ9 mice were not responsive to forskolin stimulation. Summary: The effect of Cftr exon 9 deletion on Cftr function was assessed and it was determined that the encoded Cftr isoform did not result in a milder "mouse CF disease phenotype," suggesting that Cftr exon 9 is not dispensable, although further investigation in human CF pAECs would be required to confirm this observation.
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Affiliation(s)
- Kelly M Martinovich
- School of Medicine, The University of Western Australia, Perth, WA, Australia.,Telethon Kids Institute, Wal-yan Respiratory Research Centre, Perth, WA, Australia.,Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute, Murdoch University, Murdoch, WA, Australia
| | - Anthony Kicic
- School of Medicine, The University of Western Australia, Perth, WA, Australia.,Telethon Kids Institute, Wal-yan Respiratory Research Centre, Perth, WA, Australia.,Centre for Cell Therapy and Regenerative Medicine, School of Medicine and Pharmacology, The University of Western Australia, Perth, WA, Australia.,Department of Respiratory and Sleep Medicine, Perth Childrens Hospital, Nedlands, WA, Australia.,School of Population Health, Curtin University, Bentley, WA, Australia
| | - Stephen M Stick
- School of Medicine, The University of Western Australia, Perth, WA, Australia.,Telethon Kids Institute, Wal-yan Respiratory Research Centre, Perth, WA, Australia.,Centre for Cell Therapy and Regenerative Medicine, School of Medicine and Pharmacology, The University of Western Australia, Perth, WA, Australia.,Department of Respiratory and Sleep Medicine, Perth Childrens Hospital, Nedlands, WA, Australia
| | - Russell D Johnsen
- Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute, Murdoch University, Murdoch, WA, Australia.,Perron Institute for Neurological and Translational Sciences, Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Nedlands, WA, Australia
| | - Sue Fletcher
- Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute, Murdoch University, Murdoch, WA, Australia.,Perron Institute for Neurological and Translational Sciences, Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Nedlands, WA, Australia.,PYC Therapeutics, Perth, WA, Australia
| | - Steve D Wilton
- Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute, Murdoch University, Murdoch, WA, Australia.,Perron Institute for Neurological and Translational Sciences, Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Nedlands, WA, Australia
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