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Welsh MJ. The arc of discovery, from the description of cystic fibrosis to effective treatments. J Clin Invest 2024; 134:e186231. [PMID: 39352390 PMCID: PMC11444155 DOI: 10.1172/jci186231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/03/2024] Open
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2
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Lakli M, Onnée M, Carrez T, Becq F, Falguières T, Fanen P. ABC transporters involved in respiratory and cholestatic diseases: From rare to very rare monogenic diseases. Biochem Pharmacol 2024; 229:116468. [PMID: 39111603 DOI: 10.1016/j.bcp.2024.116468] [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: 02/26/2024] [Revised: 07/16/2024] [Accepted: 08/03/2024] [Indexed: 08/24/2024]
Abstract
ATP-binding cassette (ABC) transporters constitute a 49-member superfamily in humans. These proteins, most of them being transmembrane, allow the active transport of an important variety of substrates across biological membranes, using ATP hydrolysis as an energy source. For an important proportion of these ABC transporters, genetic variations of the loci encoding them have been correlated with rare genetic diseases, including cystic fibrosis and interstitial lung disease (variations in CFTR/ABCC7 and ABCA3) as well as cholestatic liver diseases (variations in ABCB4 and ABCB11). In this review, we first describe these ABC transporters and how their molecular dysfunction may lead to human diseases. Then, we propose a classification of the genetic variants according to their molecular defect (expression, traffic, function and/or stability), which may be considered as a general guideline for all ABC transporters' variants. Finally, we discuss recent progress in the field of targeted pharmacotherapy, which aim to correct specific molecular defects using small molecules. In conclusion, we are opening the path to treatment repurposing for diseases involving similar deficiencies in other ABC transporters.
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Affiliation(s)
- Mounia Lakli
- Inserm, Université Paris-Saclay, Physiopathogenèse et traitement des maladies du foie, UMR_S 1193, Hepatinov, 91400 Orsay, France
| | - Marion Onnée
- Univ Paris Est Creteil, INSERM, IMRB, F-94010, Créteil, France
| | - Thomas Carrez
- Université de Poitiers, Laboratoire Physiopathologie et Régulation des Transports Ioniques, Pôle Biologie Santé, 86000 Poitiers, France; ManRos Therapeutics, Hôtel de Recherche, Centre de Perharidy, 29680, Roscoff, France
| | - Frédéric Becq
- Université de Poitiers, Laboratoire Physiopathologie et Régulation des Transports Ioniques, Pôle Biologie Santé, 86000 Poitiers, France
| | - Thomas Falguières
- Inserm, Université Paris-Saclay, Physiopathogenèse et traitement des maladies du foie, UMR_S 1193, Hepatinov, 91400 Orsay, France
| | - Pascale Fanen
- Univ Paris Est Creteil, INSERM, IMRB, F-94010, Créteil, France; AP-HP, Département de Génétique Médicale, Hôpital Henri Mondor, F-94010, Créteil, France.
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3
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Brodermann MH, Henderson EK, Sellar RS. The emerging role of targeted protein degradation to treat and study cancer. J Pathol 2024; 263:403-417. [PMID: 38886898 DOI: 10.1002/path.6301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 04/18/2024] [Accepted: 04/30/2024] [Indexed: 06/20/2024]
Abstract
The evolution of cancer treatment has provided increasingly targeted strategies both in the upfront and relapsed disease settings. Small-molecule inhibitors and immunotherapy have risen to prominence with chimeric antigen receptor T-cells, checkpoint inhibitors, kinase inhibitors, and monoclonal antibody therapies being deployed across a range of solid organ and haematological malignancies. However, novel approaches are required to target transcription factors and oncogenic fusion proteins that are central to cancer biology and have generally eluded successful drug development. Thalidomide analogues causing protein degradation have been a cornerstone of treatment in multiple myeloma, but a lack of in-depth mechanistic understanding initially limited progress in the field. When the protein cereblon (CRBN) was found to mediate thalidomide analogues' action and CRBN's neo-targets were identified, existing and novel drug development accelerated, with applications outside multiple myeloma, including non-Hodgkin's lymphoma, myelodysplastic syndrome, and acute leukaemias. Critically, transcription factors were the first canonical targets described. In addition to broadening the application of protein-degrading drugs, resistance mechanisms are being overcome and targeted protein degradation is widening the scope of druggable proteins against which existing approaches have been ineffective. Examples of targeted protein degraders include molecular glues and proteolysis targeting chimeras (PROTACs): heterobifunctional molecules that bind to proteins of interest and cause proximity-induced ubiquitination and proteasomal degradation via a linked E3 ligase. Twenty years since their inception, PROTACs have begun progressing through clinical trials, with early success in targeting the oestrogen receptor and androgen receptor in breast and prostate cancer respectively. This review explores important developments in targeted protein degradation to both treat and study cancer. It also considers the potential advantages and challenges in the translational aspects of developing new treatments. © 2024 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.
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Affiliation(s)
| | - Elizabeth K Henderson
- Department of Haematology, UCL Cancer Institute, University College London, London, UK
| | - Rob S Sellar
- Department of Haematology, UCL Cancer Institute, University College London, London, UK
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4
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Hong JS, Tindall JM, Tindall SR, Sorscher EJ. Mutation accumulation in H. sapiens F508del CFTR countermands dN/dS type genomic analysis. PLoS One 2024; 19:e0305832. [PMID: 39024311 PMCID: PMC11257350 DOI: 10.1371/journal.pone.0305832] [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: 01/06/2024] [Accepted: 06/05/2024] [Indexed: 07/20/2024] Open
Abstract
Understanding the mechanisms that underlie de novo mutations (DNMs) can be essential for interpreting human evolution, including aspects such as rapidly diverging genes, conservation of non-coding regulatory elements, and somatic DNA adaptation, among others. DNM accumulation in Homo sapiens is often limited to evaluation of human trios or quads across a single generation. Moreover, human SNPs in exons, pseudogenes, or other non-coding elements can be ancient and difficult to date, including polymorphisms attributable to founder effects and identity by descent. In this report, we describe multigenerational evolution of a human coding locus devoid of natural selection, and delineate patterns and principles by which DNMs have accumulated over the past few thousand years. We apply a data set comprising cystic fibrosis transmembrane conductance regulator (CFTR) alleles from 2,393 individuals homozygous for the F508del defect. Additional polymorphism on the F508del background diversified subsequent to a single mutational event during recent human history. Because F508del CFTR is without function, SNPs observed on this haplotype are effectively attributable to factors that govern accumulating de novo mutations. We show profound enhancement of transition, synonymous, and positionally repetitive polymorphisms, indicating appearance of DNMs in a manner evolutionarily designed to protect protein coding DNA against mutational attrition while promoting diversity.
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Affiliation(s)
- Jeong S. Hong
- Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Janice M. Tindall
- Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Samuel R. Tindall
- Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Eric J. Sorscher
- Emory University School of Medicine, Atlanta, Georgia, United States of America
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5
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van der Sluijs P, Hoelen H, Schmidt A, Braakman I. The Folding Pathway of ABC Transporter CFTR: Effective and Robust. J Mol Biol 2024; 436:168591. [PMID: 38677493 DOI: 10.1016/j.jmb.2024.168591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Revised: 04/16/2024] [Accepted: 04/23/2024] [Indexed: 04/29/2024]
Abstract
De novo protein folding into a native three-dimensional structure is indispensable for biological function, is instructed by its amino acid sequence, and occurs along a vectorial trajectory. The human proteome contains thousands of membrane-spanning proteins, whose biosynthesis begins on endoplasmic reticulum-associated ribosomes. Nearly half of all membrane proteins traverse the membrane more than once, including therapeutically important protein families such as solute carriers, G-protein-coupled receptors, and ABC transporters. These mediate a variety of functions like signal transduction and solute transport and are often of vital importance for cell function and tissue homeostasis. Missense mutations in multispan membrane proteins can lead to misfolding and cause disease; an example is the ABC transporter Cystic Fibrosis Transmembrane Conductance Regulator (CFTR). Even though our understanding of multispan membrane-protein folding still is rather rudimental, the cumulative knowledge of 20 years of basic research on CFTR folding has led to development of drugs that modulate the misfolded protein. This has provided the prospect of a life without CF to the vast majority of patients. In this review we describe our understanding of the folding pathway of CFTR in cells, which is modular and tolerates many defects, making it effective and robust. We address how modulator drugs affect folding and function of CFTR, and distinguish protein stability from its folding process. Since the domain architecture of (mammalian) ABC transporters are highly conserved, we anticipate that the insights we discuss here for folding of CFTR may lay the groundwork for understanding the general rules of ABC-transporter folding.
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Affiliation(s)
- Peter van der Sluijs
- Cellular Protein Chemistry, Bijvoet Centre for Biomolecular Research, Utrecht University, 3584 CH Utrecht, the Netherlands.
| | - Hanneke Hoelen
- Cellular Protein Chemistry, Bijvoet Centre for Biomolecular Research, Utrecht University, 3584 CH Utrecht, the Netherlands; Present address: GenDx, Yalelaan 48, 3584 CM Utrecht, The Netherlands
| | - Andre Schmidt
- Cellular Protein Chemistry, Bijvoet Centre for Biomolecular Research, Utrecht University, 3584 CH Utrecht, the Netherlands; 3D-Pharmxchange, Tilburg, the Netherlands
| | - Ineke Braakman
- Cellular Protein Chemistry, Bijvoet Centre for Biomolecular Research, Utrecht University, 3584 CH Utrecht, the Netherlands
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6
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Sousa AA, Hemez C, Lei L, Traore S, Kulhankova K, Newby GA, Doman JL, Oye K, Pandey S, Karp PH, McCray PB, Liu DR. Systematic optimization of prime editing for the efficient functional correction of CFTR F508del in human airway epithelial cells. Nat Biomed Eng 2024:10.1038/s41551-024-01233-3. [PMID: 38987629 DOI: 10.1038/s41551-024-01233-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Accepted: 06/12/2024] [Indexed: 07/12/2024]
Abstract
Prime editing (PE) enables precise and versatile genome editing without requiring double-stranded DNA breaks. Here we describe the systematic optimization of PE systems to efficiently correct human cystic fibrosis (CF) transmembrane conductance regulator (CFTR) F508del, a three-nucleotide deletion that is the predominant cause of CF. By combining six efficiency optimizations for PE-engineered PE guide RNAs, the PEmax architecture, the transient expression of a dominant-negative mismatch repair protein, strategic silent edits, PE6 variants and proximal 'dead' single-guide RNAs-we increased correction efficiencies for CFTR F508del from less than 0.5% in HEK293T cells to 58% in immortalized bronchial epithelial cells (a 140-fold improvement) and to 25% in patient-derived airway epithelial cells. The optimizations also resulted in minimal off-target editing, in edit-to-indel ratios 3.5-fold greater than those achieved by nuclease-mediated homology-directed repair, and in the functional restoration of CFTR ion channels to over 50% of wild-type levels (similar to those achieved via combination treatment with elexacaftor, tezacaftor and ivacaftor) in primary airway cells. Our findings support the feasibility of a durable one-time treatment for CF.
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Affiliation(s)
- Alexander A Sousa
- Merkin Institute of Transformative Technologies in Healthcare, The Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA
| | - Colin Hemez
- Merkin Institute of Transformative Technologies in Healthcare, The Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA
| | - Lei Lei
- Stead Family Department of Pediatrics and Pappajohn Biomedical Institute, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Soumba Traore
- Stead Family Department of Pediatrics and Pappajohn Biomedical Institute, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Katarina Kulhankova
- Stead Family Department of Pediatrics and Pappajohn Biomedical Institute, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Gregory A Newby
- Merkin Institute of Transformative Technologies in Healthcare, The Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA
- Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Jordan L Doman
- Merkin Institute of Transformative Technologies in Healthcare, The Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA
| | - Keyede Oye
- Merkin Institute of Transformative Technologies in Healthcare, The Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA
| | - Smriti Pandey
- Merkin Institute of Transformative Technologies in Healthcare, The Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA
| | - Philip H Karp
- Department of Internal Medicine and Pappajohn Biomedical Institute, Roy J. and Lucille A. Carver College of Medicine, Iowa City, IA, USA
- Howard Hughes Medical Institute, University of Iowa, Iowa City, IA, USA
| | - Paul B McCray
- Stead Family Department of Pediatrics and Pappajohn Biomedical Institute, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - David R Liu
- Merkin Institute of Transformative Technologies in Healthcare, The Broad Institute of MIT and Harvard, Cambridge, MA, USA.
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA.
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA.
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7
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Tanjala AC, Jiang JX, Eckford PDW, Ramjeesingh M, Li C, Huan LJ, Langeveld G, Townsend C, Paone DV, Busch-Petersen J, Pekhletski R, Tang L, Raju V, Rowe SM, Bear CE. Comparison of a novel potentiator of CFTR channel activity to ivacaftor in ameliorating mucostasis caused by cigarette smoke in primary human bronchial airway epithelial cells. Respir Res 2024; 25:269. [PMID: 38982492 PMCID: PMC11234710 DOI: 10.1186/s12931-024-02889-w] [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: 12/31/2023] [Accepted: 06/19/2024] [Indexed: 07/11/2024] Open
Abstract
BACKGROUND Cystic Fibrosis causing mutations in the gene CFTR, reduce the activity of the CFTR channel protein, and leads to mucus aggregation, airway obstruction and poor lung function. A role for CFTR in the pathogenesis of other muco-obstructive airway diseases such as Chronic Obstructive Pulmonary Disease (COPD) has been well established. The CFTR modulatory compound, Ivacaftor (VX-770), potentiates channel activity of CFTR and certain CF-causing mutations and has been shown to ameliorate mucus obstruction and improve lung function in people harbouring these CF-causing mutations. A pilot trial of Ivacaftor supported its potential efficacy for the treatment of mucus obstruction in COPD. These findings prompted the search for CFTR potentiators that are more effective in ameliorating cigarette-smoke (CS) induced mucostasis. METHODS Small molecule potentiators, previously identified in CFTR binding studies, were tested for activity in augmenting CFTR channel activity using patch clamp electrophysiology in HEK-293 cells, a fluorescence-based assay of membrane potential in Calu-3 cells and in Ussing chamber studies of primary bronchial epithelial cultures. Addition of cigarette smoke extract (CSE) to the solutions bathing the apical surface of Calu-3 cells and primary bronchial airway cultures was used to model COPD. Confocal studies of the velocity of fluorescent microsphere movement on the apical surface of CSE exposed airway epithelial cultures, were used to assess the effect of potentiators on CFTR-mediated mucociliary movement. RESULTS We showed that SK-POT1, like VX-770, was effective in augmenting the cyclic AMP-dependent channel activity of CFTR. SK-POT-1 enhanced CFTR channel activity in airway epithelial cells previously exposed to CSE and ameliorated mucostasis on the surface of primary airway cultures. CONCLUSION Together, this evidence supports the further development of SK-POT1 as an intervention in the treatment of COPD.
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Affiliation(s)
| | - Jia Xin Jiang
- Program in Molecular Medicine, Research Institute, Hospital for Sick Children, Toronto, Canada
| | - Paul D W Eckford
- Program in Molecular Medicine, Research Institute, Hospital for Sick Children, Toronto, Canada
| | - Mohabir Ramjeesingh
- Program in Molecular Medicine, Research Institute, Hospital for Sick Children, Toronto, Canada
| | - Canhui Li
- Program in Molecular Medicine, Research Institute, Hospital for Sick Children, Toronto, Canada
| | - Ling Jun Huan
- Program in Molecular Medicine, Research Institute, Hospital for Sick Children, Toronto, Canada
| | - Gabrielle Langeveld
- Program in Molecular Medicine, Research Institute, Hospital for Sick Children, Toronto, Canada
| | | | | | | | - Roman Pekhletski
- Program in Molecular Medicine, Research Institute, Hospital for Sick Children, Toronto, Canada
| | - LiPing Tang
- Department of Medicine, Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Vamsee Raju
- Department of Medicine, Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Steven M Rowe
- Department of Medicine, Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Christine E Bear
- Program in Molecular Medicine, Research Institute, Hospital for Sick Children, Toronto, Canada.
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8
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Kamada Y, Ohnishi Y, Nakashima C, Fujii A, Terakawa M, Hamano I, Nakayamada U, Katoh S, Hirata N, Tateishi H, Fukuda R, Takahashi H, Lukacs GL, Okiyoneda T. HERC3 facilitates ERAD of select membrane proteins by recognizing membrane-spanning domains. J Cell Biol 2024; 223:e202308003. [PMID: 38722278 PMCID: PMC11082371 DOI: 10.1083/jcb.202308003] [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: 08/01/2023] [Revised: 02/22/2024] [Accepted: 03/18/2024] [Indexed: 05/12/2024] Open
Abstract
Aberrant proteins located in the endoplasmic reticulum (ER) undergo rapid ubiquitination by multiple ubiquitin (Ub) E3 ligases and are retrotranslocated to the cytosol as part of the ER-associated degradation (ERAD). Despite several ERAD branches involving different Ub E3 ligases, the molecular machinery responsible for these ERAD branches in mammalian cells remains not fully understood. Through a series of multiplex knockdown/knockout experiments with real-time kinetic measurements, we demonstrate that HERC3 operates independently of the ER-embedded ubiquitin ligases RNF5 and RNF185 (RNF5/185) to mediate the retrotranslocation and ERAD of misfolded CFTR. While RNF5/185 participates in the ERAD process of both misfolded ABCB1 and CFTR, HERC3 uniquely promotes CFTR ERAD. In vitro assay revealed that HERC3 directly interacts with the exposed membrane-spanning domains (MSDs) of CFTR but not with the MSDs embedded in liposomes. Therefore, HERC3 could play a role in the quality control of MSDs in the cytoplasm and might be crucial for the ERAD pathway of select membrane proteins.
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Affiliation(s)
- Yuka Kamada
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda, Japan
| | - Yuko Ohnishi
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda, Japan
| | - Chikako Nakashima
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda, Japan
| | - Aika Fujii
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda, Japan
| | - Mana Terakawa
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda, Japan
| | - Ikuto Hamano
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda, Japan
| | - Uta Nakayamada
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda, Japan
| | - Saori Katoh
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda, Japan
| | - Noriaki Hirata
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda, Japan
| | - Hazuki Tateishi
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda, Japan
| | - Ryosuke Fukuda
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda, Japan
| | - Hirotaka Takahashi
- Division of Cell-Free Sciences, Proteo-Science Center (PROS), Ehime University, Matsuyama, Japan
| | - Gergely L. Lukacs
- Department of Physiology, McGill University, Montréal, Canada
- Department of Biochemistry, McGill University, Montréal, Canada
| | - Tsukasa Okiyoneda
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda, Japan
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9
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Liu A, Chokshi M, Nguyen N, Powell RT, Stephan CC, Bao G. Cystic fibrosis cell models for high-throughput analysis and drug screening. J Cyst Fibros 2024; 23:716-724. [PMID: 39060183 DOI: 10.1016/j.jcf.2024.07.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 05/24/2024] [Accepted: 07/01/2024] [Indexed: 07/28/2024]
Abstract
Cystic fibrosis (CF) is a single-gene disorder that affects the lung, digestive system, and other organs. Mutations in the CF transmembrane conductance regulator (CFTR) gene are classified into several classes based on their pathogenic mechanism and clinical severity. The distinct and heterogeneous clinical behavior of each CF class and the respective CFTR mutations have made the development of a durable therapy for all CF patients extremely challenging. While the FDA-approved drug elexacaftor/tezacaftor/ivacaftor (Trikafta) benefits CF patients carrying at least one F508del mutation in CFTR, it's not effective for many CF patients carrying a variety of other CFTR mutations. To establish a better understanding of CF pathophysiology and aid the development of novel therapeutics for different classes of CF patients, we have created four CF-mutation-specific cell models that recapitulate respectively four distinct CF classes and disease phenotypes, as confirmed by sequencing, CFTR mRNA and protein quantification. The channel function of each cell model was first validated using a well-established FLIPR (Fluorescent Imaging Plate Reader) membrane potential assay and then assessed by the YFP-based functional assay. Integrated with a halide-sensitive fluorescent reporter, these CF cell models can be used for high-throughput drug screening, as demonstrated by a proof-of-concept study using Trikafta. These cell models have the potential to advance CFTR mutation-specific therapies thus addressing the unmet needs of CF patients with rare mutations.
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Affiliation(s)
- Aidi Liu
- Department of Bioengineering, Rice University, Houston, Texas 77030, USA
| | - Mithil Chokshi
- Department of Bioengineering, Rice University, Houston, Texas 77030, USA
| | - Nghi Nguyen
- Institute of Biosciences and Technology, Texas A&M University, Houston, Texas, 77030, USA
| | - Reid T Powell
- Institute of Biosciences and Technology, Texas A&M University, Houston, Texas, 77030, USA
| | - Clifford C Stephan
- Institute of Biosciences and Technology, Texas A&M University, Houston, Texas, 77030, USA
| | - Gang Bao
- Department of Bioengineering, Rice University, Houston, Texas 77030, USA.
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10
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Okiyoneda T, Borgo C, Bosello Travain V, Pedemonte N, Salvi M. Targeting ubiquitination machinery in cystic fibrosis: Where do we stand? Cell Mol Life Sci 2024; 81:271. [PMID: 38888668 PMCID: PMC11335196 DOI: 10.1007/s00018-024-05295-z] [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: 03/27/2024] [Revised: 05/16/2024] [Accepted: 05/25/2024] [Indexed: 06/20/2024]
Abstract
Cystic Fibrosis (CF) is a genetic disease caused by mutations in CFTR gene expressing the anion selective channel CFTR located at the plasma membrane of different epithelial cells. The most commonly investigated variant causing CF is F508del. This mutation leads to structural defects in the CFTR protein, which are recognized by the endoplasmic reticulum (ER) quality control system. As a result, the protein is retained in the ER and degraded via the ubiquitin-proteasome pathway. Although blocking ubiquitination to stabilize the CFTR protein has long been considered a potential pharmacological approach in CF, progress in this area has been relatively slow. Currently, no compounds targeting this pathway have entered clinical trials for CF. On the other hand, the emergence of Orkambi initially, and notably the subsequent introduction of Trikafta/Kaftrio, have demonstrated the effectiveness of molecular chaperone-based therapies for patients carrying the F508del variant and even showed efficacy against other variants. These treatments directly target the CFTR variant protein without interfering with cell signaling pathways. This review discusses the limits and potential future of targeting protein ubiquitination in CF.
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Affiliation(s)
- Tsukasa Okiyoneda
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Hyogo, 669-1330, Japan.
| | - Christian Borgo
- Department of Biomedical Sciences, University of Padova, 35131, Padova, Italy
- Department of Medicine, University of Padova, 35128, Padova, Italy
| | | | - Nicoletta Pedemonte
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, Via Gerolamo Gaslini 5, 16147, Genoa, Italy
| | - Mauro Salvi
- Department of Biomedical Sciences, University of Padova, 35131, Padova, Italy.
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11
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Evans IA, Sun X, Liang B, Vegter AR, Guo L, Lynch TJ, Zhang Y, Zhang Y, Yi Y, Yang Y, Feng Z, Park SY, Shonka A, McCumber H, Qi L, Wu P, Liu G, Lacina A, Wang K, Gibson-Corley KN, Meyerholz DK, Limoli DH, Rosen BH, Yan Z, Bartels DJ, Engelhardt JF. In utero and postnatal ivacaftor/lumacaftor therapy rescues multiorgan disease in CFTR-F508del ferrets. JCI Insight 2024; 9:e157229. [PMID: 38646935 PMCID: PMC11141870 DOI: 10.1172/jci.insight.157229] [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: 12/20/2023] [Accepted: 03/13/2024] [Indexed: 04/25/2024] Open
Abstract
Cystic fibrosis (CF) is caused by mutations in the CF transmembrane conductance regulator (CFTR) gene, with F508del being the most prevalent mutation. The combination of CFTR modulators (potentiator and correctors) has provided benefit to CF patients carrying the F508del mutation; however, the safety and effectiveness of in utero combination modulator therapy remains unclear. We created a F508del ferret model to test whether ivacaftor/lumacaftor (VX-770/VX-809) therapy can rescue in utero and postnatal pathologies associated with CF. Using primary intestinal organoids and air-liquid interface cultures of airway epithelia, we demonstrate that the F508del mutation in ferret CFTR results in a severe folding and trafficking defect, which can be partially restored by treatment with CFTR modulators. In utero treatment of pregnant jills with ivacaftor/lumacaftor prevented meconium ileus at birth in F508del kits and sustained postnatal treatment of CF offspring improved survival and partially protected from pancreatic insufficiency. Withdrawal of ivacaftor/lumacaftor treatment from juvenile CF ferrets reestablished pancreatic and lung diseases, with altered pulmonary mechanics. These findings suggest that in utero intervention with a combination of CFTR modulators may provide therapeutic benefits to individuals with F508del. This CFTR-F508del ferret model may be useful for testing therapies using clinically translatable endpoints.
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Affiliation(s)
| | | | - Bo Liang
- Department of Anatomy and Cell Biology, and
| | | | - Lydia Guo
- Department of Anatomy and Cell Biology, and
| | | | | | | | - Yaling Yi
- Department of Anatomy and Cell Biology, and
| | - Yu Yang
- Department of Anatomy and Cell Biology, and
| | - Zehua Feng
- Department of Anatomy and Cell Biology, and
| | | | | | | | - Lisi Qi
- Department of Anatomy and Cell Biology, and
| | - Peipei Wu
- Department of Anatomy and Cell Biology, and
| | | | | | - Kai Wang
- Department of Biostatistics, University of Iowa College of Public Health, Iowa City, Iowa, USA
| | - Katherine N. Gibson-Corley
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - David K. Meyerholz
- Department of Pathology, University of Iowa Carver College of Medicine, Iowa City, Iowa, USA
| | - Dominique H. Limoli
- Department of Microbiology and Immunology, University of Iowa Carver College of Medicine, Iowa City, Iowa, USA
| | - Bradley H. Rosen
- Department of Anatomy and Cell Biology, and
- Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa, USA
| | - Ziying Yan
- Department of Anatomy and Cell Biology, and
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12
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Piccolo D, Zarouchlioti C, Bellingham J, Guarascio R, Ziaka K, Molday RS, Cheetham ME. A Proximity Complementation Assay to Identify Small Molecules That Enhance the Traffic of ABCA4 Misfolding Variants. Int J Mol Sci 2024; 25:4521. [PMID: 38674104 PMCID: PMC11050442 DOI: 10.3390/ijms25084521] [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: 02/29/2024] [Revised: 04/16/2024] [Accepted: 04/18/2024] [Indexed: 04/28/2024] Open
Abstract
ABCA4-related retinopathy is the most common inherited Mendelian eye disorder worldwide, caused by biallelic variants in the ATP-binding cassette transporter ABCA4. To date, over 2200 ABCA4 variants have been identified, including missense, nonsense, indels, splice site and deep intronic defects. Notably, more than 60% are missense variants that can lead to protein misfolding, mistrafficking and degradation. Currently no approved therapies target ABCA4. In this study, we demonstrate that ABCA4 misfolding variants are temperature-sensitive and reduced temperature growth (30 °C) improves their traffic to the plasma membrane, suggesting the folding of these variants could be rescuable. Consequently, an in vitro platform was developed for the rapid and robust detection of ABCA4 traffic to the plasma membrane in transiently transfected cells. The system was used to assess selected candidate small molecules that were reported to improve the folding or traffic of other ABC transporters. Two candidates, 4-PBA and AICAR, were identified and validated for their ability to enhance both wild-type ABCA4 and variant trafficking to the cell surface in cell culture. We envision that this platform could serve as a primary screen for more sophisticated in vitro testing, enabling the discovery of breakthrough agents to rescue ABCA4 protein defects and mitigate ABCA4-related retinopathy.
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Affiliation(s)
- Davide Piccolo
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; (D.P.); (C.Z.); (R.G.); (K.Z.)
| | - Christina Zarouchlioti
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; (D.P.); (C.Z.); (R.G.); (K.Z.)
| | - James Bellingham
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; (D.P.); (C.Z.); (R.G.); (K.Z.)
| | - Rosellina Guarascio
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; (D.P.); (C.Z.); (R.G.); (K.Z.)
| | - Kalliopi Ziaka
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; (D.P.); (C.Z.); (R.G.); (K.Z.)
| | - Robert S. Molday
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC V6T 1Z3, Canada;
| | - Michael E. Cheetham
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; (D.P.); (C.Z.); (R.G.); (K.Z.)
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13
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Taniguchi S, Berenger F, Doi Y, Mimura A, Yamanishi Y, Okiyoneda T. Ligand-based virtual-screening identified a novel CFTR ligand which improves the defective cell surface expression of misfolded ABC transporters. Front Pharmacol 2024; 15:1370676. [PMID: 38666024 PMCID: PMC11043560 DOI: 10.3389/fphar.2024.1370676] [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: 01/15/2024] [Accepted: 04/01/2024] [Indexed: 04/28/2024] Open
Abstract
Cystic fibrosis (CF) is a monogenetic disease caused by the mutation of CFTR, a cAMP-regulated Cl- channel expressing at the apical plasma membrane (PM) of epithelia. ∆F508-CFTR, the most common mutant in CF, fails to reach the PM due to its misfolding and premature degradation at the endoplasmic reticulum (ER). Recently, CFTR modulators have been developed to correct CFTR abnormalities, with some being used as therapeutic agents for CF treatment. One notable example is Trikafta, a triple combination of CFTR modulators (TEZ/ELX/IVA), which significantly enhances the functionality of ΔF508-CFTR on the PM. However, there's room for improvement in its therapeutic effectiveness since TEZ/ELX/IVA doesn't fully stabilize ΔF508-CFTR on the PM. To discover new CFTR modulators, we conducted a virtual screening of approximately 4.3 million compounds based on the chemical structures of existing CFTR modulators. This effort led us to identify a novel CFTR ligand named FR3. Unlike clinically available CFTR modulators, FR3 appears to operate through a distinct mechanism of action. FR3 enhances the functional expression of ΔF508-CFTR on the apical PM in airway epithelial cell lines by stabilizing NBD1. Notably, FR3 counteracted the degradation of mature ΔF508-CFTR, which still occurs despite the presence of TEZ/ELX/IVA. Furthermore, FR3 corrected the defective PM expression of a misfolded ABCB1 mutant. Therefore, FR3 may be a potential lead compound for addressing diseases resulting from the misfolding of ABC transporters.
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Affiliation(s)
- Shogo Taniguchi
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Nishinomiya, Japan
| | - Francois Berenger
- Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan
| | - Yukako Doi
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Nishinomiya, Japan
| | - Ayana Mimura
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Nishinomiya, Japan
| | - Yoshihiro Yamanishi
- Department of Complex Systems Science, Graduate School of Informatics, Nagoya University, Graduate School of Informatics, Nagoya University, Nagoya, Japan
| | - Tsukasa Okiyoneda
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Nishinomiya, Japan
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14
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Ramananda Y, Naren AP, Arora K. Functional Consequences of CFTR Interactions in Cystic Fibrosis. Int J Mol Sci 2024; 25:3384. [PMID: 38542363 PMCID: PMC10970640 DOI: 10.3390/ijms25063384] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 03/09/2024] [Accepted: 03/12/2024] [Indexed: 09/01/2024] Open
Abstract
Cystic fibrosis (CF) is a fatal autosomal recessive disorder caused by the loss of function mutations within a single gene for the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR). CFTR is a chloride channel that regulates ion and fluid transport across various epithelia. The discovery of CFTR as the CF gene and its cloning in 1989, coupled with extensive research that went into the understanding of the underlying biological mechanisms of CF, have led to the development of revolutionary therapies in CF that we see today. The highly effective modulator therapies have increased the survival rates of CF patients and shifted the epidemiological landscape and disease prognosis. However, the differential effect of modulators among CF patients and the presence of non-responders and ineligible patients underscore the need to develop specialized and customized therapies for a significant number of patients. Recent advances in the understanding of the CFTR structure, its expression, and defined cellular compositions will aid in developing more precise therapies. As the lifespan of CF patients continues to increase, it is becoming critical to clinically address the extra-pulmonary manifestations of CF disease to improve the quality of life of the patients. In-depth analysis of the molecular signature of different CF organs at the transcriptional and post-transcriptional levels is rapidly advancing and will help address the etiological causes and variability of CF among patients and develop precision medicine in CF. In this review, we will provide an overview of CF disease, leading to the discovery and characterization of CFTR and the development of CFTR modulators. The later sections of the review will delve into the key findings derived from single-molecule and single-cell-level analyses of CFTR, followed by an exploration of disease-relevant protein complexes of CFTR that may ultimately define the etiological course of CF disease.
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Affiliation(s)
- Yashaswini Ramananda
- Department of Pediatrics, Division of Pulmonary Medicine, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA;
- Department of Medicine, Division of Pulmonary and Critical Care Medicine, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Anjaparavanda P. Naren
- Department of Pediatrics, Division of Pulmonary Medicine, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA;
- Department of Medicine, Division of Pulmonary and Critical Care Medicine, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Kavisha Arora
- Department of Medicine, Division of Pulmonary and Critical Care Medicine, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
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15
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Ferreira FC, Amaral MD, Bacalhau M, Lopes-Pacheco M. PTI-801 (posenacaftor) shares a common mechanism with VX-445 (elexacaftor) to rescue p.Phe508del-CFTR. Eur J Pharmacol 2024; 967:176390. [PMID: 38336013 DOI: 10.1016/j.ejphar.2024.176390] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 01/05/2024] [Accepted: 02/01/2024] [Indexed: 02/12/2024]
Abstract
The deletion of a phenylalanine at position 508 (p.Phe508del) in the CFTR anion channel is the most prevalent variant in people with Cystic Fibrosis (CF). This variant impairs folding and stability of the CF transmembrane conductance regulator (CFTR) protein, resulting in its defective trafficking and premature degradation. Over the last years, therapeutic accomplishments have been attained in developing small molecules that partially correct p.Phe508del-CFTR defects; however, the mechanism of action (MoA) of these compounds has only started to be uncovered. In this study, we employed biochemical, fluorescence microscopy, and functional assays to examine the efficacy and properties of PTI-801, a newly developed p.Phe508del-CFTR corrector. To exploit its MoA, we assessed PTI-801 effects in combination with low temperature, genetic revertants of p.Phe508del-CFTR (the in cis p.Val510Asp, p.Gly550Glu, p.Arg1070Trp, and 4RK) and other correctors. Our results demonstrated that PTI-801 rescues p.Phe508del-CFTR processing, PM trafficking, and channel function (upon agonist stimulation) with greater correction effects in combination with ABBV-2222, FDL-169, VX-661, or VX-809, but not with VX-445. Although PTI-801 exhibited no potentiator activity on low temperature- and corrector-rescued p.Phe508del-CFTR, this compound displayed similar behavior to that of VX-445 on genetic revertants. Such evidence associated with the lack of additivity when PTI-801 and VX-445 were combined indicates that they share a common binding site to correct p.Phe508del-CFTR defects. Despite the high efficacy of PTI-801 in combination with ABBV-2222, FDL-169, VX-661, or VX-809, these dual corrector combinations only partially restored p.Phe508del-CFTR conformational stability, as shown by the lower half-life of the mutant protein compared to that of WT-CFTR. In summary, PTI-801 likely shares a common MoA with VX-445 in rescuing p.Phe508del-CFTR, thus being a feasible alternative for the development of novel corrector combinations with greater capacity to rescue mutant CFTR folding and stability.
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Affiliation(s)
- Filipa C Ferreira
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisbon, 1749-016, Lisbon, Portugal
| | - Margarida D Amaral
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisbon, 1749-016, Lisbon, Portugal
| | - Mafalda Bacalhau
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisbon, 1749-016, Lisbon, Portugal
| | - Miquéias Lopes-Pacheco
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisbon, 1749-016, Lisbon, Portugal.
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16
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Tanjala AC, Jiang JX, Eckford PDW, Ramjeesingh M, Li C, Huan LJ, Langeveld G, Townsend C, Paone DV, Busch-Petersen J, Pekhletski R, Tang L, Raju V, Rowe SM, Bear CE. Comparison of a novel potentiator of CFTR channel activity to ivacaftor in ameliorating mucostasis caused by cigarette smoke in primary human bronchial airway epithelial cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.01.582742. [PMID: 38496440 PMCID: PMC10942391 DOI: 10.1101/2024.03.01.582742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
Background Cystic Fibrosis causing mutations in the gene CFTR , reduce the activity of the CFTR channel protein, and leads to mucus aggregation, airway obstruction and poor lung function. A role for CFTR in the pathogenesis of other muco-obstructive airway diseases such as Chronic Obstructive Pulmonary Disease (COPD) has been well established. The CFTR modulatory compound, Ivacaftor (VX-770), potentiates channel activity of CFTR and certain CF-causing mutations and has been shown to ameliorate mucus obstruction and improve lung function in people harbouring these CF-causing mutations. A pilot trial of Ivacaftor supported its potential efficacy for the treatment of mucus obstruction in COPD. These findings prompted the search for CFTR potentiators that are more effective in ameliorating cigarette-smoke (CS) induced mucostasis. Methods A novel small molecule potentiator (SK-POT1), previously identified in CFTR binding studies, was tested for its activity in augmenting CFTR channel activity using patch clamp electrophysiology in HEK-293 cells, a fluorescence-based assay of membrane potential in Calu-3 cells and in Ussing chamber studies of primary bronchial epithelial cultures. Addition of cigarette smoke extract (CSE) to the solutions bathing the apical surface of Calu-3 cells and primary bronchial airway cultures was used to model COPD. Confocal studies of the velocity of fluorescent microsphere movement on the apical surface of CSE exposed airway epithelial cultures, were used to assess the effect of potentiators on CFTR-mediated mucociliary movement. Results We showed that SK-POT1, like VX-770, was effective in augmenting the cyclic AMP-dependent channel activity of CFTR. SK-POT-1 enhanced CFTR channel activity in airway epithelial cells previously exposed to CSE and ameliorated mucostasis on the surface of primary airway cultures. Conclusion Together, this evidence supports the further development of SK-POT1 as an intervention in the treatment of COPD.
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17
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Riepe C, Wąchalska M, Deol KK, Amaya AK, Porteus MH, Olzmann JA, Kopito RR. Small-molecule correctors divert CFTR-F508del from ERAD by stabilizing sequential folding states. Mol Biol Cell 2024; 35:ar15. [PMID: 38019608 PMCID: PMC10881158 DOI: 10.1091/mbc.e23-08-0336] [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: 09/18/2023] [Revised: 11/13/2023] [Accepted: 11/20/2023] [Indexed: 12/01/2023] Open
Abstract
Over 80% of people with cystic fibrosis (CF) carry the F508del mutation in the cystic fibrosis transmembrane conductance regulator (CFTR), a chloride ion channel at the apical plasma membrane (PM) of epithelial cells. F508del impairs CFTR folding causing it to be destroyed by endoplasmic reticulum associated degradation (ERAD). Small-molecule correctors, which act as pharmacological chaperones to divert CFTR-F508del from ERAD, are the primary strategy for treating CF, yet corrector development continues with only a rudimentary understanding of how ERAD targets CFTR-F508del. We conducted genome-wide CRISPR/Cas9 knockout screens to systematically identify the molecular machinery that underlies CFTR-F508del ERAD. Although the ER-resident ubiquitin ligase, RNF5 was the top E3 hit, knocking out RNF5 only modestly reduced CFTR-F508del degradation. Sublibrary screens in an RNF5 knockout background identified RNF185 as a redundant ligase and demonstrated that CFTR-F508del ERAD is robust. Gene-drug interaction experiments illustrated that correctors tezacaftor (VX-661) and elexacaftor (VX-445) stabilize sequential, RNF5-resistant folding states. We propose that binding of correctors to nascent CFTR-F508del alters its folding landscape by stabilizing folding states that are not substrates for RNF5-mediated ubiquitylation.
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Affiliation(s)
- Celeste Riepe
- Department of Biology, Stanford University, Stanford, CA 94305
| | - Magda Wąchalska
- Department of Biology, Stanford University, Stanford, CA 94305
| | - Kirandeep K. Deol
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, CA 94720
- Chan Zuckerberg Biohub Network, San Francisco, CA 94158
| | - Anais K. Amaya
- Department of Pediatrics, Stanford University, Stanford, CA 94305
| | | | - James A. Olzmann
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, CA 94720
- Chan Zuckerberg Biohub Network, San Francisco, CA 94158
| | - Ron R. Kopito
- Department of Biology, Stanford University, Stanford, CA 94305
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18
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McDonald EF, Oliver KE, Schlebach JP, Meiler J, Plate L. Benchmarking AlphaMissense pathogenicity predictions against cystic fibrosis variants. PLoS One 2024; 19:e0297560. [PMID: 38271453 PMCID: PMC10810519 DOI: 10.1371/journal.pone.0297560] [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: 11/03/2023] [Accepted: 01/08/2024] [Indexed: 01/27/2024] Open
Abstract
Variants in the cystic fibrosis transmembrane conductance regulator gene (CFTR) result in cystic fibrosis-a lethal autosomal recessive disorder. Missense variants that alter a single amino acid in the CFTR protein are among the most common cystic fibrosis variants, yet tools for accurately predicting molecular consequences of missense variants have been limited to date. AlphaMissense (AM) is a new technology that predicts the pathogenicity of missense variants based on dual learned protein structure and evolutionary features. Here, we evaluated the ability of AM to predict the pathogenicity of CFTR missense variants. AM predicted a high pathogenicity for CFTR residues overall, resulting in a high false positive rate and fair classification performance on CF variants from the CFTR2.org database. AM pathogenicity score correlated modestly with pathogenicity metrics from persons with CF including sweat chloride level, pancreatic insufficiency rate, and Pseudomonas aeruginosa infection rate. Correlation was also modest with CFTR trafficking and folding competency in vitro. By contrast, the AM score correlated well with CFTR channel function in vitro-demonstrating the dual structure and evolutionary training approach learns important functional information despite lacking such data during training. Different performance across metrics indicated AM may determine if polymorphisms in CFTR are recessive CF variants yet cannot differentiate mechanistic effects or the nature of pathophysiology. Finally, AM predictions offered limited utility to inform on the pharmacological response of CF variants i.e., theratype. Development of new approaches to differentiate the biochemical and pharmacological properties of CFTR variants is therefore still needed to refine the targeting of emerging precision CF therapeutics.
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Affiliation(s)
- Eli Fritz McDonald
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, United States of America
- Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Kathryn E. Oliver
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, United States of America
- Center for Cystic Fibrosis and Airways Diseases, Children’s Healthcare of Atlanta and Emory University, Atlanta, Georgia, United States of America
| | - Jonathan P. Schlebach
- Department of Chemistry, Purdue University, West Lafyette, Indiana, United States of America
| | - Jens Meiler
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, United States of America
- Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, United States of America
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
- Institute for Drug Discovery, Leipzig University, Leipzig, Germany
| | - Lars Plate
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, United States of America
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, United States of America
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
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19
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Santinelli R, Benz N, Guellec J, Quinquis F, Kocas E, Thomas J, Montier T, Ka C, Luczka-Majérus E, Sage E, Férec C, Coraux C, Trouvé P. The Inhibition of the Membrane-Bound Transcription Factor Site-1 Protease (MBTP1) Alleviates the p.Phe508del-Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) Defects in Cystic Fibrosis Cells. Cells 2024; 13:185. [PMID: 38247876 PMCID: PMC10814821 DOI: 10.3390/cells13020185] [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: 12/01/2023] [Revised: 12/27/2023] [Accepted: 01/11/2024] [Indexed: 01/23/2024] Open
Abstract
Cystic Fibrosis (CF) is present due to mutations in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene, the most frequent variant being p.phe508del. The CFTR protein is a chloride (Cl-) channel which is defective and almost absent of cell membranes when the p.Phe508del mutation is present. The p.Phe508del-CFTR protein is retained in the endoplasmic reticulum (ER) and together with inflammation and infection triggers the Unfolded Protein Response (UPR). During the UPR, the Activating Transcription Factor 6 (ATF6) is activated with cleavage and then decreases the expression of p.Phe508del-CFTR. We have previously shown that the inhibition of the activation of ATF6 alleviates the p.Phe508del-CFTR defects in cells overexpressing the mutated protein. In the present paper, our aim was to inhibit the cleavage of ATF6, and thus its activation in a human bronchial cell line with endogenous p.Phe508del-CFTR expression and in bronchial cells from patients, to be more relevant to CF. This was achieved by inhibiting the protease MBTP1 which is responsible for the cleavage of ATF6. We show here that this inhibition leads to increased mRNA and p.Phe508del-CFTR expression and, consequently, to increased Cl-efflux. We also explain the mechanisms linked to these increases with the modulation of genes when MBTP1 is inhibited. Indeed, RT-qPCR assays show that genes such as HSPA1B, CEBPB, VIMP, PFND2, MAPK8, XBP1, INSIG1, and CALR are modulated. In conclusion, we show that the inhibition of MBTP1 has a beneficial effect in relevant models to CF and that this is due to the modulation of genes involved in the disease.
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Affiliation(s)
- Raphaël Santinelli
- Univ Brest, Inserm, EFS, UMR 1078, 22 Avenue Camille Desmoulins, F-29200 Brest, France; (R.S.); (N.B.); (J.G.); (F.Q.); (E.K.); (J.T.); (T.M.); (C.K.); (C.F.)
| | - Nathalie Benz
- Univ Brest, Inserm, EFS, UMR 1078, 22 Avenue Camille Desmoulins, F-29200 Brest, France; (R.S.); (N.B.); (J.G.); (F.Q.); (E.K.); (J.T.); (T.M.); (C.K.); (C.F.)
| | - Julie Guellec
- Univ Brest, Inserm, EFS, UMR 1078, 22 Avenue Camille Desmoulins, F-29200 Brest, France; (R.S.); (N.B.); (J.G.); (F.Q.); (E.K.); (J.T.); (T.M.); (C.K.); (C.F.)
| | - Fabien Quinquis
- Univ Brest, Inserm, EFS, UMR 1078, 22 Avenue Camille Desmoulins, F-29200 Brest, France; (R.S.); (N.B.); (J.G.); (F.Q.); (E.K.); (J.T.); (T.M.); (C.K.); (C.F.)
| | - Ervin Kocas
- Univ Brest, Inserm, EFS, UMR 1078, 22 Avenue Camille Desmoulins, F-29200 Brest, France; (R.S.); (N.B.); (J.G.); (F.Q.); (E.K.); (J.T.); (T.M.); (C.K.); (C.F.)
| | - Johan Thomas
- Univ Brest, Inserm, EFS, UMR 1078, 22 Avenue Camille Desmoulins, F-29200 Brest, France; (R.S.); (N.B.); (J.G.); (F.Q.); (E.K.); (J.T.); (T.M.); (C.K.); (C.F.)
| | - Tristan Montier
- Univ Brest, Inserm, EFS, UMR 1078, 22 Avenue Camille Desmoulins, F-29200 Brest, France; (R.S.); (N.B.); (J.G.); (F.Q.); (E.K.); (J.T.); (T.M.); (C.K.); (C.F.)
| | - Chandran Ka
- Univ Brest, Inserm, EFS, UMR 1078, 22 Avenue Camille Desmoulins, F-29200 Brest, France; (R.S.); (N.B.); (J.G.); (F.Q.); (E.K.); (J.T.); (T.M.); (C.K.); (C.F.)
| | - Emilie Luczka-Majérus
- Inserm UMR-S 1250, University of Reims Champagne-Ardenne (URCA), SFR Cap-Santé, F-51100 Reims, France; (E.L.-M.); (C.C.)
| | - Edouard Sage
- Université Paris-Saclay, INRAE, UVSQ, VIM, F-78350 Jouy-en-Josas, France;
| | - Claude Férec
- Univ Brest, Inserm, EFS, UMR 1078, 22 Avenue Camille Desmoulins, F-29200 Brest, France; (R.S.); (N.B.); (J.G.); (F.Q.); (E.K.); (J.T.); (T.M.); (C.K.); (C.F.)
| | - Christelle Coraux
- Inserm UMR-S 1250, University of Reims Champagne-Ardenne (URCA), SFR Cap-Santé, F-51100 Reims, France; (E.L.-M.); (C.C.)
| | - Pascal Trouvé
- Univ Brest, Inserm, EFS, UMR 1078, 22 Avenue Camille Desmoulins, F-29200 Brest, France; (R.S.); (N.B.); (J.G.); (F.Q.); (E.K.); (J.T.); (T.M.); (C.K.); (C.F.)
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20
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Li H, Rodrat M, Al-Salmani MK, Veselu DF, Han ST, Raraigh KS, Cutting GR, Sheppard DN. Two rare variants that affect the same amino acid in CFTR have distinct responses to ivacaftor. J Physiol 2024; 602:333-354. [PMID: 38186087 PMCID: PMC10872379 DOI: 10.1113/jp285727] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 12/11/2023] [Indexed: 01/09/2024] Open
Abstract
Some residues in the cystic fibrosis transmembrane conductance regulator (CFTR) channel are the site of more than one CFTR variant that cause cystic fibrosis. Here, we investigated the function of S1159F and S1159P, two variants associated with different clinical phenotypes, which affect the same pore-lining residue in transmembrane segment 12 that are both strongly potentiated by ivacaftor when expressed in CFBE41o- bronchial epithelial cells. To study the single-channel behaviour of CFTR, we applied the patch-clamp technique to Chinese hamster ovary cells heterologously expressing CFTR variants incubated at 27°C to enhance channel residence at the plasma membrane. S1159F- and S1159P-CFTR formed Cl- channels activated by cAMP-dependent phosphorylation and gated by ATP that exhibited thermostability at 37°C. Both variants modestly reduced the single-channel conductance of CFTR. By severely attenuating channel gating, S1159F- and S1159P-CFTR reduced the open probability (Po ) of wild-type CFTR by ≥75% at ATP (1 mM); S1159F-CFTR caused the greater decrease in Po consistent with its more severe clinical phenotype. Ivacaftor (10-100 nM) doubled the Po of both CFTR variants without restoring Po values to wild-type levels, but concomitantly, ivacaftor decreased current flow through open channels. For S1159F-CFTR, the reduction of current flow was marked at high (supersaturated) ivacaftor concentrations (0.5-1 μM) and voltage-independent, identifying an additional detrimental action of elevated ivacaftor concentrations. In conclusion, S1159F and S1159P are gating variants, which also affect CFTR processing and conduction, but not stability, necessitating the use of combinations of CFTR modulators to optimally restore their channel activity. KEY POINTS: Dysfunction of the ion channel cystic fibrosis transmembrane conductance regulator (CFTR) causes the genetic disease cystic fibrosis (CF). This study investigated two rare pathogenic CFTR variants, S1159F and S1159P, which affect the same amino acid in CFTR, to understand the molecular basis of disease and response to the CFTR-targeted therapy ivacaftor. Both rare variants diminished CFTR function by modestly reducing current flow through the channel and severely inhibiting ATP-dependent channel gating with S1159F exerting the stronger adverse effect, which correlates with its association with more severe disease. Ivacaftor potentiated channel gating by both rare variants without restoring their activity to wild-type levels, but concurrently reduced current flow through open channels, particularly those of S1159F-CFTR. Our data demonstrate that S1159F and S1159P cause CFTR dysfunction by multiple mechanisms that require combinations of CFTR-targeted therapies to fully restore channel function.
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Affiliation(s)
- Hongyu Li
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - Mayuree Rodrat
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
- Center of Research and Development for Biomedical Instrumentation, Institute of Molecular Biosciences, Mahidol University, Nakhon Pathom, Thailand
| | - Majid K Al-Salmani
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
- Department of Physiology, College of Medicine and Health Sciences, Sultan Qaboos University, Al Khoudh, Muscat, Sultanate of Oman
| | | | - Sangwoo T Han
- Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Karen S Raraigh
- Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Garry R Cutting
- Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - David N Sheppard
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
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21
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Yeh HI, Sutcliffe KJ, Sheppard DN, Hwang TC. CFTR Modulators: From Mechanism to Targeted Therapeutics. Handb Exp Pharmacol 2024; 283:219-247. [PMID: 35972584 DOI: 10.1007/164_2022_597] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
People with cystic fibrosis (CF) suffer from a multi-organ disorder caused by loss-of-function variants in the gene encoding the epithelial anion channel cystic fibrosis transmembrane conductance regulator (CFTR). Tremendous progress has been made in both basic and clinical sciences over the past three decades since the identification of the CFTR gene. Over 90% of people with CF now have access to therapies targeting dysfunctional CFTR. This success was made possible by numerous studies in the field that incrementally paved the way for the development of small molecules known as CFTR modulators. The advent of CFTR modulators transformed this life-threatening illness into a treatable disease by directly binding to the CFTR protein and correcting defects induced by pathogenic variants. In this chapter, we trace the trajectory of structural and functional studies that brought CF therapies from bench to bedside, with an emphasis on mechanistic understanding of CFTR modulators.
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Affiliation(s)
- Han-I Yeh
- Department of Pharmacology, National Yang Ming Chiao Tung University, Taipei City, Taiwan
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, USA
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, USA
| | - Katy J Sutcliffe
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - David N Sheppard
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - Tzyh-Chang Hwang
- Department of Pharmacology, National Yang Ming Chiao Tung University, Taipei City, Taiwan.
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, USA.
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, USA.
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22
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Ha K, Loeb GB, Park M, Pinedo A, Park CH, Brandes N, Ritu F, Ye CJ, Reiter JF, Delling M. ADPKD-Causing Missense Variants in Polycystin-1 Disrupt Cell Surface Localization or Polycystin Channel Function. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.04.570035. [PMID: 38106161 PMCID: PMC10723288 DOI: 10.1101/2023.12.04.570035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
Autosomal dominant polycystic kidney disease (ADPKD) is the leading monogenic cause of kidney failure and affects millions of people worldwide. Despite the prevalence of this monogenic disorder, our limited mechanistic understanding of ADPKD has hindered therapeutic development. Here, we successfully developed bioassays that functionally classify missense variants in polycystin-1 (PC1). Strikingly, ADPKD pathogenic missense variants cluster into two major categories: 1) those that disrupt polycystin cell surface localization or 2) those that attenuate polycystin ion channel activity. We found that polycystin channels with defective surface localization could be rescued with a small molecule. We propose that small-molecule-based strategies to improve polycystin cell surface localization and channel function will be effective therapies for ADPKD patients.
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23
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Kamada Y, Tateishi H, Nakayamada U, Hinata D, Iwasaki A, Zhu J, Fukuda R, Okiyoneda T. UBE3C Facilitates the ER-Associated and Peripheral Degradation of Misfolded CFTR. Cells 2023; 12:2741. [PMID: 38067172 PMCID: PMC10706245 DOI: 10.3390/cells12232741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 11/24/2023] [Accepted: 11/28/2023] [Indexed: 12/18/2023] Open
Abstract
The ubiquitin E3 ligase UBE3C promotes the proteasomal degradation of cytosolic proteins and endoplasmic reticulum (ER) membrane proteins. UBE3C is proposed to function downstream of the RNF185/MBRL ER-associated degradation (ERAD) branch, contributing to the ERAD of select membrane proteins. Here, we report that UBE3C facilitates the ERAD of misfolded CFTR, even in the absence of both RNF185 and its functional ortholog RNF5 (RNF5/185). Unlike RNF5/185, UBE3C had a limited impact on the ubiquitination of misfolded CFTR. UBE3C knockdown (KD) resulted in an additional increase in the functional ∆F508-CFTR channels on the plasma membrane when combined with the RNF5/185 ablation, particularly in the presence of clinically used CFTR modulators. Interestingly, although UBE3C KD failed to attenuate the ERAD of insig-1, it reduced the ERAD of misfolded ∆Y490-ABCB1 and increased cell surface expression. UBE3C KD also stabilized the mature form of ∆F508-CFTR and increased the cell surface level of T70-CFTR, a class VI CFTR mutant. These results suggest that UBE3C plays a vital role in the ERAD of misfolded CFTR and ABCB1, even within the RNF5/185-independent ERAD pathway, and it may also be involved in maintaining the peripheral quality control of CFTR.
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Affiliation(s)
| | | | | | | | | | | | | | - Tsukasa Okiyoneda
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Hyogo 669-1330, Japan; (Y.K.); (H.T.); (U.N.); (D.H.); (A.I.); (J.Z.); (R.F.)
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24
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Riepe C, Wąchalska M, Deol KK, Amaya AK, Porteus MH, Olzmann JA, Kopito RR. Small molecule correctors divert CFTR-F508del from ERAD by stabilizing sequential folding states. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.15.556420. [PMID: 37745470 PMCID: PMC10515913 DOI: 10.1101/2023.09.15.556420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
Over 80% of people with cystic fibrosis (CF) carry the F508del mutation in the cystic fibrosis transmembrane conductance regulator (CFTR), a chloride ion channel at the apical plasma membrane (PM) of epithelial cells. F508del impairs CFTR folding causing it to be destroyed by endoplasmic reticulum associated degradation (ERAD). Small molecule correctors, which act as pharmacological chaperones to divert CFTR-F508del from ERAD, are the primary strategy for treating CF, yet corrector development continues with only a rudimentary understanding of how ERAD targets CFTR-F508del. We conducted genome-wide CRISPR/Cas9 knockout screens to systematically identify the molecular machinery that underlies CFTR-F508del ERAD. Although the ER-resident ubiquitin ligase, RNF5 was the top E3 hit, knocking out RNF5 only modestly reduced CFTR-F508del degradation. Sublibrary screens in an RNF5 knockout background identified RNF185 as a redundant ligase, demonstrating that CFTR-F508del ERAD is highly buffered. Gene-drug interaction experiments demonstrated that correctors tezacaftor (VX-661) and elexacaftor (VX-445) stabilize sequential, RNF5-resistant folding states. We propose that binding of correctors to nascent CFTR-F508del alters its folding landscape by stabilizing folding states that are not substrates for RNF5-mediated ubiquitylation.
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Affiliation(s)
- Celeste Riepe
- Department of Biology, Stanford University, Stanford, CA, USA 94305
| | - Magda Wąchalska
- Department of Biology, Stanford University, Stanford, CA, USA 94305
| | - Kirandeep K. Deol
- Department of Molecular and Cell Biology, University of California, Berkeley, CA USA 94720
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, CA USA 94720
- Chan Zuckerberg Biohub, San Francisco, CA, USA 94158
| | - Anais K. Amaya
- Department of Pediatrics, Stanford University, Stanford, CA, USA 94305
| | | | - James A. Olzmann
- Department of Molecular and Cell Biology, University of California, Berkeley, CA USA 94720
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, CA USA 94720
- Chan Zuckerberg Biohub, San Francisco, CA, USA 94158
| | - Ron R. Kopito
- Department of Biology, Stanford University, Stanford, CA, USA 94305
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25
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Brusa I, Sondo E, Pesce E, Tomati V, Gioia D, Falchi F, Balboni B, Ortega Martínez JA, Veronesi M, Romeo E, Margaroli N, Recanatini M, Girotto S, Pedemonte N, Roberti M, Cavalli A. Innovative Strategy toward Mutant CFTR Rescue in Cystic Fibrosis: Design and Synthesis of Thiadiazole Inhibitors of the E3 Ligase RNF5. J Med Chem 2023. [PMID: 37440686 PMCID: PMC10388311 DOI: 10.1021/acs.jmedchem.3c00608] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/15/2023]
Abstract
In cystic fibrosis (CF), deletion of phenylalanine 508 (F508del) in the CF transmembrane conductance regulator (CFTR) is associated to misfolding and defective gating of the mutant channel. One of the most promising CF drug targets is the ubiquitin ligase RNF5, which promotes F508del-CFTR degradation. Recently, the first ever reported inhibitor of RNF5 was discovered, i.e., the 1,2,4-thiadiazol-5-ylidene inh-2. Here, we designed and synthesized a series of new analogues to explore the structure-activity relationships (SAR) of this class of compounds. SAR efforts ultimately led to compound 16, which showed a greater F508del-CFTR corrector activity than inh-2, good tolerability, and no toxic side effects. Analogue 16 increased the basal level of autophagy similar to what has been described with RNF5 silencing. Furthermore, co-treatment with 16 significantly improved the F508del-CFTR rescue induced by the triple combination elexacaftor/tezacaftor/ivacaftor in CFBE41o- cells. These findings validate the 1,2,4-thiadiazolylidene scaffold for the discovery of novel RNF5 inhibitors and provide evidence to pursue this unprecedented strategy for the treatment of CF.
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Affiliation(s)
- Irene Brusa
- Department of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, Italy
- Computational & Chemical Biology, Istituto Italiano di Tecnologia, 16163 Genova, Italy
| | - Elvira Sondo
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, 16147 Genova, Italy
| | - Emanuela Pesce
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, 16147 Genova, Italy
| | - Valeria Tomati
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, 16147 Genova, Italy
| | - Dario Gioia
- Computational & Chemical Biology, Istituto Italiano di Tecnologia, 16163 Genova, Italy
| | - Federico Falchi
- Department of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, Italy
- Computational & Chemical Biology, Istituto Italiano di Tecnologia, 16163 Genova, Italy
| | - Beatrice Balboni
- Department of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, Italy
- Computational & Chemical Biology, Istituto Italiano di Tecnologia, 16163 Genova, Italy
| | | | - Marina Veronesi
- Structural Biophysics and Translational Pharmacology Facility, Istituto Italiano di Tecnologia, 16163 Genova, Italy
| | - Elisa Romeo
- Structural Biophysics and Translational Pharmacology Facility, Istituto Italiano di Tecnologia, 16163 Genova, Italy
| | - Natasha Margaroli
- Structural Biophysics and Translational Pharmacology Facility, Istituto Italiano di Tecnologia, 16163 Genova, Italy
| | - Maurizio Recanatini
- Department of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, Italy
| | - Stefania Girotto
- Structural Biophysics and Translational Pharmacology Facility, Istituto Italiano di Tecnologia, 16163 Genova, Italy
| | | | - Marinella Roberti
- Department of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, Italy
| | - Andrea Cavalli
- Department of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, Italy
- Computational & Chemical Biology, Istituto Italiano di Tecnologia, 16163 Genova, Italy
- Centre Européen de Calcul Atomique et Moléculaire, EPFL CECAM, 1015 Lousanne, Switzerland
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26
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Hunt WD, McCarty NA, Marin EM, Westafer RS, Yamin PR, Cui G, Eckford AW, Denison DR. A transistor model for the cystic fibrosis transmembrane conductance regulator. BIOPHYSICAL REPORTS 2023; 3:100108. [PMID: 37351179 PMCID: PMC10282560 DOI: 10.1016/j.bpr.2023.100108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 04/07/2023] [Indexed: 06/24/2023]
Abstract
In this paper we present a transistor circuit model for cystic fibrosis transmembrane conductance regulator (CFTR) that seeks to map the functional form of CFTR both in wild type and mutants. The circuit architecture is configured so that the function, and as much as possible the form, faithfully represents what is known about CFTR from cryo-electron microscopy and molecular dynamics. The model is a mixed analog-digital topology with an AND gate receiving the input from two separate ATP-nucleotide-binding domain binding events. The analog portion of the circuit takes the output from the AND gate as its input. The input to the circuit model and its noise characteristics are extracted from single-channel patch-clamp experiments. The chloride current predicted by the model is then compared with single-channel patch-clamp recordings for wild-type CFTR. We also consider the patch-clamp recordings from CFTR with a G551D point mutation, a clinically relevant mutant that is responsive to therapeutic management. Our circuit model approach enables bioengineering approaches to CFTR and allows biophysicists to use efficient circuit simulation tools to analyze its behavior.
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Affiliation(s)
| | | | | | | | | | - Guiying Cui
- Emory University School of Medicine, Atlanta, Georgia
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27
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Galles GD, Infield DT, Clark CJ, Hemshorn ML, Manikandan S, Fazan F, Rasouli A, Tajkhorshid E, Galpin JD, Cooley RB, Mehl RA, Ahern CA. Tuning phenylalanine fluorination to assess aromatic contributions to protein function and stability in cells. Nat Commun 2023; 14:59. [PMID: 36599844 PMCID: PMC9813137 DOI: 10.1038/s41467-022-35761-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 12/27/2022] [Indexed: 01/05/2023] Open
Abstract
The aromatic side-chains of phenylalanine, tyrosine, and tryptophan interact with their environments via both hydrophobic and electrostatic interactions. Determining the extent to which these contribute to protein function and stability is not possible with conventional mutagenesis. Serial fluorination of a given aromatic is a validated method in vitro and in silico to specifically alter electrostatic characteristics, but this approach is restricted to a select few experimental systems. Here, we report a group of pyrrolysine-based aminoacyl-tRNA synthetase/tRNA pairs (tRNA/RS pairs) that enable the site-specific encoding of a varied spectrum of fluorinated phenylalanine amino acids in E. coli and mammalian (HEK 293T) cells. By allowing the cross-kingdom expression of proteins bearing these unnatural amino acids at biochemical scale, these tools may potentially enable the study of biological mechanisms which utilize aromatic interactions in structural and cellular contexts.
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Affiliation(s)
- Grace D Galles
- Department of Molecular Physiology and Biophysics, University of Iowa College of Medicine, Iowa City, IA, USA
- The GCE4All Research Center, Department of Biochemistry & Biophysics, Oregon State University, Corvallis, OR, USA
| | - Daniel T Infield
- Department of Molecular Physiology and Biophysics, University of Iowa College of Medicine, Iowa City, IA, USA
| | - Colin J Clark
- Department of Molecular Physiology and Biophysics, University of Iowa College of Medicine, Iowa City, IA, USA
| | - Marcus L Hemshorn
- The GCE4All Research Center, Department of Biochemistry & Biophysics, Oregon State University, Corvallis, OR, USA
| | - Shivani Manikandan
- Department of Molecular Physiology and Biophysics, University of Iowa College of Medicine, Iowa City, IA, USA
| | - Frederico Fazan
- Department of Molecular Physiology and Biophysics, University of Iowa College of Medicine, Iowa City, IA, USA
| | - Ali Rasouli
- Theoretical and Computational Biophysics Group, NIH Center for Macromolecular Modeling and Bioinformatics, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Emad Tajkhorshid
- Theoretical and Computational Biophysics Group, NIH Center for Macromolecular Modeling and Bioinformatics, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Jason D Galpin
- Department of Molecular Physiology and Biophysics, University of Iowa College of Medicine, Iowa City, IA, USA
| | - Richard B Cooley
- The GCE4All Research Center, Department of Biochemistry & Biophysics, Oregon State University, Corvallis, OR, USA
| | - Ryan A Mehl
- The GCE4All Research Center, Department of Biochemistry & Biophysics, Oregon State University, Corvallis, OR, USA
| | - Christopher A Ahern
- Department of Molecular Physiology and Biophysics, University of Iowa College of Medicine, Iowa City, IA, USA.
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28
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Bacalhau M, Ferreira FC, Silva IAL, Buarque CD, Amaral MD, Lopes-Pacheco M. Additive Potentiation of R334W-CFTR Function by Novel Small Molecules. J Pers Med 2023; 13:jpm13010102. [PMID: 36675763 PMCID: PMC9862739 DOI: 10.3390/jpm13010102] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 12/22/2022] [Accepted: 12/23/2022] [Indexed: 01/04/2023] Open
Abstract
The R334W (c.1000C>T, p.Arg334Trp) is a rare cystic fibrosis (CF)-causing mutation for which no causal therapy is currently approved. This mutation leads to a significant reduction of CF transmembrane conductance regulator (CFTR) channel conductance that still allows for residual function. Potentiators are small molecules that interact with CFTR protein at the plasma membrane to enhance CFTR-dependent chloride secretion, representing thus pharmacotherapies targeting the root cause of the disease. Here, we generated a new CF bronchial epithelial (CFBE) cell line to screen a collection of compounds and identify novel potentiators for R334W-CFTR. The active compounds were then validated by electrophysiological assays and their additive effects in combination with VX-770, genistein, or VX-445 were exploited in this cell line and further confirmed in intestinal organoids. Four compounds (LSO-24, LSO-25, LSO-38, and LSO-77) were active in the functional primary screen and their ability to enhance R334W-CFTR-dependent chloride secretion was confirmed using electrophysiological measurements. In silico ADME analyses demonstrated that these compounds follow Lipinski’s rule of five and are thus suggested to be orally bioavailable. Dose−response relationships revealed nevertheless suboptimal efficacy and weak potency exerted by these compounds. VX-770 and genistein also displayed a small potentiation of R334W-CFTR function, while VX-445 demonstrated no potentiator activity for this mutation. In the R334W-expressing cell line, CFTR function was further enhanced by the combination of LSO-24, LSO-25, LSO-38, or LSO-77 with VX-770, but not with genistein. The efficacy of potentiator VX-770 combined with active LSO compounds was further confirmed in intestinal organoids (R334W/R334W genotype). Taken together, these molecules were demonstrated to potentiate R334W-CFTR function by a different mechanism than that of VX-770. They may provide a feasible starting point for the design of analogs with improved CFTR-potentiator activity.
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Affiliation(s)
- Mafalda Bacalhau
- Biosystems & Integrative Sciences Institute, Faculty of Sciences, University of Lisbon, 1749-016 Lisbon, Portugal
| | - Filipa C. Ferreira
- Biosystems & Integrative Sciences Institute, Faculty of Sciences, University of Lisbon, 1749-016 Lisbon, Portugal
| | - Iris A. L. Silva
- Biosystems & Integrative Sciences Institute, Faculty of Sciences, University of Lisbon, 1749-016 Lisbon, Portugal
| | - Camilla D. Buarque
- Department of Chemistry, Pontifical Catholic University of Rio de Janeiro, Rio de Janeiro 22541-041, Brazil
| | - Margarida D. Amaral
- Biosystems & Integrative Sciences Institute, Faculty of Sciences, University of Lisbon, 1749-016 Lisbon, Portugal
| | - Miquéias Lopes-Pacheco
- Biosystems & Integrative Sciences Institute, Faculty of Sciences, University of Lisbon, 1749-016 Lisbon, Portugal
- Correspondence:
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29
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Koch KC, Tew GN. Functional antibody delivery: Advances in cellular manipulation. Adv Drug Deliv Rev 2023; 192:114586. [PMID: 36280179 DOI: 10.1016/j.addr.2022.114586] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 10/10/2022] [Accepted: 10/18/2022] [Indexed: 02/03/2023]
Abstract
The current therapeutic antibody market in the U.S. consists of 100 antibody-based products and their market value is expected to explode beyond $300 billion by 2025. These therapies are presently limited to extracellular targets due to the innate inability of antibodies to transverse membranes. To expand the number of accessible therapeutic targets, intracellular antibody delivery is necessary. Many delivery vehicles for antibodies have been used with some promising results, such as nanoparticles and cell penetrating polymers. Despite the success of these delivery platforms using model antibody cargo, there is a surprisingly small number of studies that focus on functional antibody delivery into the cytosol that also measures a cellular response. Antibodies can be designed for essentially unlimited targets, including proteins and DNA, that will ultimately control cell function once delivered inside cells. Advancement in cellular manipulation depends on the application of intracellularly delivering functional antibodies to achieve a desired result. This review focuses on the emerging field of functional antibody delivery which enables various cellular responses and cell manipulation.
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Affiliation(s)
- Kayla C Koch
- Department of Polymer Science & Engineering, University of Massachusetts, Amherst, MA 01003, United States
| | - Gregory N Tew
- Department of Polymer Science & Engineering, University of Massachusetts, Amherst, MA 01003, United States; Molecular & Cellular Biology Program, University of Massachusetts, Amherst, MA 01003, United States; Department of Veterinary & Animal Sciences, University of Massachusetts, Amherst, MA 01003, United States.
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30
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Miguel L, Gervais J, Nicolas G, Lecourtois M. SorLA Protective Function Is Restored by Improving SorLA Protein Maturation in a Subset of Alzheimer's Disease-Associated SORL1 Missense Variants. J Alzheimers Dis 2023; 94:1343-1349. [PMID: 37424467 DOI: 10.3233/jad-230211] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/11/2023]
Abstract
SORL1 loss of function is associated with Alzheimer's disease (AD) risk through increased Aβ peptide secretion. We expressed 10 maturation-defective rare missense SORL1 variants in HEK cells and showed that decreasing growing temperature led to a significant increase in the maturation of the encoded protein SorLA for 6/10. In edited hiPSC carrying two of these variants, maturation of the protein was restored partially by decreasing the culture temperature and was associated with concomitant decrease in Aβ secretion. Correcting SorLA maturation in the context of maturation-defective missense variants could thus be a relevant strategy to improve SorLA protective function against AD.
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Affiliation(s)
- Laetitia Miguel
- Univ Rouen Normandie, Inserm U1245 and CHU Rouen, Department of Genetics and CNR-MAJ, F-76000 Rouen, France
| | - Juliette Gervais
- Univ Rouen Normandie, Inserm U1245 and CHU Rouen, Department of Genetics and CNR-MAJ, F-76000 Rouen, France
| | - Gaël Nicolas
- Univ Rouen Normandie, Inserm U1245 and CHU Rouen, Department of Genetics and CNR-MAJ, F-76000 Rouen, France
| | - Magalie Lecourtois
- Univ Rouen Normandie, Inserm U1245 and CHU Rouen, Department of Genetics and CNR-MAJ, F-76000 Rouen, France
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31
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Bacalhau M, Ferreira FC, Kmit A, Souza FR, da Silva VD, Pimentel AS, Amaral MD, Buarque CD, Lopes-Pacheco M. Identification of novel F508del-CFTR traffic correctors among triazole derivatives. Eur J Pharmacol 2022; 938:175396. [PMID: 36410419 DOI: 10.1016/j.ejphar.2022.175396] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 11/14/2022] [Accepted: 11/15/2022] [Indexed: 11/21/2022]
Abstract
The most prevalent cystic fibrosis (CF)-causing mutation - F508del - impairs the folding of CFTR protein, resulting in its defective trafficking and premature degradation. Small molecules termed correctors may rescue F508del-CFTR and therefore constitute promising pharmacotherapies acting on the fundamental cause of the disease. Here, we screened a collection of triazole compounds to identify novel F508del-CFTR correctors. The functional primary screen identified four hit compounds (LSO-18, LSO-24, LSO-28, and LSO-39), which were further validated and demonstrated to rescue F508del-CFTR processing, plasma membrane trafficking, and function. To interrogate their mechanism of action (MoA), we examined their additivity to the clinically approved drugs VX-661 and VX-445, low temperature, and genetic revertants of F508del-CFTR. Rescue of F508del-CFTR processing and function by LSO-18, LSO-24, and LSO-28, but not by LSO-39, was additive to VX-661, whereas LSO-28 and LSO-39, but not LSO-18 nor LSO-24, were additive to VX-445. All compounds under investigation demonstrated additive rescue of F508del-CFTR processing and function to low temperature as well as to rescue by genetic revertants G550E and 4RK. Nevertheless, none of these compounds was able to rescue processing nor function of DD/AA-CFTR, and LSO-39 (similarly to VX-661) exhibited no additivity to genetic revertant R1070W. From these findings, we suggest that LSO-39 (like VX-661) has a putative binding site at the NBD1:ICL4 interface, LSO-18 and LSO-24 seem to share the MoA with VX-445, and LSO-28 appears to act by a different MoA. Altogether, these findings represent an encouraging starting point to further exploit this chemical series for the development of novel CFTR correctors.
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Affiliation(s)
- Mafalda Bacalhau
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisbon, Lisbon, Portugal
| | - Filipa C Ferreira
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisbon, Lisbon, Portugal
| | - Arthur Kmit
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisbon, Lisbon, Portugal
| | - Felipe R Souza
- Department of Chemistry, Pontifical Catholic University of Rio de Janeiro (PUC-Rio), Rio de Janeiro, Brazil
| | - Verônica D da Silva
- Department of Chemistry, Pontifical Catholic University of Rio de Janeiro (PUC-Rio), Rio de Janeiro, Brazil
| | - André S Pimentel
- Department of Chemistry, Pontifical Catholic University of Rio de Janeiro (PUC-Rio), Rio de Janeiro, Brazil
| | - Margarida D Amaral
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisbon, Lisbon, Portugal
| | - Camilla D Buarque
- Department of Chemistry, Pontifical Catholic University of Rio de Janeiro (PUC-Rio), Rio de Janeiro, Brazil
| | - Miquéias Lopes-Pacheco
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisbon, Lisbon, Portugal.
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Miyano K, Okamoto S, Kajikawa M, Kiyohara T, Kawai C, Yamauchi A, Kuribayashi F. Regulation of Derlin-1-mediated degradation of NADPH oxidase partner p22 phox by thiol modification. Redox Biol 2022; 56:102479. [PMID: 36122532 PMCID: PMC9486109 DOI: 10.1016/j.redox.2022.102479] [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: 08/01/2022] [Revised: 09/06/2022] [Accepted: 09/12/2022] [Indexed: 11/26/2022] Open
Abstract
The transmembrane protein p22phox heterodimerizes with NADPH oxidase (Nox) 1–4 and is essential for the reactive oxygen species-producing capacity of oxidases. Missense mutations in the p22phox gene prevent the formation of phagocytic Nox2-based oxidase, which contributes to host defense. This results in chronic granulomatous disease (CGD), a severe primary immunodeficiency syndrome. In this study, we characterized missense mutations in p22phox (L51Q, L52P, E53V, and P55R) in the A22° type (wherein the p22phox protein is undetectable) of CGD. We demonstrated that these substitutions enhanced the degradation of the p22phox protein in the endoplasmic reticulum (ER) and the binding of p22phox to Derlin-1, a key component of ER-associated degradation (ERAD). Therefore, the L51-L52-E53-P55 sequence is responsible for protein stability in the ER. We observed that the oxidation of the thiol group of Cys-50, which is adjacent to the L51-L52-E53-P55 sequence, suppressed p22phox degradation. However, the suppression effect was markedly attenuated by the serine substitution of Cys-50. Blocking the free thiol of Cys-50 by alkylation or C50S substitution promoted the association of p22phox with Derlin-1. Derlin-1 depletion partially suppressed the degradation of p22phox mutant proteins. Furthermore, heterodimerization with p22phox (C50S) induced rapid degradation of not only Nox2 but also nonphagocytic Nox4 protein, which is responsible for redox signaling. Thus, the redox-sensitive Cys-50 appears to determine whether p22phox becomes a target for degradation by the ERAD system through its interaction with Derlin-1. Missense mutations in exon 3 of p22phox enhance the binding of p22phox to Derlin-1. Oxidation of the thiol group of p22phox Cys50 suppresses p22phox degradation. Serine substitution of Cys-50 increases the affinity of p22phox for Derlin-1. Stability of the p22phox protein is regulated by redox-sensitive Cys-50.
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Affiliation(s)
- Kei Miyano
- Department of Natural Sciences, Kawasaki Medical School, 577 Matsushima Kurashiki, Okayama, 701-0192, Japan; Department of Biochemistry, Kawasaki Medical School, 577 Matsushima Kurashiki, Okayama, 701-0192, Japan.
| | - Shuichiro Okamoto
- Department of Biochemistry, Kawasaki Medical School, 577 Matsushima Kurashiki, Okayama, 701-0192, Japan
| | - Mizuho Kajikawa
- Laboratory of Microbiology, Showa Pharmaceutical University, 3-3165 Higashi-Tamagawagakuen, Machida, Tokyo, 194-8543, Japan
| | - Takuya Kiyohara
- Department of Medicine and Clinical Science, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Chikage Kawai
- Department of Biochemistry, Kawasaki Medical School, 577 Matsushima Kurashiki, Okayama, 701-0192, Japan
| | - Akira Yamauchi
- Department of Biochemistry, Kawasaki Medical School, 577 Matsushima Kurashiki, Okayama, 701-0192, Japan
| | - Futoshi Kuribayashi
- Department of Biochemistry, Kawasaki Medical School, 577 Matsushima Kurashiki, Okayama, 701-0192, Japan
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33
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Amaral MD. Using the genome to correct the ion transport defect in cystic fibrosis. J Physiol 2022; 601:1573-1582. [PMID: 36068724 DOI: 10.1113/jp282308] [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: 07/04/2022] [Accepted: 08/31/2022] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS Human genome information can help finding drugs for human diseases. 'Omics' allow unbiased identification of novel drug targets. High-throughput (HT) approaches provide a global view on disease mechanisms. As a monogenic disease CF has led the way in multiple 'Omic' studies. 'Multi-omics' integration will generate maximal biological significance. ABSTRACT Today Biomedicine faces one of its greatest challenges, i.e. treating diseases through their causative dysfunctional processes and not just their symptoms. However, we still miss a global view of mechanisms and pathways involved in pathophysiology of most diseases. In fact, disease mechanisms and pathways can be achieved by holistic studies provided by 'Omic' approaches. Cystic Fibrosis (CF), caused by mutations in the CF transmembrane conductance regulator (CFTR) gene which encodes an anion channel, is paradigmatic for monogenic disorders, namely channelopathies. A high number of 'omics studies' have focussed on CF, namely several cell-based high-throughput (HT) approaches were developed and applied towards a global mechanistic characterization of CF pathophysiology and the identification of novel and 'unbiased' drug targets. Notwithstanding, it is likely that, through the integration of all these 'layers' of large datasets into comprehensive disease maps that biological significance can be extracted so that the enormous potential of these approaches to identifying dysfunctional mechanisms and novel drugs may become a reality. Abstract figure legend Schematic overview of the 3 main approaches to discovery of new drugs/drug targets. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Margarida D Amaral
- BioISI - Biosystems & Integrative Sciences Institute, Faculty of Sciences, University of Lisboa, Campo Grande-C8 bdg, Lisboa, 1749-016, Portugal
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34
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TMAO to the rescue of pathogenic protein variants. Biochim Biophys Acta Gen Subj 2022; 1866:130214. [PMID: 35902028 DOI: 10.1016/j.bbagen.2022.130214] [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: 02/03/2022] [Revised: 07/11/2022] [Accepted: 07/21/2022] [Indexed: 11/22/2022]
Abstract
Trimethylamine N-oxide (TMAO) is a chemical chaperone found in various organisms including humans. Various studies unveiled that it is an excellent protein-stabilizing agent, and induces folding of unstructured proteins. It is also well established that it can counteract the deleterious effects of urea, salt, and hydrostatic pressure on macromolecular integrity. There is also existence of large body of data regarding its ability to restore functional deficiency of various mutant proteins or pathogenic variants by correcting misfolding defects and inhibiting the formation of high-order toxic protein oligomers. Since an important class of human disease called "protein conformational disorders" is due to protein misfolding and/or formation of high-order oligomers, TMAO stands as a promising molecule for the therapeutic intervention of such diseases. The present review has been designed to gather a comprehensive knowledge of the TMAO's effect on the functional restoration of various mutants, identify its shortcomings and explore its potentiality as a lead molecule. Future prospects have also been suitably incorporated.
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35
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Hadziselimovic F, Verkauskas G, Stadler M. A novel role for CFTR interaction with LH and FGF in azoospermia and epididymal maldevelopment caused by cryptorchidism. Basic Clin Androl 2022; 32:10. [PMID: 35725394 PMCID: PMC9210799 DOI: 10.1186/s12610-022-00160-0] [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: 03/08/2022] [Accepted: 05/16/2022] [Indexed: 11/21/2022] Open
Abstract
Cryptorchidism occurs frequently in children with cystic fibrosis. Among boys with cryptorchidism and abrogated mini-puberty, the development of the epididymis and the vas deferens is frequently impaired. This finding suggests that a common cause underlies the abnormal development of Ad spermatogonia and the epididymis. The cystic fibrosis transmembrane conductance regulator (CFTR) is an ATP-binding cassette transporter protein that acts as a chloride channel. The CFTR gene has been associated with spermatogenesis and male fertility. In boys with cryptorchidism, prepubertal hypogonadotropic hypogonadism induces suboptimal expression of the ankyrin-like protein gene, ASZ1, the P-element induced wimpy testis-like gene, PIWIL, and CFTR. The abrogated expression of these gene leads to transposon reactivation, and ultimately, infertility. Curative gonadotropin-releasing hormone agonist (GnRHa) treatment stimulates the expression of CFTR and PIWIL3, which play important roles in the development of Ad spermatogonia and fertility. Furthermore, GnRHa stimulates the expression of the epididymal androgen-sensitive genes, CRISP1, WFDC8, SPINK13, and PAX2, which thereby promotes epididymal development. This review focuses on molecular evidence that favors a role for CFTR in cryptorchidism-induced infertility. Based on information available in the literature, we interpreted our RNA-Seq expression data obtained from samples before and after randomized GnRHa treatment in boys with bilateral cryptorchidism. We propose that, in boys with cryptorchidism, CFTR expression is controlled by luteinizing hormone and testosterone. Moreover, CFTR regulates the activities of genes that are important for fertility and Wolffian duct differentiation.
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Affiliation(s)
- Faruk Hadziselimovic
- Cryptorchidism Research Institute, Children's Day Care Center Liestal, 4410, Liestal, Schweiz, Switzerland.
| | - Gilvydas Verkauskas
- Children's Surgery Centre, Faculty of Medicine, Vilnius University, 01513, Vilnius, Lithuania
| | - Michael Stadler
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland.,Swiss Institute of Bioinformatics, Basel, Switzerland.,Faculty of Science, University of Basel, Basel, Switzerland
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36
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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: 17] [Impact Index Per Article: 8.5] [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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37
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Wang C, Anglès F, Balch WE. Triangulating variation in the population to define mechanisms for precision management of genetic disease. Structure 2022; 30:1190-1207.e5. [PMID: 35714602 PMCID: PMC9357173 DOI: 10.1016/j.str.2022.05.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 04/18/2022] [Accepted: 05/17/2022] [Indexed: 10/18/2022]
Abstract
To understand mechanistically how the protein fold is shaped by therapeutics to inform precision management of disease, we developed variation-capture (VarC) mapping. VarC triangulates sparse sequence variation information found in the population using Gaussian process regression (GPR)-based machine learning to define the combined pairwise-residue interactions contributing to dynamic protein function in the individual in response to therapeutics. Using VarC mapping, we now reveal the pairwise-residue covariant relationships across the entire protein fold of cystic fibrosis (CF) transmembrane conductance regulator (CFTR) to define the molecular mechanisms of clinically approved CF chemical modulators. We discover an energetically destabilized covariant core containing a di-acidic YKDAD endoplasmic reticulum (ER) exit code that is only weakly corrected by current therapeutics. Our results illustrate that VarC provides a generalizable tool to triangulate information from genetic variation in the population to mechanistically discover therapeutic strategies that guide precision management of the individual.
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Affiliation(s)
- Chao Wang
- Department of Molecular Medicine, Scripps Research, La Jolla, CA 92037, USA
| | - Frédéric Anglès
- Department of Molecular Medicine, Scripps Research, La Jolla, CA 92037, USA
| | - William E Balch
- Department of Molecular Medicine, Scripps Research, La Jolla, CA 92037, USA.
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38
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Anglès F, Wang C, Balch WE. Spatial covariance analysis reveals the residue-by-residue thermodynamic contribution of variation to the CFTR fold. Commun Biol 2022; 5:356. [PMID: 35418593 PMCID: PMC9008016 DOI: 10.1038/s42003-022-03302-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 03/21/2022] [Indexed: 12/21/2022] Open
Abstract
Although the impact of genome variation on the thermodynamic properties of function on the protein fold has been studied in vitro, it remains a challenge to assign these relationships across the entire polypeptide sequence in vivo. Using the Gaussian process regression based principle of Spatial CoVariance, we globally assign on a residue-by-residue basis the biological thermodynamic properties that contribute to the functional fold of CFTR in the cell. We demonstrate the existence of a thermodynamically sensitive region of the CFTR fold involving the interface between NBD1 and ICL4 that contributes to its export from endoplasmic reticulum. At the cell surface a new set of residues contribute uniquely to the management of channel function. These results support a general 'quality assurance' view of global protein fold management as an SCV principle describing the differential pre- and post-ER residue interactions contributing to compartmentalization of the energetics of the protein fold for function. Our results set the stage for future analyses of the quality systems managing protein sequence-to-function-to-structure broadly encompassing genome design leading to protein function in complex cellular relationships responsible for diversity and fitness in biology in response to the environment.
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Affiliation(s)
- Frédéric Anglès
- Scripps Research, Department of Molecular Medicine, 10550 North Torrey Pines Rd, La Jolla, CA, 92037, USA
| | - Chao Wang
- Scripps Research, Department of Molecular Medicine, 10550 North Torrey Pines Rd, La Jolla, CA, 92037, USA
| | - William E Balch
- Scripps Research, Department of Molecular Medicine, 10550 North Torrey Pines Rd, La Jolla, CA, 92037, USA.
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39
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McDonald EF, Woods H, Smith ST, Kim M, Schoeder CT, Plate L, Meiler J. Structural Comparative Modeling of Multi-Domain F508del CFTR. Biomolecules 2022; 12:biom12030471. [PMID: 35327663 PMCID: PMC8946492 DOI: 10.3390/biom12030471] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 03/15/2022] [Accepted: 03/17/2022] [Indexed: 12/07/2022] Open
Abstract
Cystic fibrosis (CF) is a rare genetic disease caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR), an epithelial anion channel expressed in several vital organs. Absence of functional CFTR results in imbalanced osmotic equilibrium and subsequent mucus build up in the lungs-which increases the risk of infection and eventually causes death. CFTR is an ATP-binding cassette (ABC) transporter family protein composed of two transmembrane domains (TMDs), two nucleotide binding domains (NBDs), and an unstructured regulatory domain. The most prevalent patient mutation is the deletion of F508 (F508del), making F508del CFTR the primary target for current FDA approved CF therapies. However, no experimental multi-domain F508del CFTR structure has been determined and few studies have modeled F508del using multi-domain WT CFTR structures. Here, we used cryo-EM density data and Rosetta comparative modeling (RosettaCM) to compare a F508del model with published experimental data on CFTR NBD1 thermodynamics. We then apply this modeling method to generate multi-domain WT and F508del CFTR structural models. These models demonstrate the destabilizing effects of F508del on NBD1 and the NBD1/TMD interface in both the inactive and active conformation of CFTR. Furthermore, we modeled F508del/R1070W and F508del bound to the CFTR corrector VX-809. Our models reveal the stabilizing effects of VX-809 on multi-domain models of F508del CFTR and pave the way for rational design of additional drugs that target F508del CFTR for treatment of CF.
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Affiliation(s)
- Eli Fritz McDonald
- Department of Chemistry, Vanderbilt University, Nashville, TN 37235, USA; (E.F.M.); (C.T.S.); (L.P.)
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37235, USA; (H.W.); (S.T.S.)
| | - Hope Woods
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37235, USA; (H.W.); (S.T.S.)
- Program in Chemical and Physical Biology, Vanderbilt University, Nashville, TN 37235, USA;
| | - Shannon T. Smith
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37235, USA; (H.W.); (S.T.S.)
- Program in Chemical and Physical Biology, Vanderbilt University, Nashville, TN 37235, USA;
| | - Minsoo Kim
- Program in Chemical and Physical Biology, Vanderbilt University, Nashville, TN 37235, USA;
| | - Clara T. Schoeder
- Department of Chemistry, Vanderbilt University, Nashville, TN 37235, USA; (E.F.M.); (C.T.S.); (L.P.)
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37235, USA; (H.W.); (S.T.S.)
- Leipzig Medical School, Leipzig University, 04109 Leipzig, Germany
| | - Lars Plate
- Department of Chemistry, Vanderbilt University, Nashville, TN 37235, USA; (E.F.M.); (C.T.S.); (L.P.)
- Department of Biological Sciences, Vanderbilt University, Nashville, TN 37235, USA
| | - Jens Meiler
- Department of Chemistry, Vanderbilt University, Nashville, TN 37235, USA; (E.F.M.); (C.T.S.); (L.P.)
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37235, USA; (H.W.); (S.T.S.)
- Leipzig Medical School, Leipzig University, 04109 Leipzig, Germany
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37235, USA
- Institute for Drug Discovery, Leipzig University, 04109 Leipzig, Germany
- Correspondence: ; Tel.: +1-(615)-936-2211
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40
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Carlile GW, Yang Q, Matthes E, Liao J, Birault V, Sneddon HF, Poole DL, Hall CJ, Hanrahan JW, Thomas DY. The NSAID glafenine rescues class 2 CFTR mutants via cyclooxygenase 2 inhibition of the arachidonic acid pathway. Sci Rep 2022; 12:4595. [PMID: 35302062 PMCID: PMC8930988 DOI: 10.1038/s41598-022-08661-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 03/09/2022] [Indexed: 12/12/2022] Open
Abstract
Most cases of cystic fibrosis (CF) are caused by class 2 mutations in the cystic fibrosis transmembrane regulator (CFTR). These proteins preserve some channel function but are retained in the endoplasmic reticulum (ER). Partial rescue of the most common CFTR class 2 mutant, F508del-CFTR, has been achieved through the development of pharmacological chaperones (Tezacaftor and Elexacaftor) that bind CFTR directly. However, it is not clear whether these drugs will rescue all class 2 CFTR mutants to a medically relevant level. We have previously shown that the nonsteroidal anti-inflammatory drug (NSAID) ibuprofen can correct F508del-CFTR trafficking. Here, we utilized RNAi and pharmacological inhibitors to determine the mechanism of action of the NSAID glafenine. Using cellular thermal stability assays (CETSAs), we show that it is a proteostasis modulator. Using medicinal chemistry, we identified a derivative with a fourfold increase in CFTR corrector potency. Furthermore, we show that these novel arachidonic acid pathway inhibitors can rescue difficult-to-correct class 2 mutants, such as G85E-CFTR > 13%, that of non-CF cells in well-differentiated HBE cells. Thus, the results suggest that targeting the arachidonic acid pathway may be a profitable way of developing correctors of certain previously hard-to-correct class 2 CFTR mutations.
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Affiliation(s)
- Graeme W Carlile
- Department of Biochemistry, Cystic Fibrosis Translational Research Centre, McGill University, McIntyre Medical Sciences Building, 3655 Promenade Sir William Osler, Montreal, QC, H3G 1Y6, Canada.
- Department of Human Genetics, Cystic Fibrosis Translational Research Centre, McGill University, Montreal, QC, H3G 1Y6, Canada.
| | - Qi Yang
- Department of Biochemistry, Cystic Fibrosis Translational Research Centre, McGill University, McIntyre Medical Sciences Building, 3655 Promenade Sir William Osler, Montreal, QC, H3G 1Y6, Canada
- Department of Human Genetics, Cystic Fibrosis Translational Research Centre, McGill University, Montreal, QC, H3G 1Y6, Canada
| | - Elizabeth Matthes
- Department of Physiology, McGill Cystic Fibrosis Translational Research Centre, McGill University, Montreal, QC, H3G 1Y6, Canada
| | - Jie Liao
- Department of Physiology, McGill Cystic Fibrosis Translational Research Centre, McGill University, Montreal, QC, H3G 1Y6, Canada
| | - Véronique Birault
- Translation Department, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Helen F Sneddon
- Department of Chemistry, Green Chemistry Centre of Excellence, University of York, Heslington, York, YO10 5DD, UK
| | - Darren L Poole
- Medicinal Chemistry, GlaxoSmithKline, Gunnels Wood Road, Stevenage, SG1 2NY, UK
| | - Callum J Hall
- Medicinal Chemistry, GlaxoSmithKline, Gunnels Wood Road, Stevenage, SG1 2NY, UK
| | - John W Hanrahan
- Department of Physiology, McGill Cystic Fibrosis Translational Research Centre, McGill University, Montreal, QC, H3G 1Y6, Canada
| | - David Y Thomas
- Department of Biochemistry, Cystic Fibrosis Translational Research Centre, McGill University, McIntyre Medical Sciences Building, 3655 Promenade Sir William Osler, Montreal, QC, H3G 1Y6, Canada
- Department of Human Genetics, Cystic Fibrosis Translational Research Centre, McGill University, Montreal, QC, H3G 1Y6, Canada
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41
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Prins S, Corradi V, Sheppard DN, Tieleman DP, Vergani P. Can two wrongs make a right? F508del-CFTR ion channel rescue by second-site mutations in its transmembrane domains. J Biol Chem 2022; 298:101615. [PMID: 35065958 PMCID: PMC8861112 DOI: 10.1016/j.jbc.2022.101615] [Citation(s) in RCA: 4] [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: 09/01/2021] [Revised: 01/13/2022] [Accepted: 01/17/2022] [Indexed: 11/20/2022] Open
Abstract
Deletion of phenylalanine 508 (F508del) in the cystic fibrosis transmembrane conductance regulator (CFTR) anion channel is the most common cause of cystic fibrosis. The F508 residue is located on nucleotide-binding domain 1 (NBD1) in contact with the cytosolic extensions of the transmembrane helices, in particular intracellular loop 4 (ICL4). To investigate how absence of F508 at this interface impacts the CFTR protein, we carried out a mutagenesis scan of ICL4 by introducing second-site mutations at 11 positions in cis with F508del. Using an image-based fluorescence assay, we measured how each mutation affected membrane proximity and ion-channel function. The scan strongly validated the effectiveness of R1070W at rescuing F508del defects. Molecular dynamics simulations highlighted two features characterizing the ICL4/NBD1 interface of F508del/R1070W-CFTR: flexibility, with frequent transient formation of interdomain hydrogen bonds, and loosely stacked aromatic sidechains (F1068, R1070W, and F1074, mimicking F1068, F508, and F1074 in WT CFTR). F508del-CFTR displayed a distorted aromatic stack, with F1068 displaced toward the space vacated by F508, while in F508del/R1070F-CFTR, which largely retained F508del defects, R1070F could not form hydrogen bonds and the interface was less flexible. Other ICL4 second-site mutations which partially rescued F508del-CFTR included F1068M and F1074M. Methionine side chains allow hydrophobic interactions without the steric rigidity of aromatic rings, possibly conferring flexibility to accommodate the absence of F508 and retain a dynamic interface. These studies highlight how both hydrophobic interactions and conformational flexibility might be important at the ICL4/NBD1 interface, suggesting possible structural underpinnings of F508del-induced dysfunction.
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Affiliation(s)
- Stella Prins
- Department of Neuroscience, Physiology and Pharmacology, University College London, London, UK
| | - Valentina Corradi
- Department of Biological Sciences, Centre for Molecular Simulation, University of Calgary, Calgary, Alberta, Canada
| | - David N Sheppard
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - D Peter Tieleman
- Department of Biological Sciences, Centre for Molecular Simulation, University of Calgary, Calgary, Alberta, Canada
| | - Paola Vergani
- Department of Neuroscience, Physiology and Pharmacology, University College London, London, UK.
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42
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Lim SH, Snider J, Birimberg‐Schwartz L, Ip W, Serralha JC, Botelho HM, Lopes‐Pacheco M, Pinto MC, Moutaoufik MT, Zilocchi M, Laselva O, Esmaeili M, Kotlyar M, Lyakisheva A, Tang P, López Vázquez L, Akula I, Aboualizadeh F, Wong V, Grozavu I, Opacak‐Bernardi T, Yao Z, Mendoza M, Babu M, Jurisica I, Gonska T, Bear CE, Amaral MD, Stagljar I. CFTR interactome mapping using the mammalian membrane two-hybrid high-throughput screening system. Mol Syst Biol 2022; 18:e10629. [PMID: 35156780 PMCID: PMC8842165 DOI: 10.15252/msb.202110629] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 01/16/2022] [Accepted: 01/19/2022] [Indexed: 12/19/2022] Open
Abstract
Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) is a chloride and bicarbonate channel in secretory epithelia with a critical role in maintaining fluid homeostasis. Mutations in CFTR are associated with Cystic Fibrosis (CF), the most common lethal autosomal recessive disorder in Caucasians. While remarkable treatment advances have been made recently in the form of modulator drugs directly rescuing CFTR dysfunction, there is still considerable scope for improvement of therapeutic effectiveness. Here, we report the application of a high-throughput screening variant of the Mammalian Membrane Two-Hybrid (MaMTH-HTS) to map the protein-protein interactions of wild-type (wt) and mutant CFTR (F508del), in an effort to better understand CF cellular effects and identify new drug targets for patient-specific treatments. Combined with functional validation in multiple disease models, we have uncovered candidate proteins with potential roles in CFTR function/CF pathophysiology, including Fibrinogen Like 2 (FGL2), which we demonstrate in patient-derived intestinal organoids has a significant effect on CFTR functional expression.
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Affiliation(s)
- Sang Hyun Lim
- Donnelly CentreUniversity of TorontoTorontoONCanada
- Department of BiochemistryUniversity of TorontoTorontoONCanada
| | - Jamie Snider
- Donnelly CentreUniversity of TorontoTorontoONCanada
| | - Liron Birimberg‐Schwartz
- Programme in Translational MedicineThe Hospital for Sick ChildrenTorontoONCanada
- Division of Gastroenterology, Hepatology and NutritionDepartment of PediatricsUniversity of TorontoTorontoONCanada
| | - Wan Ip
- Programme in Translational MedicineThe Hospital for Sick ChildrenTorontoONCanada
| | - Joana C Serralha
- Faculty of SciencesBioISI‐Biosystems and Integrative Sciences InstituteUniversity of LisboaLisboaPortugal
- Faculty of Life Sciences and MedicineSchool of Bioscience EducationKing’s College LondonLondonUK
| | - Hugo M Botelho
- Faculty of SciencesBioISI‐Biosystems and Integrative Sciences InstituteUniversity of LisboaLisboaPortugal
| | - Miquéias Lopes‐Pacheco
- Faculty of SciencesBioISI‐Biosystems and Integrative Sciences InstituteUniversity of LisboaLisboaPortugal
| | - Madalena C Pinto
- Faculty of SciencesBioISI‐Biosystems and Integrative Sciences InstituteUniversity of LisboaLisboaPortugal
| | - Mohamed Taha Moutaoufik
- Department of Biochemistry, Research and Innovation CentreUniversity of ReginaReginaSKCanada
| | - Mara Zilocchi
- Department of Biochemistry, Research and Innovation CentreUniversity of ReginaReginaSKCanada
| | - Onofrio Laselva
- Department of PhysiologyUniversity of TorontoTorontoONCanada
| | - Mohsen Esmaeili
- Program in Genetics and Genome BiologyThe Hospital for Sick ChildrenTorontoONCanada
| | - Max Kotlyar
- Osteoarthritis Research ProgramDivision of Orthopedic SurgerySchroeder Arthritis InstituteUniversity Health NetworkTorontoONCanada
- Data Science Discovery Centre for Chronic DiseasesKrembil Research InstituteUniversity Health NetworkTorontoONCanada
| | | | | | | | - Indira Akula
- Donnelly CentreUniversity of TorontoTorontoONCanada
| | | | | | - Ingrid Grozavu
- Donnelly CentreUniversity of TorontoTorontoONCanada
- Department of BiochemistryUniversity of TorontoTorontoONCanada
| | | | - Zhong Yao
- Donnelly CentreUniversity of TorontoTorontoONCanada
| | - Meg Mendoza
- Department of Molecular GeneticsUniversity of TorontoTorontoONCanada
| | - Mohan Babu
- Department of Biochemistry, Research and Innovation CentreUniversity of ReginaReginaSKCanada
| | - Igor Jurisica
- Osteoarthritis Research ProgramDivision of Orthopedic SurgerySchroeder Arthritis InstituteUniversity Health NetworkTorontoONCanada
- Data Science Discovery Centre for Chronic DiseasesKrembil Research InstituteUniversity Health NetworkTorontoONCanada
- Departments of Medical Biophysics and Computer ScienceUniversity of TorontoTorontoONCanada
- Institute of NeuroimmunologySlovak Academy of SciencesBratislavaSlovakia
| | - Tanja Gonska
- Programme in Translational MedicineThe Hospital for Sick ChildrenTorontoONCanada
- Division of Gastroenterology, Hepatology and NutritionDepartment of PediatricsUniversity of TorontoTorontoONCanada
| | - Christine E Bear
- Department of BiochemistryUniversity of TorontoTorontoONCanada
- Department of PhysiologyUniversity of TorontoTorontoONCanada
| | - Margarida D Amaral
- Faculty of SciencesBioISI‐Biosystems and Integrative Sciences InstituteUniversity of LisboaLisboaPortugal
| | - Igor Stagljar
- Donnelly CentreUniversity of TorontoTorontoONCanada
- Department of BiochemistryUniversity of TorontoTorontoONCanada
- Department of Molecular GeneticsUniversity of TorontoTorontoONCanada
- Mediterranean Institute for Life SciencesSplitCroatia
- School of MedicineUniversity of SplitSplitCroatia
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Rescue of Mutant CFTR Trafficking Defect by the Investigational Compound MCG1516A. Cells 2022; 11:cells11010136. [PMID: 35011698 PMCID: PMC8750248 DOI: 10.3390/cells11010136] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2021] [Revised: 12/20/2021] [Accepted: 12/22/2021] [Indexed: 01/27/2023] Open
Abstract
Although some therapeutic progress has been achieved in developing small molecules that correct F508del-CFTR defects, the mechanism of action (MoA) of these compounds remain poorly elucidated. Here, we investigated the effects and MoA of MCG1516A, a newly developed F508del-CFTR corrector. MCG1516A effects on wild-type (WT) and F508del-CFTR were assessed by immunofluorescence microscopy, and biochemical and functional assays both in cell lines and in intestinal organoids. To shed light on the MoA of MCG1516A, we evaluated its additivity to the FDA-approved corrector VX-661, low temperature, genetic revertants of F508del-CFTR (G550E, R1070W, and 4RK), and the traffic-null variant DD/AA. Finally, we explored the ability of MCG1516A to rescue trafficking and function of other CF-causing mutations. We found that MCG1516A rescues F508del-CFTR with additive effects to VX-661. A similar behavior was observed for WT-CFTR. Under low temperature incubation, F508del-CFTR demonstrated an additivity in processing and function with VX-661, but not with MCG1516A. In contrast, both compounds promoted additional effects to low temperature to WT-CFTR. MCG1516A demonstrated additivity to genetic revertant R1070W, while VX-661 was additive to G550E and 4RK. Nevertheless, none of these compounds rescued DD/AA trafficking. Both MCG1516A and VX-661 rescued CFTR processing of L206W- and R334W-CFTR with greater effects when these compounds were combined. In summary, the absence of additivity of MCG1516A to genetic revertant G550E suggests a putative binding site for this compound on NBD1:NBD2 interface. Therefore, a combination of MCG1516A with compounds able to rescue DD/AA traffic, or mimicking the actions of revertant R1070W (e.g., VX-661), could enhance correction of F508del-CFTR defects.
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Ulloa-Aguirre A, Zariñán T, Gutiérrez-Sagal R, Tao YX. Targeting trafficking as a therapeutic avenue for misfolded GPCRs leading to endocrine diseases. Front Endocrinol (Lausanne) 2022; 13:934685. [PMID: 36093106 PMCID: PMC9452723 DOI: 10.3389/fendo.2022.934685] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 07/13/2022] [Indexed: 02/05/2023] Open
Abstract
G protein-coupled receptors (GPCRs) are plasma membrane proteins associated with an array of functions. Mutations in these receptors lead to a number of genetic diseases, including diseases involving the endocrine system. A particular subset of loss-of-function mutant GPCRs are misfolded receptors unable to traffic to their site of function (i.e. the cell surface plasma membrane). Endocrine disorders in humans caused by GPCR misfolding include, among others, hypo- and hyper-gonadotropic hypogonadism, morbid obesity, familial hypocalciuric hypercalcemia and neonatal severe hyperparathyroidism, X-linked nephrogenic diabetes insipidus, congenital hypothyroidism, and familial glucocorticoid resistance. Several in vitro and in vivo experimental approaches have been employed to restore function of some misfolded GPCRs linked to endocrine disfunction. The most promising approach is by employing pharmacological chaperones or pharmacoperones, which assist abnormally and incompletely folded proteins to refold correctly and adopt a more stable configuration to pass the scrutiny of the cell's quality control system, thereby correcting misrouting. This review covers the most important aspects that regulate folding and traffic of newly synthesized proteins, as well as the experimental approaches targeted to overcome protein misfolding, with special focus on GPCRs involved in endocrine diseases.
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Affiliation(s)
- Alfredo Ulloa-Aguirre
- Red de Apoyo a la Investigación (RAI), National University of Mexico and Instituto Nacional de Ciencias Médicas y Nutrición SZ, Mexico City, Mexico
- *Correspondence: Alfredo Ulloa-Aguirre,
| | - Teresa Zariñán
- Red de Apoyo a la Investigación (RAI), National University of Mexico and Instituto Nacional de Ciencias Médicas y Nutrición SZ, Mexico City, Mexico
| | - Rubén Gutiérrez-Sagal
- Red de Apoyo a la Investigación (RAI), National University of Mexico and Instituto Nacional de Ciencias Médicas y Nutrición SZ, Mexico City, Mexico
| | - Ya-Xiong Tao
- Department of Anatomy, Physiology & Pharmacology, Auburn University College of Veterinary Medicine, Auburn, AL, United States
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45
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Esc peptides as novel potentiators of defective cystic fibrosis transmembrane conductance regulator: an unprecedented property of antimicrobial peptides. Cell Mol Life Sci 2021; 79:67. [PMID: 34971429 PMCID: PMC8752549 DOI: 10.1007/s00018-021-04030-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 11/04/2021] [Accepted: 11/09/2021] [Indexed: 12/17/2022]
Abstract
Mutations in the cystic fibrosis (CF) transmembrane conductance regulator (CFTR) protein lead to persistent lung bacterial infections, mainly due to Pseudomonas aeruginosa, causing loss of respiratory function and finally death of people affected by CF. Unfortunately, even in the era of CFTR modulation therapies, management of pulmonary infections in CF remains highly challenging especially for patients with advanced stages of lung disease. Recently, we identified antimicrobial peptides (AMPs), namely Esc peptides, with potent antipseudomonal activity. In this study, by means of electrophysiological techniques and computational studies we discovered their ability to increase the CFTR-controlled ion currents, by direct interaction with the F508del-CFTR mutant. Remarkably, this property was not explored previously with any AMPs or peptides in general. More interestingly, in contrast with clinically used CFTR modulators, Esc peptides would give particular benefit to CF patients by combining their capability to eradicate lung infections and to act as promoters of airway wound repair with their ability to ameliorate the activity of the channel with conductance defects. Overall, our findings not only highlighted Esc peptides as the first characterized AMPs with a novel property, that is the potentiator activity of CFTR, but also paved the avenue to investigate the functions of AMPs and/or other peptide molecules, for a new up-and-coming pharmacological approach to address CF lung disease.
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46
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Farinha CM, Gentzsch M. Revisiting CFTR Interactions: Old Partners and New Players. Int J Mol Sci 2021; 22:13196. [PMID: 34947992 PMCID: PMC8703571 DOI: 10.3390/ijms222413196] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 12/02/2021] [Accepted: 12/03/2021] [Indexed: 01/07/2023] Open
Abstract
Remarkable progress in CFTR research has led to the therapeutic development of modulators that rescue the basic defect in cystic fibrosis. There is continuous interest in studying CFTR molecular disease mechanisms as not all cystic fibrosis patients have a therapeutic option available. Addressing the basis of the problem by comprehensively understanding the critical molecular associations of CFTR interactions remains key. With the availability of CFTR modulators, there is interest in comprehending which interactions are critical to rescue CFTR and which are altered by modulators or CFTR mutations. Here, the current knowledge on interactions that govern CFTR folding, processing, and stability is summarized. Furthermore, we describe protein complexes and signal pathways that modulate the CFTR function. Primary epithelial cells display a spatial control of the CFTR interactions and have become a common system for preclinical and personalized medicine studies. Strikingly, the novel roles of CFTR in development and differentiation have been recently uncovered and it has been revealed that specific CFTR gene interactions also play an important role in transcriptional regulation. For a comprehensive understanding of the molecular environment of CFTR, it is important to consider CFTR mutation-dependent interactions as well as factors affecting the CFTR interactome on the cell type, tissue-specific, and transcriptional levels.
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Affiliation(s)
- Carlos M. Farinha
- BioISI—Biosystems and Integrative Sciences Institute, Faculty of Sciences, University of Lisboa, 1749-016 Lisboa, Portugal
| | - Martina Gentzsch
- Marsico Lung Institute and Cystic Fibrosis Research Center, School of Medicine, University of North Carolina, Chapel Hill, NC 27599, USA
- Department of Pediatrics, Division of Pediatric Pulmonology, School of Medicine, University of North Carolina, Chapel Hill, NC 27599, USA
- Department of Cell Biology and Physiology, School of Medicine, University of North Carolina, Chapel Hill, NC 27599, USA
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47
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Liu M, Zaman R, Sawczak V, Periasamy A, Sun F, Zaman K. S-nitrosothiols signaling in cystic fibrosis airways. J Biosci 2021. [DOI: 10.1007/s12038-021-00223-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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48
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McKee AG, Kuntz CP, Ortega JT, Woods H, Most V, Roushar FJ, Meiler J, Jastrzebska B, Schlebach JP. Systematic Profiling of Temperature- and Retinal-Sensitive Rhodopsin Variants by Deep Mutational Scanning. J Biol Chem 2021; 297:101359. [PMID: 34756884 PMCID: PMC8649220 DOI: 10.1016/j.jbc.2021.101359] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 10/20/2021] [Accepted: 10/26/2021] [Indexed: 01/29/2023] Open
Abstract
Membrane protein variants with diminished conformational stability often exhibit enhanced cellular expression at reduced growth temperatures. The expression of “temperature-sensitive” variants is also typically sensitive to corrector molecules that bind and stabilize the native conformation. There are many examples of temperature-sensitive rhodopsin variants, the misfolding of which is associated with the molecular basis of retinitis pigmentosa. In this work, we employ deep mutational scanning to compare the effects of reduced growth temperature and 9-cis-retinal, an investigational corrector, on the plasma membrane expression of 700 rhodopsin variants in HEK293T cells. We find that the change in expression at reduced growth temperatures correlates with the response to 9-cis-retinal among variants bearing mutations within a hydrophobic transmembrane domain (TM2). The most sensitive variants appear to disrupt a native helical kink within this transmembrane domain. By comparison, mutants that alter the structure of a polar transmembrane domain (TM7) exhibit weaker responses to temperature and retinal that are poorly correlated. Statistical analyses suggest that this observed insensitivity cannot be attributed to a single variable, but likely arises from the composite effects of mutations on the energetics of membrane integration, the stability of the native conformation, and the integrity of the retinal-binding pocket. Finally, we show that the characteristics of purified temperature- and retinal-sensitive variants suggest that the proteostatic effects of retinal may be manifested during translation and cotranslational folding. Together, our findings highlight several biophysical constraints that appear to influence the sensitivity of genetic variants to temperature and small-molecule correctors.
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Affiliation(s)
- Andrew G McKee
- Department of Chemistry, Indiana University, Bloomington, Indiana, USA
| | - Charles P Kuntz
- Department of Chemistry, Indiana University, Bloomington, Indiana, USA
| | - Joseph T Ortega
- Department of Pharmacology, Case Western Reserve University, Cleveland, Ohio, USA
| | - Hope Woods
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, USA; Chemical and Physical Biology Program, Vanderbilt University, Nashville, Tennessee, USA
| | - Victoria Most
- Institute for Drug Development, Leipzig University, Leipzig, SAC, Germany
| | - Francis J Roushar
- Department of Chemistry, Indiana University, Bloomington, Indiana, USA
| | - Jens Meiler
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, USA; Institute for Drug Development, Leipzig University, Leipzig, SAC, Germany
| | - Beata Jastrzebska
- Department of Pharmacology, Case Western Reserve University, Cleveland, Ohio, USA
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49
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Liu J, Berg AP, Wang Y, Jantarajit W, Sutcliffe KJ, Stevens EB, Cao L, Pregel MJ, Sheppard DN. A small molecule CFTR potentiator restores ATP-dependent channel gating to the cystic fibrosis mutant G551D-CFTR. Br J Pharmacol 2021; 179:1319-1337. [PMID: 34644413 PMCID: PMC9304199 DOI: 10.1111/bph.15709] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Accepted: 08/30/2021] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND AND PURPOSE Cystic fibrosis transmembrane conductance regulator (CFTR) potentiators are small molecules developed to treat the genetic disease cystic fibrosis (CF). They interact directly with CFTR Cl- channels at the plasma membrane to enhance channel gating. Here, we investigate the action of a new CFTR potentiator, CP-628006 with a distinct chemical structure. EXPERIMENTAL APPROACH Using electrophysiological assays with CFTR-expressing heterologous cells and CF patient-derived human bronchial epithelial (hBE) cells, we compared the effects of CP-628006 with the marketed CFTR potentiator ivacaftor. KEY RESULTS CP-628006 efficaciously potentiated CFTR function in epithelia from cultured hBE cells. Its effects on the predominant CFTR variant F508del-CFTR were larger than those with the gating variant G551D-CFTR. In excised inside-out membrane patches, CP-628006 potentiated wild-type, F508del- and G551D-CFTR by increasing the frequency and duration of channel openings. CP-628006 increased the affinity and efficacy of F508del-CFTR gating by ATP. In these respects, CP-628006 behaved like ivacaftor. CP-628006 also demonstrated notable differences with ivacaftor. Its potency and efficacy were lower than those of ivacaftor. CP-628006 conferred ATP-dependent gating on G551D-CFTR, whereas the action of ivacaftor was ATP-independent. For G551D-CFTR, but not F508del-CFTR, the action of CP-628006 plus ivacaftor was greater than ivacaftor alone. CP-628006 delayed, but did not prevent, the deactivation of F508del-CFTR at the plasma membrane, whereas ivacaftor accentuated F508del-CFTR deactivation. CONCLUSIONS AND IMPLICATIONS CP-628006 has distinct effects compared to ivacaftor, suggesting a different mechanism of CFTR potentiation. The emergence of CFTR potentiators with diverse modes of action makes therapy with combinations of potentiators a possibility.
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Affiliation(s)
- Jia Liu
- Neuroscience and Pain Research Unit, Pfizer Inc., Granta Park, Great Abington, Cambridge, UK.,School of Physiology, Pharmacology and Neuroscience, University of Bristol, Biomedical Sciences Building, University Walk, Bristol, UK
| | - Allison P Berg
- Rare Disease Research Unit, Pfizer Inc., Cambridge, MA, USA
| | - Yiting Wang
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Biomedical Sciences Building, University Walk, Bristol, UK
| | - Walailak Jantarajit
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Biomedical Sciences Building, University Walk, Bristol, UK.,Center of Calcium and Bone Research and Department of Physiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Katy J Sutcliffe
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Biomedical Sciences Building, University Walk, Bristol, UK
| | - Edward B Stevens
- Neuroscience and Pain Research Unit, Pfizer Inc., Granta Park, Great Abington, Cambridge, UK
| | - Lishuang Cao
- Neuroscience and Pain Research Unit, Pfizer Inc., Granta Park, Great Abington, Cambridge, UK
| | - Marko J Pregel
- Rare Disease Research Unit, Pfizer Inc., Cambridge, MA, USA
| | - David N Sheppard
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Biomedical Sciences Building, University Walk, Bristol, UK
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50
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NBD2 Is Required for the Rescue of Mutant F508del CFTR by a Thiazole-Based Molecule: A Class II Corrector for the Multi-Drug Therapy of Cystic Fibrosis. Biomolecules 2021; 11:biom11101417. [PMID: 34680050 PMCID: PMC8533355 DOI: 10.3390/biom11101417] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 09/14/2021] [Accepted: 09/21/2021] [Indexed: 11/17/2022] Open
Abstract
Cystic fibrosis (CF) is caused by loss-of-function mutations in the CF transmembrane conductance regulator (CFTR) protein, an anion channel that regulates epithelial surface fluid secretion. The deletion of phenylalanine at position 508 (F508del) is the most common CFTR mutation. F508del CFTR is characterized by folding and trafficking defects, resulting in decreased functional expression of the protein on the plasma membrane. Several classes of small molecules, named correctors, have been developed to rescue defective F508del CFTR. Although individual correctors failed to improve the clinical status of CF patients carrying the F508del mutation, better results were obtained using correctors combinations. These results were obtained according to the premise that the administration of correctors having different sites of action should enhance F508del CFTR rescue. We investigated the putative site of action of an aminoarylthiazole 4-(3-chlorophenyl)-N-(3-(methylthio)phenyl)thiazol-2-amine, named FCG, with proven CFTR corrector activity, and its synergistic effect with the corrector VX809. We found that neither the total expression nor the maturation of WT CFTR transiently expressed in human embryonic kidney 293 cells was influenced by FCG, administrated alone or in combination with VX809. On the contrary, FCG was able to enhance F508del CFTR total expression, and its combination with VX809 provided a further effect, being able to increase not only the total expression but also the maturation of the mutant protein. Analyses on different CFTR domains and groups of domains, heterologously expressed in HEK293 cells, show that NBD2 is necessary for FCG corrector activity. Molecular modelling analyses suggest that FCG interacts with a putative region located into the NBD2, ascribing this molecule to class II correctors. Our study indicates that the continuous development and testing of combinations of correctors targeting different structural and functional defects of mutant CFTR is the best strategy to ensure a valuable therapeutic perspective to a larger cohort of CF patients.
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