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Elbahnsi A, Dudas B, Cisternino S, Declèves X, Miteva MA. Mechanistic insights into P-glycoprotein ligand transport and inhibition revealed by enhanced molecular dynamics simulations. Comput Struct Biotechnol J 2024; 23:2548-2564. [PMID: 38989058 PMCID: PMC11233806 DOI: 10.1016/j.csbj.2024.06.010] [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: 05/02/2024] [Revised: 06/07/2024] [Accepted: 06/07/2024] [Indexed: 07/12/2024] Open
Abstract
P-glycoprotein (P-gp) plays a crucial role in cellular detoxification and drug efflux processes, transitioning between inward-facing (IF) open, occluded, and outward-facing (OF) states to facilitate substrate transport. Its role is critical in cancer therapy, where P-gp contributes to the multidrug resistance phenotype. In our study, classical and enhanced molecular dynamics (MD) simulations were conducted to dissect the structural and functional features of the P-gp conformational states. Our advanced MD simulations, including kinetically excited targeted MD (ketMD) and adiabatic biasing MD (ABMD), provided deeper insights into state transition and translocation mechanisms. Our findings suggest that the unkinking of TM4 and TM10 helices is a prerequisite for correctly achieving the outward conformation. Simulations of the IF-occluded conformations, characterized by kinked TM4 and TM10 helices, consistently demonstrated altered communication between the transmembrane domains (TMDs) and nucleotide binding domain 2 (NBD2), suggesting the implication of this interface in inhibiting P-gp's efflux function. A particular emphasis was placed on the unstructured linker segment connecting the NBD1 to TMD2 and its role in the transporter's dynamics. With the linker present, we specifically noticed a potential entrance of cholesterol (CHOL) through the TM4-TM6 portal, shedding light on crucial residues involved in accommodating CHOL. We therefore suggest that this entry mechanism could be employed for some P-gp substrates or inhibitors. Our results provide critical data for understanding P-gp functioning and developing new P-gp inhibitors for establishing more effective strategies against multidrug resistance.
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Affiliation(s)
- Ahmad Elbahnsi
- Université Paris Cité, CNRS UMR 8038 CiTCoM, Inserm U1268 MCTR, Paris, France
| | - Balint Dudas
- Université Paris Cité, CNRS UMR 8038 CiTCoM, Inserm U1268 MCTR, Paris, France
| | - Salvatore Cisternino
- Université Paris Cité, Inserm UMRS 1144, Optimisation Thérapeutique en Neuropsychopharmacologie, Paris, France
| | - Xavier Declèves
- Université Paris Cité, Inserm UMRS 1144, Optimisation Thérapeutique en Neuropsychopharmacologie, Paris, France
| | - Maria A. Miteva
- Université Paris Cité, CNRS UMR 8038 CiTCoM, Inserm U1268 MCTR, Paris, France
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2
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Pérez-Mitta G, Sezgin Y, Wang W, MacKinnon R. Freestanding bilayer microscope for single-molecule imaging of membrane proteins. SCIENCE ADVANCES 2024; 10:eado4722. [PMID: 38905330 PMCID: PMC11192074 DOI: 10.1126/sciadv.ado4722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Accepted: 05/16/2024] [Indexed: 06/23/2024]
Abstract
Integral membrane proteins (IMPs) constitute a large fraction of organismal proteomes, playing fundamental roles in physiology and disease. Despite their importance, the mechanisms underlying dynamic features of IMPs, such as anomalous diffusion, protein-protein interactions, and protein clustering, remain largely unknown due to the high complexity of cell membrane environments. Available methods for in vitro studies are insufficient to study IMP dynamics systematically. This publication introduces the freestanding bilayer microscope (FBM), which combines the advantages of freestanding bilayers with single-particle tracking. The FBM, based on planar lipid bilayers, enables the study of IMP dynamics with single-molecule resolution and unconstrained diffusion. This paper benchmarks the FBM against total internal reflection fluorescence imaging on supported bilayers and is used here to estimate ion channel open probability and to examine the diffusion behavior of an ion channel in phase-separated bilayers. The FBM emerges as a powerful tool to examine membrane protein/lipid organization and dynamics to understand cell membrane processes.
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Affiliation(s)
- Gonzalo Pérez-Mitta
- Laboratory of Molecular Neurobiology and Biophysics, Howard Hughes Medical Institute, The Rockefeller University, New York, NY, USA
| | - Yeliz Sezgin
- Laboratory of Molecular Neurobiology and Biophysics, Howard Hughes Medical Institute, The Rockefeller University, New York, NY, USA
| | | | - Roderick MacKinnon
- Laboratory of Molecular Neurobiology and Biophysics, Howard Hughes Medical Institute, The Rockefeller University, New York, NY, USA
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3
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Sun Z, Liang C, Ling Y, Chen Y, Ma Z, Xu Y, Liu Z. A study on the subchronic toxicity of triclocarban to the early-life development of oryzias melastigma and focused on the analysis of osmoregulatory regulation mechanisms. Comp Biochem Physiol C Toxicol Pharmacol 2024; 279:109882. [PMID: 38437996 DOI: 10.1016/j.cbpc.2024.109882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 01/27/2024] [Accepted: 02/29/2024] [Indexed: 03/06/2024]
Abstract
Triclocarban (TCC), a novel antimicrobial agent found in personal care products, has been extensively detected in marine environments. However, research on the toxic effects of TCC on marine organisms remains inadequate. This study delved into the subchronic toxic effects of TCC on the early life stages of marine medaka (Oryzias melastigma, O. melastigma), revealing that TCC could reduce embryo heart rate and hatching rate while diminishing the survival rate of larvae. Biomarker assays indicated that TCC could inflict damage on the embryos' antioxidant and nervous systems. Transcriptomic analysis suggested that TCC could impact cell growth, reproduction, and various life processes, activating cancer signaling pathways, increasing the likelihood of cancer, and exerting toxic effects on the immune and osmoregulatory systems. To validate and enhance our understanding of TCC's unique toxic impact on the osmoregulatory system of O. melastigma, we conducted homology modeling and molecular docking analyses on the protein involved in osmoregulation. The study intuitively revealed the potential binding affinity of TCC to sodium/potassium-transporting ATPase subunit alph (ATP1A1), indicating its ability to disrupt osmotic balance in marine fish by affecting this target protein. In summary, the results of this study will further enhance our comprehension of the potential toxic effects and mechanisms of TCC on the early stages of marine fish, with a specific focus on its unique toxic effects in osmoregulation.
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Affiliation(s)
- Zhecheng Sun
- School of Environmental Science and Engineering, Nanjing tech university, Nanjing 211816, China
| | - Chuan Liang
- School of Environmental Science and Engineering, Nanjing tech university, Nanjing 211816, China
| | - Yunzhe Ling
- School of Environmental Science and Engineering, Nanjing tech university, Nanjing 211816, China
| | - Yang Chen
- School of Environmental Science and Engineering, Nanjing tech university, Nanjing 211816, China
| | - Zhengzhuo Ma
- School of Environmental Science and Engineering, Nanjing tech university, Nanjing 211816, China
| | - Yanhua Xu
- School of Environmental Science and Engineering, Nanjing tech university, Nanjing 211816, China
| | - Zhiying Liu
- School of Environmental Science and Engineering, Nanjing tech university, Nanjing 211816, China.
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4
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Han X, Li D, Zhu Y, Schneider-Futschik EK. Recommended Tool Compounds for Modifying the Cystic Fibrosis Transmembrane Conductance Regulator Channel Variants. ACS Pharmacol Transl Sci 2024; 7:933-950. [PMID: 38633590 PMCID: PMC11019735 DOI: 10.1021/acsptsci.3c00362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 02/20/2024] [Accepted: 02/23/2024] [Indexed: 04/19/2024]
Abstract
Cystic fibrosis (CF) is a genetic disorder arising from variations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, leading to multiple organ system defects. CFTR tool compounds are molecules that can modify the activity of the CFTR channel. Especially, patients that are currently not able to benefit from approved CFTR modulators, such as patients with rare CFTR variants, benefit from further research in discovering novel tools to modulate CFTR. This Review explores the development and classification of CFTR tool compounds, including CFTR blockers (CFTRinh-172, GlyH-101), potentiators (VRT-532, Genistein), correctors (VRT-325, Corr-4a), and other approved and unapproved modulators, with detailed descriptions and discussions for each compound. The challenges and future directions in targeting rare variants and optimizing drug delivery, and the potential synergistic effects in combination therapies are outlined. CFTR modulation holds promise not only for CF treatment but also for generating CF models that contribute to CF research and potentially treating other diseases such as secretory diarrhea. Therefore, continued research on CFTR tool compounds is critical.
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Affiliation(s)
- XiaoXuan Han
- Department of Biochemistry & Pharmacology,
School of Biomedical Sciences, Faculty of Medicine, Dentistry and
Health Sciences, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Danni Li
- Department of Biochemistry & Pharmacology,
School of Biomedical Sciences, Faculty of Medicine, Dentistry and
Health Sciences, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Yimin Zhu
- Department of Biochemistry & Pharmacology,
School of Biomedical Sciences, Faculty of Medicine, Dentistry and
Health Sciences, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Elena K. Schneider-Futschik
- Department of Biochemistry & Pharmacology,
School of Biomedical Sciences, Faculty of Medicine, Dentistry and
Health Sciences, The University of Melbourne, Parkville, VIC 3010, Australia
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5
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Young PG, Levring J, Fiedorczuk K, Blanchard SC, Chen J. Structural basis for CFTR inhibition by CFTR inh-172. Proc Natl Acad Sci U S A 2024; 121:e2316675121. [PMID: 38422021 DOI: 10.1073/pnas.2316675121] [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: 09/25/2023] [Accepted: 01/12/2024] [Indexed: 03/02/2024] Open
Abstract
The cystic fibrosis transmembrane conductance regulator (CFTR) is an anion channel that regulates electrolyte and fluid balance in epithelial tissues. While activation of CFTR is vital to treating cystic fibrosis, selective inhibition of CFTR is a potential therapeutic strategy for secretory diarrhea and autosomal dominant polycystic kidney disease. Although several CFTR inhibitors have been developed by high-throughput screening, their modes of action remain elusive. In this study, we determined the structure of CFTR in complex with the inhibitor CFTRinh-172 to an overall resolution of 2.7 Å by cryogenic electron microscopy. We observe that CFTRinh-172 binds inside the pore near transmembrane helix 8, a critical structural element that links adenosine triphosphate hydrolysis with channel gating. Binding of CFTRinh-172 stabilizes a conformation in which the chloride selectivity filter is collapsed, and the pore is blocked from the extracellular side of the membrane. Single-molecule fluorescence resonance energy transfer experiments indicate that CFTRinh-172 inhibits channel gating without compromising nucleotide-binding domain dimerization. Together, these data reconcile previous biophysical observations and provide a molecular basis for the activity of this widely used CFTR inhibitor.
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Affiliation(s)
- Paul G Young
- Laboratory of Membrane Biology and Biophysics, The Rockefeller University, New York, NY 10065
- Weill Cornell/Rockefeller/Sloan Kettering Tri-Institutional MD-PhD Program, New York, NY 10065
| | - Jesper Levring
- Laboratory of Membrane Biology and Biophysics, The Rockefeller University, New York, NY 10065
| | - Karol Fiedorczuk
- Laboratory of Membrane Biology and Biophysics, The Rockefeller University, New York, NY 10065
| | - Scott C Blanchard
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38101
| | - Jue Chen
- Laboratory of Membrane Biology and Biophysics, The Rockefeller University, New York, NY 10065
- HHMI, The Rockefeller University, New York, NY 10065
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6
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Levring J, Chen J. Structural identification of a selectivity filter in CFTR. Proc Natl Acad Sci U S A 2024; 121:e2316673121. [PMID: 38381791 PMCID: PMC10907310 DOI: 10.1073/pnas.2316673121] [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: 09/25/2023] [Accepted: 01/19/2024] [Indexed: 02/23/2024] Open
Abstract
The cystic fibrosis transmembrane conductance regulator (CFTR) is a chloride channel that regulates transepithelial salt and fluid homeostasis. CFTR dysfunction leads to reduced chloride secretion into the mucosal lining of epithelial tissues, thereby causing the inherited disease cystic fibrosis. Although several structures of CFTR are available, our understanding of the ion-conduction pathway is incomplete. In particular, the route that connects the cytosolic vestibule with the extracellular space has not been clearly defined, and the structure of the open pore remains elusive. Furthermore, although many residues have been implicated in altering the selectivity of CFTR, the structure of the "selectivity filter" has yet to be determined. In this study, we identify a chloride-binding site at the extracellular ends of transmembrane helices 1, 6, and 8, where a dehydrated chloride is coordinated by residues G103, R334, F337, T338, and Y914. Alterations to this site, consistent with its function as a selectivity filter, affect ion selectivity, conductance, and open channel block. This selectivity filter is accessible from the cytosol through a large inner vestibule and opens to the extracellular solvent through a narrow portal. The identification of a chloride-binding site at the intra- and extracellular bridging point leads us to propose a complete conductance path that permits dehydrated chloride ions to traverse the lipid bilayer.
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Affiliation(s)
- Jesper Levring
- Laboratory of Membrane Biology and Biophysics, The Rockefeller University, New York, NY10065
| | - Jue Chen
- Laboratory of Membrane Biology and Biophysics, The Rockefeller University, New York, NY10065
- HHMI, The Rockefeller University, New York, NY10065
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7
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Ferreira FC, Buarque CD, Lopes-Pacheco M. Organic Synthesis and Current Understanding of the Mechanisms of CFTR Modulator Drugs Ivacaftor, Tezacaftor, and Elexacaftor. Molecules 2024; 29:821. [PMID: 38398574 PMCID: PMC10891718 DOI: 10.3390/molecules29040821] [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: 12/31/2023] [Revised: 02/02/2024] [Accepted: 02/06/2024] [Indexed: 02/25/2024] Open
Abstract
The monogenic rare disease Cystic Fibrosis (CF) is caused by mutations in the gene encoding the CF transmembrane conductance (CFTR) protein, an anion channel expressed at the apical plasma membrane of epithelial cells. The discovery and subsequent development of CFTR modulators-small molecules acting on the basic molecular defect in CF-have revolutionized the standard of care for people with CF (PwCF), thus drastically improving their clinical features, prognosis, and quality of life. Currently, four of these drugs are approved for clinical use: potentiator ivacaftor (VX-770) alone or in combination with correctors lumacaftor, (VX-809), tezacaftor (VX-661), and elexacaftor (VX-445). Noteworthily, the triple combinatorial therapy composed of ivacaftor, tezacaftor, and elexacaftor constitutes the most effective modulator therapy nowadays for the majority of PwCF. In this review, we exploit the organic synthesis of ivacaftor, tezacaftor, and elexacaftor by providing a retrosynthetic drug analysis for these CFTR modulators. Furthermore, we describe the current understanding of the mechanisms of action (MoA's) of these compounds by discussing several studies that report the key findings on the molecular mechanisms underlying their action on the CFTR protein.
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Affiliation(s)
- Filipa C. Ferreira
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisbon, 1749-016 Lisbon, Portugal
| | - Camilla D. Buarque
- Department of Chemistry, Pontifical Catholic University of Rio de Janeiro (PUC-Rio), Rio de Janeiro 22435-900, RJ, Brazil
| | - Miquéias Lopes-Pacheco
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisbon, 1749-016 Lisbon, Portugal
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8
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Mao YX, Chen ZP, Wang L, Wang J, Zhou CZ, Hou WT, Chen Y. Transport mechanism of human bilirubin transporter ABCC2 tuned by the inter-module regulatory domain. Nat Commun 2024; 15:1061. [PMID: 38316776 PMCID: PMC10844203 DOI: 10.1038/s41467-024-45337-5] [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: 07/06/2023] [Accepted: 01/19/2024] [Indexed: 02/07/2024] Open
Abstract
Bilirubin is mainly generated from the breakdown of heme when red blood cells reach the end of their lifespan. Accumulation of bilirubin in human body usually leads to various disorders, including jaundice and liver disease. Bilirubin is conjugated in hepatocytes and excreted to bile duct via the ATP-binding cassette transporter ABCC2, dysfunction of which would lead to Dubin-Johnson syndrome. Here we determine the structures of ABCC2 in the apo, substrate-bound and ATP/ADP-bound forms using the cryo-electron microscopy, exhibiting a full transporter with a regulatory (R) domain inserted between the two half modules. Combined with substrate-stimulated ATPase and transport activity assays, structural analysis enables us to figure out transport cycle of ABCC2 with the R domain adopting various conformations. At the rest state, the R domain binding to the translocation cavity functions as an affinity filter that allows the substrates of high affinity to be transported in priority. Upon substrate binding, the R domain is expelled from the cavity and docks to the lateral of transmembrane domain following ATP hydrolysis. Our findings provide structural insights into a transport mechanism of ABC transporters finely tuned by the R domain.
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Affiliation(s)
- Yao-Xu Mao
- Department of Endocrinology, Institute of Endocrine and Metabolic Diseases, The First Affiliated Hospital of USTC, and Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, 230027, China
- School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, 230027, China
- Biomedical Sciences and Health Laboratory of Anhui Province, University of Science and Technology of China, Hefei, Anhui, 230027, China
| | - Zhi-Peng Chen
- Department of Endocrinology, Institute of Endocrine and Metabolic Diseases, The First Affiliated Hospital of USTC, and Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, 230027, China
- School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, 230027, China
| | - Liang Wang
- Department of Endocrinology, Institute of Endocrine and Metabolic Diseases, The First Affiliated Hospital of USTC, and Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, 230027, China
- School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, 230027, China
| | - Jie Wang
- Department of Endocrinology, Institute of Endocrine and Metabolic Diseases, The First Affiliated Hospital of USTC, and Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, 230027, China
- School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, 230027, China
| | - Cong-Zhao Zhou
- School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, 230027, China.
- Biomedical Sciences and Health Laboratory of Anhui Province, University of Science and Technology of China, Hefei, Anhui, 230027, China.
| | - Wen-Tao Hou
- Department of Endocrinology, Institute of Endocrine and Metabolic Diseases, The First Affiliated Hospital of USTC, and Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, 230027, China.
- School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, 230027, China.
- Biomedical Sciences and Health Laboratory of Anhui Province, University of Science and Technology of China, Hefei, Anhui, 230027, China.
| | - Yuxing Chen
- Department of Endocrinology, Institute of Endocrine and Metabolic Diseases, The First Affiliated Hospital of USTC, and Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, 230027, China.
- School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, 230027, China.
- Biomedical Sciences and Health Laboratory of Anhui Province, University of Science and Technology of China, Hefei, Anhui, 230027, China.
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9
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Marunaka Y. The Role of Ion-Transporting Proteins in Human Disease. Int J Mol Sci 2024; 25:1726. [PMID: 38339004 PMCID: PMC10855098 DOI: 10.3390/ijms25031726] [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: 01/16/2024] [Accepted: 01/22/2024] [Indexed: 02/12/2024] Open
Abstract
This Special Issue focuses on the significance of ion-transporting proteins, such as ion channels and transporters, providing evidence for their significant contribution to bodily and cellular functions via the regulation of signal transduction and ionic environments [...].
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Affiliation(s)
- Yoshinori Marunaka
- Medical Research Institute, Kyoto Industrial Health Association, 67 Kitatsuboi-cho, Nishinokyo, Nakagyo-ku, Kyoto 604-8472, Japan;
- Research Organization of Science and Technology, Ritsumeikan University, Kusatsu 525-8577, Japan
- Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
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10
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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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11
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Spelier S, de Winter-de Groot K, Keijzer-Nieuwenhuijze N, Liem Y, van der Ent K, Beekman J, Kamphuis LS. Organoid-guided synergistic treatment of minimal function CFTR mutations with CFTR modulators, roflumilast and simvastatin: a personalised approach. Eur Respir J 2024; 63:2300770. [PMID: 37857424 PMCID: PMC10809127 DOI: 10.1183/13993003.00770-2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 09/23/2023] [Indexed: 10/21/2023]
Abstract
Highly effective cystic fibrosis transmembrane conductance regulator (CFTR) protein-targeting modulator therapies (HEMTs) facilitate strong clinical improvements in a large proportion of people with cystic fibrosis (CF) [1, 2]. More specifically, the European Medicines Agency and US Food and Drug Administration (FDA) approved combination of the CFTR modulators elexacaftor/tezacaftor/ivacaftor (ETI) for people with CF with at least one F508del allele, while the FDA extended eligibility for several rare genotypes [3, 4]. However, 10–15% of those with CF carry CFTR mutations that are unresponsive to HEMTs as monotherapy [1]; furthermore, some suffer from HEMT intolerance, and HEMTs are sometimes not accessible due to practical challenges, such as lack of access due to high costs or legislation and approval challenges. Consequently, the focus in the CF research field has shifted towards filling the unmet clinical need for the people with CF that will not benefit from HEMTs. This study describes how preclinical research has guided a successful personalised clinical treatment regimen in a person with minimal function CFTR, upon a synergistic treatment regimen consisting of CFTR modulators, simvastatin and roflumilast https://bit.ly/3rDTHZL
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Affiliation(s)
- Sacha Spelier
- Department of Pediatric Respiratory Medicine, Wilhelmina Children's Hospital, University Medical Center, Utrecht University, Utrecht, The Netherlands
- Regenerative Medicine Utrecht, University Medical Center, Utrecht University, Utrecht, The Netherlands
| | - Karin de Winter-de Groot
- Department of Pediatric Respiratory Medicine, Wilhelmina Children's Hospital, University Medical Center, Utrecht University, Utrecht, The Netherlands
| | - Natascha Keijzer-Nieuwenhuijze
- Department of Pediatric Respiratory Medicine, Wilhelmina Children's Hospital, University Medical Center, Utrecht University, Utrecht, The Netherlands
- Regenerative Medicine Utrecht, University Medical Center, Utrecht University, Utrecht, The Netherlands
| | - Yves Liem
- Department of Clinical Pharmacy, Wilhelmina Children's Hospital, University Medical Center, Utrecht University, Utrecht, The Netherlands
| | - Kors van der Ent
- Department of Pediatric Respiratory Medicine, Wilhelmina Children's Hospital, University Medical Center, Utrecht University, Utrecht, The Netherlands
| | - Jeffrey Beekman
- Department of Pediatric Respiratory Medicine, Wilhelmina Children's Hospital, University Medical Center, Utrecht University, Utrecht, The Netherlands
- Regenerative Medicine Utrecht, University Medical Center, Utrecht University, Utrecht, The Netherlands
- J. Beekman and L.S. Kamphuis contributed equally to this article as lead authors and supervised the work
| | - Lieke S Kamphuis
- Department of Respiratory Medicine, Erasmus University Medical Center, Rotterdam, The Netherlands
- J. Beekman and L.S. Kamphuis contributed equally to this article as lead authors and supervised the work
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Bolger GB. Therapeutic Targets and Precision Medicine in COPD: Inflammation, Ion Channels, Both, or Neither? Int J Mol Sci 2023; 24:17363. [PMID: 38139192 PMCID: PMC10744217 DOI: 10.3390/ijms242417363] [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: 11/13/2023] [Revised: 12/04/2023] [Accepted: 12/09/2023] [Indexed: 12/24/2023] Open
Abstract
The development of a wider range of therapeutic options is a key objective in drug discovery for chronic obstructive pulmonary disease (COPD). Fundamental advances in lung biology have the potential to greatly expand the number of therapeutic targets in COPD. The recently reported successful Phase 3 clinical trial of the first biologic agent for COPD, the monoclonal antibody dupilumab, adds additional support to the importance of targeting inflammatory pathways in COPD. However, numerous other cellular mechanisms are important targets in COPD therapeutics, including airway remodeling, the CFTR ion channel, and mucociliary function. Some of these emerging targets can be exploited by the expanded use of existing COPD drugs, such as roflumilast, while targeting others will require the development of novel molecular entities. The identification of additional therapeutic targets and agents has the potential to greatly expand the value of using clinical and biomarker data to classify COPD into specific subsets, each of which can be predictive of an enhanced response to specific subset(s) of targeted therapies. The author reviews established and emerging drug targets in COPD and uses this as a framework to define a novel classification of COPD based on therapeutic targets. This novel classification has the potential to enhance precision medicine in COPD patient care and to accelerate clinical trials and pre-clinical drug discovery efforts.
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Affiliation(s)
- Graeme B Bolger
- BZI Pharma LLC, 1500 1st Ave N., Unit 36, Birmingham, AL 35203-1872, USA
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Wang J, Li X, Wang F, Cheng M, Mao Y, Fang S, Wang L, Zhou C, Hou W, Chen Y. Placing steroid hormones within the human ABCC3 transporter reveals a compatible amphiphilic substrate-binding pocket. EMBO J 2023; 42:e113415. [PMID: 37485728 PMCID: PMC10476276 DOI: 10.15252/embj.2022113415] [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: 12/31/2022] [Revised: 06/15/2023] [Accepted: 06/20/2023] [Indexed: 07/25/2023] Open
Abstract
The human ABC transporter ABCC3 (also known as MRP3) transports a wide spectrum of substrates, including endogenous metabolites and exogenous drugs. Accordingly, it participates in multiple physiological processes and is involved in diverse human diseases such as intrahepatic cholestasis of pregnancy, which is caused by the intracellular accumulation of bile acids and estrogens. Here, we report three cryogenic electron microscopy structures of ABCC3: in the apo-form and in complexed forms bound to either the conjugated sex hormones β-estradiol 17-(β-D-glucuronide) and dehydroepiandrosterone sulfate. For both hormones, the steroid nuclei that superimpose against each other occupy the hydrophobic center of the transport cavity, whereas the two conjugation groups are separated and fixed by the hydrophilic patches in two transmembrane domains. Structural analysis combined with site-directed mutagenesis and ATPase activity assays revealed that ABCC3 possesses an amphiphilic substrate-binding pocket able to hold either conjugated hormone in an asymmetric pattern. These data build on consensus features of the substrate-binding pocket of MRPs and provide a structural platform for the rational design of inhibitors.
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Affiliation(s)
- Jie Wang
- Department of Endocrinology, Institute of Endocrine and Metabolic Diseases, The First Affiliated Hospital of USTC, and Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiChina
- Biomedical Sciences and Health Laboratory of Anhui ProvinceUniversity of Science and Technology of ChinaHefeiChina
| | - Xu Li
- Department of Endocrinology, Institute of Endocrine and Metabolic Diseases, The First Affiliated Hospital of USTC, and Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiChina
- Biomedical Sciences and Health Laboratory of Anhui ProvinceUniversity of Science and Technology of ChinaHefeiChina
| | - Fang‐Fang Wang
- Department of Endocrinology, Institute of Endocrine and Metabolic Diseases, The First Affiliated Hospital of USTC, and Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiChina
- Biomedical Sciences and Health Laboratory of Anhui ProvinceUniversity of Science and Technology of ChinaHefeiChina
| | - Meng‐Ting Cheng
- Department of Endocrinology, Institute of Endocrine and Metabolic Diseases, The First Affiliated Hospital of USTC, and Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiChina
- Biomedical Sciences and Health Laboratory of Anhui ProvinceUniversity of Science and Technology of ChinaHefeiChina
| | - Yao‐Xu Mao
- Department of Endocrinology, Institute of Endocrine and Metabolic Diseases, The First Affiliated Hospital of USTC, and Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiChina
- Biomedical Sciences and Health Laboratory of Anhui ProvinceUniversity of Science and Technology of ChinaHefeiChina
| | - Shu‐Cheng Fang
- Department of Endocrinology, Institute of Endocrine and Metabolic Diseases, The First Affiliated Hospital of USTC, and Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiChina
- Biomedical Sciences and Health Laboratory of Anhui ProvinceUniversity of Science and Technology of ChinaHefeiChina
| | - Liang Wang
- Biomedical Sciences and Health Laboratory of Anhui ProvinceUniversity of Science and Technology of ChinaHefeiChina
| | - Cong‐Zhao Zhou
- Department of Endocrinology, Institute of Endocrine and Metabolic Diseases, The First Affiliated Hospital of USTC, and Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiChina
- Biomedical Sciences and Health Laboratory of Anhui ProvinceUniversity of Science and Technology of ChinaHefeiChina
| | - Wen‐Tao Hou
- Department of Endocrinology, Institute of Endocrine and Metabolic Diseases, The First Affiliated Hospital of USTC, and Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiChina
- Biomedical Sciences and Health Laboratory of Anhui ProvinceUniversity of Science and Technology of ChinaHefeiChina
| | - Yuxing Chen
- Department of Endocrinology, Institute of Endocrine and Metabolic Diseases, The First Affiliated Hospital of USTC, and Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiChina
- Biomedical Sciences and Health Laboratory of Anhui ProvinceUniversity of Science and Technology of ChinaHefeiChina
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