1
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Farinha CM, Santos L, Ferreira JF. Cell type-specific regulation of CFTR trafficking-on the verge of progress. Front Cell Dev Biol 2024; 12:1338892. [PMID: 38505263 PMCID: PMC10949533 DOI: 10.3389/fcell.2024.1338892] [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: 11/15/2023] [Accepted: 02/21/2024] [Indexed: 03/21/2024] Open
Abstract
Trafficking of the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) protein is a complex process that starts with its biosynthesis and folding in the endoplasmic reticulum. Exit from the endoplasmic reticulum (ER) is coupled with the acquisition of a compact structure that can be processed and traffic through the secretory pathway. Once reaching its final destination-the plasma membrane, CFTR stability is regulated through interaction with multiple protein partners that are involved in its post-translation modification, connecting the channel to several signaling pathways. The complexity of the process is further boosted when analyzed in the context of the airway epithelium. Recent advances have characterized in detail the different cell types that compose the surface epithelium and shifted the paradigm on which cells express CFTR and on their individual and combined contribution to the total expression (and function) of this chloride/bicarbonate channel. Here we review CFTR trafficking and its relationship with the knowledge on the different cell types of the airway epithelia. We explore the crosstalk between these two areas and discuss what is still to be clarified and how this can be used to develop more targeted therapies for CF.
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Affiliation(s)
- Carlos M. Farinha
- Faculty of Sciences, BioISI—Biosystems and Integrative Sciences Institute, University of Lisboa, Lisboa, Portugal
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2
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Rumpf M, Pautz S, Drebes B, Herberg FW, Müller HAJ. Microtubule-Associated Serine/Threonine (MAST) Kinases in Development and Disease. Int J Mol Sci 2023; 24:11913. [PMID: 37569286 PMCID: PMC10419289 DOI: 10.3390/ijms241511913] [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: 06/28/2023] [Revised: 07/17/2023] [Accepted: 07/19/2023] [Indexed: 08/13/2023] Open
Abstract
Microtubule-Associated Serine/Threonine (MAST) kinases represent an evolutionary conserved branch of the AGC protein kinase superfamily in the kinome. Since the discovery of the founding member, MAST2, in 1993, three additional family members have been identified in mammals and found to be broadly expressed across various tissues, including the brain, heart, lung, liver, intestine and kidney. The study of MAST kinases is highly relevant for unraveling the molecular basis of a wide range of different human diseases, including breast and liver cancer, myeloma, inflammatory bowel disease, cystic fibrosis and various neuronal disorders. Despite several reports on potential substrates and binding partners of MAST kinases, the molecular mechanisms that would explain their involvement in human diseases remain rather obscure. This review will summarize data on the structure, biochemistry and cell and molecular biology of MAST kinases in the context of biomedical research as well as organismal model systems in order to provide a current profile of this field.
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Affiliation(s)
- Marie Rumpf
- Department of Developmental Genetics, Institute of Biology, University of Kassel, 34321 Kassel, Germany; (M.R.)
| | - Sabine Pautz
- Department of Biochemistry, Institute of Biology, University of Kassel, 34321 Kassel, Germany
| | - Benedikt Drebes
- Department of Developmental Genetics, Institute of Biology, University of Kassel, 34321 Kassel, Germany; (M.R.)
| | - Friedrich W. Herberg
- Department of Biochemistry, Institute of Biology, University of Kassel, 34321 Kassel, Germany
| | - Hans-Arno J. Müller
- Department of Developmental Genetics, Institute of Biology, University of Kassel, 34321 Kassel, Germany; (M.R.)
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3
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Iazzi M, Sadeghi S, Gupta GD. A Proteomic Survey of the Cystic Fibrosis Transmembrane Conductance Regulator Surfaceome. Int J Mol Sci 2023; 24:11457. [PMID: 37511222 PMCID: PMC10380767 DOI: 10.3390/ijms241411457] [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: 06/07/2023] [Revised: 07/08/2023] [Accepted: 07/12/2023] [Indexed: 07/30/2023] Open
Abstract
The aim of this review article is to collate recent contributions of proteomic studies to cystic fibrosis transmembrane conductance regulator (CFTR) biology. We summarize advances from these studies and create an accessible resource for future CFTR proteomic efforts. We focus our attention on the CFTR interaction network at the cell surface, thus generating a CFTR 'surfaceome'. We review the main findings about CFTR interactions and highlight several functional categories amongst these that could lead to the discovery of potential biomarkers and drug targets for CF.
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Affiliation(s)
| | | | - Gagan D. Gupta
- Department of Chemistry and Biology, Toronto Metropolitan University, Toronto, ON M5B 2K3, Canada
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4
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Stillger K, Neundorf I. Cell-permeable peptide-based delivery vehicles useful for subcellular targeting and beyond. Cell Signal 2023:110796. [PMID: 37423344 DOI: 10.1016/j.cellsig.2023.110796] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 07/01/2023] [Accepted: 07/04/2023] [Indexed: 07/11/2023]
Abstract
Personal medicine aims to provide tailor-made diagnostics and treatments and has been emerged as a promising but challenging strategy during the last years. This includes the active delivery and localization of a therapeutic compound to a targeted site of action within a cell. An example being targeting the interference of a distinct protein-protein interaction (PPI) within the cell nucleus, mitochondria or other subcellular location. Therefore, not only the cell membrane has to be overcome but also the final intracellular destination has to be reached. One approach which fulfills both requirements is to use short peptide sequences that are able to translocate into cells as targeting and delivery vehicles. In fact, recent progress in this field demonstrates how these tools can modulate the pharmacological parameters of a drug without compromising its biological activity. Beside classical targets that are addressed by various small molecule drugs such as receptors, enzymes, or ion channels, PPIs have received increasing attention as potential therapeutic targets. Within this review, we will provide a recent update on cell-permeable peptides targeting subcellular destinations. We include chimeric peptide probes that combine cell-penetrating peptides (CPPs) and a targeting sequence, as well peptides having intrinsic cell-permeability and which are often used to target PPIs.
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Affiliation(s)
- Katharina Stillger
- Institute for Biochemistry, Department of Chemistry, Faculty of Mathematics and Natural Sciences, University of Cologne, Zuelpicher Str. 47a, 50674 Cologne, Germany
| | - Ines Neundorf
- Institute for Biochemistry, Department of Chemistry, Faculty of Mathematics and Natural Sciences, University of Cologne, Zuelpicher Str. 47a, 50674 Cologne, Germany.
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5
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Ford C, Burd CG. GOPC facilitates the sorting of syndecan-1 in polarized epithelial cells. Mol Biol Cell 2022; 33:ar86. [PMID: 35830596 DOI: 10.1091/mbc.e22-05-0165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The trans-Golgi network must coordinate sorting and secretion of proteins and lipids to intracellular organelles and the plasma membrane. During polarization of epithelial cells, changes in the lipidome and the expression and distribution of proteins contribute to the formation of apical and basolateral plasma membrane domains. Previous studies using HeLa cells show that the syndecan-1 transmembrane domain confers sorting within sphingomyelin-rich vesicles in a sphingomyelin secretion pathway. In polarized Madin-Darby canine kidney cells, we reveal differences in the sorting of syndecan-1, whereupon the correct trafficking of the protein is not dependent on its transmembrane domain and changes in sphingomyelin content of cells during polarization. Instead, we reveal that correct basolateral targeting of syndecan-1 requires a full-length PDZ motif in syndecan-1 and the PDZ domain golgin protein GOPC. Moreover, we reveal changes in Golgi morphology elicited by GOPC overexpression. These results suggest that the role of GOPC in sorting syndecan-1 is indirect and likely due to GOPC effects on Golgi organization.
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Affiliation(s)
- Charlotte Ford
- Department of Cell Biology, Yale School of Medicine, New Haven, CT 06520
| | - Christopher G Burd
- Department of Cell Biology, Yale School of Medicine, New Haven, CT 06520
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6
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Seisel Q, Lakumpa I, Josse E, Vivès E, Varilh J, Taulan-Cadars M, Boisguérin P. Highway to Cell: Selection of the Best Cell-Penetrating Peptide to Internalize the CFTR-Stabilizing iCAL36 Peptide. Pharmaceutics 2022; 14:pharmaceutics14040808. [PMID: 35456644 PMCID: PMC9032934 DOI: 10.3390/pharmaceutics14040808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 03/28/2022] [Accepted: 03/31/2022] [Indexed: 11/23/2022] Open
Abstract
Therapeutic peptides have regained interest as they can address unmet medical needs and can be an excellent complement to pharmaceutic small molecules and other macromolecular therapeutics. Over the past decades, correctors and potentiators of the cystic fibrosis transmembrane conductance regulator (CFTR), a chloride ion channel causing cystic fibrosis (CF) when mutated, were developed to reduce the symptoms of the patients. In this context, we have previously designed a CFTR-stabilizing iCAL36 peptide able to further increase the CFTR amount in epithelial cells, thereby resulting in a higher CFTR activity. In the present study, optimization of the peptidyl inhibitor was performed by coupling five different cell-penetrating peptides (CPP), which are Tat, dTat, TatRI (retro-inverso), MPG, and Penetratin. Screening of the internalization properties of these CPP-iCAL36 peptides under different conditions (with or without serum or endocytosis inhibitors, etc.) was performed to select TatRI as the optimal CPP for iCAL36 delivery. More importantly, using this TatRI-iCAL36 peptide, we were able to reveal for the first time an additive increase in the CFTR amount in the presence of VX-445/VX-809 compared to VX-445/VX-809 treatment alone. This finding is a significant contribution to the development of CFTR-stabilizing peptides in addition to currently used treatments (small-molecule correctors or potentiators) for CF patients.
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Affiliation(s)
- Quentin Seisel
- CRBM, University of Montpellier, CNRS UMR 5237, 34000 Montpellier, France
| | - Israpong Lakumpa
- CRBM, University of Montpellier, CNRS UMR 5237, 34000 Montpellier, France
| | - Emilie Josse
- PhyMedExp, Bâtiment Crastes de Paulet, University of Montpellier, INSERM U1046, CNRS UMR 9214, 34000 Montpellier, France
| | - Eric Vivès
- PhyMedExp, Bâtiment Crastes de Paulet, University of Montpellier, INSERM U1046, CNRS UMR 9214, 34000 Montpellier, France
| | - Jessica Varilh
- PhyMedExp, Institut Universitaire de Recherche Clinique, University of Montpellier, INSERM U1046, CNRS UMR 9214, 34000 Montpellier, France
| | - Magali Taulan-Cadars
- PhyMedExp, Institut Universitaire de Recherche Clinique, University of Montpellier, INSERM U1046, CNRS UMR 9214, 34000 Montpellier, France
| | - Prisca Boisguérin
- PhyMedExp, Bâtiment Crastes de Paulet, University of Montpellier, INSERM U1046, CNRS UMR 9214, 34000 Montpellier, France
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7
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Brusa I, Sondo E, Falchi F, Pedemonte N, Roberti M, Cavalli A. Proteostasis Regulators in Cystic Fibrosis: Current Development and Future Perspectives. J Med Chem 2022; 65:5212-5243. [PMID: 35377645 PMCID: PMC9014417 DOI: 10.1021/acs.jmedchem.1c01897] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In cystic fibrosis (CF), the deletion of phenylalanine 508 (F508del) in the CF transmembrane conductance regulator (CFTR) leads to misfolding and premature degradation of the mutant protein. These defects can be targeted with pharmacological agents named potentiators and correctors. During the past years, several efforts have been devoted to develop and approve new effective molecules. However, their clinical use remains limited, as they fail to fully restore F508del-CFTR biological function. Indeed, the search for CFTR correctors with different and additive mechanisms has recently increased. Among them, drugs that modulate the CFTR proteostasis environment are particularly attractive to enhance therapy effectiveness further. This Perspective focuses on reviewing the recent progress in discovering CFTR proteostasis regulators, mainly describing the design, chemical structure, and structure-activity relationships. The opportunities, challenges, and future directions in this emerging and promising field of research are discussed, as well.
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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
| | | | | | - 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
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8
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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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9
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Nardella C, Visconti L, Malagrinò F, Pagano L, Bufano M, Nalli M, Coluccia A, La Regina G, Silvestri R, Gianni S, Toto A. Targeting PDZ domains as potential treatment for viral infections, neurodegeneration and cancer. Biol Direct 2021; 16:15. [PMID: 34641953 PMCID: PMC8506081 DOI: 10.1186/s13062-021-00303-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 09/24/2021] [Indexed: 02/08/2023] Open
Abstract
The interaction between proteins is a fundamental event for cellular life that is generally mediated by specialized protein domains or modules. PDZ domains are the largest class of protein-protein interaction modules, involved in several cellular pathways such as signal transduction, cell-cell junctions, cell polarity and adhesion, and protein trafficking. Because of that, dysregulation of PDZ domain function often causes the onset of pathologies, thus making this family of domains an interesting pharmaceutical target. In this review article we provide an overview of the structural and functional features of PDZ domains and their involvement in the cellular and molecular pathways at the basis of different human pathologies. We also discuss some of the strategies that have been developed with the final goal to hijack or inhibit the interaction of PDZ domains with their ligands. Because of the generally low binding selectivity of PDZ domain and the scarce efficiency of small molecules in inhibiting PDZ binding, this task resulted particularly difficult to pursue and still demands increasing experimental efforts in order to become completely feasible and successful in vivo.
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Affiliation(s)
- Caterina Nardella
- Istituto Pasteur - Fondazione Cenci Bolognetti, Dipartimento di Scienze Biochimiche "A. Rossi Fanelli" and Istituto di Biologia e Patologia Molecolari del CNR, Sapienza Università di Roma, 00185, Rome, Italy
| | - Lorenzo Visconti
- Istituto Pasteur - Fondazione Cenci Bolognetti, Dipartimento di Scienze Biochimiche "A. Rossi Fanelli" and Istituto di Biologia e Patologia Molecolari del CNR, Sapienza Università di Roma, 00185, Rome, Italy
| | - Francesca Malagrinò
- Istituto Pasteur - Fondazione Cenci Bolognetti, Dipartimento di Scienze Biochimiche "A. Rossi Fanelli" and Istituto di Biologia e Patologia Molecolari del CNR, Sapienza Università di Roma, 00185, Rome, Italy
| | - Livia Pagano
- Istituto Pasteur - Fondazione Cenci Bolognetti, Dipartimento di Scienze Biochimiche "A. Rossi Fanelli" and Istituto di Biologia e Patologia Molecolari del CNR, Sapienza Università di Roma, 00185, Rome, Italy
| | - Marianna Bufano
- Laboratory Affiliated with the Institute Pasteur Italy - Cenci Bolognetti Foundation, Department of Drug Chemistry and Technologies, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy
| | - Marianna Nalli
- Laboratory Affiliated with the Institute Pasteur Italy - Cenci Bolognetti Foundation, Department of Drug Chemistry and Technologies, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy
| | - Antonio Coluccia
- Laboratory Affiliated with the Institute Pasteur Italy - Cenci Bolognetti Foundation, Department of Drug Chemistry and Technologies, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy
| | - Giuseppe La Regina
- Laboratory Affiliated with the Institute Pasteur Italy - Cenci Bolognetti Foundation, Department of Drug Chemistry and Technologies, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy
| | - Romano Silvestri
- Laboratory Affiliated with the Institute Pasteur Italy - Cenci Bolognetti Foundation, Department of Drug Chemistry and Technologies, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy.
| | - Stefano Gianni
- Istituto Pasteur - Fondazione Cenci Bolognetti, Dipartimento di Scienze Biochimiche "A. Rossi Fanelli" and Istituto di Biologia e Patologia Molecolari del CNR, Sapienza Università di Roma, 00185, Rome, Italy.
| | - Angelo Toto
- Istituto Pasteur - Fondazione Cenci Bolognetti, Dipartimento di Scienze Biochimiche "A. Rossi Fanelli" and Istituto di Biologia e Patologia Molecolari del CNR, Sapienza Università di Roma, 00185, Rome, Italy.
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10
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Klüssendorf M, Song I, Schau L, Morellini F, Dityatev A, Koliwer J, Kreienkamp HJ. The Golgi-Associated PDZ Domain Protein Gopc/PIST Is Required for Synaptic Targeting of mGluR5. Mol Neurobiol 2021; 58:5618-5634. [PMID: 34383253 PMCID: PMC8599212 DOI: 10.1007/s12035-021-02504-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 07/22/2021] [Indexed: 12/21/2022]
Abstract
In neuronal cells, many membrane receptors interact via their intracellular, C-terminal tails with PSD-95/discs large/ZO-1 (PDZ) domain proteins. Some PDZ proteins act as scaffold proteins. In addition, there are a few PDZ proteins such as Gopc which bind to receptors during intracellular transport. Gopc is localized at the trans-Golgi network (TGN) and binds to a variety of receptors, many of which are eventually targeted to postsynaptic sites. We have analyzed the role of Gopc by knockdown in primary cultured neurons and by generating a conditional Gopc knockout (KO) mouse line. In neurons, targeting of neuroligin 1 (Nlgn1) and metabotropic glutamate receptor 5 (mGlu5) to the plasma membrane was impaired upon depletion of Gopc, whereas NMDA receptors were not affected. In the hippocampus and cortex of Gopc KO animals, expression levels of Gopc-associated receptors were not altered, while their subcellular localization was disturbed. The targeting of mGlu5 to the postsynaptic density was reduced, coinciding with alterations in mGluR-dependent synaptic plasticity and deficiencies in a contextual fear conditioning paradigm. Our data imply Gopc in the correct subcellular sorting of its associated mGlu5 receptor in vivo.
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Affiliation(s)
- Malte Klüssendorf
- Institute for Human Genetics, University Medical Center Hamburg Eppendorf, Hamburg, Germany
| | - Inseon Song
- Molecular Neuroplasticity Group, German Center for Neurodegenerative Diseases (DZNE), 39120, Magdeburg, Germany
| | - Lynn Schau
- Research Group Behavioral Biology, Center for Molecular Neurobiology, University Medical Center Hamburg Eppendorf, Hamburg, Germany
| | - Fabio Morellini
- Research Group Behavioral Biology, Center for Molecular Neurobiology, University Medical Center Hamburg Eppendorf, Hamburg, Germany
| | - Alexander Dityatev
- Molecular Neuroplasticity Group, German Center for Neurodegenerative Diseases (DZNE), 39120, Magdeburg, Germany
- Center for Behavioral Brain Sciences (CBBS), 39106, Magdeburg, Germany
- Medical Faculty, Otto-Von-Guericke University, 39120, Magdeburg, Germany
| | - Judith Koliwer
- Institute for Human Genetics, University Medical Center Hamburg Eppendorf, Hamburg, Germany
| | - Hans-Jürgen Kreienkamp
- Institute for Human Genetics, University Medical Center Hamburg Eppendorf, Hamburg, Germany.
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11
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Wang Y, Gu L, Yang HM, Zhang H. Cystic fibrosis transmembrane conductance regulator-associated ligand protects dopaminergic neurons by differentially regulating metabotropic glutamate receptor 5 in the progression of neurotoxin 6-hydroxydopamine-induced Parkinson's disease model. Neurotoxicology 2021; 84:14-29. [PMID: 33571554 DOI: 10.1016/j.neuro.2021.02.003] [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: 03/22/2020] [Revised: 12/21/2020] [Accepted: 02/04/2021] [Indexed: 10/22/2022]
Abstract
Due to limitations in early diagnosis and treatments of Parkinson's disease (PD), it is necessary to explore the neuropathological changes that occur early in PD progression and to design neuroprotective therapies to prevent or delay the ongoing degeneration process. Metabotropic glutamate receptor 5 (mGlu5) has shown both diagnostic and therapeutic potential in preclinical studies on PD. Clinical trials using mGlu5 negative allosteric modulators to treat PD have, however, raised limitations about the neuroprotective role of mGlu5. It is likely that mGlu5 has different regulatory roles in different stages of PD. Here, we investigated a protective role of cystic fibrosis transmembrane conductance regulator-associated ligand (CAL) in the progression of PD by differential regulation of mGlu5 expression and activity to protect against 6-hydroxydopamine (6-OHDA)-induced neurotoxicity. Following treatment with 6-OHDA, mGlu5 and CAL expressions were elevated in the early stage and reduced in the late stage, both in vitro and in vivo. Activation of mGlu5 in the early stage by (RS)-2-chloro-5-hydroxyphenylglycine, or blocking mGlu5 in the late stage by 2-methyl-6-(phenylethynyl) pyridine, increased cell survival and inhibited apoptosis, but these effects were significantly weakened by knockdown of CAL. CAL alleviated 6-OHDA-induced neurotoxicity by regulating mGlu5-mediated signaling pathways, thereby maintaining the physiological function of mGlu5 in different disease stages. In PD rat model, CAL deficiency aggravated 6-OHDA toxicity on dopaminergic neurons and increased motor dysfunction because of lack of regulation of mGlu5 activity. These data reveal a potential mechanism by which CAL specifically regulates the opposite activity of mGlu5 in progression of PD to protect against neurotoxicity, suggesting that CAL is a favorable endogenous target for the treatment of PD.
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Affiliation(s)
- Yuan Wang
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Key Laboratory of Neural Regeneration and Repair, Beijing Institute for Brain Disorders, Capital Medical University, No. 10 Xitoutiao, You An Men, Beijing, 100069, China
| | - Li Gu
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Key Laboratory of Neural Regeneration and Repair, Beijing Institute for Brain Disorders, Capital Medical University, No. 10 Xitoutiao, You An Men, Beijing, 100069, China
| | - Hui Min Yang
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Key Laboratory of Neural Regeneration and Repair, Beijing Institute for Brain Disorders, Capital Medical University, No. 10 Xitoutiao, You An Men, Beijing, 100069, China
| | - Hong Zhang
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Key Laboratory of Neural Regeneration and Repair, Beijing Institute for Brain Disorders, Capital Medical University, No. 10 Xitoutiao, You An Men, Beijing, 100069, China.
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12
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Dougherty PG, Wellmerling JH, Koley A, Lukowski JK, Hummon AB, Cormet-Boyaka E, Pei D. Cyclic Peptidyl Inhibitors against CAL/CFTR Interaction for Treatment of Cystic Fibrosis. J Med Chem 2020; 63:15773-15784. [PMID: 33314931 PMCID: PMC8011814 DOI: 10.1021/acs.jmedchem.0c01528] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Cystic fibrosis (CF) is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, encoding for a chloride ion channel. Membrane expression of CFTR is negatively regulated by CFTR-associated ligand (CAL). We previously showed that inhibition of the CFTR/CAL interaction with a cell-permeable peptide improves the function of rescued F508del-CFTR. In this study, optimization of the peptidyl inhibitor yielded PGD97, which exhibits a KD value of 6 nM for the CAL PDZ domain, ≥ 130-fold selectivity over closely related PDZ domains, and a serum t1/2 of >24 h. In patient-derived F508del homozygous cells, PGD97 (100 nM) increased short-circuit currents by ∼3-fold and further potentiated the therapeutic effects of small-molecule correctors (e.g., VX-661) by ∼2-fold (with an EC50 of ∼10 nM). Our results suggest that PGD97 may be used as a novel treatment for CF, either as a single agent or in combination with small-molecule correctors/potentiators.
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Affiliation(s)
- Patrick G. Dougherty
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States,Current address: Entrada Therapeutics, 50 Northern Avenue, Boston, MA 02210, United States
| | - Jack H. Wellmerling
- Department of Veterinary Biosciences, The Ohio State University, Columbus, OH 43210, USA
| | - Amritendu Koley
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Jessica K. Lukowski
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, United States
| | - Amanda B. Hummon
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States,Comprehensive Cancer Center, The Ohio State University, Columbus, OH 43210, United States
| | - Estelle Cormet-Boyaka
- Department of Veterinary Biosciences, The Ohio State University, Columbus, OH 43210, USA,Corresponding Author: To whom correspondence should be addressed. Estelle Cormet-Boyaka: . Dehua Pei: Phone: (614) 688-4068;
| | - Dehua Pei
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States,Corresponding Author: To whom correspondence should be addressed. Estelle Cormet-Boyaka: . Dehua Pei: Phone: (614) 688-4068;
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13
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Strub MD, McCray, Jr. PB. Transcriptomic and Proteostasis Networks of CFTR and the Development of Small Molecule Modulators for the Treatment of Cystic Fibrosis Lung Disease. Genes (Basel) 2020; 11:genes11050546. [PMID: 32414011 PMCID: PMC7288469 DOI: 10.3390/genes11050546] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 05/07/2020] [Accepted: 05/08/2020] [Indexed: 12/18/2022] Open
Abstract
Cystic fibrosis (CF) is a lethal autosomal recessive disease caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. The diversity of mutations and the multiple ways by which the protein is affected present challenges for therapeutic development. The observation that the Phe508del-CFTR mutant protein is temperature sensitive provided proof of principle that mutant CFTR could escape proteosomal degradation and retain partial function. Several specific protein interactors and quality control checkpoints encountered by CFTR during its proteostasis have been investigated for therapeutic purposes, but remain incompletely understood. Furthermore, pharmacological manipulation of many CFTR interactors has not been thoroughly investigated for the rescue of Phe508del-CFTR. However, high-throughput screening technologies helped identify several small molecule modulators that rescue CFTR from proteosomal degradation and restore partial function to the protein. Here, we discuss the current state of CFTR transcriptomic and biogenesis research and small molecule therapy development. We also review recent progress in CFTR proteostasis modulators and discuss how such treatments could complement current FDA-approved small molecules.
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Affiliation(s)
- Matthew D. Strub
- Interdisciplinary Graduate Program in Genetics, The University of Iowa, Iowa City, IA 52242, USA;
- Stead Family Department of Pediatrics, The University of Iowa, Iowa City, IA 52242, USA
| | - Paul B. McCray, Jr.
- Interdisciplinary Graduate Program in Genetics, The University of Iowa, Iowa City, IA 52242, USA;
- Stead Family Department of Pediatrics, The University of Iowa, Iowa City, IA 52242, USA
- Correspondence: ; Tel.: +1-(319)-335-6844
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14
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Sala V, Murabito A, Ghigo A. Inhaled Biologicals for the Treatment of Cystic Fibrosis. ACTA ACUST UNITED AC 2020; 13:19-26. [PMID: 30318010 PMCID: PMC6751348 DOI: 10.2174/1872213x12666181012101444] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 10/09/2018] [Accepted: 10/09/2018] [Indexed: 12/20/2022]
Abstract
Background: Cystic Fibrosis (CF), one of the most frequent genetic diseases, is characterized by the production of viscous mucus in several organs. In the lungs, mucus clogs the airways and traps bacteria, leading to recurrent/resistant infections and lung damage. For cystic fibrosis patients, respiratory failure is still lethal in early adulthood since available treatments display incomplete efficacy. Objective: The objective of this review is to extend the current knowledge in the field of available treat-ments for cystic fibrosis. A special focus has been given to inhaled peptide-based drugs. Methods: The current review is based on recent and/or relevant literature and patents already available in various scientific databases, which include PubMed, PubMed Central, Patentscope and Science Direct. The information obtained through these diverse databases is compiled, critically interpreted and presented in the current study. An in-depth but not systematic approach to the specific research question has been adopted. Results: Recently, peptides have been proposed as possible pharmacologic agents for the treatment of respiratory diseases. Of note, peptides are suitable to be administered by inhalation to maximize efficacy and reduce systemic side effects. Moreover, innovative delivery carriers have been developed for drug administration through inhalation, allowing not only protection against proteolysis, but also a prolonged and controlled release. Conclusion: Here, we summarize newly patented peptides that have been developed in the last few years and advanced technologies for inhaled drug delivery to treat cystic fibrosis.
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Affiliation(s)
- Valentina Sala
- Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, University of Torino, Torino, Italy.,S.C. Medicina d'Urgenza, A.O.U. Città della Salute e della Scienza, Molinette Hospital, Torino, Italy
| | - Alessandra Murabito
- Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, University of Torino, Torino, Italy
| | - Alessandra Ghigo
- Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, University of Torino, Torino, Italy
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15
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Regulation of CFTR Biogenesis by the Proteostatic Network and Pharmacological Modulators. Int J Mol Sci 2020; 21:ijms21020452. [PMID: 31936842 PMCID: PMC7013518 DOI: 10.3390/ijms21020452] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 01/06/2020] [Accepted: 01/08/2020] [Indexed: 12/14/2022] Open
Abstract
Cystic fibrosis (CF) is the most common lethal inherited disease among Caucasians in North America and a significant portion of Europe. The disease arises from one of many mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator, or CFTR. The most common disease-associated allele, F508del, along with several other mutations affect the folding, transport, and stability of CFTR as it transits from the endoplasmic reticulum (ER) to the plasma membrane, where it functions primarily as a chloride channel. Early data demonstrated that F508del CFTR is selected for ER associated degradation (ERAD), a pathway in which misfolded proteins are recognized by ER-associated molecular chaperones, ubiquitinated, and delivered to the proteasome for degradation. Later studies showed that F508del CFTR that is rescued from ERAD and folds can alternatively be selected for enhanced endocytosis and lysosomal degradation. A number of other disease-causing mutations in CFTR also undergo these events. Fortunately, pharmacological modulators of CFTR biogenesis can repair CFTR, permitting its folding, escape from ERAD, and function at the cell surface. In this article, we review the many cellular checkpoints that monitor CFTR biogenesis, discuss the emergence of effective treatments for CF, and highlight future areas of research on the proteostatic control of CFTR.
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16
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Yanda MK, Guggino WB, Cebotaru L. A new role for heat shock factor 27 in the pathophysiology of Clostridium difficile toxin B. Am J Physiol Gastrointest Liver Physiol 2020; 318:G120-G129. [PMID: 31709831 PMCID: PMC6985846 DOI: 10.1152/ajpgi.00166.2019] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Clostridiumdifficile (CD) is a common pathogen that causes severe gastrointestinal inflammatory diarrhea in patients undergoing antibiotic therapy. Its virulence derives from two toxins, toxin CD, A and B (TcdA and TcdB) (Borriello et al. Rev Infect Dis 12, Suppl 2: S185-191, 1990). Among the prime candidates for CD colonization are patients with cystic fibrosis (CF), who are routinely treated with antibiotics and frequently hospitalized. Indeed, ~50% of patients with CF are colonized with virulent forms of CD but do not exhibit diarrhea (Bauer et al. Clin Microbiol Infect 20: O446-O449, 2014; Binkovitz et al. Am J Roentgenol 172: 517-521, 199; Zemljic et al. Anaerobe 16: 527-532, 2010). We found that TcdB has global effects on colonic cells, including reducing the steady-state levels of sodium-proton exchange regulatory factors, reducing the levels of heat shock protein (Hsp) 27, and increasing the fraction of total Hsp27 bound to the cystic fibrosis transmembrane conductance regulator (CFTR). Also, since some mutations in CFTR seem to be protective, we asked whether CFTR is a target of TcdB. We show here that TcdB increases the maturation of CFTR and transiently increases its function. These combined effects promote increased surface expression of CFTR, resulting in a transient increase in Cl- secretion. This increase is followed by a precipitous decline in both CFTR-dependent Cl- secretion and transepithelial resistance (TER), suggesting a breakdown in the epithelial cells' tight junctions. We also found that overexpressing Hsp27 reverses some of the deleterious effects of TcdB, in particular preserving TER and therefore likely the maintenance of barrier function. Thus, our data suggest that Hsp27 plays a role in the diarrhea generated by CD infection and is a potential therapeutic target for treating this diarrhea.NEW & NOTEWORTHYClostridium difficile (CD) is a common pathogen that causes severe gastrointestinal inflammatory diarrhea in patients undergoing antibiotic therapy. We provide new evidence that heat shock protein (Hsp) 27 is one of the key players in CD pathology and that increasing Hsp27 can prevent the decrease in transepithelial resistance induced by toxin CD B, pointing the way for pharmacologic therapies for patients with chronic CD infection that can increase Hsp27 as a means to mitigate the effects of CD on gastrointestinal pathology.
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Affiliation(s)
- Murali K. Yanda
- Departments of Medicine and Physiology, Johns Hopkins University, Baltimore, Maryland
| | - William B. Guggino
- Departments of Medicine and Physiology, Johns Hopkins University, Baltimore, Maryland
| | - Liudmila Cebotaru
- Departments of Medicine and Physiology, Johns Hopkins University, Baltimore, Maryland
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17
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Holt GT, Jou JD, Gill NP, Lowegard AU, Martin JW, Madden DR, Donald BR. Computational Analysis of Energy Landscapes Reveals Dynamic Features That Contribute to Binding of Inhibitors to CFTR-Associated Ligand. J Phys Chem B 2019; 123:10441-10455. [PMID: 31697075 DOI: 10.1021/acs.jpcb.9b07278] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The CFTR-associated ligand PDZ domain (CALP) binds to the cystic fibrosis transmembrane conductance regulator (CFTR) and mediates lysosomal degradation of mature CFTR. Inhibition of this interaction has been explored as a therapeutic avenue for cystic fibrosis. Previously, we reported the ensemble-based computational design of a novel peptide inhibitor of CALP, which resulted in the most binding-efficient inhibitor to date. This inhibitor, kCAL01, was designed using osprey and evinced significant biological activity in in vitro cell-based assays. Here, we report a crystal structure of kCAL01 bound to CALP and compare structural features against iCAL36, a previously developed inhibitor of CALP. We compute side-chain energy landscapes for each structure to not only enable approximation of binding thermodynamics but also reveal ensemble features that contribute to the comparatively efficient binding of kCAL01. Finally, we compare the previously reported design ensemble for kCAL01 vs the new crystal structure and show that, despite small differences between the design model and crystal structure, significant biophysical features that enhance inhibitor binding are captured in the design ensemble. This suggests not only that ensemble-based design captured thermodynamically significant features observed in vitro, but also that a design eschewing ensembles would miss the kCAL01 sequence entirely.
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Affiliation(s)
- Graham T Holt
- Department of Computer Science , Duke University , Durham , North Carolina 27708 , United States.,Program in Computational Biology and Bioinformatics , Duke University , Durham , North Carolina 27708 , United States
| | - Jonathan D Jou
- Department of Computer Science , Duke University , Durham , North Carolina 27708 , United States
| | - Nicholas P Gill
- Department of Biochemistry & Cell Biology , Geisel School of Medicine at Dartmouth , Hanover , New Hampshire 03755 , United States
| | - Anna U Lowegard
- Department of Computer Science , Duke University , Durham , North Carolina 27708 , United States.,Program in Computational Biology and Bioinformatics , Duke University , Durham , North Carolina 27708 , United States
| | - Jeffrey W Martin
- Department of Computer Science , Duke University , Durham , North Carolina 27708 , United States
| | - Dean R Madden
- Department of Biochemistry & Cell Biology , Geisel School of Medicine at Dartmouth , Hanover , New Hampshire 03755 , United States
| | - Bruce R Donald
- Department of Computer Science , Duke University , Durham , North Carolina 27708 , United States.,Department of Biochemistry , Duke University , Durham , North Carolina 27710 , United States.,Department of Chemistry , Duke University , Durham , North Carolina 27710 , United States
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18
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Favia M, de Bari L, Bobba A, Atlante A. An Intriguing Involvement of Mitochondria in Cystic Fibrosis. J Clin Med 2019; 8:jcm8111890. [PMID: 31698802 PMCID: PMC6912654 DOI: 10.3390/jcm8111890] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 10/31/2019] [Accepted: 11/04/2019] [Indexed: 12/16/2022] Open
Abstract
Cystic fibrosis (CF) occurs when the cystic fibrosis transmembrane conductance regulator (CFTR) protein is not synthetized and folded correctly. The CFTR protein helps to maintain the balance of salt and water on many body surfaces, such as the lung surface. When the protein is not working correctly, chloride becomes trapped in cells, then water cannot hydrate the cellular surface and the mucus covering the cells becomes thick and sticky. Furthermore, a defective CFTR appears to produce a redox imbalance in epithelial cells and extracellular fluids and to cause an abnormal generation of reactive oxygen species: as a consequence, oxidative stress has been implicated as a causative factor in the aetiology of the process. Moreover, massive evidences show that defective CFTR gives rise to extracellular GSH level decrease and elevated glucose concentrations in airway surface liquid (ASL), thus encouraging lung infection by pathogens in the CF advancement. Recent research in progress aims to rediscover a possible role of mitochondria in CF. Here the latest new and recent studies on mitochondrial bioenergetics are collected. Surprisingly, they have enabled us to ascertain that mitochondria have a leading role in opposing the high ASL glucose level as well as oxidative stress in CF.
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Affiliation(s)
- Maria Favia
- Istituto di Biomembrane, Bioenergetica e Biotecnologie Molecolari—CNR, Via G. Amendola 122/O, 70126 Bari, Italy; (L.d.B.); (A.B.)
- Dipartimento di Bioscienze, Biotecnologie e Biofarmaceutica, Università di Bari, Via E. Orabona 4, 70126 Bari, Italy
- Correspondence: (M.F.); (A.A.)
| | - Lidia de Bari
- Istituto di Biomembrane, Bioenergetica e Biotecnologie Molecolari—CNR, Via G. Amendola 122/O, 70126 Bari, Italy; (L.d.B.); (A.B.)
| | - Antonella Bobba
- Istituto di Biomembrane, Bioenergetica e Biotecnologie Molecolari—CNR, Via G. Amendola 122/O, 70126 Bari, Italy; (L.d.B.); (A.B.)
| | - Anna Atlante
- Istituto di Biomembrane, Bioenergetica e Biotecnologie Molecolari—CNR, Via G. Amendola 122/O, 70126 Bari, Italy; (L.d.B.); (A.B.)
- Correspondence: (M.F.); (A.A.)
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19
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Marklew AJ, Patel W, Moore PJ, Tan CD, Smith AJ, Sassano MF, Gray MA, Tarran R. Cigarette Smoke Exposure Induces Retrograde Trafficking of CFTR to the Endoplasmic Reticulum. Sci Rep 2019; 9:13655. [PMID: 31541117 PMCID: PMC6754399 DOI: 10.1038/s41598-019-49544-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Accepted: 08/12/2019] [Indexed: 12/16/2022] Open
Abstract
Chronic obstructive pulmonary disease (COPD), which is most commonly caused by cigarette smoke (CS) exposure, is the third leading cause of death worldwide. The cystic fibrosis transmembrane conductance regulator (CFTR) is an apical membrane anion channel that is widely expressed in epithelia throughout the body. In the airways, CFTR plays an important role in fluid homeostasis and helps flush mucus and inhaled pathogens/toxicants out of the lung. Inhibition of CFTR leads to mucus stasis and severe airway disease. CS exposure also inhibits CFTR, leading to the decreased anion secretion/hydration seen in COPD patients. However, the underlying mechanism is poorly understood. Here, we report that CS causes CFTR to be internalized in a clathrin/dynamin-dependent fashion. This internalization is followed by retrograde trafficking of CFTR to the endoplasmic reticulum. Although this internalization pathway has been described for bacterial toxins and cargo machinery, it has never been reported for mammalian ion channels. Furthermore, the rapid internalization of CFTR is dependent on CFTR dephosphorylation by calcineurin, a protein phosphatase that is upregulated by CS. These results provide new insights into the mechanism of CFTR internalization, and may help in the development of new therapies for CFTR correction and lung rehydration in patients with debilitating airway diseases such as COPD.
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Affiliation(s)
- Abigail J Marklew
- Marsico Lung Institute, University of North Carolina, Chapel Hill, NC, USA
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle-upon-Tyne, UK
| | - Waseema Patel
- Marsico Lung Institute, University of North Carolina, Chapel Hill, NC, USA
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle-upon-Tyne, UK
| | - Patrick J Moore
- Marsico Lung Institute, University of North Carolina, Chapel Hill, NC, USA
| | - Chong D Tan
- Marsico Lung Institute, University of North Carolina, Chapel Hill, NC, USA
| | - Amanda J Smith
- Marsico Lung Institute, University of North Carolina, Chapel Hill, NC, USA
- Department of Cell Biology & Physiology, University of North Carolina, Chapel Hill, NC, USA
| | - M Flori Sassano
- Marsico Lung Institute, University of North Carolina, Chapel Hill, NC, USA
| | - Michael A Gray
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle-upon-Tyne, UK
| | - Robert Tarran
- Marsico Lung Institute, University of North Carolina, Chapel Hill, NC, USA.
- Department of Cell Biology & Physiology, University of North Carolina, Chapel Hill, NC, USA.
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20
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Liu Q, Sabirzhanova I, Bergbower EAS, Yanda M, Guggino WG, Cebotaru L. The CFTR Corrector, VX-809 (Lumacaftor), Rescues ABCA4 Trafficking Mutants: a Potential Treatment for Stargardt Disease. Cell Physiol Biochem 2019; 53:400-412. [PMID: 31403270 DOI: 10.33594/000000146] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Accepted: 08/08/2019] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND/AIMS Mutations in ABCA4 cause Stargardt macular degeneration, which invariably ends in legal blindness. We studied two common mutants, A1038V (in NBD1) and G1961E (in NBD2), with the purpose of exploring how they interact with the cell's quality control mechanism. The study was designed to determine how these mutants can be rescued. METHODS We expressed wt and mutant ABCA4 in HEK293 cells and studied the effect of the mutations on trafficking and processing and the ability of correctors to rescue them. We used a combination of western blotting, confocal microscopy and surface biotinylation coupled with pulldown of plasma membrane proteins. RESULTS G1961E is sensitive to inhibitors of the aggresome, tubacin and the lysosome, bafilomycin A. Both mutants cause a reduction in heat shock protein, Hsp27. Incubation of HEK293 cells expressing the mutants with VX-809, an FDA approved drug for the treatment of cystic fibrosis, increased the levels of A1038V and G1961E by 2- to 3-fold. Importantly, VX-809 increased the levels of both mutants at the plasma membrane suggesting that trafficking had been restored. Transfecting additional Hsp27 to the cells also increased the steady state levels of both mutants. However, in combination with VX-809 the addition of Hsp27 caused a dramatic increase in the protein expression particularly in the G1961 mutant which increased approximately 5-fold. CONCLUSION Our results provide a new mechanism for the rescue of ABCA4 trafficking mutants based on the restoration of Hsp27. Our results provide a pathway for the treatment of Stargardt disease.
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Affiliation(s)
- Qiangni Liu
- Division of Gastroenterology and Hepatology, Departments of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Inna Sabirzhanova
- Division of Gastroenterology and Hepatology, Departments of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Emily Anne Smith Bergbower
- Division of Gastroenterology and Hepatology, Departments of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Murali Yanda
- Division of Gastroenterology and Hepatology, Departments of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - William G Guggino
- Division of Gastroenterology and Hepatology, Departments of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Liudmila Cebotaru
- Division of Gastroenterology and Hepatology, Departments of Medicine, Johns Hopkins University, Baltimore, MD, USA,
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21
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Yang B, Xue Q, Guo J, Wang X, Zhang Y, Guo K, Li W, Chen S, Xue T, Qi X, Wang J. Autophagy induction by the pathogen receptor NECTIN4 and sustained autophagy contribute to peste des petits ruminants virus infectivity. Autophagy 2019; 16:842-861. [PMID: 31318632 PMCID: PMC7144873 DOI: 10.1080/15548627.2019.1643184] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Macroautophagy/autophagy is an essential cellular response in the fight against intracellular pathogens. Although some viruses can escape from or utilize autophagy to ensure their own replication, the responses of autophagy pathways to viral invasion remain poorly documented. Here, we show that peste des petits ruminants virus (PPRV) infection induces successive autophagic signalling in host cells via distinct and uncoupled molecular pathways. Immediately upon invasion, PPRV induced a first transient wave of autophagy via a mechanism involving the cellular pathogen receptor NECTIN4 and an AKT-MTOR-dependent pathway. Autophagic detection showed that early PPRV infection not only increased the amounts of autophagosomes and LC3-II but also downregulated the phosphorylation of AKT-MTOR. Subsequently, we found that the binding of viral protein H to NECTIN4 ultimately induced a wave of autophagy and inactivated the AKT-MTOR pathway, which is a critical step for the control of infection. Soon after infection, new autophagic signalling was initiated that required viral replication and protein expression. Interestingly, expression of IRGM and HSPA1A was significantly upregulated following PPRV replication. Strikingly, knockdown of IRGM and HSPA1A expression using small interfering RNAs impaired the PPRV-induced second autophagic wave and viral particle production. Moreover, IRGM-interacting PPRV-C and HSPA1A-interacting PPRV-N expression was sufficient to induce autophagy through an IRGM-HSPA1A-dependent pathway. Importantly, syncytia formation could facilitate sustained autophagy and the replication of PPRV. Overall, our work reveals distinct molecular pathways underlying the induction of self-beneficial sustained autophagy by attenuated PPRV, which will contribute to improving the use of vaccines for therapy. Abbreviations: ACTB: actin beta; ANOVA: analysis of variance; ATG: autophagy-related; BECN1: beclin 1; CDV: canine distemper virus; Co-IP: coimmunoprecipitation; FIP: fusion inhibitory peptide; GFP: green fluorescent protein; GST: glutathione S-transferase; HMOX1: heme oxygenase 1; hpi: hours post infection; HSPA1A: heat shock protein family A (Hsp70) member 1A; HSP90AA1: heat shock protein 90 kDa alpha (cytosolic), class A member 1; IFN: interferon; IgG: immunoglobulin G; INS: insulin; IRGM: immunity related GTPase M; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MeV: measles virus; MOI: multiplicity of infection; MTOR: mechanistic target of rapamycin kinase; PI3K: phosphoinositide-3 kinase; PIK3C3: phosphatidylinositol 3-kinase catalytic subunit type 3; SDS: sodium dodecyl sulfate; siRNA: small interfering RNA; SQSTM1/p62: sequestosome 1; UV: ultraviolet.
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Affiliation(s)
- Bo Yang
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Qinghong Xue
- Department of viral biologics, China Institute of Veterinary Drug Control, Beijing, China
| | - Jiaona Guo
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Xueping Wang
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Yanming Zhang
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Kangkang Guo
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Wei Li
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Shuying Chen
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Tianxia Xue
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Xuefeng Qi
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Jingyu Wang
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
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22
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Sasaki S, Sun R, Bui HH, Crosby JR, Monia BP, Guo S. Steric Inhibition of 5' UTR Regulatory Elements Results in Upregulation of Human CFTR. Mol Ther 2019; 27:1749-1757. [PMID: 31351782 PMCID: PMC6822282 DOI: 10.1016/j.ymthe.2019.06.016] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 06/25/2019] [Accepted: 06/28/2019] [Indexed: 12/20/2022] Open
Abstract
Cystic fibrosis (CF) is an autosomal recessive monogenic disease caused by mutations in the CFTR gene. Therapeutic approaches that are focused on correcting CFTR protein face the challenge of the heterogeneity in CFTR mutations and resulting defects. Thus, while several small molecules directed at CFTR show benefit in the clinic for subsets of CF patients, these drugs cannot treat all CF patients. Additionally, the clinical benefit from treatment with these modulators could be enhanced with novel therapies. To address this unmet need, we utilized an approach to increase CFTR protein levels through antisense oligonucleotide (ASO)-mediated steric inhibition of 5′ UTR regulatory elements. We identified ASOs to upregulate CFTR protein expression and confirmed the regulatory role of the sites amenable to ASO-mediated upregulation. Two ASOs were investigated further, and both increased CFTR protein expression and function in cell lines and primary human bronchial epithelial cells with distinct CF genotypes. ASO treatment further increased CFTR function in almost all CF genotypes tested on top of treatment with the FDA approved drug Symdeko (ivacaftor and tezacaftor). Thus, we present a novel approach to CFTR therapeutic intervention, through ASO-mediated modulation of translation.
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Affiliation(s)
- Shruti Sasaki
- Ionis Pharmaceuticals, 2855 Gazelle Court, Carlsbad, CA 92010, USA
| | - Rachel Sun
- University of Michigan, Ann Arbor, 500 S State St., Ann Arbor, MI 48109, USA
| | - Huynh-Hoa Bui
- Ionis Pharmaceuticals, 2855 Gazelle Court, Carlsbad, CA 92010, USA
| | - Jeff R Crosby
- Ionis Pharmaceuticals, 2855 Gazelle Court, Carlsbad, CA 92010, USA
| | - Brett P Monia
- Ionis Pharmaceuticals, 2855 Gazelle Court, Carlsbad, CA 92010, USA
| | - Shuling Guo
- Ionis Pharmaceuticals, 2855 Gazelle Court, Carlsbad, CA 92010, USA.
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23
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Christensen NR, Čalyševa J, Fernandes EFA, Lüchow S, Clemmensen LS, Haugaard‐Kedström LM, Strømgaard K. PDZ Domains as Drug Targets. ADVANCED THERAPEUTICS 2019; 2:1800143. [PMID: 32313833 PMCID: PMC7161847 DOI: 10.1002/adtp.201800143] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 03/25/2019] [Indexed: 12/14/2022]
Abstract
Protein-protein interactions within protein networks shape the human interactome, which often is promoted by specialized protein interaction modules, such as the postsynaptic density-95 (PSD-95), discs-large, zona occludens 1 (ZO-1) (PDZ) domains. PDZ domains play a role in several cellular functions, from cell-cell communication and polarization, to regulation of protein transport and protein metabolism. PDZ domain proteins are also crucial in the formation and stability of protein complexes, establishing an important bridge between extracellular stimuli detected by transmembrane receptors and intracellular responses. PDZ domains have been suggested as promising drug targets in several diseases, ranging from neurological and oncological disorders to viral infections. In this review, the authors describe structural and genetic aspects of PDZ-containing proteins and discuss the current status of the development of small-molecule and peptide modulators of PDZ domains. An overview of potential new therapeutic interventions in PDZ-mediated protein networks is also provided.
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Affiliation(s)
- Nikolaj R. Christensen
- Center for BiopharmaceuticalsDepartment of Drug Design and PharmacologyUniversity of CopenhagenUniversitetsparken 22100CopenhagenDenmark
| | - Jelena Čalyševa
- European Molecular Biology Laboratory (EMBL)Structural and Computational Biology UnitMeyerhofstraße 169117HeidelbergGermany
- EMBL International PhD ProgrammeFaculty of BiosciencesEMBL–Heidelberg UniversityGermany
| | - Eduardo F. A. Fernandes
- Center for BiopharmaceuticalsDepartment of Drug Design and PharmacologyUniversity of CopenhagenUniversitetsparken 22100CopenhagenDenmark
| | - Susanne Lüchow
- Department of Chemistry – BMCUppsala UniversityBox 576SE75123UppsalaSweden
| | - Louise S. Clemmensen
- Center for BiopharmaceuticalsDepartment of Drug Design and PharmacologyUniversity of CopenhagenUniversitetsparken 22100CopenhagenDenmark
| | - Linda M. Haugaard‐Kedström
- Center for BiopharmaceuticalsDepartment of Drug Design and PharmacologyUniversity of CopenhagenUniversitetsparken 22100CopenhagenDenmark
| | - Kristian Strømgaard
- Center for BiopharmaceuticalsDepartment of Drug Design and PharmacologyUniversity of CopenhagenUniversitetsparken 22100CopenhagenDenmark
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24
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Luo WY, Xing SQ, Zhu P, Zhang CG, Yang HM, Van Halm-Lutterodt N, Gu L, Zhang H. PDZ Scaffold Protein CAL Couples with Metabotropic Glutamate Receptor 5 to Protect Against Cell Apoptosis and Is a Potential Target in the Treatment of Parkinson's Disease. Neurotherapeutics 2019; 16:761-783. [PMID: 31073978 PMCID: PMC6694344 DOI: 10.1007/s13311-019-00730-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Targeting mGluR5 has been an attractive strategy to modulate glutamate excitotoxicity for neuroprotection. Although human clinical trials using mGluR5 negative allosteric modulators (NAMs) have included some disappointments, recent investigations have added several more attractive small molecules to this field, providing a promise that the identification of more additional strategies to modulate mGluR5 activity might be potentially beneficial for the advancement of PD treatment. Here, we determined the role of the interacting partner CAL (cystic fibrosis transmembrane conductance regulator-associated ligand) in mGluR5-mediated protection in vitro and in vivo. In astroglial C6 cells, CAL deficiency blocked (S)-3, 5-dihydroxyphenylglycine (DHPG)-elicited p-AKT and p-ERK1/2, subsequently prevented group I mGluRs-mediated anti-apoptotic protection, which was blocked by receptor antagonist 1-aminoindan-1, 5-dicarboxylic acid (AIDA), and PI3K or MEK inhibitor LY294002 or U0126. In rotenone-treated MN9D cells, both CAL and mGluR5 expressions were decreased in a time- and dose-dependent manner, and the correlation between these 2 proteins was confirmed by lentivirus-delivered CAL overexpression and knockdown. Moreover, CAL coupled with mGluR5 upregulated mGluR5 protein expression by inhibition of ubiquitin-proteasome-dependent degradation to suppress mGluR5-mediated p-JNK and to protect against cell apoptosis. Additionally, CAL also inhibited rotenone-induced glutamate release to modulate mGluR5 activity. Furthermore, in the rotenone-induced rat model of PD, AAV-delivered CAL overexpression attenuated behavioral deficits and dopaminergic neuronal death, while CAL deficiency aggravated rotenone toxicity. On the other hand, the protective effect of the mGluR5 antagonist MPEP was weakened by knocking down CAL. In vivo experiments also confirmed that CAL inhibited ubiquitination-proteasome-dependent degradation to modulate mGluR5 expression and JNK phosphorylation. Our findings show that CAL protects against cell apoptosis via modulating mGluR5 activity, and may be a new molecular target for an effective therapeutic strategy for PD.
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Affiliation(s)
- Wen Yuan Luo
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Institute for Brain Disorders and Key Laboratory for Neurodegenerative Disorders of the Ministry of Education, Capital Medical University, Beijing, 100069, China
| | - Su Qian Xing
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Institute for Brain Disorders and Key Laboratory for Neurodegenerative Disorders of the Ministry of Education, Capital Medical University, Beijing, 100069, China
| | - Ping Zhu
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Institute for Brain Disorders and Key Laboratory for Neurodegenerative Disorders of the Ministry of Education, Capital Medical University, Beijing, 100069, China
| | - Chen Guang Zhang
- Department of Biochemistry and Molecular Biology, Capital Medical University, Beijing, 100069, China
| | - Hui Min Yang
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Institute for Brain Disorders and Key Laboratory for Neurodegenerative Disorders of the Ministry of Education, Capital Medical University, Beijing, 100069, China
| | - Nicholas Van Halm-Lutterodt
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100069, China
- Department of Orthopaedics and Neurosurgery, Keck Medical Center, University of Southern California, Los Angeles, CA, 90033, USA
| | - Li Gu
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Institute for Brain Disorders and Key Laboratory for Neurodegenerative Disorders of the Ministry of Education, Capital Medical University, Beijing, 100069, China.
| | - Hong Zhang
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Institute for Brain Disorders and Key Laboratory for Neurodegenerative Disorders of the Ministry of Education, Capital Medical University, Beijing, 100069, China.
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25
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Espiritu EB, Jiang H, Moreau-Marquis S, Sullivan M, Yan K, Beer Stolz D, Sampson MG, Hukriede NA, Swiatecka-Urban A. The human nephrin Y 1139RSL motif is essential for podocyte foot process organization and slit diaphragm formation during glomerular development. J Biol Chem 2019; 294:10773-10788. [PMID: 31152064 DOI: 10.1074/jbc.ra119.008235] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 05/16/2019] [Indexed: 11/06/2022] Open
Abstract
Nephrin is an immunoglobulin-type cell-adhesion molecule with a key role in the glomerular interpodocyte slit diaphragm. Mutations in the nephrin gene are associated with defects in the slit diaphragm, leading to early-onset nephrotic syndrome, typically resistant to treatment. Although the endocytic trafficking of nephrin is essential for the assembly of the slit diaphragm, nephrin's specific endocytic motifs remain unknown. To search for endocytic motifs, here we performed a multisequence alignment of nephrin and identified a canonical YXXØ-type motif, Y1139RSL, in the nephrin cytoplasmic tail, expressed only in primates. Using site-directed mutagenesis, various biochemical methods, single-plane illumination microscopy, a human podocyte line, and a human nephrin-expressing zebrafish model, we found that Y1139RSL is a novel endocytic motif and a structural element for clathrin-mediated nephrin endocytosis that functions as a phosphorylation-sensitive signal. We observed that Y1139RSL motif-mediated endocytosis helps to localize nephrin to specialized plasma membrane domains in podocytes and is essential for normal foot process organization into a functional slit diaphragm between neighboring foot processes in zebrafish. The importance of nephrin Y1139RSL for healthy podocyte development was supported by population-level analyses of genetic variations at this motif, revealing that such variations are very rare, suggesting that mutations in this motif have autosomal-recessive negative effects on kidney health. These findings expand our understanding of the mechanism underlying nephrin endocytosis and may lead to improved diagnostic tools or therapeutic strategies for managing early-onset, treatment-resistant nephrotic syndrome.
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Affiliation(s)
- Eugenel B Espiritu
- Department of Developmental Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15201
| | - Huajun Jiang
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15224
| | - Sophie Moreau-Marquis
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire 03755
| | - Mara Sullivan
- Department of Nephrology, UPMC Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15201
| | - Kunimasa Yan
- Department of Pediatrics, Kyorin University School of Medicine, Mitaka, Tokyo 181-8611, Japan, and
| | - Donna Beer Stolz
- Department of Nephrology, UPMC Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15201
| | - Matthew G Sampson
- Department of Pediatrics-Nephrology University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Neil A Hukriede
- Department of Developmental Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15201
| | - Agnieszka Swiatecka-Urban
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15224,.
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26
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Wakabayashi-Nakao K, Yu Y, Nakakuki M, Hwang TC, Ishiguro H, Sohma Y. Characterization of Δ(G970-T1122)-CFTR, the most frequent CFTR mutant identified in Japanese cystic fibrosis patients. J Physiol Sci 2019; 69:103-112. [PMID: 29951967 PMCID: PMC10717160 DOI: 10.1007/s12576-018-0626-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 06/19/2018] [Indexed: 12/24/2022]
Abstract
A massive deletion over three exons 16-17b in the CFTR gene was identified in Japanese CF patients with the highest frequency (about 70% of Japanese CF patients definitely diagnosed). This pathogenic mutation results in a deletion of 153 amino acids from glycine at position 970 (G970) to threonine at 1122 (T1122) in the CFTR protein without a frameshift. We name it Δ(G970-T1122)-CFTR. In the present study, we characterized the Δ(G970-T1122)-CFTR expressed in CHO cells using immunoblots and a super resolution microscopy. Δ(G970-T1122)-CFTR proteins were synthesized and core-glycosylated but not complex-glycosylated. This observation suggests that the Δ(G970-T1122) mutation can be categorized into the class II mutation like ΔF508. However, VX-809 a CFTR corrector that can help maturation of ΔF508, had no effect on Δ(G970-T1122). Interestingly C-terminal FLAG tag seems to partially rescue the trafficking defect of Δ(G970-T1122)-CFTR; however the rescued Δ(G970-T1122)-CFTR proteins do not assume channel function. Japanese, and perhaps people in other Asian nations, carry a class II mutation Δ(G970-T1122) with a higher frequency than previously appreciated. Further study of the Δ(G970-T1122)-CFTR is essential for understanding CF and CFTR-related diseases particularly in Asian countries.
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Affiliation(s)
- Kanako Wakabayashi-Nakao
- Department of Pharmaceutical Sciences and Center for Medical Sciences, International University of Health and Welfare, 2600-1 Kitakanemaru, Otawara, Tochigi, 324-8501, Japan
- Department of Pharmacology, Keio University School of Medicine, Tokyo, Japan
| | - Yingchun Yu
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, 65211, USA
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, 65211, USA
| | - Miyuki Nakakuki
- Department of Human Nutrition, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Tzyh-Chang Hwang
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, 65211, USA
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, 65211, USA
| | - Hiroshi Ishiguro
- Department of Human Nutrition, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yoshiro Sohma
- Department of Pharmaceutical Sciences and Center for Medical Sciences, International University of Health and Welfare, 2600-1 Kitakanemaru, Otawara, Tochigi, 324-8501, Japan.
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, 65211, USA.
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, 65211, USA.
- Department of Pharmacology, Keio University School of Medicine, Tokyo, Japan.
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27
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Liu X, Fuentes EJ. Emerging Themes in PDZ Domain Signaling: Structure, Function, and Inhibition. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2019; 343:129-218. [PMID: 30712672 PMCID: PMC7185565 DOI: 10.1016/bs.ircmb.2018.05.013] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Post-synaptic density-95, disks-large and zonula occludens-1 (PDZ) domains are small globular protein-protein interaction domains widely conserved from yeast to humans. They are composed of ∼90 amino acids and form a classical two α-helical/six β-strand structure. The prototypical ligand is the C-terminus of partner proteins; however, they also bind internal peptide sequences. Recent findings indicate that PDZ domains also bind phosphatidylinositides and cholesterol. Through their ligand interactions, PDZ domain proteins are critical for cellular trafficking and the surface retention of various ion channels. In addition, PDZ proteins are essential for neuronal signaling, memory, and learning. PDZ proteins also contribute to cytoskeletal dynamics by mediating interactions critical for maintaining cell-cell junctions, cell polarity, and cell migration. Given their important biological roles, it is not surprising that their dysfunction can lead to multiple disease states. As such, PDZ domain-containing proteins have emerged as potential targets for the development of small molecular inhibitors as therapeutic agents. Recent data suggest that the critical binding function of PDZ domains in cell signaling is more than just glue, and their binding function can be regulated by phosphorylation or allosterically by other binding partners. These studies also provide a wealth of structural and biophysical data that are beginning to reveal the physical features that endow this small modular domain with a central role in cell signaling.
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Affiliation(s)
- Xu Liu
- Department of Biochemistry, University of Iowa, Iowa City, IA, United States
| | - Ernesto J. Fuentes
- Department of Biochemistry, University of Iowa, Iowa City, IA, United States
- Holden Comprehensive Cancer Center, University of Iowa, Iowa City, IA, United States
- Corresponding author: E-mail:
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28
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Fukuda R, Okiyoneda T. Peripheral Protein Quality Control as a Novel Drug Target for CFTR Stabilizer. Front Pharmacol 2018; 9:1100. [PMID: 30319426 PMCID: PMC6170605 DOI: 10.3389/fphar.2018.01100] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 09/10/2018] [Indexed: 12/12/2022] Open
Abstract
Conformationally defective cystic fibrosis transmembrane conductance regulator (CFTR) including rescued ΔF508-CFTR is rapidly eliminated from the plasma membrane (PM) even in the presence of a CFTR corrector and potentiator, limiting the therapeutic effort of the combination therapy. CFTR elimination from the PM is determined by the conformation-dependent ubiquitination as a part of the peripheral quality control (PQC) mechanism. Recently, the molecular machineries responsible for the CFTR PQC mechanism which includes molecular chaperones and ubiquitination enzymes have been revealed. This review summarizes the molecular mechanism of the CFTR PQC and discusses the possibility that the peripheral ubiquitination mechanism becomes a novel drug target to develop the CFTR stabilizer as a novel class of CFTR modulator.
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Affiliation(s)
- Ryosuke Fukuda
- Department of Biomedical Chemistry, School of Science and Technology, Kwansei Gakuin University, Nishinomiya, Japan
| | - Tsukasa Okiyoneda
- Department of Biomedical Chemistry, School of Science and Technology, Kwansei Gakuin University, Nishinomiya, Japan
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29
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Thomas A, Ramananda Y, Mun K, Naren AP, Arora K. AC6 is the major adenylate cyclase forming a diarrheagenic protein complex with cystic fibrosis transmembrane conductance regulator in cholera. J Biol Chem 2018; 293:12949-12959. [PMID: 29903911 DOI: 10.1074/jbc.ra118.003378] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 05/29/2018] [Indexed: 01/08/2023] Open
Abstract
The World Health Organization(WHO) has reported a worldwide surge in cases of cholera caused by the intestinal pathogen Vibrio cholerae, and, combined, such surges have claimed several million lives, mostly in early childhood. Elevated cAMP production in intestinal epithelial cells challenged with cholera toxin (CTX) results in diarrhea due to chloride transport by a cAMP-activated channel, the cystic fibrosis transmembrane conductance regulator (CFTR). However, the identity of the main cAMP-producing proteins that regulate CFTR in the intestine and may be relevant for secretory diarrhea is unclear. Here, using RNA-Seq to identify the predominant AC isoform in mouse and human cells and extensive biochemical analyses for further characterization, we found that the cAMP-generating enzyme adenylate cyclase 6 (AC6) physically and functionally associates with CFTR at the apical surface of intestinal epithelial cells. We generated epithelium-specific AC6 knockout mice and demonstrated that CFTR-dependent fluid secretion is nearly abolished in AC6 knockout mice upon CTX challenge in ligated ileal loops. Furthermore, loss of AC6 function dramatically impaired CTX-induced CFTR activation in human and mouse intestinal spheroids. Our finding that the CFTR-AC6 protein complex is the key mediator of CTX-associated diarrhea may facilitate development of antidiarrheal agents to manage cholera symptoms and improve outcomes.
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Affiliation(s)
- Andrew Thomas
- Division of Pulmonary Medicine, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229
| | - Yashaswini Ramananda
- Division of Pulmonary Medicine, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229; Department of Biomedical Sciences, University of Illinois, Chicago, Illinois 60607
| | - KyuShik Mun
- Division of Pulmonary Medicine, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229
| | - Anjaparavanda P Naren
- Division of Pulmonary Medicine, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229.
| | - Kavisha Arora
- Division of Pulmonary Medicine, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229.
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30
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Bergbower E, Boinot C, Sabirzhanova I, Guggino W, Cebotaru L. The CFTR-Associated Ligand Arrests the Trafficking of the Mutant ΔF508 CFTR Channel in the ER Contributing to Cystic Fibrosis. Cell Physiol Biochem 2018; 45:639-655. [PMID: 29402832 DOI: 10.1159/000487120] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 11/01/2017] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND/AIMS The CFTR-Associated Ligand (CAL), a PDZ domain containing protein with two coiled-coil domains, reduces cell surface WT CFTR through degradation in the lysosome by a well-characterized mechanism. However, CAL's regulatory effect on ΔF508 CFTR has remained almost entirely uninvestigated. METHODS In this study, we describe a previously unknown pathway for CAL by which it regulates the membrane expression of ΔF508 CFTR through arrest of ΔF508 CFTR trafficking in the endoplasmic reticulum (ER) using a combination of cell biology, biochemistry and electrophysiology. RESULTS We demonstrate that CAL is an ER localized protein that binds to ΔF508 CFTR and is degraded in the 26S proteasome. When CAL is inhibited, ΔF508 CFTR retention in the ER decreases and cell surface expression of mature functional ΔF508 CFTR is observed alongside of enhanced expression of plasma membrane scaffolding protein NHERF1. Chaperone proteins regulate this novel process, and ΔF508 CFTR binding to HSP40, HSP90, HSP70, VCP, and Aha1 changes to improve ΔF508 CFTR cell surface trafficking. CONCLUSION Our results reveal a pathway in which CAL regulates the cell surface availability and intracellular retention of ΔF508 CFTR.
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Affiliation(s)
- Emily Bergbower
- The Graduate Training Program in Cellular and Molecular Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Department of Gastroenterology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Clement Boinot
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Department of Gastroenterology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Inna Sabirzhanova
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Department of Gastroenterology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - William Guggino
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Department of Gastroenterology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Liudmila Cebotaru
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Department of Gastroenterology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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31
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Okamoto CT. Regulation of Transporters and Channels by Membrane-Trafficking Complexes in Epithelial Cells. Cold Spring Harb Perspect Biol 2017; 9:a027839. [PMID: 28246186 PMCID: PMC5666629 DOI: 10.1101/cshperspect.a027839] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The vectorial secretion and absorption of fluid and solutes by epithelial cells is dependent on the polarized expression of membrane solute transporters and channels at the apical and basolateral membranes. The establishment and maintenance of this polarized expression of transporters and channels are affected by divers protein-trafficking complexes. Moreover, regulation of the magnitude of transport is often under control of physiological stimuli, again through the interaction of transporters and channels with protein-trafficking complexes. This review highlights the value in utilizing transporters and channels as cargo to characterize core trafficking machinery by which epithelial cells establish and maintain their polarized expression, and how this machinery regulates fluid and solute transport in response to physiological stimuli.
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Affiliation(s)
- Curtis T Okamoto
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California 90089-9121
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32
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Stauffer BB, Cui G, Cottrill KA, Infield DT, McCarty NA. Bacterial Sphingomyelinase is a State-Dependent Inhibitor of the Cystic Fibrosis Transmembrane conductance Regulator (CFTR). Sci Rep 2017; 7:2931. [PMID: 28592822 PMCID: PMC5462758 DOI: 10.1038/s41598-017-03103-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Accepted: 04/24/2017] [Indexed: 02/07/2023] Open
Abstract
Sphingomyelinase C (SMase) inhibits CFTR chloride channel activity in multiple cell systems, an effect that could exacerbate disease in CF and COPD patients. The mechanism by which sphingomyelin catalysis inhibits CFTR is not known but evidence suggests that it occurs independently of CFTR's regulatory "R" domain. In this study we utilized the Xenopus oocyte expression system to shed light on how CFTR channel activity is reduced by SMase. We found that the pathway leading to inhibition is not membrane delimited and that inhibited CFTR channels remain at the cell membrane, indicative of a novel silencing mechanism. Consistent with an effect on CFTR gating behavior, we found that altering gating kinetics influenced the sensitivity to inhibition by SMase. Specifically, increasing channel activity by introducing the mutation K1250A or pretreating with the CFTR potentiator VX-770 (Ivacaftor) imparted resistance to inhibition. In primary bronchial epithelial cells, we found that basolateral, but not apical, application of SMase leads to a redistribution of sphingomyelin and a reduction in forskolin- and VX-770-stimulated currents. Taken together, these data suggest that SMase inhibits CFTR channel function by locking channels into a closed state and that endogenous CFTR in HBEs is affected by SMase activity.
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Affiliation(s)
- B B Stauffer
- Division of Pulmonology, Allergy/Immunology, Cystic Fibrosis, and Sleep, Department of Pediatrics, Emory + Children's Center for Cystic Fibrosis and Airways Disease Research, Emory University School of Medicine and Children's Healthcare of Atlanta, 2015 Uppergate Drive, Atlanta, GA, 30322, USA
- Molecular and Systems Pharmacology program, Emory University, 201 Dowman Drive, Atlanta, GA, 20322, USA
| | - G Cui
- Division of Pulmonology, Allergy/Immunology, Cystic Fibrosis, and Sleep, Department of Pediatrics, Emory + Children's Center for Cystic Fibrosis and Airways Disease Research, Emory University School of Medicine and Children's Healthcare of Atlanta, 2015 Uppergate Drive, Atlanta, GA, 30322, USA
| | - K A Cottrill
- Molecular and Systems Pharmacology program, Emory University, 201 Dowman Drive, Atlanta, GA, 20322, USA
| | - D T Infield
- Division of Pulmonology, Allergy/Immunology, Cystic Fibrosis, and Sleep, Department of Pediatrics, Emory + Children's Center for Cystic Fibrosis and Airways Disease Research, Emory University School of Medicine and Children's Healthcare of Atlanta, 2015 Uppergate Drive, Atlanta, GA, 30322, USA
| | - N A McCarty
- Division of Pulmonology, Allergy/Immunology, Cystic Fibrosis, and Sleep, Department of Pediatrics, Emory + Children's Center for Cystic Fibrosis and Airways Disease Research, Emory University School of Medicine and Children's Healthcare of Atlanta, 2015 Uppergate Drive, Atlanta, GA, 30322, USA.
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33
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Bertrand CA, Mitra S, Mishra SK, Wang X, Zhao Y, Pilewski JM, Madden DR, Frizzell RA. The CFTR trafficking mutation F508del inhibits the constitutive activity of SLC26A9. Am J Physiol Lung Cell Mol Physiol 2017; 312:L912-L925. [PMID: 28360110 PMCID: PMC5495941 DOI: 10.1152/ajplung.00178.2016] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 03/22/2017] [Accepted: 03/22/2017] [Indexed: 11/22/2022] Open
Abstract
Several members of the SLC26A family of anion transporters associate with CFTR, forming complexes in which CFTR and SLC26A functions are reciprocally regulated. These associations are thought to be facilitated by PDZ scaffolding interactions. CFTR has been shown to be positively regulated by NHERF-1, and negatively regulated by CAL in airway epithelia. However, it is unclear which PDZ-domain protein(s) interact with SLC26A9, a SLC26A family member found in airway epithelia. We have previously shown that primary, human bronchial epithelia (HBE) from non-CF donors exhibit constitutive anion secretion attributable to SLC26A9. However, constitutive anion secretion is absent in HBE from CF donors. We examined whether changes in SLC26A9 constitutive activity could be attributed to a loss of CFTR trafficking, and what role PDZ interactions played. HEK293 coexpressing SLC26A9 with the trafficking mutant F508del CFTR exhibited a significant reduction in constitutive current compared with cells coexpressing SLC26A9 and wt CFTR. We found that SLC26A9 exhibits complex glycosylation when coexpressed with F508del CFTR, but its expression at the plasma membrane is decreased. SLC26A9 interacted with both NHERF-1 and CAL, and its interaction with both significantly increased with coexpression of wt CFTR. However, coexpression with F508del CFTR only increased SLC26A9's interaction with CAL. Mutation of SLC26A9's PDZ motif decreased this association with CAL, and restored its constitutive activity. Correcting aberrant F508del CFTR trafficking in CF HBE with corrector VX-809 also restored SLC26A9 activity. We conclude that when SLC26A9 is coexpressed with F508del CFTR, its trafficking defect leads to a PDZ motif-sensitive intracellular retention of SLC26A9.
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Affiliation(s)
- Carol A Bertrand
- Departments of Pediatrics and Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania;
| | - Shalini Mitra
- Departments of Pediatrics and Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Sanjay K Mishra
- Departments of Pediatrics and Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Xiaohui Wang
- Departments of Pediatrics and Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Yu Zhao
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire
| | - Joseph M Pilewski
- Department of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania; and
| | - Dean R Madden
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire
| | - Raymond A Frizzell
- Departments of Pediatrics and Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
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34
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Huang W, Jin A, Zhang J, Wang C, Tsang LL, Cai Z, Zhou X, Chen H, Chan HC. Upregulation of CFTR in patients with endometriosis and its involvement in NFκB-uPAR dependent cell migration. Oncotarget 2017; 8:66951-66959. [PMID: 28978008 PMCID: PMC5620148 DOI: 10.18632/oncotarget.16441] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 03/02/2017] [Indexed: 02/06/2023] Open
Abstract
Endometriotic tissues exhibit high migration ability with the underlying mechanisms remain elusive. Our previous studies have demonstrated that cystic fibrosis transmembrane conductance regulator (CFTR) acts as a tumor suppressor regulating cell migration. In the present study, we explored whether CFTR plays a role in the development of human endometriosis. We found that both mRNA and protein expression levels of CFTR and urokinase-type plasminogen activator receptor (uPAR) were significantly increased in ectopic endometrial tissues from patients with endometriosis compared to normal endometrial tissues from women without endometriosis and positively correlated. In human endometrial Ishikawa (ISK) cells, overexpression of CFTR stimulated cell migration with upregulated NFκB p65 and uPAR. Knockdown of CFTR inhibited cell migration. Furthermore, inhibition of NFκB with its inhibitors (curcumin or Bay) significantly reduced the expression of uPAR and cell migration in the CFTR-overexpressing ISK cells. Collectively, the present results suggest that the CFTR-NFκB-uPAR signaling may contribute to the progression of human endometriosis, and indicate potential targets for diagnosis and treatment.
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Affiliation(s)
- Wenqing Huang
- Epithelial Cell Biology Research Center, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, PR China.,Institute of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, PR China
| | - Aihong Jin
- Department of Gynecology, The Second People's Hospital of Shenzhen, Shenzhen, PR China
| | - Jieting Zhang
- Epithelial Cell Biology Research Center, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, PR China.,Institute of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, PR China
| | - Chaoqun Wang
- Epithelial Cell Biology Research Center, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, PR China.,Institute of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, PR China
| | - Lai Ling Tsang
- Epithelial Cell Biology Research Center, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, PR China.,Institute of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, PR China
| | - Zhiming Cai
- Department of Gynecology, The Second People's Hospital of Shenzhen, Shenzhen, PR China
| | - Xiaping Zhou
- Department of Gynecology, The Second People's Hospital of Shenzhen, Shenzhen, PR China
| | - Hao Chen
- Epithelial Cell Biology Research Center, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, PR China.,Institute of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, PR China
| | - Hsiao Chang Chan
- Epithelial Cell Biology Research Center, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, PR China.,Institute of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, PR China.,Sichuan University - The Chinese University of Hong Kong Joint Laboratory for Reproductive Medicine, West China Second Hospital, Sichuan University, Chengdu, PR China
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Farinha CM, Canato S. From the endoplasmic reticulum to the plasma membrane: mechanisms of CFTR folding and trafficking. Cell Mol Life Sci 2017; 74:39-55. [PMID: 27699454 PMCID: PMC11107782 DOI: 10.1007/s00018-016-2387-7] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 09/28/2016] [Indexed: 01/10/2023]
Abstract
CFTR biogenesis starts with its co-translational insertion into the membrane of endoplasmic reticulum and folding of the cytosolic domains, towards the acquisition of a fully folded compact native structure. Efficiency of this process is assessed by the ER quality control system that allows the exit of folded proteins but targets unfolded/misfolded CFTR to degradation. If allowed to leave the ER, CFTR is modified at the Golgi and reaches the post-Golgi compartments to be delivered to the plasma membrane where it functions as a cAMP- and phosphorylation-regulated chloride/bicarbonate channel. CFTR residence at the membrane is a balance of membrane delivery, endocytosis, and recycling. Several adaptors, motor, and scaffold proteins contribute to the regulation of CFTR stability and are involved in continuously assessing its structure through peripheral quality control systems. Regulation of CFTR biogenesis and traffic (and its dysregulation by mutations, such as the most common F508del) determine its overall activity and thus contribute to the fine modulation of chloride secretion and hydration of epithelial surfaces. This review covers old and recent knowledge on CFTR folding and trafficking from its synthesis to the regulation of its stability at the plasma membrane and highlights how several of these steps can be modulated to promote the rescue of mutant CFTR.
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Affiliation(s)
- Carlos M Farinha
- BioISI-Biosystems and Integrative Sciences Institute, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016, Lisbon, Portugal.
| | - Sara Canato
- BioISI-Biosystems and Integrative Sciences Institute, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016, Lisbon, Portugal
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36
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Wang H, Cebotaru L, Lee HW, Yang Q, Pollard BS, Pollard HB, Guggino WB. CFTR Controls the Activity of NF-κB by Enhancing the Degradation of TRADD. Cell Physiol Biochem 2016; 40:1063-1078. [PMID: 27960153 DOI: 10.1159/000453162] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/11/2016] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND/AIMS Chronic lung infection in cystic fibrosis leads to an inflammatory response that persists because of the chronic presence of bacteria and ultimately leads to a catastrophic failure of lung function. METHODS We use a combination of biochemistry, cell and molecular biology to study the interaction of TRADD, a key adaptor molecule in TNFα signaling, with CFTR in the regulation of NFκB. RESULTS We show that Wt CFTR binds to and colocalizes with TRADD. TRADD is a key signaling intermediate connecting TNFα with activation of NFκB. By contrast, ΔF508 CFTR does not bind to TRADD. NF-κB activation is higher in CFBE expressing ΔF508 CFTR than in cells expressing Wt CFTR. However, this differential effect is abolished when TRADD levels are knocked down. Transfecting Wt CFTR into CFBE cells reduces NF-κB activity. However the reduction is abolished by the CFTR chloride transport inhibitor-172. Consistently, transfecting in the correctly trafficked CFTR conduction mutants G551D or S341A also fail to reduce NFκB activity. Thus CFTR must be functional if it is to regulate NF-κB activity. We also found that TNFα produced a greater increase in NF-κB activity in CFBE cells than in the same cell when Wt CFTR-corrected. Consistently, the effect is also abolished when TRADD is knocked down by shRNA. Thus, Wt CFTR control of TRADD modulates the physiological activation of NF-κB by TNFα. Based on studies with proteosomal and lysosomal inhibitors, the mechanism by which Wt CFTR, but not ΔF508 CFTR, suppresses TRADD is by lysosomal degradation. CONCLUSION We have uncovered a novel mechanism whereby Wt CFTR regulates TNFα signaling by enhancing TRADD degradation. Thus by reducing the levels of TRADD, Wt CFTR suppresses downstream proinflammatory NFκB signaling. By contrast, suppression of NF-κB activation fails in CF cells expressing ΔF508 CFTR.
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Affiliation(s)
- Hua Wang
- Department of Physiology, Medicine, School of Medicine, The Johns Hopkins University, Baltimore, USA
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37
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Li M, Soroka CJ, Harry K, Boyer JL. CFTR-associated ligand is a negative regulator of Mrp2 expression. Am J Physiol Cell Physiol 2016; 312:C40-C46. [PMID: 27834195 DOI: 10.1152/ajpcell.00100.2016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 11/03/2016] [Indexed: 01/15/2023]
Abstract
The multidrug resistance-associated protein 2 (Mrp2) is an ATP-binding cassette transporter that transports a wide variety of organic anions across the apical membrane of epithelial cells. The expression of Mrp2 on the plasma membrane is regulated by protein-protein interactions. Cystic fibrosis transmembrane conductance regulator (CFTR)-associated ligand (CAL) interacts with transmembrane proteins via its PDZ domain and reduces their cell surface expression by increasing lysosomal degradation and intracellular retention. Our results showed that CAL is localized at the trans-Golgi network of rat hepatocytes. The expression of CAL is increased, and Mrp2 expression is decreased, in the liver of mice deficient in sodium/hydrogen exchanger regulatory factor-1. To determine whether CAL interacts with Mrp2 and is involved in the posttranscriptional regulation of Mrp2, we used glutathione S-transferase (GST) fusion proteins with or without the COOH-terminal PDZ binding motif of Mrp2 as the bait in GST pull-down assays. We demonstrated that Mrp2 binds to CAL via its COOH-terminal PDZ-binding motif in GST pull-down assays, an interaction verified by coimmunoprecipitation of these two proteins in cotransfected COS-7 cells. In COS-7 and LLC-PK1 cells transfected with Mrp2 alone, only a mature, high-molecular-mass band of Mrp2 was detected. However, when cells were cotransfected with Mrp2 and CAL, Mrp2 was expressed as both mature and immature forms. Biotinylation and streptavidin pull-down assays confirmed that CAL dramatically reduces the expression level of total and cell surface Mrp2 in Huh-7 cells. Our findings suggest that CAL interacts with Mrp2 and is a negative regulator of Mrp2 expression.
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Affiliation(s)
- Man Li
- The Yale Liver Center, Yale University School of Medicine, New Haven, Connecticut
| | - Carol J Soroka
- The Yale Liver Center, Yale University School of Medicine, New Haven, Connecticut
| | - Kathy Harry
- The Yale Liver Center, Yale University School of Medicine, New Haven, Connecticut
| | - James L Boyer
- The Yale Liver Center, Yale University School of Medicine, New Haven, Connecticut
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38
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Bali V, Lazrak A, Guroji P, Matalon S, Bebok Z. Mechanistic Approaches to Improve Correction of the Most Common Disease-Causing Mutation in Cystic Fibrosis. PLoS One 2016; 11:e0155882. [PMID: 27214033 PMCID: PMC4877091 DOI: 10.1371/journal.pone.0155882] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 05/05/2016] [Indexed: 12/28/2022] Open
Abstract
The most common mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene leads to deletion of the phenylalanine at position 508 (ΔF508) in the CFTR protein and causes multiple folding and functional defects. Contrary to large-scale efforts by industry and academia, no significant therapeutic benefit has been achieved with a single “corrector”. Therefore, investigations concentrate on drug combinations. Orkambi (Vertex Pharmaceuticals), the first FDA-approved drug for treatment of cystic fibrosis (CF) caused by this mutation, is a combination of a corrector (VX-809) that facilitates ΔF508 CFTR biogenesis and a potentiator (VX-770), which improves its function. Yet, clinical trials utilizing this combination showed only modest therapeutic benefit. The low efficacy Orkambi has been attributed to VX-770-mediated destabilization of VX-809-rescued ΔF508 CFTR. Here we report that the negative effects of VX-770 can be reversed by increasing the half-life of the endoplasmic reticulum (ER) form (band B) of ΔF508 CFTR with another corrector (Corr-4a.) Although Corr-4a alone has only minimal effects on ΔF508 CFTR rescue, it increases the half-life of ΔF508 CFTR band B when it is present during half-life measurements. Our data shows that stabilization of band B ΔF508 CFTR with Corr-4a and simultaneous rescue with VX-809, leads to a >2-fold increase in cAMP-activated, CFTRinh-172-inhibited currents compared to VX-809 alone, or VX-809+VX-770. The negative effects of VX-770 and the Corr-4a protection are specific to the native I507-ATT ΔF508 CFTR without affecting the inherently more stable, synonymous variant I507-ATC ΔF508 CFTR. Our studies emphasize that stabilization of ΔF508 CFTR band B in the ER might improve its functional rescue by Orkambi.
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Affiliation(s)
- Vedrana Bali
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Ahmed Lazrak
- Department of Anesthesiology and Perioperative Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- The Lung Injury and Repair Research Center, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Purushotham Guroji
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- The Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Sadis Matalon
- Department of Anesthesiology and Perioperative Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- The Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- The Lung Injury and Repair Research Center, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Zsuzsanna Bebok
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- The Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- The Lung Injury and Repair Research Center, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- * E-mail:
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39
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Rymut SM, Ivy T, Corey DA, Cotton CU, Burgess JD, Kelley TJ. Role of Exchange Protein Activated by cAMP 1 in Regulating Rates of Microtubule Formation in Cystic Fibrosis Epithelial Cells. Am J Respir Cell Mol Biol 2016; 53:853-62. [PMID: 25955407 DOI: 10.1165/rcmb.2014-0462oc] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The regulation of microtubule dynamics in cystic fibrosis (CF) epithelial cells and the consequences of reduced rates of microtubule polymerization on downstream CF cellular events, such as cholesterol accumulation, a marker of impaired intracellular transport, are explored here. It is identified that microtubules in both CF cell models and in primary CF nasal epithelial cells repolymerize at a slower rate compared with respective controls. Previous studies suggest a role for cAMP in modulating organelle transport in CF cells, implicating a role for exchange protein activated by cAMP (EPAC) 1, a regulator of microtubule elongation, as a potential mechanism. EPAC1 activity is reduced in CF cell models and in Cftr(-/-) mouse lung compared with respective non-CF controls. Stimulation of EPAC1 activity with the selective EPAC1 agonist, 8-cpt-2-O-Me-cAMP, stimulates microtubule repolymerization to wild-type rates in CF cells. EPAC1 activation also alleviates cholesterol accumulation in CF cells, suggesting a direct link between microtubule regulation and intracellular transport. To verify the relationship between transport and microtubule regulation, expression of the protein, tubulin polymerization-promoting protein, was knocked down in non-CF human tracheal (9/HTEo(-)) cells to mimic the microtubule dysregulation in CF cells. Transduced cells with short hairpin RNA targeting tubulin polymerization-promoting protein exhibit CF-like perinuclear cholesterol accumulation and other cellular manifestations of CF cells, thus supporting a role for microtubule regulation as a mechanism linking CFTR function to downstream cellular manifestation.
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Affiliation(s)
| | | | | | | | - James D Burgess
- 3 Chemistry, Case Western Reserve University, Cleveland, Ohio
| | - Thomas J Kelley
- Departments of 1 Pharmacology.,2 Pediatrics, and.,3 Chemistry, Case Western Reserve University, Cleveland, Ohio
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40
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Farinha CM, Matos P. Repairing the basic defect in cystic fibrosis - one approach is not enough. FEBS J 2015; 283:246-64. [PMID: 26416076 DOI: 10.1111/febs.13531] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Revised: 09/21/2015] [Accepted: 09/23/2015] [Indexed: 12/16/2022]
Abstract
Cystic fibrosis has attracted much attention in recent years due to significant advances in the pharmacological targeting of the basic defect underlying this recessive disorder: the deficient functional expression of mutant cystic fibrosis transmembrane conductance regulator (CFTR) chloride channels at the apical membrane of epithelial cells. However, increasing evidence points to the reduced efficacy of single treatments, thus reinforcing the need to combine several therapeutic strategies to effectively target the multiple basic defect(s). Protein-repair therapies that use potentiators (activating membrane-located CFTR) or correctors (promoting the relocation of intracellular-retained trafficking mutants of CFTR) in frequent mutations such as F508del and G551D have been put forward and made their way to the clinic with moderate to good efficiency. However, alternative (or additional) approaches targeting the membrane stability of mutant proteins, or correcting the cellular phenotype through a direct effect upon other ion channels (affecting the overall electrolyte transport or simply promoting alternative chloride transport) or targeting less frequent mutations (splicing variants, for example), have been proposed and tested in the field of cystic fibrosis (CF). Here, we cover the different strategies that rely on novel findings concerning the CFTR interactome and signalosome through which it might be possible to further influence the cellular trafficking and post-translational modification machinery (to increase rescued CFTR abundance and membrane stability). We also highlight the new data on strategies aiming at the regulation of sodium absorption or to increase chloride transport through alternative channels. The development and implementation of these complementary approaches will pave the way to combinatorial therapeutic strategies with increased benefit to CF patients.
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Affiliation(s)
- Carlos M Farinha
- BioISI - Biosystems & Integrative Sciences Institute, Faculty of Sciences, University of Lisboa, Portugal
| | - Paulo Matos
- BioISI - Biosystems & Integrative Sciences Institute, Faculty of Sciences, University of Lisboa, Portugal.,Department of Human Genetics, National Health Institute 'Dr. Ricardo Jorge', Lisboa, Portugal
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41
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Sabirzhanova I, Lopes Pacheco M, Rapino D, Grover R, Handa JT, Guggino WB, Cebotaru L. Rescuing Trafficking Mutants of the ATP-binding Cassette Protein, ABCA4, with Small Molecule Correctors as a Treatment for Stargardt Eye Disease. J Biol Chem 2015; 290:19743-55. [PMID: 26092729 DOI: 10.1074/jbc.m115.647685] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Indexed: 11/06/2022] Open
Abstract
Stargardt disease is the most common form of early onset macular degeneration. Mutations in ABCA4, a member of the ATP-binding cassette (ABC) family, are associated with Stargardt disease. Here, we have examined two disease-causing mutations in the NBD1 region of ABCA4, R1108C, and R1129C, which occur within regions of high similarity with CFTR, another ABC transporter gene, which is associated with cystic fibrosis. We show that R1108C and R1129C are both temperature-sensitive processing mutants that engage the cellular quality control mechanism and show a strong interaction with the chaperone Hsp 27. Both mutant proteins also interact with HDCAC6 and are degraded in the aggresome. We also demonstrate that novel corrector compounds that are being tested as treatment for cystic fibrosis, such as VX-809, can rescue the processing of the ABCA4 mutants, particularly their expression at the cell surface, and can reduce their binding to HDAC6. Thus, our data suggest that VX-809 can potentially be developed as a new therapy for Stargardt disease, for which there is currently no treatment.
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Affiliation(s)
- Inna Sabirzhanova
- From the Division of Gastroenterology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland 21205, Physiology Center for Retinal Biology, and
| | - Miquéias Lopes Pacheco
- From the Division of Gastroenterology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland 21205, Physiology Center for Retinal Biology, and
| | - Daniele Rapino
- From the Division of Gastroenterology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland 21205, Physiology Center for Retinal Biology, and
| | - Rahul Grover
- From the Division of Gastroenterology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland 21205, Physiology Center for Retinal Biology, and
| | - James T Handa
- Department of Ophthalmology, Johns Hopkins University, Baltimore, Maryland 21231
| | - William B Guggino
- From the Division of Gastroenterology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland 21205
| | - Liudmila Cebotaru
- From the Division of Gastroenterology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland 21205, Physiology Center for Retinal Biology, and Department of Ophthalmology, Johns Hopkins University, Baltimore, Maryland 21231
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42
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Yang L, Zheng J, Xiong Y, Meng R, Ma Q, Liu H, Shen H, Zheng S, Wang S, He J. Regulation of β2-adrenergic receptor cell surface expression by interaction with cystic fibrosis transmembrane conductance regulator-associated ligand (CAL). Amino Acids 2015; 47:1455-64. [PMID: 25876703 DOI: 10.1007/s00726-015-1965-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2014] [Accepted: 03/13/2015] [Indexed: 10/23/2022]
Abstract
The beta-2 adrenergic receptor (β2AR), a member of GPCR, can activate multiple signaling pathways and is an important treatment target for cardiac failure. However, the molecular mechanism about β2AR signaling regulation is not fully understood. In this study, we found that cystic fibrosis transmembrane conductance regulator-associated ligand (CAL) overexpression reduced β2AR-mediated extracellular signal-regulated kinase-1/2 (ERK1/2) activation. Further study identified CAL as a novel binding partner of β2AR. CAL is associated with β2AR mainly via the third intracellular loop (ICL3) of receptor and the coiled-coil domains of CAL, which is distinct from CAL/β1AR interaction mediated by the carboxyl terminal (CT) of β1AR and PDZ domain of CAL. CAL overexpression retarded β2AR expression in Golgi apparatus and reduced the receptor expression in plasma membrane.
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Affiliation(s)
- Longyan Yang
- Department of Biochemistry and Molecular Biology, Capital Medical University, No. 10 Xitoutiao, You An Men, Beijing, 100069, People's Republic of China
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43
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Singh V, Yang J, Cha B, Chen TE, Sarker R, Yin J, Avula LR, Tse M, Donowitz M. Sorting nexin 27 regulates basal and stimulated brush border trafficking of NHE3. Mol Biol Cell 2015; 26:2030-43. [PMID: 25851603 PMCID: PMC4472014 DOI: 10.1091/mbc.e14-12-1597] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Accepted: 04/01/2015] [Indexed: 12/21/2022] Open
Abstract
In polarized epithelial cells, SNX27 regulates PDZ domain–directed trafficking of NHE3 from endosomes to the plasma membrane and increases the stability of brush border NHE3. This establishes SNX27 as an important regulator of polarized sorting in epithelial cells. Sorting nexin 27 (SNX27) contains a PDZ domain that is phylogenetically related to the PDZ domains of the NHERF proteins. Studies on nonepithelial cells have shown that this protein is located in endosomes, where it regulates trafficking of cargo proteins in a PDZ domain–dependent manner. However, the role of SNX27 in trafficking of cargo proteins in epithelial cells has not been adequately explored. Here we show that SNX27 directly interacts with NHE3 (C-terminus) primarily through the SNX27 PDZ domain. A combination of knockdown and reconstitution experiments with wild type and a PDZ domain mutant (GYGF → GAGA) of SNX27 demonstrate that the PDZ domain of SNX27 is required to maintain basal NHE3 activity and surface expression of NHE3 in polarized epithelial cells. Biotinylation-based recycling and degradation studies in intestinal epithelial cells show that SNX27 is required for the exocytosis (not endocytosis) of NHE3 from early endosome to plasma membrane. SNX27 is also required to regulate the retention of NHE3 on the plasma membrane. The findings of the present study extend our understanding of PDZ-mediated recycling of cargo proteins from endosome to plasma membrane in epithelial cells.
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Affiliation(s)
- Varsha Singh
- Gastroenterology Division, Departments of Physiology and Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205
| | - Jianbo Yang
- Gastroenterology Division, Departments of Physiology and Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205
| | - Boyoung Cha
- Gastroenterology Division, Departments of Physiology and Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205
| | - Tiane-e Chen
- Gastroenterology Division, Departments of Physiology and Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205
| | - Rafiquel Sarker
- Gastroenterology Division, Departments of Physiology and Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205
| | - Jianyi Yin
- Gastroenterology Division, Departments of Physiology and Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205
| | - Leela Rani Avula
- Gastroenterology Division, Departments of Physiology and Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205
| | - Ming Tse
- Gastroenterology Division, Departments of Physiology and Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205
| | - Mark Donowitz
- Gastroenterology Division, Departments of Physiology and Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205
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44
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Pelaseyed T, Bergström JH, Gustafsson JK, Ermund A, Birchenough GMH, Schütte A, van der Post S, Svensson F, Rodríguez-Piñeiro AM, Nyström EEL, Wising C, Johansson MEV, Hansson GC. The mucus and mucins of the goblet cells and enterocytes provide the first defense line of the gastrointestinal tract and interact with the immune system. Immunol Rev 2015; 260:8-20. [PMID: 24942678 DOI: 10.1111/imr.12182] [Citation(s) in RCA: 775] [Impact Index Per Article: 86.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The gastrointestinal tract is covered by mucus that has different properties in the stomach, small intestine, and colon. The large highly glycosylated gel-forming mucins MUC2 and MUC5AC are the major components of the mucus in the intestine and stomach, respectively. In the small intestine, mucus limits the number of bacteria that can reach the epithelium and the Peyer's patches. In the large intestine, the inner mucus layer separates the commensal bacteria from the host epithelium. The outer colonic mucus layer is the natural habitat for the commensal bacteria. The intestinal goblet cells secrete not only the MUC2 mucin but also a number of typical mucus components: CLCA1, FCGBP, AGR2, ZG16, and TFF3. The goblet cells have recently been shown to have a novel gate-keeping role for the presentation of oral antigens to the immune system. Goblet cells deliver small intestinal luminal material to the lamina propria dendritic cells of the tolerogenic CD103(+) type. In addition to the gel-forming mucins, the transmembrane mucins MUC3, MUC12, and MUC17 form the enterocyte glycocalyx that can reach about a micrometer out from the brush border. The MUC17 mucin can shuttle from a surface to an intracellular vesicle localization, suggesting that enterocytes might control and report epithelial microbial challenge. There is communication not only from the epithelial cells to the immune system but also in the opposite direction. One example of this is IL10 that can affect and improve the properties of the inner colonic mucus layer. The mucus and epithelial cells of the gastrointestinal tract are the primary gate keepers and controllers of bacterial interactions with the host immune system, but our understanding of this relationship is still in its infancy.
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Affiliation(s)
- Thaher Pelaseyed
- Department of Medical Biochemistry, University of Gothenburg, Gothenburg, Sweden
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45
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Lu R, Stewart L, Wilson JM. Scaffolding protein GOPC regulates tight junction structure. Cell Tissue Res 2015; 360:321-32. [PMID: 25616555 DOI: 10.1007/s00441-014-2088-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Accepted: 12/04/2014] [Indexed: 11/30/2022]
Abstract
GOPC (FIG/PIST/CAL) is a PDZ-domain scaffolding protein that regulates the trafficking of a wide array of proteins, including small GTPases, receptors and cell surface molecules such as cadherin 23 and cystic fibrosis transmembrane regulator. In Madin-Darby canine kidney (MDCK) cells, we find that GOPC localizes to the trans-Golgi network (TGN) but not to the cis- or trans-Golgi cisternae. Colocalization occurs with the early endosome Rab GTPase Rab5 and a TGN/endosome marker Rab14 but not with Rab11, a marker of recycling endosomes. No localization of GOPC was detected to the lateral membranes or tight junctions. Knockdown of GOPC in MDCK cells results in decreased transepithelial resistance and increased paracellular flux. This might be attributable to the compromised trafficking of tight junction components from the TGN, as GOPC-knockdown cells have decreased lateral labeling of the tight junction protein claudin-1 and decreased protein levels of claudin-2. GOPC might mediate the trafficking of newly synthesized tight junction proteins from the TGN to the cell surface or the recycling of these proteins from specialized endosomal compartments.
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Affiliation(s)
- Ruifeng Lu
- Department of Cellular and Molecular Medicine, University of Arizona, PO Box 245044, Tucson, AZ 85724, USA
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46
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Alshafie W, Chappe FG, Li M, Anini Y, Chappe VM. VIP regulates CFTR membrane expression and function in Calu-3 cells by increasing its interaction with NHERF1 and P-ERM in a VPAC1- and PKCε-dependent manner. Am J Physiol Cell Physiol 2014; 307:C107-19. [DOI: 10.1152/ajpcell.00296.2013] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Vasoactive intestinal peptide (VIP) is a topical airway gland secretagogue regulating fluid secretions, primarily by stimulating cystic fibrosis transmembrane conductance regulator (CFTR)-dependent chloride secretion that contributes to the airways innate defense mechanism. We previously reported that prolonged VIP stimulation of pituitary adenylate cyclase-activating peptide receptors (VPAC1) in airway cells enhances CFTR function by increasing its membrane stability. In the present study, we identified the key effectors in the VIP signaling cascade in the human bronchial serous cell line Calu-3. Using immunocytochemistry and in situ proximity ligation assays, we found that VIP stimulation increased CFTR membrane localization by promoting its colocalization and interaction with the scaffolding protein Na+/H+ exchange factor 1 (NHERF1), a PDZ protein known as a positive regulator for CFTR membrane localization. VIP stimulation also increased phosphorylation, by protein kinase Cε of the actin-binding protein complex ezrin/radixin/moesin (ERM) and its interaction with NHERF1 and CFTR complex. On the other hand, it reduced intracellular CFTR colocalization and interaction with CFTR associated ligand, another PDZ protein known to compete with NHERF1 for CFTR interaction, inducing cytoplasmic retention and lysosomal degradation. Reducing NHERF1 or ERM expression levels by specific siRNAs prevented the VIP effect on CFTR membrane stability. Furthermore, iodide efflux assays confirmed that NHERF1 and P-ERM are necessary for VIP regulation of the stability and sustained activity of membrane CFTR. This study shows the cellular mechanism by which prolonged VIP stimulation of airway epithelial cells regulates CFTR-dependent secretions.
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Affiliation(s)
- Walaa Alshafie
- Departments of Physiology and Biophysics, Dalhousie University, Nova Scotia, Canada and
| | - Frederic G. Chappe
- Departments of Physiology and Biophysics, Dalhousie University, Nova Scotia, Canada and
| | - Mansong Li
- Departments of Physiology and Biophysics, Dalhousie University, Nova Scotia, Canada and
| | - Younes Anini
- Departments of Physiology and Biophysics, Dalhousie University, Nova Scotia, Canada and
- Obstetrics and Gynecology, Dalhousie University, Nova Scotia, Canada
| | - Valerie M. Chappe
- Departments of Physiology and Biophysics, Dalhousie University, Nova Scotia, Canada and
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Koeppen K, Coutermarsh BA, Madden DR, Stanton BA. Serum- and glucocorticoid-induced protein kinase 1 (SGK1) increases the cystic fibrosis transmembrane conductance regulator (CFTR) in airway epithelial cells by phosphorylating Shank2E protein. J Biol Chem 2014; 289:17142-50. [PMID: 24811177 DOI: 10.1074/jbc.m114.555599] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The glucocorticoid dexamethasone increases cystic fibrosis transmembrane conductance regulator (CFTR) abundance in human airway epithelial cells by a mechanism that requires serum- and glucocorticoid-induced protein kinase 1 (SGK1) activity. The goal of this study was to determine whether SGK1 increases CFTR abundance by phosphorylating Shank2E, a PDZ domain protein that contains two SGK1 phosphorylation consensus sites. We found that SGK1 phosphorylates Shank2E as well as a peptide containing the first SGK1 consensus motif of Shank2E. The dexamethasone-induced increase in CFTR abundance was diminished by overexpression of a dominant-negative Shank2E in which the SGK1 phosphorylation sites had been mutated. siRNA-mediated reduction of Shank2E also reduced the dexamethasone-induced increase in CFTR abundance. Taken together, these data demonstrate that the glucocorticoid-induced increase in CFTR abundance requires phosphorylation of Shank2E at an SGK1 consensus site.
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Affiliation(s)
- Katja Koeppen
- From the Department of Microbiology and Immunology and
| | | | - Dean R Madden
- Department of Biochemistry, The Geisel School of Medicine at Dartmouth, Hanover, New Hampshire 03755
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Abstract
Insulin regulates glucose uptake by controlling the subcellular location of GLUT4 glucose transporters. GLUT4 is sequestered within fat and muscle cells during low-insulin states, and is translocated to the cell surface upon insulin stimulation. The TUG protein is a functional tether that sequesters GLUT4 at the Golgi matrix. To stimulate glucose uptake, insulin triggers TUG endoproteolytic cleavage. Cleavage accounts for a large proportion of the acute effect of insulin to mobilize GLUT4 to the cell surface. During ongoing insulin exposure, endocytosed GLUT4 recycles to the plasma membrane directly from endosomes, and bypasses a TUG-regulated trafficking step. Insulin acts through the TC10α GTPase and its effector protein, PIST, to stimulate TUG cleavage. This action is coordinated with insulin signals through AS160/Tbc1D4 and Tbc1D1 to modulate Rab GTPases, and with other signals to direct overall GLUT4 targeting. Data support the idea that the N-terminal TUG cleavage product, TUGUL, functions as a novel ubiquitin-like protein modifier to facilitate GLUT4 movement to the cell surface. The C-terminal TUG cleavage product is extracted from the Golgi matrix, which vacates an "anchoring" site to permit subsequent cycles of GLUT4 retention and release. Together, GLUT4 vesicle translocation and TUG cleavage may coordinate glucose uptake with physiologic effects of other proteins present in the GLUT4-containing vesicles, and with potential additional effects of the TUG C-terminal product. Understanding this TUG pathway for GLUT4 retention and release will shed light on the regulation of glucose uptake and the pathogenesis of type 2 diabetes.
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Affiliation(s)
- Jonathan P Belman
- Section of Endocrinology and Metabolism, Department of Internal Medicine, and Department of Cell Biology, Yale University School of Medicine, 333 Cedar Street, Box 208020, New Haven, CT, 06520-8020, USA
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49
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Herrmann S, Ninkovic M, Kohl T, Pardo LA. PIST (GOPC) modulates the oncogenic voltage-gated potassium channel KV10.1. Front Physiol 2013; 4:201. [PMID: 23966943 PMCID: PMC3743135 DOI: 10.3389/fphys.2013.00201] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Accepted: 07/17/2013] [Indexed: 11/13/2022] Open
Abstract
Although crucial for their correct function, the mechanisms controlling surface expression of ion channels are poorly understood. In the case of the voltage-gated potassium channel KV10.1, this is determinant not only for its physiological function in brain, but also for its pathophysiology in tumors and possible use as a therapeutic target. The Golgi resident protein PIST binds several membrane proteins, thereby modulating their expression. Here we describe a PDZ domain-mediated interaction of KV10.1 and PIST, which enhances surface levels of KV10.1. The functional, but not the physical interaction of both proteins is dependent on the coiled-coil and PDZ domains of PIST; insertion of eight amino acids in the coiled-coil domain to render the neural form of PIST (nPIST) and the corresponding short isoform in an as-of-yet unknown form abolishes the effect. In addition, two new isoforms of PIST (sPIST and nsPIST) lacking nearly the complete PDZ domain were cloned and shown to be ubiquitously expressed. PIST and KV10.1 co-precipitate from native and expression systems. nPIST also showed interaction, but did not alter the functional expression of the channel. We could not document physical interaction between KV10.1 and sPIST, but it reduced KV10.1 functional expression in a dominant-negative manner. nsPIST showed weak physical interaction and no functional effect on KV10.1. We propose these isoforms to work as modulators of PIST function via regulating the binding on interaction partners.
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Affiliation(s)
- Solveig Herrmann
- AG Oncophysiology, Max-Planck Institute of Experimental Medicine Göttingen, Germany
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50
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Farinha CM, Matos P, Amaral MD. Control of cystic fibrosis transmembrane conductance regulator membrane trafficking: not just from the endoplasmic reticulum to the Golgi. FEBS J 2013; 280:4396-406. [PMID: 23773658 DOI: 10.1111/febs.12392] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 05/25/2013] [Accepted: 06/11/2013] [Indexed: 12/18/2022]
Abstract
Biogenesis of cystic fibrosis transmembrane conductance regulator (CFTR) starts with its cotranslational insertion into the membrane of the endoplasmic reticulum (ER) and core glycosylation. These initial events are followed by a complex succession of steps with the main goal of checking the overall quality of CFTR conformation in order to promote its exit from the ER through the secretory pathway. Failure to pass the various checkpoints of the ER quality control targets the most frequent disease-causing mutant protein (F508del-CFTR) for premature degradation. For wild-type CFTR that exits the ER, trafficking through the Golgi is the major site for glycan processing, although nonconventional trafficking pathways have also been described for CFTR. Once CFTR is at the cell surface, its stability is also controlled by multiple protein interactors, including Rab proteins, Rho small GTPases, and PDZ proteins. These regulate not only anterograde trafficking to the cell surface, but also endocytosis and recycling, thus achieving fine and tight modulation of CFTR plasma membrane levels. Exciting recent data have related autophagy and epithelial differentiation to the regulation of CFTR trafficking. Herein, we review the various checkpoints of the complex quality control along the secretory trafficking pathway and the associated pathways that are starting to be explored for the benefit of cystic fibrosis patients.
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Affiliation(s)
- Carlos M Farinha
- Faculty of Sciences, BioFIG - Centre for Biodiversity, Functional and Integrative Genomics, University of Lisboa, Portugal
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