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Cai Y, Li J, Fan K, Zhang D, Lu H, Chen G. Downregulation of Chloride voltage-gated channel 7 contributes to hyperalgesia following spared nerve injury. J Biol Chem 2024:107779. [PMID: 39276933 DOI: 10.1016/j.jbc.2024.107779] [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: 06/26/2024] [Revised: 08/22/2024] [Accepted: 08/30/2024] [Indexed: 09/17/2024] Open
Abstract
Alterations in anion balance potential, along with the involvement of cation-chloride cotransporters, play pivotal roles in the development of hyperalgesia after peripheral nerve injury (PNI). Chloride voltage-gated channel 7 (CLCN7) is the predominant member of the CLC protein family. Investigations on CLCN7 have focused primarily on its involvement in osteosclerosis and lysosomal storage disorders; nevertheless, its contribution to neuropathic pain (NP) has not been determined. In this investigation, we noted high expression of CLCN7 in neurons situated within the spinal dorsal horns (SDHs) and dorsal root ganglions (DRGs). Immunofluorescence analysis revealed that CLCN7 was predominantly distributed among IB4-positive and CGRP-positive neurons. Furthermore, the expression of CLCN7 was observed to be mainly reduced in neurons within the SDHs and in small and medium-sized neurons located in the DRGs of spared nerve injury (SNI) mice. Knockdown of CLCN7 via siRNA in the DRGs resulted in increased mechanical and thermal hyperalgesia in naïve mice. Furthermore, the excitability of cultured DRG neurons in vitro was augmented upon treatment with CLCN7 siRNA. These findings suggested that CLCN7 downregulation following SNI was crucial for the manifestation of mechanical and thermal hyperalgesia, highlighting potential targeting strategies for treating NP.
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Affiliation(s)
- Yunyun Cai
- Center for Basic Medical Research, Medical School of Nantong University, Co-innovation Center of Neuroregeneration, Nantong, Jiangsu Province, 226001, China
| | - Jiajie Li
- Department of Histology and Embryology, Medical School of Nantong University, Nantong, Jiangsu Province, 226001, China
| | - Kewei Fan
- Center for Basic Medical Research, Medical School of Nantong University, Co-innovation Center of Neuroregeneration, Nantong, Jiangsu Province, 226001, China
| | - Dongmei Zhang
- Department of Rehabilitation Medicine, Affiliated Hospital 2 of Nantong University, Nantong, 226001, Jiangsu Province, China; Jiangsu Provincial Medical Key Discipline (Laboratory) Cultivation Unit of Immunology, Nantong First People's Hospital, Nantong, 226001, Jiangsu Province, China
| | - Hongjian Lu
- Department of Rehabilitation Medicine, Affiliated Hospital 2 of Nantong University, Nantong, 226001, Jiangsu Province, China; Jiangsu Provincial Medical Key Discipline (Laboratory) Cultivation Unit of Immunology, Nantong First People's Hospital, Nantong, 226001, Jiangsu Province, China; Medical Research Center, Affiliated Hospital 2 of Nantong University, Nantong, 226001, Jiangsu Province, China.
| | - Gang Chen
- Center for Basic Medical Research, Medical School of Nantong University, Co-innovation Center of Neuroregeneration, Nantong, Jiangsu Province, 226001, China; Department of Anesthesiology, Affiliated Hospital of Nantong University, Nantong 226001, Jiangsu Province, China.
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2
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He H, Cao X, He F, Zhang W, Wang X, Peng P, Xie C, Yin F, Li D, Li J, Wang M, Klüssendorf M, Jentsch TJ, Stauber T, Peng J. Mutations in CLCN6 as a Novel Genetic Cause of Neuronal Ceroid Lipofuscinosis in a Murine Model. Ann Neurol 2024; 96:608-624. [PMID: 38877824 DOI: 10.1002/ana.27002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 04/30/2024] [Accepted: 05/08/2024] [Indexed: 06/16/2024]
Abstract
OBJECTIVE The aim of this study was to explore the pathogenesis of CLCN6-related disease and to assess whether its Cl-/H+-exchange activity is crucial for the biological role of ClC-6. METHODS We performed whole-exome sequencing on a girl with development delay, intractable epilepsy, behavioral abnormities, retinal dysfunction, progressive brain atrophy, suggestive of neuronal ceroid lipofuscinoses (NCLs). We generated and analyzed the first knock-in mouse model of a patient variant (p.E200A) and compared it with a Clcn6-/- mouse model. Additional functional tests were performed with heterologous expression of mutant ClC-6. RESULTS We identified a de novo heterozygous p.E200A variant in the proband. Expression of disease-causing ClC-6E200A or ClC-6Y553C mutants blocked autophagic flux and activated transcription factors EB (TFEB) and E3 (TFE3), leading to autophagic vesicle and cholesterol accumulation. Such alterations were absent with a transport-deficient ClC-6E267A mutant. Clcn6E200A/+ mice developed severe neurodegeneration with typical features of NCLs. Mutant ClC-6E200A, but not loss of ClC-6 in Clcn6-/- mice, increased lysosomal biogenesis by suppressing mTORC1-TFEB signaling, blocked autophagic flux through impairing lysosomal function, and increased apoptosis. Carbohydrate and lipid deposits accumulated in Clcn6E200A/+ brain, while only lipid storage was found in Clcn6-/- brain. Lysosome dysfunction, autophagy defects, and gliosis were early pathogenic events preceding neuron loss. INTERPRETATION CLCN6 is a novel genetic cause of NCLs, highlighting the importance of considering CLCN6 mutations in the diagnostic workup for molecularly undefined forms of NCLs. Uncoupling of Cl- transport from H+ countertransport in the E200A mutant has a dominant effect on the autophagic/lysosomal pathway. ANN NEUROL 2024;96:608-624.
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Affiliation(s)
- Hailan He
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Changsha, China
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
| | - Xiaoshuang Cao
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Changsha, China
| | - Fang He
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Changsha, China
| | - Wen Zhang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Changsha, China
| | - Xiaole Wang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Changsha, China
| | - Pan Peng
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Changsha, China
| | - Changning Xie
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Changsha, China
| | - Fei Yin
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Changsha, China
| | - Dengfeng Li
- Center for Medical Genetics, School of Life Sciences, Central South University, Changsha, China
- Hunan Key Laboratory of Animal Models for Human Diseases, Central South University, Changsha, China
| | - Jiada Li
- Center for Medical Genetics, School of Life Sciences, Central South University, Changsha, China
- Hunan Key Laboratory of Animal Models for Human Diseases, Central South University, Changsha, China
| | - Minghui Wang
- The First People's Hospital of Changde, Changde, China
| | - Malte Klüssendorf
- Institute for Molecular Medicine, MSH Medical School Hamburg, Hamburg, Germany
| | - Thomas J Jentsch
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP) and Max-Delbrück-Centrum für Molekulare Medizin (MDC), Berlin, Germany
- NeuroCure Cluster of Excellence, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Tobias Stauber
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
- Institute for Molecular Medicine, MSH Medical School Hamburg, Hamburg, Germany
| | - Jing Peng
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Changsha, China
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Morse J, Nadiveedhi MR, Schmidt M, Tang FK, Hladun C, Ganesh P, Qiu Z, Leung K. Tunable Cytosolic Chloride Indicators for Real-Time Chloride Imaging in Live Cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.08.606814. [PMID: 39149292 PMCID: PMC11326291 DOI: 10.1101/2024.08.08.606814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 08/17/2024]
Abstract
Chloride plays a crucial role in various cellular functions, and its level is regulated by a variety of chloride transporters and channels. However, to date, we still lack the capability to image instantaneous ion flux through chloride channels at single-cell level. Here, we developed a series of cell-permeable, pH-independent, chloride-sensitive fluorophores for real-time cytosolic chloride imaging, which we call CytoCl dyes. We demonstrated the ability of CytoCl dyes to monitor cytosolic chloride and used it to uncover the rapid changes and transient events of halide flux, which cannot be captured by steady-state imaging. Finally, we successfully imaged the proton-activated chloride channel-mediated ion flux at single-cell level, which is, to our knowledge, the first real-time imaging of ion flux through a chloride channel in unmodified cells. By enabling the imaging of single-cell level ion influx through chloride channels and transporters, CytoCl dyes can expand our understanding of ion flux dynamics, which is critical for characterization and modulator screening of these membrane proteins. A conjugable version of CytoCl dyes was also developed for its customization across different applications.
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Affiliation(s)
- Jared Morse
- Department of Chemistry & Biochemistry, Clarkson University, NY 13676, United States
| | | | - Matthias Schmidt
- Department of Chemistry & Biochemistry, Clarkson University, NY 13676, United States
| | - Fung-Kit Tang
- Department of Chemistry & Biochemistry, Clarkson University, NY 13676, United States
| | - Colby Hladun
- Department of Chemistry & Biochemistry, Clarkson University, NY 13676, United States
| | - Prasanna Ganesh
- Department of Chemistry & Biochemistry, Clarkson University, NY 13676, United States
| | - Zhaozhu Qiu
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, MD 21205, United States
| | - Kaho Leung
- Department of Chemistry & Biochemistry, Clarkson University, NY 13676, United States
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Polovitskaya MM, Rana T, Ullrich K, Murko S, Bierhals T, Vogt G, Stauber T, Kubisch C, Santer R, Jentsch TJ. Gain-of-function variants in CLCN7 cause hypopigmentation and lysosomal storage disease. J Biol Chem 2024; 300:107437. [PMID: 38838776 PMCID: PMC11261146 DOI: 10.1016/j.jbc.2024.107437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Revised: 05/08/2024] [Accepted: 05/23/2024] [Indexed: 06/07/2024] Open
Abstract
Together with its β-subunit OSTM1, ClC-7 performs 2Cl-/H+ exchange across lysosomal membranes. Pathogenic variants in either gene cause lysosome-related pathologies, including osteopetrosis and lysosomal storage. CLCN7 variants can cause recessive or dominant disease. Different variants entail different sets of symptoms. Loss of ClC-7 causes osteopetrosis and mostly neuronal lysosomal storage. A recently reported de novo CLCN7 mutation (p.Tyr715Cys) causes widespread severe lysosome pathology (hypopigmentation, organomegaly, and delayed myelination and development, "HOD syndrome"), but no osteopetrosis. We now describe two additional HOD individuals with the previously described p.Tyr715Cys and a novel p.Lys285Thr mutation, respectively. Both mutations decreased ClC-7 inhibition by PI(3,5)P2 and affected residues lining its binding pocket, and shifted voltage-dependent gating to less positive potentials, an effect partially conferred to WT subunits in WT/mutant heteromers. This shift predicts augmented pH gradient-driven Cl- uptake into vesicles. Overexpressing either mutant induced large lysosome-related vacuoles. This effect depended on Cl-/H+-exchange, as shown using mutants carrying uncoupling mutations. Fibroblasts from the p.Y715C patient also displayed giant vacuoles. This was not observed with p.K285T fibroblasts probably due to residual PI(3,5)P2 sensitivity. The gain of function caused by the shifted voltage-dependence of either mutant likely is the main pathogenic factor. Loss of PI(3,5)P2 inhibition will further increase current amplitudes, but may not be a general feature of HOD. Overactivity of ClC-7 induces pathologically enlarged vacuoles in many tissues, which is distinct from lysosomal storage observed with the loss of ClC-7 function. Osteopetrosis results from a loss of ClC-7, but osteoclasts remain resilient to increased ClC-7 activity.
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Affiliation(s)
- Maya M Polovitskaya
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany
| | - Tanushka Rana
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany; Graduate program of Humboldt-Universität zu Berlin and Graduate School of the Max Delbrück Centre for Molecular Medicine (MDC), Berlin, Germany
| | - Kurt Ullrich
- Department of Pediatrics, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Simona Murko
- Department of Pediatrics, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Tatjana Bierhals
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Guido Vogt
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany
| | - Tobias Stauber
- Institute for Molecular Medicine, Medical School Hamburg (MSH), Hamburg, Germany
| | - Christian Kubisch
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - René Santer
- Department of Pediatrics, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany.
| | - Thomas J Jentsch
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany; NeuroCure Cluster of Excellence, Charité Universitätsmedizin, Berlin, Germany.
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Lee C, Chang Y, Lin H, Lee H, Yeh T, Fang L, Lee N, Tsai J, Lin S. Multisystem disorder associated with a pathogenic variant in CLCN7 in the absence of osteopetrosis. Mol Genet Genomic Med 2024; 12:e2494. [PMID: 39056574 PMCID: PMC11273547 DOI: 10.1002/mgg3.2494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 05/08/2024] [Accepted: 07/02/2024] [Indexed: 07/28/2024] Open
Abstract
BACKGROUND We clinically and genetically evaluated a Taiwanese boy presenting with developmental delay, organomegaly, hypogammaglobulinemia and hypopigmentation without osteopetrosis. Whole-exome sequencing revealed a de novo gain-of-function variant, p.Tyr715Cys, in the C-terminal domain of ClC-7 encoded by CLCN7. METHODS Nicoli et al. (2019) assessed the functional impact of p.Tyr715Cys by heterologous expression in Xenopus oocytes and evaluating resulting currents. RESULTS The variant led to increased outward currents, indicating it underlies the patient's phenotype of lysosomal hyperacidity, storage defects and vacuolization. This demonstrates the crucial physiological role of ClC-7 antiporter activity in maintaining appropriate lysosomal pH. CONCLUSION Elucidating mechanisms by which CLCN7 variants lead to lysosomal dysfunction will advance understanding of genotype-phenotype correlations. Identifying modifier genes and compensatory pathways may reveal therapeutic targets. Ongoing functional characterization of variants along with longitudinal clinical evaluations will continue advancing knowledge of ClC-7's critical roles and disease mechanisms resulting from its dysfunction. Expanded cohort studies are warranted to delineate the full spectrum of associated phenotypes.
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Affiliation(s)
- Chung‐Lin Lee
- Department of PediatricsMacKay Memorial HospitalTaipeiTaiwan
- Department and Institute of Clinical MedicineNational Yang‐Ming Chiao‐Tung UniversityTaipeiTaiwan
- Department of Rare Disease CenterMacKay Memorial HospitalTaipeiTaiwan
- Department of MedicineMackay Medical CollegeNew Taipei CityTaiwan
- Mackay Junior College of Medicine, Nursing, and ManagementTaipeiTaiwan
| | - Yeun‐Wen Chang
- Department of PediatricsMacKay Memorial HospitalTaipeiTaiwan
- Department of PediatricsTaipei Tzu Chi Hospital, Buddhist Tzu Chi Medical FoundationNew Taipei CityTaiwan
| | - Hsiang‐Yu Lin
- Department of PediatricsMacKay Memorial HospitalTaipeiTaiwan
- Department of Rare Disease CenterMacKay Memorial HospitalTaipeiTaiwan
- Department of MedicineMackay Medical CollegeNew Taipei CityTaiwan
- Mackay Junior College of Medicine, Nursing, and ManagementTaipeiTaiwan
- Division of Genetics and Metabolism, Department of Medical ResearchMacKay Memorial HospitalTaipeiTaiwan
- Department of Medical ResearchChina Medical University Hospital, China Medical UniversityTaichungTaiwan
| | - Hung‐Chang Lee
- Department of PediatricsMacKay Memorial HospitalTaipeiTaiwan
| | - Ting‐Chi Yeh
- Department of PediatricsMacKay Memorial HospitalTaipeiTaiwan
| | - Li‐Ching Fang
- Department of PediatricsMacKay Memorial HospitalTaipeiTaiwan
| | - Ni‐Chung Lee
- Department of PediatricsNational Taiwan University HospitalTaipeiTaiwan
| | - Jeng‐Daw Tsai
- Department of PediatricsMacKay Memorial HospitalTaipeiTaiwan
- Department of MedicineMackay Medical CollegeNew Taipei CityTaiwan
| | - Shuan‐Pei Lin
- Department of PediatricsMacKay Memorial HospitalTaipeiTaiwan
- Department of Rare Disease CenterMacKay Memorial HospitalTaipeiTaiwan
- Department of MedicineMackay Medical CollegeNew Taipei CityTaiwan
- Division of Genetics and Metabolism, Department of Medical ResearchMacKay Memorial HospitalTaipeiTaiwan
- Department of Infant and Child CareNational Taipei University of Nursing and Health SciencesTaipeiTaiwan
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Cen J, Hu N, Shen J, Gao Y, Lu H. Pathological Functions of Lysosomal Ion Channels in the Central Nervous System. Int J Mol Sci 2024; 25:6565. [PMID: 38928271 PMCID: PMC11203704 DOI: 10.3390/ijms25126565] [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: 04/03/2024] [Revised: 06/06/2024] [Accepted: 06/10/2024] [Indexed: 06/28/2024] Open
Abstract
Lysosomes are highly dynamic organelles that maintain cellular homeostasis and regulate fundamental cellular processes by integrating multiple metabolic pathways. Lysosomal ion channels such as TRPML1-3, TPC1/2, ClC6/7, CLN7, and TMEM175 mediate the flux of Ca2+, Cl-, Na+, H+, and K+ across lysosomal membranes in response to osmotic stimulus, nutrient-dependent signals, and cellular stresses. These ion channels serve as the crucial transducers of cell signals and are essential for the regulation of lysosomal biogenesis, motility, membrane contact site formation, and lysosomal homeostasis. In terms of pathophysiology, genetic variations in these channel genes have been associated with the development of lysosomal storage diseases, neurodegenerative diseases, inflammation, and cancer. This review aims to discuss the current understanding of the role of these ion channels in the central nervous system and to assess their potential as drug targets.
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Affiliation(s)
| | | | | | - Yongjing Gao
- Institute of Pain Medicine and Special Environmental Medicine, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong 226019, China; (J.C.); (N.H.); (J.S.)
| | - Huanjun Lu
- Institute of Pain Medicine and Special Environmental Medicine, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong 226019, China; (J.C.); (N.H.); (J.S.)
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Kimera L, Nadimpalli S, Kurup S, Sessions Cole F, Huang R, Sisco K, Ranaivo HR, Shinawi M, Dickson P, Mian A, Reynolds M. Case report: ocular manifestations of a gain-of-function mutation in CLCN6, a newly diagnosed disease. Ophthalmic Genet 2024; 45:271-274. [PMID: 38095064 PMCID: PMC11176260 DOI: 10.1080/13816810.2023.2291683] [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: 04/19/2023] [Revised: 10/31/2023] [Accepted: 11/30/2023] [Indexed: 02/23/2024]
Abstract
BACKGROUND In 2020, a new disease was reported by Polovitskaya et al., caused by a monoallelic, gain-of-function mutation in CLCN6, encoding the ClC-6 Cl-/H±exchanger. METHODS Here, we report the ophthalmic findings of one of the first three patients with this disease (the proband) and review the findings in the other two patients in the literature. RESULTS The CLCN6 gene is part of the voltage-dependent chloride channel protein family. It functions as either a chloride channel aiding in cell-volume regulation and acidification of intracellular organelles or as an antiporter, which are membrane proteins involved in the transport of molecules across a phospholipid membrane. This particular gene is found in late endosomes. Ion transport across endosome membranes is essential for endosomal function. The proband carried a de novo c.1658A>G (p.Tyr553Cys) mutation in CLCN6. The patient reported herein has a notable optic nerve appearance. The nerve initially appeared elevated. Over time, the optic nerve elevation appearance decreased, associated with progressive vision loss with a visual acuity of 20/470 at last follow-up. CONCLUSION While Clcn6-/- mice have been found to have a mild neuronal lysosomal storage phenotype, the three reported children with a de novo c.1658A>G (p.Tyr553Cys) variant displayed significant developmental delay and neurodegeneration.
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Affiliation(s)
- Lawrencia Kimera
- Department of Ophthalmology and Visual Sciences, Washington University in St. Louis School of Medicine, St. Louis, MO, USA
| | - Sameera Nadimpalli
- Division of Ophthalmology, Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, IL, USA
| | - Sudhi Kurup
- Division of Ophthalmology, Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, IL, USA
- Department of Ophthalmology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - F. Sessions Cole
- Department of Pediatrics, Division of Neonatal Medicine, Washington University in St. Louis School of Medicine, St. Louis, MO, USA
- Department of Cell and Molecular Biology, Washington University in St. Louis School of Medicine, St. Louis, MO, USA
| | - Russell Huang
- Department of Ophthalmology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Kathleen Sisco
- Department of Pediatrics, Division of Genetics and Genomic Medicine, Washington University in St. Louis School of Medicine, St. Louis, MO, USA
| | | | - Marwan Shinawi
- Department of Pediatrics, Division of Genetics and Genomic Medicine, Washington University in St. Louis School of Medicine, St. Louis, MO, USA
| | - Patricia Dickson
- Department of Pediatrics, Division of Genetics and Genomic Medicine, Washington University in St. Louis School of Medicine, St. Louis, MO, USA
| | - Ali Mian
- Department of Radiology, Section of Neuroradiology, Washington University in St. Louis School of Medicine, St. Louis, MO, USA
| | - Margaret Reynolds
- Department of Ophthalmology and Visual Sciences, Washington University in St. Louis School of Medicine, St. Louis, MO, USA
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Kwon HC, Fairclough RH, Chen TY. Biophysical and Pharmacological Insights to CLC Chloride Channels. Handb Exp Pharmacol 2024; 283:1-34. [PMID: 35768555 DOI: 10.1007/164_2022_594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The CLC family encompasses two functional categories of transmembrane proteins: chloride conducting channels and proton-chloride antiporters. All members in this chloride channel/transporter family consist of two identical protein subunits, and each subunit forms an independent ion-transport pathway, a structural architecture known as "double barrel." These CLC proteins serve biological functions ranging from membrane excitability and cell volume regulation to acidification of endosomes. Despite their ubiquitous expression, physiological significance, and resolved molecular structures of some of the family members, the mechanisms governing these molecules' biophysical functions are still not completely settled. However, a series of functional and structural studies have brought insights into interesting questions related to these proteins. This chapter explores the functional peculiarities underlying CLC channels aided by information observed from the chloride-proton antiporters in the CLC family. The overall structural features of these CLC proteins will be presented, and the biophysical functions will be addressed. Finally, the mechanism of pharmacological agents that interact with CLC channels will also be discussed.
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Affiliation(s)
- Hwoi Chan Kwon
- Center for Neuroscience and Biophysics Graduate Group, University of California, Davis, CA, USA
| | - Robert H Fairclough
- Department of Neurology and the Biophysics Graduate Group, University of California, Davis, CA, USA
| | - Tsung-Yu Chen
- Center for Neuroscience, Department of Neurology, and Biophysics Graduate Group, University of California, Davis, CA, USA.
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Coppola MA, Gavazzo P, Zanardi I, Tettey-Matey A, Liantonio A, Fong P, Pusch M. Distinct ClC-6 and ClC-7 Cl - sensitivities provide insight into ClC-7's role in lysosomal Cl - homeostasis. J Physiol 2023; 601:5635-5653. [PMID: 37937509 PMCID: PMC10842065 DOI: 10.1113/jp285431] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 10/16/2023] [Indexed: 11/09/2023] Open
Abstract
ClC-6 and ClC-7 are closely related, intracellular Cl- /H+ antiporters belonging to the CLC family of channels and transporters. They localize to acidic late endosomes and lysosomes and probably function in ionic homeostasis of these contiguous compartments. ClC-7 transport function requires association with the accessory protein Ostm1, whereas ClC-6 transport does not. To elucidate their roles in endo-lysosomes, we measured Cl- - and pH-dependences of over-expressed wild-type ClC-6 and ClC-7, as well as disease-associated mutants, using high-resolution recording protocols. Lowering extracellular Cl- (corresponding to luminal Cl- in endo-lysosomes) reduced ClC-6 currents, whereas it increased transport activity of ClC-7/Ostm1. Low extracellular Cl- activated ClC-7/Ostm 1 under acidic extracellular conditions, as well as under conditions of low intracellular chloride. Activation is conserved in ClC-7Y713C , a variant displaying disrupted PI(3,5)P2 inhibition. Detailed biophysical analysis of disease-associated ClC-6 and ClC-7 gain-of-function (GoF) variants, ClC-6Y553C and ClC-7Y713C , and the ClC-7Y577C and ClC-6Y781C correlates, identified additional functional nuances distinguishing ClC-6 and ClC-7. ClC-7Y577C recapitulated GoF produced by ClC-6Y553C . ClC-6Y781C displayed transport activation qualitatively similar to ClC-7Y713C , although current density did not differ from that of wild-type ClC-6. Finally, rClC-7R760Q , homologous to hClC-7R762Q , an osteopetrosis variant with fast gating kinetics, appeared indifferent to extracellular Cl- , identifying altered Cl- sensitivity as a plausible mechanism underlying disease. Collectively, the present studies underscore the distinct roles of ClC-6 and ClC-7 within the context of their respective localization to late endosomes and lysosomes. In particular, we suggest the atypical inhibition of ClC-7 by luminal Cl- serves to limit excessive intraluminal Cl- accumulation. KEY POINTS: ClC-6 and ClC-7 are late endosomal and lysosomal 2 Cl- /1 H+ exchangers, respectively. When targeted to the plasma membrane, both activate slowly at positive voltages. ClC-6 activity is decreased in low extracellular (i.e. luminal) chloride, whereas ClC-7 is activated by low luminal chloride, even at acidic pH. The functional gain-of-function phenotypes of the ClC-6 and ClC-7 disease mutations ClC-6Y553C and ClC-7Y715C are maintained when introduced in their respective homologues, ClC-7Y577C and ClC-6Y781C , with all mutations retaining chloride dependence of the respective wild type (WT). An osteopetrosis mutation of ClC-7 displaying fast gating kinetics (R762Q) was less sensitive to extracellular chloride compared to WT. The opposing substrate dependences of ClC-6 and ClC-7 Cl- / H+ exchangers point to non-overlapping physiological functions, leading us to propose that inhibition of ClC-7 by luminal chloride and protons serves to prevent osmotic stress imposed by hyper-accumulation of chloride.
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Affiliation(s)
- Maria Antonietta Coppola
- Institute of Biophysics, CNR, Genoa, Italy
- Department of Pharmacy–Drug Sciences, University of Bari “Aldo Moro”, Bari, Italy
| | | | | | | | - Antonella Liantonio
- Department of Pharmacy–Drug Sciences, University of Bari “Aldo Moro”, Bari, Italy
| | - Peying Fong
- Department of Anatomy and Physiology, Kansas State University College of Veterinary Medicine, Manhattan, KS, USA
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10
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Picollo A. Vesicular CLC chloride/proton exchangers in health and diseases. Front Pharmacol 2023; 14:1295068. [PMID: 38027030 PMCID: PMC10662042 DOI: 10.3389/fphar.2023.1295068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Accepted: 10/16/2023] [Indexed: 12/01/2023] Open
Abstract
Chloride is one of the most abundant anions in the human body; it is implicated in several physiological processes such as the transmission of action potentials, transepithelial salt transport, maintenance of cellular homeostasis, regulation of osmotic pressure and intracellular pH, and synaptic transmission. The balance between the extracellular and intracellular chloride concentrations is controlled by the interplay of ion channels and transporters embedded in the cellular membranes. Vesicular members of the CLC chloride protein family (vCLCs) are chloride/proton exchangers expressed in the membrane of the intracellular organelles, where they control vesicular acidification and luminal chloride concentration. It is well known that mutations in CLCs cause bone, kidney, and lysosomal genetic diseases. However, the role of CLC exchangers in neurological disorders is only now emerging with the identification of pathogenic CLCN gene variants in patients with severe neuronal and intellectual dysfunctions. This review will provide an overview of the recent advances in understanding the role of the vesicular CLC chloride/proton exchangers in human pathophysiology.
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Affiliation(s)
- Alessandra Picollo
- Institute of Biophysics, National Research Council, Genova, Italy
- RAISE Ecosystem, Genova, Italy
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11
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Zhang B, Zhang S, Polovitskaya MM, Yi J, Ye B, Li R, Huang X, Yin J, Neuens S, Balfroid T, Soblet J, Vens D, Aeby A, Li X, Cai J, Song Y, Li Y, Tartaglia M, Li Y, Jentsch TJ, Yang M, Liu Z. Molecular basis of ClC-6 function and its impairment in human disease. SCIENCE ADVANCES 2023; 9:eadg4479. [PMID: 37831762 PMCID: PMC10575590 DOI: 10.1126/sciadv.adg4479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2022] [Accepted: 09/08/2023] [Indexed: 10/15/2023]
Abstract
ClC-6 is a late endosomal voltage-gated chloride-proton exchanger that is predominantly expressed in the nervous system. Mutated forms of ClC-6 are associated with severe neurological disease. However, the mechanistic role of ClC-6 in normal and pathological states remains largely unknown. Here, we present cryo-EM structures of ClC-6 that guided subsequent functional studies. Previously unrecognized ATP binding to cytosolic ClC-6 domains enhanced ion transport activity. Guided by a disease-causing mutation (p.Y553C), we identified an interaction network formed by Y553/F317/T520 as potential hotspot for disease-causing mutations. This was validated by the identification of a patient with a de novo pathogenic variant p.T520A. Extending these findings, we found contacts between intramembrane helices and connecting loops that modulate the voltage dependence of ClC-6 gating and constitute additional candidate regions for disease-associated gain-of-function mutations. Besides providing insights into the structure, function, and regulation of ClC-6, our work correctly predicts hotspots for CLCN6 mutations in neurodegenerative disorders.
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Affiliation(s)
- Bing Zhang
- Shanghai Key Laboratory of Maternal Fetal Medicine, Shanghai Institute of Maternal-Fetal Medicine and Gynecologic Oncology, Department of Anesthesiology, Clinical and Translational Research Center, Shanghai First Maternity and Infant Hospital, School of Medicine, Tongji University, 201204 Shanghai, China
| | - Sensen Zhang
- Ministry of Education Key Laboratory of Protein Science, Beijing Advanced Innovation Center for Structural Biology, Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, 100084 Beijing, China
| | - Maya M. Polovitskaya
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), 13125 Berlin, Germany
- Max-Delbrück-Centrum für Molekulare Medizin (MDC), 13125 Berlin, Germany
| | - Jingbo Yi
- Ministry of Education Key Laboratory of Protein Science, Beijing Advanced Innovation Center for Structural Biology, Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, 100084 Beijing, China
| | - Binglu Ye
- Shanghai Key Laboratory of Maternal Fetal Medicine, Shanghai Institute of Maternal-Fetal Medicine and Gynecologic Oncology, Department of Anesthesiology, Clinical and Translational Research Center, Shanghai First Maternity and Infant Hospital, School of Medicine, Tongji University, 201204 Shanghai, China
| | - Ruochong Li
- Ministry of Education Key Laboratory of Protein Science, Beijing Advanced Innovation Center for Structural Biology, Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, 100084 Beijing, China
| | - Xueying Huang
- Shanghai Key Laboratory of Maternal Fetal Medicine, Shanghai Institute of Maternal-Fetal Medicine and Gynecologic Oncology, Department of Anesthesiology, Clinical and Translational Research Center, Shanghai First Maternity and Infant Hospital, School of Medicine, Tongji University, 201204 Shanghai, China
| | - Jian Yin
- Ministry of Education Key Laboratory of Protein Science, Beijing Advanced Innovation Center for Structural Biology, Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, 100084 Beijing, China
| | - Sebastian Neuens
- Department of Genetics, Hôpital Universitaire des Enfants Reine Fabiola, Université Libre de Bruxelles (ULB), Brussels, Belgium
| | - Tom Balfroid
- Department of Pediatric Neurology, Hôpital Universitaire des Enfants Reine Fabiola, Université Libre de Bruxelles (ULB), Brussels, Belgium
| | - Julie Soblet
- Department of Genetics, Hôpital Universitaire des Enfants Reine Fabiola, Université Libre de Bruxelles (ULB), Brussels, Belgium
- Department of Genetics, Hôpital Erasme, Université Libre de Bruxelles (ULB), Brussels, Belgium
- Interuniversity Institute of Bioinformatics in Brussels, Université Libre de Bruxelles (ULB), Brussels, Belgium
| | - Daphné Vens
- Pediatric Intensive Care Unit, Hôpital Universitaire des Enfants Reine Fabiola, Université Libre de Bruxelles (ULB), Brussels, Belgium
| | - Alec Aeby
- Department of Pediatric Neurology, Hôpital Universitaire des Enfants Reine Fabiola, Université Libre de Bruxelles (ULB), Brussels, Belgium
| | - Xiaoling Li
- Wuya College of Innovation, Shenyang Pharmaceutical University, 110016 Shenyang, China
| | - Jinjin Cai
- Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 201203 Shanghai, China
| | - Yingcai Song
- Shanghai Key Laboratory of Maternal Fetal Medicine, Shanghai Institute of Maternal-Fetal Medicine and Gynecologic Oncology, Department of Anesthesiology, Clinical and Translational Research Center, Shanghai First Maternity and Infant Hospital, School of Medicine, Tongji University, 201204 Shanghai, China
| | - Yuanxi Li
- Institute for Cognitive Neurodynamics, School of Mathematics, East China University of Science and Technology, 200237 Shanghai, China
| | - Marco Tartaglia
- Molecular Genetics and Functional Genomics, Ospedale Pediatrico Bambino Gesù, IRCCS, 00146 Rome, Italy
| | - Yang Li
- Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 201203 Shanghai, China
- National Clinical Research Center for Aging and Medicine, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Thomas J. Jentsch
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), 13125 Berlin, Germany
- Max-Delbrück-Centrum für Molekulare Medizin (MDC), 13125 Berlin, Germany
- NeuroCure Cluster of Excellence, Charité Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Maojun Yang
- Ministry of Education Key Laboratory of Protein Science, Beijing Advanced Innovation Center for Structural Biology, Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, 100084 Beijing, China
- Cryo-EM Facility Center, Southern University of Science & Technology, 518055 Shenzhen, Guangdong, China
| | - Zhiqiang Liu
- Shanghai Key Laboratory of Maternal Fetal Medicine, Shanghai Institute of Maternal-Fetal Medicine and Gynecologic Oncology, Department of Anesthesiology, Clinical and Translational Research Center, Shanghai First Maternity and Infant Hospital, School of Medicine, Tongji University, 201204 Shanghai, China
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12
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Wang C, Li J, Liu W, Li S, Zhang Y, Jin Y, Cui J. Comprehensive analysis and experimental validation reveal elevated CLCN4 is a promising biomarker in endometrial cancer. Aging (Albany NY) 2023; 15:8744-8769. [PMID: 37671947 PMCID: PMC10522378 DOI: 10.18632/aging.204994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 07/25/2023] [Indexed: 09/07/2023]
Abstract
Several studies have reported the role of CLCN4 in tumor progression. However, its mechanism remains to be thoroughly studied. The objective of this study was to explore the potential pathogenic role of CLCN4 in endometrial carcinoma (UCEC) with a better understanding of the pathological mechanisms involved. The potential roles of CLCN4 in different tumors were explored based on The Cancer Genome Atlas (TCGA), the expression difference, mutation, survival, pathological stage, Immunity subtypes, Immune infiltration, tumor microenvironment (TME), tumor mutation burden (TMB), microsatellite instability (MSI), mismatch repair (MMR) related to CLCN4 were analyzed. Then, the expression, prognosis, mutation, and functional enrichment of CLCN4 in UCEC were analyzed. Immunohistochemical experiment was used to verify the expression of CLCN4 in endometrial cancer tissues and normal tissues. In vitro, we knocked down of CLCN4 in HEC-1-A cells and performed CCK8, WB, RT-PCR, wound-healing, transwell assays to further validation of the molecular function. Results revealed that high expression of CLCN4 was observed in 20 cancer types of TCGA. CLCN4 expression correlates with poor survival in MESO, BLCA, THCA, especially UCEC tumors. CLCN4 expression was significantly associated with CD4+ T-cell infiltration, especially CD4+ Th1-cell. Immunohistochemical experiment reveals that CLCN4 is high expressed in endometrial tumors, in vitro experiment reveals that knockdown of CLCN4 inhibits the cells proliferation, migration and invasion. Our study is the first to offer a comprehensive understanding of the oncogenic roles of CLCN4 on different tumors. CLCN4 may become a potential biomarker in UCEC.
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Affiliation(s)
- Chenyang Wang
- Department of Gynecology, The Second Affiliated Hospital of Zhengzhou University, Zhengzhou 450000, China
- Academy of Medical Sciences, Zhengzhou University, Zhengzhou 450000, China
| | - Jing Li
- Department of Gynecology, Qingdao Hospital, University of Health and Rehabilitation Sciences (Qingdao Municipal Hospital), Qingdao, Shandong 266000, China
| | - Weina Liu
- Department of Gynecology, The Second Affiliated Hospital of Zhengzhou University, Zhengzhou 450000, China
- Academy of Medical Sciences, Zhengzhou University, Zhengzhou 450000, China
| | - Shiya Li
- Department of Gynecology, The Second Affiliated Hospital of Zhengzhou University, Zhengzhou 450000, China
- Academy of Medical Sciences, Zhengzhou University, Zhengzhou 450000, China
| | - Yi Zhang
- Department of Gynecology, The University of Auckland, Grafton, Auckland 1023, New Zealand
| | - Yanbin Jin
- Department of Gynecology, Hainan Affiliated Hospital of Hainan Medical University (Hainan General Hospital), Haikou 570311, China
| | - Jinquan Cui
- Department of Gynecology, The Second Affiliated Hospital of Zhengzhou University, Zhengzhou 450000, China
- Academy of Medical Sciences, Zhengzhou University, Zhengzhou 450000, China
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13
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Cao X, Lenk GM, Mikusevic V, Mindell JA, Meisler MH. The chloride antiporter CLCN7 is a modifier of lysosome dysfunction in FIG 4 and VAC14 mutants. PLoS Genet 2023; 19:e1010800. [PMID: 37363915 DOI: 10.1371/journal.pgen.1010800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Accepted: 05/26/2023] [Indexed: 06/28/2023] Open
Abstract
The phosphatase FIG 4 and the scaffold protein VAC14 function in the biosynthesis of PI(3,5)P2, a signaling lipid that inhibits the lysosomal chloride transporter ClC-7. Loss-of-function mutations of FIG 4 and VAC14 reduce PI(3,5)P2 and result in lysosomal disorders characterized by accumulation of enlarged lysosomes and neurodegeneration. Similarly, a gain of function mutation of CLCN7 encoding ClC-7 also results in enlarged lysosomes. We therefore tested the ability of reduced CLCN7 expression to compensate for loss of FIG 4 or VAC14. Knock-out of CLCN7 corrected lysosomal swelling and partially corrected lysosomal hyperacidification in FIG 4 null cell cultures. Knockout of the related transporter CLCN6 (ClC-6) in FIG 4 null cells did not affect the lysosome phenotype. In the Fig 4 null mouse, reduction of ClC-7 by expression of the dominant negative CLCN7 variant p.Gly215Arg improved growth and neurological function and increased lifespan by 20%. These observations demonstrate a role for the CLCN7 chloride transporter in pathogenesis of FIG 4 and VAC14 disorders. Reduction of CLCN7 provides a new target for treatment of FIG 4 and VAC14 deficiencies that lack specific therapies, such as Charcot-Marie-Tooth Type 4J and Yunis-Varón syndrome.
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Affiliation(s)
- Xu Cao
- Department of Human Genetics, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Guy M Lenk
- Department of Human Genetics, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Vedrana Mikusevic
- Membrane Transport Biophysics Section, National Institutes of Neurological Disorders and Stroke, Bethesda, Maryland, United States of America
| | - Joseph A Mindell
- Membrane Transport Biophysics Section, National Institutes of Neurological Disorders and Stroke, Bethesda, Maryland, United States of America
| | - Miriam H Meisler
- Department of Human Genetics, University of Michigan, Ann Arbor, Michigan, United States of America
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14
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Coppola MA, Tettey-Matey A, Imbrici P, Gavazzo P, Liantonio A, Pusch M. Biophysical Aspects of Neurodegenerative and Neurodevelopmental Disorders Involving Endo-/Lysosomal CLC Cl -/H + Antiporters. Life (Basel) 2023; 13:1317. [PMID: 37374100 DOI: 10.3390/life13061317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 05/30/2023] [Accepted: 05/31/2023] [Indexed: 06/29/2023] Open
Abstract
Endosomes and lysosomes are intracellular vesicular organelles with important roles in cell functions such as protein homeostasis, clearance of extracellular material, and autophagy. Endolysosomes are characterized by an acidic luminal pH that is critical for proper function. Five members of the gene family of voltage-gated ChLoride Channels (CLC proteins) are localized to endolysosomal membranes, carrying out anion/proton exchange activity and thereby regulating pH and chloride concentration. Mutations in these vesicular CLCs cause global developmental delay, intellectual disability, various psychiatric conditions, lysosomal storage diseases, and neurodegeneration, resulting in severe pathologies or even death. Currently, there is no cure for any of these diseases. Here, we review the various diseases in which these proteins are involved and discuss the peculiar biophysical properties of the WT transporter and how these properties are altered in specific neurodegenerative and neurodevelopmental disorders.
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Affiliation(s)
- Maria Antonietta Coppola
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, 16149 Genova, Italy
- Department of Pharmacy-Drug Sciences, University of Bari "Aldo Moro", 70125 Bari, Italy
| | | | - Paola Imbrici
- Department of Pharmacy-Drug Sciences, University of Bari "Aldo Moro", 70125 Bari, Italy
| | - Paola Gavazzo
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, 16149 Genova, Italy
| | - Antonella Liantonio
- Department of Pharmacy-Drug Sciences, University of Bari "Aldo Moro", 70125 Bari, Italy
| | - Michael Pusch
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, 16149 Genova, Italy
- RAISE Ecosystem, 16149 Genova, Italy
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15
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Mendes LC, Viana GMM, Nencioni ALA, Pimenta DC, Beraldo-Neto E. Scorpion Peptides and Ion Channels: An Insightful Review of Mechanisms and Drug Development. Toxins (Basel) 2023; 15:238. [PMID: 37104176 PMCID: PMC10145618 DOI: 10.3390/toxins15040238] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 03/21/2023] [Accepted: 03/22/2023] [Indexed: 04/28/2023] Open
Abstract
The Buthidae family of scorpions consists of arthropods with significant medical relevance, as their venom contains a diverse range of biomolecules, including neurotoxins that selectively target ion channels in cell membranes. These ion channels play a crucial role in regulating physiological processes, and any disturbance in their activity can result in channelopathies, which can lead to various diseases such as autoimmune, cardiovascular, immunological, neurological, and neoplastic conditions. Given the importance of ion channels, scorpion peptides represent a valuable resource for developing drugs with targeted specificity for these channels. This review provides a comprehensive overview of the structure and classification of ion channels, the action of scorpion toxins on these channels, and potential avenues for future research. Overall, this review highlights the significance of scorpion venom as a promising source for discovering novel drugs with therapeutic potential for treating channelopathies.
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Affiliation(s)
- Lais Campelo Mendes
- Programa de Pós-Graduação em Ciências—Toxinologia do Instituto Butantan, São Paulo 05503-900, Brazil
- Laboratório de Bioquímica do Instituto Butantan, São Paulo 05503-900, Brazil
| | | | | | | | - Emidio Beraldo-Neto
- Laboratório de Bioquímica do Instituto Butantan, São Paulo 05503-900, Brazil
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16
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Palmer EE, Pusch M, Picollo A, Forwood C, Nguyen MH, Suckow V, Gibbons J, Hoff A, Sigfrid L, Megarbane A, Nizon M, Cogné B, Beneteau C, Alkuraya FS, Chedrawi A, Hashem MO, Stamberger H, Weckhuysen S, Vanlander A, Ceulemans B, Rajagopalan S, Nunn K, Arpin S, Raynaud M, Motter CS, Ward-Melver C, Janssens K, Meuwissen M, Beysen D, Dikow N, Grimmel M, Haack TB, Clement E, McTague A, Hunt D, Townshend S, Ward M, Richards LJ, Simons C, Costain G, Dupuis L, Mendoza-Londono R, Dudding-Byth T, Boyle J, Saunders C, Fleming E, El Chehadeh S, Spitz MA, Piton A, Gerard B, Abi Warde MT, Rea G, McKenna C, Douzgou S, Banka S, Akman C, Bain JM, Sands TT, Wilson GN, Silvertooth EJ, Miller L, Lederer D, Sachdev R, Macintosh R, Monestier O, Karadurmus D, Collins F, Carter M, Rohena L, Willemsen MH, Ockeloen CW, Pfundt R, Kroft SD, Field M, Laranjeira FER, Fortuna AM, Soares AR, Michaud V, Naudion S, Golla S, Weaver DD, Bird LM, Friedman J, Clowes V, Joss S, Pölsler L, Campeau PM, Blazo M, Bijlsma EK, Rosenfeld JA, Beetz C, Powis Z, McWalter K, Brandt T, Torti E, Mathot M, Mohammad SS, Armstrong R, Kalscheuer VM. Functional and clinical studies reveal pathophysiological complexity of CLCN4-related neurodevelopmental condition. Mol Psychiatry 2023; 28:668-697. [PMID: 36385166 PMCID: PMC9908558 DOI: 10.1038/s41380-022-01852-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 10/10/2022] [Accepted: 10/21/2022] [Indexed: 11/17/2022]
Abstract
Missense and truncating variants in the X-chromosome-linked CLCN4 gene, resulting in reduced or complete loss-of-function (LOF) of the encoded chloride/proton exchanger ClC-4, were recently demonstrated to cause a neurocognitive phenotype in both males and females. Through international clinical matchmaking and interrogation of public variant databases we assembled a database of 90 rare CLCN4 missense variants in 90 families: 41 unique and 18 recurrent variants in 49 families. For 43 families, including 22 males and 33 females, we collated detailed clinical and segregation data. To confirm causality of variants and to obtain insight into disease mechanisms, we investigated the effect on electrophysiological properties of 59 of the variants in Xenopus oocytes using extended voltage and pH ranges. Detailed analyses revealed new pathophysiological mechanisms: 25% (15/59) of variants demonstrated LOF, characterized by a "shift" of the voltage-dependent activation to more positive voltages, and nine variants resulted in a toxic gain-of-function, associated with a disrupted gate allowing inward transport at negative voltages. Functional results were not always in line with in silico pathogenicity scores, highlighting the complexity of pathogenicity assessment for accurate genetic counselling. The complex neurocognitive and psychiatric manifestations of this condition, and hitherto under-recognized impacts on growth, gastrointestinal function, and motor control are discussed. Including published cases, we summarize features in 122 individuals from 67 families with CLCN4-related neurodevelopmental condition and suggest future research directions with the aim of improving the integrated care for individuals with this diagnosis.
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Affiliation(s)
- Elizabeth E Palmer
- Centre for Clinical Genetics, Sydney Children's Hospital Network, Randwick, NSW, Australia.
- Discipline of Paediatrics and Child Health, Faculty of Medicine and Health, University of New South Wales, Randwick, NSW, Australia.
| | | | | | - Caitlin Forwood
- Centre for Clinical Genetics, Sydney Children's Hospital Network, Randwick, NSW, Australia
| | - Matthew H Nguyen
- Discipline of Paediatrics and Child Health, Faculty of Medicine and Health, University of New South Wales, Randwick, NSW, Australia
- Department of Clinical Genetics, Liverpool Hospital, Liverpool, NSW, Australia
| | - Vanessa Suckow
- Max Planck Institute for Molecular Genetics, Group Development and Disease, Berlin, Germany
| | - Jessica Gibbons
- Max Planck Institute for Molecular Genetics, Group Development and Disease, Berlin, Germany
| | - Alva Hoff
- Istituto di Biofisica, CNR, Genova, Italy
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, 581 83, Sweden
| | - Lisa Sigfrid
- Istituto di Biofisica, CNR, Genova, Italy
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, 581 83, Sweden
| | - Andre Megarbane
- Department of Human Genetics, Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Byblos, Lebanon
- Institut Jerome Lejeune, Paris, France
| | - Mathilde Nizon
- Service de Génétique Médicale, CHU de Nantes, Nantes Université, Nantes, France
- Nantes Université, CNRS, INSERM, l'Institut du Thorax, Nantes, France
| | - Benjamin Cogné
- Service de Génétique Médicale, CHU de Nantes, Nantes Université, Nantes, France
- Nantes Université, CNRS, INSERM, l'Institut du Thorax, Nantes, France
| | - Claire Beneteau
- Service de Génétique Médicale, CHU de Nantes, Nantes Université, Nantes, France
| | - Fowzan S Alkuraya
- Department of Translational Genomics, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Aziza Chedrawi
- Department of Neurosciences, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Mais O Hashem
- Department of Translational Genomics, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Hannah Stamberger
- Applied and Translational Neurogenomics Group, VIB Center for Molecular Neurology, VIB, Antwerp, Belgium
- Neurology Department, Antwerp University Hospital, Antwerp, Belgium
| | - Sarah Weckhuysen
- Applied and Translational Neurogenomics Group, VIB Center for Molecular Neurology, VIB, Antwerp, Belgium
- Neurology Department, Antwerp University Hospital, Antwerp, Belgium
- Translational Neurosciences, Faculty of Medicine and Health Science, University of Antwerp, Antwerp, Belgium
| | - Arnaud Vanlander
- Department of Child Neurology & Metabolism, Ghent University Hospital, Ghent, Belgium
| | - Berten Ceulemans
- Department of Pediatric Neurology, Antwerp University Hospital, University of Antwerp, Antwerp, Belgium
| | - Sulekha Rajagopalan
- Department of Clinical Genetics, Liverpool Hospital, Liverpool, NSW, Australia
| | - Kenneth Nunn
- Children's Hospital at Westmead, Sydney Children's Hospitals Network, Sydney, Australia
| | - Stéphanie Arpin
- Service de Génétique Clinique, Centre Hospitalier Régional Universitaire de Tours, Tours, France
| | - Martine Raynaud
- Service de Génétique Clinique, Centre Hospitalier Régional Universitaire de Tours, Tours, France
| | | | | | - Katrien Janssens
- Center of Medical Genetics, University Hospital Antwerp/University of Antwerp, Edegem, Belgium
| | - Marije Meuwissen
- Center of Medical Genetics, University Hospital Antwerp/University of Antwerp, Edegem, Belgium
| | - Diane Beysen
- Department of Pediatric Neurology, University Hospital Antwerp/University of Antwerp, Edegem, Belgium
| | - Nicola Dikow
- Institute of Human Genetics, Heidelberg University, Heidelberg, Germany
| | - Mona Grimmel
- Institute of Medical Genetics and Applied Genomics, University of Tuebingen, Tuebingen, Germany
| | - Tobias B Haack
- Institute of Medical Genetics and Applied Genomics, University of Tuebingen, Tuebingen, Germany
| | - Emma Clement
- Department of Clinical Genetics, Great Ormond Street Hospital for Children, London, UK
| | - Amy McTague
- Developmental Neurosciences, UCL Great Ormond Street Institute of Child Health, London, UK
- Department of Neurology, Great Ormond Street Hospital, London, UK
| | - David Hunt
- Wessex Clinical Genetics Service, Princess Anne Hospital, Southampton, UK
| | - Sharron Townshend
- Genetic Services of WA, King Edward Memorial Hospital, Subiaco, WA, Australia
| | - Michelle Ward
- Genetic Services of WA, King Edward Memorial Hospital, Subiaco, WA, Australia
| | - Linda J Richards
- Department of Neuroscience, Washington University in St Louis School of Medicine, St Louis, MI, USA
- The University of Queensland, Queensland Brain Institute, St Lucia, QLD, Australia
| | - Cas Simons
- Centre for Population Genomics, Murdoch Children's Research Institute, Melbourne, Australia
- Garvan Institute of Medical Research, UNSW, Sydney, NSW, Australia
| | - Gregory Costain
- Division of Clinical and Metabolic Genetics, The Hospital for Sick Children, Toronto, ON, Canada
| | - Lucie Dupuis
- Division of Clinical and Metabolic Genetics, The Hospital for Sick Children, Toronto, ON, Canada
| | - Roberto Mendoza-Londono
- Division of Clinical and Metabolic Genetics, The Hospital for Sick Children, Toronto, ON, Canada
| | - Tracy Dudding-Byth
- Genetics of Learning Disability Service, Newcastle, NSW, Australia
- University of Newcastle Grow Up Well Priority Research Centre, Newcastle, NSW, Australia
| | - Jackie Boyle
- Genetics of Learning Disability Service, Newcastle, NSW, Australia
| | - Carol Saunders
- Department of Pathology and Laboratory Medicine, Children's Mercy Hospital and Clinics, MI, Kansas City, USA
- Kansas City School of Medicine, University of Missouri, Kansas City, MI, USA
| | - Emily Fleming
- Division of Clinical Genetics, Children's Mercy Hospital and Clinics, Kansas City, MI, USA
| | - Salima El Chehadeh
- Service de Génétique Médicale, Institut de Génétique Médicale d'Alsace (IGMA), Hôpitaux Universitaires de Strasbourg, Strasbourg, France
- Laboratoire de Génétique Médicale, UMRS_1112, Institut de Génétique Médicale d'Alsace (IGMA), Université de Strasbourg et INSERM, Strasbourg, France
| | - Marie-Aude Spitz
- Service de Pédiatrie, Hôpital de Hautepierre, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - Amelie Piton
- Laboratoires de Diagnostic Génétique, Institut de Génétique Médicale d'Alsace (IGMA), Hôpitaux Universitaires de Strasbourg, Nouvel Hôpital Civil, Strasbourg, France
| | - Bénédicte Gerard
- Laboratoires de Diagnostic Génétique, Institut de Génétique Médicale d'Alsace (IGMA), Hôpitaux Universitaires de Strasbourg, Nouvel Hôpital Civil, Strasbourg, France
| | - Marie-Thérèse Abi Warde
- Service de Pédiatrie, Hôpital de Hautepierre, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
- Pediatric Neurology Department, CHU de Strasbourg, Strasbourg, France
| | - Gillian Rea
- Northern Ireland Regional Genetics Service, Belfast, Northern Ireland
| | - Caoimhe McKenna
- Northern Ireland Regional Genetics Service, Belfast, Northern Ireland
| | - Sofia Douzgou
- Department of Medical Genetics, Haukeland University Hospital, Bergen, Norway
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Siddharth Banka
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
- Manchester Centre for Genomic Medicine, Saint Mary's Hospital, Manchester University NHS Foundation Trust, Manchester, UK
| | - Cigdem Akman
- Department of Neurology, Division of Child Neurology, Columbia University Irving Medical Center, New York, USA
| | - Jennifer M Bain
- Department of Neurology, Division of Child Neurology, Columbia University Irving Medical Center, New York, USA
| | - Tristan T Sands
- Department of Neurology, Division of Child Neurology, Columbia University Irving Medical Center, New York, USA
| | - Golder N Wilson
- Texas Tech Health Sciences Center Lubbock and KinderGenome Medical Genetics, Dallas, TX, USA
| | | | | | - Damien Lederer
- Centre de Génétique Humaine, Institut de Pathologie et de Génétique ASBL, Gosselies, Belgium
| | - Rani Sachdev
- Centre for Clinical Genetics, Sydney Children's Hospital Network, Randwick, NSW, Australia
- Discipline of Paediatrics and Child Health, Faculty of Medicine and Health, University of New South Wales, Randwick, NSW, Australia
| | - Rebecca Macintosh
- Centre for Clinical Genetics, Sydney Children's Hospital Network, Randwick, NSW, Australia
- Discipline of Paediatrics and Child Health, Faculty of Medicine and Health, University of New South Wales, Randwick, NSW, Australia
| | - Olivier Monestier
- Centre de Génétique Humaine, Institut de Pathologie et de Génétique ASBL, Gosselies, Belgium
| | - Deniz Karadurmus
- Centre de Génétique Humaine, Institut de Pathologie et de Génétique ASBL, Gosselies, Belgium
| | - Felicity Collins
- Department of Medical Genomics/Clinical Genetics, Royal Prince Alfred Hospital, Camperdown, Sydney, NSW, Australia
| | - Melissa Carter
- Department of Genetics, Children's Hospital of Eastern Ontario, Ottawa, ON, Canada
| | - Luis Rohena
- Division of Medical Genetics, Department of Pediatrics, San Antonio Military Medical Center, San Antonio, TX, USA
- Department of Pediatrics, Long School of Medicine-UT Health San Antonio, San Antonio, TX, USA
| | - Marjolein H Willemsen
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Charlotte W Ockeloen
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Rolph Pfundt
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Sanne D Kroft
- Pluryn, Residential Care Setting, Groesbeek, The Netherlands
| | - Michael Field
- Genetics of Learning Disability Service, Newcastle, NSW, Australia
| | - Francisco E R Laranjeira
- Centro de Genética Médica Jacinto Magalhães, Centro Hospitalar Universitário do Porto, Porto, Portugal
| | - Ana M Fortuna
- Unit for Multidisciplinary Research in Biomedicine, School of Medicine and Biomedical Sciences, Porto University, Porto, Portugal
| | - Ana R Soares
- Unit for Multidisciplinary Research in Biomedicine, School of Medicine and Biomedical Sciences, Porto University, Porto, Portugal
| | - Vincent Michaud
- Service de Génétique Médicale, CHU Bordeaux, Bordeaux, France
- INSERM U1211, Laboratoire Maladies Rares: Génétique et Métabolisme, Bordeaux, Univ., Bordeaux, France
| | - Sophie Naudion
- Service de Génétique Médicale, CHU Bordeaux, Bordeaux, France
| | - Sailaja Golla
- Child Neurology and Neurodevelopmental Medicine Thompson Autism Center, CHOC Hospital, Orange County, CA, USA
| | - David D Weaver
- Indiana University School of Medicine, Indianapolis, USA
| | - Lynne M Bird
- University of California, San Diego, Rady Children's Hospital San Diego, San Diego, CA, USA
| | - Jennifer Friedman
- University of California, San Diego, Rady Children's Hospital San Diego, San Diego, CA, USA
| | - Virginia Clowes
- North West Thames Regional Genetics Service, London North West University Healthcare NHS Trust, Harrow, London, UK
- Imperial College London, London, UK
| | - Shelagh Joss
- West of Scotland Centre for Genomic Medicine, Queen Elizabeth University Hospital, Glasgow, UK
| | - Laura Pölsler
- Centrum Medische Genetica, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Philippe M Campeau
- CHU Sainte-Justine Research Center, University of Montreal, Montreal, QC, Canada
| | - Maria Blazo
- Division Clinical Genetics Texas A&M University Health Science Center, College Station, TX, USA
| | - Emilia K Bijlsma
- Department of Clinical Genetics, Leiden University Medical Centre, Leiden, The Netherlands
| | - Jill A Rosenfeld
- Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
- Baylor Genetics Laboratories, Houston, TX, USA
| | | | - Zöe Powis
- Clinical Genomics, Ambry Genetics, Aliso Viejo, CA, USA
| | | | | | | | | | - Shekeeb S Mohammad
- Children's Hospital at Westmead, Sydney Children's Hospitals Network, Sydney, Australia
- Children's Hospital at Westmead, Sydney Children's Hospitals Network, Sydney, NSW, Australia
| | - Ruth Armstrong
- East Anglian Medical Genetics Service, Clinical Genetics, Addenbrooke's Treatment Centre, Addenbrooke's Hospital, Cambridge, UK
| | - Vera M Kalscheuer
- Max Planck Institute for Molecular Genetics, Group Development and Disease, Berlin, Germany.
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17
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Lepiarczyk E, Paukszto Ł, Wiszpolska M, Łopieńska-Biernat E, Bossowska A, Majewski MK, Majewska M. Molecular Influence of Resiniferatoxin on the Urinary Bladder Wall Based on Differential Gene Expression Profiling. Cells 2023; 12:cells12030462. [PMID: 36766804 PMCID: PMC9914288 DOI: 10.3390/cells12030462] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 01/25/2023] [Accepted: 01/27/2023] [Indexed: 02/04/2023] Open
Abstract
Resiniferatoxin (RTX) is a potent capsaicin analog used as a drug for experimental therapy to treat neurogenic disorders associated with enhanced nociceptive transmission, including lower urinary tract symptoms. The present study, for the first time, investigated the transcriptomic profile of control and RTX-treated porcine urinary bladder walls. We applied multistep bioinformatics and discovered 129 differentially expressed genes (DEGs): 54 upregulated and 75 downregulated. Metabolic pathways analysis revealed five significant Kyoto Encyclopedia of Genes and Genomes (KEGG) items ('folate biosynthesis', 'metabolic pathways', 'sulfur relay system', 'sulfur metabolism' and 'serotonergic synapse') that were altered after RTX intravesical administration. A thorough analysis of the detected DEGs indicated that RTX treatment influenced the signaling pathways regulating nerve growth, myelination, axon specification, and elongation. Many of the revealed DEGs are involved in the nerve degeneration process; however, some of them were implicated in the initiation of neuroprotective mechanisms. Interestingly, RTX intravesical installation was followed by changes in the expression of genes involved in synaptic plasticity and neuromodulation, including 5-HT, H2S, glutamate, and GABA transmission. The obtained results suggest that the toxin may exert a therapeutic, antinociceptive effect not only by acting on TRPV1 receptors.
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Affiliation(s)
- Ewa Lepiarczyk
- Department of Human Physiology and Pathophysiology, School of Medicine, Collegium Medicum, University of Warmia and Mazury in Olsztyn, 10-082 Olsztyn, Poland
- Correspondence: ; Tel.: +48-89-524-53-34; Fax: +48-89-524-53-07
| | - Łukasz Paukszto
- Department of Botany and Nature Protection, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, 10-727 Olsztyn, Poland
| | - Marta Wiszpolska
- Department of Human Physiology and Pathophysiology, School of Medicine, Collegium Medicum, University of Warmia and Mazury in Olsztyn, 10-082 Olsztyn, Poland
| | - Elżbieta Łopieńska-Biernat
- Department of Biochemistry, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland
| | - Agnieszka Bossowska
- Department of Human Physiology and Pathophysiology, School of Medicine, Collegium Medicum, University of Warmia and Mazury in Olsztyn, 10-082 Olsztyn, Poland
| | - Mariusz Krzysztof Majewski
- Department of Human Physiology and Pathophysiology, School of Medicine, Collegium Medicum, University of Warmia and Mazury in Olsztyn, 10-082 Olsztyn, Poland
| | - Marta Majewska
- Department of Human Physiology and Pathophysiology, School of Medicine, Collegium Medicum, University of Warmia and Mazury in Olsztyn, 10-082 Olsztyn, Poland
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18
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Kisaretova P, Tsybko A, Bondar N, Reshetnikov V. Molecular Abnormalities in BTBR Mice and Their Relevance to Schizophrenia and Autism Spectrum Disorders: An Overview of Transcriptomic and Proteomic Studies. Biomedicines 2023; 11:289. [PMID: 36830826 PMCID: PMC9953015 DOI: 10.3390/biomedicines11020289] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 01/17/2023] [Accepted: 01/18/2023] [Indexed: 01/22/2023] Open
Abstract
Animal models of psychopathologies are of exceptional interest for neurobiologists because these models allow us to clarify molecular mechanisms underlying the pathologies. One such model is the inbred BTBR strain of mice, which is characterized by behavioral, neuroanatomical, and physiological hallmarks of schizophrenia (SCZ) and autism spectrum disorders (ASDs). Despite the active use of BTBR mice as a model object, the understanding of the molecular features of this strain that cause the observed behavioral phenotype remains insufficient. Here, we analyzed recently published data from independent transcriptomic and proteomic studies on hippocampal and corticostriatal samples from BTBR mice to search for the most consistent aberrations in gene or protein expression. Next, we compared reproducible molecular signatures of BTBR mice with data on postmortem samples from ASD and SCZ patients. Taken together, these data helped us to elucidate brain-region-specific molecular abnormalities in BTBR mice as well as their relevance to the anomalies seen in ASDs or SCZ in humans.
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Affiliation(s)
- Polina Kisaretova
- Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, Prospekt Akad. Lavrentyeva 10, Novosibirsk 630090, Russia
- Department of Natural Sciences, Novosibirsk State University, Pirogova Street 2, Novosibirsk 630090, Russia
| | - Anton Tsybko
- Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, Prospekt Akad. Lavrentyeva 10, Novosibirsk 630090, Russia
| | - Natalia Bondar
- Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, Prospekt Akad. Lavrentyeva 10, Novosibirsk 630090, Russia
| | - Vasiliy Reshetnikov
- Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, Prospekt Akad. Lavrentyeva 10, Novosibirsk 630090, Russia
- Department of Biotechnology, Sirius University of Science and Technology, 1 Olympic Avenue, Sochi 354340, Russia
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19
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Sierra-Marquez J, Willuweit A, Schöneck M, Bungert-Plümke S, Gehlen J, Balduin C, Müller F, Lampert A, Fahlke C, Guzman RE. ClC-3 regulates the excitability of nociceptive neurons and is involved in inflammatory processes within the spinal sensory pathway. Front Cell Neurosci 2022; 16:920075. [PMID: 37124866 PMCID: PMC10134905 DOI: 10.3389/fncel.2022.920075] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 07/28/2022] [Indexed: 11/13/2022] Open
Abstract
ClC-3 Cl–/H+ exchangers are expressed in multiple endosomal compartments and likely modify intra-endosomal pH and [Cl–] via the stoichiometrically coupled exchange of two Cl– ions and one H+. We studied pain perception in Clcn3–/– mice and found that ClC-3 not only modifies the electrical activity of peripheral nociceptors but is also involved in inflammatory processes in the spinal cord. We demonstrate that ClC-3 regulates the number of Nav and Kv ion channels in the plasma membrane of dorsal root ganglion (DRG) neurons and that these changes impair the age-dependent decline in excitability of sensory neurons. To distinguish the role of ClC-3 in Cl–/H+ exchange from its other functions in pain perception, we used mice homozygous for the E281Q ClC-3 point mutation (Clcn3E281Q/E281Q), which completely eliminates transport activity. Since ClC-3 forms heterodimers with ClC-4, we crossed these animals with Clcn4–/– to obtain mice completely lacking in ClC-3-associated endosomal chloride–proton transport. The electrical properties of Clcn3E281Q/E281Q/Clcn4–/– DRG neurons were similar to those of wild-type cells, indicating that the age-dependent adjustment of neuronal excitability is independent of ClC-3 transport activity. Both Clcn3–/– and Clcn3E281Q/E281Q/Clcn4–/– animals exhibited microglial activation in the spinal cord, demonstrating that competent ClC-3 transport is needed to maintain glial cell homeostasis. Our findings illustrate how reduced Cl–/H+ exchange contributes to inflammatory responses and demonstrate a role for ClC-3 in the homeostatic regulation of neuronal excitability beyond its function in endosomal ion balance.
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Affiliation(s)
- Juan Sierra-Marquez
- Institute of Biological Information Processing, Molecular and Cellular Physiology (IBI-1), Forschungszentrum Jülich, Jülich, Germany
| | - Antje Willuweit
- Medical Imaging Physics, Institute of Neuroscience and Medicine (INM-4), Forschungszentrum Jülich, Jülich, Germany
| | - Michael Schöneck
- Medical Imaging Physics, Institute of Neuroscience and Medicine (INM-4), Forschungszentrum Jülich, Jülich, Germany
| | - Stefanie Bungert-Plümke
- Institute of Biological Information Processing, Molecular and Cellular Physiology (IBI-1), Forschungszentrum Jülich, Jülich, Germany
| | - Jana Gehlen
- Institute of Biological Information Processing, Molecular and Cellular Physiology (IBI-1), Forschungszentrum Jülich, Jülich, Germany
| | - Carina Balduin
- Medical Imaging Physics, Institute of Neuroscience and Medicine (INM-4), Forschungszentrum Jülich, Jülich, Germany
| | - Frank Müller
- Institute of Biological Information Processing, Molecular and Cellular Physiology (IBI-1), Forschungszentrum Jülich, Jülich, Germany
| | | | - Christoph Fahlke
- Institute of Biological Information Processing, Molecular and Cellular Physiology (IBI-1), Forschungszentrum Jülich, Jülich, Germany
| | - Raul E. Guzman
- Institute of Biological Information Processing, Molecular and Cellular Physiology (IBI-1), Forschungszentrum Jülich, Jülich, Germany
- *Correspondence: Raul E. Guzman,
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20
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Klemens CA, Dissanayake LV, Levchenko V, Zietara A, Palygin O, Staruschenko A. Modulation of blood pressure regulatory genes in the Agtrap-Plod1 locus associated with a deletion in Clcn6. Physiol Rep 2022; 10:e15417. [PMID: 35927940 PMCID: PMC9353118 DOI: 10.14814/phy2.15417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 07/15/2022] [Accepted: 07/18/2022] [Indexed: 06/15/2023] Open
Abstract
The AGTRAP-PLOD1 locus is a conserved gene cluster containing several blood pressure regulatory genes, including CLCN6, MTHFR, NPPA, and NPPB. Previous work revealed that knockout of Clcn6 on the Dahl Salt-Sensitive (SS) rat background (SS-Clcn6) resulted in lower diastolic blood pressure compared to SS-WT rats. Additionally, a recent study found sickle cell anemia patients with mutations in CLCN6 had improved survival and reduced stroke risk. We investigated whether loss of Clcn6 would delay the mortality of Dahl SS rats on an 8% NaCl (HS) diet. No significant difference in survival was found. The ability of Clcn6 to affect mRNA expression of nearby Mthfr, Nppa, and Nppb genes was also tested. On normal salt (0.4% NaCl, NS) diets, renal Mthfr mRNA and protein expression were significantly increased in the SS-Clcn6 rats. MTHFR reduces homocysteine to methionine, but no differences in circulating homocysteine levels were detected. Nppa mRNA levels in cardiac tissue from SS-Clcn6 rat in both normotensive and hypertensive conditions were significantly reduced compared to SS-WT. Nppb mRNA expression in SS-Clcn6 rats on a NS diet was also substantially decreased. Heightened Mthfr expression would be predicted to be protective; however, diminished Nppa and Nppb expression could be deleterious and by preventing or blunting vasodilation, natriuresis, and diuresis that ought to normally occur to offset blood pressure increases. The conserved nature of this genetic locus in humans and rats suggests more studies are warranted to understand how mutations in and around these genes may be influencing the expression of their neighbors.
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Affiliation(s)
- Christine A. Klemens
- Department of Molecular Pharmacology and PhysiologyUniversity of South FloridaTampaFloridaUSA
- Hypertension and Kidney Research CenterUniversity of South FloridaTampaFloridaUSA
| | - Lashodya V. Dissanayake
- Department of Molecular Pharmacology and PhysiologyUniversity of South FloridaTampaFloridaUSA
- Department of PhysiologyMedical College of WisconsinMilwaukeeWisconsinUSA
| | - Vladislav Levchenko
- Department of Molecular Pharmacology and PhysiologyUniversity of South FloridaTampaFloridaUSA
| | - Adrian Zietara
- Department of Molecular Pharmacology and PhysiologyUniversity of South FloridaTampaFloridaUSA
- Department of PhysiologyMedical College of WisconsinMilwaukeeWisconsinUSA
| | - Oleg Palygin
- Department of MedicineMedical University of South CarolinaCharlestonSouth CarolinaUSA
| | - Alexander Staruschenko
- Department of Molecular Pharmacology and PhysiologyUniversity of South FloridaTampaFloridaUSA
- Hypertension and Kidney Research CenterUniversity of South FloridaTampaFloridaUSA
- James A. Haley Veterans' HospitalTampaFloridaUSA
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21
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Bullock G, Johnson GS, Mhlanga-Mutangadura T, Petesch SC, Thompson S, Goebbels S, Katz ML. Lysosomal storage disease associated with a CNP sequence variant in Dalmatian dogs. Gene X 2022; 830:146513. [PMID: 35447247 DOI: 10.1016/j.gene.2022.146513] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 03/31/2022] [Accepted: 04/14/2022] [Indexed: 11/04/2022] Open
Abstract
A progressive neurological disorder was identified in purebred Dalmatian dogs. The disease is characterized by anxiety, pacing and circling, hypersensitivity, cognitive decline, sleep disturbance, loss of coordination, loss of control over urination and defecation, and visual impairment. Neurological signs first became apparent when the dogs were approximately 18 months of age and progressed slowly. Two affected littermates were euthanized at approximately 7 years, 5 months and 8 years, 2 months of age due to the severity of neurological impairment. The mother of the affected dogs and four other relatives exhibited milder, later-onset neurological signs. Pronounced accumulations of autofluorescent intracellular inclusions were found in cerebral cortex, cerebellum, optic nerve, and cardiac muscle of the affected dogs. These inclusions co-localized with immunolabeling of the lysosomal marker protein LAMP2 and bound antibodies to mitochondrial ATPase subunit c, indicating that the dogs suffered from a lysosomal storage disease with similarities to the neuronal ceroid lipofuscinoses. Ultrastructural analysis indicated that the storage bodies were surrounded by a single-layer membrane, but the storage granules were distinct from those reported for other lysosomal storage diseases. Whole genome sequences, generated with DNA from the two euthanized Dalmatians, both contained a rare, homozygous single-base deletion and reading-frame shift in CNP which encodes the enzyme CNPase (EC 3.1.4.37). The late-onset disease was exhibited by five of seven related Dalmatians that were heterozygous for the deletion allele and over 8 years of age, whereas none of 16 age-matched reference-allele homozygotes developed neurologic signs. No CNPase antigen could be detected with immunohistochemical labeling in tissues from the dogs with the earlier-onset disorder. Similar to the later-onset Dalmatians, autofluorescent storage granules were apparent in brain and cardiac tissue from transgenic mice that were nullizygous for Cnp. Based on the clinical signs, the histopathological, immunohistochemical, ultrastructural, and molecular-genetic findings, and the finding that nullizygous Cnp mice accumulate autofluorescent storage granules, we propose that the earlier-onset Dalmatian disorder is a novel lysosomal storage disease that results from a loss-of-function mutation in CNP and that shares features characteristic of the neuronal ceroid lipofuscinoses. That the later-onset disorder occurred only in dogs heterozygous for the CNP deletion variant suggests that this disorder is a result of the variant allele's presence.
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Affiliation(s)
- Garrett Bullock
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA
| | - Gary S Johnson
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA
| | - Tendai Mhlanga-Mutangadura
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA
| | - Scott C Petesch
- University of Pennsylvania School of Veterinary Medicine, Philadelphia, PA, USA
| | | | - Sandra Goebbels
- Max Planck Institute of Experimental Medicine, Department of Neurogenetics, Hermann-Rein-Str. 3, 37075 Göttingen, Germany
| | - Martin L Katz
- Neurodegenerative Diseases Research Laboratory, University of Missouri School of Medicine, Columbia, MO, USA.
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22
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Guzman RE, Sierra-Marquez J, Bungert-Plümke S, Franzen A, Fahlke C. Functional Characterization of CLCN4 Variants Associated With X-Linked Intellectual Disability and Epilepsy. Front Mol Neurosci 2022; 15:872407. [PMID: 35721313 PMCID: PMC9198718 DOI: 10.3389/fnmol.2022.872407] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 04/27/2022] [Indexed: 11/13/2022] Open
Abstract
Early/late endosomes, recycling endosomes, and lysosomes together form the endo-lysosomal recycling pathway. This system plays a crucial role in cell differentiation and survival, and dysregulation of the endo-lysosomal system appears to be important in the pathogenesis of neurodevelopmental and neurodegenerative diseases. Each endo-lysosomal compartment fulfils a specific function, which is supported by ion transporters and channels that modify ion concentrations and electrical gradients across endo-lysosomal membranes. CLC-type Cl–/H+ exchangers are a group of endo-lysosomal transporters that are assumed to regulate luminal acidification and chloride concentration in multiple endosomal compartments. Heterodimers of ClC-3 and ClC-4 localize to various internal membranes, from the endoplasmic reticulum and Golgi to recycling endosomes and late endosomes/lysosomes. The importance of ClC-4-mediated ion transport is illustrated by the association of naturally occurring CLCN4 mutations with epileptic encephalopathy, intellectual disability, and behavioral disorders in human patients. However, how these mutations affect the expression, subcellular localization, and function of ClC-4 is insufficiently understood. We here studied 12 CLCN4 variants that were identified in patients with X-linked intellectual disability and epilepsy and were already characterized to some extent in earlier work. We analyzed the consequences of these mutations on ClC-4 ion transport, subcellular trafficking, and heterodimerization with ClC-3 using heterologous expression in mammalian cells, biochemistry, confocal imaging, and whole-cell patch-clamp recordings. The mutations led to a variety of changes in ClC-4 function, ranging from gain/loss of function and impaired heterodimerization with ClC-3 to subtle impairments in transport functions. Our results suggest that even slight functional changes to the endosomal Cl–/H+ exchangers can cause serious neurological symptoms.
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23
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Zeziulia M, Blin S, Schmitt FW, Lehmann M, Jentsch TJ. Proton-gated anion transport governs macropinosome shrinkage. Nat Cell Biol 2022; 24:885-895. [PMID: 35590106 PMCID: PMC9203271 DOI: 10.1038/s41556-022-00912-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 04/05/2022] [Indexed: 01/25/2023]
Abstract
Intracellular organelles change their size during trafficking and maturation. This requires the transport of ions and water across their membranes. Macropinocytosis, a ubiquitous form of endocytosis of particular importance for immune and cancer cells, generates large vacuoles that can be followed optically. Shrinkage of macrophage macropinosomes depends on TPC-mediated Na+ efflux and Cl− exit through unknown channels. Relieving osmotic pressure facilitates vesicle budding, positioning osmotic shrinkage upstream of vesicular sorting and trafficking. Here we identify the missing macrophage Cl− channel as the proton-activated Cl− channel ASOR/TMEM206. ASOR activation requires Na+-mediated depolarization and luminal acidification by redundant transporters including H+-ATPases and CLC 2Cl−/H+ exchangers. As corroborated by mathematical modelling, feedback loops requiring the steep voltage and pH dependencies of ASOR and CLCs render vacuole resolution resilient towards transporter copy numbers. TMEM206 disruption increased albumin-dependent survival of cancer cells. Our work suggests a function for the voltage and pH dependence of ASOR and CLCs, provides a comprehensive model for ion-transport-dependent vacuole maturation and reveals biological roles of ASOR. Zeziulia et al. identify the proton-activated Cl− channel ASOR/TMEM206 as necessary for shrinkage of macropinosomes, which is needed for downstream sorting events.
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Affiliation(s)
- Mariia Zeziulia
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany.,Max-Delbrück-Centrum für Molekulare Medizin (MDC), Berlin, Germany.,Graduate Program of the Freie Universität Berlin, Berlin, Germany
| | - Sandy Blin
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany.,Max-Delbrück-Centrum für Molekulare Medizin (MDC), Berlin, Germany
| | - Franziska W Schmitt
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany.,Max-Delbrück-Centrum für Molekulare Medizin (MDC), Berlin, Germany.,Graduate Program of the Humboldt Universität Berlin, Berlin, Germany
| | - Martin Lehmann
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany
| | - Thomas J Jentsch
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany. .,Max-Delbrück-Centrum für Molekulare Medizin (MDC), Berlin, Germany. .,NeuroCure Cluster of Excellence, Charité Universitätsmedizin, Berlin, Germany.
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24
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Kobertz WR. Want to hear ClC-6 sing? Push your amp to eleven. J Physiol 2022; 600:2019-2020. [PMID: 35286714 DOI: 10.1113/jp283060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- William R Kobertz
- Department of Biochemistry and Molecular Pharmacology, Programs in Neuroscience and Chemical Biology, UMass Chan Medical School, 364 Plantation Street, Worcester, MA, 01605-2324
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25
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Zifarelli G, Pusch M, Fong P. Altered voltage-dependence of slowly activating chloride-proton antiport by late endosomal ClC-6 explains distinct neurological disorders. J Physiol 2022; 600:2147-2164. [PMID: 35262198 DOI: 10.1113/jp282737] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 03/01/2022] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS Ionic composition and pH within intracellular compartments, such as endo-lysosomes, rely on the activity of chloride/proton transporters including ClC-6. Distinct CLCN6 mutations previously were found in individuals with neurodegenerative disease, and also putatively associated with neuronal ceroidal lipofuscinosis. Limited knowledge of wild-type ClC-6 transport function impedes understanding of mechanisms underlying these conditions. We resolved transient and transport currents that permit measurement of voltage- and pH- dependences, as well as kinetics, for wild-type and disease-associated mutant ClC-6s. These findings define wild-type ClC-6 function robustly, and reveal how alterations of the slow activation gating of the transporter cause different kinds of neurological diseases. ABSTRACT ClC-6 is an intracellularly localized member of the CLC family of chloride transport proteins. It presumably functions in the endo-lysosomal compartment as a chloride-proton antiporter, despite a paucity of biophysical studies in direct support. Observations of lysosomal storage disease, as well as neurodegenerative disorders, emerge with its disruption by knockout or mutation, respectively. An incomplete understanding of wild type ClC-6 function obscures clear mechanistic insight into disease etiology. Here, high-resolution recording protocols that incorporate extreme voltage pulses permit detailed biophysical measurement and analysis of transient capacitive, as well as ionic transport currents. This approach reveals that wild type ClC-6 activation and transport require depolarization to voltages beyond 140 mV. Mutant Y553C associated with early-onset neurodegeneration exerts gain-of-function by shifting the half-maximal voltage for activation to less depolarized voltages. Moreover, we show that the E267A proton glutamate mutant conserves transport currents, albeit reduced. Lastly, the positive shift in activation voltage shown by V580M, a mutant identified in a patient with late- onset lysosomal storage disease, can explain loss-of-function leading to disease. Abstract figure legend CLC transport proteins comprise both channels and transporters. Vesicular CLC transporters function to regulate compartmental ionic homeostasis and acidification. ClC-6 is a vesicular CLC that localizes to the endo-lysosomal compartment. Functional plasma membrane overexpression of GFP-tagged ClC-6 in HEK293 cells surmounted spatial inaccessibility, and rapid whole cell patch recording protocols enabling resolution of fast capacitive transients, as well as ionic transport currents, provided details of wild-type ClC-6 biophysical properties including voltage-dependence, pH-dependence, and kinetics. Clearly defined wild-type ClC-6 function permitted subsequent comparative analysis of mutants, including but not limited to those pertinent to disease. These range from one causing severe, early-onset neurodegeneration, to two variants previously identified in Kufs disease, a late-onset lysosomal storage disease characterized by neuronal ceroid lipofuscinosis. These findings further inform models whereby disruption of ClC-6 biophysical properties set the stage for dysregulated compartmental homeostasis and hence, disease. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Giovanni Zifarelli
- Institute of Biophysics, CNR, Genoa, Italy.,Present address: Centogene GmbH, Rostock, Germany
| | | | - Peying Fong
- Department of Anatomy and Physiology, Kansas State University College of Veterinary Medicine, Manhattan, KS, USA
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26
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Baxter LL, Watkins-Chow DE, Johnson NL, Farhat NY, Platt FM, Dale RK, Porter FD, Pavan WJ, Rodriguez-Gil JL. Correlation of age of onset and clinical severity in Niemann-Pick disease type C1 with lysosomal abnormalities and gene expression. Sci Rep 2022; 12:2162. [PMID: 35140266 PMCID: PMC8828765 DOI: 10.1038/s41598-022-06112-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 01/18/2022] [Indexed: 11/08/2022] Open
Abstract
Niemann-Pick disease type C1 (NPC1) is a rare, prematurely fatal lysosomal storage disorder which exhibits highly variable severity and disease progression as well as a wide-ranging age of onset, from perinatal stages to adulthood. This heterogeneity has made it difficult to obtain prompt diagnosis and to predict disease course. In addition, small NPC1 patient sample sizes have been a limiting factor in acquiring genome-wide transcriptome data. In this study, primary fibroblasts from an extensive cohort of 41 NPC1 patients were used to validate our previous findings that the lysosomal quantitative probe LysoTracker can be used as a predictor for age of onset and disease severity. We also examined the correlation between these clinical parameters and RNA expression data from primary fibroblasts and identified a set of genes that were significantly associated with lysosomal defects or age of onset, in particular neurological symptom onset. Hierarchical clustering showed that these genes exhibited distinct expression patterns among patient subgroups. This study is the first to collect transcriptomic data on such a large scale in correlation with clinical and cellular phenotypes, providing a rich genomic resource to address NPC1 clinical heterogeneity and discover potential biomarkers, disease modifiers, or therapeutic targets.
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Affiliation(s)
- Laura L Baxter
- Genomics, Development and Disease Section, Genetic Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Dawn E Watkins-Chow
- Genomics, Development and Disease Section, Genetic Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Nicholas L Johnson
- Bioinformatics and Scientific Programming Core, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Nicole Y Farhat
- Division of Translational Medicine, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Frances M Platt
- Department of Pharmacology, University of Oxford, Oxford, UK
| | - Ryan K Dale
- Bioinformatics and Scientific Programming Core, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Forbes D Porter
- Division of Translational Medicine, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - William J Pavan
- Genomics, Development and Disease Section, Genetic Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA.
| | - Jorge L Rodriguez-Gil
- Genomics, Development and Disease Section, Genetic Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA.
- Division of Medical Genetics, Stanford University School of Medicine, Stanford, CA, USA.
- Department of Pediatrics, Stanford University School of Medicine, Stanford, CA, USA.
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27
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The Role of the Lysosomal Cl−/H+ Antiporter ClC-7 in Osteopetrosis and Neurodegeneration. Cells 2022; 11:cells11030366. [PMID: 35159175 PMCID: PMC8833911 DOI: 10.3390/cells11030366] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 01/16/2022] [Accepted: 01/19/2022] [Indexed: 12/04/2022] Open
Abstract
CLC proteins comprise Cl− channels and anion/H+ antiporters involved in several fundamental physiological processes. ClC-7 is a lysosomal Cl−/H+ antiporter that together with its beta subunit Ostm1 has a critical role in the ionic homeostasis of lysosomes and of the osteoclasts’ resorption lacuna, although the specific underlying mechanism has so far remained elusive. Mutations in ClC-7 cause osteopetrosis, but also a form of lysosomal storage disease and neurodegeneration. Interestingly, both loss-of- and gain-of-function mutations of ClC-7 can be pathogenic, but the mechanistic implications of this finding are still unclear. This review will focus on the recent advances in our understanding of the biophysical properties of ClC-7 and of its role in human diseases with a focus on osteopetrosis and neurodegeneration.
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28
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Gardner E, Mole SE. The Genetic Basis of Phenotypic Heterogeneity in the Neuronal Ceroid Lipofuscinoses. Front Neurol 2021; 12:754045. [PMID: 34733232 PMCID: PMC8558747 DOI: 10.3389/fneur.2021.754045] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 09/20/2021] [Indexed: 12/12/2022] Open
Abstract
The neuronal ceroid lipofuscinoses (NCLs) are a group of inherited neurodegenerative disorders that affect children and adults. They share some similar clinical features and the accumulation of autofluorescent storage material. Since the discovery of the first causative genes, more than 530 mutations have been identified across 13 genes in cases diagnosed with NCL. These genes encode a variety of proteins whose functions have not been fully defined; most are lysosomal enzymes, or transmembrane proteins of the lysosome or other organelles. Many mutations in these genes are associated with a typical NCL disease phenotype. However, increasing numbers of variant disease phenotypes are being described, affecting age of onset, severity or progression, and including some distinct clinical phenotypes. This data is collated by the NCL Mutation Database which allows analysis from many perspectives. This article will summarise and interpret current knowledge and understanding of their genetic basis and phenotypic heterogeneity.
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Affiliation(s)
- Emily Gardner
- MRC Laboratory for Molecular Cell Biology and Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
| | - Sara E Mole
- MRC Laboratory for Molecular Cell Biology and Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
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29
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Duncan AR, Polovitskaya MM, Gaitán-Peñas H, Bertelli S, VanNoy GE, Grant PE, O’Donnell-Luria A, Valivullah Z, Lovgren AK, England EM, Agolini E, Madden JA, Schmitz-Abe K, Kritzer A, Hawley P, Novelli A, Alfieri P, Colafati GS, Wieczorek D, Platzer K, Luppe J, Koch-Hogrebe M, Abou Jamra R, Neira-Fresneda J, Lehman A, Boerkoel CF, Seath K, Clarke L, van Ierland Y, Argilli E, Sherr EH, Maiorana A, Diel T, Hempel M, Bierhals T, Estévez R, Jentsch TJ, Pusch M, Agrawal PB, Agrawal PB. Unique variants in CLCN3, encoding an endosomal anion/proton exchanger, underlie a spectrum of neurodevelopmental disorders. Am J Hum Genet 2021; 108:1450-1465. [PMID: 34186028 DOI: 10.1016/j.ajhg.2021.06.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 06/02/2021] [Indexed: 12/24/2022] Open
Abstract
The genetic causes of global developmental delay (GDD) and intellectual disability (ID) are diverse and include variants in numerous ion channels and transporters. Loss-of-function variants in all five endosomal/lysosomal members of the CLC family of Cl- channels and Cl-/H+ exchangers lead to pathology in mice, humans, or both. We have identified nine variants in CLCN3, the gene encoding CIC-3, in 11 individuals with GDD/ID and neurodevelopmental disorders of varying severity. In addition to a homozygous frameshift variant in two siblings, we identified eight different heterozygous de novo missense variants. All have GDD/ID, mood or behavioral disorders, and dysmorphic features; 9/11 have structural brain abnormalities; and 6/11 have seizures. The homozygous variants are predicted to cause loss of ClC-3 function, resulting in severe neurological disease similar to the phenotype observed in Clcn3-/- mice. Their MRIs show possible neurodegeneration with thin corpora callosa and decreased white matter volumes. Individuals with heterozygous variants had a range of neurodevelopmental anomalies including agenesis of the corpus callosum, pons hypoplasia, and increased gyral folding. To characterize the altered function of the exchanger, electrophysiological analyses were performed in Xenopus oocytes and mammalian cells. Two variants, p.Ile607Thr and p.Thr570Ile, had increased currents at negative cytoplasmic voltages and loss of inhibition by luminal acidic pH. In contrast, two other variants showed no significant difference in the current properties. Overall, our work establishes a role for CLCN3 in human neurodevelopment and shows that both homozygous loss of ClC-3 and heterozygous variants can lead to GDD/ID and neuroanatomical abnormalities.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Pankaj B Agrawal
- Division of Newborn Medicine, Department of Pediatrics, Boston Children's Hospital, Boston, MA 02115, USA; The Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, MA 02115, USA; Division of Genetics & Genomics, Department of Pediatrics, Boston Children's Hospital, MA 02115, USA.
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30
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Boscia F, Elkjaer ML, Illes Z, Kukley M. Altered Expression of Ion Channels in White Matter Lesions of Progressive Multiple Sclerosis: What Do We Know About Their Function? Front Cell Neurosci 2021; 15:685703. [PMID: 34276310 PMCID: PMC8282214 DOI: 10.3389/fncel.2021.685703] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Accepted: 05/23/2021] [Indexed: 12/19/2022] Open
Abstract
Despite significant advances in our understanding of the pathophysiology of multiple sclerosis (MS), knowledge about contribution of individual ion channels to axonal impairment and remyelination failure in progressive MS remains incomplete. Ion channel families play a fundamental role in maintaining white matter (WM) integrity and in regulating WM activities in axons, interstitial neurons, glia, and vascular cells. Recently, transcriptomic studies have considerably increased insight into the gene expression changes that occur in diverse WM lesions and the gene expression fingerprint of specific WM cells associated with secondary progressive MS. Here, we review the ion channel genes encoding K+, Ca2+, Na+, and Cl- channels; ryanodine receptors; TRP channels; and others that are significantly and uniquely dysregulated in active, chronic active, inactive, remyelinating WM lesions, and normal-appearing WM of secondary progressive MS brain, based on recently published bulk and single-nuclei RNA-sequencing datasets. We discuss the current state of knowledge about the corresponding ion channels and their implication in the MS brain or in experimental models of MS. This comprehensive review suggests that the intense upregulation of voltage-gated Na+ channel genes in WM lesions with ongoing tissue damage may reflect the imbalance of Na+ homeostasis that is observed in progressive MS brain, while the upregulation of a large number of voltage-gated K+ channel genes may be linked to a protective response to limit neuronal excitability. In addition, the altered chloride homeostasis, revealed by the significant downregulation of voltage-gated Cl- channels in MS lesions, may contribute to an altered inhibitory neurotransmission and increased excitability.
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Affiliation(s)
- Francesca Boscia
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, University of Naples "Federico II", Naples, Italy
| | - Maria Louise Elkjaer
- Neurology Research Unit, Department of Clinical Research, University of Southern Denmark, Odense, Denmark.,Department of Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Zsolt Illes
- Neurology Research Unit, Department of Clinical Research, University of Southern Denmark, Odense, Denmark.,Department of Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark.,Department of Neurology, Odense University Hospital, Odense, Denmark
| | - Maria Kukley
- Achucarro Basque Center for Neuroscience, Leioa, Spain.,Ikerbasque Basque Foundation for Science, Bilbao, Spain
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31
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Difference of pain vulnerability in adult and juvenile rodents: the role of SIRT1-mediated ClC-3 trafficking in sensory neurons. Pain 2021; 162:1882-1896. [PMID: 33433144 DOI: 10.1097/j.pain.0000000000002176] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 12/15/2020] [Indexed: 12/16/2022]
Abstract
ABSTRACT Adults are more likely to suffer from chronic pain than minors, and its underlying mechanism remains unclear. SIRT1 an important age-related protein with function of lifespan extension; whether SIRT1 plays a role in the different pain vulnerability of adult and juvenile remains unclear. Here, we found that the expression level of SIRT1 in dorsal root ganglia (DRG) was related to the pain vulnerability. After nerve injury, the expression of SIRT1 in DRG was decreased in adult rodents whereas increased in juvenile rodents. Differential manipulation of SIRT1 abolished the different pain vulnerability between adult and juvenile rodents. Furthermore, SIRT1 interacted with ClC-3 channel and mediated ClC-3 membrane trafficking and Cl- current in DRG neurons. Differential manipulation of ClC-3 also abolished the difference in pain vulnerability between adult and juvenile rodents. The different anti-inflammatory ability determined the different change trends of SIRT1 and ClC-3 trafficking contributed to the different pain vulnerability in adult and juvenile rodents. In addition, the serum SIRT1 level was negatively correlated with the pain score in patients with chronic pain. These findings revealed the mechanism of the difference in pain vulnerability between adult and juvenile rodents and provided evidence for age-specific treatment of chronic pain.
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32
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He H, Guzman RE, Cao D, Sierra-Marquez J, Yin F, Fahlke C, Peng J, Stauber T. The molecular and phenotypic spectrum of CLCN4-related epilepsy. Epilepsia 2021; 62:1401-1415. [PMID: 33951195 DOI: 10.1111/epi.16906] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 04/01/2021] [Accepted: 04/01/2021] [Indexed: 01/02/2023]
Abstract
OBJECTIVE This study was undertaken to expand the phenotypic and genetic spectrum of CLCN4-related epilepsy and to investigate genotype-phenotype correlations. METHODS We systematically reviewed the phenotypic and genetic spectrum of newly diagnosed and previously reported patients with CLCN4-related epilepsy. Three novel variants identified in four patients reported in this study were evaluated through in silico prediction and functional analysis by Western blot, immunofluorescence, and electrophysiological measurements. RESULTS Epilepsy was diagnosed in 54.55% (24/44) of individuals with CLCN4-related disorders and was drug-resistant in most cases. Of 24 patients, 15 had epileptic encephalopathy and four died at an early age; 69.57% of patients had seizure onset within the first year of life. Myoclonic seizures are the most common seizure type, and 56.25% of patients presented multiple seizure types. Notably, seizure outcome was favorable in individuals with only one seizure type. All patients showed intellectual disability, which was severe in 65.22% of patients. Additional common features included language delay, behavioral disorders, and dysmorphic features. Five patients benefitted from treatment with lamotrigine. Most variants, which were mainly missense (79.17%), were inherited (70.83%). Whereas frameshift, intragenic deletion, or inherited variants were associated with milder phenotypes, missense or de novo variants led to more severe phenotypes. All evaluated CLCN4 variants resulted in loss of function with reduced ClC-4 currents. Nonetheless, genotype-phenotype relationships for CLCN4-related epilepsy are not straightforward, as phenotypic variability was observed in recurrent variants and within single families. SIGNIFICANCE Pathogenic CLCN4 variants contribute significantly to the genetic etiology of epilepsy. The phenotypic spectrum of CLCN4-related epilepsy includes drug-resistant seizures, cognitive and language impairment, behavioral disorders, and congenital anomalies. Notably, the mutation type and the number of seizure types correlate with the severity of the phenotype, suggesting its use for clinical prognosis. Lamotrigine can be considered a therapeutic option.
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Affiliation(s)
- Hailan He
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Raul E Guzman
- Institute of Biological Information Processing (IBI-1), Molecular and Cell Physiology, Jülich Research Center, Jülich, Germany
| | - Dezhi Cao
- Neurology Department, Shenzhen Children's Hospital, Shenzhen, China
| | - Juan Sierra-Marquez
- Institute of Biological Information Processing (IBI-1), Molecular and Cell Physiology, Jülich Research Center, Jülich, Germany
| | - Fei Yin
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Christoph Fahlke
- Institute of Biological Information Processing (IBI-1), Molecular and Cell Physiology, Jülich Research Center, Jülich, Germany
| | - Jing Peng
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Tobias Stauber
- Institute of Chemistry and Biochemistry, Berlin Free University, Berlin, Germany.,Department of Human Medicine and Institute for Molecular Medicine, MSH Medical School Hamburg, Hamburg, Germany
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33
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Courtland JL, Bradshaw TWA, Waitt G, Soderblom EJ, Ho T, Rajab A, Vancini R, Kim IH, Soderling SH. Genetic disruption of WASHC4 drives endo-lysosomal dysfunction and cognitive-movement impairments in mice and humans. eLife 2021; 10:e61590. [PMID: 33749590 PMCID: PMC7984842 DOI: 10.7554/elife.61590] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 02/09/2021] [Indexed: 12/12/2022] Open
Abstract
Mutation of the Wiskott-Aldrich syndrome protein and SCAR homology (WASH) complex subunit, SWIP, is implicated in human intellectual disability, but the cellular etiology of this association is unknown. We identify the neuronal WASH complex proteome, revealing a network of endosomal proteins. To uncover how dysfunction of endosomal SWIP leads to disease, we generate a mouse model of the human WASHC4c.3056C>G mutation. Quantitative spatial proteomics analysis of SWIPP1019R mouse brain reveals that this mutation destabilizes the WASH complex and uncovers significant perturbations in both endosomal and lysosomal pathways. Cellular and histological analyses confirm that SWIPP1019R results in endo-lysosomal disruption and uncover indicators of neurodegeneration. We find that SWIPP1019R not only impacts cognition, but also causes significant progressive motor deficits in mice. A retrospective analysis of SWIPP1019R patients reveals similar movement deficits in humans. Combined, these findings support the model that WASH complex destabilization, resulting from SWIPP1019R, drives cognitive and motor impairments via endo-lysosomal dysfunction in the brain.
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Affiliation(s)
- Jamie L Courtland
- Department of Neurobiology, Duke University School of MedicineDurhamUnited States
| | - Tyler WA Bradshaw
- Department of Neurobiology, Duke University School of MedicineDurhamUnited States
| | - Greg Waitt
- Proteomics and Metabolomics Shared Resource, Duke University School of MedicineDurhamUnited States
| | - Erik J Soderblom
- Proteomics and Metabolomics Shared Resource, Duke University School of MedicineDurhamUnited States
- Department of Cell Biology, Duke University School of MedicineDurhamUnited States
| | - Tricia Ho
- Proteomics and Metabolomics Shared Resource, Duke University School of MedicineDurhamUnited States
| | - Anna Rajab
- Burjeel Hospital, VPS HealthcareMuscatOman
| | - Ricardo Vancini
- Department of Pathology, Duke University School of MedicineDurhamUnited States
| | - Il Hwan Kim
- Department of Cell Biology, Duke University School of MedicineDurhamUnited States
- Department of Anatomy and Neurobiology, University of Tennessee Heath Science CenterMemphisUnited States
| | - Scott H Soderling
- Department of Neurobiology, Duke University School of MedicineDurhamUnited States
- Department of Cell Biology, Duke University School of MedicineDurhamUnited States
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34
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Exploring dementia and neuronal ceroid lipofuscinosis genes in 100 FTD-like patients from 6 towns and rural villages on the Adriatic Sea cost of Apulia. Sci Rep 2021; 11:6353. [PMID: 33737586 PMCID: PMC7973810 DOI: 10.1038/s41598-021-85494-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Accepted: 03/01/2021] [Indexed: 12/30/2022] Open
Abstract
Frontotemporal dementia (FTD) refers to a complex spectrum of clinically and genetically heterogeneous disorders. Although fully penetrant mutations in several genes have been identified and can explain the pathogenic mechanisms underlying a great portion of the Mendelian forms of the disease, still a significant number of families and sporadic cases remains genetically unsolved. We performed whole exome sequencing in 100 patients with a late-onset and heterogeneous FTD-like clinical phenotype from Apulia and screened mendelian dementia and neuronal ceroid lipofuscinosis genes. We identified a nonsense mutation in SORL1 VPS domain (p.R744X), in 2 siblings displaying AD with severe language problems and primary progressive aphasia and a near splice-site mutation in CLCN6 (p.S116P) segregating with an heterogeneous phenotype, ranging from behavioural FTD to FTD with memory onset and to the logopenic variant of primary progressive aphasia in one family. Moreover 2 sporadic cases with behavioural FTD carried heterozygous mutations in the CSF1R Tyrosin kinase flanking regions (p.E573K and p.R549H). By contrast, only a minority of patients carried pathogenic C9orf72 repeat expansions (1%) and likely moderately pathogenic variants in GRN (p.C105Y, p.C389fs and p.C139R) (3%). In concert with recent studies, our findings support a common pathogenic mechanisms between FTD and neuronal ceroid lipofuscinosis and suggests that neuronal ceroid lipofuscinosis genes should be investigated also in dementia patients with predominant frontal symptoms and language impairments.
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35
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Lin CH, Tsai PI, Lin HY, Hattori N, Funayama M, Jeon B, Sato K, Abe K, Mukai Y, Takahashi Y, Li Y, Nishioka K, Yoshino H, Daida K, Chen ML, Cheng J, Huang CY, Tzeng SR, Wu YS, Lai HJ, Tsai HH, Yen RF, Lee NC, Lo WC, Hung YC, Chan CC, Ke YC, Chao CC, Hsieh ST, Farrer M, Wu RM. Mitochondrial UQCRC1 mutations cause autosomal dominant parkinsonism with polyneuropathy. Brain 2021; 143:3352-3373. [PMID: 33141179 PMCID: PMC7719032 DOI: 10.1093/brain/awaa279] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 06/25/2020] [Accepted: 07/12/2020] [Indexed: 12/14/2022] Open
Abstract
Parkinson's disease is a neurodegenerative disorder with a multifactorial aetiology. Nevertheless, the genetic predisposition in many families with multi-incidence disease remains unknown. This study aimed to identify novel genes that cause familial Parkinson's disease. Whole exome sequencing was performed in three affected members of the index family with a late-onset autosomal-dominant parkinsonism and polyneuropathy. We identified a novel heterozygous substitution c.941A>C (p.Tyr314Ser) in the mitochondrial ubiquinol-cytochrome c reductase core protein 1 (UQCRC1) gene, which co-segregates with disease within the family. Additional analysis of 699 unrelated Parkinson's disease probands with autosomal-dominant Parkinson's disease and 1934 patients with sporadic Parkinson's disease revealed another two variants in UQCRC1 in the probands with familial Parkinson's disease, c.931A>C (p.Ile311Leu) and an allele with concomitant splicing mutation (c.70-1G>A) and a frameshift insertion (c.73_74insG, p.Ala25Glyfs*27). All substitutions were absent in 1077 controls and the Taiwan Biobank exome database from healthy participants (n = 1517 exomes). We then assayed the pathogenicity of the identified rare variants using CRISPR/Cas9-based knock-in human dopaminergic SH-SY5Y cell lines, Drosophila and mouse models. Mutant UQCRC1 expression leads to neurite degeneration and mitochondrial respiratory chain dysfunction in SH-SY5Y cells. UQCRC1 p.Tyr314Ser knock-in Drosophila and mouse models exhibit age-dependent locomotor defects, dopaminergic neuronal loss, peripheral neuropathy, impaired respiratory chain complex III activity and aberrant mitochondrial ultrastructures in nigral neurons. Furthermore, intraperitoneal injection of levodopa could significantly improve the motor dysfunction in UQCRC1 p.Tyr314Ser mutant knock-in mice. Taken together, our in vitro and in vivo studies support the functional pathogenicity of rare UQCRC1 variants in familial parkinsonism. Our findings expand an additional link of mitochondrial complex III dysfunction in Parkinson's disease.
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Affiliation(s)
- Chin-Hsien Lin
- Department of Neurology, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Pei-I Tsai
- Department of Biochemistry and Biophysics, University of California San Francisco, USA
| | - Han-Yi Lin
- Department of Neurology, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Nobutaka Hattori
- Department of Neurology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Manabu Funayama
- Research Institute for Diseases of Old Age, Graduate School of Medicine, Juntendo University, Tokyo, Japan
| | - Beomseok Jeon
- Department of Neurology, Movement Disorder Center, Seoul National University Hospital, Parkinson Study Group, Seoul National University College of Medicine, Seoul, Korea
| | - Kota Sato
- Department of Neurology, Okayama University Medical School, Okayama, Japan
| | - Koji Abe
- Department of Neurology, Okayama University Medical School, Okayama, Japan
| | - Yohei Mukai
- Department of Neurology, National Center Hospital, National Center of Neurology and Psychiatry (NCNP), Tokyo, Japan
| | - Yuji Takahashi
- Department of Neurology, National Center Hospital, National Center of Neurology and Psychiatry (NCNP), Tokyo, Japan
| | - Yuanzhe Li
- Department of Neurology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Kenya Nishioka
- Department of Neurology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Hiroyo Yoshino
- Research Institute for Diseases of Old Age, Graduate School of Medicine, Juntendo University, Tokyo, Japan
| | - Kensuke Daida
- Department of Neurology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Meng-Ling Chen
- Department of Neurology, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Jay Cheng
- Department of Neurology, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Cheng-Yen Huang
- The first core laboratory, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Shiou-Ru Tzeng
- Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Yen-Sheng Wu
- Electron Microscope Laboratory of Tzong Jwo Jang, College of Medicine, Fu Jen Catholic University, Taipei, Taiwan
| | - Hsing-Jung Lai
- Department of Neurology, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Hsin-Hsi Tsai
- Department of Neurology, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Ruoh-Fang Yen
- Department of Nuclear Medicine, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Ni-Chung Lee
- Department of Medical Genetics, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Wen-Chun Lo
- Graduate Institute of Physiology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Yu-Chien Hung
- Graduate Institute of Physiology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Chih-Chiang Chan
- Graduate Institute of Physiology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Yi-Ci Ke
- Department of Neurology, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Chi-Chao Chao
- Department of Neurology, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Sung-Tsang Hsieh
- Department of Neurology, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan.,Department of Anatomy and Cell Biology, National Taiwan University College of Medicine, Taipei, Taiwan.,Graduate Institute of Brain and Mind Sciences, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Matthew Farrer
- Department of Neurology, McKnight Brain Institute, University of Florida, Gainesville, FL, USA.,Center for Applied Neurogenetics, University of British Columbia, Canada
| | - Ruey-Meei Wu
- Department of Neurology, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan
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36
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Chebotarev AS, Pochechuev MS, Lanin AA, Kelmanson IV, Kotova DA, Fetisova ES, Panova AS, Bilan DS, Fedotov AB, Belousov VV, Zheltikov AM. Enhanced-contrast two-photon optogenetic pH sensing and pH-resolved brain imaging. JOURNAL OF BIOPHOTONICS 2021; 14:e202000301. [PMID: 33205577 DOI: 10.1002/jbio.202000301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 10/29/2020] [Accepted: 11/16/2020] [Indexed: 06/11/2023]
Abstract
We present experiments on cell cultures and brain slices that demonstrate two-photon optogenetic pH sensing and pH-resolved brain imaging using a laser driver whose spectrum is carefully tailored to provide the maximum contrast of a ratiometric two-photon fluorescence readout from a high-brightness genetically encoded yellow-fluorescent-protein-based sensor, SypHer3s. Two spectrally isolated components of this laser field are set to induce two-photon-excited fluorescence (2PEF) by driving SypHer3s through one of two excitation pathways-via either the protonated or deprotonated states of its chromophore. With the spectrum of the laser field accurately adjusted for a maximum contrast of these two 2PEF signals, the ratio of their intensities is shown to provide a remarkably broad dynamic range for pH measurements, enabling high-contrast optogenetic deep-brain pH sensing and pH-resolved 2PEF imaging within a vast class of biological systems, ranging from cell cultures to the living brain.
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Affiliation(s)
- Artem S Chebotarev
- Physics Department, International Laser Center, M.V. Lomonosov Moscow State University, Moscow, Russia
| | - Matvei S Pochechuev
- Physics Department, International Laser Center, M.V. Lomonosov Moscow State University, Moscow, Russia
| | - Aleksandr A Lanin
- Physics Department, International Laser Center, M.V. Lomonosov Moscow State University, Moscow, Russia
- Russian Quantum Center, Moscow, Russia
- Kazan Quantum Center, A.N. Tupolev Kazan National Research Technical University, Kazan, Russia
| | - Ilya V Kelmanson
- M.M. Shemyakin and Yu.A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
- Pirogov Russian National Research Medical University, Moscow, Russia
| | - Daria A Kotova
- M.M. Shemyakin and Yu.A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Elena S Fetisova
- M.M. Shemyakin and Yu.A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Anastasiya S Panova
- M.M. Shemyakin and Yu.A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Dmitry S Bilan
- M.M. Shemyakin and Yu.A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
- Pirogov Russian National Research Medical University, Moscow, Russia
| | - Andrei B Fedotov
- Physics Department, International Laser Center, M.V. Lomonosov Moscow State University, Moscow, Russia
- Russian Quantum Center, Moscow, Russia
- Kazan Quantum Center, A.N. Tupolev Kazan National Research Technical University, Kazan, Russia
- National University of Science and Technology "MISiS,", Moscow, Russia
| | - Vsevolod V Belousov
- M.M. Shemyakin and Yu.A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
- Pirogov Russian National Research Medical University, Moscow, Russia
- Federal Center of Brain Research and Neurotechnologies of the Federal Medical Biological Agency, Moscow, Russia
| | - Aleksei M Zheltikov
- Physics Department, International Laser Center, M.V. Lomonosov Moscow State University, Moscow, Russia
- Russian Quantum Center, Moscow, Russia
- Kazan Quantum Center, A.N. Tupolev Kazan National Research Technical University, Kazan, Russia
- Department of Physics and Astronomy, Texas A&M University, College Station, Texas, USA
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37
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Bose S, He H, Stauber T. Neurodegeneration Upon Dysfunction of Endosomal/Lysosomal CLC Chloride Transporters. Front Cell Dev Biol 2021; 9:639231. [PMID: 33708769 PMCID: PMC7940362 DOI: 10.3389/fcell.2021.639231] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 02/03/2021] [Indexed: 12/15/2022] Open
Abstract
The regulation of luminal ion concentrations is critical for the function of, and transport between intracellular organelles. The importance of the acidic pH in the compartments of the endosomal-lysosomal pathway has been well-known for decades. Besides the V-ATPase, which pumps protons into their lumen, a variety of ion transporters and channels is involved in the regulation of the organelles' complex ion homeostasis. Amongst these are the intracellular members of the CLC family, ClC-3 through ClC-7. They localize to distinct but overlapping compartments of the endosomal-lysosomal pathway, partially with tissue-specific expression. Functioning as 2Cl−/H+ exchangers, they can support the vesicular acidification and accumulate luminal Cl−. Mutations in the encoding genes in patients and mouse models underlie severe phenotypes including kidney stones with CLCN5 and osteopetrosis or hypopigmentation with CLCN7. Dysfunction of those intracellular CLCs that are expressed in neurons lead to neuronal defects. Loss of endosomal ClC-3, which heteromerizes with ClC-4, results in neurodegeneration. Mutations in ClC-4 are associated with epileptic encephalopathy and intellectual disability. Mice lacking the late endosomal ClC-6 develop a lysosomal storage disease with reduced pain sensitivity. Human gene variants have been associated with epilepsy, and a gain-of-function mutation causes early-onset neurodegeneration. Dysfunction of the lysosomal ClC-7 leads to a lysosomal storage disease and neurodegeneration in mice and humans. Reduced luminal chloride, as well as altered calcium regulation, has been associated with lysosomal storage diseases in general. This review discusses the properties of endosomal and lysosomal Cl−/H+ exchange by CLCs and how various alterations of ion transport by CLCs impact organellar ion homeostasis and function in neurodegenerative disorders.
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Affiliation(s)
- Shroddha Bose
- Institute for Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
| | - Hailan He
- Institute for Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany.,Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Tobias Stauber
- Institute for Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany.,Department of Human Medicine and Institute for Molecular Medicine, MSH Medical School Hamburg, Hamburg, Germany
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38
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He H, Cao X, Yin F, Wu T, Stauber T, Peng J. West Syndrome Caused By a Chloride/Proton Exchange-Uncoupling CLCN6 Mutation Related to Autophagic-Lysosomal Dysfunction. Mol Neurobiol 2021; 58:2990-2999. [PMID: 33590434 DOI: 10.1007/s12035-021-02291-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 01/12/2021] [Indexed: 12/25/2022]
Abstract
Vesicular chloride/proton exchangers of the CLC family are critically involved in the function of the endosomal-lysosomal pathway. Their dysfunction leads to severe disorders including intellectual disability and epilepsy for ClC-4, Dent's disease for ClC-5, and lysosomal storage disease and osteopetrosis for ClC-7. Here, we report a de novo variant p.Glu200Ala (p.E200A; c.599A>C) of the late endosomal ClC-6, encoded by CLCN6, in a patient with West syndrome (WS), severe developmental delay, autism, movement disorder, microcephaly, facial dysmorphism, and visual impairment. Mutation of this conserved glutamate uncouples chloride transport from proton antiport by ClC-6. This affects organellar ion homeostasis and was shown to be deleterious for other CLCs. In this study, we found that upon heterologous expression, the ClC-6 E200A variant caused autophagosome accumulation and impaired the clearance of autophagosomes by blocking autophagosome-lysosome fusion. Our study provides clinical and functional support for an association between CLCN6 variants and WS. Our findings also provide novel insights into the molecular mechanisms underlying the pathogenesis of WS, suggesting an involvement of autophagic-lysosomal dysfunction.
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Affiliation(s)
- Hailan He
- Department of Pediatrics, Xiangya Hospital, Central South University, Xiangya Road 87, Changsha, 410008, Hunan, China
| | - Xiaoshuang Cao
- Department of Pediatrics, Xiangya Hospital, Central South University, Xiangya Road 87, Changsha, 410008, Hunan, China
| | - Fei Yin
- Department of Pediatrics, Xiangya Hospital, Central South University, Xiangya Road 87, Changsha, 410008, Hunan, China.,Hunan Intellectual and Developmental Disabilities Research Center, Xiangya Road 87, Changsha, 410008, Hunan, China
| | - Tenghui Wu
- Department of Pediatrics, Xiangya Hospital, Central South University, Xiangya Road 87, Changsha, 410008, Hunan, China
| | - Tobias Stauber
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Thielallee 63, 14195, Berlin, Germany.,Institute for Molecular Medicine and Department of Human Medicine, MSH Medical School Hamburg, Am Kaiserkai 1, 20457, Hamburg, Germany
| | - Jing Peng
- Department of Pediatrics, Xiangya Hospital, Central South University, Xiangya Road 87, Changsha, 410008, Hunan, China. .,Hunan Intellectual and Developmental Disabilities Research Center, Xiangya Road 87, Changsha, 410008, Hunan, China.
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39
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Reduced Graphene Oxides Modulate the Expression of Cell Receptors and Voltage-Dependent Ion Channel Genes of Glioblastoma Multiforme. Int J Mol Sci 2021; 22:ijms22020515. [PMID: 33419226 PMCID: PMC7825604 DOI: 10.3390/ijms22020515] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 12/29/2020] [Accepted: 01/04/2021] [Indexed: 02/07/2023] Open
Abstract
The development of nanotechnology based on graphene and its derivatives has aroused great scientific interest because of their unusual properties. Graphene (GN) and its derivatives, such as reduced graphene oxide (rGO), exhibit antitumor effects on glioblastoma multiforme (GBM) cells in vitro. The antitumor activity of rGO with different contents of oxygen-containing functional groups and GN was compared. Using FTIR (fourier transform infrared) analysis, the content of individual functional groups (GN/exfoliation (ExF), rGO/thermal (Term), rGO/ammonium thiosulphate (ATS), and rGO/ thiourea dioxide (TUD)) was determined. Cell membrane damage, as well as changes in the cell membrane potential, was analyzed. Additionally, the gene expression of voltage-dependent ion channels (clcn3, clcn6, cacna1b, cacna1d, nalcn, kcne4, kcnj10, and kcnb1) and extracellular receptors was determined. A reduction in the potential of the U87 glioma cell membrane was observed after treatment with rGO/ATS and rGO/TUD flakes. Moreover, it was also demonstrated that major changes in the expression of voltage-dependent ion channel genes were observed in clcn3, nalcn, and kcne4 after treatment with rGO/ATS and rGO/TUD flakes. Furthermore, the GN/ExF, rGO/ATS, and rGO/TUD flakes significantly reduced the expression of extracellular receptors (uPar, CD105) in U87 glioblastoma cells. In conclusion, the cytotoxic mechanism of rGO flakes may depend on the presence and types of oxygen-containing functional groups, which are more abundant in rGO compared to GN.
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40
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Klemens CA, Chulkov EG, Wu J, Hye Khan MA, Levchenko V, Flister MJ, Imig JD, Kriegel AJ, Palygin O, Staruschenko A. Loss of Chloride Channel 6 (CLC-6) Affects Vascular Smooth Muscle Contractility and Arterial Stiffness via Alterations to Golgi Calcium Stores. Hypertension 2021; 77:582-593. [PMID: 33390052 DOI: 10.1161/hypertensionaha.120.16589] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Genome-wide association studies have found a number of potential genes involved in blood pressure regulation; however, the functional role of many of these candidates has yet to be established. One such candidate gene is CLCN6, which encodes the transmembrane protein, chloride channel 6 (ClC-6). Although the CLCN6 locus has been widely associated with human blood pressure regulation, the mechanistic role of ClC-6 in blood pressure homeostasis at the molecular, cellular, and physiological levels is completely unknown. In this study, we demonstrate that rats with a functional knockout of ClC-6 on the Dahl Salt-Sensitive rat background (SS-Clcn6) have lower diastolic but not systolic blood pressures. The effect of diastolic blood pressure attenuation was independent of dietary salt exposure in knockout animals. Moreover, SS-Clcn6 rats are protected from hypertension-induced cardiac hypertrophy and arterial stiffening; however, they have impaired vasodilation and dysregulated intracellular calcium handling. ClC-6 is highly expressed in vascular smooth muscle cells where it is targeted to the Golgi apparatus. Using bilayer electrophysiology, we provide evidence that recombinant human ClC-6 protein can function as a channel. Last, we demonstrate that loss of ClC-6 function reduces Golgi calcium stores, which may play a previously unidentified role in vascular contraction and relaxation signaling in vascular smooth muscle cells. Collectively, these data indicate that ClC-6 may modulate blood pressure by regulating Golgi calcium reserves, which in turn contribute to vascular smooth muscle function.
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Affiliation(s)
- Christine A Klemens
- From the Department of Physiology (C.A.K., E.G.C., J.W., V.L., M.J.F., A.J.K., O.P., A.S.), Medical College of Wisconsin.,Cardiovascular Center (C.A.K., J.W., J.D.I., O.P., A.S.), Medical College of Wisconsin
| | - Evgeny G Chulkov
- From the Department of Physiology (C.A.K., E.G.C., J.W., V.L., M.J.F., A.J.K., O.P., A.S.), Medical College of Wisconsin.,Department of Cell Biology, Neurobiology and Anatomy (E.G.C.), Medical College of Wisconsin
| | - Jing Wu
- From the Department of Physiology (C.A.K., E.G.C., J.W., V.L., M.J.F., A.J.K., O.P., A.S.), Medical College of Wisconsin.,Cardiovascular Center (C.A.K., J.W., J.D.I., O.P., A.S.), Medical College of Wisconsin
| | - Md Abdul Hye Khan
- Department of Pharmacology (M.A.H.K., J.D.I.), Medical College of Wisconsin
| | - Vladislav Levchenko
- From the Department of Physiology (C.A.K., E.G.C., J.W., V.L., M.J.F., A.J.K., O.P., A.S.), Medical College of Wisconsin
| | - Michael J Flister
- From the Department of Physiology (C.A.K., E.G.C., J.W., V.L., M.J.F., A.J.K., O.P., A.S.), Medical College of Wisconsin
| | - John D Imig
- Department of Pharmacology (M.A.H.K., J.D.I.), Medical College of Wisconsin.,Cardiovascular Center (C.A.K., J.W., J.D.I., O.P., A.S.), Medical College of Wisconsin
| | - Alison J Kriegel
- From the Department of Physiology (C.A.K., E.G.C., J.W., V.L., M.J.F., A.J.K., O.P., A.S.), Medical College of Wisconsin
| | - Oleg Palygin
- From the Department of Physiology (C.A.K., E.G.C., J.W., V.L., M.J.F., A.J.K., O.P., A.S.), Medical College of Wisconsin.,Cardiovascular Center (C.A.K., J.W., J.D.I., O.P., A.S.), Medical College of Wisconsin
| | - Alexander Staruschenko
- From the Department of Physiology (C.A.K., E.G.C., J.W., V.L., M.J.F., A.J.K., O.P., A.S.), Medical College of Wisconsin.,Cardiovascular Center (C.A.K., J.W., J.D.I., O.P., A.S.), Medical College of Wisconsin.,Clement J. Zablocki VA Medical Center, Milwaukee (A.S.)
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41
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Kwon HC, Yu Y, Fairclough RH, Chen TY. Proton-dependent inhibition, inverted voltage activation, and slow gating of CLC-0 Chloride Channel. PLoS One 2020; 15:e0240704. [PMID: 33362212 PMCID: PMC7757909 DOI: 10.1371/journal.pone.0240704] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Accepted: 12/03/2020] [Indexed: 11/21/2022] Open
Abstract
CLC-0, a prototype Cl- channel in the CLC family, employs two gating mechanisms that control its ion-permeation pore: fast gating and slow gating. The negatively-charged sidechain of a pore glutamate residue, E166, is known to be the fast gate, and the swinging of this sidechain opens or closes the pore of CLC-0 on the millisecond time scale. The other gating mechanism, slow gating, operates with much slower kinetics in the range of seconds to tens or even hundreds of seconds, and it is thought to involve still-unknown conformational rearrangements. Here, we find that low intracellular pH (pHi) facilitates the closure of the CLC-0’s slow gate, thus generating current inhibition. The rate of low pHi-induced current inhibition increases with intracellular H+ concentration ([H+]i)—the time constants of current inhibition by low pHi = 4.5, 5.5 and 6 are roughly 0.1, 1 and 10 sec, respectively, at room temperature. In comparison, the time constant of the slow gate closure at pHi = 7.4 at room temperature is hundreds of seconds. The inhibition by low pHi is significantly less prominent in mutants favoring the slow-gate open state (such as C212S and Y512A), further supporting the fact that intracellular H+ enhances the slow-gate closure in CLC-0. A fast inhibition by low pHi causes an apparent inverted voltage-dependent activation in the wild-type CLC-0, a behavior similar to those in some channel mutants such as V490W in which only membrane hyperpolarization can open the channel. Interestingly, when V490W mutation is constructed in the background of C212S or Y512A mutation, the inverted voltage-dependent activation disappears. We propose that the slow kinetics of CLC-0’s slow-gate closure may be due to low [H+]i rather than due to the proposed large conformational change of the channel protein. Our results also suggest that the inverted voltage-dependent opening observed in some mutant channels may result from fast closure of the slow gate by the mutations.
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Affiliation(s)
- Hwoi Chan Kwon
- Biophysics Graduate Program, University of California, Davis, California, United States of America
| | - Yawei Yu
- BMCDB Graduate Program, University of California, Davis, California, United States of America
| | - Robert H. Fairclough
- Biophysics Graduate Program, University of California, Davis, California, United States of America
- BMCDB Graduate Program, University of California, Davis, California, United States of America
- Center for Neuroscience, University of California, Davis, California, United States of America
| | - Tsung-Yu Chen
- Biophysics Graduate Program, University of California, Davis, California, United States of America
- BMCDB Graduate Program, University of California, Davis, California, United States of America
- Department of Neurology, University of California, Davis, California, United States of America
- Center for Neuroscience, University of California, Davis, California, United States of America
- * E-mail:
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42
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Polovitskaya MM, Barbini C, Martinelli D, Harms FL, Cole FS, Calligari P, Bocchinfuso G, Stella L, Ciolfi A, Niceta M, Rizza T, Shinawi M, Sisco K, Johannsen J, Denecke J, Carrozzo R, Wegner DJ, Kutsche K, Tartaglia M, Jentsch TJ. A Recurrent Gain-of-Function Mutation in CLCN6, Encoding the ClC-6 Cl -/H +-Exchanger, Causes Early-Onset Neurodegeneration. Am J Hum Genet 2020; 107:1062-1077. [PMID: 33217309 PMCID: PMC7820737 DOI: 10.1016/j.ajhg.2020.11.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Accepted: 11/02/2020] [Indexed: 12/16/2022] Open
Abstract
Dysfunction of the endolysosomal system is often associated with neurodegenerative disease because postmitotic neurons are particularly reliant on the elimination of intracellular aggregates. Adequate function of endosomes and lysosomes requires finely tuned luminal ion homeostasis and transmembrane ion fluxes. Endolysosomal CLC Cl-/H+ exchangers function as electric shunts for proton pumping and in luminal Cl- accumulation. We now report three unrelated children with severe neurodegenerative disease, who carry the same de novo c.1658A>G (p.Tyr553Cys) mutation in CLCN6, encoding the late endosomal Cl-/H+-exchanger ClC-6. Whereas Clcn6-/- mice have only mild neuronal lysosomal storage abnormalities, the affected individuals displayed severe developmental delay with pronounced generalized hypotonia, respiratory insufficiency, and variable neurodegeneration and diffusion restriction in cerebral peduncles, midbrain, and/or brainstem in MRI scans. The p.Tyr553Cys amino acid substitution strongly slowed ClC-6 gating and increased current amplitudes, particularly at the acidic pH of late endosomes. Transfection of ClC-6Tyr553Cys, but not ClC-6WT, generated giant LAMP1-positive vacuoles that were poorly acidified. Their generation strictly required ClC-6 ion transport, as shown by transport-deficient double mutants, and depended on Cl-/H+ exchange, as revealed by combination with the uncoupling p.Glu200Ala substitution. Transfection of either ClC-6Tyr553Cys/Glu200Ala or ClC-6Glu200Ala generated slightly enlarged vesicles, suggesting that p.Glu200Ala, previously associated with infantile spasms and microcephaly, is also pathogenic. Bafilomycin treatment abrogated vacuole generation, indicating that H+-driven Cl- accumulation osmotically drives vesicle enlargement. Our work establishes mutations in CLCN6 associated with neurological diseases, whose spectrum of clinical features depends on the differential impact of the allele on ClC-6 function.
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Affiliation(s)
- Maya M Polovitskaya
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), 13125 Berlin, Germany; Max-Delbrück-Centrum für Molekulare Medizin (MDC), 13125 Berlin, Germany
| | - Carlo Barbini
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), 13125 Berlin, Germany; Max-Delbrück-Centrum für Molekulare Medizin (MDC), 13125 Berlin, Germany
| | - Diego Martinelli
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, IRCCS, 00146 Rome, Italy
| | - Frederike L Harms
- Institute for Human Genetics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - F Sessions Cole
- Division of Newborn Medicine, Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, and St. Louis Children's Hospital, St. Louis, MO 63110, USA
| | - Paolo Calligari
- Department of Chemical Science and Technologies, University "Tor Vergata," 00133 Rome, Italy
| | - Gianfranco Bocchinfuso
- Department of Chemical Science and Technologies, University "Tor Vergata," 00133 Rome, Italy
| | - Lorenzo Stella
- Department of Chemical Science and Technologies, University "Tor Vergata," 00133 Rome, Italy
| | - Andrea Ciolfi
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, IRCCS, 00146 Rome, Italy
| | - Marcello Niceta
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, IRCCS, 00146 Rome, Italy
| | - Teresa Rizza
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, IRCCS, 00146 Rome, Italy
| | - Marwan Shinawi
- Division of Genetics and Genomic Medicine, Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, and St. Louis Children's Hospital, St. Louis, MO 63110, USA
| | - Kathleen Sisco
- Division of Genetics and Genomic Medicine, Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, and St. Louis Children's Hospital, St. Louis, MO 63110, USA
| | - Jessika Johannsen
- Children's Hospital, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Jonas Denecke
- Children's Hospital, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Rosalba Carrozzo
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, IRCCS, 00146 Rome, Italy
| | - Daniel J Wegner
- Division of Newborn Medicine, Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, and St. Louis Children's Hospital, St. Louis, MO 63110, USA
| | - Kerstin Kutsche
- Institute for Human Genetics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Marco Tartaglia
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, IRCCS, 00146 Rome, Italy.
| | - Thomas J Jentsch
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), 13125 Berlin, Germany; Max-Delbrück-Centrum für Molekulare Medizin (MDC), 13125 Berlin, Germany; NeuroCure Cluster of Excellence, Charité Universitätsmedizin, 10117 Berlin, Germany.
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43
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Watkins LC, DeGrado WF, Voth GA. Influenza A M2 Inhibitor Binding Understood through Mechanisms of Excess Proton Stabilization and Channel Dynamics. J Am Chem Soc 2020; 142:17425-17433. [PMID: 32933245 PMCID: PMC7564090 DOI: 10.1021/jacs.0c06419] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
![]()
Prevalent resistance to inhibitors
that target the influenza A
M2 proton channel has necessitated a continued drug design effort,
supported by a sustained study of the mechanism of channel function
and inhibition. Recent high-resolution X-ray crystal structures present
the first opportunity to see how the adamantyl amine class of inhibitors
bind to M2 and disrupt and interact with the channel’s water
network, providing insight into the critical properties that enable
their effective inhibition in wild-type M2. In this work, we examine
the hypothesis that these drugs act primarily as mechanism-based inhibitors
by comparing hydrated excess proton stabilization during proton transport
in M2 with the interactions revealed in the crystal structures, using
the Multiscale Reactive Molecular Dynamics (MS-RMD) methodology. MS-RMD,
unlike classical molecular dynamics, models the hydrated proton (hydronium-like
cation) as a dynamic excess charge defect and allows bonds to break
and form, capturing the intricate interactions between the hydrated
excess proton, protein atoms, and water. Through this, we show that
the ammonium group of the inhibitors is effectively positioned to
take advantage of the channel’s natural ability to stabilize
an excess protonic charge and act as a hydronium mimic. Additionally,
we show that the channel is especially stable in the drug binding
region, highlighting the importance of this property for binding the
adamantane group. Finally, we characterize an additional hinge point
near Val27, which dynamically responds to charge and inhibitor binding.
Altogether, this work further illuminates a dynamic understanding
of the mechanism of drug inhibition in M2, grounded in the fundamental
properties that enable the channel to transport and stabilize excess
protons, with critical implications for future drug design efforts.
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Affiliation(s)
- Laura C Watkins
- Department of Chemistry, Chicago Center for Theoretical Chemistry, Institute for Biophysical Dynamics and James Franck Institute, The University of Chicago, Chicago, Illinois 60637, United States
| | - William F DeGrado
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California 94158, United States
| | - Gregory A Voth
- Department of Chemistry, Chicago Center for Theoretical Chemistry, Institute for Biophysical Dynamics and James Franck Institute, The University of Chicago, Chicago, Illinois 60637, United States
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44
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Abstract
A limited number of peripheral targets generate pain. Inflammatory mediators can sensitize these. The review addresses targets acting exclusively or predominantly on sensory neurons, mediators involved in inflammation targeting sensory neurons, and mediators involved in a more general inflammatory process, of which an analgesic effect secondary to an anti-inflammatory effect can be expected. Different approaches to address these systems are discussed, including scavenging proinflammatory mediators, applying anti-inflammatory mediators, and inhibiting proinflammatory or facilitating anti-inflammatory receptors. New approaches are contrasted to established ones; the current stage of progress is mentioned, in particular considering whether there is data from a molecular and cellular level, from animals, or from human trials, including an early stage after a market release. An overview of publication activity is presented, considering a IuPhar/BPS-curated list of targets with restriction to pain-related publications, which was also used to identify topics.
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Affiliation(s)
- Cosmin I Ciotu
- Center of Physiology and Pharmacology, Medical University of Vienna, Schwarzspanierstrasse 17, 1090, Vienna, Austria
| | - Michael J M Fischer
- Center of Physiology and Pharmacology, Medical University of Vienna, Schwarzspanierstrasse 17, 1090, Vienna, Austria.
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45
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Skitchenko RK, Usoltsev D, Uspenskaya M, Kajava AV, Guskov A. Census of halide-binding sites in protein structures. Bioinformatics 2020; 36:3064-3071. [PMID: 32022861 PMCID: PMC7214031 DOI: 10.1093/bioinformatics/btaa079] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 01/24/2020] [Accepted: 01/29/2020] [Indexed: 12/02/2022] Open
Abstract
Motivation Halides are negatively charged ions of halogens, forming fluorides (F−), chlorides (Cl−), bromides (Br−) and iodides (I−). These anions are quite reactive and interact both specifically and non-specifically with proteins. Despite their ubiquitous presence and important roles in protein function, little is known about the preferences of halides binding to proteins. To address this problem, we performed the analysis of halide–protein interactions, based on the entries in the Protein Data Bank. Results We have compiled a pipeline for the quick analysis of halide-binding sites in proteins using the available software. Our analysis revealed that all of halides are strongly attracted by the guanidinium moiety of arginine side chains, however, there are also certain preferences among halides for other partners. Furthermore, there is a certain preference for coordination numbers in the binding sites, with a correlation between coordination numbers and amino acid composition. This pipeline can be used as a tool for the analysis of specific halide–protein interactions and assist phasing experiments relying on halides as anomalous scatters. Availability and implementation All data described in this article can be reproduced via complied pipeline published at https://github.com/rostkick/Halide_sites/blob/master/README.md. Supplementary information Supplementary data are available at Bioinformatics online.
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Affiliation(s)
| | - Dmitrii Usoltsev
- Institute BioEngineering, ITMO University, Saint-Petersburg 197101, Russia
| | - Mayya Uspenskaya
- Institute BioEngineering, ITMO University, Saint-Petersburg 197101, Russia
| | - Andrey V Kajava
- Institute BioEngineering, ITMO University, Saint-Petersburg 197101, Russia.,Centre de Recherche en Biologie cellulaire de Montpellier (CRBM), UMR 5237 CNRS, Universite Montpellier, Montpellier 34293, France
| | - Albert Guskov
- Groningen Biomolecular Sciences & Biotechnology Institute, University of Groningen, Groningen 9747 AG, the Netherlands
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46
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Wilke BU, Kummer KK, Leitner MG, Kress M. Chloride - The Underrated Ion in Nociceptors. Front Neurosci 2020; 14:287. [PMID: 32322187 PMCID: PMC7158864 DOI: 10.3389/fnins.2020.00287] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2019] [Accepted: 03/12/2020] [Indexed: 01/06/2023] Open
Abstract
In contrast to pain processing neurons in the spinal cord, where the importance of chloride conductances is already well established, chloride homeostasis in primary afferent neurons has received less attention. Sensory neurons maintain high intracellular chloride concentrations through balanced activity of Na+-K+-2Cl– cotransporter 1 (NKCC1) and K+-Cl– cotransporter 2 (KCC2). Whereas in other cell types activation of chloride conductances causes hyperpolarization, activation of the same conductances in primary afferent neurons may lead to inhibitory or excitatory depolarization depending on the actual chloride reversal potential and the total amount of chloride efflux during channel or transporter activation. Dorsal root ganglion (DRG) neurons express a multitude of chloride channel types belonging to different channel families, such as ligand-gated, ionotropic γ-aminobutyric acid (GABA) or glycine receptors, Ca2+-activated chloride channels of the anoctamin/TMEM16, bestrophin or tweety-homolog family, CLC chloride channels and transporters, cystic fibrosis transmembrane conductance regulator (CFTR) as well as volume-regulated anion channels (VRACs). Specific chloride conductances are involved in signal transduction and amplification at the peripheral nerve terminal, contribute to excitability and action potential generation of sensory neurons, or crucially shape synaptic transmission in the spinal dorsal horn. In addition, chloride channels can be modified by a plethora of inflammatory mediators affecting them directly, via protein-protein interaction, or through signaling cascades. Since chloride channels as well as mediators that modulate chloride fluxes are regulated in pain disorders and contribute to nociceptor excitation and sensitization it is timely and important to emphasize their critical role in nociceptive primary afferents in this review.
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Affiliation(s)
- Bettina U Wilke
- Institute of Physiology, Department of Physiology and Medical Physics, Medical University of Innsbruck, Innsbruck, Austria
| | - Kai K Kummer
- Institute of Physiology, Department of Physiology and Medical Physics, Medical University of Innsbruck, Innsbruck, Austria
| | - Michael G Leitner
- Institute of Physiology, Department of Physiology and Medical Physics, Medical University of Innsbruck, Innsbruck, Austria
| | - Michaela Kress
- Institute of Physiology, Department of Physiology and Medical Physics, Medical University of Innsbruck, Innsbruck, Austria
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47
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Weinert S, Gimber N, Deuschel D, Stuhlmann T, Puchkov D, Farsi Z, Ludwig CF, Novarino G, López-Cayuqueo KI, Planells-Cases R, Jentsch TJ. Uncoupling endosomal CLC chloride/proton exchange causes severe neurodegeneration. EMBO J 2020; 39:e103358. [PMID: 32118314 PMCID: PMC7196918 DOI: 10.15252/embj.2019103358] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 01/24/2020] [Accepted: 01/27/2020] [Indexed: 01/02/2023] Open
Abstract
CLC chloride/proton exchangers may support acidification of endolysosomes and raise their luminal Cl− concentration. Disruption of endosomal ClC‐3 causes severe neurodegeneration. To assess the importance of ClC‐3 Cl−/H+ exchange, we now generate Clcn3unc/unc mice in which ClC‐3 is converted into a Cl− channel. Unlike Clcn3−/− mice, Clcn3unc/unc mice appear normal owing to compensation by ClC‐4 with which ClC‐3 forms heteromers. ClC‐4 protein levels are strongly reduced in Clcn3−/−, but not in Clcn3unc/unc mice because ClC‐3unc binds and stabilizes ClC‐4 like wild‐type ClC‐3. Although mice lacking ClC‐4 appear healthy, its absence in Clcn3unc/unc/Clcn4−/− mice entails even stronger neurodegeneration than observed in Clcn3−/− mice. A fraction of ClC‐3 is found on synaptic vesicles, but miniature postsynaptic currents and synaptic vesicle acidification are not affected in Clcn3unc/unc or Clcn3−/− mice before neurodegeneration sets in. Both, Cl−/H+‐exchange activity and the stabilizing effect on ClC‐4, are central to the biological function of ClC‐3.
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Affiliation(s)
- Stefanie Weinert
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany.,Max-Delbrück-Centrum für Molekulare Medizin (MDC), Berlin, Germany
| | - Niclas Gimber
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany.,Max-Delbrück-Centrum für Molekulare Medizin (MDC), Berlin, Germany
| | - Dorothea Deuschel
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany.,Max-Delbrück-Centrum für Molekulare Medizin (MDC), Berlin, Germany
| | - Till Stuhlmann
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany.,Max-Delbrück-Centrum für Molekulare Medizin (MDC), Berlin, Germany
| | - Dmytro Puchkov
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany
| | - Zohreh Farsi
- Max-Delbrück-Centrum für Molekulare Medizin (MDC), Berlin, Germany
| | - Carmen F Ludwig
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany.,Max-Delbrück-Centrum für Molekulare Medizin (MDC), Berlin, Germany
| | - Gaia Novarino
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany.,Max-Delbrück-Centrum für Molekulare Medizin (MDC), Berlin, Germany
| | - Karen I López-Cayuqueo
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany.,Max-Delbrück-Centrum für Molekulare Medizin (MDC), Berlin, Germany
| | - Rosa Planells-Cases
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany.,Max-Delbrück-Centrum für Molekulare Medizin (MDC), Berlin, Germany
| | - Thomas J Jentsch
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany.,Max-Delbrück-Centrum für Molekulare Medizin (MDC), Berlin, Germany.,NeuroCure Cluster of Excellence, Charité Universitätsmedizin Berlin, Berlin, Germany
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48
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Nanoparticle-Mediated Therapeutic Application for Modulation of Lysosomal Ion Channels and Functions. Pharmaceutics 2020; 12:pharmaceutics12030217. [PMID: 32131531 PMCID: PMC7150957 DOI: 10.3390/pharmaceutics12030217] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 02/26/2020] [Accepted: 02/27/2020] [Indexed: 02/07/2023] Open
Abstract
Applications of nanoparticles in various fields have been addressed. Nanomaterials serve as carriers for transporting conventional drugs or proteins through lysosomes to various cellular targets. The basic function of lysosomes is to trigger degradation of proteins and lipids. Understanding of lysosomal functions is essential for enhancing the efficacy of nanoparticles-mediated therapy and reducing the malfunctions of cellular metabolism. The lysosomal function is modulated by the movement of ions through various ion channels. Thus, in this review, we have focused on the recruited ion channels for lysosomal function, to understand the lysosomal modulation through the nanoparticles and its applications. In the future, lysosomal channels-based targets will expand the therapeutic application of nanoparticles-associated drugs.
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49
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Wheeler S, Sillence DJ. Niemann-Pick type C disease: cellular pathology and pharmacotherapy. J Neurochem 2019; 153:674-692. [PMID: 31608980 DOI: 10.1111/jnc.14895] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 09/10/2019] [Accepted: 09/15/2019] [Indexed: 12/22/2022]
Abstract
Niemann-Pick type C disease (NPCD) was first described in 1914 and affects approximately 1 in 150 000 live births. It is characterized clinically by diverse symptoms affecting liver, spleen, motor control, and brain; premature death invariably results. Its molecular origins were traced, as late as 1997, to a protein of late endosomes and lysosomes which was named NPC1. Mutation or absence of this protein leads to accumulation of cholesterol in these organelles. In this review, we focus on the intracellular events that drive the pathology of this disease. We first introduce endocytosis, a much-studied area of dysfunction in NPCD cells, and survey the various ways in which this process malfunctions. We briefly consider autophagy before attempting to map the more complex pathways by which lysosomal cholesterol storage leads to protein misregulation, mitochondrial dysfunction, and cell death. We then briefly introduce the metabolic pathways of sphingolipids (as these emerge as key species for treatment) and critically examine the various treatment approaches that have been attempted to date.
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Affiliation(s)
- Simon Wheeler
- School of Pharmacy, De Montfort University, The Gateway, Leicester, UK
| | - Dan J Sillence
- School of Pharmacy, De Montfort University, The Gateway, Leicester, UK
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50
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Pedersen SF, Counillon L. The SLC9A-C Mammalian Na +/H + Exchanger Family: Molecules, Mechanisms, and Physiology. Physiol Rev 2019; 99:2015-2113. [PMID: 31507243 DOI: 10.1152/physrev.00028.2018] [Citation(s) in RCA: 103] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Na+/H+ exchangers play pivotal roles in the control of cell and tissue pH by mediating the electroneutral exchange of Na+ and H+ across cellular membranes. They belong to an ancient family of highly evolutionarily conserved proteins, and they play essential physiological roles in all phyla. In this review, we focus on the mammalian Na+/H+ exchangers (NHEs), the solute carrier (SLC) 9 family. This family of electroneutral transporters constitutes three branches: SLC9A, -B, and -C. Within these, each isoform exhibits distinct tissue expression profiles, regulation, and physiological roles. Some of these transporters are highly studied, with hundreds of original articles, and some are still only rudimentarily understood. In this review, we present and discuss the pioneering original work as well as the current state-of-the-art research on mammalian NHEs. We aim to provide the reader with a comprehensive view of core knowledge and recent insights into each family member, from gene organization over protein structure and regulation to physiological and pathophysiological roles. Particular attention is given to the integrated physiology of NHEs in the main organ systems. We provide several novel analyses and useful overviews, and we pinpoint main remaining enigmas, which we hope will inspire novel research on these highly versatile proteins.
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Affiliation(s)
- S F Pedersen
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark; and Université Côte d'Azur, CNRS, Laboratoire de Physiomédecine Moléculaire, LP2M, France, and Laboratories of Excellence Ion Channel Science and Therapeutics, Nice, France
| | - L Counillon
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark; and Université Côte d'Azur, CNRS, Laboratoire de Physiomédecine Moléculaire, LP2M, France, and Laboratories of Excellence Ion Channel Science and Therapeutics, Nice, France
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