1
|
Wan Y, Guo S, Zhen W, Xu L, Chen X, Liu F, Shen Y, Liu S, Hu L, Wang X, Ye F, Wang Q, Wen H, Yang F. Structural basis of adenine nucleotides regulation and neurodegenerative pathology in ClC-3 exchanger. Nat Commun 2024; 15:6654. [PMID: 39107281 PMCID: PMC11303396 DOI: 10.1038/s41467-024-50975-w] [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: 10/16/2023] [Accepted: 07/25/2024] [Indexed: 08/10/2024] Open
Abstract
The ClC-3 chloride/proton exchanger is both physiologically and pathologically critical, as it is potentiated by ATP to detect metabolic energy level and point mutations in ClC-3 lead to severe neurodegenerative diseases in human. However, why this exchanger is differentially modulated by ATP, ADP or AMP and how mutations caused gain-of-function remains largely unknow. Here we determine the high-resolution structures of dimeric wildtype ClC-3 in the apo state and in complex with ATP, ADP and AMP, and the disease-causing I607T mutant in the apo and ATP-bounded state by cryo-electron microscopy. In combination with patch-clamp recordings and molecular dynamic simulations, we reveal how the adenine nucleotides binds to ClC-3 and changes in ion occupancy between apo and ATP-bounded state. We further observe I607T mutation induced conformational changes and augments in current. Therefore, our study not only lays the structural basis of adenine nucleotides regulation in ClC-3, but also clearly indicates the target region for drug discovery against ClC-3 mediated neurodegenerative diseases.
Collapse
Affiliation(s)
- Yangzhuoqun Wan
- Department of Biophysics and Disease Center of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou, Zhejiang, China
| | - Shuangshuang Guo
- Department of Biophysics and Disease Center of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou, Zhejiang, China
| | - Wenxuan Zhen
- Department of Biophysics and Disease Center of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou, Zhejiang, China
| | - Lizhen Xu
- Department of Biophysics and Disease Center of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou, Zhejiang, China
| | - Xiaoying Chen
- Department of Biophysics and Disease Center of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou, Zhejiang, China
| | - Fangyue Liu
- Department of Neurobiology and Department of General Intensive Care Unit of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Yi Shen
- Department of Neurobiology and Department of General Intensive Care Unit of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Shuangshuang Liu
- Core Facilities, Zhejiang University School of Medicine, Hangzhou, China
| | - Lidan Hu
- The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | | | | | | | - Han Wen
- DP Technology, Beijing, China.
- Institute for Advanced Algorithms Research, Shanghai, China.
- State Key Laboratory of Medical Proteomics, Shanghai, China.
- AI for Science Institute, Beijing, China.
- National Key Laboratory of Lead Druggability Research, Beijing, China.
| | - Fan Yang
- Department of Biophysics and Disease Center of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
- Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou, Zhejiang, China.
| |
Collapse
|
2
|
He H, Li X, Guzman GA, Bungert-Plümke S, Franzen A, Lin X, Zhu H, Peng G, Zhang H, Yu Y, Sun S, Huang Z, Zhai Q, Chen Z, Peng J, Guzman RE. Expanding the genetic and phenotypic relevance of CLCN4 variants in neurodevelopmental condition: 13 new patients. J Neurol 2024; 271:4933-4948. [PMID: 38758281 DOI: 10.1007/s00415-024-12383-4] [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: 02/24/2024] [Revised: 04/02/2024] [Accepted: 04/09/2024] [Indexed: 05/18/2024]
Abstract
OBJECTIVES CLCN4 variations have recently been identified as a genetic cause of X-linked neurodevelopmental disorders. This study aims to broaden the phenotypic spectrum of CLCN4-related condition and correlate it with functional consequences of CLCN4 variants. METHODS We described 13 individuals with CLCN4-related neurodevelopmental disorder. We analyzed the functional consequence of the unreported variants using heterologous expression, biochemistry, confocal fluorescent microscopy, patch-clamp electrophysiology, and minigene splicing assay. RESULTS We identified five novel (p.R41W, p.L348V, p.G480R, p.R603W, c.1576 + 5G > A) and three known (p.T203I, p.V275M, p.A555V) pathogenic CLCN4 variants in 13 Chinese patients. The p.V275M variant is found at high frequency and seen in four unrelated individuals. All had global developmental delay (GDD)/intellectual disability (ID). Seizures were present in eight individuals, and 62.5% of them developed refractory epilepsy. Five individuals without seizures showed moderate to severe GDD/ID. Developmental delay precedes seizure onset in most patients. The variants p.R41W, p.L348V, and p.R603W compromise the anion/exchange function of ClC-4. p.R41W partially impairs ClC-3/ClC-4 association. p.G480R reduces ClC-4 expression levels and impairs the heterodimerization with ClC-3. The c.1576 + 5G > A variant causes 22 bp deletion of exon 10. CONCLUSIONS We further define and broaden the clinical and mutational spectrum of CLCN4-related neurodevelopmental conditions. The p.V275M variant may be a potential hotspot CLCN4 variant in Chinese patients. The five novel variants cause loss of function of ClC-4. Transport dysfunction, protein instability, intracellular trafficking defect, or failure of ClC-4 to oligomerize may contribute to the pathophysiological events leading to CLCN4-related neurodevelopmental disorder.
Collapse
Affiliation(s)
- Hailan He
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Xinyi Li
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - G A Guzman
- Institute of Biological Information Processing (IBI-7), Structural Biochemistry, Jülich Research Center, Jülich, Germany
| | - Stefanie Bungert-Plümke
- Institute of Biological Information Processing (IBI-1), Molecular and Cell Physiology, Jülich Research Center, Jülich, Germany
| | - Arne Franzen
- Institute of Biological Information Processing (IBI-1), Molecular and Cell Physiology, Jülich Research Center, Jülich, Germany
| | - XueQin Lin
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Hongmin Zhu
- Department of Rehabilitation, Wuhan Children's Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China
| | - Guilan Peng
- Department of Neurology, Xiamen Maternal and Child Health Care Hospital, Xiamen, China
| | - Hongwei Zhang
- Epilepsy Center, Children's Hospital Affiliated to Shandong University, Jinan, China
| | - Yonglin Yu
- Department of Rehabilitation, Children's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Suzhen Sun
- Department of Pediatric Neurology, Hebei Children's Hospital, Hebei Medical University, Shijiazhuang, China
| | - Zhongqin Huang
- Department of Neurology, Xiamen Maternal and Child Health Care Hospital, Xiamen, China
| | - Qiongxiang Zhai
- Department of Pediatrics, Guangdong Provincial People's Hospital, Guangzhou, China
| | - Zheng Chen
- Department of Pediatrics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Jing Peng
- 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.
| |
Collapse
|
3
|
Tourkova IL, Larrouture QC, Liu S, Luo J, Shipman KE, Onwuka KM, Weisz OA, Riazanski V, Nelson DJ, MacDonald ML, Schlesinger PH, Blair HC. Chloride/proton antiporters ClC3 and ClC5 support bone formation in mice. Bone Rep 2024; 21:101763. [PMID: 38666049 PMCID: PMC11043850 DOI: 10.1016/j.bonr.2024.101763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Accepted: 04/12/2024] [Indexed: 04/28/2024] Open
Abstract
Acid transport is required for bone synthesis by osteoblasts. The osteoblast basolateral surface extrudes acid by Na+/H+ exchange, but apical proton uptake is undefined. We found high expression of the Cl-/H+ exchanger ClC3 at the bone apical surface. In mammals ClC3 functions in intracellular vesicular chloride transport, but when we found Cl- dependency of H+ transport in osteoblast membranes, we queried whether ClC3 Cl-/H+ exchange functions in bone formation. We used ClC3 knockout animals, and closely-related ClC5 knockout animals: In vitro studies suggested that both ClC3 and ClC5 might support bone formation. Genotypes were confirmed by total exon sequences. Expression of ClC3, and to a lesser extent of ClC5, at osteoblast apical membranes was demonstrated by fluorescent antibody labeling and electron microscopy with nanometer gold labeling. Animals with ClC3 or ClC5 knockouts were viable. In ClC3 or ClC5 knockouts, bone formation decreased ~40 % by calcein and xylenol orange labeling in vivo. In very sensitive micro-computed tomography, ClC5 knockout reduced bone relative to wild type, consistent with effects of ClC3 knockout, but varied with specific histological parameters. Regrettably, ClC5-ClC3 double knockouts are not viable, suggesting that ClC3 or ClC5 activity are essential to life. We conclude that ClC3 has a direct role in bone formation with overlapping but probably slightly smaller effects of ClC5. The mechanism in mineral formation might include ClC H+ uptake, in contrast to ClC3 and ClC5 function in cell vesicles or other organs.
Collapse
Affiliation(s)
- Irina L. Tourkova
- Department of Pathology, University of Pittsburgh, Pittsburgh, PA, USA
- Research Service, VA Healthcare System, Pittsburgh, PA, USA
| | | | - Silvia Liu
- Department of Pathology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Jianhua Luo
- Department of Pathology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Katherine E. Shipman
- Renal Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Kelechi M. Onwuka
- Department of Pathology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Ora A. Weisz
- Renal Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Vladimir Riazanski
- Dept of Neurobiology, Pharmacology & Physiology, University of Chicago, Chicago, IL, USA
| | - Deborah J. Nelson
- Dept of Neurobiology, Pharmacology & Physiology, University of Chicago, Chicago, IL, USA
| | - Matthew L. MacDonald
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | | | - Harry C. Blair
- Department of Pathology, University of Pittsburgh, Pittsburgh, PA, USA
- Research Service, VA Healthcare System, Pittsburgh, PA, USA
| |
Collapse
|
4
|
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.
Collapse
Affiliation(s)
- Alessandra Picollo
- Institute of Biophysics, National Research Council, Genova, Italy
- RAISE Ecosystem, Genova, Italy
| |
Collapse
|
5
|
Stark RJ, Nguyen HN, Bacon MK, Rohrbough JC, Choi H, Lamb FS. Chloride Channel-3 (ClC-3) Modifies the Trafficking of Leucine-Rich Repeat-Containing 8A (LRRC8A) Anion Channels. J Membr Biol 2022; 256:125-135. [PMID: 36322172 PMCID: PMC10085862 DOI: 10.1007/s00232-022-00271-9] [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: 08/05/2022] [Accepted: 09/16/2022] [Indexed: 11/07/2022]
Abstract
Chloride channel-3 (ClC-3) Cl-/H+ antiporters and leucine-rich repeat-containing 8 (LRRC8) family anion channels have both been associated with volume-regulated anion currents (VRACs). VRACs are often altered in ClC-3 null cells but are absent in LRRC8A null cells. To explore the relationship between ClC-3, LRRC8A, and VRAC we localized tagged proteins in human epithelial kidney (HEK293) cells using multimodal microscopy. Expression of ClC-3-GFP induced large multivesicular bodies (MVBs) with ClC-3 in the delimiting membrane. LRRC8A-RFP localized to the plasma membrane and to small cytoplasmic vesicles. Co-expression demonstrated co-localization in small, highly mobile cytoplasmic vesicles that associated with the early endosomal marker Rab5A. However, most of the small LRRC8A-positive vesicles were constrained within large MVBs with abundant ClC-3 in the delimiting membrane. Dominant negative (S34A) Rab5A prevented ClC-3 overexpression from creating enlarged MVBs, while constitutively active (Q79L) Rab5A enhanced this phenotype. Thus, ClC-3 and LRRC8A are endocytosed together but independently sorted in Rab5A MVBs. Subsequently, LRRC8A-labeled vesicles were sorted to MVBs labeled by Rab27A and B exosomal compartment markers, but not to Rab11 recycling endosomes. VRAC currents were significantly larger in ClC-3 null HEK293 cells. This work demonstrates dependence of LRRC8A trafficking on ClC-3 which may explain the association between ClC-3 and VRACs.
Collapse
Affiliation(s)
- Ryan J Stark
- Department of Pediatrics, Vanderbilt University Medical Center, 2215 Garland Avenue, Light Hall-1055D, Nashville, TN, 37232-3122v, USA
| | - Hong N Nguyen
- Department of Pediatrics, Vanderbilt University Medical Center, 2215 Garland Avenue, Light Hall-1055D, Nashville, TN, 37232-3122v, USA
| | - Matthew K Bacon
- Department of Pediatrics, University of Kentucky, Lexington, KY, 40536, USA
| | - Jeffrey C Rohrbough
- Department of Pediatrics, Vanderbilt University Medical Center, 2215 Garland Avenue, Light Hall-1055D, Nashville, TN, 37232-3122v, USA
| | - Hyehun Choi
- Department of Pediatrics, Vanderbilt University Medical Center, 2215 Garland Avenue, Light Hall-1055D, Nashville, TN, 37232-3122v, USA
| | - Fred S Lamb
- Department of Pediatrics, Vanderbilt University Medical Center, 2215 Garland Avenue, Light Hall-1055D, Nashville, TN, 37232-3122v, USA.
| |
Collapse
|
6
|
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.
Collapse
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,
| |
Collapse
|
7
|
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.
Collapse
|
8
|
Gao AYL, Lourdin-De Filippis E, Orlowski J, McKinney RA. Roles of Endomembrane Alkali Cation/Proton Exchangers in Synaptic Function and Neurodevelopmental Disorders. Front Physiol 2022; 13:892196. [PMID: 35547574 PMCID: PMC9081726 DOI: 10.3389/fphys.2022.892196] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 03/30/2022] [Indexed: 12/25/2022] Open
Abstract
Endomembrane alkali cation (Na+, K+)/proton (H+) exchangers (eNHEs) are increasingly associated with neurological disorders. These eNHEs play integral roles in regulating the luminal pH, processing, and trafficking of cargo along the secretory (Golgi and post-Golgi vesicles) and endocytic (early, recycling, and late endosomes) pathways, essential regulatory processes vital for neuronal development and plasticity. Given the complex morphology and compartmentalization of multipolar neurons, the contribution of eNHEs in maintaining optimal pH homeostasis and cargo trafficking is especially significant during periods of structural and functional development and remodeling. While the importance of eNHEs has been demonstrated in a variety of non-neuronal cell types, their involvement in neuronal function is less well understood. In this review, we will discuss their emerging roles in excitatory synaptic function, particularly as it pertains to cellular learning and remodeling. We will also explore their connections to neurodevelopmental conditions, including intellectual disability, autism, and attention deficit hyperactivity disorders.
Collapse
Affiliation(s)
- Andy Y L Gao
- Integrated Program in Neuroscience, McGill University, Montreal, QC, Canada.,Department of Pharmacology & Therapeutics, McGill University, Montreal, QC, Canada
| | | | - John Orlowski
- Department of Physiology, McGill University, Montreal, QC, Canada
| | - R Anne McKinney
- Department of Pharmacology & Therapeutics, McGill University, Montreal, QC, Canada
| |
Collapse
|
9
|
Excess iodide-induced reactive oxygen species elicit iodide efflux via β-tubulin-associated ClC-3 in thyrocytes. Biochem J 2022; 479:629-640. [PMID: 35175311 DOI: 10.1042/bcj20210709] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 01/30/2022] [Accepted: 02/17/2022] [Indexed: 11/17/2022]
Abstract
Iodide (I-) is crucial to thyroid function, and its regulation in thyrocytes involves ion transporters and reactive oxygen species (ROS). However, the extent of 2Cl-/H+ exchanger (ClC-3) involvement in the iodide (I-) efflux from thyrocytes remains unclear. Therefore, we examined the effects of ClC-3 on I- efflux. ClC-3 expression was found to significantly alter the serum TT3 and TT4 concentrations in mice. We further found that excess I- stimulation affected ClC-3 expression, distribution, and I- efflux in FRTL-5 cells. Immunofluorescence analyses indicated that ClC-3 mainly accumulated in the cell membrane and co-localized with β-tubulins after 24 h of excess I- treatment, and that this process depended on ROS production. Thus, ClC-3 may be involved in I- efflux at the apical pole of thyrocytes via excess I--induced ROS production and β-tubulin polymerization. Our results reveal novel insights into the role of ClC-3 in I- transport and thyroid function.
Collapse
|
10
|
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.
Collapse
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.
| |
Collapse
|
11
|
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.
Collapse
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
| |
Collapse
|
12
|
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.
Collapse
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.)
| |
Collapse
|
13
|
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.
Collapse
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.
| |
Collapse
|
14
|
Gu Z, Wang L, Yao X, Long Q, Lee K, Li J, Yue D, Yang S, Liu Y, Li N, Li Y. ClC-3/SGK1 regulatory axis enhances the olaparib-induced antitumor effect in human stomach adenocarcinoma. Cell Death Dis 2020; 11:898. [PMID: 33093458 PMCID: PMC7583252 DOI: 10.1038/s41419-020-03107-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 10/06/2020] [Accepted: 10/07/2020] [Indexed: 12/14/2022]
Abstract
Currently, only a few available targeted drugs are considered to be effective in stomach adenocarcinoma (STAD) treatment. The PARP inhibitor olaparib is a molecularly targeted drug that continues to be investigated in BRCA-mutated tumors. However, in tumors without BRCA gene mutations, particularly in STAD, the effect and molecular mechanism of olaparib are unclear, which largely restricts the use of olaparib in STAD treatment. In this study, the in vitro results showed that olaparib specifically inhibited cell growth and migration, exerting antitumor effect in STAD cell lines. In addition, a ClC-3/SGK1 regulatory axis was identified and validated in STAD cells. We then found that the down-regulation of ClC-3/SGK1 axis attenuated olaparib-induced cell growth and migration inhibition. On the contrary, the up-regulation of ClC-3/SGK1 axis enhanced olaparib-induced cell growth and migration inhibition, and the enhancement effect could be attenuated by SGK1 knockdown. Consistently, the whole-cell recorded chloride current activated by olaparib presented the same variation trend. Next, the clinical data showed that ClC-3 and SGK1 were highly expressed in human STAD tissues and positively correlated (r = 0.276, P = 0.009). Furthermore, high protein expression of both ClC-3 (P = 0.030) and SGK1 (P = 0.006) was associated with poor survival rate in STAD patients, and positive correlations between ClC-3/SGK1 and their downstream molecules in STAD tissues were demonstrated via the GEPIA datasets. Finally, our results suggested that olaparib inhibited the PI3K/AKT pathway in STAD cells, and up-regulation of ClC-3/SGK1 axis enhanced olaparib-induced PI3K/AKT pathway inhibition. The animal experiments indicated that olaparib also exerted antitumor effect in vivo. Altogether, our findings illustrate that olaparib exerts antitumor effect in human STAD, and ClC-3/SGK1 regulatory axis enhances the olaparib-induced antitumor effect. Up-regulation of the ClC-3/SGK1 axis may provide promising therapeutic potential for the clinical application of olaparib in STAD treatment.
Collapse
Affiliation(s)
- Zhuoyu Gu
- Medical Research Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China
| | - Liping Wang
- Department of Clinical Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China
| | - Xiaohan Yao
- Medical Research Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China
| | - Qian Long
- Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center of Cancer Medicine, Guangzhou, China
| | - Kaping Lee
- Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center of Cancer Medicine, Guangzhou, China
| | - Jieyao Li
- Department of Clinical Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China
| | - Dongli Yue
- Department of Clinical Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China
| | - Shuangning Yang
- Department of Clinical Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China
| | - Yanfen Liu
- Department of Clinical Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China
| | - Na Li
- Department of Cardiovascular Medicine, Qingdao No. 9 People's Hospital, Shandong, China
| | - Yixin Li
- Department of Clinical Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China.
| |
Collapse
|
15
|
Lamb FS, Choi H, Miller MR, Stark RJ. TNFα and Reactive Oxygen Signaling in Vascular Smooth Muscle Cells in Hypertension and Atherosclerosis. Am J Hypertens 2020; 33:902-913. [PMID: 32498083 DOI: 10.1093/ajh/hpaa089] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Revised: 05/28/2020] [Accepted: 05/29/2020] [Indexed: 12/16/2022] Open
Abstract
Hypertension and atherosclerosis, the predecessors of stroke and myocardial infarction, are chronic vascular inflammatory reactions. Tumor necrosis factor alpha (TNFα), the "master" proinflammatory cytokine, contributes to both the initiation and maintenance of vascular inflammation. TNFα induces reactive oxygen species (ROS) production which drives the redox reactions that constitute "ROS signaling." However, these ROS may also cause oxidative stress which contributes to vascular dysfunction. Mice lacking TNFα or its receptors are protected against both acute and chronic cardiovascular injury. Humans suffering from TNFα-driven inflammatory conditions such as rheumatoid arthritis and psoriasis are at increased cardiovascular risk. When treated with highly specific biologic agents that target TNFα signaling (Etanercept, etc.) they display marked reductions in that risk. The ability of TNFα to induce endothelial dysfunction, often the first step in a progression toward serious vasculopathy, is well recognized and has been reviewed elsewhere. However, TNFα also has profound effects on vascular smooth muscle cells (VSMCs) including a fundamental change from a contractile to a secretory phenotype. This "phenotypic switching" promotes proliferation and production of extracellular matrix proteins which are associated with medial hypertrophy. Additionally, it promotes lipid storage and enhanced motility, changes that support the contribution of VSMCs to neointima and atherosclerotic plaque formation. This review focuses on the role of TNFα in driving the inflammatory changes in VSMC biology that contribute to cardiovascular disease. Special attention is given to the mechanisms by which TNFα promotes ROS production at specific subcellular locations, and the contribution of these ROS to TNFα signaling.
Collapse
Affiliation(s)
- Fred S Lamb
- Division of Pediatric Critical Care, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Hyehun Choi
- Division of Pediatric Critical Care, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Michael R Miller
- Division of Pediatric Critical Care, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Ryan J Stark
- Division of Pediatric Critical Care, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| |
Collapse
|
16
|
Grieschat M, Guzman RE, Langschwager K, Fahlke C, Alekov AK. Metabolic energy sensing by mammalian CLC anion/proton exchangers. EMBO Rep 2020; 21:e47872. [PMID: 32390228 PMCID: PMC7271328 DOI: 10.15252/embr.201947872] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Revised: 01/26/2020] [Accepted: 01/29/2020] [Indexed: 12/13/2022] Open
Abstract
CLC anion/proton exchangers control the pH and [Cl- ] of the endolysosomal system that is essential for cellular nutrient uptake. Here, we use heterologous expression and whole-cell electrophysiology to investigate the regulation of the CLC isoforms ClC-3, ClC-4, and ClC-5 by the adenylic system components ATP, ADP, and AMP. Our results show that cytosolic ATP and ADP but not AMP and Mg2+ -free ADP enhance CLC ion transport. Biophysical analysis reveals that adenine nucleotides alter the ratio between CLC ion transport and CLC gating charge and shift the CLC voltage-dependent activation. The latter effect is suppressed by blocking the intracellular entrance of the proton transport pathway. We suggest, therefore, that adenine nucleotides regulate the internal proton delivery into the CLC transporter machinery and alter the probability of CLC transporters to undergo silent non-transporting cycles. Our findings suggest that the CBS domains in mammalian CLC transporters serve as energy sensors that regulate vesicular Cl- /H+ exchange by detecting changes in the cytosolic ATP/ADP/AMP equilibrium. Such sensing mechanism links the endolysosomal activity to the cellular metabolic state.
Collapse
Affiliation(s)
| | - Raul E Guzman
- Institute of Complex SystemsZelluläre Biophysik (ICS‐4), Forschungszentrum JülichJülichGermany
| | | | - Christoph Fahlke
- Institute of Complex SystemsZelluläre Biophysik (ICS‐4), Forschungszentrum JülichJülichGermany
| | - Alexi K Alekov
- Institute of NeurophysiologyHannover Medical SchoolHannoverGermany
| |
Collapse
|
17
|
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.
Collapse
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
| |
Collapse
|
18
|
Araújo CET, Oliveira CMC, Barbosa JD, Oliveira-Filho JP, Resende LAL, Badial PR, Araujo-Junior JP, McCue ME, Borges AS. A large intragenic deletion in the CLCN1 gene causes Hereditary Myotonia in pigs. Sci Rep 2019; 9:15632. [PMID: 31666547 PMCID: PMC6821760 DOI: 10.1038/s41598-019-51286-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 09/11/2019] [Indexed: 12/14/2022] Open
Abstract
Mutations in the CLCN1 gene are the primary cause of non-dystrophic Hereditary Myotonia in several animal species. However, there are no reports of Hereditary Myotonia in pigs to date. Therefore, the objective of the present study was to characterize the clinical and molecular findings of Hereditary Myotonia in an inbred pedigree. The clinical, electromyographic, histopathological, and molecular findings were evaluated. Clinically affected pigs presented non-dystrophic recessive Hereditary Myotonia. Nucleotide sequence analysis of the entire coding region of the CLCN1 gene revealed the absence of the exons 15 and 16 in myotonic animals. Analysis of the genomic region flanking the deletion unveiled a large intragenic deletion of 4,165 nucleotides. Interestingly, non-related, non-myotonic pigs expressed transcriptional levels of an alternate transcript (i.e., X2) that was identical to the deleted X1 transcript of myotonic pigs. All myotonic pigs and their progenitors were homozygous recessive and heterozygous, respectively, for the 4,165-nucleotide deletion. This is the first study reporting Hereditary Myotonia in pigs and characterizing its clinical and molecular findings. Moreover, to the best of our knowledge, Hereditary Myotonia has never been associated with a genomic deletion in the CLCN1 gene in any other species.
Collapse
Affiliation(s)
- C E T Araújo
- São Paulo State University (UNESP), School of Veterinary Medicine and Animal Science, Botucatu, São Paulo, Brazil
| | - C M C Oliveira
- Instituto de Medicina Veterinária, Universidade Federal do Pará, Campus Castanhal, PA, Brazil
| | - J D Barbosa
- Instituto de Medicina Veterinária, Universidade Federal do Pará, Campus Castanhal, PA, Brazil
| | - J P Oliveira-Filho
- São Paulo State University (UNESP), School of Veterinary Medicine and Animal Science, Botucatu, São Paulo, Brazil
| | - L A L Resende
- São Paulo State University (UNESP), Medical School, Botucatu, Brazil
| | - P R Badial
- Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Starkville, MS, USA
| | - J P Araujo-Junior
- São Paulo State University (UNESP), Institute of Bioscience, Botucatu, Brazil
| | - M E McCue
- College of Veterinary Medicine, University of Minnesota, St Paul, Minnesota, 55108, USA
| | - A S Borges
- São Paulo State University (UNESP), School of Veterinary Medicine and Animal Science, Botucatu, São Paulo, Brazil.
| |
Collapse
|
19
|
Schlesinger PH, Blair HC, Beer Stolz D, Riazanski V, Ray EC, Tourkova IL, Nelson DJ. Cellular and extracellular matrix of bone, with principles of synthesis and dependency of mineral deposition on cell membrane transport. Am J Physiol Cell Physiol 2019; 318:C111-C124. [PMID: 31532718 DOI: 10.1152/ajpcell.00120.2019] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Bone differs from other connective tissues; it is isolated by a layer of osteoblasts that are connected by tight and gap junctions. This allows bone to create dense lamellar type I collagen, control pH, mineral deposition, and regulate water content forming a compact and strong structure. New woven bone formed after degradation of mineralized cartilage is rapidly degraded and resynthesized to impart structural order for local bone strength. Ossification is regulated by thickness of bone units and by patterning via bone morphogenetic receptors including activin, other bone morphogenetic protein receptors, transforming growth factor-β receptors, all part of a receptor superfamily. This superfamily interacts with receptors for additional signals in bone differentiation. Important features of the osteoblast environment were established using recent tools including osteoblast differentiation in vitro. Osteoblasts deposit matrix protein, over 90% type I collagen, in lamellae with orientation alternating parallel or orthogonal to the main stress axis of the bone. Into this organic matrix, mineral is deposited as hydroxyapatite. Mineral matrix matures from amorphous to crystalline hydroxyapatite. This process includes at least two-phase changes of the calcium-phosphate mineral as well as intermediates involving tropocollagen fibrils to form the bone composite. Beginning with initiation of mineral deposition, there is uncertainty regarding cardinal processes, but the driving force is not merely exceeding the calcium-phosphate solubility product. It occurs behind a epithelial-like layer of osteoblasts, which generate phosphate and remove protons liberated during calcium-phosphate salt deposition. The forming bone matrix is discontinuous from the general extracellular fluid. Required adjustment of ionic concentrations and water removal from bone matrix are important details remaining to be addressed.
Collapse
Affiliation(s)
| | - Harry C Blair
- Veterans Affairs Medical Center, Pittsburgh, Pennsylvania.,Department of Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Donna Beer Stolz
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Vladimir Riazanski
- Department of Neurobiology, Pharmacology, and Physiology, University of Chicago, Chicago, Illinois
| | - Evan C Ray
- Renal Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Irina L Tourkova
- Veterans Affairs Medical Center, Pittsburgh, Pennsylvania.,Department of Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Deborah J Nelson
- Department of Neurobiology, Pharmacology, and Physiology, University of Chicago, Chicago, Illinois
| |
Collapse
|
20
|
Starvation-induced autophagy is up-regulated via ROS-mediated ClC-3 chloride channel activation in the nasopharyngeal carcinoma cell line CNE-2Z. Biochem J 2019; 476:1323-1333. [DOI: 10.1042/bcj20180979] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 04/13/2019] [Accepted: 04/16/2019] [Indexed: 01/15/2023]
Abstract
Abstract
Nutrient deficiency develops frequently in nasopharyngeal carcinoma cell (CNE-2Z) due to the characteristics of aggregation and uncontrolled proliferation. Therefore, starvation can induce autophagy in these cells. Chloride channel 3 (ClC-3), a member of the chloride channel family, is involved in various biological processes. However, whether ClC-3 plays an important role in starvation-induced autophagy is unclear. In this study, Earle's balanced salt solution (EBSS) was used to induce autophagy in CNE-2Z cells. We found that autophagy and the chloride current induced by EBSS were inhibited by chloride channel blockers. ClC-3 knockdown inhibited the degradation of LC3-II and P62. Furthermore, when reactive oxygen species (ROS) generation was suppressed by antioxidant N-acetyl-l-cysteine (L-NAC) pretreatment, EBSS-induced autophagy was inhibited, and the chloride current was unable to be activated. Nevertheless, ClC-3 knockdown had little effect on ROS levels, indicating that ROS acted upstream of ClC-3 and that both ROS and ClC-3 participated in EBSS-induced autophagy regulation in CNE-2Z.
Collapse
|
21
|
Chen Q, Liu X, Luo Z, Wang S, Lin J, Xie Z, Li M, Li C, Cao H, Huang Q, Mao J, Xu B. Chloride channel-3 mediates multidrug resistance of cancer by upregulating P-glycoprotein expression. J Cell Physiol 2018; 234:6611-6623. [PMID: 30230544 DOI: 10.1002/jcp.27402] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 08/17/2018] [Indexed: 12/20/2022]
Abstract
Chloride channel-3 (ClC-3), a member of the ClC family of voltage-gated Cl- channels, is involved in the resistance of tumor cells to chemotherapeutic drugs. Here, we report a new mechanism for ClC-3 in mediating multidrug resistance (MDR). ClC-3 was highly expressed in the P-glycoprotein (P-gp)-dependent human lung adenocarcinoma cell line (A549)/paclitaxel (PTX) and the human breast carcinoma cell line (MCF-7)/doxorubicin (DOX) resistant cells. Changes in the ClC-3 expression resulted in the development of drug resistance in formerly drug-sensitive A549 or MCF-7 cells, and drug sensitivity in formerly drug-resistant A549/Taxol and MCF-7/DOX cells. Double transgenic MMTV-PyMT/CLCN3 mice with spontaneous mammary cancer and ClC-3 overexpression demonstrated drug resistance to PTX and DOX. ClC-3 expression upregulated the expression of MDR1 messenger RNA and P-gp by activating the nuclear factor-κB (NF-κB)-signaling pathway. These data suggest that ClC-3 expression in cancer cells induces MDR by upregulating NF-κB-signaling-dependent P-gp expression involving another new mechanism for ClC-3 in the development of drug resistance of cancers.
Collapse
Affiliation(s)
- Qi Chen
- Guangdong Provincial Key Laboratory of Pharmaceutical Bioactive Substances and School of Basic Medicine, Guangdong Pharmaceutical University, Guangzhou, China
| | - Xueqiang Liu
- Guangdong Province Key Laboratory for Biotechnology Drug Candidates and School of Biosciences and Biopharmaceutics, Guangdong Pharmaceutical University, Guangzhou, China
| | - Zhesi Luo
- Guangdong Provincial Key Laboratory of Pharmaceutical Bioactive Substances and School of Basic Medicine, Guangdong Pharmaceutical University, Guangzhou, China
| | - Shisi Wang
- Guangdong Province Key Laboratory for Biotechnology Drug Candidates and School of Biosciences and Biopharmaceutics, Guangdong Pharmaceutical University, Guangzhou, China
| | - Jialin Lin
- Guangdong Province Key Laboratory for Biotechnology Drug Candidates and School of Biosciences and Biopharmaceutics, Guangdong Pharmaceutical University, Guangzhou, China
| | - Zheng Xie
- Guangdong Provincial Key Laboratory of Pharmaceutical Bioactive Substances and School of Basic Medicine, Guangdong Pharmaceutical University, Guangzhou, China
| | - Mengge Li
- Guangdong Provincial Key Laboratory of Pharmaceutical Bioactive Substances and School of Basic Medicine, Guangdong Pharmaceutical University, Guangzhou, China
| | - Chunmei Li
- Guangdong Provincial Key Laboratory of Pharmaceutical Bioactive Substances and School of Basic Medicine, Guangdong Pharmaceutical University, Guangzhou, China
| | - Hua Cao
- School of Chemistry and Chemical Engineering, Guangdong Pharmaceutical University, Zhongshan, China
| | - Qingsong Huang
- Guangdong Provincial Key Laboratory of Pharmaceutical Bioactive Substances and School of Basic Medicine, Guangdong Pharmaceutical University, Guangzhou, China
| | - Jianwen Mao
- Guangdong Provincial Key Laboratory of Pharmaceutical Bioactive Substances and School of Basic Medicine, Guangdong Pharmaceutical University, Guangzhou, China
| | - Bin Xu
- Guangdong Provincial Key Laboratory of Pharmaceutical Bioactive Substances and School of Basic Medicine, Guangdong Pharmaceutical University, Guangzhou, China.,Guangdong Province Key Laboratory for Biotechnology Drug Candidates and School of Biosciences and Biopharmaceutics, Guangdong Pharmaceutical University, Guangzhou, China
| |
Collapse
|
22
|
Guzman RE, Fahlke C. ClC-3: biophysical properties clarify cellular functions. J Physiol 2018; 596:3823-3824. [PMID: 29974478 DOI: 10.1113/jp276670] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- Raul E Guzman
- Institute of Complex Systems - Zelluläre Biophysik (ICS-4), Forschungszentrum Jülich, Jülich, 52425, Germany
| | - Christoph Fahlke
- Institute of Complex Systems - Zelluläre Biophysik (ICS-4), Forschungszentrum Jülich, Jülich, 52425, Germany
| |
Collapse
|