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Regulation of Neuronal Na,K-ATPase by Extracellular Scaffolding Proteins. Int J Mol Sci 2018; 19:ijms19082214. [PMID: 30060621 PMCID: PMC6121408 DOI: 10.3390/ijms19082214] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 07/24/2018] [Accepted: 07/25/2018] [Indexed: 12/19/2022] Open
Abstract
Neuronal activity leads to an influx of Na⁺ that needs to be rapidly cleared. The sodium-potassium ATPase (Na,K-ATPase) exports three Na⁺ ions and imports two K⁺ ions at the expense of one ATP molecule. Na,K-ATPase turnover accounts for the majority of energy used by the brain. To prevent an energy crisis, the energy expense for Na⁺ clearance must provide an optimal effect. Here we report that in rat primary hippocampal neurons, the clearance of Na⁺ ions is more efficient if Na,K-ATPase is laterally mobile in the membrane than if it is clustered. Using fluorescence recovery after photobleaching and single particle tracking analysis, we show that the ubiquitous α1 and the neuron-specific α3 catalytic subunits as well as the supportive β1 subunit of Na,K-ATPase are highly mobile in the plasma membrane. We show that cross-linking of the β1 subunit with polyclonal antibodies or exposure to Modulator of Na,K-ATPase (MONaKA), a secreted protein which binds to the extracellular domain of the β subunit, clusters the α3 subunit in the membrane and restricts its mobility. We demonstrate that clustering, caused by cross-linking or by exposure to MONaKA, reduces the efficiency in restoring intracellular Na⁺. These results demonstrate that extracellular interactions with Na,K-ATPase regulate the Na⁺ extrusion efficiency with consequences for neuronal energy balance.
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Balasubramaniam SL, Gopalakrishnapillai A, Petrelli NJ, Barwe SP. Knockdown of sodium-calcium exchanger 1 induces epithelial-to-mesenchymal transition in kidney epithelial cells. J Biol Chem 2017; 292:11388-11399. [PMID: 28550085 DOI: 10.1074/jbc.m116.752352] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 05/17/2017] [Indexed: 12/17/2022] Open
Abstract
Mesenchymal-to-epithelial transition (MET) and epithelial-to-mesenchymal transition (EMT) are important processes in kidney development. Failure to undergo MET during development leads to the initiation of Wilms tumor, whereas EMT contributes to the development of renal cell carcinomas (RCC). The role of calcium regulators in governing these processes is becoming evident. We demonstrated earlier that Na+/Ca2+ exchanger 1 (NCX1), a major calcium exporter in renal epithelial cells, regulates epithelial cell motility. Here, we show for the first time that NCX1 mRNA and protein expression was down-regulated in Wilms tumor and RCC. Knockdown of NCX1 in Madin-Darby canine kidney cells induced fibroblastic morphology, increased intercellular junctional distance, and induced paracellular permeability, loss of apico-basal polarity in 3D cultures, and anchorage-independent growth, accompanied by expression of mesenchymal markers. We also provide evidence that NCX1 interacts with and anchors E-cadherin to the cell surface independent of NCX1 ion transport activity. Consistent with destabilization of E-cadherin, NCX1 knockdown cells showed an increase in β-catenin nuclear localization, enhanced transcriptional activity, and up-regulation of downstream targets of the β-catenin signaling pathway. Taken together, knockdown of NCX1 in Madin-Darby canine kidney cells alters epithelial morphology and characteristics by destabilization of E-cadherin and induction of β-catenin signaling.
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Affiliation(s)
- Sona Lakshme Balasubramaniam
- From the Nemours Center for Childhood Cancer Research, Alfred I. duPont Hospital for Children, Wilmington, Delaware 19803.,the Department of Biological Sciences, University of Delaware, Newark, Delaware 19716, and
| | - Anilkumar Gopalakrishnapillai
- From the Nemours Center for Childhood Cancer Research, Alfred I. duPont Hospital for Children, Wilmington, Delaware 19803
| | - Nicholas J Petrelli
- the Helen F. Graham Cancer Center, Christiana Care Health System, Newark, Delaware 19718
| | - Sonali P Barwe
- From the Nemours Center for Childhood Cancer Research, Alfred I. duPont Hospital for Children, Wilmington, Delaware 19803, .,the Department of Biological Sciences, University of Delaware, Newark, Delaware 19716, and
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3
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Tokhtaeva E, Sun H, Deiss-Yehiely N, Wen Y, Soni PN, Gabrielli NM, Marcus EA, Ridge KM, Sachs G, Vazquez-Levin M, Sznajder JI, Vagin O, Dada LA. The O-glycosylated ectodomain of FXYD5 impairs adhesion by disrupting cell-cell trans-dimerization of Na,K-ATPase β1 subunits. J Cell Sci 2016; 129:2394-406. [PMID: 27142834 DOI: 10.1242/jcs.186148] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 04/26/2016] [Indexed: 12/24/2022] Open
Abstract
FXYD5 (also known as dysadherin), a regulatory subunit of the Na,K-ATPase, impairs intercellular adhesion by a poorly understood mechanism. Here, we determined whether FXYD5 disrupts the trans-dimerization of Na,K-ATPase molecules located in neighboring cells. Mutagenesis of the Na,K-ATPase β1 subunit identified four conserved residues, including Y199, that are crucial for the intercellular Na,K-ATPase trans-dimerization and adhesion. Modulation of expression of FXYD5 or of the β1 subunit with intact or mutated β1-β1 binding sites demonstrated that the anti-adhesive effect of FXYD5 depends on the presence of Y199 in the β1 subunit. Immunodetection of the plasma membrane FXYD5 was prevented by the presence of O-glycans. Partial FXYD5 deglycosylation enabled antibody binding and showed that the protein level and the degree of O-glycosylation were greater in cancer than in normal cells. FXYD5-induced impairment of adhesion was abolished by both genetic and pharmacological inhibition of FXYD5 O-glycosylation. Therefore, the extracellular O-glycosylated domain of FXYD5 impairs adhesion by interfering with intercellular β1-β1 interactions, suggesting that the ratio between FXYD5 and α1-β1 heterodimer determines whether the Na,K-ATPase acts as a positive or negative regulator of intercellular adhesion.
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Affiliation(s)
- Elmira Tokhtaeva
- Department of Physiology, David Geffen School of Medicine, UCLA, Los Angeles, CA 90095, USA Veterans Administration Greater Los Angeles Healthcare System, Los Angeles, CA 90095, USA
| | - Haying Sun
- Division of Pulmonary and Critical Care Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Nimrod Deiss-Yehiely
- Division of Pulmonary and Critical Care Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Yi Wen
- Department of Physiology, David Geffen School of Medicine, UCLA, Los Angeles, CA 90095, USA Veterans Administration Greater Los Angeles Healthcare System, Los Angeles, CA 90095, USA
| | - Pritin N Soni
- Division of Pulmonary and Critical Care Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Nieves M Gabrielli
- Division of Pulmonary and Critical Care Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA Instituto de Biología y Medicina Experimental (CONICET-FIBYME), Buenos Aires C1418ADN, Argentina
| | - Elizabeth A Marcus
- Veterans Administration Greater Los Angeles Healthcare System, Los Angeles, CA 90095, USA Department of Pediatrics, David Geffen School of Medicine, UCLA, Los Angeles, CA 90095, USA
| | - Karen M Ridge
- Division of Pulmonary and Critical Care Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - George Sachs
- Department of Physiology, David Geffen School of Medicine, UCLA, Los Angeles, CA 90095, USA Veterans Administration Greater Los Angeles Healthcare System, Los Angeles, CA 90095, USA
| | - Mónica Vazquez-Levin
- Instituto de Biología y Medicina Experimental (CONICET-FIBYME), Buenos Aires C1418ADN, Argentina
| | - Jacob I Sznajder
- Division of Pulmonary and Critical Care Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Olga Vagin
- Department of Physiology, David Geffen School of Medicine, UCLA, Los Angeles, CA 90095, USA Veterans Administration Greater Los Angeles Healthcare System, Los Angeles, CA 90095, USA
| | - Laura A Dada
- Division of Pulmonary and Critical Care Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
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4
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Patil PU, D'Ambrosio J, Inge LJ, Mason RW, Rajasekaran AK. Carcinoma cells induce lumen filling and EMT in epithelial cells through soluble E-cadherin-mediated activation of EGFR. J Cell Sci 2015; 128:4366-79. [PMID: 26483386 DOI: 10.1242/jcs.173518] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 10/13/2015] [Indexed: 12/31/2022] Open
Abstract
In epithelial cancers, carcinoma cells coexist with normal cells. Although it is known that the tumor microenvironment (TME) plays a pivotal role in cancer progression, it is not completely understood how the tumor influences adjacent normal epithelial cells. In this study, a three-dimensional co-culture system comprising non-transformed epithelial cells (MDCK) and transformed carcinoma cells (MSV-MDCK) was used to demonstrate that carcinoma cells sequentially induce preneoplastic lumen filling and epithelial-mesenchymal transition (EMT) in epithelial cysts. MMP-9 secreted by carcinoma cells cleaves cellular E-cadherin (encoded by CDH1) from epithelial cells to generate soluble E-cadherin (sE-cad), a pro-oncogenic protein. We show that sE-cad induces EGFR activation, resulting in lumen filling in MDCK cysts. Long-term sE-cad treatment induced EMT. sE-cad caused lumen filling by induction of the ERK signaling pathway and triggered EMT through the sustained activation of the AKT pathway. Although it is known that sE-cad induces MMP-9 release and consequent EGFR activation in tumor cells, our results, for the first time, demonstrate that carcinoma cells can induce sE-cad shedding in adjacent epithelial cells, which leads to EGFR activation and the eventual transdifferentiation of the normal epithelial cells.
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Affiliation(s)
- Pratima U Patil
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA Nemours Center for Childhood Cancer Research, Department of Biomedical Research, Alfred I. duPont Hospital for Children, Wilmington, DE 19803, USA
| | - Julia D'Ambrosio
- Nemours Center for Childhood Cancer Research, Department of Biomedical Research, Alfred I. duPont Hospital for Children, Wilmington, DE 19803, USA
| | - Landon J Inge
- Thoracic and Esophageal disease, Norton Thoracic Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ 85013, USA
| | - Robert W Mason
- Nemours Center for Childhood Cancer Research, Department of Biomedical Research, Alfred I. duPont Hospital for Children, Wilmington, DE 19803, USA
| | - Ayyappan K Rajasekaran
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA Therapy Architects, LLC, 2700, Silverside Road, Wilmington, DE 19810, USA
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Lee SJ, Litan A, Li Z, Graves B, Lindsey S, Barwe SP, Langhans SA. Na,K-ATPase β1-subunit is a target of sonic hedgehog signaling and enhances medulloblastoma tumorigenicity. Mol Cancer 2015; 14:159. [PMID: 26286140 PMCID: PMC4544806 DOI: 10.1186/s12943-015-0430-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Accepted: 08/11/2015] [Indexed: 02/06/2023] Open
Abstract
Background The Sonic hedgehog (Shh) signaling pathway plays an important role in cerebellar development, and mutations leading to hyperactive Shh signaling have been associated with certain forms of medulloblastoma, a common form of pediatric brain cancer. While the fundamentals of this pathway are known, the molecular targets contributing to Shh-mediated proliferation and transformation are still poorly understood. Na,K-ATPase is a ubiquitous enzyme that maintains intracellular ion homeostasis and functions as a signaling scaffold and a cell adhesion molecule. Changes in Na,K-ATPase function and subunit expression have been reported in several cancers and loss of the β1-subunit has been associated with a poorly differentiated phenotype in carcinoma but its role in medulloblastoma progression is not known. Methods Human medulloblastoma cell lines and primary cultures of cerebellar granule cell precursors (CGP) were used to determine whether Shh regulates Na,K-ATPase expression. Smo/Smo medulloblastoma were used to assess the Na,K-ATPase levels in vivo. Na,K-ATPase β1-subunit was knocked down in DAOY cells to test its role in medulloblastoma cell proliferation and tumorigenicity. Results Na,K-ATPase β1-subunit levels increased with differentiation in normal CGP cells. Activation of Shh signaling resulted in reduced β1-subunit mRNA and protein levels and was mimicked by overexpression of Gli1and Bmi1, both members of the Shh signaling cascade; overexpression of Bmi1 reduced β1-subunit promoter activity. In human medulloblastoma cells, low β1-subunit levels were associated with increased cell proliferation and in vivo tumorigenesis. Conclusions Na,K-ATPase β1-subunit is a target of the Shh signaling pathway and loss of β1-subunit expression may contribute to tumor development and progression not only in carcinoma but also in medulloblastoma, a tumor of neuronal origin.
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Affiliation(s)
- Seung Joon Lee
- Nemours/Alfred I. duPont Hospital for Children, Rockland Center I, 1701 Rockland Road, Wilmington, DE, 19803, USA
| | - Alisa Litan
- Nemours/Alfred I. duPont Hospital for Children, Rockland Center I, 1701 Rockland Road, Wilmington, DE, 19803, USA
| | - Zhiqin Li
- Nemours/Alfred I. duPont Hospital for Children, Rockland Center I, 1701 Rockland Road, Wilmington, DE, 19803, USA
| | - Bruce Graves
- Nemours/Alfred I. duPont Hospital for Children, Rockland Center I, 1701 Rockland Road, Wilmington, DE, 19803, USA
| | - Stephan Lindsey
- Nemours/Alfred I. duPont Hospital for Children, Rockland Center I, 1701 Rockland Road, Wilmington, DE, 19803, USA
| | - Sonali P Barwe
- Nemours/Alfred I. duPont Hospital for Children, Rockland Center I, 1701 Rockland Road, Wilmington, DE, 19803, USA
| | - Sigrid A Langhans
- Nemours/Alfred I. duPont Hospital for Children, Rockland Center I, 1701 Rockland Road, Wilmington, DE, 19803, USA.
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6
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Balasubramaniam SL, Gopalakrishnapillai A, Barwe SP. Ion dependence of Na-K-ATPase-mediated epithelial cell adhesion and migration. Am J Physiol Cell Physiol 2015; 309:C437-41. [PMID: 26157008 DOI: 10.1152/ajpcell.00140.2015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Sona Lakshme Balasubramaniam
- Nemours Center for Childhood Cancer Research, Alfred I. duPont Hospital for Children, Wilmington, Delaware; and Department of Biological Sciences, University of Delaware, Newark, Delaware
| | | | - Sonali P Barwe
- Nemours Center for Childhood Cancer Research, Alfred I. duPont Hospital for Children, Wilmington, Delaware; and Department of Biological Sciences, University of Delaware, Newark, Delaware
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7
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Regulation of cough by neuronal Na(+)-K(+) ATPases. Curr Opin Pharmacol 2015; 22:140-5. [PMID: 26048736 DOI: 10.1016/j.coph.2015.05.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 04/29/2015] [Accepted: 05/01/2015] [Indexed: 01/10/2023]
Abstract
The Na(+)-K(+) ATPases play an essential role in establishing the sodium gradients in excitable cells. Multiple isoforms of the sodium pumps have been identified, with tissue and cell specific expression patterns. Because the vagal afferent nerves regulating cough must be activated at sustained high frequencies of action potential patterning to achieve cough initiation thresholds, it is a certainty that sodium pump function is essential to maintaining cough reflex sensitivities in health and in disease. The mechanisms by which Na(+)-K(+) ATPases regulate bronchopulmonary vagal afferent nerve excitability are reviewed as are potential therapeutic strategies targeting the sodium pumps in cough.
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Huynh TP, Barwe SP, Lee SJ, McSpadden R, Franco OE, Hayward SW, Damoiseaux R, Grubbs SS, Petrelli NJ, Rajasekaran AK. Glucocorticoids suppress renal cell carcinoma progression by enhancing Na,K-ATPase beta-1 subunit expression. PLoS One 2015; 10:e0122442. [PMID: 25836370 PMCID: PMC4383530 DOI: 10.1371/journal.pone.0122442] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Accepted: 02/21/2015] [Indexed: 11/28/2022] Open
Abstract
Glucocorticoids are commonly used as palliative or chemotherapeutic clinical agents for treatment of a variety of cancers. Although steroid treatment is beneficial, the mechanisms by which steroids improve outcome in cancer patients are not well understood. Na,K-ATPase beta-subunit isoform 1 (NaK-β1) is a cell-cell adhesion molecule, and its expression is down-regulated in cancer cells undergoing epithelial-to mesenchymal-transition (EMT), a key event associated with cancer progression to metastatic disease. In this study, we performed high-throughput screening to identify small molecules that could up-regulate NaK-β1 expression in cancer cells. Compounds related to the glucocorticoids were identified as drug candidates enhancing NaK-β1 expression. Of these compounds, triamcinolone, dexamethasone, and fluorometholone were validated to increase NaK-β1 expression at the cell surface, enhance cell-cell adhesion, attenuate motility and invasiveness and induce mesenchymal to epithelial like transition of renal cell carcinoma (RCC) cells in vitro. Treatment of NaK-β1 knockdown cells with these drug candidates confirmed that these compounds mediate their effects through up-regulating NaK-β1. Furthermore, we demonstrated that these compounds attenuate tumor growth in subcutaneous RCC xenografts and reduce local invasiveness in orthotopically-implanted tumors. Our results strongly indicate that the addition of glucocorticoids in the treatment of RCC may improve outcome for RCC patients by augmenting NaK-β1 cell-cell adhesion function.
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MESH Headings
- Animals
- Carcinoma, Renal Cell/drug therapy
- Carcinoma, Renal Cell/enzymology
- Carcinoma, Renal Cell/pathology
- Cell Adhesion/drug effects
- Cell Line, Tumor
- Dexamethasone/pharmacology
- Disease Progression
- Fluorometholone/pharmacology
- Glucocorticoids/pharmacology
- HeLa Cells
- High-Throughput Screening Assays
- Humans
- Kidney Neoplasms/drug therapy
- Kidney Neoplasms/enzymology
- Kidney Neoplasms/pathology
- Male
- Mice
- Mice, Hairless
- Mice, SCID
- Neoplasm Invasiveness/prevention & control
- Promoter Regions, Genetic/drug effects
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Neoplasm/genetics
- RNA, Neoplasm/metabolism
- Sodium-Potassium-Exchanging ATPase/genetics
- Sodium-Potassium-Exchanging ATPase/metabolism
- Triamcinolone/pharmacology
- Up-Regulation/drug effects
- Xenograft Model Antitumor Assays
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Affiliation(s)
- Thu P. Huynh
- Molecular Biology Institute, University of California Los Angeles, Los Angeles, California, United States of America
- Nemours Center for Childhood Cancer Research, A. I. DuPont Hospital for Children, Wilmington, Delaware, United States of America
| | - Sonali P. Barwe
- Nemours Center for Childhood Cancer Research, A. I. DuPont Hospital for Children, Wilmington, Delaware, United States of America
| | - Seung J. Lee
- Nemours Center for Childhood Cancer Research, A. I. DuPont Hospital for Children, Wilmington, Delaware, United States of America
| | - Ryan McSpadden
- Nemours Center for Childhood Cancer Research, A. I. DuPont Hospital for Children, Wilmington, Delaware, United States of America
| | - Omar E. Franco
- Department of Urologic Surgery, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Simon W. Hayward
- Department of Urologic Surgery, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Robert Damoiseaux
- California NanoSystems Institute, University of California Los Angeles, Los Angeles, California, United States of America
| | - Stephen S. Grubbs
- Helen F. Graham Cancer Center, Christiana Care Health System, Newark, Delaware, United States of America
| | - Nicholas J. Petrelli
- Helen F. Graham Cancer Center, Christiana Care Health System, Newark, Delaware, United States of America
| | - Ayyappan K. Rajasekaran
- Helen F. Graham Cancer Center, Christiana Care Health System, Newark, Delaware, United States of America
- Department of Biological Sciences, University of Delaware, Newark, Delaware, United States of America
- Therapy Architects, 2700 Silverside Road, Wilmington, Delaware, United States of America
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Balasubramaniam SL, Gopalakrishnapillai A, Gangadharan V, Duncan RL, Barwe SP. Sodium-calcium exchanger 1 regulates epithelial cell migration via calcium-dependent extracellular signal-regulated kinase signaling. J Biol Chem 2015; 290:12463-73. [PMID: 25770213 DOI: 10.1074/jbc.m114.629519] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Indexed: 12/16/2022] Open
Abstract
Na(+)/Ca(2+) exchanger-1 (NCX1) is a major calcium extrusion mechanism in renal epithelial cells enabling the efflux of one Ca(2+) ion and the influx of three Na(+) ions. The gradient for this exchange activity is provided by Na,K-ATPase, a hetero-oligomer consisting of a catalytic α-subunit and a regulatory β-subunit (Na,K-β) that also functions as a motility and tumor suppressor. We showed earlier that mice with heart-specific ablation (KO) of Na,K-β had a specific reduction in NCX1 protein and were ouabain-insensitive. Here, we demonstrate that Na,K-β associates with NCX1 and regulates its localization to the cell surface. Madin-Darby canine kidney cells with Na,K-β knockdown have reduced NCX1 protein and function accompanied by 2.1-fold increase in free intracellular calcium and a corresponding increase in the rate of cell migration. Increased intracellular calcium up-regulated ERK1/2 via calmodulin-dependent activation of PI3K. Both myosin light chain kinase and Rho-associated kinase acted as mediators of ERK1/2-dependent migration. Restoring NCX1 expression in β-KD cells reduced migration rate and ERK1/2 activation, suggesting that NCX1 functions downstream of Na,K-β in regulating cell migration. In parallel, inhibition of NCX1 by KB-R7943 in Madin-Darby canine kidney cells, LLC-PK1, and human primary renal epithelial cells (HREpiC) increased ERK1/2 activation and cell migration. This increased migration was associated with high myosin light chain phosphorylation by PI3K/ERK-dependent mechanism in HREpiC cells. These data confirm the role of NCX1 activity in regulating renal epithelial cell migration.
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Affiliation(s)
- Sona Lakshme Balasubramaniam
- From the Nemours Center for Childhood Cancer Research, Alfred I. duPont Hospital for Children, Wilmington, Delaware 19803 and Department of Biological Sciences, University of Delaware, Newark, Delaware 19716
| | - Anilkumar Gopalakrishnapillai
- From the Nemours Center for Childhood Cancer Research, Alfred I. duPont Hospital for Children, Wilmington, Delaware 19803 and
| | - Vimal Gangadharan
- Department of Biological Sciences, University of Delaware, Newark, Delaware 19716
| | - Randall L Duncan
- Department of Biological Sciences, University of Delaware, Newark, Delaware 19716
| | - Sonali P Barwe
- From the Nemours Center for Childhood Cancer Research, Alfred I. duPont Hospital for Children, Wilmington, Delaware 19803 and Department of Biological Sciences, University of Delaware, Newark, Delaware 19716
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