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Brunetti V, Berra-Romani R, Conca F, Soda T, Biella GR, Gerbino A, Moccia F, Scarpellino G. Lysosomal TRPML1 triggers global Ca 2+ signals and nitric oxide release in human cerebrovascular endothelial cells. Front Physiol 2024; 15:1426783. [PMID: 38974517 PMCID: PMC11224436 DOI: 10.3389/fphys.2024.1426783] [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: 05/02/2024] [Accepted: 06/03/2024] [Indexed: 07/09/2024] Open
Abstract
Lysosomal Ca2+ signaling is emerging as a crucial regulator of endothelial Ca2+ dynamics. Ca2+ release from the acidic vesicles in response to extracellular stimulation is usually promoted via Two Pore Channels (TPCs) and is amplified by endoplasmic reticulum (ER)-embedded inositol-1,3,4-trisphosphate (InsP3) receptors and ryanodine receptors. Emerging evidence suggests that sub-cellular Ca2+ signals in vascular endothelial cells can also be generated by the Transient Receptor Potential Mucolipin 1 channel (TRPML1) channel, which controls vesicle trafficking, autophagy and gene expression. Herein, we adopted a multidisciplinary approach, including live cell imaging, pharmacological manipulation, and gene targeting, revealing that TRPML1 protein is expressed and triggers global Ca2+ signals in the human brain microvascular endothelial cell line, hCMEC/D3. The direct stimulation of TRPML1 with both the synthetic agonist, ML-SA1, and the endogenous ligand phosphatidylinositol 3,5-bisphosphate (PI(3,5)P2) induced a significant increase in [Ca2+]i, that was reduced by pharmacological blockade and genetic silencing of TRPML1. In addition, TRPML1-mediated lysosomal Ca2+ release was sustained both by lysosomal Ca2+ release and ER Ca2+- release through inositol-1,4,5-trisphophate receptors and store-operated Ca2+ entry. Notably, interfering with TRPML1-mediated lysosomal Ca2+ mobilization led to a decrease in the free ER Ca2+ concentration. Imaging of DAF-FM fluorescence revealed that TRPML1 stimulation could also induce a significant Ca2+-dependent increase in nitric oxide concentration. Finally, the pharmacological and genetic blockade of TRPML1 impaired ATP-induced intracellular Ca2+ release and NO production. These findings, therefore, shed novel light on the mechanisms whereby the lysosomal Ca2+ store can shape endothelial Ca2+ signaling and Ca2+-dependent functions in vascular endothelial cells.
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Affiliation(s)
- Valentina Brunetti
- Laboratory of General Physiology, Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, Pavia, Italy
| | - Roberto Berra-Romani
- Department of Biomedicine, School of Medicine, Benemérita Universidad Autónoma de Puebla, Puebla, Mexico
| | - Filippo Conca
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
- Veneto Institute of Molecular Medicine, Foundation for Advanced Biomedical Research, Padova, Italy
| | - Teresa Soda
- Department of Health Sciences, University of Magna Graecia, Catanzaro, Italy
| | - Gerardo Rosario Biella
- Laboratory of General Physiology, Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, Pavia, Italy
| | - Andrea Gerbino
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari “Aldo Moro”, Bari, Italy
| | - Francesco Moccia
- Department of Medicine and Health Sciences “V. Tiberio”, University of Molise, Campobasso, Italy
| | - Giorgia Scarpellino
- Laboratory of General Physiology, Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, Pavia, Italy
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Moccia F, Brunetti V, Soda T, Berra-Romani R, Scarpellino G. Cracking the Endothelial Calcium (Ca 2+) Code: A Matter of Timing and Spacing. Int J Mol Sci 2023; 24:16765. [PMID: 38069089 PMCID: PMC10706333 DOI: 10.3390/ijms242316765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 11/16/2023] [Accepted: 11/24/2023] [Indexed: 12/18/2023] Open
Abstract
A monolayer of endothelial cells lines the innermost surface of all blood vessels, thereby coming into close contact with every region of the body and perceiving signals deriving from both the bloodstream and parenchymal tissues. An increase in intracellular Ca2+ concentration ([Ca2+]i) is the main mechanism whereby vascular endothelial cells integrate the information conveyed by local and circulating cues. Herein, we describe the dynamics and spatial distribution of endothelial Ca2+ signals to understand how an array of spatially restricted (at both the subcellular and cellular levels) Ca2+ signals is exploited by the vascular intima to fulfill this complex task. We then illustrate how local endothelial Ca2+ signals affect the most appropriate vascular function and are integrated to transmit this information to more distant sites to maintain cardiovascular homeostasis. Vasorelaxation and sprouting angiogenesis were selected as an example of functions that are finely tuned by the variable spatio-temporal profile endothelial Ca2+ signals. We further highlighted how distinct Ca2+ signatures regulate the different phases of vasculogenesis, i.e., proliferation and migration, in circulating endothelial precursors.
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Affiliation(s)
- Francesco Moccia
- Laboratory of General Physiology, Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, 27100 Pavia, Italy; (V.B.); (G.S.)
| | - Valentina Brunetti
- Laboratory of General Physiology, Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, 27100 Pavia, Italy; (V.B.); (G.S.)
| | - Teresa Soda
- Department of Health Sciences, University of Magna Graecia, 88100 Catanzaro, Italy;
| | - Roberto Berra-Romani
- Department of Biomedicine, School of Medicine, Benemérita Universidad Autónoma de Puebla, Puebla 72410, Mexico;
| | - Giorgia Scarpellino
- Laboratory of General Physiology, Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, 27100 Pavia, Italy; (V.B.); (G.S.)
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3
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Yao Y, Borkar NA, Zheng M, Wang S, Pabelick CM, Vogel ER, Prakash YS. Interactions between calcium regulatory pathways and mechanosensitive channels in airways. Expert Rev Respir Med 2023; 17:903-917. [PMID: 37905552 PMCID: PMC10872943 DOI: 10.1080/17476348.2023.2276732] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 10/25/2023] [Indexed: 11/02/2023]
Abstract
INTRODUCTION Asthma is a chronic lung disease influenced by environmental and inflammatory triggers and involving complex signaling pathways across resident airway cells such as epithelium, airway smooth muscle, fibroblasts, and immune cells. While our understanding of asthma pathophysiology is continually progressing, there is a growing realization that cellular microdomains play critical roles in mediating signaling relevant to asthma in the context of contractility and remodeling. Mechanosensitive pathways are increasingly recognized as important to microdomain signaling, with Piezo and transient receptor protein (TRP) channels at the plasma membrane considered important for converting mechanical stimuli into cellular behavior. Given their ion channel properties, particularly Ca2+ conduction, a question becomes whether and how mechanosensitive channels contribute to Ca2+ microdomains in airway cells relevant to asthma. AREAS COVERED Mechanosensitive TRP and Piezo channels regulate key Ca2+ regulatory proteins such as store operated calcium entry (SOCE) involving STIM and Orai channels, and sarcoendoplasmic (SR) mechanisms such as IP3 receptor channels (IP3Rs), and SR Ca2+ ATPase (SERCA) that are important in asthma pathophysiology including airway hyperreactivity and remodeling. EXPERT OPINION Physical and/or functional interactions between Ca2+ regulatory proteins and mechanosensitive channels such as TRP and Piezo can toward understanding asthma pathophysiology and identifying novel therapeutic approaches.
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Affiliation(s)
- Yang Yao
- Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Xi’an Medical University, Xi’an, Shaanxi, China
- Department of Anesthesiology, Mayo Clinic, Rochester, MN, USA
| | - Niyati A Borkar
- Department of Anesthesiology, Mayo Clinic, Rochester, MN, USA
| | - Mengning Zheng
- Department of Anesthesiology, Mayo Clinic, Rochester, MN, USA
- Department of Respiratory and Critical Care Medicine, Guizhou Province People’s Hospital, Guiyang, Guizhou, China
| | - Shengyu Wang
- Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Xi’an Medical University, Xi’an, Shaanxi, China
| | - Christina M Pabelick
- Department of Anesthesiology, Mayo Clinic, Rochester, MN, USA
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
| | - Elizabeth R Vogel
- Department of Anesthesiology, Mayo Clinic, Rochester, MN, USA
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
| | - YS Prakash
- Department of Anesthesiology, Mayo Clinic, Rochester, MN, USA
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
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4
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Li Z, Liu J, Ballard K, Liang C, Wang C. Low-dose albumin-coated gold nanorods induce intercellular gaps on vascular endothelium by causing the contraction of cytoskeletal actin. J Colloid Interface Sci 2023; 649:844-854. [PMID: 37390532 DOI: 10.1016/j.jcis.2023.06.154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 06/17/2023] [Accepted: 06/22/2023] [Indexed: 07/02/2023]
Abstract
Cytotoxicity of nanoparticles, typically evaluated by biochemical-based assays, often overlook the cellular biophysical properties such as cell morphology and cytoskeletal actin, which could serve as more sensitive indicators for cytotoxicity. Here, we demonstrate that low-dose albumin-coated gold nanorods (HSA@AuNRs), although being considered noncytotoxic in multiple biochemical assays, can induce intercellular gaps and enhance the paracellular permeability between human aortic endothelial cells (HAECs). The formation of intercellular gaps can be attributed to the changed cell morphology and cytoskeletal actin structures, as validated at the monolayer and single cell levels using fluorescence staining, atomic force microscopy, and super-resolution imaging. Molecular mechanistic study shows the caveolae-mediated endocytosis of HSA@AuNRs induces the calcium influx and activates actomyosin contraction in HAECs. Considering the important roles of endothelial integrity/dysfunction in various physiological/pathological conditions, this work suggests a potential adverse effect of albumin-coated gold nanorods on the cardiovascular system. On the other hand, this work also offers a feasible way to modulate the endothelial permeability, thus promoting drug and nanoparticle delivery across the endothelium.
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Affiliation(s)
- Zhengqiang Li
- Nanoscience and Biomedical Engineering, South Dakota School of Mines and Technology, 501 E St Joseph Street, Rapid City, SD 57701, USA; BioSystems Networks & Translational Research (BioSNTR), 501 E St Joseph Street, Rapid City, SD 57701, USA
| | - Jinyuan Liu
- Nanoscience and Biomedical Engineering, South Dakota School of Mines and Technology, 501 E St Joseph Street, Rapid City, SD 57701, USA; BioSystems Networks & Translational Research (BioSNTR), 501 E St Joseph Street, Rapid City, SD 57701, USA
| | - Katherine Ballard
- Nanoscience and Biomedical Engineering, South Dakota School of Mines and Technology, 501 E St Joseph Street, Rapid City, SD 57701, USA; BioSystems Networks & Translational Research (BioSNTR), 501 E St Joseph Street, Rapid City, SD 57701, USA
| | - Chao Liang
- Department of Anesthesiology, Zhongshan Hospital (Xiamen) Fudan University, Xiamen 361015, China; Department of Anesthesiology, Zhongshan Hospital, Fudan University, Shanghai 200032, China.
| | - Congzhou Wang
- Nanoscience and Biomedical Engineering, South Dakota School of Mines and Technology, 501 E St Joseph Street, Rapid City, SD 57701, USA; BioSystems Networks & Translational Research (BioSNTR), 501 E St Joseph Street, Rapid City, SD 57701, USA.
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Mathew R, Iacobas S, Huang J, Iacobas DA. Metabolic Deregulation in Pulmonary Hypertension. Curr Issues Mol Biol 2023; 45:4850-4874. [PMID: 37367058 DOI: 10.3390/cimb45060309] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 05/26/2023] [Accepted: 05/31/2023] [Indexed: 06/28/2023] Open
Abstract
The high morbidity and mortality rate of pulmonary arterial hypertension (PAH) is partially explained by metabolic deregulation. The present study complements our previous publication in "Genes" by identifying significant increases of the glucose transporter solute carrier family 2 (Slc2a1), beta nerve growth factor (Ngf), and nuclear factor erythroid-derived 2-like 2 (Nfe2l2) in three standard PAH rat models. PAH was induced by subjecting the animals to hypoxia (HO), or by injecting with monocrotaline in either normal (CM) or hypoxic (HM) atmospheric conditions. The Western blot and double immunofluorescent experiments were complemented with novel analyses of previously published transcriptomic datasets of the animal lungs from the perspective of the Genomic Fabric Paradigm. We found substantial remodeling of the citrate cycle, pyruvate metabolism, glycolysis/gluconeogenesis, and fructose and mannose pathways. According to the transcriptomic distance, glycolysis/gluconeogenesis was the most affected functional pathway in all three PAH models. PAH decoupled the coordinated expression of many metabolic genes, and replaced phosphomannomutase 2 (Pmm2) with phosphomannomutase 1 (Pmm1) in the center of the fructose and mannose metabolism. We also found significant regulation of key genes involved in PAH channelopathies. In conclusion, our data show that metabolic dysregulation is a major PAH pathogenic factor.
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Affiliation(s)
- Rajamma Mathew
- Department of Pediatrics, New York Medical College, Valhalla, NY 10595, USA
- Department of Physiology, New York Medical College, Valhalla, NY 10595, USA
| | - Sanda Iacobas
- Department of Pathology, New York Medical College, Valhalla, NY 10595, USA
| | - Jing Huang
- Department of Pathology and Laboratory Medicine, Rutgers University Biomedical and Health Sciences, New Brunswick, NJ 08901, USA
| | - Dumitru Andrei Iacobas
- Personalized Genomics Laboratory, Texas Undergraduate Medical Academy, Prairie View A&M University, Prairie View, TX 77446, USA
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Hong SG, Ashby JW, Kennelly JP, Wu M, Chattopadhyay E, Foreman R, Tontonoz P, Turowski P, Gallagher-Jones M, Mack JJ. Polarized Mechanosensitive Signaling Domains Protect Arterial Endothelial Cells Against Inflammation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.26.542500. [PMID: 37292837 PMCID: PMC10246006 DOI: 10.1101/2023.05.26.542500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Endothelial cells (ECs) in the descending aorta are exposed to high laminar shear stress, which supports an anti-inflammatory phenotype that protects them from atherosclerosis. High laminar shear stress also supports flow-aligned cell elongation and front-rear polarity, but whether this is required for athero-protective signaling is unclear. Here, we show that Caveolin-1-rich microdomains become polarized at the downstream end of ECs exposed to continuous high laminar flow. These microdomains are characterized by higher membrane rigidity, filamentous actin (F-actin) and lipid accumulation. Transient receptor potential vanilloid-type 4 (Trpv4) ion channels, while ubiquitously expressed, mediate localized Ca 2+ entry at these microdomains where they physically interact with clustered Caveolin-1. The resultant focal bursts in Ca 2+ activate the anti-inflammatory factor endothelial nitric oxide synthase (eNOS) within the confines of these domains. Importantly, we find that signaling at these domains requires both cell body elongation and sustained flow. Finally, Trpv4 signaling at these domains is necessary and sufficient to suppress inflammatory gene expression. Our work reveals a novel polarized mechanosensitive signaling hub that induces an anti-inflammatory response in arterial ECs exposed to high laminar shear stress.
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7
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The Molecular Heterogeneity of Store-Operated Ca 2+ Entry in Vascular Endothelial Cells: The Different roles of Orai1 and TRPC1/TRPC4 Channels in the Transition from Ca 2+-Selective to Non-Selective Cation Currents. Int J Mol Sci 2023; 24:ijms24043259. [PMID: 36834672 PMCID: PMC9967124 DOI: 10.3390/ijms24043259] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 01/31/2023] [Accepted: 02/03/2023] [Indexed: 02/11/2023] Open
Abstract
Store-operated Ca2+ entry (SOCE) is activated in response to the inositol-1,4,5-trisphosphate (InsP3)-dependent depletion of the endoplasmic reticulum (ER) Ca2+ store and represents a ubiquitous mode of Ca2+ influx. In vascular endothelial cells, SOCE regulates a plethora of functions that maintain cardiovascular homeostasis, such as angiogenesis, vascular tone, vascular permeability, platelet aggregation, and monocyte adhesion. The molecular mechanisms responsible for SOCE activation in vascular endothelial cells have engendered a long-lasting controversy. Traditionally, it has been assumed that the endothelial SOCE is mediated by two distinct ion channel signalplexes, i.e., STIM1/Orai1 and STIM1/Transient Receptor Potential Canonical 1(TRPC1)/TRPC4. However, recent evidence has shown that Orai1 can assemble with TRPC1 and TRPC4 to form a non-selective cation channel with intermediate electrophysiological features. Herein, we aim at bringing order to the distinct mechanisms that mediate endothelial SOCE in the vascular tree from multiple species (e.g., human, mouse, rat, and bovine). We propose that three distinct currents can mediate SOCE in vascular endothelial cells: (1) the Ca2+-selective Ca2+-release activated Ca2+ current (ICRAC), which is mediated by STIM1 and Orai1; (2) the store-operated non-selective current (ISOC), which is mediated by STIM1, TRPC1, and TRPC4; and (3) the moderately Ca2+-selective, ICRAC-like current, which is mediated by STIM1, TRPC1, TRPC4, and Orai1.
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8
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Pacheco J, Bohórquez-Hernández A, Méndez-Acevedo KM, Sampieri A, Vaca L. Roles of Cholesterol and PtdIns(4,5)P 2 in the Regulation of STIM1-Orai1 Channel Function. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1422:305-326. [PMID: 36988886 DOI: 10.1007/978-3-031-21547-6_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
Abstract
Calcium is one of the most prominent second messengers. It is involved in a wide range of functions at the single-cell level but also in modulating regulatory mechanisms in the entire organism. One process mediating calcium signaling involves hydrolysis of phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P2) by the phospholipase-C (PLC). Thus, calcium and PtdIns(4,5)P2 are intimately intertwined two second-messenger cascades that often depend on each other. Another relevant lipid associated with calcium signaling is cholesterol. Both PtdIns(4,5)P2 and cholesterol play key roles in the formation and maintenance of specialized signaling nanodomains known as lipid rafts. Lipid rafts are particularly important in calcium signaling by concentrating and localizing calcium channels such as the Orai1 channel. Depletion of internal calcium stores is initiated by the production of inositol-1,4,5-trisphosphate (IP3). Calcium depletion from the ER induces the oligomerization of STIM1, which binds Orai1 and initiates calcium influx into the cell. In the present review, we analyzed the complex interactions between cholesterol, PtdIns(4,5)P2, and the complex formed by the Orai1 channel and the signaling molecule STIM1. We explore some of the complex mechanisms governing calcium homeostasis and phospholipid metabolism, as well as the interaction between these two apparently independent signaling cascades.
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Affiliation(s)
- Jonathan Pacheco
- Department of Pharmacology and Chemical Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | | | - Kevin M Méndez-Acevedo
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
- ZHK, German Center for Cardiovascular Research, Partner Site, Berlin, Germany
| | - Alicia Sampieri
- Departamento de Biología Celular y del Desarrollo, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, México City, México
| | - Luis Vaca
- Departamento de Biología Celular y del Desarrollo, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, México City, México.
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Tiffner A, Hopl V, Derler I. CRAC and SK Channels: Their Molecular Mechanisms Associated with Cancer Cell Development. Cancers (Basel) 2022; 15:cancers15010101. [PMID: 36612099 PMCID: PMC9817886 DOI: 10.3390/cancers15010101] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 12/16/2022] [Accepted: 12/19/2022] [Indexed: 12/28/2022] Open
Abstract
Cancer represents a major health burden worldwide. Several molecular targets have been discovered alongside treatments with positive clinical outcomes. However, the reoccurrence of cancer due to therapy resistance remains the primary cause of mortality. Endeavors in pinpointing new markers as molecular targets in cancer therapy are highly desired. The significance of the co-regulation of Ca2+-permeating and Ca2+-regulated ion channels in cancer cell development, proliferation, and migration make them promising molecular targets in cancer therapy. In particular, the co-regulation of the Orai1 and SK3 channels has been well-studied in breast and colon cancer cells, where it finally leads to an invasion-metastasis cascade. Nevertheless, many questions remain unanswered, such as which key molecular components determine and regulate their interplay. To provide a solid foundation for a better understanding of this ion channel co-regulation in cancer, we first shed light on the physiological role of Ca2+ and how this ion is linked to carcinogenesis. Then, we highlight the structure/function relationship of Orai1 and SK3, both individually and in concert, their role in the development of different types of cancer, and aspects that are not yet known in this context.
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Rodrigues MA, Gomes DA, Fiorotto R, Guerra MT, Weerachayaphorn J, Bo T, Sessa WC, Strazzabosco M, Nathanson MH. Molecular determinants of peri-apical targeting of inositol 1,4,5-trisphosphate receptor type 3 in cholangiocytes. Hepatol Commun 2022; 6:2748-2764. [PMID: 35852334 PMCID: PMC9512452 DOI: 10.1002/hep4.2042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Revised: 06/03/2022] [Accepted: 06/20/2022] [Indexed: 11/19/2022] Open
Abstract
Fluid and bicarbonate secretion is a principal function of cholangiocytes, and impaired secretion results in cholestasis. Cholangiocyte secretion depends on peri-apical expression of the type 3 inositol trisphosphate receptor (ITPR3), and loss of this intracellular Ca2+ release channel is a final common event in most cholangiopathies. Here we investigated the mechanism by which ITPR3 localizes to the apical region to regulate secretion. Isolated bile duct units, primary mouse cholangiocytes, and polarized Madin-Darby canine kidney (MDCK) cells were examined using a combination of biochemical and fluorescence microscopy techniques to investigate the mechanism of ITPR3 targeting to the apical region. Apical localization of ITPR3 depended on the presence of intact lipid rafts as well as interactions with both caveolin 1 (CAV1) and myosin heavy chain 9 (MYH9). Chemical disruption of lipid rafts or knockdown of CAV1 or MYH9 redistributed ITPR3 away from the apical region. MYH9 interacted with the five c-terminal amino acids of the ITPR3 peptide. Disruption of lipid rafts impaired Ca2+ signaling, and absence of CAV1 impaired both Ca2+ signaling and fluid secretion. Conclusion: A cooperative mechanism involving MYH9, CAV1, and apical lipid rafts localize ITPR3 to the apical region to regulate Ca2+ signaling and secretion in cholangiocytes.
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Affiliation(s)
- Michele A. Rodrigues
- Section of Digestive Diseases, Internal MedicineYale UniversityNew HavenConnecticutUSA
- Department of Biochemistry and ImmunologyFederal University of Minas Gerais (UFMG)Belo HorizonteMGBrazil
| | - Dawidson A. Gomes
- Section of Digestive Diseases, Internal MedicineYale UniversityNew HavenConnecticutUSA
- Department of Biochemistry and ImmunologyFederal University of Minas Gerais (UFMG)Belo HorizonteMGBrazil
| | - Romina Fiorotto
- Section of Digestive Diseases, Internal MedicineYale UniversityNew HavenConnecticutUSA
| | - Mateus T. Guerra
- Section of Digestive Diseases, Internal MedicineYale UniversityNew HavenConnecticutUSA
| | | | - Tao Bo
- Department of Pharmacology and Program in Vascular Cell Signaling and TherapeuticsYale University School of MedicineNew HavenConnecticutUSA
| | - William C. Sessa
- Department of Pharmacology and Program in Vascular Cell Signaling and TherapeuticsYale University School of MedicineNew HavenConnecticutUSA
| | - Mario Strazzabosco
- Section of Digestive Diseases, Internal MedicineYale UniversityNew HavenConnecticutUSA
| | - Michael H. Nathanson
- Section of Digestive Diseases, Internal MedicineYale UniversityNew HavenConnecticutUSA
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Lipid Dyshomeostasis and Inherited Cerebellar Ataxia. Mol Neurobiol 2022; 59:3800-3828. [PMID: 35420383 PMCID: PMC9148275 DOI: 10.1007/s12035-022-02826-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 04/01/2022] [Indexed: 12/04/2022]
Abstract
Cerebellar ataxia is a form of ataxia that originates from dysfunction of the cerebellum, but may involve additional neurological tissues. Its clinical symptoms are mainly characterized by the absence of voluntary muscle coordination and loss of control of movement with varying manifestations due to differences in severity, in the site of cerebellar damage and in the involvement of extracerebellar tissues. Cerebellar ataxia may be sporadic, acquired, and hereditary. Hereditary ataxia accounts for the majority of cases. Hereditary ataxia has been tentatively divided into several subtypes by scientists in the field, and nearly all of them remain incurable. This is mainly because the detailed mechanisms of these cerebellar disorders are incompletely understood. To precisely diagnose and treat these diseases, studies on their molecular mechanisms have been conducted extensively in the past. Accumulating evidence has demonstrated that some common pathogenic mechanisms exist within each subtype of inherited ataxia. However, no reports have indicated whether there is a common mechanism among the different subtypes of inherited cerebellar ataxia. In this review, we summarize the available references and databases on neurological disorders characterized by cerebellar ataxia and show that a subset of genes involved in lipid homeostasis form a new group that may cause ataxic disorders through a common mechanism. This common signaling pathway can provide a valuable reference for future diagnosis and treatment of ataxic disorders.
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Maltan L, Andova AM, Derler I. The Role of Lipids in CRAC Channel Function. Biomolecules 2022; 12:biom12030352. [PMID: 35327543 PMCID: PMC8944985 DOI: 10.3390/biom12030352] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 02/12/2022] [Accepted: 02/20/2022] [Indexed: 11/28/2022] Open
Abstract
The composition and dynamics of the lipid membrane define the physical properties of the bilayer and consequently affect the function of the incorporated membrane transporters, which also applies for the prominent Ca2+ release-activated Ca2+ ion channel (CRAC). This channel is activated by receptor-induced Ca2+ store depletion of the endoplasmic reticulum (ER) and consists of two transmembrane proteins, STIM1 and Orai1. STIM1 is anchored in the ER membrane and senses changes in the ER luminal Ca2+ concentration. Orai1 is the Ca2+-selective, pore-forming CRAC channel component located in the plasma membrane (PM). Ca2+ store-depletion of the ER triggers activation of STIM1 proteins, which subsequently leads to a conformational change and oligomerization of STIM1 and its coupling to as well as activation of Orai1 channels at the ER-PM contact sites. Although STIM1 and Orai1 are sufficient for CRAC channel activation, their efficient activation and deactivation is fine-tuned by a variety of lipids and lipid- and/or ER-PM junction-dependent accessory proteins. The underlying mechanisms for lipid-mediated CRAC channel modulation as well as the still open questions, are presented in this review.
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13
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Li C, Huang J, Tang H, Liu B, Zhou X. Revealing Cavin-2 Gene Function in Lung Based on Multi-Omics Data Analysis Method. Front Cell Dev Biol 2022; 9:827108. [PMID: 35174175 PMCID: PMC8841408 DOI: 10.3389/fcell.2021.827108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 12/15/2021] [Indexed: 11/23/2022] Open
Abstract
Research points out that it is particularly important to comprehensively evaluate immune microenvironmental indicators and gene mutation characteristics to select the best treatment plan. Therefore, exploring the relevant genes of pulmonary injury is an important basis for the improvement of survival. In recent years, with the massive production of omics data, a large number of computational methods have been applied in the field of biomedicine. Most of these computational methods are devel-oped for a certain type of diseases or whole diseases. Algorithms that specifically identify genes associated with pulmonary injury have not yet been developed. To fill this gap, we developed a novel method, named AdaRVM, to identify pulmonary injury-related genes in large scale. AdaRVM is the fusion of Adaboost and Relevance Vector Machine (RVM) to achieve fast and high-precision pattern recognition of pulmonary injury genetic mechanism. AdaRVM found that Cavin-2 gene has strong potential to be related to pulmonary injury. As we known, the formation and function of Caveolae are mediated by two family proteins: Caveolin and Cavin. Many studies have explored the role of Caveolin proteins, but people still knew little about Cavin family members. To verify our method and reveal the functions of cavin-2, we integrated six genome-wide association studies (GWAS) data related to lung function traits, four expression Quantitative Trait Loci (eQTL) data, and one methylation Quantitative Trait Loci (mQTL) data by Summary data level Mendelian Randomization (SMR). We found strong relationship between cavin-2 and canonical signaling pathways ERK1/2, AKT, and STAT3 which are all known to be related to lung injury.
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Affiliation(s)
- Changsheng Li
- Department of Thoracic Surgery, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Jingyu Huang
- Department of Thoracic Surgery, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Hexiao Tang
- Department of Thoracic Surgery, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Bing Liu
- Department of Pulmonary and Critical Care Medicine, Zhongnan Hospital of Wuhan University, Wuhan, China
- Wuhan Research Center for Infectious Diseases and Cancer, Chinese Academy of Medical Sciences, Wuhan, China
| | - Xuefeng Zhou
- Department of Thoracic Surgery, Zhongnan Hospital of Wuhan University, Wuhan, China
- *Correspondence: Xuefeng Zhou,
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14
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Wang S, Ichinomiya T, Terada Y, Wang D, Patel HH, Head BP. Synapsin-Promoted Caveolin-1 Overexpression Maintains Mitochondrial Morphology and Function in PSAPP Alzheimer's Disease Mice. Cells 2021; 10:2487. [PMID: 34572135 PMCID: PMC8467690 DOI: 10.3390/cells10092487] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Revised: 09/15/2021] [Accepted: 09/17/2021] [Indexed: 02/03/2023] Open
Abstract
Mitochondrial dysfunction plays a pivotal role in the Alzheimer's Disease (AD) pathology. Disrupted mitochondrial dynamics (i.e., fusion/fission balance), which are essential for normal mitochondria structure and function, are documented in AD. Caveolin-1 (Cav-1), a membrane/lipid raft (MLR) scaffolding protein regulates metabolic pathways in several different cell types such as hepatocytes and cancer cells. Previously, we have shown decreased expression of Cav-1 in the hippocampus of 9-month (m) old PSAPP mice, while hippocampal overexpression of neuron-targeted Cav-1 using the synapsin promoter (i.e., SynCav1) preserved cognitive function, neuronal morphology, and synaptic ultrastructure in 9 and 12 m PSAPP mice. Considering the central role of energy production in maintaining normal neuronal and synaptic function and survival, the present study reveals that PSAPP mice exhibit disrupted mitochondrial distribution, morphometry, and respiration. In contrast, SynCav1 mitigates mitochondrial damage and loss and enhances mitochondrial respiration. Furthermore, by examining mitochondrial dynamics, we found that PSAPP mice showed a significant increase in the phosphorylation of mitochondrial dynamin-related GTPase protein (DRP1), resulting in excessive mitochondria fragmentation and dysfunction. In contrast, hippocampal delivery of SynCav1 significantly decreased p-DRP1 and augmented the level of the mitochondrial fusion protein, mitofusin1 (Mfn1) in PSAPP mice, a molecular event, which may mechanistically explain for the preserved balance of mitochondria fission/fusion and metabolic resilience in 12 m PSAPP-SynCav1 mice. Our data demonstrate the critical role for Cav-1 in maintaining normal mitochondrial morphology and function through affecting mitochondrial dynamics and explain a molecular and cellular mechanism underlying the previously reported neuroprotective and cognitive preservation induced by SynCav1 in PSAPP mouse model of AD.
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Affiliation(s)
- Shanshan Wang
- Veterans Affairs San Diego Healthcare System, 3350 La Jolla Village Drive, San Diego, CA 92161, USA; (S.W.); (T.I.); (Y.T.); (D.W.)
- Department of Anesthesia, University of California San Diego, San Diego, CA 92093, USA
| | - Taiga Ichinomiya
- Veterans Affairs San Diego Healthcare System, 3350 La Jolla Village Drive, San Diego, CA 92161, USA; (S.W.); (T.I.); (Y.T.); (D.W.)
- Department of Anesthesia, University of California San Diego, San Diego, CA 92093, USA
- Department of Anesthesiology and Intensive Care Medicine, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 8528501, Japan
| | - Yuki Terada
- Veterans Affairs San Diego Healthcare System, 3350 La Jolla Village Drive, San Diego, CA 92161, USA; (S.W.); (T.I.); (Y.T.); (D.W.)
- Department of Anesthesia, University of California San Diego, San Diego, CA 92093, USA
- Department of Anesthesiology, Nara Medical University, Kashihara 6348521, Japan
| | - Dongsheng Wang
- Veterans Affairs San Diego Healthcare System, 3350 La Jolla Village Drive, San Diego, CA 92161, USA; (S.W.); (T.I.); (Y.T.); (D.W.)
- Department of Anesthesia, University of California San Diego, San Diego, CA 92093, USA
| | - Hemal H. Patel
- Veterans Affairs San Diego Healthcare System, 3350 La Jolla Village Drive, San Diego, CA 92161, USA; (S.W.); (T.I.); (Y.T.); (D.W.)
- Department of Anesthesia, University of California San Diego, San Diego, CA 92093, USA
| | - Brian P. Head
- Veterans Affairs San Diego Healthcare System, 3350 La Jolla Village Drive, San Diego, CA 92161, USA; (S.W.); (T.I.); (Y.T.); (D.W.)
- Department of Anesthesia, University of California San Diego, San Diego, CA 92093, USA
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15
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Ion channels as convergence points in the pathology of pulmonary arterial hypertension. Biochem Soc Trans 2021; 49:1855-1865. [PMID: 34346486 PMCID: PMC8421048 DOI: 10.1042/bst20210538] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 07/15/2021] [Accepted: 07/16/2021] [Indexed: 12/17/2022]
Abstract
Pulmonary arterial hypertension (PAH) is a fatal disease of the cardiopulmonary system that lacks curative treatments. The main pathological event in PAH is elevated vascular resistance in the pulmonary circulation, caused by abnormal vasoconstriction and vascular remodelling. Ion channels are key determinants of vascular smooth muscle tone and homeostasis, and four PAH channelopathies (KCNK3, ABCC8, KCNA5, TRPC6) have been identified so far. However, the contribution of ion channels in other forms of PAH, which account for the majority of PAH patients, has been less well characterised. Here we reason that a variety of triggers of PAH (e.g. BMPR2 mutations, hypoxia, anorectic drugs) that impact channel function may contribute to the onset of the disease. We review the molecular mechanisms by which these ‘extrinsic’ factors converge on ion channels and provoke their dysregulation to promote the development of PAH. Ion channels of the pulmonary vasculature are therefore promising therapeutic targets because of the modulation they provide to both vasomotor tone and proliferation of arterial smooth muscle cells.
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16
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Crul T, Maléth J. Endoplasmic Reticulum-Plasma Membrane Contact Sites as an Organizing Principle for Compartmentalized Calcium and cAMP Signaling. Int J Mol Sci 2021; 22:4703. [PMID: 33946838 PMCID: PMC8124356 DOI: 10.3390/ijms22094703] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 04/20/2021] [Accepted: 04/27/2021] [Indexed: 01/14/2023] Open
Abstract
In eukaryotic cells, ultimate specificity in activation and action-for example, by means of second messengers-of the myriad of signaling cascades is primordial. In fact, versatile and ubiquitous second messengers, such as calcium (Ca2+) and cyclic adenosine monophosphate (cAMP), regulate multiple-sometimes opposite-cellular functions in a specific spatiotemporal manner. Cells achieve this through segregation of the initiators and modulators to specific plasma membrane (PM) subdomains, such as lipid rafts and caveolae, as well as by dynamic close contacts between the endoplasmic reticulum (ER) membrane and other intracellular organelles, including the PM. Especially, these membrane contact sites (MCSs) are currently receiving a lot of attention as their large influence on cell signaling regulation and cell physiology is increasingly appreciated. Depletion of ER Ca2+ stores activates ER membrane STIM proteins, which activate PM-residing Orai and TRPC Ca2+ channels at ER-PM contact sites. Within the MCS, Ca2+ fluxes relay to cAMP signaling through highly interconnected networks. However, the precise mechanisms of MCS formation and the influence of their dynamic lipid environment on their functional maintenance are not completely understood. The current review aims to provide an overview of our current understanding and to identify open questions of the field.
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Affiliation(s)
- Tim Crul
- First Department of Medicine, University of Szeged, H6720 Szeged, Hungary
- HAS-USZ Momentum Epithelial Cell Signaling and Secretion Research Group, University of Szeged, H6720 Szeged, Hungary
- HCEMM-SZTE Molecular Gastroenterology Research Group, University of Szeged, H6720 Szeged, Hungary
| | - József Maléth
- First Department of Medicine, University of Szeged, H6720 Szeged, Hungary
- HAS-USZ Momentum Epithelial Cell Signaling and Secretion Research Group, University of Szeged, H6720 Szeged, Hungary
- HCEMM-SZTE Molecular Gastroenterology Research Group, University of Szeged, H6720 Szeged, Hungary
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17
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TRPC channel-derived calcium fluxes differentially regulate ATP and flow-induced activation of eNOS. Nitric Oxide 2021; 111-112:1-13. [PMID: 33813098 DOI: 10.1016/j.niox.2021.03.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Accepted: 03/27/2021] [Indexed: 12/28/2022]
Abstract
Endothelial dysfunction, characterised by impaired nitric oxide (NO) bioavailability, arises in response to a variety of cardiovascular risk factors and precedes atherosclerosis. NO is produced by tight regulation of endothelial nitric oxide synthase (eNOS) activity in response to vasodilatory stimuli. This regulation of eNOS is mediated in part by store-operated calcium entry (SOCE). We hypothesized that both ATP- and flow-induced eNOS activation are regulated by SOCE derived from Orai1 channels and members of the transient receptor potential canonical (TRPC) channel family. Bovine aortic endothelial cells (BAECs) were pre-treated with pharmacological inhibitors of TRPC channels and Orai1 to examine their effect on calcium signaling and eNOS activation in response to flow and ATP. The peak and sustained ATP-induced calcium signal and the resulting eNOS activation were attenuated by inhibition of TRPC3, which we found to be store operated. TRPC4 blockade reduced the transient peak in calcium concentration following ATP stimulation, but did not significantly reduce eNOS activity. Simultaneous TRPC3 & 4 inhibition reduced flow-induced NO production via alterations in phosphorylation-mediated eNOS activity. Inhibition of TRPC1/6 or Orai1 failed to lower ATP-induced calcium entry or eNOS activation. Our results suggest that TRPC3 is a store-operated channel in BAECs and is the key regulator of ATP-induced eNOS activation, whereas flow stimulation also recruits TRPC4 into the pathway for the synthesis of NO.
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18
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Cantu JC, Tolstykh GP, Tarango M, Beier HT, Ibey BL. Caveolin-1 is Involved in Regulating the Biological Response of Cells to Nanosecond Pulsed Electric Fields. J Membr Biol 2021; 254:141-156. [PMID: 33427940 DOI: 10.1007/s00232-020-00160-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 11/18/2020] [Indexed: 01/20/2023]
Abstract
Nanosecond pulsed electric fields (nsPEFs) induce changes in the plasma membrane (PM), including PM permeabilization (termed nanoporation), allowing free passage of ions into the cell and, in certain cases, cell death. Recent studies from our laboratory show that the composition of the PM is a critical determinant of PM nanoporation. Thus, we hypothesized that the biological response to nsPEF exposure could be influenced by lipid microdomains, including caveolae, which are specialized invaginations of the PM that are enriched in cholesterol and contain aggregates of important cell signaling proteins, such as caveolin-1 (Cav1). Caveolae play a significant role in cellular signal transduction, including control of calcium influx and cell death by interaction of Cav1 with regulatory signaling proteins. Present results show that depletion of Cav1 increased the influx of calcium, while Cav1 overexpression produced the opposite effect. Additionally, Cav1 is known to bind and sequester important cell signaling proteins within caveolae, rendering the binding partners inactive. Imaging of the PM after nsPEF exposure showed localized depletion of PM Cav1 and results of co-immunoprecipitation studies showed dissociation of two critical Cav1 binding partners (transient receptor potential cation channel subfamily C1 (TRPC1) and inositol trisphosphate receptor (IP3R)) after exposure to nsPEFs. Release of TRPC1 and IP3R from Cav1 would activate downstream signaling cascades, including store-operated calcium entry, which could explain the influx in calcium after nsPEF exposure. Results of the current study establish a significant relationship between Cav1 and the activation of cell signaling pathways in response to nsPEFs.
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Affiliation(s)
- Jody C Cantu
- General Dynamics Information Technology, JBSA Fort Sam Houston, 4141 Petroleum Road, Bldg. 3260, San Antonio, TX, 78234-2644, USA.
| | - Gleb P Tolstykh
- General Dynamics Information Technology, JBSA Fort Sam Houston, 4141 Petroleum Road, Bldg. 3260, San Antonio, TX, 78234-2644, USA
| | - Melissa Tarango
- General Dynamics Information Technology, JBSA Fort Sam Houston, 4141 Petroleum Road, Bldg. 3260, San Antonio, TX, 78234-2644, USA
| | - Hope T Beier
- Air Force Research Laboratory, 711th Human Performance Wing, Airman Systems Directorate, Bioeffects Division, Optical Radiation Bioeffects Branch, JBSA Fort Sam Houston, San Antonio, TX, 78234, USA
| | - Bennett L Ibey
- Air Force Research Laboratory, 711th Human Performance Wing, Airman Systems Directorate, Bioeffects Division, Radio Frequency Bioeffects Branch, JBSA Fort Sam Houston, San Antonio, TX, 78234, USA
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19
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Moccia F, Negri S, Faris P, Berra-Romani R. Targeting the Endothelial Ca2+ Toolkit to Rescue Endothelial Dysfunction in Obesity Associated-Hypertension. Curr Med Chem 2020; 27:240-257. [PMID: 31486745 DOI: 10.2174/0929867326666190905142135] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Revised: 06/03/2019] [Accepted: 07/16/2019] [Indexed: 12/14/2022]
Abstract
BACKGROUND Obesity is a major cardiovascular risk factor which dramatically impairs endothelium- dependent vasodilation and leads to hypertension and vascular damage. The impairment of the vasomotor response to extracellular autacoids, e.g., acetylcholine, mainly depends on the reduced Nitric Oxide (NO) bioavailability, which hampers vasorelaxation in large conduit arteries. In addition, obesity may affect Endothelium-Dependent Hyperpolarization (EDH), which drives vasorelaxation in small resistance arteries and arterioles. Of note, endothelial Ca2+ signals drive NO release and trigger EDH. METHODS A structured search of bibliographic databases was carried out to retrieve the most influential, recent articles on the impairment of vasorelaxation in animal models of obesity, including obese Zucker rats, and on the remodeling of the endothelial Ca2+ toolkit under conditions that mimic obesity. Furthermore, we searched for articles discussing how dietary manipulation could be exploited to rescue Ca2+-dependent vasodilation. RESULTS We found evidence that the endothelial Ca2+ could be severely affected by obese vessels. This rearrangement could contribute to endothelial damage and is likely to be involved in the disruption of vasorelaxant mechanisms. However, several Ca2+-permeable channels, including Vanilloid Transient Receptor Potential (TRPV) 1, 3 and 4 could be stimulated by several food components to stimulate vasorelaxation in obese individuals. CONCLUSION The endothelial Ca2+ toolkit could be targeted to reduce vascular damage and rescue endothelium- dependent vasodilation in obese vessels. This hypothesis remains, however, to be probed on truly obese endothelial cells.
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Affiliation(s)
- Francesco Moccia
- Laboratory of General Physiology, Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, Pavia, Italy
| | - Sharon Negri
- Laboratory of General Physiology, Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, Pavia, Italy
| | - Pawan Faris
- Laboratory of General Physiology, Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, Pavia, Italy
| | - Roberto Berra-Romani
- Department of Biomedicine, School of Medicine, Benemérita Universidad Autónoma de Puebla, Puebla, Mexico
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20
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Holme JA, Brinchmann BC, Le Ferrec E, Lagadic-Gossmann D, Øvrevik J. Combustion Particle-Induced Changes in Calcium Homeostasis: A Contributing Factor to Vascular Disease? Cardiovasc Toxicol 2020; 19:198-209. [PMID: 30955163 DOI: 10.1007/s12012-019-09518-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Air pollution is the leading environmental risk factor for disease and premature death in the world. This is mainly due to exposure to urban air particle matter (PM), in particular, fine and ultrafine combustion-derived particles (CDP) from traffic-related air pollution. PM and CDP, including particles from diesel exhaust (DEP), and cigarette smoke have been linked to various cardiovascular diseases (CVDs) including atherosclerosis, but the underlying cellular mechanisms remain unclear. Moreover, CDP typically consist of carbon cores with a complex mixture of organic chemicals such as polycyclic aromatic hydrocarbons (PAHs) adhered. The relative contribution of the carbon core and adhered soluble components to cardiovascular effects of CDP is still a matter of discussion. In the present review, we summarize evidence showing that CDP affects intracellular calcium regulation, and argue that CDP-induced impairment of normal calcium control may be a critical cellular event through which CDP exposure contributes to development or exacerbation of cardiovascular disease. Furthermore, we highlight in vitro research suggesting that adhered organic chemicals such as PAHs may be key drivers of these responses. CDP, extractable organic material from CDP (CDP-EOM), and PAHs may increase intracellular calcium levels by interacting with calcium channels like transient receptor potential (TRP) channels, and receptors such as G protein-coupled receptors (GPCR; e.g., beta-adrenergic receptors [βAR] and protease-activated receptor 2 [PAR-2]) and the aryl hydrocarbon receptor (AhR). Clarifying a possible role of calcium signaling and mechanisms involved may increase our understanding of how air pollution contributes to CVD.
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Affiliation(s)
- Jørn A Holme
- Department of Air Pollution and Noise, Division of Infection Control, Environment and Health, Norwegian Institute of Public Health, PO Box 4404, Nydalen, 0403, Oslo, Norway.
| | - Bendik C Brinchmann
- Department of Air Pollution and Noise, Division of Infection Control, Environment and Health, Norwegian Institute of Public Health, PO Box 4404, Nydalen, 0403, Oslo, Norway
| | - Eric Le Ferrec
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé environnement et travail) - UMR_S 1085, 35000, Rennes, France
| | - Dominique Lagadic-Gossmann
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé environnement et travail) - UMR_S 1085, 35000, Rennes, France
| | - Johan Øvrevik
- Department of Air Pollution and Noise, Division of Infection Control, Environment and Health, Norwegian Institute of Public Health, PO Box 4404, Nydalen, 0403, Oslo, Norway.
- Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, Oslo, Norway.
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21
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Structure-Function Relationship and Physiological Roles of Transient Receptor Potential Canonical (TRPC) 4 and 5 Channels. Cells 2019; 9:cells9010073. [PMID: 31892199 PMCID: PMC7017149 DOI: 10.3390/cells9010073] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Revised: 12/24/2019] [Accepted: 12/24/2019] [Indexed: 12/11/2022] Open
Abstract
The study of the structure–function relationship of ion channels has been one of the most challenging goals in contemporary physiology. Revelation of the three-dimensional (3D) structure of ion channels has facilitated our understanding of many of the submolecular mechanisms inside ion channels, such as selective permeability, voltage dependency, agonist binding, and inter-subunit multimerization. Identifying the structure–function relationship of the ion channels is clinically important as well since only such knowledge can imbue potential therapeutics with practical possibilities. In a sense, recent advances in the understanding of the structure–relationship of transient receptor potential canonical (TRPC) channels look promising since human TRPC channels are calcium-permeable, non-selective cation channels expressed in many tissues such as the gastrointestinal (GI) tract, kidney, heart, vasculature, and brain. TRPC channels are known to regulate GI contractility and motility, pulmonary hypertension, right ventricular hypertrophy, podocyte injury, seizure, fear, anxiety-like behavior, and many others. In this article, we tried to elaborate recent findings of Cryo-EM (cryogenic-electron microscopy) based structural information of TRPC 4 and 5 channels and domain-specific functions of the channel, such as G-protein mediated activation mechanism, extracellular modification of the channel, homo/hetero-tetramerization, and pharmacological gating mechanisms.
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22
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Gutorov R, Peters M, Katz B, Brandwine T, Barbera NA, Levitan I, Minke B. Modulation of Transient Receptor Potential C Channel Activity by Cholesterol. Front Pharmacol 2019; 10:1487. [PMID: 31920669 PMCID: PMC6923273 DOI: 10.3389/fphar.2019.01487] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 11/15/2019] [Indexed: 12/11/2022] Open
Abstract
Changes of cholesterol level in the plasma membrane of cells have been shown to modulate ion channel function. The proposed mechanisms underlying these modulations include association of cholesterol to a single binding site at a single channel conformation, association to a highly flexible cholesterol binding site adopting multiple poses, and perturbation of lipid rafts. These perturbations have been shown to induce reversible targeting of mammalian transient receptor potential C (TRPC) channels to the cholesterol-rich membrane environment of lipid rafts. Thus, the observed inhibition of TRPC channels by methyl-β-cyclodextrin (MβCD), which induces cholesterol efflux from the plasma membrane, may result from disruption of lipid rafts. This perturbation was also shown to disrupt multimolecular signaling complexes containing TRPC channels. The Drosophila TRP and TRP-like (TRPL) channels belong to the TRPC channel subfamily. When the Drosophila TRPL channel was expressed in S2 or HEK293 cells and perfused with MβCD, the TRPL current was abolished in less than 100 s, fitting well the fast kinetic phase of cholesterol sequestration experiments in cells. It was thus suggested that the fast kinetics of TRPL channel suppression by MβCD arise from disruption of lipid rafts. Accordingly, lipid raft perturbation by cholesterol sequestration could give clues to the function of lipid environment in TRPC channel activity and its mechanism.
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Affiliation(s)
- Rita Gutorov
- Institute for Medical Research Israel-Canada (IMRIC), Edmond and Lily Safra Center for Brain Sciences (ELSC), Faculty of Medicine, The Hebrew University, Jerusalem, Israel
| | - Maximilian Peters
- Institute for Medical Research Israel-Canada (IMRIC), Edmond and Lily Safra Center for Brain Sciences (ELSC), Faculty of Medicine, The Hebrew University, Jerusalem, Israel
| | - Ben Katz
- Institute for Medical Research Israel-Canada (IMRIC), Edmond and Lily Safra Center for Brain Sciences (ELSC), Faculty of Medicine, The Hebrew University, Jerusalem, Israel
| | - Tal Brandwine
- Institute for Medical Research Israel-Canada (IMRIC), Edmond and Lily Safra Center for Brain Sciences (ELSC), Faculty of Medicine, The Hebrew University, Jerusalem, Israel
| | - Nicolas A Barbera
- Division of Pulmonary, Critical Care, Sleep and Allergy, Department of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Irena Levitan
- Division of Pulmonary, Critical Care, Sleep and Allergy, Department of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Baruch Minke
- Institute for Medical Research Israel-Canada (IMRIC), Edmond and Lily Safra Center for Brain Sciences (ELSC), Faculty of Medicine, The Hebrew University, Jerusalem, Israel
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23
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Matthaeus C, Lian X, Kunz S, Lehmann M, Zhong C, Bernert C, Lahmann I, Müller DN, Gollasch M, Daumke O. eNOS-NO-induced small blood vessel relaxation requires EHD2-dependent caveolae stabilization. PLoS One 2019; 14:e0223620. [PMID: 31600286 PMCID: PMC6786623 DOI: 10.1371/journal.pone.0223620] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 09/24/2019] [Indexed: 11/30/2022] Open
Abstract
Endothelial nitric oxide synthase (eNOS)-related vessel relaxation is a highly coordinated process that regulates blood flow and pressure and is dependent on caveolae. Here, we investigated the role of caveolar plasma membrane stabilization by the dynamin-related ATPase EHD2 on eNOS-nitric oxide (NO)-dependent vessel relaxation. Loss of EHD2 in small arteries led to increased numbers of caveolae that were detached from the plasma membrane. Concomitantly, impaired relaxation of mesenteric arteries and reduced running wheel activity were observed in EHD2 knockout mice. EHD2 deletion or knockdown led to decreased production of nitric oxide (NO) although eNOS expression levels were not changed. Super-resolution imaging revealed that eNOS was redistributed from the plasma membrane to internalized detached caveolae in EHD2-lacking tissue or cells. Following an ATP stimulus, reduced cytosolic Ca2+ peaks were recorded in human umbilical vein endothelial cells (HUVECs) lacking EHD2. Our data suggest that EHD2-controlled caveolar dynamics orchestrates the activity and regulation of eNOS/NO and Ca2+ channel localization at the plasma membrane.
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Affiliation(s)
- Claudia Matthaeus
- Crystallography, Max-Delbrück-Center for Molecular Medicine, Berlin, Germany
| | - Xiaoming Lian
- Charité—Universitätsmedizin Berlin, Experimental and Clinical Research Center (ECRC), Campus Buch, Berlin, Germany
| | - Séverine Kunz
- Electron Microscopy Core Facility, Max-Delbrück-Center for Molecular Medicine, Berlin, Germany
| | - Martin Lehmann
- Department of Molecular Pharmacology & Cell Biology and Imaging Core Facility, Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin, Germany
| | - Cheng Zhong
- Charité—Universitätsmedizin Berlin, Experimental and Clinical Research Center (ECRC), Campus Buch, Berlin, Germany
| | - Carola Bernert
- Crystallography, Max-Delbrück-Center for Molecular Medicine, Berlin, Germany
| | - Ines Lahmann
- Signal Transduction/Developmental Biology, Max-Delbrück-Center for Molecular Medicine, Berlin, Germany
| | - Dominik N. Müller
- Experimental & Clinical Research Center, a cooperation between Charité Universitätsmedizin Berlin and Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Maik Gollasch
- Charité—Universitätsmedizin Berlin, Experimental and Clinical Research Center (ECRC), Campus Buch, Berlin, Germany
- Charité—Universitätsmedizin Berlin, Medical Clinic for Nephrology and Internal Intensive Care, Campus Virchow, Berlin, Germany
| | - Oliver Daumke
- Crystallography, Max-Delbrück-Center for Molecular Medicine, Berlin, Germany
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
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24
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Zhang B, Paffett ML, Naik JS, Jernigan NL, Walker BR, Resta TC. Cholesterol Regulation of Pulmonary Endothelial Calcium Homeostasis. CURRENT TOPICS IN MEMBRANES 2018; 82:53-91. [PMID: 30360783 DOI: 10.1016/bs.ctm.2018.09.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Cholesterol is a key structural component and regulator of lipid raft signaling platforms critical for cell function. Such regulation may involve changes in the biophysical properties of lipid microdomains or direct protein-sterol interactions that alter the function of ion channels, receptors, enzymes, and membrane structural proteins. Recent studies have implicated abnormal membrane cholesterol levels in mediating endothelial dysfunction that is characteristic of pulmonary hypertensive disorders, including that resulting from long-term exposure to hypoxia. Endothelial dysfunction in this setting is characterized by impaired pulmonary endothelial calcium entry and an associated imbalance that favors production vasoconstrictor and mitogenic factors that contribute to pulmonary hypertension. Here we review current knowledge of cholesterol regulation of pulmonary endothelial Ca2+ homeostasis, focusing on the role of membrane cholesterol in mediating agonist-induced Ca2+ entry and its components in the normal and hypertensive pulmonary circulation.
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Affiliation(s)
- Bojun Zhang
- Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico, Albuquerque, NM, United States
| | - Michael L Paffett
- Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico, Albuquerque, NM, United States
| | - Jay S Naik
- Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico, Albuquerque, NM, United States
| | - Nikki L Jernigan
- Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico, Albuquerque, NM, United States
| | - Benjimen R Walker
- Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico, Albuquerque, NM, United States
| | - Thomas C Resta
- Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico, Albuquerque, NM, United States.
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Liu Y, Yoo E, Mahler GJ, Doiron AL. Endothelial barrier dysfunction induced by nanoparticle exposure through actin remodeling via caveolae/raft-regulated calcium signalling. NANOIMPACT 2018; 11:82-91. [PMID: 30238068 PMCID: PMC6139665 DOI: 10.1016/j.impact.2018.02.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The rapid development of modern nanotechnology has resulted in nanomaterial being use in nearly all applications of life, raising the potential risk of nanomaterial exposure alongside the need to design safe and effective materials. Previous work has demonstrated a specific effect of gold nanoparticles (GNPs) of approximately 20 nm on endothelial barrier function in vitro. To expand our understanding of this size-specific effect, titanium dioxide, silicon dioxide, and polystyrene nanoparticles (NPs) in this similar size range were studied. All tested nanoparticles were found to have minimal effects on cell viability, but exhibited a significant detrimental effect on endothelial barrier function. Nanoparticles in the size range of 20 to 30 nm were internalized by endothelial cells through caveolae/raft-mediated endocytosis, causing intracellular calcium elevation by approximately 30% at 2 hours after administration, and triggering myosin light chain kinase (MLCK)-regulated actomyosin contraction. These effects culminated in an increase in endothelial monolayer permeability across all particle types within the 20-30 nm range. This nanoparticle exposure-induced endothelial barrier dysfunction may provide valuable information for designing safer nanomaterials or potential applications of this nanoparticle exposure-induced permeability effect in biomedicine.
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Affiliation(s)
- Yizhong Liu
- Department of Biomedical Engineering, Binghamton University,
Binghamton, USA
| | - Eunsoo Yoo
- Department of Biomedical Engineering, Binghamton University,
Binghamton, USA
| | - Gretchen J. Mahler
- Department of Biomedical Engineering, Binghamton University,
Binghamton, USA
| | - Amber L. Doiron
- Department of Biomedical Engineering, Binghamton University,
Binghamton, USA
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Plasma membrane insertion of KCa2.3 (SK3) is dependent upon the SNARE proteins, syntaxin-4 and SNAP23. PLoS One 2018; 13:e0196717. [PMID: 29768434 PMCID: PMC5955555 DOI: 10.1371/journal.pone.0196717] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 04/18/2018] [Indexed: 02/03/2023] Open
Abstract
We previously demonstrated endocytosis of KCa2.3 is caveolin-1-, dynamin II- and Rab5-dependent. KCa2.3 then enters Rab35/EPI64C- and RME-1-containing recycling endosomes and is returned to the plasma membrane (PM). Herein, we report on the mechanism by which KCa2.3 is inserted into the PM during recycling and following exit from the Golgi. We demonstrate KCa2.3 colocalizes with SNAP-23 and Syntaxin-4 in the PM of HEK and endothelial cells by confocal immunofluorescence microscopy. We further show KCa2.3 can be co-immunoprecipitated with SNAP-23 and Syntaxin-4. Overexpression of either Syntaxin-4 or SNAP-23 increased PM expression of KCa2.3, whereas shRNA-mediated knockdown of these SNARE proteins significantly decreased PM KCa2.3 expression, as assessed by cell surface biotinylation. Whole-cell patch clamp studies confirmed knockdown of SNAP-23 significantly decreased the apamin sensitive, KCa2.3 current. Using standard biotinylation/stripping methods, we demonstrate shRNA mediated knockdown of SNAP-23 inhibits recycling of KCa2.3 following endocytosis, whereas scrambled shRNA had no effect. Finally, using biotin ligase acceptor peptide (BLAP)-tagged KCa2.3, coupled with ER-resident biotin ligase (BirA), channels could be biotinylated in the ER after which we evaluated their rate of insertion into the PM following Golgi exit. We demonstrate knockdown of SNAP-23 significantly slows the rate of Golgi to PM delivery of KCa2.3. The inhibition of both recycling and PM delivery of newly synthesized KCa2.3 channels likely accounts for the decreased PM expression observed following knockdown of these SNARE proteins. In total, our results suggest insertion of KCa2.3 into the PM depends upon the SNARE proteins, Syntaxin-4 and SNAP-23.
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Filippini A, Sica G, D'Alessio A. The caveolar membrane system in endothelium: From cell signaling to vascular pathology. J Cell Biochem 2018; 119:5060-5071. [PMID: 29637636 DOI: 10.1002/jcb.26793] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 02/16/2018] [Indexed: 12/12/2022]
Abstract
Caveolae are 50- to 100-nm cholesterol and glycosphingolipid-rich flask-shaped invaginations commonly observed in many terminally differentiated cells. These organelles have been described in many cell types and are particularly abundant in endothelial cells, where they have been involved in the regulation of certain signaling pathways. Specific scaffolding proteins termed caveolins, along with the more recently discovered members of the cavin family, represent the major protein components during caveolae biogenesis. In addition, multiple studies aimed to investigate the expression and the regulation of these proteins significantly contributed to elucidate the role of caveolae and caveolins in endothelial cell physiology and disease. The aim of this review is to survey recent evidence of the involvement of the caveolar network in endothelial cell biology and endothelial cell dysfunction.
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Affiliation(s)
- Antonio Filippini
- Department of Anatomy, Histology, Forensic Medicine and Orthopaedics, Unit of Histology and Medical Embryology, Sapienza University of Rome, Rome, Italy
| | - Gigliola Sica
- Istituto di Istologia ed Embriologia, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Alessio D'Alessio
- Istituto di Istologia ed Embriologia, Università Cattolica del Sacro Cuore, Rome, Italy
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Yang K, Zhao M, Huang J, Zhang C, Zheng Q, Chen Y, Jiang H, Lu W, Wang J. Pharmacological activation of PPARγ inhibits hypoxia-induced proliferation through a caveolin-1-targeted and -dependent mechanism in PASMCs. Am J Physiol Cell Physiol 2018; 314:C428-C438. [PMID: 29351409 DOI: 10.1152/ajpcell.00143.2017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Previously, we and others have demonstrated that activation of peroxisome proliferator-activated receptor γ (PPARγ) by specific pharmacological agonists inhibits the pathogenesis of chronic hypoxia-induced pulmonary hypertension (CHPH) by suppressing the proliferation and migration in distal pulmonary arterial smooth muscle cells (PASMCs). Moreover, these beneficial effects of PPARγ are mediated by targeting the intracellular calcium homeostasis and store-operated calcium channel (SOCC) proteins, including the main caveolae component caveolin-1. However, other than the caveolin-1 targeted mechanism, in this study, we further uncovered a caveolin-1 dependent mechanism within the activation of PPARγ by the specific agonist GW1929. First, effective knockdown of caveolin-1 by small-interfering RNA (siRNA) markedly abolished the upregulation of GW1929 on PPARγ expression at both mRNA and protein levels; Then, in HEK293T, which has previously been reported with low endogenous caveolin-1 expression, exogenous expression of caveolin-1 significantly enhanced the upregulation of GW1929 on PPARγ expression compared with nontransfection control. In addition, inhibition of PPARγ by either siRNA or pharmacological inhibitor T0070907 led to increased phosphorylation of cellular mitogen-activated protein kinases ERK1/2 and p38. In parallel, GW1929 dramatically decreased the expression of the proliferative regulators (cyclin D1 and PCNA), whereas it increased the apoptotic factors (p21, p53, and mdm2) in hypoxic PASMCs. Furthermore, these effects of GW1929 could be partially reversed by recovery of the drug treatment. In combination, PPARγ activation by GW1929 reversibly drove the cell toward an antiproliferative and proapoptotic phenotype in a caveolin-1-dependent and -targeted mechanism.
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Affiliation(s)
- Kai Yang
- State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Respiratory Diseases, The First Affiliated Hospital of Guangzhou Medical University , Guangzhou, Guangdong , China
| | - Mingming Zhao
- Laboratory of Molecular Biology and Immunology, National Institute on Aging, National Institutes of Health , Baltimore, Maryland
| | - Junyi Huang
- State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Respiratory Diseases, The First Affiliated Hospital of Guangzhou Medical University , Guangzhou, Guangdong , China
| | - Chenting Zhang
- State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Respiratory Diseases, The First Affiliated Hospital of Guangzhou Medical University , Guangzhou, Guangdong , China
| | - Qiuyu Zheng
- State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Respiratory Diseases, The First Affiliated Hospital of Guangzhou Medical University , Guangzhou, Guangdong , China
| | - Yuqin Chen
- State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Respiratory Diseases, The First Affiliated Hospital of Guangzhou Medical University , Guangzhou, Guangdong , China
| | - Haiyang Jiang
- Division of Pulmonary and Critical Care Medicine, The Johns Hopkins University School of Medicine , Baltimore, Maryland
| | - Wenju Lu
- State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Respiratory Diseases, The First Affiliated Hospital of Guangzhou Medical University , Guangzhou, Guangdong , China
| | - Jian Wang
- State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Respiratory Diseases, The First Affiliated Hospital of Guangzhou Medical University , Guangzhou, Guangdong , China.,Division of Translational and Regenerative Medicine, Department of Medicine, University of Arizona College of Medicine , Tucson, Arizona
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29
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Kuo A, Lee MY, Yang K, Gross RW, Sessa WC. Caveolin-1 regulates lipid droplet metabolism in endothelial cells via autocrine prostacyclin-stimulated, cAMP-mediated lipolysis. J Biol Chem 2017; 293:973-983. [PMID: 29203526 DOI: 10.1074/jbc.ra117.000980] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 11/28/2017] [Indexed: 11/06/2022] Open
Abstract
Lipid droplets (LD) are dynamic organelles involved in intracellular lipid metabolism in almost all eukaryotic cells, and LD-associated proteins tightly regulate their dynamics. One LD coat protein is caveolin-1 (Cav-1), an essential component for caveola assembly in highly differentiated cells, including adipocytes, smooth muscle cells, and endothelial cells (EC). However, the role of Cav-1 in LD dynamics is unclear. Here we report that EC lacking Cav-1 exhibit impaired LD formation. The decreased LD formation is due to enhanced lipolysis and not caused by reduced triglyceride synthesis or fatty acid uptake. Mechanistically, the absence of Cav-1 increased cAMP/PKA signaling in EC, as indicated by elevated phosphorylation of hormone-sensitive lipase and increased lipolysis. Unexpectedly, we also observed enhanced autocrine production of prostaglandin I2 (PGI2, also called prostacyclin) in Cav-1 KO EC, and this PGI2 increase appeared to stimulate cAMP/PKA pathways, contributing to the enhanced lipolysis in Cav-1 KO cells. Our results reveal an unanticipated role of Cav-1 in regulating lipolysis in non-adipose tissue, indicating that Cav-1 is required for LD metabolism in EC and that it regulates cAMP-dependent lipolysis in part via the autocrine production of PGI2.
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Affiliation(s)
- Andrew Kuo
- From the Vascular Biology and Therapeutics Program and.,Cell Biology, Yale University School of Medicine, New Haven, Connecticut 06510
| | - Monica Y Lee
- From the Vascular Biology and Therapeutics Program and.,Departments of Pharmacology and
| | - Kui Yang
- the Department of Medicine and Developmental Biology, Division of Bioorganic Chemistry and Molecular Pharmacology, Washington University School of Medicine, St. Louis, Missouri 63110, and.,the Department of Chemistry, Washington University, St. Louis, Missouri 63130
| | - Richard W Gross
- the Department of Medicine and Developmental Biology, Division of Bioorganic Chemistry and Molecular Pharmacology, Washington University School of Medicine, St. Louis, Missouri 63110, and.,the Department of Chemistry, Washington University, St. Louis, Missouri 63130
| | - William C Sessa
- From the Vascular Biology and Therapeutics Program and .,Departments of Pharmacology and
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Zhang B, Naik JS, Jernigan NL, Walker BR, Resta TC. Reduced membrane cholesterol after chronic hypoxia limits Orai1-mediated pulmonary endothelial Ca 2+ entry. Am J Physiol Heart Circ Physiol 2017; 314:H359-H369. [PMID: 29101179 DOI: 10.1152/ajpheart.00540.2017] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Endothelial dysfunction in chronic hypoxia (CH)-induced pulmonary hypertension is characterized by reduced store-operated Ca2+ entry (SOCE) and diminished Ca2+-dependent production of endothelium-derived vasodilators. We recently reported that SOCE in pulmonary arterial endothelial cells (PAECs) is tightly regulated by membrane cholesterol and that decreased membrane cholesterol is responsible for impaired SOCE after CH. However, the ion channels involved in cholesterol-sensitive SOCE are unknown. We hypothesized that cholesterol facilitates SOCE in PAECs through the interaction of Orai1 and stromal interaction molecule 1 (STIM1). The role of cholesterol in Orai1-mediated SOCE was initially assessed using CH exposure in rats (4 wk, 380 mmHg) as a physiological stimulus to decrease PAEC cholesterol. The effects of Orai1 inhibition with AnCoA4 on SOCE were examined in isolated PAEC sheets from control and CH rats after cholesterol supplementation, substitution of endogenous cholesterol with epicholesterol (Epichol), or vehicle treatment. Whereas cholesterol restored endothelial SOCE in CH rats, both Epichol and AnCoA4 attenuated SOCE only in normoxic controls. The Orai1 inhibitor had no further effect in cells pretreated with Epichol. Using cultured pulmonary endothelial cells to allow better mechanistic analysis of the molecular components of cholesterol-regulated SOCE, we found that Epichol, AnCoA4, and Orai1 siRNA each inhibited SOCE compared with their respective controls. Epichol had no additional effect after knockdown of Orai1. Furthermore, Epichol substitution significantly reduced STIM1-Orai1 interactions as assessed by a proximity ligation assay. We conclude that membrane cholesterol is required for the STIM1-Orai1 interaction necessary to elicit endothelial SOCE. Furthermore, reduced PAEC membrane cholesterol after CH limits Orai1-mediated SOCE. NEW & NOTEWORTHY This research demonstrates a novel contribution of cholesterol to regulate the interaction of Orai1 and stromal interaction molecule 1 required for pulmonary endothelial store-operated Ca2+ entry. The results provide a mechanistic basis for impaired pulmonary endothelial Ca2+ influx after chronic hypoxia that may contribute to pulmonary hypertension.
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Affiliation(s)
- Bojun Zhang
- Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico Health Sciences Center , Albuquerque, New Mexico
| | - Jay S Naik
- Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico Health Sciences Center , Albuquerque, New Mexico
| | - Nikki L Jernigan
- Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico Health Sciences Center , Albuquerque, New Mexico
| | - Benjimen R Walker
- Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico Health Sciences Center , Albuquerque, New Mexico
| | - Thomas C Resta
- Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico Health Sciences Center , Albuquerque, New Mexico
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Zhang B, Naik JS, Jernigan NL, Walker BR, Resta TC. Reduced membrane cholesterol limits pulmonary endothelial Ca 2+ entry after chronic hypoxia. Am J Physiol Heart Circ Physiol 2017; 312:H1176-H1184. [PMID: 28364016 DOI: 10.1152/ajpheart.00097.2017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Revised: 03/17/2017] [Accepted: 03/24/2017] [Indexed: 12/22/2022]
Abstract
Chronic hypoxia (CH)-induced pulmonary hypertension is associated with diminished production of endothelium-derived Ca2+-dependent vasodilators such as nitric oxide. Interestingly, ATP-induced endothelial Ca2+ entry as well as membrane cholesterol (Chol) are decreased in pulmonary arteries from CH rats (4 wk, barometric pressure = 380 Torr) compared with normoxic controls. Store-operated Ca2+ entry (SOCE) and depolarization-induced Ca2+ entry are major components of the response to ATP and are similarly decreased after CH. We hypothesized that membrane Chol facilitates both SOCE and depolarization-induced pulmonary endothelial Ca2+ entry and that CH attenuates these responses by decreasing membrane Chol. To test these hypotheses, we administered Chol or epicholesterol (Epichol) to acutely isolated pulmonary arterial endothelial cells (PAECs) from control and CH rats to either supplement or replace native Chol, respectively. The efficacy of membrane Chol manipulation was confirmed by filipin staining. Epichol greatly reduced ATP-induced Ca2+ influx in PAECs from control rats. Whereas Epichol similarly blunted endothelial SOCE in PAECs from both groups, Chol supplementation restored diminished SOCE in PAECs from CH rats while having no effect in controls. Similar effects of Chol manipulation on PAEC Ca2+ influx were observed in response to a depolarizing stimulus of KCl. Furthermore, KCl-induced Ca2+ entry was inhibited by the T-type Ca2+ channel antagonist mibefradil but not the L-type Ca2+ channel inhibitor diltiazem. We conclude that PAEC membrane Chol is required for ATP-induced Ca2+ entry and its two components, SOCE and depolarization-induced Ca2+ entry, and that reduced Ca2+ entry after CH may be due to loss of this key regulator.NEW & NOTEWORTHY This research is the first to examine the direct role of membrane cholesterol in regulating pulmonary endothelial agonist-induced Ca2+ entry and its components. The results provide a potential mechanism by which chronic hypoxia impairs pulmonary endothelial Ca2+ influx, which may contribute to pulmonary hypertension.
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Affiliation(s)
- Bojun Zhang
- Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico
| | - Jay S Naik
- Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico
| | - Nikki L Jernigan
- Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico
| | - Benjimen R Walker
- Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico
| | - Thomas C Resta
- Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico
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Busija AR, Patel HH, Insel PA. Caveolins and cavins in the trafficking, maturation, and degradation of caveolae: implications for cell physiology. Am J Physiol Cell Physiol 2017; 312:C459-C477. [PMID: 28122734 DOI: 10.1152/ajpcell.00355.2016] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 01/23/2017] [Accepted: 01/24/2017] [Indexed: 01/09/2023]
Abstract
Caveolins (Cavs) are ~20 kDa scaffolding proteins that assemble as oligomeric complexes in lipid raft domains to form caveolae, flask-shaped plasma membrane (PM) invaginations. Caveolae ("little caves") require lipid-lipid, protein-lipid, and protein-protein interactions that can modulate the localization, conformational stability, ligand affinity, effector specificity, and other functions of proteins that are partners of Cavs. Cavs are assembled into small oligomers in the endoplasmic reticulum (ER), transported to the Golgi for assembly with cholesterol and other oligomers, and then exported to the PM as an intact coat complex. At the PM, cavins, ~50 kDa adapter proteins, oligomerize into an outer coat complex that remodels the membrane into caveolae. The structure of caveolae protects their contents (i.e., lipids and proteins) from degradation. Cellular changes, including signal transduction effects, can destabilize caveolae and produce cavin dissociation, restructuring of Cav oligomers, ubiquitination, internalization, and degradation. In this review, we provide a perspective of the life cycle (biogenesis, degradation), composition, and physiologic roles of Cavs and caveolae and identify unanswered questions regarding the roles of Cavs and cavins in caveolae and in regulating cell physiology.1.
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Affiliation(s)
- Anna R Busija
- Department of Anesthesiology, University of California, San Diego, La Jolla, California.,Department of Pharmacology, University of California, San Diego, La Jolla, California
| | - Hemal H Patel
- Department of Anesthesiology, University of California, San Diego, La Jolla, California
| | - Paul A Insel
- Department of Medicine, University of California, San Diego, La Jolla, California; and .,Department of Pharmacology, University of California, San Diego, La Jolla, California
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Subedi KP, Ong HL, Ambudkar IS. Assembly of ER-PM Junctions: A Critical Determinant in the Regulation of SOCE and TRPC1. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 981:253-276. [PMID: 29594865 DOI: 10.1007/978-3-319-55858-5_11] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Store-operated calcium entry (SOCE), a unique plasma membrane Ca2+ entry mechanism, is activated when ER-[Ca2+] is decreased. SOCE is mediated via the primary channel, Orai1, as well as others such as TRPC1. STIM1 and STIM2 are ER-Ca2+ sensor proteins that regulate Orai1 and TRPC1. SOCE requires assembly of STIM proteins with the plasma membrane channels which occurs within distinct regions in the cell that have been termed as endoplasmic reticulum (ER)-plasma membrane (PM) junctions. The PM and ER are in close proximity to each other within this region, which allows STIM1 in the ER to interact with and activate either Orai1 or TRPC1 in the plasma membrane. Activation and regulation of SOCE involves dynamic assembly of various components that are involved in mediating Ca2+ entry as well as those that determine the formation and stabilization of the junctions. These components include proteins in the cytosol, ER and PM, as well as lipids in the PM. Recent studies have also suggested that SOCE and its components are compartmentalized within ER-PM junctions and that this process might require remodeling of the plasma membrane lipids and reorganization of structural and scaffolding proteins. Such compartmentalization leads to the generation of spatially- and temporally-controlled Ca2+signals that are critical for regulating many downstream cellular functions.
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Affiliation(s)
- Krishna P Subedi
- Secretory Physiology Section, Molecular Physiology and Therapeutics Branch, NIDCR, NIH, Bethesda, MD, USA
| | - Hwei Ling Ong
- Secretory Physiology Section, Molecular Physiology and Therapeutics Branch, NIDCR, NIH, Bethesda, MD, USA
| | - Indu S Ambudkar
- Secretory Physiology Section, Molecular Physiology and Therapeutics Branch, NIDCR, NIH, Bethesda, MD, USA.
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STIM-TRP Pathways and Microdomain Organization: Contribution of TRPC1 in Store-Operated Ca 2+ Entry: Impact on Ca 2+ Signaling and Cell Function. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 993:159-188. [PMID: 28900914 DOI: 10.1007/978-3-319-57732-6_9] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Store-operated calcium entry (SOCE) is a ubiquitous Ca2+ entry pathway that is activated in response to depletion of ER-Ca2+ stores and critically controls the regulation of physiological functions in a wide variety of cell types. The transient receptor potential canonical (TRPC) channels (TRPCs 1-7), which are activated by stimuli leading to PIP2 hydrolysis, were first identified as molecular components of SOCE channels. While TRPC1 was associated with SOCE and regulation of function in several cell types, none of the TRPC members displayed I CRAC, the store-operated current identified in lymphocytes and mast cells. Intensive search finally led to the identification of Orai1 and STIM1 as the primary components of the CRAC channel. Orai1 was established as the pore-forming channel protein and STIM1 as the ER-Ca2+ sensor protein involved in activation of Orai1. STIM1 also activates TRPC1 via a distinct domain in its C-terminus. However, TRPC1 function depends on Orai1-mediated Ca2+ entry, which triggers recruitment of TRPC1 into the plasma membrane where it is activated by STIM1. TRPC1 and Orai1 form distinct store-operated Ca2+ channels that regulate specific cellular functions. It is now clearly established that regulation of TRPC1 trafficking can change plasma membrane levels of the channel, the phenotype of the store-operated Ca2+ current, as well as pattern of SOCE-mediated [Ca2+]i signals. Thus, TRPC1 is activated downstream of Orai1 and modifies the initial [Ca2+]i signal generated by Orai1. This review will highlight current concepts of the activation and regulation of TRPC1 channels and its impact on cell function.
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Peters M, Katz B, Lev S, Zaguri R, Gutorov R, Minke B. Depletion of Membrane Cholesterol Suppresses Drosophila Transient Receptor Potential-Like (TRPL) Channel Activity. CURRENT TOPICS IN MEMBRANES 2017; 80:233-254. [DOI: 10.1016/bs.ctm.2017.05.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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36
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Jiao HX, Mu YP, Gui LX, Yan FR, Lin DC, Sham JS, Lin MJ. Increase in caveolae and caveolin-1 expression modulates agonist-induced contraction and store- and receptor-operated Ca2+ entry in pulmonary arteries of pulmonary hypertensive rats. Vascul Pharmacol 2016; 84:55-66. [DOI: 10.1016/j.vph.2016.06.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 05/03/2016] [Accepted: 06/11/2016] [Indexed: 10/21/2022]
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37
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Svobodova B, Groschner K. Reprint of "Mechanisms of lipid regulation and lipid gating in TRPC channels". Cell Calcium 2016; 60:133-41. [PMID: 27431463 DOI: 10.1016/j.ceca.2016.06.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 03/24/2016] [Accepted: 03/25/2016] [Indexed: 01/04/2023]
Abstract
TRPC proteins form cation channels that integrate and relay cellular signals by mechanisms involving lipid recognition and lipid-dependent gating. The lipohilic/amphiphilic molecules that function as cellular activators or modulators of TRPC proteins span a wide range of chemical structures. In this context, cellular redox balance is likely linked to the lipid recognition/gating features of TRPC channels. Both classical ligand-protein interactions as well as indirect and promiscuous sensory mechanisms have been proposed. Some of the recognition processes are suggested to involve ancillary lipid-binding scaffolds or regulators as well as dynamic protein-protein interactions determined by bilayer architecture. A complex interplay of protein-protein and protein-lipid interactions is likely to govern the gating and/or plasma membrane recruitment of TRPC channels, thereby providing a distinguished platform for signal integration and coincident signal detection. Both the primary molecular event(s) of lipid recognition by TRPC channels as well as the transformation of these events into distinct gating movements is poorly understood at the molecular level, and it remains elusive whether lipid sensing in TRPCs is conferred to a distinct sensor domain. Recent structural information on the molecular action of lipophilic activators in distantly related members of the TRP superfamily encourages speculations on TRPC gating mechanisms involved in lipid recognition/gating. This review aims to provide an update on the current understanding of the lipid-dependent control of TRPC channels with focus on the TRPC lipid sensing, signal-integration hub and a short discussion of potential links to redox signaling.
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Affiliation(s)
- Barbora Svobodova
- Institute of Biophysics, Medical University of Graz, A-8010 Graz, Austria
| | - Klaus Groschner
- Institute of Biophysics, Medical University of Graz, A-8010 Graz, Austria.
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Mechanisms of lipid regulation and lipid gating in TRPC channels. Cell Calcium 2016; 59:271-9. [PMID: 27125985 DOI: 10.1016/j.ceca.2016.03.012] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 03/24/2016] [Accepted: 03/25/2016] [Indexed: 12/15/2022]
Abstract
TRPC proteins form cation channels that integrate and relay cellular signals by mechanisms involving lipid recognition and lipid-dependent gating. The lipohilic/amphiphilic molecules that function as cellular activators or modulators of TRPC proteins span a wide range of chemical structures. In this context, cellular redox balance is likely linked to the lipid recognition/gating features of TRPC channels. Both classical ligand-protein interactions as well as indirect and promiscuous sensory mechanisms have been proposed. Some of the recognition processes are suggested to involve ancillary lipid-binding scaffolds or regulators as well as dynamic protein-protein interactions determined by bilayer architecture. A complex interplay of protein-protein and protein-lipid interactions is likely to govern the gating and/or plasma membrane recruitment of TRPC channels, thereby providing a distinguished platform for signal integration and coincident signal detection. Both the primary molecular event(s) of lipid recognition by TRPC channels as well as the transformation of these events into distinct gating movements is poorly understood at the molecular level, and it remains elusive whether lipid sensing in TRPCs is conferred to a distinct sensor domain. Recent structural information on the molecular action of lipophilic activators in distantly related members of the TRP superfamily encourages speculations on TRPC gating mechanisms involved in lipid recognition/gating. This review aims to provide an update on the current understanding of the lipid-dependent control of TRPC channels with focus on the TRPC lipid sensing, signal-integration hub and a short discussion of potential links to redox signaling.
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Yang K, Lu W, Jiang Q, Yun X, Zhao M, Jiang H, Wang J. Peroxisome Proliferator-Activated Receptor γ-Mediated Inhibition on Hypoxia-Triggered Store-Operated Calcium Entry. A Caveolin-1-Dependent Mechanism. Am J Respir Cell Mol Biol 2016; 53:882-92. [PMID: 26020612 DOI: 10.1165/rcmb.2015-0002oc] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Our previous publication demonstrated that peroxisome proliferator-activated receptor γ (PPARγ) inhibits the pathogenesis of chronic hypoxia (CH)-induced pulmonary hypertension by targeting store-operated calcium entry (SOCE) in rat distal pulmonary arterial smooth muscle cells (PASMCs). In this study, we aim to determine the role of a membrane scaffolding protein, caveolin-1, during the suppressive process of PPARγ on SOCE. Adult (6-8 weeks) male Wistar rats (200-250 g) were exposed to CH (10% O2) for 21 days to establish CH-induced pulmonary hypertension. Primary cultured rat distal PASMCs were applied for the molecular biological experiments. First, hypoxic exposure led to 2.5-fold and 1-fold increases of caveolin-1 protein expression in the distal pulmonary arteries and PASMCs, respectively. Second, effective knockdown of caveolin-1 significantly reduced hypoxia-induced SOCE for 58.2% and 41.5%, measured by Mn(2+) quenching and extracellular Ca(2+) restoration experiments, respectively. These results suggested that caveolin-1 acts as a crucial regulator of SOCE, and hypoxia-up-regulated caveolin-1 largely accounts for hypoxia-elevated SOCE in PASMCs. Then, by using a high-potency PPARγ agonist, GW1929, we detected that PPARγ activation inhibited SOCE and caveolin-1 protein for 62.5% and 59.8% under hypoxia, respectively, suggesting that caveolin-1 also acts as a key target during the suppressive process of PPARγ on SOCE in PASMCs. Moreover, by using effective small interfering RNAs against PPARγ and caveolin-1, and PPARγ antagonist, T0070907, we observed that PPARγ plays an inhibitory role on caveolin-1 protein by promoting its lysosomal degradation, without affecting the messenger RNA level. PPARγ inhibits SOCE, at least partially, by suppressing cellular caveolin-1 protein in PASMCs.
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Affiliation(s)
- Kai Yang
- 1 State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Respiratory Diseases, the First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China.,2 Division of Pulmonary and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland; and
| | - Wenju Lu
- 1 State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Respiratory Diseases, the First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China.,2 Division of Pulmonary and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland; and
| | - Qian Jiang
- 1 State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Respiratory Diseases, the First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China.,2 Division of Pulmonary and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland; and
| | - Xin Yun
- 1 State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Respiratory Diseases, the First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China.,2 Division of Pulmonary and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland; and
| | - Mingming Zhao
- 3 Laboratory of Molecular Biology and Immunology, National Institute on Aging, Baltimore, Maryland
| | - Haiyang Jiang
- 2 Division of Pulmonary and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland; and
| | - Jian Wang
- 1 State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Respiratory Diseases, the First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China.,4 Division of Pulmonary, the People's Hospital of Inner Mongolia, Hohhot, Inner Mongolia, China.,2 Division of Pulmonary and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland; and
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Prole DL, Taylor CW. Inositol 1,4,5-trisphosphate receptors and their protein partners as signalling hubs. J Physiol 2016; 594:2849-66. [PMID: 26830355 PMCID: PMC4887697 DOI: 10.1113/jp271139] [Citation(s) in RCA: 107] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 11/06/2015] [Indexed: 01/26/2023] Open
Abstract
Inositol 1,4,5‐trisphosphate receptors (IP3Rs) are expressed in nearly all animal cells, where they mediate the release of Ca2+ from intracellular stores. The complex spatial and temporal organization of the ensuing intracellular Ca2+ signals allows selective regulation of diverse physiological responses. Interactions of IP3Rs with other proteins contribute to the specificity and speed of Ca2+ signalling pathways, and to their capacity to integrate information from other signalling pathways. In this review, we provide a comprehensive survey of the proteins proposed to interact with IP3Rs and the functional effects that these interactions produce. Interacting proteins can determine the activity of IP3Rs, facilitate their regulation by multiple signalling pathways and direct the Ca2+ that they release to specific targets. We suggest that IP3Rs function as signalling hubs through which diverse inputs are processed and then emerge as cytosolic Ca2+ signals.
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Affiliation(s)
- David L Prole
- Department of Pharmacology, University of Cambridge, Cambridge, CB2 1PD, UK
| | - Colin W Taylor
- Department of Pharmacology, University of Cambridge, Cambridge, CB2 1PD, UK
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Ohya S, Kito H, Hatano N, Muraki K. Recent advances in therapeutic strategies that focus on the regulation of ion channel expression. Pharmacol Ther 2016; 160:11-43. [PMID: 26896566 DOI: 10.1016/j.pharmthera.2016.02.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
A number of different ion channel types are involved in cell signaling networks, and homeostatic regulatory mechanisms contribute to the control of ion channel expression. Profiling of global gene expression using microarray technology has recently provided novel insights into the molecular mechanisms underlying the homeostatic and pathological control of ion channel expression. It has demonstrated that the dysregulation of ion channel expression is associated with the pathogenesis of neural, cardiovascular, and immune diseases as well as cancers. In addition to the transcriptional, translational, and post-translational regulation of ion channels, potentially important evidence on the mechanisms controlling ion channel expression has recently been accumulated. The regulation of alternative pre-mRNA splicing is therefore a novel therapeutic strategy for the treatment of dominant-negative splicing disorders. Epigenetic modification plays a key role in various pathological conditions through the regulation of pluripotency genes. Inhibitors of pre-mRNA splicing and histone deacetyalase/methyltransferase have potential as potent therapeutic drugs for cancers and autoimmune and inflammatory diseases. Moreover, membrane-anchoring proteins, lysosomal and proteasomal degradation-related molecules, auxiliary subunits, and pharmacological agents alter the protein folding, membrane trafficking, and post-translational modifications of ion channels, and are linked to expression-defect channelopathies. In this review, we focused on recent insights into the transcriptional, spliceosomal, epigenetic, and proteasomal regulation of ion channel expression: Ca(2+) channels (TRPC/TRPV/TRPM/TRPA/Orai), K(+) channels (voltage-gated, KV/Ca(2+)-activated, KCa/two-pore domain, K2P/inward-rectifier, Kir), and Ca(2+)-activated Cl(-) channels (TMEM16A/TMEM16B). Furthermore, this review highlights expression of these ion channels in expression-defect channelopathies.
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Affiliation(s)
- Susumu Ohya
- Department of Pharmacology, Division of Pathological Sciences, Kyoto Pharmaceutical University, Kyoto 607-8414, Japan.
| | - Hiroaki Kito
- Department of Pharmacology, Division of Pathological Sciences, Kyoto Pharmaceutical University, Kyoto 607-8414, Japan
| | - Noriyuki Hatano
- Laboratory of Cellular Pharmacology, School of Pharmacy, Aichi-Gakuin University, Nagoya 464-8650, Japan
| | - Katsuhiko Muraki
- Laboratory of Cellular Pharmacology, School of Pharmacy, Aichi-Gakuin University, Nagoya 464-8650, Japan.
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Abstract
Store Operated Ca(2+) Entry (SOCE), the main Ca(2+) influx mechanism in non-excitable cells, is implicated in the immune response and has been reported to be affected in several pathologies including cancer. The basic molecular constituents of SOCE are Orai, the pore forming unit, and STIM, a multidomain protein with at least two principal functions: one is to sense the Ca(2+) content inside the lumen of the endoplasmic reticulum(ER) and the second is to activate Orai channels upon depletion of the ER. The link between Ca(2+) depletion inside the ER and Ca(2+) influx from extracellular media is through a direct association of STIM and Orai, but for this to occur, both molecules have to interact and form clusters where ER and plasma membrane (PM) are intimately apposed. In recent years a great number of components have been identified as participants in SOCE regulation, including regions of plasma membrane enriched in cholesterol and sphingolipids, the so called lipid rafts, which recruit a complex platform of specialized microdomains, which cells use to regulate spatiotemporal Ca(2+) signals.
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43
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Constantin B. Role of Scaffolding Proteins in the Regulation of TRPC-Dependent Calcium Entry. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 898:379-403. [PMID: 27161237 DOI: 10.1007/978-3-319-26974-0_16] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/06/2022]
Abstract
Plasma membrane ion channels, and in particular TRPC channels need a specific membrane environment and association with scaffolding, signaling, and cytoskeleton proteins in order to play their important functional role. The molecular composition of TRPC channels is an important factor in determining channel activation mechanisms. TRPC proteins are incorporated in macromolecular complexes including several key Ca(2 +) signaling proteins as well as proteins involved in vesicle trafficking, cytoskeletal interactions, and scaffolding. Evidence has been provided for association of TRPC with calmodulin (CaM), IP3R, PMCA, Gq/11, RhoA, and a variety of scaffolding proteins. The interaction between TRPC channels with adaptor proteins, determines their mode of regulation as well as their cellular localization and function. Adaptor proteins do not display any enzymatic activity but act as scaffold for the building of signaling complexes. The scaffolding proteins are involved in the assembling of these Ca(2+) signaling complexes, the correct sub-cellular localization of protein partners, and the regulation of the TRPC channelosome. In particular, these proteins, via their multiple protein-protein interaction motifs, can interact with various ion channels involved in the transmembrane potential, and membrane excitability. Scaffolding proteins are key components for the functional organization of TRPC channelosomes that serves as a platform regulating slow Ca(2+) entry, spatially and temporally controlled [Ca(2+)]i signals and Ca(2+) -dependent cellular functions.
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Affiliation(s)
- Bruno Constantin
- Laboratory STIM, ERL-7368 CNRS-Université de Poitiers, 1, rue Georges Bonnet, Bat. B36, Pôle Biologie-Santé, 86000, Poitiers, France.
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Ong HL, Ambudkar IS. Molecular determinants of TRPC1 regulation within ER–PM junctions. Cell Calcium 2015; 58:376-86. [DOI: 10.1016/j.ceca.2015.03.008] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2015] [Revised: 03/18/2015] [Accepted: 03/19/2015] [Indexed: 11/30/2022]
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Wie J, Kim BJ, Myeong J, Ha K, Jeong SJ, Yang D, Kim E, Jeon JH, So I. The Roles of Rasd1 small G proteins and leptin in the activation of TRPC4 transient receptor potential channels. Channels (Austin) 2015; 9:186-95. [PMID: 26083271 PMCID: PMC4594510 DOI: 10.1080/19336950.2015.1058454] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
TRPC4 is important regulators of electrical excitability in gastrointestinal myocytes, pancreatic β-cells and neurons. Much is known regarding the assembly and function of these channels including TRPC1 as a homotetramer or a heteromultimer and the roles that their interacting proteins play in controlling these events. Further, they are one of the best-studied targets of G protein-coupled receptors and growth factors in general and Gαi/o and Gαq protein coupled receptor or epidermal growth factor and leptin in particular. However, our understanding of the roles of small G proteins and leptin on TRPC4 channels is still rudimentary. We discuss potential roles for Rasd1 small G protein and leptin in channel activation in addition to their known role in cellular signaling.
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Affiliation(s)
- Jinhong Wie
- a Department of Physiology ; Seoul National University College of Medicine ; Seoul , Republic of Korea
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46
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Haase K, Pelling AE. Investigating cell mechanics with atomic force microscopy. J R Soc Interface 2015; 12:20140970. [PMID: 25589563 PMCID: PMC4345470 DOI: 10.1098/rsif.2014.0970] [Citation(s) in RCA: 216] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Accepted: 12/18/2014] [Indexed: 12/12/2022] Open
Abstract
Transmission of mechanical force is crucial for normal cell development and functioning. However, the process of mechanotransduction cannot be studied in isolation from cell mechanics. Thus, in order to understand how cells 'feel', we must first understand how they deform and recover from physical perturbations. Owing to its versatility, atomic force microscopy (AFM) has become a popular tool to study intrinsic cellular mechanical properties. Used to directly manipulate and examine whole and subcellular reactions, AFM allows for top-down and reconstitutive approaches to mechanical characterization. These studies show that the responses of cells and their components are complex, and largely depend on the magnitude and time scale of loading. In this review, we generally describe the mechanotransductive process through discussion of well-known mechanosensors. We then focus on discussion of recent examples where AFM is used to specifically probe the elastic and inelastic responses of single cells undergoing deformation. We present a brief overview of classical and current models often used to characterize observed cellular phenomena in response to force. Both simple mechanistic models and complex nonlinear models have been used to describe the observed cellular behaviours, however a unifying description of cell mechanics has not yet been resolved.
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Affiliation(s)
- Kristina Haase
- Department of Physics, Centre for Interdisciplinary NanoPhysics, MacDonald Hall, University of Ottawa, 150 Louis Pasteur, Ottawa, Ontario, Canada
| | - Andrew E Pelling
- Department of Physics, Centre for Interdisciplinary NanoPhysics, MacDonald Hall, University of Ottawa, 150 Louis Pasteur, Ottawa, Ontario, Canada Department of Biology, Gendron Hall, 30 Marie Curie, University of Ottawa, Ottawa, Ontario, Canada Institute for Science Society and Policy, Desmarais Building, 55 Laurier Ave. East, University of Ottawa, Ottawa, Ontario, Canada K1N 6N5
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47
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Guéguinou M, Gambade A, Félix R, Chantôme A, Fourbon Y, Bougnoux P, Weber G, Potier-Cartereau M, Vandier C. Lipid rafts, KCa/ClCa/Ca2+ channel complexes and EGFR signaling: Novel targets to reduce tumor development by lipids? BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2014; 1848:2603-20. [PMID: 25450343 DOI: 10.1016/j.bbamem.2014.10.036] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 10/15/2014] [Accepted: 10/22/2014] [Indexed: 12/29/2022]
Abstract
Membrane lipid rafts are distinct plasma membrane nanodomains that are enriched with cholesterol, sphingolipids and gangliosides, with occasional presence of saturated fatty acids and phospholipids containing saturated acyl chains. It is well known that they organize receptors (such as Epithelial Growth Factor Receptor), ion channels and their downstream acting molecules to regulate intracellular signaling pathways. Among them are Ca2+ signaling pathways, which are modified in tumor cells and inhibited upon membrane raft disruption. In addition to protein components, lipids from rafts also contribute to the organization and function of Ca2+ signaling microdomains. This article aims to focus on the lipid raft KCa/ClCa/Ca2+ channel complexes that regulate Ca2+ and EGFR signaling in cancer cells, and discusses the potential modification of these complexes by lipids as a novel therapeutic approach in tumor development. This article is part of a Special Issue entitled: Membrane channels and transporters in cancers.
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Affiliation(s)
- Maxime Guéguinou
- Inserm, UMR1069, Nutrition, Croissance et Cancer, Tours F-37032, France; Université François Rabelais, Tours F-37032, France
| | - Audrey Gambade
- Inserm, UMR1069, Nutrition, Croissance et Cancer, Tours F-37032, France; Université François Rabelais, Tours F-37032, France
| | - Romain Félix
- Inserm, UMR1069, Nutrition, Croissance et Cancer, Tours F-37032, France; Université François Rabelais, Tours F-37032, France
| | - Aurélie Chantôme
- Inserm, UMR1069, Nutrition, Croissance et Cancer, Tours F-37032, France; Université François Rabelais, Tours F-37032, France
| | - Yann Fourbon
- Inserm, UMR1069, Nutrition, Croissance et Cancer, Tours F-37032, France; Université François Rabelais, Tours F-37032, France
| | - Philippe Bougnoux
- Inserm, UMR1069, Nutrition, Croissance et Cancer, Tours F-37032, France; Université François Rabelais, Tours F-37032, France; Centre HS Kaplan, CHRU Tours, Tours F-37032, France
| | - Günther Weber
- Inserm, UMR1069, Nutrition, Croissance et Cancer, Tours F-37032, France; Université François Rabelais, Tours F-37032, France
| | - Marie Potier-Cartereau
- Inserm, UMR1069, Nutrition, Croissance et Cancer, Tours F-37032, France; Université François Rabelais, Tours F-37032, France
| | - Christophe Vandier
- Inserm, UMR1069, Nutrition, Croissance et Cancer, Tours F-37032, France; Université François Rabelais, Tours F-37032, France.
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Myeong J, Kwak M, Hong C, Jeon JH, So I. Identification of a membrane-targeting domain of the transient receptor potential canonical (TRPC)4 channel unrelated to its formation of a tetrameric structure. J Biol Chem 2014; 289:34990-5002. [PMID: 25349210 DOI: 10.1074/jbc.m114.584649] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Canonical transient receptor potential (TRPC) channels are Ca(2+)-permeable nonselective cation channels that are activated by a wide variety of stimuli, including G protein-coupled receptors (GPCRs). The TRPC4 channel is expressed in a punctate distribution in the membrane. To identify the regulating region of the channel trafficking to the membrane, we generated deletion mutants of the TRPC4 channel. We determined that when either region that was downstream of the 20 amino acids of the N terminus or the 700-730 amino acids was deleted, the mutants were retained in the endoplasmic reticulum. By coexpression of the wild-type TRPC4 with deletion mutants, we found that the 23-29 amino acids of the N terminus regulate a membrane trafficking. Additionally, by the fluorescence resonance energy transfer (FRET) method, we found that the regions downstream of the 99 amino acid region of the N terminus and upstream of the 730 amino acid region in the C terminus produce assembly of the TRPC4 tetramers. We inferred the candidate proteins that regulate or interact with the 23-29 domain of TRPC4.
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Affiliation(s)
- Jongyun Myeong
- From the Department of Physiology, Seoul National University College of Medicine
| | - Misun Kwak
- From the Department of Physiology, Seoul National University College of Medicine
| | - Chansik Hong
- From the Department of Physiology, Seoul National University College of Medicine
| | - Ju-Hong Jeon
- From the Department of Physiology, Seoul National University College of Medicine
| | - Insuk So
- From the Department of Physiology, Seoul National University College of Medicine
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49
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Prendergast C, Quayle J, Burdyga T, Wray S. Atherosclerosis differentially affects calcium signalling in endothelial cells from aortic arch and thoracic aorta in Apolipoprotein E knockout mice. Physiol Rep 2014; 2:2/10/e12171. [PMID: 25344475 PMCID: PMC4254096 DOI: 10.14814/phy2.12171] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Apolipoprotein‐E knockout (ApoE−/−) mice develop hypercholesterolemia and are a useful model of atherosclerosis. Hypercholesterolemia alters intracellular Ca2+ signalling in vascular endothelial cells but our understanding of these changes, especially in the early stages of the disease process, is limited. We therefore determined whether carbachol‐mediated endothelial Ca2+ signals differ in plaque‐prone aortic arch compared to plaque‐resistant thoracic aorta, of wild‐type and ApoE−/− mice, and how this is affected by age and the presence of hypercholesterolemia. The extent of plaque development was determined using en‐face staining with Sudan IV. Tissues were obtained from wild‐type and ApoE−/− mice at 10 weeks (pre‐plaques) and 24 weeks (established plaques). We found that even before development of plaques, significantly increased Ca2+ responses were observed in arch endothelial cells. Even with aging and plaque formation, ApoE−/− thoracic responses were little changed, however a significantly enhanced Ca2+ response was observed in arch, both adjacent to and away from lesions. In wild‐type mice of any age, 1–2% of cells had oscillatory Ca2+ responses. In young ApoE−/− and plaque‐free regions of older ApoE−/−, this is unchanged. However a significant increase in oscillations (~13–15%) occurred in thoracic and arch cells adjacent to lesions in older mice. Our data suggest that Ca2+ signals in endothelial cells show specific changes both before and with plaque formation, that these changes are greatest in plaque‐prone aortic arch cells, and that these changes will contribute to the reported deterioration of endothelium in atherosclerosis. We have investigated aortic endothelial cell calcium signalling changes in the Apolipoprotein E knockout mouse model of atherosclerosis. Our data show that calcium signals in endothelial cells undergo specific changes both before and with plaque formation, that these changes are greater in plaque‐prone aortic arch than in plaque‐resistant thoracic aorta, and that these changes will contribute to the reported deterioration of endothelium in atherosclerosis.
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Affiliation(s)
- Clodagh Prendergast
- Department of Cellular & Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
| | - John Quayle
- Department of Cellular & Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
| | - Theodor Burdyga
- Department of Cellular & Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
| | - Susan Wray
- Department of Cellular & Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
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Guerrero-Hernandez A, Gallegos-Gomez ML, Sanchez-Vazquez VH, Lopez-Mendez MC. Acidic intracellular Ca(2+) stores and caveolae in Ca(2+) signaling and diabetes. Cell Calcium 2014; 56:323-31. [PMID: 25182518 DOI: 10.1016/j.ceca.2014.08.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 08/07/2014] [Indexed: 12/19/2022]
Abstract
Acidic Ca(2+) stores, particularly lysosomes, are newly discovered players in the well-orchestrated arena of Ca(2+) signaling and we are at the verge of understanding how lysosomes accumulate Ca(2+) and how they release it in response to different chemical, such as NAADP, and physical signals. Additionally, it is now clear that lysosomes play a key role in autophagy, a process that allows cells to recycle components or to eliminate damaged structures to ensure cellular well-being. Moreover, lysosomes are being unraveled as hubs that coordinate both anabolism via insulin signaling and catabolism via AMPK. These acidic vesicles have close contact with the ER and there is a bidirectional movement of information between these two organelles that exquisitely regulates cell survival. Lysosomes also connect with plasma membrane where caveolae are located as specialized regions involved in Ca(2+) and insulin signaling. Alterations of all these signaling pathways are at the core of insulin resistance and diabetes.
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