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Kodakandla G, Akimzhanov AM, Boehning D. Regulatory mechanisms controlling store-operated calcium entry. Front Physiol 2023; 14:1330259. [PMID: 38169682 PMCID: PMC10758431 DOI: 10.3389/fphys.2023.1330259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 12/08/2023] [Indexed: 01/05/2024] Open
Abstract
Calcium influx through plasma membrane ion channels is crucial for many events in cellular physiology. Cell surface stimuli lead to the production of inositol 1,4,5-trisphosphate (IP3), which binds to IP3 receptors (IP3R) in the endoplasmic reticulum (ER) to release calcium pools from the ER lumen. This leads to the depletion of ER calcium pools, which has been termed store depletion. Store depletion leads to the dissociation of calcium ions from the EF-hand motif of the ER calcium sensor Stromal Interaction Molecule 1 (STIM1). This leads to a conformational change in STIM1, which helps it to interact with the plasma membrane (PM) at ER:PM junctions. At these ER:PM junctions, STIM1 binds to and activates a calcium channel known as Orai1 to form calcium release-activated calcium (CRAC) channels. Activation of Orai1 leads to calcium influx, known as store-operated calcium entry (SOCE). In addition to Orai1 and STIM1, the homologs of Orai1 and STIM1, such as Orai2/3 and STIM2, also play a crucial role in calcium homeostasis. The influx of calcium through the Orai channel activates a calcium current that has been termed the CRAC current. CRAC channels form multimers and cluster together in large macromolecular assemblies termed "puncta". How CRAC channels form puncta has been contentious since their discovery. In this review, we will outline the history of SOCE, the molecular players involved in this process, as well as the models that have been proposed to explain this critical mechanism in cellular physiology.
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Affiliation(s)
- Goutham Kodakandla
- Department of Biomedical Sciences, Cooper Medical School of Rowan University, Camden, NJ, United States
| | - Askar M. Akimzhanov
- Department of Biochemistry and Molecular Biology, McGovern Medical School, Houston, TX, United States
| | - Darren Boehning
- Department of Biomedical Sciences, Cooper Medical School of Rowan University, Camden, NJ, United States
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Kodakandla G, Akimzhanov AM, Boehning D. Regulatory mechanisms controlling store-operated calcium entry. ARXIV 2023:arXiv:2309.06907v3. [PMID: 37744466 PMCID: PMC10516112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
Calcium influx through plasma membrane ion channels is crucial for many events in cellular physiology. Cell surface stimuli lead to the production of inositol 1,4,5-trisphosphate (IP3), which binds to IP3 receptors (IP3R) in the endoplasmic reticulum (ER) to release calcium pools from the ER lumen. This leads to the depletion of ER calcium pools, which has been termed store depletion. Store depletion leads to the dissociation of calcium ions from the EF-hand motif of the ER calcium sensor Stromal Interaction Molecule 1 (STIM1). This leads to a conformational change in STIM1, which helps it to interact with the plasma membrane (PM) at ER:PM junctions. At these ER:PM junctions, STIM1 binds to and activates a calcium channel known as Orai1 to form calcium-release activated calcium (CRAC) channels. Activation of Orai1 leads to calcium influx, known as store-operated calcium entry (SOCE). In addition to Orai1 and STIM1, the homologs of Orai1 and STIM1, such as Orai2/3 and STIM2, also play a crucial role in calcium homeostasis. The influx of calcium through the Orai channel activates a calcium current that has been termed the CRAC current. CRAC channels form multimers and cluster together in large macromolecular assemblies termed "puncta". How CRAC channels form puncta has been contentious since their discovery. In this review, we will outline the history of SOCE, the molecular players involved in this process, as well as the models that have been proposed to explain this critical mechanism in cellular physiology.
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Affiliation(s)
- Goutham Kodakandla
- Department of Biomedical Sciences, Cooper Medical School of Rowan University, Camden, NJ, USA, 08103
| | - Askar M. Akimzhanov
- Department of Biochemistry and Molecular Biology, McGovern Medical School, Houston, Texas, USA, 77030
| | - Darren Boehning
- Department of Biomedical Sciences, Cooper Medical School of Rowan University, Camden, NJ, USA, 08103
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3
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Zhang Y, Wang T, Wu S, Tang L, Wang J, Yang J, Yao S, Zhang Y. Notch signaling pathway: a new target for neuropathic pain therapy. J Headache Pain 2023; 24:87. [PMID: 37454050 PMCID: PMC10349482 DOI: 10.1186/s10194-023-01616-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 06/19/2023] [Indexed: 07/18/2023] Open
Abstract
The Notch gene, a highly evolutionarily conserved gene, was discovered approximately 110 years ago and has been found to play a crucial role in the development of multicellular organisms. Notch receptors and their ligands are single-pass transmembrane proteins that typically require cellular interactions and proteolytic processing to facilitate signal transduction. Recently, mounting evidence has shown that aberrant activation of the Notch is correlated with neuropathic pain. The activation of the Notch signaling pathway can cause the activation of neuroglia and the release of pro-inflammatory factors, a key mechanism in the development of neuropathic pain. Moreover, the Notch signaling pathway may contribute to the persistence of neuropathic pain by enhancing synaptic transmission and calcium inward flow. This paper reviews the structure and activation of the Notch signaling pathway, as well as its potential mechanisms of action, to provide novel insights for future treatments of neuropathic pain.
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Affiliation(s)
- Yan Zhang
- Department of Anesthesiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, 430022, China
- Institute of Anesthesia and Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
- Key Laboratory of Anesthesiology and Resuscitation (Huazhong University of Science and Technology), Ministry of Education, Wuhan, China
| | - Tingting Wang
- Department of Anesthesiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, 430022, China
- Institute of Anesthesia and Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
- Key Laboratory of Anesthesiology and Resuscitation (Huazhong University of Science and Technology), Ministry of Education, Wuhan, China
| | - Sanlan Wu
- Department of Pharmacy, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Li Tang
- Institute of Anesthesia and Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
- Department of Pain, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, 430022, China
| | - Jia Wang
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, Institute of Health and Rehabilitation Science, Research Center for Brain-Inspired Intelligence, School of Life Science and Technology, Xi'an Jiaotong University, The Key Laboratory of Neuro-Informatics & Rehabilitation En-Gineering of Ministry of Civil Affairs, Xi'an, Shaanxi, P. R. China
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Ave, Wuhan, 430022, Hubei, China
| | - Jinghan Yang
- Department of Anesthesiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, 430022, China
- Institute of Anesthesia and Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
- Key Laboratory of Anesthesiology and Resuscitation (Huazhong University of Science and Technology), Ministry of Education, Wuhan, China
| | - Shanglong Yao
- Department of Anesthesiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, 430022, China.
- Institute of Anesthesia and Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
- Key Laboratory of Anesthesiology and Resuscitation (Huazhong University of Science and Technology), Ministry of Education, Wuhan, China.
| | - Yan Zhang
- Department of Anesthesiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, 430022, China.
- Institute of Anesthesia and Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
- Key Laboratory of Anesthesiology and Resuscitation (Huazhong University of Science and Technology), Ministry of Education, Wuhan, China.
- Department of Pain, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, 430022, China.
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Hunt EG, Andrews AM, Larsen SR, Thaxton JE. The ER-Mitochondria Interface as a Dynamic Hub for T Cell Efficacy in Solid Tumors. Front Cell Dev Biol 2022; 10:867341. [PMID: 35573704 PMCID: PMC9091306 DOI: 10.3389/fcell.2022.867341] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 03/28/2022] [Indexed: 01/09/2023] Open
Abstract
The endoplasmic reticulum (ER) is a large continuous membranous organelle that plays a central role as the hub of protein and lipid synthesis while the mitochondria is the principal location for energy production. T cells are an immune subset exhibiting robust dependence on ER and mitochondrial function based on the need for protein synthesis and secretion and metabolic dexterity associated with foreign antigen recognition and cytotoxic effector response. Intimate connections exist at mitochondrial-ER contact sites (MERCs) that serve as the structural and biochemical platforms for cellular metabolic homeostasis through regulation of fission and fusion as well as glucose, Ca2+, and lipid exchange. Work in the tumor immunotherapy field indicates that the complex interplay of nutrient deprivation and tumor antigen stimulation in the tumor microenvironment places stress on the ER and mitochondria, causing dysfunction in organellar structure and loss of metabolic homeostasis. Here, we assess prior literature that establishes how the structural interface of these two organelles is impacted by the stress of solid tumors along with recent advances in the manipulation of organelle homeostasis at MERCs in T cells. These findings provide strong evidence for increased tumor immunity using unique therapeutic avenues that recharge cellular metabolic homeostasis in T cells.
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Affiliation(s)
- Elizabeth G. Hunt
- Immunotherapy Program, Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, United States,Department of Cell Biology and Physiology, School of Medicine, University of North Carolina, Chapel Hill, NC, United States
| | - Alex M. Andrews
- Hollings Cancer Center, Charleston, SC, United States,Department of Orthopedics and Physical Medicine, Medical University of South Carolina, Charleston, SC, United States
| | | | - Jessica E. Thaxton
- Immunotherapy Program, Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, United States,Department of Cell Biology and Physiology, School of Medicine, University of North Carolina, Chapel Hill, NC, United States,*Correspondence: Jessica E. Thaxton,
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5
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Abstract
The uptake of calcium into and extrusion of calcium from the mitochondrial matrix is a fundamental biological process that has critical effects on cellular metabolism, signaling, and survival. Disruption of mitochondrial calcium (mCa2+) cycling is implicated in numerous acquired diseases such as heart failure, stroke, neurodegeneration, diabetes, and cancer, and is genetically linked to several inherited neuromuscular disorders. Understanding the mechanisms responsible for mCa2+ exchange therefore holds great promise for the treatment of these diseases. The past decade has seen the genetic identification of many of the key proteins that mediate mitochondrial calcium uptake and efflux. Here, we present an overview of the phenomenon of mCa2+ transport, and a comprehensive examination of the molecular machinery that mediates calcium flux across the inner mitochondrial membrane: the mitochondrial uniporter complex (consisting of MCU, EMRE, MICU1, MICU2, MICU3, MCUB, and MCUR1), NCLX, LETM1, the mitochondrial ryanodine receptor, and the mitochondrial permeability transition pore. We then consider the physiological implications of mCa2+ flux and evaluate how alterations in mCa2+ homeostasis contribute to human disease. This review concludes by highlighting opportunities and challenges for therapeutic intervention in pathologies characterized by aberrant mCa2+ handling and by summarizing critical unanswered questions regarding the biology of mCa2+ flux.
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Affiliation(s)
- Joanne F Garbincius
- Center for Translational Medicine, Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, United States
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Fernández-Orth J, Rolfes L, Gola L, Bittner S, Andronic J, Sukhorukov VL, Sisario D, Landgraf P, Dieterich DC, Cerina M, Smalla KH, Kähne T, Budde T, Kovac S, Ruck T, Sauer M, Meuth SG. A role for TASK2 channels in the human immunological synapse. Eur J Immunol 2020; 51:342-353. [PMID: 33169379 DOI: 10.1002/eji.201948269] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 08/30/2020] [Accepted: 11/05/2019] [Indexed: 12/29/2022]
Abstract
The immunological synapse is a transient junction that occurs when the plasma membrane of a T cell comes in close contact with an APC after recognizing a peptide from the antigen-MHC. The interaction starts when CRAC channels embedded in the T cell membrane open, flowing calcium ions into the cell. To counterbalance the ion influx and subsequent depolarization, Kv 1.3 and KCa3.1 channels are recruited to the immunological synapse, increasing the extracellular K+ concentration. These processes are crucial as they initiate gene expression that drives T cell activation and proliferation. The T cell-specific function of the K2P channel family member TASK2 channels and their role in autoimmune processes remains unclear. Using mass spectrometry analysis together with epifluorescence and super-resolution single-molecule localization microscopy, we identified TASK2 channels as novel players recruited to the immunological synapse upon stimulation. TASK2 localizes at the immunological synapse, upon stimulation with CD3 antibodies, likely interacting with these molecules. Our findings suggest that, together with Kv 1.3 and KCa3.1 channels, TASK2 channels contribute to the proper functioning of the immunological synapse, and represent an interesting treatment target for T cell-mediated autoimmune disorders.
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Affiliation(s)
| | - Leoni Rolfes
- Department of Neurology, Westfälische Wilhelms-Universität, Münster, Germany
| | - Lukas Gola
- Department of Neurology, Westfälische Wilhelms-Universität, Münster, Germany
| | - Stefan Bittner
- Department of Neurology, University Medical Center, Johannes Gutenberg-University, Mainz, Germany
| | - Joseph Andronic
- Department of Biotechnology and Biophysics, Biocenter, Julius-Maximilians-University Würzburg, Würzburg, Germany
| | - Vladimir L Sukhorukov
- Department of Biotechnology and Biophysics, Biocenter, Julius-Maximilians-University Würzburg, Würzburg, Germany
| | - Dmitri Sisario
- Department of Biotechnology and Biophysics, Biocenter, Julius-Maximilians-University Würzburg, Würzburg, Germany
| | - Peter Landgraf
- Neural Plasticity and Communication, Institute for Pharmacology and Toxicology, Otto-von-Guericke-University, Magdeburg, Germany
| | - Daniela C Dieterich
- Neural Plasticity and Communication, Institute for Pharmacology and Toxicology, Otto-von-Guericke-University, Magdeburg, Germany.,Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany
| | - Manuela Cerina
- Department of Neurology, Westfälische Wilhelms-Universität, Münster, Germany
| | - Karl-Heinz Smalla
- Special Lab Molecular Biological Techniques, Leibniz Institute for Neurobiology, Magdeburg, Germany
| | - Thilo Kähne
- Institute of Experimental Internal Medicine, Medical Faculty, Otto-von-Guericke-University, Magdeburg, Germany
| | - Thomas Budde
- Institute of Physiology I, Westfälische Wilhelms-Universität, Münster, Germany
| | - Stjepana Kovac
- Department of Neurology, Westfälische Wilhelms-Universität, Münster, Germany
| | - Tobias Ruck
- Department of Neurology, Westfälische Wilhelms-Universität, Münster, Germany
| | - Markus Sauer
- Department of Biotechnology and Biophysics, Biocenter, Julius-Maximilians-University Würzburg, Würzburg, Germany
| | - Sven G Meuth
- Department of Neurology, Westfälische Wilhelms-Universität, Münster, Germany
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Si H, Wang J, Meininger CJ, Peng X, Zawieja DC, Zhang SL. Ca 2+ release-activated Ca 2+ channels are responsible for histamine-induced Ca 2+ entry, permeability increase, and interleukin synthesis in lymphatic endothelial cells. Am J Physiol Heart Circ Physiol 2020; 318:H1283-H1295. [PMID: 32275470 DOI: 10.1152/ajpheart.00544.2019] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The lymphatic functions in maintaining lymph transport, and immune surveillance can be impaired by infections and inflammation, thereby causing debilitating disorders, such as lymphedema and inflammatory bowel disease. Histamine is a key inflammatory mediator known to trigger vasodilation and vessel hyperpermeability upon binding to its receptors and evoking intracellular Ca2+ ([Ca2+]i) dynamics for downstream signal transductions. However, the exact molecular mechanisms beneath the [Ca2+]i dynamics and the downstream cellular effects have not been elucidated in the lymphatic system. Here, we show that Ca2+ release-activated Ca2+ (CRAC) channels, formed by Orai1 and stromal interaction molecule 1 (STIM1) proteins, are required for the histamine-elicited Ca2+ signaling in human dermal lymphatic endothelial cells (HDLECs). Blockers or antagonists against CRAC channels, phospholipase C, and H1R receptors can all significantly diminish the histamine-evoked [Ca2+]i dynamics in lymphatic endothelial cells (LECs), while short interfering RNA-mediated knockdown of endogenous Orai1 or STIM1 also abolished the Ca2+ entry upon histamine stimulation in LECs. Furthermore, we find that histamine compromises the lymphatic endothelial barrier function by increasing the intercellular permeability and disrupting vascular endothelial-cadherin integrity, which is remarkably attenuated by CRAC channel blockers. Additionally, the upregulated expression of inflammatory cytokines, IL-6 and IL-8, after histamine stimulation was abolished by silencing Orai1 or STIM1 with RNAi in LECs. Taken together, our data demonstrated the essential role of CRAC channels in mediating the [Ca2+]i signaling and downstream endothelial barrier and inflammatory functions induced by histamine in the LECs, suggesting a promising potential to relieve histamine-triggered vascular leakage and inflammatory disorders in the lymphatics by targeting CRAC channel functions.
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Affiliation(s)
- Hongjiang Si
- Department of Medical Physiology, College of Medicine, Texas A&M University Health Science Center, Bryan, Texas
| | - Jian Wang
- Department of Medical Physiology, College of Medicine, Texas A&M University Health Science Center, Bryan, Texas
| | - Cynthia J Meininger
- Department of Medical Physiology, College of Medicine, Texas A&M University Health Science Center, Bryan, Texas
| | - Xu Peng
- Department of Medical Physiology, College of Medicine, Texas A&M University Health Science Center, Bryan, Texas
| | - David C Zawieja
- Department of Medical Physiology, College of Medicine, Texas A&M University Health Science Center, Bryan, Texas
| | - Shenyuan L Zhang
- Department of Medical Physiology, College of Medicine, Texas A&M University Health Science Center, Bryan, Texas
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Okubo Y, Iino M, Hirose K. Store-operated Ca 2+ entry-dependent Ca 2+ refilling in the endoplasmic reticulum in astrocytes. Biochem Biophys Res Commun 2019; 522:1003-1008. [PMID: 31812243 DOI: 10.1016/j.bbrc.2019.12.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 12/01/2019] [Indexed: 12/11/2022]
Abstract
Astrocytes regulate various brain functions, for which Ca2+ release from the endoplasmic reticulum (ER) often play crucial roles. Because astrocytic ER Ca2+ release is robust and frequent, the ER Ca2+ refilling mechanism should be critical for ongoing Ca2+ signaling in astrocytes. In this study, we focused on the putative functional significance of store-operated Ca2+ entry (SOCE) in ER Ca2+ refilling. We expressed the ER luminal Ca2+ indicator G-CEPIA1er in astrocytes in acute cortical slices to directly monitor the decrease and recovery of ER Ca2+ concentration upon spontaneous or norepinephrine-induced Ca2+ release. Inhibition of SOCE significantly slowed the recovery of ER Ca2+ concentration after Ca2+ release in astrocytes. This delayed recovery resulted in a prolonged decrease in the ER Ca2+ content in astrocytes with periodic spontaneous Ca2+ release, followed by the attenuation of cytosolic Ca2+ responses upon Ca2+ release. Therefore, our results provide direct evidence for the physiological significance of SOCE in ER Ca2+ refilling after ER Ca2+ release.
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Affiliation(s)
- Yohei Okubo
- Department of Pharmacology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 133-0033, Japan.
| | - Masamitsu Iino
- Division of Cellular and Molecular Pharmacology, Nihon University School of Medicine, 30-1 Oyaguchi Kamicho, Itabashi-ku, Tokyo, 173-8610, Japan
| | - Kenzo Hirose
- Department of Pharmacology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 133-0033, Japan
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Tiapko O, Groschner K. TRPC3 as a Target of Novel Therapeutic Interventions. Cells 2018; 7:cells7070083. [PMID: 30037143 PMCID: PMC6071100 DOI: 10.3390/cells7070083] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2018] [Revised: 07/18/2018] [Accepted: 07/20/2018] [Indexed: 01/25/2023] Open
Abstract
TRPC3 is one of the classical members of the mammalian transient receptor potential (TRP) superfamily of ion channels. TRPC3 is a molecule with intriguing sensory features including the direct recognition of and activation by diacylglycerols (DAG). Although TRPC3 channels are ubiquitously expressed, they appear to control functions of the cardiovascular system and the brain in a highly specific manner. Moreover, a role of TRPC3 in immunity, cancer, and tissue remodeling has been proposed, generating much interest in TRPC3 as a target for pharmacological intervention. Advances in the understanding of molecular architecture and structure-function relations of TRPC3 have been the foundations for novel therapeutic approaches, such as photopharmacology and optochemical genetics of TRPC3. This review provides an account of advances in therapeutic targeting of TRPC3 channels.
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Affiliation(s)
- Oleksandra Tiapko
- Gottfried-Schatz-Research-Center-Biophysics, Medical University of Graz, Neue Stiftingtalstrasse 6/D04, 8010 Graz, Austria.
| | - Klaus Groschner
- Gottfried-Schatz-Research-Center-Biophysics, Medical University of Graz, Neue Stiftingtalstrasse 6/D04, 8010 Graz, Austria.
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10
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Zierler S, Hampe S, Nadolni W. TRPM channels as potential therapeutic targets against pro-inflammatory diseases. Cell Calcium 2017; 67:105-115. [PMID: 28549569 DOI: 10.1016/j.ceca.2017.05.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 05/02/2017] [Indexed: 02/08/2023]
Abstract
The immune system protects our body against foreign pathogens. However, if it overshoots or turns against itself, pro-inflammatory diseases, such as rheumatoid arthritis, inflammatory bowel disease, or diabetes develop. Ions, the most basic signaling molecules, shape intracellular signaling cascades resulting in immune cell activation and subsequent immune responses. Mutations in ion channels required for calcium signaling result in human immunodeficiencies and highlight those ion channels as valued targets for therapies against pro-inflammatory diseases. Signaling pathways regulated by melastatin-like transient receptor potential (TRPM) cation channels also play crucial roles in calcium signaling and leukocyte physiology, affecting phagocytosis, degranulation, chemokine and cytokine expression, chemotaxis and invasion, as well as lymphocyte development and proliferation. Therefore, this review discusses their regulation, possible interactions and whether they can be exploited as targets for therapeutic approaches to pro-inflammatory diseases.
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Affiliation(s)
- Susanna Zierler
- Walther Straub Institute of Pharmacology and Toxicology, LMU Munich, Germany.
| | - Sarah Hampe
- Walther Straub Institute of Pharmacology and Toxicology, LMU Munich, Germany
| | - Wiebke Nadolni
- Walther Straub Institute of Pharmacology and Toxicology, LMU Munich, Germany
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11
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Sun C, Jiang M, Zhang L, Yang J, Zhang G, Du B, Ren Y, Li X, Yao J. Cycloastragenol mediates activation and proliferation suppression in concanavalin A-induced mouse lymphocyte pan-activation model. Immunopharmacol Immunotoxicol 2017; 39:131-139. [DOI: 10.1080/08923973.2017.1300170] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Chenghong Sun
- Linyi Key Laboratory for Immunopharmacology and Immunotoxicology of Natural Medicine, Lunan Pharmaceutical Group Corporation, Linyi, China
- State Key Laboratory of Generic Pharmaceutical Technology for Chinese Medicine, Lunan Pharmaceutical Group Corporation, Linyi, China
- Center for New Drug Pharmacology, Lunan Pharmaceutical Group Corporation, Linyi, PR China
| | - Mingmin Jiang
- Linyi Key Laboratory for Immunopharmacology and Immunotoxicology of Natural Medicine, Lunan Pharmaceutical Group Corporation, Linyi, China
- State Key Laboratory of Generic Pharmaceutical Technology for Chinese Medicine, Lunan Pharmaceutical Group Corporation, Linyi, China
- Center for New Drug Pharmacology, Lunan Pharmaceutical Group Corporation, Linyi, PR China
| | - Li Zhang
- State Key Laboratory of Generic Pharmaceutical Technology for Chinese Medicine, Lunan Pharmaceutical Group Corporation, Linyi, China
| | - Jian Yang
- Linyi Key Laboratory for Immunopharmacology and Immunotoxicology of Natural Medicine, Lunan Pharmaceutical Group Corporation, Linyi, China
- State Key Laboratory of Generic Pharmaceutical Technology for Chinese Medicine, Lunan Pharmaceutical Group Corporation, Linyi, China
- Center for New Drug Pharmacology, Lunan Pharmaceutical Group Corporation, Linyi, PR China
| | - Guimin Zhang
- State Key Laboratory of Generic Pharmaceutical Technology for Chinese Medicine, Lunan Pharmaceutical Group Corporation, Linyi, China
| | - Bingyuan Du
- Linyi Key Laboratory for Immunopharmacology and Immunotoxicology of Natural Medicine, Lunan Pharmaceutical Group Corporation, Linyi, China
- State Key Laboratory of Generic Pharmaceutical Technology for Chinese Medicine, Lunan Pharmaceutical Group Corporation, Linyi, China
- Center for New Drug Pharmacology, Lunan Pharmaceutical Group Corporation, Linyi, PR China
| | - Yushan Ren
- Linyi Key Laboratory for Immunopharmacology and Immunotoxicology of Natural Medicine, Lunan Pharmaceutical Group Corporation, Linyi, China
- State Key Laboratory of Generic Pharmaceutical Technology for Chinese Medicine, Lunan Pharmaceutical Group Corporation, Linyi, China
- Center for New Drug Pharmacology, Lunan Pharmaceutical Group Corporation, Linyi, PR China
| | - Xin Li
- Linyi Key Laboratory for Immunopharmacology and Immunotoxicology of Natural Medicine, Lunan Pharmaceutical Group Corporation, Linyi, China
- State Key Laboratory of Generic Pharmaceutical Technology for Chinese Medicine, Lunan Pharmaceutical Group Corporation, Linyi, China
- Center for New Drug Pharmacology, Lunan Pharmaceutical Group Corporation, Linyi, PR China
| | - Jingchun Yao
- Linyi Key Laboratory for Immunopharmacology and Immunotoxicology of Natural Medicine, Lunan Pharmaceutical Group Corporation, Linyi, China
- State Key Laboratory of Generic Pharmaceutical Technology for Chinese Medicine, Lunan Pharmaceutical Group Corporation, Linyi, China
- Center for New Drug Pharmacology, Lunan Pharmaceutical Group Corporation, Linyi, PR China
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12
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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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13
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Mishra S, Tripathi R, Singh S. Crosstalk of proteins, miRNAs involved in metastatic and epithelial–mesenchymal transition pathways. FRONTIERS IN LIFE SCIENCE 2016. [DOI: 10.1080/21553769.2016.1256843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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14
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Abstract
Store-operated calcium channels (SOCs) are a major pathway for calcium signaling in virtually all metozoan cells and serve a wide variety of functions ranging from gene expression, motility, and secretion to tissue and organ development and the immune response. SOCs are activated by the depletion of Ca(2+) from the endoplasmic reticulum (ER), triggered physiologically through stimulation of a diverse set of surface receptors. Over 15 years after the first characterization of SOCs through electrophysiology, the identification of the STIM proteins as ER Ca(2+) sensors and the Orai proteins as store-operated channels has enabled rapid progress in understanding the unique mechanism of store-operate calcium entry (SOCE). Depletion of Ca(2+) from the ER causes STIM to accumulate at ER-plasma membrane (PM) junctions where it traps and activates Orai channels diffusing in the closely apposed PM. Mutagenesis studies combined with recent structural insights about STIM and Orai proteins are now beginning to reveal the molecular underpinnings of these choreographic events. This review describes the major experimental advances underlying our current understanding of how ER Ca(2+) depletion is coupled to the activation of SOCs. Particular emphasis is placed on the molecular mechanisms of STIM and Orai activation, Orai channel properties, modulation of STIM and Orai function, pharmacological inhibitors of SOCE, and the functions of STIM and Orai in physiology and disease.
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Affiliation(s)
- Murali Prakriya
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois; and Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, California
| | - Richard S Lewis
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois; and Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, California
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15
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Zheng L, Zinn V, Lefkelidou A, Taqi N, Chatzistavrou X, Balam T, Nervina J, Papagerakis S, Papagerakis P. Orai1 expression pattern in tooth and craniofacial ectodermal tissues and potential functions during ameloblast differentiation. Dev Dyn 2015; 244:1249-58. [PMID: 26178077 DOI: 10.1002/dvdy.24307] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Revised: 06/24/2015] [Accepted: 07/01/2015] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND Orai1 is a plasma membrane protein that forms the pore of the calcium release activated calcium channel. Humans with mutated Orai1 present with hereditary combined immunodeficiency, congenital myopathy and anhidrotic ectodermal dysplasia. Consistent with the ectodermal dysplasia phenotype, enamel formation and mineralization is also abnormal in Orai1 deficient patients. The expression pattern and potential functions of Orai1 in enamel formation remains unclear. To contribute toward understanding the role of Orai1 in amelogenesis we characterized ORAI1 protein developmental pattern in comparison with other ectodermal organs. We also examined the effects of Orai1 down-regulation in ameloblast cell proliferation and differentiation. RESULTS Our data show strong expression of ORAI1 protein during the ameloblast secretory stage, which weans at the end of the maturation stage. In salivary glands, ORAI1 is expressed mainly in acini cells. ORAI1 expression is also found in hair follicle and oral epithelium. Knockdown of Orai1 expression decreases cell proliferation and results in RNA expression levels changes of key ameloblast genes regulating enamel thickness and mineralization. CONCLUSIONS This study provides insights in the anhidrotic ectodermal dysplasia phenotype due to Orai1 mutation and highlights the importance of calcium signaling in controlling ameloblast differentiation and maturation during tooth development.
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Affiliation(s)
- Li Zheng
- Department of Orthodontics and Pediatric Dentistry, School of Dentistry, University of Michigan, Ann Arbor, Michigan.,Department of Otolaryngology, School of Medicine, University of Michigan, Ann Arbor, Michigan
| | - Vina Zinn
- Department of Orthodontics and Pediatric Dentistry, School of Dentistry, University of Michigan, Ann Arbor, Michigan
| | - Anna Lefkelidou
- Department of Orthodontics and Pediatric Dentistry, School of Dentistry, University of Michigan, Ann Arbor, Michigan
| | - Nawar Taqi
- Department of Orthodontics and Pediatric Dentistry, School of Dentistry, University of Michigan, Ann Arbor, Michigan
| | - Xanthippi Chatzistavrou
- Department of Orthodontics and Pediatric Dentistry, School of Dentistry, University of Michigan, Ann Arbor, Michigan
| | - Tarek Balam
- Department of Orthodontics and Pediatric Dentistry, School of Dentistry, University of Michigan, Ann Arbor, Michigan
| | - Jeanne Nervina
- Department of Orthodontics and Pediatric Dentistry, School of Dentistry, University of Michigan, Ann Arbor, Michigan
| | - Silvana Papagerakis
- Department of Otolaryngology, School of Medicine, University of Michigan, Ann Arbor, Michigan.,Department of Periodontology and Oral Medicine, School of Dentistry, University of Michigan, Ann Arbor, Michigan
| | - Petros Papagerakis
- Department of Orthodontics and Pediatric Dentistry, School of Dentistry, University of Michigan, Ann Arbor, Michigan.,Center for Organogenesis, School of Medicine, University of Michigan, Ann Arbor, Michigan.,Center for Computational Medicine and Bioinformatics, School of Medicine, University of Michigan, Ann Arbor, Michigan
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16
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Davis LC, Platt FM, Galione A. Preferential Coupling of the NAADP Pathway to Exocytosis in T-Cells. MESSENGER (LOS ANGELES, CALIF. : PRINT) 2015; 4:53-66. [PMID: 27330870 PMCID: PMC4910867 DOI: 10.1166/msr.2015.1040] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
A cytotoxic T-lymphocyte (CTL) kills an infected or tumorigenic cell by Ca2+-dependent exocytosis of cytolytic granules at the immunological synapse formed between the two cells. However, these granules are more than reservoirs of secretory cytolytic proteins but may also serve as unique Ca2+ signaling hubs that autonomously generate their own signals for exocytosis. This review discusses a selective role for the Ca2+-mobilizing messenger, nicotinic acid adenine dinucleotide phosphate (NAADP) and its molecular targets, two-pore channels (TPCs), in stimulating exocytosis. Given that TPCs reside on the exocytotic granules themselves, these vesicles generate as well as respond to NAADP-dependent Ca2+ signals, which may have wider implications for stimulus-secretion coupling, vesicular fusion, and patho-physiology.
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Affiliation(s)
- Lianne C. Davis
- Department of Pharmacology, University of Oxford, Oxford, OX1 3QT, UK
| | - Frances M. Platt
- Department of Pharmacology, University of Oxford, Oxford, OX1 3QT, UK
| | - Antony Galione
- Department of Pharmacology, University of Oxford, Oxford, OX1 3QT, UK
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17
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Nohara LL, Stanwood SR, Omilusik KD, Jefferies WA. Tweeters, Woofers and Horns: The Complex Orchestration of Calcium Currents in T Lymphocytes. Front Immunol 2015; 6:234. [PMID: 26052328 PMCID: PMC4440397 DOI: 10.3389/fimmu.2015.00234] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2015] [Accepted: 04/30/2015] [Indexed: 11/28/2022] Open
Abstract
Elevation of intracellular calcium ion (Ca2+) levels is a vital event that regulates T lymphocyte homeostasis, activation, proliferation, differentiation, and apoptosis. The mechanisms that regulate intracellular Ca2+ signaling in lymphocytes involve tightly controlled concinnity of multiple ion channels, membrane receptors, and signaling molecules. T cell receptor (TCR) engagement results in depletion of endoplasmic reticulum (ER) Ca2+ stores and subsequent sustained influx of extracellular Ca2+ through Ca2+ release-activated Ca2+ (CRAC) channels in the plasma membrane. This process termed store-operated Ca2+ entry (SOCE) involves the ER Ca2+ sensing molecule, STIM1, and a pore-forming plasma membrane protein, ORAI1. However, several other important Ca2+ channels that are instrumental in T cell function also exist. In this review, we discuss the role of additional Ca2+ channel families expressed on the plasma membrane of T cells that likely contribute to Ca2+ influx following TCR engagement, which include the TRP channels, the NMDA receptors, the P2X receptors, and the IP3 receptors, with a focus on the voltage-dependent Ca2+ (CaV) channels.
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Affiliation(s)
- Lilian L Nohara
- Michael Smith Laboratories, University of British Columbia , Vancouver, BC , Canada ; Department of Microbiology and Immunology, University of British Columbia , Vancouver, BC , Canada
| | - Shawna R Stanwood
- Michael Smith Laboratories, University of British Columbia , Vancouver, BC , Canada ; Department of Microbiology and Immunology, University of British Columbia , Vancouver, BC , Canada
| | - Kyla D Omilusik
- Michael Smith Laboratories, University of British Columbia , Vancouver, BC , Canada ; Department of Microbiology and Immunology, University of British Columbia , Vancouver, BC , Canada
| | - Wilfred A Jefferies
- Michael Smith Laboratories, University of British Columbia , Vancouver, BC , Canada ; Department of Microbiology and Immunology, University of British Columbia , Vancouver, BC , Canada ; Centre for Blood Research, University of British Columbia , Vancouver, BC , Canada ; The Djavad Mowafaghian Centre for Brain Health, University of British Columbia , Vancouver, BC , Canada ; Department of Medical Genetics, University of British Columbia , Vancouver, BC , Canada ; Department of Zoology, University of British Columbia , Vancouver, BC , Canada
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18
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Moccia F, Zuccolo E, Soda T, Tanzi F, Guerra G, Mapelli L, Lodola F, D'Angelo E. Stim and Orai proteins in neuronal Ca(2+) signaling and excitability. Front Cell Neurosci 2015; 9:153. [PMID: 25964739 PMCID: PMC4408853 DOI: 10.3389/fncel.2015.00153] [Citation(s) in RCA: 125] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Accepted: 04/03/2015] [Indexed: 02/01/2023] Open
Abstract
Stim1 and Orai1 are ubiquitous proteins that have long been known to mediate Ca2+ release-activated Ca2+ (CRAC) current (ICRAC) and store-operated Ca2+ entry (SOCE) only in non-excitable cells. SOCE is activated following the depletion of the endogenous Ca2+ stores, which are mainly located within the endoplasmic reticulum (ER), to replete the intracellular Ca2+ reservoir and engage specific Ca2+-dependent processes, such as proliferation, migration, cytoskeletal remodeling, and gene expression. Their paralogs, Stim2, Orai2 and Orai3, support SOCE in heterologous expression systems, but their physiological role is still obscure. Ca2+ inflow in neurons has long been exclusively ascribed to voltage-operated and receptor-operated channels. Nevertheless, recent work has unveiled that Stim1–2 and Orai1-2, but not Orai3, proteins are also expressed and mediate SOCE in neurons. Herein, we survey current knowledge about the neuronal distribution of Stim and Orai proteins in rodent and human brains; we further discuss that Orai2 is the main pore-forming subunit of CRAC channels in central neurons, in which it may be activated by either Stim1 or Stim2 depending on species, brain region and physiological stimuli. We examine the functions regulated by SOCE in neurons, where this pathway is activated under resting conditions to refill the ER, control spinogenesis and regulate gene transcription. Besides, we highlighted the possibility that SOCE also controls neuronal excitation and regulate synaptic plasticity. Finally, we evaluate the involvement of Stim and Orai proteins in severe neurodegenerative and neurological disorders, such as Alzheimer’s disease and epilepsy.
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Affiliation(s)
- Francesco Moccia
- Laboratory of General Physiology, Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia Pavia, Italy
| | - Estella Zuccolo
- Laboratory of General Physiology, Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia Pavia, Italy
| | - Teresa Soda
- Neurophysiology Unit, Department of Brain and Behavioral Sciences, University of Pavia Pavia, Italy
| | - Franco Tanzi
- Laboratory of General Physiology, Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia Pavia, Italy
| | - Germano Guerra
- Department of Medicine and Health Sciences, University of Molise Campobasso, Italy
| | - Lisa Mapelli
- Neurophysiology Unit, Department of Brain and Behavioral Sciences, University of Pavia Pavia, Italy ; Museo Storico della Fisica e Centro di Studi e Ricerche Enrico Fermi Roma, Italy
| | - Francesco Lodola
- Laboratory of Molecular Cardiology, IRCCS Fondazione Salvatore Maugeri Pavia, Italy
| | - Egidio D'Angelo
- Neurophysiology Unit, Department of Brain and Behavioral Sciences, University of Pavia Pavia, Italy ; Brain Connectivity Center, C. Mondino National Neurological Institute, Fondazione IRCCS Policlinico San Matteo Pavia Pavia, Italy
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19
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Huang K, Kiefer C, Kamal A. Novel role for NFAT3 in ERK-mediated regulation of CXCR4. PLoS One 2014; 9:e115249. [PMID: 25514788 PMCID: PMC4267837 DOI: 10.1371/journal.pone.0115249] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Accepted: 11/20/2014] [Indexed: 01/09/2023] Open
Abstract
The G-protein coupled chemokine (C-X-C motif) receptor CXCR4 is linked to cancer, HIV, and WHIM (Warts, Hypogammaglobulinemia, Infections, and Myelokathexis) syndrome. While CXCR4 is reported to be overexpressed in multiple human cancer types and many hematological cancer cell lines, we have observed poor in vitro cell surface expression of CXCR4 in many solid tumor cell lines. We explore further the possible factors and pathways involved in regulating CXCR4 expression. Here, we showed that MEK-ERK signaling pathway and NFAT3 transcriptional factor plays a novel role in regulating CXCR4 expression. When cultured as 3D spheroids, HeyA8 ovarian tumor cells showed a dramatic increase in surface CXCR4 protein levels as well as mRNA transcripts. Furthermore, HeyA8 3D spheroids showed a decrease in phospho-ERK levels when compared to adherent cells. The treatment of adherent HeyA8 cells with an inhibitor of the MEK-ERK pathway, U0126, resulted in a significant increase in surface CXCR4 expression. Additional investigation using the PCR array assay comparing adherent to 3D spheroid showed a wide range of transcription factors being up-regulated, most notably a > 20 fold increase in NFAT3 transcription factor mRNA. Finally, chromatin immunoprecipitation (ChIP) analysis showed that direct binding of NFAT3 on the CXCR4 promoter corresponds to increased CXCR4 expression in HeyA8 ovarian cell line. Taken together, our results suggest that high phospho-ERK levels and NFAT3 expression plays a novel role in regulating CXCR4 expression.
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Affiliation(s)
- Keven Huang
- Department of Oncology Research, MedImmune, Gaithersburg, Maryland, United States of America
- * E-mail:
| | - Christine Kiefer
- Department of Antibody Discovery and Protein Engineering, MedImmune, Gaithersburg, Maryland, United States of America
| | - Adeela Kamal
- Department of Oncology Research, MedImmune, Gaithersburg, Maryland, United States of America
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20
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Fracchia KM, Pai CY, Walsh CM. Modulation of T Cell Metabolism and Function through Calcium Signaling. Front Immunol 2013; 4:324. [PMID: 24133495 PMCID: PMC3795426 DOI: 10.3389/fimmu.2013.00324] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Accepted: 09/24/2013] [Indexed: 01/08/2023] Open
Abstract
As a vital second messenger in the activation of lymphocytes, the divalent cation Ca(2+) plays numerous roles in adaptive immune responses. Importantly, Ca(2+) signaling is essential for T cell activation, tolerance of self-antigens, and homeostasis. Supporting the essential role of Ca(2+) signaling in T cell biology, the Ca(2+) regulated protein phosphatase calcineurin is a key target of pharmacologic inhibition for preventing allograft rejection and for autoimmune therapy. Recent studies have highlighted the unique role of Stim1 and Orai1/2 proteins in the regulation of store-operated/calcium release activated calcium (CRAC) channels in the context of T cells. While Ca(2+) is known to modulate T cell activation via effects on calcineurin and its target, nuclear factor of activated T cells (NFAT), this second messenger also regulates other pathways, including protein kinase C, calmodulin kinases, and cytoskeletal proteins. Ca(2+) also modulates the unique metabolic changes that occur during in distinct T cell stages and subsets. Herein, we discuss the means by which Ca(2+) mobilization modulates cellular metabolism following T cell receptor ligation. Further, we highlight the crosstalk between mitochondrial metabolism, reactive oxygen species (ROS) generation, and CRAC channel activity. As a target of mitochondrial ROS and Ca(2+) regulation, we describe the involvement of the serine/threonine kinase DRAK2 in the context of these processes. Given the important roles for Ca(2+) dependent signaling and cellular metabolism in adaptive immune responses, the crosstalk between these pathways is likely to be important for the regulation of T cell activation, tolerance, and homeostasis.
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Affiliation(s)
- Kelley M Fracchia
- Department of Molecular Biology and Biochemistry, The Institute for Immunology, University of California Irvine , Irvine, CA , USA
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21
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Badou A, Jha MK, Matza D, Flavell RA. Emerging roles of L-type voltage-gated and other calcium channels in T lymphocytes. Front Immunol 2013; 4:243. [PMID: 24009608 PMCID: PMC3757574 DOI: 10.3389/fimmu.2013.00243] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Accepted: 08/05/2013] [Indexed: 11/16/2022] Open
Abstract
In T lymphocytes, calcium ion controls a variety of biological processes including development, survival, proliferation, and effector functions. These distinct and specific roles are regulated by different calcium signals, which are generated by various plasma membrane calcium channels. The repertoire of calcium-conducting proteins in T lymphocytes includes store-operated CRAC channels, transient receptor potential channels, P2X channels, and L-type voltage-gated calcium (Cav1) channels. In this paper, we will focus mainly on the role of the Cav1 channels found expressed by T lymphocytes, where these channels appear to operate in a T cell receptor stimulation-dependent and voltage sensor independent manner. We will review their expression profile at various differentiation stages of CD4 and CD8 T lymphocytes. Then, we will present crucial genetic evidence in favor of a role of these Cav1 channels and related regulatory proteins in both CD4 and CD8 T cell functions such as proliferation, survival, cytokine production, and cytolysis. Finally, we will provide evidence and speculate on how these voltage-gated channels might function in the T lymphocyte, a non-excitable cell.
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Affiliation(s)
- Abdallah Badou
- Equipe de recherche Environnement et Santé, Faculté Polydisciplinaire de Safi, Université Cadi Ayyad , Safi , Morocco
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22
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Jairaman A, Prakriya M. Molecular pharmacology of store-operated CRAC channels. Channels (Austin) 2013; 7:402-14. [PMID: 23807116 DOI: 10.4161/chan.25292] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Calcium influx through store-operated Ca(2+) release-activated Ca(2+) channels (CRAC channels) is a well-defined mechanism of generating cellular Ca(2+) elevations that regulates many functions including gene expression, exocytosis and cell proliferation. The identifications of the ER Ca(2+) sensing proteins, STIM1-2 and the CRAC channel proteins, Orai1-3, have led to improved understanding of the physiological roles and the activation mechanism of CRAC channels. Defects in CRAC channel function are associated with serious human diseases such as immunodeficiency and auto-immunity. In this review, we discuss several pharmacological modulators of CRAC channels, focusing specifically on the molecular mechanism of drug action and their utility in illuminating the mechanism of CRAC channel operation and their physiological roles in different cells.
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Affiliation(s)
- Amit Jairaman
- Department of Molecular Pharmacology and Biological Chemistry; Northwestern University, Feinberg School of Medicine; Chicago, IL USA
| | - Murali Prakriya
- Department of Molecular Pharmacology and Biological Chemistry; Northwestern University, Feinberg School of Medicine; Chicago, IL USA
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23
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Joseph N, Reicher B, Barda-Saad M. The calcium feedback loop and T cell activation: how cytoskeleton networks control intracellular calcium flux. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1838:557-68. [PMID: 23860253 DOI: 10.1016/j.bbamem.2013.07.009] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Revised: 06/30/2013] [Accepted: 07/08/2013] [Indexed: 12/31/2022]
Abstract
During T cell activation, the engagement of a T cell with an antigen-presenting cell (APC) results in rapid cytoskeletal rearrangements and a dramatic increase of intracellular calcium (Ca(2+)) concentration, downstream to T cell antigen receptor (TCR) ligation. These events facilitate the organization of an immunological synapse (IS), which supports the redistribution of receptors, signaling molecules and organelles towards the T cell-APC interface to induce downstream signaling events, ultimately supporting T cell effector functions. Thus, Ca(2+) signaling and cytoskeleton rearrangements are essential for T cell activation and T cell-dependent immune response. Rapid release of Ca(2+) from intracellular stores, e.g. the endoplasmic reticulum (ER), triggers the opening of Ca(2+) release-activated Ca(2+) (CRAC) channels, residing in the plasma membrane. These channels facilitate a sustained influx of extracellular Ca(2+) across the plasma membrane in a process termed store-operated Ca(2+) entry (SOCE). Because CRAC channels are themselves inhibited by Ca(2+) ions, additional factors are suggested to enable the sustained Ca(2+) influx required for T cell function. Among these factors, we focus here on the contribution of the actin and microtubule cytoskeleton. The TCR-mediated increase in intracellular Ca(2+) evokes a rapid cytoskeleton-dependent polarization, which involves actin cytoskeleton rearrangements and microtubule-organizing center (MTOC) reorientation. Here, we review the molecular mechanisms of Ca(2+) flux and cytoskeletal rearrangements, and further describe the way by which the cytoskeletal networks feedback to Ca(2+) signaling by controlling the spatial and temporal distribution of Ca(2+) sources and sinks, modulating TCR-dependent Ca(2+) signals, which are required for an appropriate T cell response. This article is part of a Special Issue entitled: Reciprocal influences between cell cytoskeleton and membrane channels, receptors and transporters. Guest Editor: Jean Claude Hervé.
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Affiliation(s)
- Noah Joseph
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Barak Reicher
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Mira Barda-Saad
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel.
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Omilusik KD, Nohara LL, Stanwood S, Jefferies WA. Weft, warp, and weave: the intricate tapestry of calcium channels regulating T lymphocyte function. Front Immunol 2013; 4:164. [PMID: 23805141 PMCID: PMC3690356 DOI: 10.3389/fimmu.2013.00164] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Accepted: 06/11/2013] [Indexed: 12/20/2022] Open
Abstract
Calcium (Ca(2+)) is a universal second messenger important for T lymphocyte homeostasis, activation, proliferation, differentiation, and apoptosis. The events surrounding Ca(2+) mobilization in lymphocytes are tightly regulated and involve the coordination of diverse ion channels, membrane receptors, and signaling molecules. A mechanism termed store-operated Ca(2+) entry (SOCE), causes depletion of endoplasmic reticulum (ER) Ca(2+) stores following T cell receptor (TCR) engagement and triggers a sustained influx of extracellular Ca(2+) through Ca(2+) release-activated Ca(2+) (CRAC) channels in the plasma membrane. The ER Ca(2+) sensing molecule, stromal interaction molecule 1 (STIM1), and a pore-forming plasma membrane protein, ORAI1, have been identified as important mediators of SOCE. Here, we review the role of several additional families of Ca(2+) channels expressed on the plasma membrane of T cells that likely contribute to Ca(2+) influx following TCR engagement, particularly highlighting an important role for voltage-dependent Ca(2+) channels (CaV) in T lymphocyte biology.
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Affiliation(s)
- Kyla D Omilusik
- Michael Smith Laboratories, University of British Columbia , Vancouver, BC , Canada ; Centre for Blood Research, University of British Columbia , Vancouver, BC , Canada ; The Brain Research Centre, University of British Columbia , Vancouver, BC , Canada ; Department of Microbiology and Immunology, University of British Columbia , Vancouver, BC , Canada ; Department of Medical Genetics, University of British Columbia , Vancouver, BC , Canada ; Department of Zoology, University of British Columbia , Vancouver, BC , Canada
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25
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Abstract
Cytoplasmic Ca(2+) is an universal intracellular messenger that activates cellular responses over a broad temporal range, from neurotransmitter release to cell growth and proliferation. Inherent to the use of the multifarious Ca(2+) signal is the question of specificity: how can some Ca(2+)-dependent responses be activated in a cell and not others? A rise in cytoplasmic Ca(2+) can evoke a response either by binding directly to the target (as occurs with certain Ca(2+)-activated K(+) and Cl(-) channels, for example) or through recruitment of intermediary proteins, such as calmodulin and troponin C. A substantial body of evidence has now established that Ca(2+)-binding proteins differ both in their affinities for Ca(2+) and in their on- and off-rates for Ca(2+) binding/unbinding. Furthermore, different Ca(2+)-binding proteins often occupy distinct locations within the cell. Therefore, the size, kinetics and spatial profile of a cytoplasmic Ca(2+) signal are all important in determining which Ca(2+)-dependent response will be activated, when and for how long.
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Affiliation(s)
- Pulak Kar
- Department of Physiology, Anatomy and Genetics; University of Oxford; Oxford, UK
| | - Anant Parekh
- Department of Physiology, Anatomy and Genetics; University of Oxford; Oxford, UK
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26
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Abstract
In many animal cells, store-operated Ca(2+) release-activated Ca(2+) (CRAC) channels function as an essential route for Ca(2+) entry. CRAC channels control many fundamental cellular functions including gene expression, motility, and cell proliferation, are involved in the etiology of several disease processes including a severe combined immunodeficiency syndrome, and have emerged as major targets for drug development. Although little was known of the molecular mechanisms of CRAC channel operation for several decades, the discovery of Orai1 as a prototypic CRAC channel protein and STIM1 as the endoplasmic reticulum (ER) Ca(2+) sensor has led to rapid progress in our understanding of the mechanisms and functions of CRAC channels. It is now known that activation of CRAC channels following ER Ca(2+) store depletion is governed by several events, which include the redistributions and accumulations of STIM1 and Orai1 into overlapping puncta at peripheral cellular sites, resulting in direct protein-protein interactions between the two proteins. In this chapter, I review the molecular features of the STIM and Orai proteins that regulate the gating and ion conduction mechanisms of CRAC channels.
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Affiliation(s)
- Murali Prakriya
- Department of Molecular Pharmacology and Biological Chemistry, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, USA.
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Schwarz EC, Qu B, Hoth M. Calcium, cancer and killing: the role of calcium in killing cancer cells by cytotoxic T lymphocytes and natural killer cells. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2012; 1833:1603-11. [PMID: 23220009 DOI: 10.1016/j.bbamcr.2012.11.016] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2012] [Revised: 11/16/2012] [Accepted: 11/18/2012] [Indexed: 01/13/2023]
Abstract
Killing cancer cells by cytotoxic T lymphocytes (CTL) and by natural killer (NK) cells is of vital importance. Cancer cell proliferation and apoptosis depend on the intracellular Ca(2+) concentration, and the expression of numerous ion channels with the ability to control intracellular Ca(2+) concentrations has been correlated with cancer. A rise of intracellular Ca(2+) concentrations is also required for efficient CTL and NK cell function and thus for killing their targets, in this case cancer cells. Here, we review the data on Ca(2+)-dependent killing of cancer cells by CTL and NK cells. In addition, we discuss emerging ideas and present a model how Ca(2+) may be used by CTL and NK cells to optimize their cancer cell killing efficiency. This article is part of a Special Issue entitled: 12th European Symposium on Calcium.
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Affiliation(s)
- Eva C Schwarz
- Department of Biophysics, Saarland University, Homburg, Germany
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Shi X, Bi Y, Yang W, Guo X, Jiang Y, Wan C, Li L, Bai Y, Guo J, Wang Y, Chen X, Wu B, Sun H, Liu W, Wang J, Xu C. Ca2+ regulates T-cell receptor activation by modulating the charge property of lipids. Nature 2012. [DOI: 10.1038/nature11699] [Citation(s) in RCA: 172] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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29
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Amyloid precursor protein-mediated modulation of capacitive calcium entry. CHINESE SCIENCE BULLETIN-CHINESE 2012. [DOI: 10.1007/s11434-012-5526-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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30
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Soboloff J, Rothberg BS, Madesh M, Gill DL. STIM proteins: dynamic calcium signal transducers. Nat Rev Mol Cell Biol 2012; 13:549-65. [PMID: 22914293 DOI: 10.1038/nrm3414] [Citation(s) in RCA: 508] [Impact Index Per Article: 42.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Stromal interaction molecule (STIM) proteins function in cells as dynamic coordinators of cellular calcium (Ca(2+)) signals. Spanning the endoplasmic reticulum (ER) membrane, they sense tiny changes in the levels of Ca(2+) stored within the ER lumen. As ER Ca(2+) is released to generate primary Ca(2+) signals, STIM proteins undergo an intricate activation reaction and rapidly translocate into junctions formed between the ER and the plasma membrane. There, STIM proteins tether and activate the highly Ca(2+)-selective Orai channels to mediate finely controlled Ca(2+) signals and to homeostatically balance cellular Ca(2+). Details are emerging on the remarkable organization within these STIM-induced junctional microdomains and the identification of new regulators and alternative target proteins for STIM.
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Affiliation(s)
- Jonathan Soboloff
- Department of Biochemistry, Temple University School of Medicine, 3400 North Broad Street, Philadelphia, Pennsylvania 19140, USA
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31
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Calcium microdomains at the immunological synapse: how ORAI channels, mitochondria and calcium pumps generate local calcium signals for efficient T-cell activation. EMBO J 2011; 30:3895-912. [PMID: 21847095 DOI: 10.1038/emboj.2011.289] [Citation(s) in RCA: 156] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2010] [Accepted: 07/19/2011] [Indexed: 12/24/2022] Open
Abstract
Cell polarization enables restriction of signalling into microdomains. Polarization of lymphocytes following formation of a mature immunological synapse (IS) is essential for calcium-dependent T-cell activation. Here, we analyse calcium microdomains at the IS with total internal reflection fluorescence microscopy. We find that the subplasmalemmal calcium signal following IS formation is sufficiently low to prevent calcium-dependent inactivation of ORAI channels. This is achieved by localizing mitochondria close to ORAI channels. Furthermore, we find that plasma membrane calcium ATPases (PMCAs) are re-distributed into areas beneath mitochondria, which prevented PMCA up-modulation and decreased calcium export locally. This nano-scale distribution-only induced following IS formation-maximizes the efficiency of calcium influx through ORAI channels while it decreases calcium clearance by PMCA, resulting in a more sustained NFAT activity and subsequent activation of T cells.
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32
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Wenning AS, Neblung K, Strauß B, Wolfs MJ, Sappok A, Hoth M, Schwarz EC. TRP expression pattern and the functional importance of TRPC3 in primary human T-cells. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2011; 1813:412-23. [DOI: 10.1016/j.bbamcr.2010.12.022] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2010] [Revised: 12/22/2010] [Accepted: 12/23/2010] [Indexed: 11/16/2022]
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Park CY, Shcheglovitov A, Dolmetsch R. The CRAC channel activator STIM1 binds and inhibits L-type voltage-gated calcium channels. Science 2010; 330:101-5. [PMID: 20929812 DOI: 10.1126/science.1191027] [Citation(s) in RCA: 263] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Voltage- and store-operated calcium (Ca(2+)) channels are the major routes of Ca(2+) entry in mammalian cells, but little is known about how cells coordinate the activity of these channels to generate coherent calcium signals. We found that STIM1 (stromal interaction molecule 1), the main activator of store-operated Ca(2+) channels, directly suppresses depolarization-induced opening of the voltage-gated Ca(2+) channel Ca(V)1.2. STIM1 binds to the C terminus of Ca(V)1.2 through its Ca(2+) release-activated Ca(2+) activation domain, acutely inhibits gating, and causes long-term internalization of the channel from the membrane. This establishes a previously unknown function for STIM1 and provides a molecular mechanism to explain the reciprocal regulation of these two channels in cells.
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Affiliation(s)
- Chan Young Park
- Department of Neurobiology, Stanford University School of Medicine, Stanford, CA 94305, USA
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34
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Krummel MF, Cahalan MD. The immunological synapse: a dynamic platform for local signaling. J Clin Immunol 2010; 30:364-72. [PMID: 20390326 PMCID: PMC2874029 DOI: 10.1007/s10875-010-9393-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2010] [Accepted: 03/16/2010] [Indexed: 01/06/2023]
Abstract
The immunological synapse (IS) as a concept has evolved from a static view of the junction between T cells and their antigen-presenting cell partners. The entire process of IS formation and extinction is now known to entail a dynamic reorganization of membrane domains and proteins within and adjacent to those domains. Discussion The entire process is also intricately tied to the motility machinery—both as that machinery directs “scanning” prior to T-cell receptor engagement and as it is appropriated during the ongoing developments at the IS. While the synapse often remains dynamic in order to encourage surveillance of new antigen-presenting surfaces, cytoskeletal forces also regulate the development of signals, likely including the assembly of ion channels. In both neuronal and immunological synapses, localized Ca2+ signals and accumulation or depletion of ions in microdomains accompany the concentration of signaling molecules in the synapse. Such spatiotemporal signaling in the synapse greatly accelerates kinetics and provides essential checkpoints to validate effective cell–cell communication.
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Affiliation(s)
- Matthew F Krummel
- Department of Pathology, University of California San Francisco, 513 Parnassus Avenue HSW-0511, San Francisco, CA 94143, USA.
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35
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Gao YD, Hanley PJ, Rinné S, Zuzarte M, Daut J. Calcium-activated K(+) channel (K(Ca)3.1) activity during Ca(2+) store depletion and store-operated Ca(2+) entry in human macrophages. Cell Calcium 2010; 48:19-27. [PMID: 20630587 DOI: 10.1016/j.ceca.2010.06.002] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2010] [Revised: 06/16/2010] [Accepted: 06/18/2010] [Indexed: 01/23/2023]
Abstract
STIM1 'senses' decreases in endoplasmic reticular (ER) luminal Ca(2+) and induces store-operated Ca(2+) (SOC) entry through plasma membrane Orai channels. The Ca(2+)/calmodulin-activated K(+) channel K(Ca)3.1 (previously known as SK4) has been implicated as an 'amplifier' of the Ca(2+)-release activated Ca(2+) (CRAC) current, especially in T lymphocytes. We have previously shown that human macrophages express K(Ca)3.1, and here we used the whole-cell patch-clamp technique to investigate the activity of these channels during Ca(2+) store depletion and store-operated Ca(2+) influx. Using RT-PCR, we found that macrophages express the elementary CRAC channel components Orai1 and STIM1, as well as Orai2, Orai3 and STIM2, but not the putatively STIM1-activated channels TRPC1, TRPC3-7 or TRPV6. In whole-cell configuration, a robust Ca(2+)-induced outwardly rectifying K(+) current inhibited by clotrimazole and augmented by DC-EBIO could be detected, consistent with K(Ca)3.1 channel current (also known as intermediate-conductance IK1). Introduction of extracellular Ca(2+) following Ca(2+) store depletion via P2Y(2) receptors induced a robust charybdotoxin (CTX)- and 2-APB-sensitive outward K(+) current and hyperpolarization. We also found that SOC entry induced by thapsigargin treatment induced CTX-sensitive K(+) current in HEK293 cells transiently expressing K(Ca)3.1. Our data suggest that SOC and K(Ca)3.1 channels are tightly coupled, such that a small Ca(2+) influx current induces a much large K(Ca)3.1 channel current and hyperpolarization, providing the necessary electrochemical driving force for prolonged Ca(2+) signaling and store repletion.
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Affiliation(s)
- Ya-dong Gao
- Institut für Physiologie und Pathophysiologie, Universität Marburg, Deutschhausstr. 2, 35037 Marburg, Germany.
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36
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Hogan PG, Lewis RS, Rao A. Molecular basis of calcium signaling in lymphocytes: STIM and ORAI. Annu Rev Immunol 2010; 28:491-533. [PMID: 20307213 DOI: 10.1146/annurev.immunol.021908.132550] [Citation(s) in RCA: 589] [Impact Index Per Article: 42.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Ca(2+) entry into cells of the peripheral immune system occurs through highly Ca(2+)-selective channels known as CRAC (calcium release-activated calcium) channels. CRAC channels are a very well-characterized example of store-operated Ca(2+) channels, so designated because they open when the endoplasmic reticulum (ER) Ca(2+) store becomes depleted. Physiologically, Ca(2+) is released from the ER lumen into the cytoplasm when activated receptors couple to phospholipase C and trigger production of the second messenger inositol 1,4,5-trisphosphate (IP(3)). IP(3) binds to IP(3) receptors in the ER membrane and activates Ca(2+) release. The proteins STIM and ORAI were discovered through limited and genome-wide RNAi screens, respectively, performed in Drosophila cells and focused on identifying modulators of store-operated Ca(2+) entry. STIM1 and STIM2 sense the depletion of ER Ca(2+) stores, whereas ORAI1 is a pore subunit of the CRAC channel. In this review, we discuss selected aspects of Ca(2+) signaling in cells of the immune system, focusing on the roles of STIM and ORAI proteins in store-operated Ca(2+) entry.
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Affiliation(s)
- Patrick G Hogan
- Department of Pathology, Harvard Medical School, Immune Disease Institute, Children's Hospital Boston, Massachusetts 02115, USA.
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37
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Schwindling C, Quintana A, Krause E, Hoth M. Mitochondria Positioning Controls Local Calcium Influx in T Cells. THE JOURNAL OF IMMUNOLOGY 2009; 184:184-90. [DOI: 10.4049/jimmunol.0902872] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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38
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Abstract
The Ca2+release-activated Ca2+ (CRAC) channel is a highly Ca2+-selective store-operated channel expressed in T cells, mast cells, and various other tissues. CRAC channels regulate critical cellular processes such as gene expression, motility, and the secretion of inflammatory mediators. The identification of Orai1, a key subunit of the CRAC channel pore, and STIM1, the endoplasmic reticulum (ER) Ca2+ sensor, have provided the tools to illuminate the mechanisms of regulation and the pore properties of CRAC channels. Recent evidence indicates that the activation of CRAC channels by store depletion involves a coordinated series of steps, which include the redistributions of STIM1 and Orai1, direct physical interactions between these proteins, and conformational changes in Orai1, culminating in channel activation. Additional studies have revealed that the high Ca2+ selectivity of CRAC channels arises from the presence of an intrapore Ca2+ binding site, the properties of which are finely honed to occlude the permeation of the much more prevalent Na+. Structure-function studies have led to the identification of the potential pore-binding sites for Ca2+, providing a firm framework for understanding the mechanisms of selectivity and gating of the CRAC channel. This review summarizes recent progress in understanding the mechanisms of CRAC channel activation, pore properties, and modulation.
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Affiliation(s)
- Murali Prakriya
- Department of Molecular Pharmacology and Biological Chemistry, Northwestern University School of Medicine, Chicago, IL 60611, USA.
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39
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Thiel M, Wolfs MJ, Bauer S, Wenning AS, Burckhart T, Schwarz EC, Scott AM, Renner C, Hoth M. Efficiency of T-cell costimulation by CD80 and CD86 cross-linking correlates with calcium entry. Immunology 2009; 129:28-40. [PMID: 19824921 DOI: 10.1111/j.1365-2567.2009.03155.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Costimulation is a fundamental principle of T-cell activation. In addition to T-cell receptor engagement, the interaction between CD80 and/or CD86 with CD28 and/or cytotoxic T-lymphocyte antigen 4 (CTLA-4) receptors is required to regulate T-cell activation and tolerance. While the importance of costimulation is clearly established, the exact molecular mechanism is unknown. We demonstrate that T-cell proliferation and the ability of CD8(+) T-effector cells to kill were enhanced slightly by CD80 but dramatically by CD86 costimulation. To further analyse the cellular process of costimulation, we developed a single-cell assay to analyse Ca(2+) signals following costimulation with bi-specific antibodies. We found that this stimulation method worked in every human T-cell that was analysed, making it one of the most efficient T-cell activation methods to date for primary human T cells. The enhanced proliferation and killing by costimulation was paralleled by an increase of Ca(2+) influx following CD86 costimulation and it was dependent on CD28/CTLA-4 expression. The enhanced Ca(2+) influx following CD86 costimulation was abrogated by an antibody that interfered with CD28 function. The differences in Ca(2+) influx between CD80 and CD86 costimulation were not dependent on the depletion of Ca(2+) stores but were eliminated by the application of 10 mum 2-aminoethyldiphenyl borate which has recently been shown to enhance stromal interaction molecule 2 (STIM2)-dependent Ca(2+) entry while reducing STIM1-dependent Ca(2+) entry. Our data indicate that differences in the efficiency of costimulation are linked to differences in Ca(2+) entry.
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Affiliation(s)
- Markus Thiel
- Klinik und Poliklinik für Onkologie, Universitäts-Spital Zürich, Zürich, Switzerland
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40
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Barr VA, Bernot KM, Shaffer MH, Burkhardt JK, Samelson LE. Formation of STIM and Orai complexes: puncta and distal caps. Immunol Rev 2009; 231:148-59. [PMID: 19754895 PMCID: PMC3110759 DOI: 10.1111/j.1600-065x.2009.00812.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
In the last few years, great progress has been made in understanding how stromal interacting molecule 1 (STIM1), a protein containing a calcium sensor that is located in the endoplasmic reticulum, and Orai1, a protein that forms a calcium channel in the plasma membrane, interact and give rise to store-operated calcium entry. Pharmacological depletion of calcium stores leads to the formation of clusters containing STIM and Orai that appear to be sites for calcium influx. Similar puncta are also produced in response to physiological stimuli in immune cells. In T cells engaged with antigen-presenting cells, clusters containing STIM and Orai accumulate at the immunological synapse. We recently discovered that in activated T cells, STIM1 and Orai1 also accumulate in cap-like structures opposite the immune synapse at the distal pole of the cell. Both caps and puncta are long-lived stable structures containing STIM1 and Orai1 in close proximity. The function of puncta as sites of calcium influx is clear. We speculate that the caps may provide a secondary site of calcium entry. Alternatively, they may serve as a source of preformed channel complexes that move to new immune synapses as T cells repeatedly engage antigen-presenting cells.
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Affiliation(s)
- Valarie A Barr
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA.
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41
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Kummerow C, Junker C, Kruse K, Rieger H, Quintana A, Hoth M. The immunological synapse controls local and global calcium signals in T lymphocytes. Immunol Rev 2009; 231:132-47. [DOI: 10.1111/j.1600-065x.2009.00811.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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42
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Birnbaumer L. The TRPC class of ion channels: a critical review of their roles in slow, sustained increases in intracellular Ca(2+) concentrations. Annu Rev Pharmacol Toxicol 2009; 49:395-426. [PMID: 19281310 DOI: 10.1146/annurev.pharmtox.48.113006.094928] [Citation(s) in RCA: 162] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The realization that there exists a multimembered family of cation channels with structural similarity to Drosophila's Trp channel emerged during the second half of the 1990s. In mammals, depending on the species, the TRP family counts 29 or 30 members which has been subdivided into 6 subfamilies on the basis of sequence similarity. TRP channels are nonselective monovalent cation channels, most of which also allow passage of Ca(2+). Many members of each of these families, but not all, are involved in sensory signal transduction. The C-type (for canonical or classical) subfamily, differs from the other TRP subfamilies in that it fulfills two different types of function: membrane depolarization, resembling sensory transduction TRPs, and mediation of sustained increases in intracellular Ca(2+). The mechanism(s) by which the C-class of TRP channels-the TRPCs-are activated is poorly understood and their role in mediating intracellular Ca(2+) increases is being questioned. Both of these questions-mechanism of activation and participation in Ca(2+) entry-are the topics of this review.
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Affiliation(s)
- Lutz Birnbaumer
- National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina 27709, USA.
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43
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Cioffi DL, Lowe K, Alvarez DF, Barry C, Stevens T. TRPing on the lung endothelium: calcium channels that regulate barrier function. Antioxid Redox Signal 2009; 11:765-76. [PMID: 18783312 PMCID: PMC2850299 DOI: 10.1089/ars.2008.2221] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Rises in cytosolic calcium are sufficient to initiate the retraction of endothelial cell borders and to increase macromolecular permeability. Although endothelial cell biologists have recognized the importance of shifts in cytosolic calcium for several decades, only recently have we gained a rudimentary understanding of the membrane calcium channels that change cell shape. Members of the transient receptor potential family (TRP) are chief among the molecular candidates for permeability-coupled calcium channels. Activation of calcium entry through store-operated calcium entry channels, most notably TRPC1 and TRPC4, increases lung endothelial cell permeability, as does activation of calcium entry through the TRPV4 channel. However, TRPC1 and TRPC4 channels appear to influence the lung extraalveolar endothelial barrier most prominently, whereas TRPV4 channels appear to influence the lung capillary endothelial barrier most prominently. Thus, phenotypic heterogeneity in ion channel expression and function exists within the lung endothelium, along the arterial-capillary-venous axis, and is coupled to discrete control of endothelial barrier function.
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Affiliation(s)
- Donna L Cioffi
- Center for Lung Biology, University of South Alabama, Mobile, Alabama 36688, USA
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44
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Yang S, Zhang JJ, Huang XY. Orai1 and STIM1 are critical for breast tumor cell migration and metastasis. Cancer Cell 2009; 15:124-34. [PMID: 19185847 DOI: 10.1016/j.ccr.2008.12.019] [Citation(s) in RCA: 527] [Impact Index Per Article: 35.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2008] [Revised: 08/28/2008] [Accepted: 12/29/2008] [Indexed: 11/26/2022]
Abstract
Tumor metastasis is the primary cause of death of cancer patients. Understanding the molecular mechanisms underlying tumor metastasis will provide potential drug targets. We report here that Orai1 and STIM1, both of which are involved in store-operated calcium entry, are essential for breast tumor cell migration in vitro and tumor metastasis in mice. Reduction of Orai1 or STIM1 by RNA interference in highly metastatic human breast cancer cells or treatment with a pharmacological inhibitor of store-operated calcium channels decreased tumor metastasis in animal models. Our data demonstrate a role for Orai1 and STIM1 in tumor metastasis and suggest store-operated calcium entry channels as potential cancer therapeutic targets.
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Affiliation(s)
- Shengyu Yang
- Department of Physiology, Weill Medical College of Cornell University, New York, NY 10065, USA
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45
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Ozawa T, Kinoshita K, Kadowaki S, Tajiri K, Kondo S, Honda R, Ikemoto M, Piao L, Morisato A, Fukurotani K, Kishi H, Muraguchi A. MAC-CCD system: a novel lymphocyte microwell-array chip system equipped with CCD scanner to generate human monoclonal antibodies against influenza virus. LAB ON A CHIP 2009; 9:158-63. [PMID: 19209349 DOI: 10.1039/b810438g] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We previously developed a lymphocyte microwell-array system, which effectively detects antigen-specific B-cells by monitoring intracellular Ca(2+) mobilization at the single-cell level with a fluorescent Ca(2+) indicator, fluo-4. However, it is difficult for the system to perform time-lapse monitoring. Here, we developed a novel method, a lymphocyte microwell-array chip system equipped with a charge-coupled device (CCD) time-lapse scanner (MAC-CCD system), for monitoring intracellular Ca(2+) mobilization. The MAC-CCD system is able to monitor intracellular Ca(2+) mobilization of more than 15,000-20,000 individual live B-cells every 10 s. In addition, we adopted a correlation method in a MAC-CCD system, which enabled us to detect B-cells with a frequency of as few as 0.046%. Furthermore, we succeeded in obtaining six influenza nucleoprotein-specific human monoclonal antibodies from the peripheral blood of influenza-vaccinated volunteers. These results demonstrate that the MAC-CCD system with a correlation method could detect very rare antigen-specific B-cells.
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Affiliation(s)
- T Ozawa
- Department of Immunology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama, 930-0194, Japan
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46
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Krishnan S, Juang YT, Chowdhury B, Magilavy A, Fisher CU, Nguyen H, Nambiar MP, Kyttaris V, Weinstein A, Bahjat R, Pine P, Rus V, Tsokos GC. Differential expression and molecular associations of Syk in systemic lupus erythematosus T cells. THE JOURNAL OF IMMUNOLOGY 2008; 181:8145-52. [PMID: 19018007 DOI: 10.4049/jimmunol.181.11.8145] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Diminished expression of TCR zeta and reciprocal up-regulation and association of FcRgamma with the TCR/CD3 complex is a hallmark of systemic lupus erythematosus (SLE) T cells. In this study we explored whether differential molecular associations of the spleen tyrosine kinase Syk that preferentially binds to FcRgamma contribute to pathological amplification of signals downstream of this "rewired TCR" in SLE. We detected higher amounts of Syk expression and activity in SLE compared with normal T cells. Selective inhibition of the activity of Syk reduced the strength of TCR-induced calcium responses and slowed the rapid kinetics of actin polymerization exclusively in SLE T cells. Syk and ZAP-70 also associated differently with key molecules involved in cytoskeletal and calcium signaling in SLE T cells. Thus, while Vav-1 and LAT preferentially bound to Syk, phospholipase C-gamma1 bound to both Syk and ZAP-70. Our results show that differential associations of Syk family kinases contribute to the enhanced TCR-induced signaling responses in SLE T cells. Thus, we propose molecular targeting of Syk as a measure to control abnormal T cell responses in SLE.
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Affiliation(s)
- Sandeep Krishnan
- Department of Cellular Injury, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA
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47
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Shideman CR, Reinardy JL, Thayer SA. gamma-Secretase activity modulates store-operated Ca2+ entry into rat sensory neurons. Neurosci Lett 2008; 451:124-8. [PMID: 19114088 DOI: 10.1016/j.neulet.2008.12.031] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2008] [Revised: 12/09/2008] [Accepted: 12/17/2008] [Indexed: 01/24/2023]
Abstract
Presenilin-1 is required for gamma-secretase activity, which participates in Notch receptor processing, the pathogenesis of Alzheimer's disease and the modulation of Ca(2+) signaling. We tested the hypothesis that gamma-secretase proteolytic activity modulates store-operated Ca(2+) entry (SOCE) in rat dorsal root ganglion (DRG) neurons. Depletion of intracellular Ca(2+) stores by blocking the endoplasmic reticulum (ER) Ca(2+) pump with cyclopiazonic acid (CPA) evoked a transient increase in [Ca(2+)](i) but no sustained Ca(2+) influx. However, in cells expressing a dominant negative presenilin-1 mutant (PS1-D257A), gamma-secretase activity was inhibited and treatment with CPA evoked sustained Ca(2+) influx. Similarly, pharmacologic inhibition of gamma-secretase with DAPT for 48h enhanced SOCE. SKF96365, an inhibitor of store-operated channels, blocked SOCE in cells expressing PS1-D257A. Thus, gamma-secretase proteolytic activity regulates a SOCE pathway in sensory neurons.
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Affiliation(s)
- Charles R Shideman
- Department of Pharmacology, University of Minnesota Medical School, 6-120 Jackson Hall, 321 Church Street SE, Minneapolis, MN 55455-0217, United States
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Yonetoku Y, Kubota H, Miyazaki Y, Okamoto Y, Funatsu M, Yoshimura-Ishikawa N, Ishikawa J, Yoshino T, Takeuchi M, Ohta M. Novel potent and selective Ca2+ release-activated Ca2+ (CRAC) channel inhibitors. Part 3: synthesis and CRAC channel inhibitory activity of 4'-[(trifluoromethyl)pyrazol-1-yl]carboxanilides. Bioorg Med Chem 2008; 16:9457-66. [PMID: 18835179 DOI: 10.1016/j.bmc.2008.09.047] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2008] [Revised: 09/16/2008] [Accepted: 09/17/2008] [Indexed: 11/28/2022]
Abstract
From a series of 4'-[(trifluoromethyl)pyrazol-1-yl]carboxanilides derived from 4-methyl-4'-[3,5-bis(trifluoromethyl)-1H-pyrazol-1-yl]-1,2,3-thiadiazole-5-carboxanilide, one inhibited thapsigargin-induced Ca2+ influx in Jurkat T cells (IC(50)=77 nM) and exhibited high selectivity for the CRAC channel over the VOC channel (index: >130). Another acted as an inhibitor for both T lymphocyte activation-induced diseases and ovalbumin-induced airway eosinophilia in rats (ED(50)=1.3 mg/kg) p.o.
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Affiliation(s)
- Yasuhiro Yonetoku
- Drug Discovery Research, Astellas Pharma Inc., 21 Miyukigaoka, Tsukuba, Ibaraki 305-8585, Japan.
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Quintana A, Kummerow C, Junker C, Becherer U, Hoth M. Morphological changes of T cells following formation of the immunological synapse modulate intracellular calcium signals. Cell Calcium 2008; 45:109-22. [PMID: 18789821 DOI: 10.1016/j.ceca.2008.07.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2008] [Revised: 07/08/2008] [Accepted: 07/09/2008] [Indexed: 10/21/2022]
Abstract
Sustained Ca(2+) influx through plasma membrane Ca(2+) released-activated Ca(2+) (CRAC) channels is essential for T cell activation. Since inflowing Ca(2+) inactivates CRAC channels, T cell activation is only possible if Ca(2+)-dependent inactivation is prevented. We have previously reported that sustained Ca(2+) influx through CRAC channels requires both mitochondrial Ca(2+) uptake and mitochondrial translocation towards the plasma membrane in order to prevent Ca(2+)-dependent channel inactivation. Here, we show that morphological changes following formation of the immunological synapse (IS) modulate Ca(2+) influx through CRAC channels. Cell shape changes were dependent on the actin cytoskeleton, and they sustained Ca(2+) entry by bringing mitochondria and the plasma membrane in closer proximity. The increased percentage of mitochondria beneath the plasma membrane following shape changes occurred in all 3 dimensions and correlated with an increase in the amplitude of Ca(2+) signals. The shape change-dependent mitochondrial localization close to the plasma membrane prevented CRAC channel inactivation even in T cells in which dynein motor protein-dependent mitochondria movements towards the plasma membrane were completely abolished, highlighting the importance of the shape change-dependent control of Ca(2+) influx. Our results suggest that morphological changes do not only facilitate an efficient contact with antigen presenting cells but also strongly modulate Ca(2+) dependent T cell activation.
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Affiliation(s)
- Ariel Quintana
- Department of Biophysics, University of Saarland, Homburg, Germany.
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Ahmed A, Mukherjee S, Nandi D. Intracellular concentrations of Ca(2+) modulate the strength of signal and alter the outcomes of cytotoxic T-lymphocyte antigen-4 (CD152)-CD80/CD86 interactions in CD4(+) T lymphocytes. Immunology 2008; 126:363-77. [PMID: 18710402 DOI: 10.1111/j.1365-2567.2008.02902.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The costimulatory receptors CD28 and cytotoxic T-lymphocyte antigen (CTLA)-4 and their ligands, CD80 and CD86, are expressed on T lymphocytes; however, their functional roles during T cell-T cell interactions are not well known. The consequences of blocking CTLA-4-CD80/CD86 interactions on purified mouse CD4(+) T cells were studied in the context of the strength of signal (SOS). CD4(+) T cells were activated with phorbol 12-myristate 13-acetate (PMA) and different concentrations of a Ca(2+) ionophore, Ionomycin (I), or a sarcoplasmic Ca(2+) ATPase inhibitor, Thapsigargin (TG). Increasing concentrations of I or TG increased the amount of interleukin (IL)-2, reflecting the conversion of a low to a high SOS. During activation with PMA and low amounts of I, intracellular concentrations of calcium ([Ca(2+)](i)) were greatly reduced upon CTLA-4-CD80/CD86 blockade. Further experiments demonstrated that CTLA-4-CD80/CD86 interactions reduced cell cycling upon activation with PMA and high amounts of I or TG (high SOS) but the opposite occurred with PMA and low amounts of I or TG (low SOS). These results were confirmed by surface T-cell receptor (TCR)-CD3 signalling using a low SOS, for example soluble anti-CD3, or a high SOS, for example plate-bound anti-CD3. Also, CTLA-4-CD80/CD86 interactions enhanced the generation of reactive oxygen species (ROS). Studies with catalase revealed that H(2)O(2) was required for IL-2 production and cell cycle progression during activation with a low SOS. However, the high amounts of ROS produced during activation with a high SOS reduced cell cycle progression. Taken together, these results indicate that [Ca(2+)](i) and ROS play important roles in the modulation of T-cell responses by CTLA-4-CD80/CD86 interactions.
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Affiliation(s)
- Asma Ahmed
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
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