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Sallinger M, Grabmayr H, Humer C, Bonhenry D, Romanin C, Schindl R, Derler I. Activation mechanisms and structural dynamics of STIM proteins. J Physiol 2024; 602:1475-1507. [PMID: 36651592 DOI: 10.1113/jp283828] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Accepted: 01/11/2023] [Indexed: 01/19/2023] Open
Abstract
The family of stromal interaction molecules (STIM) includes two widely expressed single-pass endoplasmic reticulum (ER) transmembrane proteins and additional splice variants that act as precise ER-luminal Ca2+ sensors. STIM proteins mainly function as one of the two essential components of the so-called Ca2+ release-activated Ca2+ (CRAC) channel. The second CRAC channel component is constituted by pore-forming Orai proteins in the plasma membrane. STIM and Orai physically interact with each other to enable CRAC channel opening, which is a critical prerequisite for various downstream signalling pathways such as gene transcription or proliferation. Their activation commonly requires the emptying of the intracellular ER Ca2+ store. Using their Ca2+ sensing capabilities, STIM proteins confer this Ca2+ content-dependent signal to Orai, thereby linking Ca2+ store depletion to CRAC channel opening. Here we review the conformational dynamics occurring along the entire STIM protein upon store depletion, involving the transition from the quiescent, compactly folded structure into an active, extended state, modulation by a variety of accessory components in the cell as well as the impairment of individual steps of the STIM activation cascade associated with disease.
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Affiliation(s)
- Matthias Sallinger
- Institute of Biophysics, JKU Life Science Center, Johannes Kepler University Linz, Linz, Austria
| | - Herwig Grabmayr
- Institute of Biophysics, JKU Life Science Center, Johannes Kepler University Linz, Linz, Austria
| | - Christina Humer
- Institute of Biophysics, JKU Life Science Center, Johannes Kepler University Linz, Linz, Austria
| | - Daniel Bonhenry
- Center for Nanobiology and Structural Biology, Institute of Microbiology, Academy of Sciences of the Czech Republic, Nove Hrady, Czech Republic
| | - Christoph Romanin
- Institute of Biophysics, JKU Life Science Center, Johannes Kepler University Linz, Linz, Austria
| | - Rainer Schindl
- Gottfried Schatz Research Centre, Medical University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
| | - Isabella Derler
- Institute of Biophysics, JKU Life Science Center, Johannes Kepler University Linz, Linz, Austria
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2
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Benson JC, Romito O, Abdelnaby AE, Xin P, Pathak T, Weir SE, Kirk V, Castaneda F, Yoast RE, Emrich SM, Tang PW, Yule DI, Hempel N, Potier-Cartereau M, Sneyd J, Trebak M. A multiple-oscillator mechanism underlies antigen-induced Ca 2+ oscillations in Jurkat T-cells. J Biol Chem 2023; 299:105310. [PMID: 37778728 PMCID: PMC10641176 DOI: 10.1016/j.jbc.2023.105310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2023] [Revised: 09/11/2023] [Accepted: 09/20/2023] [Indexed: 10/03/2023] Open
Abstract
T-cell receptor stimulation triggers cytosolic Ca2+ signaling by inositol-1,4,5-trisphosphate (IP3)-mediated Ca2+ release from the endoplasmic reticulum (ER) and Ca2+ entry through Ca2+ release-activated Ca2+ (CRAC) channels gated by ER-located stromal-interacting molecules (STIM1/2). Physiologically, cytosolic Ca2+ signaling manifests as regenerative Ca2+ oscillations, which are critical for nuclear factor of activated T-cells-mediated transcription. In most cells, Ca2+ oscillations are thought to originate from IP3 receptor-mediated Ca2+ release, with CRAC channels indirectly sustaining them through ER refilling. Here, experimental and computational evidence support a multiple-oscillator mechanism in Jurkat T-cells whereby both IP3 receptor and CRAC channel activities oscillate and directly fuel antigen-evoked Ca2+ oscillations, with the CRAC channel being the major contributor. KO of either STIM1 or STIM2 significantly reduces CRAC channel activity. As such, STIM1 and STIM2 synergize for optimal Ca2+ oscillations and activation of nuclear factor of activated T-cells 1 and are essential for ER refilling. The loss of both STIM proteins abrogates CRAC channel activity, drastically reduces ER Ca2+ content, severely hampers cell proliferation and enhances cell death. These results clarify the mechanism and the contribution of STIM proteins to Ca2+ oscillations in T-cells.
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Affiliation(s)
- J Cory Benson
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA; Vascular Medicine Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA; Graduate Program in Cellular and Molecular Physiology, The Pennsylvania State University College of Medicine, Hershey, Pennsylvania, USA
| | - Olivier Romito
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA; Vascular Medicine Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA; Inserm UMR 1069, Nutrition Croissance Cancer, Faculté de Médecine, Université de Tours, Tours, France
| | - Ahmed Emam Abdelnaby
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA; Vascular Medicine Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Ping Xin
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA; Vascular Medicine Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Trayambak Pathak
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA; Vascular Medicine Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Sierra E Weir
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA; Vascular Medicine Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Vivien Kirk
- Department of Mathematics, University of Auckland, Auckland, New Zealand
| | | | - Ryan E Yoast
- Graduate Program in Cellular and Molecular Physiology, The Pennsylvania State University College of Medicine, Hershey, Pennsylvania, USA
| | - Scott M Emrich
- Graduate Program in Cellular and Molecular Physiology, The Pennsylvania State University College of Medicine, Hershey, Pennsylvania, USA
| | - Priscilla W Tang
- Division of Hematology/Oncology, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA; UPMC Hillman Cancer Center, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - David I Yule
- Department of Pharmacology and Physiology, University of Rochester, Rochester, New York, USA
| | - Nadine Hempel
- Division of Hematology/Oncology, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA; UPMC Hillman Cancer Center, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Marie Potier-Cartereau
- Inserm UMR 1069, Nutrition Croissance Cancer, Faculté de Médecine, Université de Tours, Tours, France
| | - James Sneyd
- Department of Mathematics, University of Auckland, Auckland, New Zealand
| | - Mohamed Trebak
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA; Vascular Medicine Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA; UPMC Hillman Cancer Center, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.
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3
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Becchetti A. Interplay of Ca 2+ and K + signals in cell physiology and cancer. Ion Channels in Cancer 2023; 92:15-46. [PMID: 38007266 DOI: 10.1016/bs.ctm.2023.09.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2023]
Abstract
The cytoplasmic Ca2+ concentration and the activity of K+ channels on the plasma membrane regulate cellular processes ranging from mitosis to oriented migration. The interplay between Ca2+ and K+ signals is intricate, and different cell types rely on peculiar cellular mechanisms. Derangement of these mechanisms accompanies the neoplastic progression. The calcium signals modulated by voltage-gated (KV) and calcium-dependent (KCa) K+ channel activity regulate progression of the cell division cycle, the release of growth factors, apoptosis, cell motility and migration. Moreover, KV channels regulate the cell response to the local microenvironment by assembling with cell adhesion and growth factor receptors. This chapter summarizes the pathophysiological roles of Ca2+ and K+ fluxes in normal and cancer cells, by concentrating on several biological systems in which these functions have been studied in depth, such as early embryos, mammalian cell lines, T lymphocytes, gliomas and colorectal cancer cells. A full understanding of the underlying mechanisms will offer a comprehensive view of the ion channel implication in cancer biology and suggest potential pharmacological targets for novel therapeutic approaches in oncology.
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Affiliation(s)
- Andrea Becchetti
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milano, Italy.
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4
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Ali S, Ma G, Zhou Y. Shedding light on ORAI1 channel with genetic code expansion. Cell Calcium 2023; 113:102755. [PMID: 37196487 PMCID: PMC10484295 DOI: 10.1016/j.ceca.2023.102755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Accepted: 05/09/2023] [Indexed: 05/19/2023]
Abstract
Genetic code expansion technology has been widely applied to control protein activity and biological systems by taking advantage of an amber stop codon suppressor tRNA and orthogonal aminoacyl-tRNA synthetase pair. With this chemical biology approach, Maltan et al. incorporated photocrosslinking unnatural amino acids (UAAs) into the transmembrane domains of ORAI1 to enable UV light-inducible calcium influx across the plasma membrane, mechanistic interrogation of the calcium release-activated calcium (CRAC) channel at the single amino acid level, and remote control of downstream calcium-modulated signaling in mammalian cells.
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Affiliation(s)
- Sher Ali
- Center for Translational Cancer Research, Institute of Biosciences and Technology, Texas A&M University, Houston, TX, 77030, United States of America
| | - Guolin Ma
- Center for Translational Cancer Research, Institute of Biosciences and Technology, Texas A&M University, Houston, TX, 77030, United States of America; Department of Translational Medical Sciences, School of Medicine, Texas A&M University, Houston, TX, 77030, United States of America.
| | - Yubin Zhou
- Center for Translational Cancer Research, Institute of Biosciences and Technology, Texas A&M University, Houston, TX, 77030, United States of America; Department of Translational Medical Sciences, School of Medicine, Texas A&M University, Houston, TX, 77030, United States of America.
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Benson JC, Trebak M. Too much of a good thing: The case of SOCE in cellular apoptosis. Cell Calcium 2023; 111:102716. [PMID: 36931194 PMCID: PMC10481469 DOI: 10.1016/j.ceca.2023.102716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 03/06/2023] [Accepted: 03/09/2023] [Indexed: 03/13/2023]
Abstract
Intracellular calcium (Ca2+) is an essential second messenger in eukaryotic cells regulating numerous cellular functions such as contraction, secretion, immunity, growth, and metabolism. Ca2+ signaling is also a key signal transducer in the intrinsic apoptosis pathway. The store-operated Ca2+ entry pathway (SOCE) is ubiquitously expressed in eukaryotic cells, and is the primary Ca2+ influx pathway in non-excitable cells. SOCE is mediated by the endoplasmic reticulum Ca2+ sensing STIM proteins, and the plasma membrane Ca2+-selective Orai channels. A growing number of studies have implicated SOCE in regulating cell death primarily via the intrinsic apoptotic pathway in a variety of tissues and in response to physiological stressors such as traumatic brain injury, ischemia reperfusion injury, sepsis, and alcohol toxicity. Notably, the literature points to excessive cytosolic Ca2+ influx through SOCE in vulnerable cells as a key factor tipping the balance towards cellular apoptosis. While the literature primarily addresses the functions of STIM1 and Orai1, STIM2, Orai2 and Orai3 are also emerging as potential regulators of cell death. Here, we review the functions of STIM and Orai proteins in regulating cell death and the implications of this regulation to human pathologies.
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Affiliation(s)
- J Cory Benson
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, 200 Lothrop Street, Pittsburgh, PA 1526, USA; Vascular Medicine Institute, University of Pittsburgh School of Medicine, 200 Lothrop Street, Pittsburgh, PA 1526, USA; Department of Cellular and Molecular Physiology, Graduate Program, The Pennsylvania State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
| | - Mohamed Trebak
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, 200 Lothrop Street, Pittsburgh, PA 1526, USA; Vascular Medicine Institute, University of Pittsburgh School of Medicine, 200 Lothrop Street, Pittsburgh, PA 1526, USA; UPMC Hillman Cancer Center, University of Pittsburgh School of Medicine, 200 Lothrop Street, Pittsburgh, PA 1526, USA.
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6
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Sarkar P, Bhat A, Chattopadhyay A. Lysine 101 in the CRAC Motif in Transmembrane Helix 2 Confers Cholesterol-Induced Thermal Stability to the Serotonin 1A Receptor. J Membr Biol 2022; 255:739-746. [PMID: 35986776 DOI: 10.1007/s00232-022-00262-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 08/05/2022] [Indexed: 12/24/2022]
Abstract
G protein-coupled receptors (GPCRs) constitute the largest class of membrane proteins that transduce signals across the plasma membrane and orchestrate a multitude of physiological processes within cells. The serotonin1A receptor is a crucial neurotransmitter receptor in the GPCR family involved in a multitude of neurological, behavioral and cognitive functions. We have previously shown, using a combination of experimental and simulation approaches, that membrane cholesterol acts as a key regulator of organization, dynamics, signaling and endocytosis of the serotonin1A receptor. In addition, we showed that membrane cholesterol stabilizes the serotonin1A receptor against thermal deactivation. In the present work, we explored the molecular basis of cholesterol-induced thermal stability of the serotonin1A receptor. For this, we explored the possible role of the K101 residue in a cholesterol recognition/interaction amino acid consensus (CRAC) motif in transmembrane helix 2 in conferring the thermal stability of the serotonin1A receptor. Our results show that a mutation in the K101 residue leads to loss in thermal stability of the serotonin1A receptor imparted by cholesterol, independent of membrane cholesterol content. We envision that our results could have potential implications in structural biological advancements of GPCRs and design of thermally stabilized receptors for drug development.
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Affiliation(s)
- Parijat Sarkar
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, 500 007, India
| | - Akrati Bhat
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, 500 007, India
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Jardin I, Berna-Erro A, Nieto-Felipe J, Macias A, Sanchez-Collado J, Lopez JJ, Salido GM, Rosado JA. Similarities and Differences between the Orai1 Variants: Orai1α and Orai1β. Int J Mol Sci 2022; 23:ijms232314568. [PMID: 36498894 PMCID: PMC9735889 DOI: 10.3390/ijms232314568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 11/16/2022] [Accepted: 11/21/2022] [Indexed: 11/24/2022] Open
Abstract
Orai1, the first identified member of the Orai protein family, is ubiquitously expressed in the animal kingdom. Orai1 was initially characterized as the channel responsible for the store-operated calcium entry (SOCE), a major mechanism that allows cytosolic calcium concentration increments upon receptor-mediated IP3 generation, which results in intracellular Ca2+ store depletion. Furthermore, current evidence supports that abnormal Orai1 expression or function underlies several disorders. Orai1 is, together with STIM1, the key element of SOCE, conducting the Ca2+ release-activated Ca2+ (CRAC) current and, in association with TRPC1, the store-operated Ca2+ (SOC) current. Additionally, Orai1 is involved in non-capacitative pathways, as the arachidonate-regulated or LTC4-regulated Ca2+ channel (ARC/LRC), store-independent Ca2+ influx activated by the secretory pathway Ca2+-ATPase (SPCA2) and the small conductance Ca2+-activated K+ channel 3 (SK3). Furthermore, Orai1 possesses two variants, Orai1α and Orai1β, the latter lacking 63 amino acids in the N-terminus as compared to the full-length Orai1α form, which confers distinct features to each variant. Here, we review the current knowledge about the differences between Orai1α and Orai1β, the implications of the Ca2+ signals triggered by each variant, and their downstream modulatory effect within the cell.
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8
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Vázquez-Prieto MLÁ, Lascurais-Santamaría N, Fernández-Eufrasio NB, Montiel-Condado D, Garibay-Escobar A, Patiño-López G, Penner R, Sumoza-Toledo A. Sex-dependent effect of aging on calcium signaling and expression of TRPM2 and CRAC channels in human neutrophils. Hum Immunol 2022:S0198-8859(22)00117-3. [PMID: 35660323 DOI: 10.1016/j.humimm.2022.05.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 04/26/2022] [Accepted: 05/15/2022] [Indexed: 11/22/2022]
Abstract
The vulnerability of older adults to bacterial infections has been associated with age-related changes in neutrophils. We analyzed the consequences of aging on calcium (Ca2+) mobilization and TRPM2 and CRAC channels expression in human neutrophils. The percentages of granulocytes, mature neutrophils, and neutrophil precursors were equivalent between young and older adults. However, neutrophil chemotaxis towards IL-8, C5a, or fMLP was lower in older adults of both sexes. Interestingly, a stronger Ca2+ transient followed by an identical Ca2+ influx to IL-8 was observed in older adult females. In addition, the Ca2+ response to LPS was delayed and prolonged in neutrophils of older adult males. There was no significant difference in Ca2+ response to fMLP, C5a, or store-operated Ca2+ entry in the older adults. There were also no differences in the expression of CXCR2, CD88, FPLR1, and TLR4. Interestingly, TRPM2- and ORAI1-mRNA expression was lower in neutrophils of older adults, mainly in females. Both channels were detected intracellularly in the neutrophils. TRPM2 was in late endosomes in young adults and in lysosomes in older adult neutrophils. In summary, defective neutrophil chemotaxis in aging seemed not to stem from alterations in Ca2+ signals; nevertheless, the low TRPM2 and ORAI1 expression may affect other functions.
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9
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Zhang N, Pan H, Liang X, Xie J, Han W. The roles of transmembrane family proteins in the regulation of store-operated Ca 2+ entry. Cell Mol Life Sci 2022; 79:118. [PMID: 35119538 DOI: 10.1007/s00018-021-04034-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 11/09/2021] [Accepted: 11/10/2021] [Indexed: 12/15/2022]
Abstract
Store-operated Ca2+ entry (SOCE) is a major pathway for calcium signaling, which regulates almost every biological process, involving cell proliferation, differentiation, movement and death. Stromal interaction molecule (STIM) and ORAI calcium release-activated calcium modulator (ORAI) are the two major proteins involved in SOCE. With the deepening of studies, more and more proteins are found to be able to regulate SOCE, among which the transmembrane (TMEM) family proteins are worth paying more attention. In addition, the ORAI proteins belong to the TMEM family themselves. As the name suggests, TMEM family is a type of proteins that spans biological membranes including plasma membrane and membrane of organelles. TMEM proteins are in a large family with more than 300 proteins that have been already identified, while the functional knowledge about the proteins is preliminary. In this review, we mainly summarized the TMEM proteins that are involved in SOCE, to better describe a picture of the interaction between STIM and ORAI proteins during SOCE and its downstream signaling pathways, as well as to provide an idea for the study of the TMEM family proteins.
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Affiliation(s)
- Ningxia Zhang
- Department of Medical Oncology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Hongming Pan
- Department of Medical Oncology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Xiaojing Liang
- Department of Medical Oncology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Jiansheng Xie
- Department of Medical Oncology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China. .,Laboratory of Cancer Biology, Institute of Clinical Science, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China.
| | - Weidong Han
- Department of Medical Oncology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China.
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10
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Sutter ML, Console L, Fahner AF, Samodelov SL, Gai Z, Ciarimboli G, Indiveri C, Kullak-Ublick GA, Visentin M. The role of cholesterol recognition (CARC/ CRAC) mirror codes in the allosterism of the human organic cation transporter 2 (OCT2, SLC22A2). Biochem Pharmacol 2021; 194:114840. [PMID: 34774844 DOI: 10.1016/j.bcp.2021.114840] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 11/08/2021] [Accepted: 11/09/2021] [Indexed: 11/21/2022]
Abstract
The human organic cation transporter 2 (OCT2) is a multispecific transporter with cholesterol-dependent allosteric features. The present work elucidates the role of evolutionarily conserved cholesterol recognition/interaction amino acid consensus sequences (CRAC and CARC) in the allosteric binding to 1-methyl-4-phenylpyridinium (MPP+) in human embryonic kidney 293 cells stably or transiently expressing OCT2. Molecular blind simulations docked two mirroring cholesterol molecules in the 5th putative transmembrane domain, where a CARC and a CRAC sequence lie. The impact of the conserved amino acids that may constitute the CARC/CRAC mirror code was studied by alanine-scanning mutagenesis. At a saturating extracellular concentration of substrate, at which the impact of cholesterol depletion is maximal, five mutants transported MPP+ at a significantly lower rate than the wild-type OCT2 (WT), resembling the behavior of the WT upon cholesterol depletion. MPP+ influx rate as a function of the extracellular concentration of substrate was measured for the mutants R234A, R235A, L252A and R263A. R234A kinetic behavior was similar to that of the WT, whereas R235A, L252A and R263A activity shifted from allosteric to one-binding site kinetics, very much like the WT upon cholesterol depletion. The impact of cholesterol on protein thermal stability was assessed for WT, R234A and R263A. While the thermal stability of WT and R234A was improved by the supplementation with cholesterol, R263A was not sensitive to the presence of cholesterol. To conclude, the disruption of the CARC/CRAC mirror code in the 5th putative transmembrane domain is sufficient to abolish the allosteric interaction between OCT2 and MPP+.
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11
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Gupta A, Kitzler CM, Rathner P, Fahrner M, Grabmayr H, Rathner A, Romanin C, Müller N. Resonance assignment of coiled-coil 3 (CC3) domain of human STIM1. Biomol NMR Assign 2021; 15:433-439. [PMID: 34417953 PMCID: PMC8481183 DOI: 10.1007/s12104-021-10042-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 08/11/2021] [Indexed: 06/13/2023]
Abstract
The protein stromal interaction molecule 1 (STIM1) plays a pivotal role in mediating store-operated calcium entry (SOCE) into cells, which is essential for adaptive immunity. It acts as a calcium sensor in the endoplasmic reticulum (ER) and extends into the cytosol, where it changes from an inactive (tight) to an active (extended) oligomeric form upon calcium store depletion. NMR studies of this protein are challenging due to its membrane-spanning and aggregation properties. Therefore follow the divide-and-conquer approach, focusing on individual domains first is in order. The cytosolic part is predicted to have a large content of coiled-coil (CC) structure. We report the 1H, 13C, 15N chemical shift assignments of the CC3 domain. This domain is crucial for the stabilisation of the tight quiescent form of STIM1 as well as for activating the ORAI calcium channel by direct contact, in the extended active form.
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Affiliation(s)
- Agrim Gupta
- Institute of Organic Chemistry, Johannes Kepler University Linz, Altenbergerstrasse 69, 4040, Linz, Austria
| | - Christian Manuel Kitzler
- Institute of Organic Chemistry, Johannes Kepler University Linz, Altenbergerstrasse 69, 4040, Linz, Austria
| | - Petr Rathner
- Institute of Inorganic Chemistry, Johannes Kepler University Linz, Altenbergerstrasse 69, 4040, Linz, Austria
- Institute of Analytical Chemistry, University of Vienna, Währingerstrasse 38, 1090, Vienna, Austria
| | - Marc Fahrner
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40, 4020, Linz, Austria
| | - Herwig Grabmayr
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40, 4020, Linz, Austria
| | - Adriana Rathner
- Institute of Inorganic Chemistry, Johannes Kepler University Linz, Altenbergerstrasse 69, 4040, Linz, Austria
| | - Christoph Romanin
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40, 4020, Linz, Austria
| | - Norbert Müller
- Institute of Organic Chemistry, Johannes Kepler University Linz, Altenbergerstrasse 69, 4040, Linz, Austria.
- Faculty of Science, University of South Bohemia, Branišovská 1645/31A, 370 05, České Budějovice, Czech Republic.
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12
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Cui Y, Chu F, Yin K, Chen X, Wan H, Luo G, Dong H, Xu F. Role of Serosal TRPV4-Constituted SOCE Mechanism in Secretagogues-Stimulated Intestinal Epithelial Anion Secretion. Front Pharmacol 2021; 12:684538. [PMID: 34335254 PMCID: PMC8317263 DOI: 10.3389/fphar.2021.684538] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 06/24/2021] [Indexed: 12/05/2022] Open
Abstract
As little is known about the role of calcium (Ca2+) signaling mediating the small intestinal epithelial anion secretion, we aimed to study its regulatory role in secretagogue-stimulated duodenal anion secretion and the underlying molecular mechanisms. Therefore, intestinal anion secretion from native mouse duodenal epithelia was examined with Ussing chambers to monitor PGE2-, 5-HT-, and CCh-induced short-circuit currents (Isc). PGE2 (10 μM) and 5-HT (10 μM) induced mouse duodenal Isc, markedly attenuated by serosal Ca2+-free solution and selective blockers of store-operated Ca2+ channels on the serosal side of the duodenum. Furthermore, PGE2- and 5-HT-induced duodenal Isc was also inhibited by ER Ca2+ chelator TPEN. However, dantrolene, a selective blocker of ryanodine receptors, inhibited PGE2-induced duodenal Isc, while LiCl, an inhibitor of IP3 production, inhibited 5-HT-induced Isc. Moreover, duodenal Isc response to the serosal applications of both PGE2 and 5-HT was significantly attenuated in transient receptor potential vanilloid 4 (TRPV4) knockout mice. Finally, mucosal application of carbachol (100 μM) also induced duodenal Isc via selective activation of muscarinic receptors, which was significantly inhibited in serosal Ca2+-free solution but neither in mucosal Ca2+-free solution nor by nifedipine. Therefore, the serosal TRPV4-constituted SOCE mechanism is likely universal for the most common and important secretagogues-induced and Ca2+-dependent intestinal anion secretion. These findings will enhance our knowledge about gastrointestinal (G.I.) epithelial physiology and the associated G.I. diseases, such as diarrhea and constipation.
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Affiliation(s)
- Yinghui Cui
- Department of Pediatric Intensive Care Unit, Children's Hospital of Chongqing Medical University; National Clinical Research Center for Child Health and Disorders; Ministry of Education Key Laboratory of Child Development and Disorders; Chongqing Key Laboratory of Pediatrics, Chongqing, China
| | - Fenglan Chu
- Department of Gastroenterology, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Kai Yin
- Department of Gastroenterology, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Xiongying Chen
- Department of Pediatric Intensive Care Unit, Children's Hospital of Chongqing Medical University; National Clinical Research Center for Child Health and Disorders; Ministry of Education Key Laboratory of Child Development and Disorders; Chongqing Key Laboratory of Pediatrics, Chongqing, China
| | - Hanxing Wan
- Department of Pediatric Intensive Care Unit, Children's Hospital of Chongqing Medical University; National Clinical Research Center for Child Health and Disorders; Ministry of Education Key Laboratory of Child Development and Disorders; Chongqing Key Laboratory of Pediatrics, Chongqing, China
| | - Gang Luo
- Department of Gastroenterology, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Hui Dong
- Department of Pediatric Intensive Care Unit, Children's Hospital of Chongqing Medical University; National Clinical Research Center for Child Health and Disorders; Ministry of Education Key Laboratory of Child Development and Disorders; Chongqing Key Laboratory of Pediatrics, Chongqing, China.,Department of Gastroenterology, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Feng Xu
- Department of Pediatric Intensive Care Unit, Children's Hospital of Chongqing Medical University; National Clinical Research Center for Child Health and Disorders; Ministry of Education Key Laboratory of Child Development and Disorders; Chongqing Key Laboratory of Pediatrics, Chongqing, China
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13
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Salvi A, Skrypnyk C, Da Silva N, Urtizberea JA, Bakhiet M, Robert C, Lévy N, Megarbané A, Delague V, Bartoli M. A novel bi-allelic loss-of-function mutation in STIM1 expands the phenotype of STIM1-related diseases. Clin Genet 2021; 100:84-89. [PMID: 33733462 DOI: 10.1111/cge.13959] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 03/12/2021] [Accepted: 03/16/2021] [Indexed: 11/25/2022]
Abstract
STIM1, the stromal interaction molecule 1, is the key protein for maintaining calcium concentration in the endoplasmic reticulum by triggering the Store Operated Calcium Entry (SOCE). Bi-allelic mutations in STIM1 gene are responsible for a loss-of-function in patients affected with a CRAC channelopathy syndrome in which severe combined immunodeficiency syndrome (SCID-like), autoimmunity, ectodermal dysplasia and muscle hypotonia are combined. Here, we studied two siblings from a consanguineous Syrian family, presenting with muscle weakness, hyperlaxity, elastic skin, tooth abnormalities, dysmorphic facies, hypoplastic patellae and history of respiratory infections. Using exome sequencing, we have identified a new homozygous frameshift mutation in STIM1: c.685delT [p.(Phe229Leufs*12)], leading to a complete loss of STIM1 protein. In this study, we describe an unusual phenotype linked to STIM1 mutations, combining clinical signs usually observed in different STIM1-related diseases. In particular, we confirmed that the complete loss of STIM1 function is not always associated with severe immune disorders. Altogether, our results broaden the spectrum of phenotypes associated with mutations in STIM1 and opens new perspectives on the pathological mechanisms associated with a defect in the proteins constituting the SOCE complex.
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Affiliation(s)
| | - Cristina Skrypnyk
- Al Jawhara Center for Molecular Medicine, Department of Molecular Medicine, College of Medicine and Medical Sciences, Arabian Gulf University, Bahrain
| | | | | | - Moiz Bakhiet
- Al Jawhara Center for Molecular Medicine, Department of Molecular Medicine, College of Medicine and Medical Sciences, Arabian Gulf University, Bahrain
| | | | - Nicolas Lévy
- Aix Marseille Univ, INSERM, MMG, Marseille, France.,AP-HM, Département de Génétique Médicale, Hôpital d'Enfants de la Timone, Marseille, France.,GIPTIS, Genetics Institute for Patients Therapies Innovation and Science, Marseille, France
| | - André Megarbané
- Institut Jérôme Lejeune, Paris, France.,Department of Human Genetics, Gilbert and Rose-Marie Ghagoury School of Medicine, Lebanese American University, Byblos, Lebanon
| | | | - Marc Bartoli
- Aix Marseille Univ, INSERM, MMG, Marseille, France
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14
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Villa T, Jaszczyszyn Y, Libri D. Data from crosslinking and analysis of cDNAs ( CRAC) of Nab3 in yeast cells expressing a circular ncRNA decoy. Data Brief 2021; 35:106951. [PMID: 33842679 PMCID: PMC8020422 DOI: 10.1016/j.dib.2021.106951] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 03/06/2021] [Accepted: 03/08/2021] [Indexed: 11/16/2022] Open
Abstract
Pervasive transcription originating from the ubiquitous activity of RNA Polymerase II (RNAPII) generates a vast mass of non-coding RNAs (ncRNAs) that represent a potential harm to gene expression. In the compact genome of the yeast Saccharomyces cerevisiae, the main genomewide safeguard against pervasive ncRNAs is the Nrd1-Nab3-Sen1 (NNS) complex, composed of two RNA-binding proteins (Nrd1 and Nab3) and the helicase Sen1. The NNS complex directs transcription termination of ncRNA genes and promotes the rapid degradation of pervasive transcripts from yeast nuclei through its physical and functional coupling to the nuclear RNA exosome. We have recently shown that inhibition of the exosome in yeast cells leads to the accumulation of ncRNAs complexed with Nab3 and Nrd1, decreasing recycling of these termination factors to sites of transcription and inducing global termination defects at NNS targets. Consistent with the notion that ncRNAs out-titrate Nab3 and Nrd1 termination factors, we have shown that a similar genomewide termination impairment could be achieved by expressing a circular RNA decoy containing a Nab3 binding target [1]. In relation to this previous research article, here we expand our observations on the effect of the circular RNA decoy on NNS termination. We aimed at verifying that the Nab3 binding sequence present on the decoy is indeed efficiently sequestering Nab3 as intended by design, leading to the expected decrease of Nab3 binding on NNS targets. We employed the crosslinking and cDNA analysis protocol (CRAC) on yeast cells expressing the circular ncRNA decoy or a control construct. We present data from high-resolution genomewide RNA binding of Nab3 in three independent biological replicates of these S.cerevisiae cells, normalized by spiked-in S.pombe lysates. These data allow the useful assessment of the extent of co-transcriptional binding decrease of Nab3 by decoy ncRNA titration and will be valuable for further analyses of NNS targeting mechanisms.
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Affiliation(s)
- Tommaso Villa
- Université de Paris, CNRS, Institut Jacques Monod, F-75006, Paris, France
| | - Yan Jaszczyszyn
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Paris-Saclay University, Gif-sur-Yvette, France
| | - Domenico Libri
- Université de Paris, CNRS, Institut Jacques Monod, F-75006, Paris, France
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15
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Berlansky S, Humer C, Sallinger M, Frischauf I. More Than Just Simple Interaction between STIM and Orai Proteins: CRAC Channel Function Enabled by a Network of Interactions with Regulatory Proteins. Int J Mol Sci 2021; 22:E471. [PMID: 33466526 PMCID: PMC7796502 DOI: 10.3390/ijms22010471] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 12/29/2020] [Accepted: 12/29/2020] [Indexed: 12/27/2022] Open
Abstract
The calcium-release-activated calcium (CRAC) channel, activated by the release of Ca2+ from the endoplasmic reticulum (ER), is critical for Ca2+ homeostasis and active signal transduction in a plethora of cell types. Spurred by the long-sought decryption of the molecular nature of the CRAC channel, considerable scientific effort has been devoted to gaining insights into functional and structural mechanisms underlying this signalling cascade. Key players in CRAC channel function are the Stromal interaction molecule 1 (STIM1) and Orai1. STIM1 proteins span through the membrane of the ER, are competent in sensing luminal Ca2+ concentration, and in turn, are responsible for relaying the signal of Ca2+ store-depletion to pore-forming Orai1 proteins in the plasma membrane. A direct interaction of STIM1 and Orai1 allows for the re-entry of Ca2+ from the extracellular space. Although much is already known about the structure, function, and interaction of STIM1 and Orai1, there is growing evidence that CRAC under physiological conditions is dependent on additional proteins to function properly. Several auxiliary proteins have been shown to regulate CRAC channel activity by means of direct interactions with STIM1 and/or Orai1, promoting or hindering Ca2+ influx in a mechanistically diverse manner. Various proteins have also been identified to exert a modulatory role on the CRAC signalling cascade although inherently lacking an affinity for both STIM1 and Orai1. Apart from ubiquitously expressed representatives, a subset of such regulatory mechanisms seems to allow for a cell-type-specific control of CRAC channel function, considering the rather restricted expression patterns of the specific proteins. Given the high functional and clinical relevance of both generic and cell-type-specific interacting networks, the following review shall provide a comprehensive summary of regulators of the multilayered CRAC channel signalling cascade. It also includes proteins expressed in a narrow spectrum of cells and tissues that are often disregarded in other reviews of similar topics.
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Affiliation(s)
| | | | | | - Irene Frischauf
- Institute of Biophysics, Johannes Kepler University, 4020 Linz, Austria; (S.B.); (C.H.); (M.S.)
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16
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Abstract
Stromal interaction molecules (STIM) are a distinct class of ubiquitously expressed single-pass transmembrane proteins in the endoplasmic reticulum (ER) membrane. Together with Orai ion channels in the plasma membrane (PM), they form the molecular basis of the calcium release-activated calcium (CRAC) channel. An intracellular signaling pathway known as store-operated calcium entry (SOCE) is critically dependent on the CRAC channel. The SOCE pathway is activated by the ligand-induced depletion of the ER calcium store. STIM proteins, acting as calcium sensors, subsequently sense this depletion and activate Orai ion channels via direct physical interaction to allow the influx of calcium ions for store refilling and downstream signaling processes. This review article is dedicated to the latest advances in the field of STIM proteins. New results of ongoing investigations based on the recently published functional data as well as structural data from nuclear magnetic resonance (NMR) spectroscopy and molecular dynamics (MD) simulations are reported and complemented with a discussion of the latest developments in the research of STIM protein isoforms and their differential functions in regulating SOCE.
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Affiliation(s)
| | - Christoph Romanin
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40, 4020 Linz, Austria;
| | - Marc Fahrner
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstrasse 40, 4020 Linz, Austria;
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17
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Abstract
Cancer is caused by excessive cell proliferation and a propensity to avoid cell death, while the spread of cancer is facilitated by enhanced cellular migration, invasion, and vascularization. Cytosolic Ca2+ is central to each of these important processes, yet to date, there are no cancer drugs currently being used clinically, and very few undergoing clinical trials, that target the Ca2+ signalling machinery. The aim of this review is to highlight some of the emerging evidence that targeting key components of the Ca2+ signalling machinery represents a novel and relatively untapped therapeutic strategy for the treatment of cancer.
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Affiliation(s)
- Jason I. E. Bruce
- Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PT, UK
- Correspondence: ; Tel.: +44-(0)-161-275-5484
| | - Andrew D. James
- Department of Biology, University of York, Heslington, York YO10 5DD, UK;
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18
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Abstract
B lymphocytes are an important component of the adaptive and innate immune system because of their ability to secrete antibodies and to present antigens to T cells, which is critical for immune responses to many pathogens. Abnormal B cell function is the cause of diseases including autoimmune, paraneoplastic, and immunodeficiency disorders. The development, survival, and function of B cells depend on signaling through the B cell receptor (BCR) and costimulatory receptors. One of the signaling pathways induced by antigen binding to the BCR is store-operated Ca2+ entry (SOCE), which depends on the Ca2+ channel ORAI1 and its activators stromal interaction molecule (STIM) 1 and 2. A recent study by Berry et al. [1] reports that B cells lacking STIM1 and STIM2 fail to survive and proliferate because abolished SOCE results in impaired expression of two key anti-apoptotic genes and blunted activation of mTORC1 and c-Myc signaling. The associated Ca2+ regulated checkpoints of B cell survival and proliferation can be bypassed, at least partially, by costimulation through CD40 or TLR9. This study provides important new insights on how SOCE controls B cell function.
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Affiliation(s)
- Yin-Hu Wang
- Department of Pathology, New York University School of Medicine, New York, NY, USA
| | - Anthony Y Tao
- Department of Pathology, New York University School of Medicine, New York, NY, USA
| | - Stefan Feske
- Department of Pathology, New York University School of Medicine, New York, NY, USA.
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19
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Niu L, Wu F, Li K, Li J, Zhang SL, Hu J, Wang Q. STIM1 interacts with termini of Orai channels in a sequential manner. J Cell Sci 2020; 133:jcs239491. [PMID: 32107289 DOI: 10.1242/jcs.239491] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 02/24/2020] [Indexed: 12/20/2022] Open
Abstract
Store-operated Ca2+ entry (SOCE) is critical for numerous Ca2+-related processes. The activation of SOCE requires engagement between stromal interaction molecule 1 (STIM1) molecules on the endoplasmic reticulum and Ca2+ release-activated channel (CRAC) Orai on the plasma membrane. However, the molecular details of their interactions remain elusive. Here, we analyzed STIM1-Orai interactions using synthetic peptides derived from the N- and C-termini of Orai channels (Orai-NT and Orai-CT, respectively) and purified fragments of STIM1. The binding of STIM1 to Orai-NT is hydrophilic based, whereas binding to the Orai-CT is mostly hydrophobic. STIM1 decreases its affinity for Orai-CT when Orai-NT is present, supporting a stepwise interaction. Orai3-CT exhibits stronger binding to STIM1 than Orai1-CT, largely due to the shortness of one helical turn. The role of newly identified residues was confirmed by co-immunoprecipitation and Ca2+ imaging using full-length molecules. Our results provide important insight into CRAC gating by STIM1.
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Affiliation(s)
- Liling Niu
- Department of Immunology, School of Basic Medical Sciences, Tianjin Medical University, and Tianjin Key Laboratory of Cellular and Molecular Immunology, Tianjin 300070, China
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Fuyun Wu
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin 300071, China
- School of Basic Medical Sciences, Hubei University of Medicine, Shiyan 442000, China
| | - Kaili Li
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Jing Li
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Shenyuan L Zhang
- Department of Medical Physiology, College of Medicine, Texas A&M Health Science Center, Temple, TX 76504, USA
| | - Junjie Hu
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin 300071, China
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Qian Wang
- Department of Immunology, School of Basic Medical Sciences, Tianjin Medical University, and Tianjin Key Laboratory of Cellular and Molecular Immunology, Tianjin 300070, China
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20
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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21
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Papp F, Hajdu P, Tajti G, Toth A, Nagy E, Fazekas Z, Kovacs S, Vámosi G, Varga Z, Panyi G. Periodic Membrane Potential and Ca 2+ Oscillations in T Cells Forming an Immune Synapse. Int J Mol Sci 2020; 21:ijms21051568. [PMID: 32106594 PMCID: PMC7084896 DOI: 10.3390/ijms21051568] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 02/17/2020] [Accepted: 02/19/2020] [Indexed: 11/25/2022] Open
Abstract
The immunological synapse (IS) is a specialized contact area formed between a T cell and an antigen presenting cell (APC). Besides molecules directly involved in antigen recognition such as the TCR/CD3 complex, ion channels important in the membrane potential and intracellular free Ca2+ concentration control of T cells are also recruited into the IS. These are the voltage-gated Kv1.3 and Ca2+-activated KCa3.1 K+ channels and the calcium release-activated Ca2+ channel (CRAC). However, the consequence of this recruitment on membrane potential and Ca2+ level control is not known. Here we demonstrate that the membrane potential (MP) of murine T cells conjugated with APCs in an IS shows characteristic oscillations. We found that depolarization of the membrane by current injection or by increased extracellular K+ concentration produced membrane potential oscillations (MPO) significantly more frequently in conjugated T cells than in lone T cells. Furthermore, oscillation of the free intracellular Ca2+ concentration could also be observed more frequently in cells forming an IS than in lone cells. We suggest that in the IS the special arrangement of channels and the constrained space between the interacting cells creates a favorable environment for these oscillations, which may enhance the signaling process leading to T cell activation.
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Affiliation(s)
- Ferenc Papp
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary; (F.P.); (G.T.); (A.T.); (E.N.); (Z.F.); (G.V.); (Z.V.)
| | - Peter Hajdu
- Department of Biophysics and Cell Biology, Faculty of Dentistry, University of Debrecen, H-4032 Debrecen, Hungary;
| | - Gabor Tajti
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary; (F.P.); (G.T.); (A.T.); (E.N.); (Z.F.); (G.V.); (Z.V.)
| | - Agnes Toth
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary; (F.P.); (G.T.); (A.T.); (E.N.); (Z.F.); (G.V.); (Z.V.)
| | - Eva Nagy
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary; (F.P.); (G.T.); (A.T.); (E.N.); (Z.F.); (G.V.); (Z.V.)
| | - Zsolt Fazekas
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary; (F.P.); (G.T.); (A.T.); (E.N.); (Z.F.); (G.V.); (Z.V.)
| | - Sandor Kovacs
- Institute of Sectoral Economics and Methodology, Faculty of Economics and Business, Department of Statistics and Research Methodology, University of Debrecen, 4032 Debrecen, Hungary;
| | - György Vámosi
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary; (F.P.); (G.T.); (A.T.); (E.N.); (Z.F.); (G.V.); (Z.V.)
| | - Zoltan Varga
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary; (F.P.); (G.T.); (A.T.); (E.N.); (Z.F.); (G.V.); (Z.V.)
| | - Gyorgy Panyi
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary; (F.P.); (G.T.); (A.T.); (E.N.); (Z.F.); (G.V.); (Z.V.)
- Correspondence: ; Tel.: +36-52-258-603
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22
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Abstract
Although calcium signaling and the important role of calcium release–activated calcium channels is well recognized in the context of immune cell signaling, there is a vast diversity of ion channels and transporters that regulate the entry of ions beyond calcium, including magnesium, zinc, potassium, sodium, and chloride. These ions play a critical role in numerous metabolic and cellular processes. The importance of ions in human health and disease is illustrated by the identification of primary immunodeficiencies in patients with mutations in genes encoding ion channels and transporters, as well as the immunological defects observed in individuals with nutritional ion deficiencies. Despite progress in identifying the important role of ions in immune cell development and activation, we are still in the early stages of exploring the diversity of ion channels and transporters and mechanistically understanding the role of these ions in immune cell biology. Here, we review the biology of ion signaling in B cells and the identification of critical ion channels and transporters in B‐cell development, activation, and differentiation into effector cells. Elucidating the role of ion channels and transporters in immune cell signaling is critical for expanding the repertoire of potential therapeutics for the treatment of immune disorders. Moreover, increased understanding of the role of ions in immune cell function will enhance our understanding of the potentially serious consequences of ion deficiencies in human health and disease.
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Affiliation(s)
- Trisha Mahtani
- Department of Cell & Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | - Bebhinn Treanor
- Department of Cell & Systems Biology, University of Toronto, Toronto, Ontario, Canada.,Department of Biological Sciences, University of Toronto Scarborough, Toronto, Ontario, Canada.,Department of Immunology, University of Toronto, Toronto, Ontario, Canada
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23
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Lopez JJ, Jardin I, Albarrán L, Sanchez-Collado J, Cantonero C, Salido GM, Smani T, Rosado JA. Molecular Basis and Regulation of Store-Operated Calcium Entry. Adv Exp Med Biol 2020; 1131:445-469. [PMID: 31646520 DOI: 10.1007/978-3-030-12457-1_17] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Store-operated Ca2+ entry (SOCE) is a ubiquitous mechanism for Ca2+ influx in mammalian cells with important physiological implications. Since the discovery of SOCE more than three decades ago, the mechanism that communicates the information about the amount of Ca2+ accumulated in the intracellular Ca2+ stores to the plasma membrane channels and the nature of these channels have been matters of intense investigation and debate. The stromal interaction molecule-1 (STIM1) has been identified as the Ca2+ sensor of the intracellular Ca2+ compartments that activates the store-operated channels. STIM1 regulates two types of store-dependent channels: the Ca2+ release-activated Ca2+ (CRAC) channels, formed by Orai1 subunits, that conduct the highly Ca2+ selective current I CRAC and the cation permeable store-operated Ca2+ (SOC) channels, which consist of Orai1 and TRPC1 proteins and conduct the non-selective current I SOC. While the crystal structure of Drosophila CRAC channel has already been solved, the architecture of the SOC channels still remains unclear. The dynamic interaction of STIM1 with the store-operated channels is modulated by a number of proteins that either support the formation of the functional STIM1-channel complex or protect the cell against Ca2+ overload.
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Affiliation(s)
- Jose J Lopez
- Department of Physiology, Cell Physiology Research Group and Institute of Molecular Pathology Biomarkers, University of Extremadura, Cáceres, Spain
| | - Isaac Jardin
- Department of Physiology, Cell Physiology Research Group and Institute of Molecular Pathology Biomarkers, University of Extremadura, Cáceres, Spain.
| | - Letizia Albarrán
- Department of Physiology, Cell Physiology Research Group and Institute of Molecular Pathology Biomarkers, University of Extremadura, Cáceres, Spain
| | - Jose Sanchez-Collado
- Department of Physiology, Cell Physiology Research Group and Institute of Molecular Pathology Biomarkers, University of Extremadura, Cáceres, Spain
| | - Carlos Cantonero
- Department of Physiology, Cell Physiology Research Group and Institute of Molecular Pathology Biomarkers, University of Extremadura, Cáceres, Spain
| | - Gines M Salido
- Department of Physiology, Cell Physiology Research Group and Institute of Molecular Pathology Biomarkers, University of Extremadura, Cáceres, Spain
| | - Tarik Smani
- Department of Medical Physiology and Biophysics and Group of Cardiovascular Pathophysiology, Institute of Biomedicine of Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/University of Sevilla, Sevilla, Spain
| | - Juan A Rosado
- Department of Physiology, Cell Physiology Research Group and Institute of Molecular Pathology Biomarkers, University of Extremadura, Cáceres, Spain
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24
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Fatakia SN, Sarkar P, Chattopadhyay A. A collage of cholesterol interaction motifs in the serotonin 1A receptor: An evolutionary implication for differential cholesterol interaction. Chem Phys Lipids 2019; 221:184-192. [PMID: 30822391 DOI: 10.1016/j.chemphyslip.2019.02.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 02/25/2019] [Accepted: 02/25/2019] [Indexed: 12/22/2022]
Abstract
The serotonin1A receptor is a representative member of the G protein-coupled receptor (GPCR) superfamily and acts as an important drug target. In our previous work, we comprehensively demonstrated that membrane cholesterol is necessary in the organization, dynamics and function of the serotonin1A receptor. In this context, analysis of high-resolution GPCR crystal structures in general and in silico studies of the serotonin1A receptor in particular, have suggested the presence of cholesterol interaction sites (hotspots) in various regions of the receptor. In this work, we have identified an evolutionarily conserved collage of four categories of cholesterol interaction motifs associated with transmembrane helix V and the adjacent intracellular loop 3 fragment of the vertebrate serotonin1A receptor. This collage of motifs represents a total of twenty diverse context-dependent cholesterol interaction configurations. We envision that the gamut of cholesterol interaction sites, characterized by sequence plasticity in cholesterol interaction, could be relevant in receptor-cholesterol interaction in membranes of varying cholesterol content and organization, as found in diverse cell types. We conclude that an evolutionarily conserved mechanism of GPCR-cholesterol interaction allows the serotonin1A receptor to adapt to diverse membrane cholesterol levels during natural evolution.
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Affiliation(s)
- Sarosh N Fatakia
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007, India.
| | - Parijat Sarkar
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007, India
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25
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Cosco J, Regina TMR, Scalise M, Galluccio M, Indiveri C. Regulatory Aspects of the Vacuolar CAT2 Arginine Transporter of S. lycopersicum: Role of Osmotic Pressure and Cations. Int J Mol Sci 2019; 20:E906. [PMID: 30791488 DOI: 10.3390/ijms20040906] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 02/11/2019] [Accepted: 02/15/2019] [Indexed: 12/22/2022] Open
Abstract
Many proteins are localized at the vacuolar membrane, but most of them are still poorly described, due to the inaccessibility of this membrane from the extracellular environment. This work focused on the characterization of the CAT2 transporter from S. lycopersicum (SlCAT2) that was previously overexpressed in E. coli and reconstituted in proteoliposomes for transport assay as [3H]Arg uptake. The orientation of the reconstituted transporter has been attempted and current data support the hypothesis that the protein is inserted in the liposome in the same orientation as in the vacuole. SlCAT2 activity was dependent on the pH, with an optimum at pH 7.5. SlCAT2 transport activity was stimulated by the increase of internal osmolality from 0 to 175 mOsmol while the activity was inhibited by the increase of external osmolality. K+, Na+, and Mg2+ present on the external side of proteoliposomes at physiological concentrations, inhibited the transport activity; differently, the cations had no effect when included in the internal proteoliposome compartment. This data highlighted an asymmetric regulation of SlCAT2. Cholesteryl hemisuccinate, included in the proteoliposomal membrane, stimulated the SlCAT2 transport activity. The homology model of the protein was built using, as a template, the 3D structure of the amino acid transporter GkApcT. Putative substrate binding residues and cholesterol binding domains were proposed. Altogether, the described results open new perspectives for studying the response of SlCAT2 and, in general, of plant vacuolar transporters to metabolic and environmental changes.
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26
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Johnson M, Trebak M. ORAI channels in cellular remodeling of cardiorespiratory disease. Cell Calcium 2019; 79:1-10. [PMID: 30772685 DOI: 10.1016/j.ceca.2019.01.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 01/31/2019] [Accepted: 01/31/2019] [Indexed: 01/08/2023]
Abstract
Cardiorespiratory disease, which includes systemic arterial hypertension, restenosis, atherosclerosis, pulmonary arterial hypertension, asthma, and chronic obstructive pulmonary disease (COPD) are highly prevalent and devastating diseases with limited therapeutic modalities. A common pathophysiological theme to these diseases is cellular remodeling, which is contributed by changes in expression and activation of ion channels critical for either excitability or growth. Calcium (Ca2+) signaling and specifically ORAI Ca2+ channels have emerged as significant regulators of smooth muscle, endothelial, epithelial, platelet, and immune cell remodeling. This review details the dysregulation of ORAI in cardiorespiratory diseases, and how this dysregulation of ORAI contributes to cellular remodeling.
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Affiliation(s)
- Martin Johnson
- Department of Cellular and Molecular Physiology, The Pennsylvania State University College of Medicine, Hershey, PA 17033, United States
| | - Mohamed Trebak
- Department of Cellular and Molecular Physiology, The Pennsylvania State University College of Medicine, Hershey, PA 17033, United States.
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27
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Abstract
A primary calcium (Ca2+) entry pathway into non-excitable cells is through the store-operated Ca2+ release activated Ca2+ (CRAC) channel. Ca2+ entry into cells is responsible for the initiation of diverse signalling cascades that affect essential cellular processes like gene regulation, cell growth and death, secretion and gene transcription. Upon depletion of intracellular Ca2+ stores within the endoplasmic reticulum (ER), the CRAC channel opens to refill depleted stores. The two key limiting molecular players of the CRAC channel are the stromal interaction molecule (STIM1) embedded in the ER-membrane and Orai1, residing in the plasma membrane (PM), respectively. Together, they form a highly Ca2+ selective ion channel complex. STIM1 senses the Ca2+ content of the ER and confers Ca2+ store-depletion into the opening of Orai1 channels in the PM for triggering Ca2+-dependent gene transcription, T-cell activation or mast cell degranulation. The interplay of Orai and STIM proteins in the CRAC channel signalling cascade has been the main focus of research for more than twelve years. This chapter focuses on current knowledge and main experimental advances in the understanding of Orai1 activation by STIM1, thereby portraying key mechanistic steps in the CRAC channel signalling cascade.
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Affiliation(s)
- Victoria Lunz
- Institute of Biophysics, Johannes Kepler University Linz, A-4020, Linz, Austria
| | - Christoph Romanin
- Institute of Biophysics, Johannes Kepler University Linz, A-4020, Linz, Austria.
| | - Irene Frischauf
- Institute of Biophysics, Johannes Kepler University Linz, A-4020, Linz, Austria.
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28
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Bulla M, Gyimesi G, Kim JH, Bhardwaj R, Hediger MA, Frieden M, Demaurex N. ORAI1 channel gating and selectivity is differentially altered by natural mutations in the first or third transmembrane domain. J Physiol 2018; 597:561-582. [PMID: 30382595 PMCID: PMC6332830 DOI: 10.1113/jp277079] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 10/31/2018] [Indexed: 12/12/2022] Open
Abstract
KEY POINTS Gain-of-function mutations in the highly selective Ca2+ channel ORAI1 cause tubular aggregate myopathy (TAM) characterized by muscular pain, weakness and cramping. TAM-associated mutations in ORAI1 first and third transmembrane domain facilitate channel opening by STIM1, causing constitutive Ca2+ influx and increasing the currents evoked by Ca2+ store depletion. Mutation V107M additionally decreases the channel selectivity for Ca2+ ions and its inhibition by acidic pH, while mutation T184M does not alter the channel sensitivity to pH or to reactive oxygen species. The ORAI blocker GSK-7975A prevents the constitutive activity of TAM-associated channels and might be used in therapy for patients suffering from TAM. ABSTRACT Skeletal muscle differentiation relies on store-operated Ca2+ entry (SOCE) mediated by STIM proteins linking the depletion of endoplasmic/sarcoplasmic reticulum Ca2+ stores to the activation of membrane Ca2+ -permeable ORAI channels. Gain-of-function mutations in STIM1 or ORAI1 isoforms cause tubular aggregate myopathy (TAM), a skeletal muscle disorder with muscular pain, weakness and cramping. Here, we characterize two overactive ORAI1 mutants from patients with TAM: V107M and T184M, located in the first and third transmembrane domain of the channel. When ectopically expressed in HEK-293T cells or human primary myoblasts, the mutated channels increased basal and store-operated Ca2+ entry. The constitutive activity of V107M, L138F, T184M and P245L mutants was prevented by low concentrations of GSK-7975A while the G98S mutant was resistant to inhibition. Electrophysiological recordings confirmed ORAI1-V107M constitutive activity and revealed larger STIM1-gated V107M- and T184M-mediated currents with conserved fast and slow Ca2+ -dependent inactivation. Mutation V107M altered the channel selectivity for Ca2+ ions and conferred resistance to acidic inhibition. Ca2+ imaging and molecular dynamics simulations showed a preserved sensitivity of T184M to the negative regulation by reactive oxygen species. Both mutants were able to mediate SOCE in Stim1-/- /Stim2-/- mouse embryonic fibroblasts expressing the binding-deficient STIM1-F394H mutant, indicating a higher sensitivity for STIM1-mediated gating, with ORAI1-T184M gain-of-function being strictly dependent on STIM1. These findings provide new insights into the permeation and regulatory properties of ORAI1 mutants that might translate into therapies against diseases with gain-of-function mutations in ORAI1.
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Affiliation(s)
- M Bulla
- Department of Cell Physiology and Metabolism, University of Geneva, Geneva, Switzerland
| | - G Gyimesi
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland
| | - J H Kim
- Departments of Physiology and Global Medical Science, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea.,Mitohormesis Research Center, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - R Bhardwaj
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland
| | - M A Hediger
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland
| | - M Frieden
- Department of Cell Physiology and Metabolism, University of Geneva, Geneva, Switzerland
| | - N Demaurex
- Department of Cell Physiology and Metabolism, University of Geneva, Geneva, Switzerland
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29
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Zhang X, Spinelli AM, Zhang W, Trebak M. Study of the Endogenous CRAC Channel Using shRNA-Mediated Gene Silencing. Methods Mol Biol 2018; 1843:137-45. [PMID: 30203284 DOI: 10.1007/978-1-4939-8704-7_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
The Ca2+ release-activated Ca2+ (CRAC) current is a major signaling event in non-excitable cells whereby Ca2+ store depletion activates Ca2+ entry across the plasma membrane from the extracellular space. Stromal interaction molecule 1 (STIM1) and Orai1 proteins are the key molecular players of the CRAC channel. Previous studies have linked activity of this channel to many physiological functions, and dysregulation of the CRAC channel has been associated with various diseases. In the absence of inducible tissue-specific knockout mice, in vivo knockdown studies examining the endogenous function of CRAC channel proteins, STIM1 and Orai1, are a challenge. In this chapter, we describe a lentiviral delivery system of shRNA-mediated gene silencing that has proven successful in studying the endogenous CRAC channel in vivo.
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30
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Abstract
Nuclear factor of activated T cells (NFAT) was first described almost three decades ago as a Ca
2+/calcineurin-regulated transcription factor in T cells. Since then, a large body of research uncovered the regulation and physiological function of different NFAT homologues in the immune system and many other tissues. In this review, we will discuss novel roles of NFAT in T cells, focusing mainly on its function in humoral immune responses, immunological tolerance, and the regulation of immune metabolism.
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Affiliation(s)
- Martin Vaeth
- Department of Pathology, New York University School of Medicine, New York, NY, 10016, USA
| | - Stefan Feske
- Department of Pathology, New York University School of Medicine, New York, NY, 10016, USA
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31
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Papanikolaou M, Lewis A, Butt AM. Store-operated calcium entry is essential for glial calcium signalling in CNS white matter. Brain Struct Funct 2017; 222:2993-3005. [PMID: 28247021 PMCID: PMC5585307 DOI: 10.1007/s00429-017-1380-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Accepted: 01/27/2017] [Indexed: 11/06/2022]
Abstract
‘Calcium signalling’ is the ubiquitous response of glial cells to multiple extracellular stimuli. The primary mechanism of glial calcium signalling is by release of calcium from intracellular stores of the endoplasmic reticulum (ER). Replenishment of ER Ca2+ stores relies on store-operated calcium entry (SOCE). However, despite the importance of calcium signalling in glial cells, little is known about their mechanisms of SOCE. Here, we investigated SOCE in glia of the mouse optic nerve, a typical CNS white matter tract that comprises bundles of myelinated axons and the oligodendrocytes and astrocytes that support them. Using quantitative RT-PCR, we identified Orai1 channels, both Stim1 and Stim2, and the transient receptor potential M3 channel (TRPM3) as the primary channels for SOCE in the optic nerve, and their expression in both astrocytes and oligodendrocytes was demonstrated by immunolabelling of optic nerve sections and cultures. The functional importance of SOCE was demonstrated by fluo-4 calcium imaging on isolated intact optic nerves and optic nerve cultures. Removal of extracellular calcium ([Ca2+]o) resulted in a marked depletion of glial cytosolic calcium ([Ca2+]i), which recovered rapidly on restoration of [Ca2+]o via SOCE. 2-aminoethoxydiphenylborane (2APB) significantly decreased SOCE and severely attenuated ATP-mediated calcium signalling. The results provide evidence that Orai/Stim and TRPM3 are important components of the ‘calcium toolkit’ that underpins SOCE and the sustainability of calcium signalling in white matter glia.
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Affiliation(s)
- M Papanikolaou
- Institute of Biomedical and Biomolecular Sciences, School of Pharmacy and Biomedical Science, University of Portsmouth, Portsmouth, PO1 2DT, UK
| | - A Lewis
- Institute of Biomedical and Biomolecular Sciences, School of Pharmacy and Biomedical Science, University of Portsmouth, Portsmouth, PO1 2DT, UK
| | - A M Butt
- Institute of Biomedical and Biomolecular Sciences, School of Pharmacy and Biomedical Science, University of Portsmouth, Portsmouth, PO1 2DT, UK.
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32
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Charles E, Hammadi M, Kischel P, Delcroix V, Demaurex N, Castelbou C, Vacher AM, Devin A, Ducret T, Nunes P, Vacher P. The antidepressant fluoxetine induces necrosis by energy depletion and mitochondrial calcium overload. Oncotarget 2017; 8:3181-3196. [PMID: 27911858 PMCID: PMC5356874 DOI: 10.18632/oncotarget.13689] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 11/21/2016] [Indexed: 11/25/2022] Open
Abstract
Selective Serotonin Reuptake Inhibitor antidepressants, such as fluoxetine (Prozac), have been shown to induce cell death in cancer cells, paving the way for their potential use as cancer therapy. These compounds are able to increase cytosolic calcium concentration ([Ca2+]cyt), but the involved mechanisms and their physiological consequences are still not well understood. Here, we show that fluoxetine induces an increase in [Ca2+]cyt by emptying the endoplasmic reticulum (ER) through the translocon, an ER Ca2+ leakage structure. Our data also show that fluoxetine inhibits oxygen consumption and lowers mitochondrial ATP. This latter is essential for Ca2+ reuptake into the ER, and we postulated therefore that the fluoxetine-induced decrease in mitochondrial ATP production results in the emptying of the ER, leading to capacitative calcium entry. Furthermore, Ca2+ quickly accumulated in the mitochondria, leading to mitochondrial Ca2+ overload and cell death. We found that fluoxetine could induce an early necrosis in human peripheral blood lymphocytes and Jurkat cells, and could also induce late apoptosis, especially in the tumor cell line. These results shed light on fluoxetine-induced cell death and its potential use in cancer treatment.
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Affiliation(s)
- Emilie Charles
- INSERM U1218, Institut Bergonié, Bordeaux, France
- Université de Bordeaux, Bordeaux, France
| | - Mehdi Hammadi
- INSERM U1218, Institut Bergonié, Bordeaux, France
- Université de Bordeaux, Bordeaux, France
| | - Philippe Kischel
- Laboratory of Cellular and Molecular Physiology EA4667, Université de Picardie Jules Verne, SFR CAP-SANTE (FED 4231), Amiens, France
| | - Vanessa Delcroix
- INSERM U1218, Institut Bergonié, Bordeaux, France
- Université de Bordeaux, Bordeaux, France
| | - Nicolas Demaurex
- Department of Cell Physiology and Metabolism, University of Geneva, Geneva, Switzerland
| | - Cyril Castelbou
- Department of Cell Physiology and Metabolism, University of Geneva, Geneva, Switzerland
| | - Anne-Marie Vacher
- INSERM U1218, Institut Bergonié, Bordeaux, France
- Université de Bordeaux, Bordeaux, France
| | - Anne Devin
- Institut de Biochimie et Génétique Cellulaires, UMR 5095, Bordeaux, France
- Université de Bordeaux, Bordeaux, France
| | - Thomas Ducret
- INSERM U1045, Centre de Recherche Cardio-Thoracique, Bordeaux, France
- Université de Bordeaux, Bordeaux, France
| | - Paula Nunes
- Department of Cell Physiology and Metabolism, University of Geneva, Geneva, Switzerland
| | - Pierre Vacher
- INSERM U1218, Institut Bergonié, Bordeaux, France
- Université de Bordeaux, Bordeaux, France
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33
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Abstract
Cysteines are among the least abundant amino acids found in proteins. Due to their unique nucleophilic thiol group, they are able to undergo a broad range of chemical modifications besides their known role in disulfide formation, such as S-sulfenylation (-SOH), S-sulfinylation (-SO(2)H), S-sufonylation (-SO(3)H), S-glutathionylation (-SSG), and S-sulfhydration (-SSH), among others. These posttranslational modifications can be irreversible and act as transitional modifiers or as reversible on-off switches for the function of proteins. Disturbances of the redox homeostasis, for example, in situations of increased oxidative stress, can contribute to a range of diseases. Because Ca2+ signaling mediated by store-operated calcium entry (SOCE) is involved in a plethora of cellular responses, the cross-talk between reactive oxygen species (ROS) and Ca2+ is critical for homeostatic control. Identification of calcium regulatory protein targets of thiol redox modifications is needed to understand their role in biology and disease.
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Affiliation(s)
- Barbara A Niemeyer
- Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine, Saarland University, Homburg, Germany.
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34
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Abstract
Several crosslinking methods have been developed to identify interacting RNAs for proteins of interest. Here, we describe variants of the UV crosslinking and analysis of cDNA (CRAC) method that allow target identification of RNA methyltransferases on a genome-wide scale. We present a detailed protocol for the application of CRAC in human cells that stably express the protein of interest fused to a tandem affinity tag. After the introduction of a covalent link between the protein and its target RNAs, protein-RNA complexes are purified and bound RNAs trimmed, ligated to adapters, reverse transcribed, and amplified. Sequences obtained from next-generation sequencing are then mapped onto the human genome allowing the identification of possible substrates. For some RNA methyltransferases, e.g., m5C MTases, their catalytic mechanism can be exploited for chemical crosslinking approaches instead of UV based crosslinking.
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Affiliation(s)
- Sara Haag
- Centre for Biochemistry and Molecular Cell Biology, Institute for Molecular Biology, Georg-August-University, Humboldtallee 23, 37073, Göttingen, Germany
| | - Jens Kretschmer
- Centre for Biochemistry and Molecular Cell Biology, Institute for Molecular Biology, Georg-August-University, Humboldtallee 23, 37073, Göttingen, Germany
| | - Katherine E Sloan
- Centre for Biochemistry and Molecular Cell Biology, Institute for Molecular Biology, Georg-August-University, Humboldtallee 23, 37073, Göttingen, Germany
| | - Markus T Bohnsack
- Centre for Biochemistry and Molecular Cell Biology, Institute for Molecular Biology, Georg-August-University, Humboldtallee 23, 37073, Göttingen, Germany. .,Göttingen Centre for Molecular Biosciences, Georg-August-University, 37073, Göttingen, Germany.
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35
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Waters SA, McAteer SP, Kudla G, Pang I, Deshpande NP, Amos TG, Leong KW, Wilkins MR, Strugnell R, Gally DL, Tollervey D, Tree JJ. Small RNA interactome of pathogenic E. coli revealed through crosslinking of RNase E. EMBO J 2016; 36:374-387. [PMID: 27836995 PMCID: PMC5286369 DOI: 10.15252/embj.201694639] [Citation(s) in RCA: 125] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 10/06/2016] [Accepted: 10/11/2016] [Indexed: 02/04/2023] Open
Abstract
RNA sequencing studies have identified hundreds of non‐coding RNAs in bacteria, including regulatory small RNA (sRNA). However, our understanding of sRNA function has lagged behind their identification due to a lack of tools for the high‐throughput analysis of RNA–RNA interactions in bacteria. Here we demonstrate that in vivo sRNA–mRNA duplexes can be recovered using UV‐crosslinking, ligation and sequencing of hybrids (CLASH). Many sRNAs recruit the endoribonuclease, RNase E, to facilitate processing of mRNAs. We were able to recover base‐paired sRNA–mRNA duplexes in association with RNase E, allowing proximity‐dependent ligation and sequencing of cognate sRNA–mRNA pairs as chimeric reads. We verified that this approach captures bona fide sRNA–mRNA interactions. Clustering analyses identified novel sRNA seed regions and sets of potentially co‐regulated target mRNAs. We identified multiple mRNA targets for the pathotype‐specific sRNA Esr41, which was shown to regulate colicin sensitivity and iron transport in E. coli. Numerous sRNA interactions were also identified with non‐coding RNAs, including sRNAs and tRNAs, demonstrating the high complexity of the sRNA interactome.
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Affiliation(s)
- Shafagh A Waters
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Sean P McAteer
- The Roslin Institute, University of Edinburgh, Edinburgh, UK
| | - Grzegorz Kudla
- MRC Human Genetic Unit, University of Edinburgh, Edinburgh, UK
| | - Ignatius Pang
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, Australia.,Systems Biology Initiative, University of New South Wales, Sydney, NSW, Australia
| | - Nandan P Deshpande
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, Australia.,Systems Biology Initiative, University of New South Wales, Sydney, NSW, Australia
| | - Timothy G Amos
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Kai Wen Leong
- Peter Doherty Institute, University of Melbourne, Melbourne, Victoria, Australia
| | - Marc R Wilkins
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, Australia.,Systems Biology Initiative, University of New South Wales, Sydney, NSW, Australia
| | - Richard Strugnell
- Peter Doherty Institute, University of Melbourne, Melbourne, Victoria, Australia
| | - David L Gally
- The Roslin Institute, University of Edinburgh, Edinburgh, UK
| | - David Tollervey
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh, UK
| | - Jai J Tree
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, Australia
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36
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Pydi SP, Jafurulla M, Wai L, Bhullar RP, Chelikani P, Chattopadhyay A. Cholesterol modulates bitter taste receptor function. Biochim Biophys Acta 2016; 1858:2081-7. [PMID: 27288892 DOI: 10.1016/j.bbamem.2016.06.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 06/02/2016] [Accepted: 06/07/2016] [Indexed: 11/20/2022]
Abstract
Bitter taste perception in humans is believed to act as a defense mechanism against ingestion of potential toxic substances. Bitter taste is perceived by 25 distinct bitter taste receptors (T2Rs) which belong to the family of G protein-coupled receptors (GPCRs). In the overall context of the role of membrane lipids in GPCR function, we show here that T2R4, a representative member of the bitter taste receptor family, displays cholesterol sensitivity in its signaling function. In order to gain further insight into cholesterol sensitivity of T2R4, we mutated two residues Tyr114(3.59) and Lys117(3.62) present in the cholesterol recognition amino acid consensus (CRAC) motif in T2R4 with alanines. We carried out functional characterization of the mutants by calcium mobilization, followed by cholesterol depletion and replenishment. CRAC motifs in GPCRs have previously been implicated in preferential cholesterol association. Our analysis shows that the CRAC motif represents an intrinsic feature of bitter taste receptors and is conserved in 22 out of 25 human T2Rs. We further demonstrate that Lys117, an important CRAC residue, is crucial in the reported cholesterol sensitivity of T2R4. Interestingly, cholesterol sensitivity of T2R4 was observed at quinine concentrations in the lower mM range. To the best of our knowledge, our results represent the first report addressing the molecular basis of cholesterol sensitivity in the function of taste receptors.
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37
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Kumar GA, Jafurulla M, Chattopadhyay A. The membrane as the gatekeeper of infection: Cholesterol in host-pathogen interaction. Chem Phys Lipids 2016; 199:179-185. [PMID: 26902688 DOI: 10.1016/j.chemphyslip.2016.02.007] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2016] [Revised: 02/13/2016] [Accepted: 02/15/2016] [Indexed: 11/30/2022]
Abstract
The cellular plasma membrane serves as a portal for the entry of intracellular pathogens. An essential step for an intracellular pathogen to gain entry into a host cell therefore is to be able to cross the cell membrane. In this review, we highlight the role of host membrane cholesterol in regulating the entry of intracellular pathogens using insights obtained from work on the interaction of Leishmania and Mycobacterium with host cells. The entry of these pathogens is known to be dependent on host membrane cholesterol. Importantly, pathogen entry is inhibited either upon depletion (or complexation), or enrichment of membrane cholesterol. In other words, an optimum level of host membrane cholesterol is necessary for efficient infection by pathogens. In this overall context, we propose a general mechanism, based on cholesterol-induced conformational changes, involving cholesterol binding sites in host cell surface receptors that are implicated in this process. A therapeutic strategy targeting modulation of membrane cholesterol would have the advantage of avoiding the commonly encountered problem of drug resistance in tackling infection by intracellular pathogens. Insights into the role of host membrane cholesterol in pathogen entry would be instrumental in the development of novel therapeutic strategies to effectively tackle intracellular pathogenesis.
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Affiliation(s)
- G Aditya Kumar
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007, India
| | - Md Jafurulla
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007, India
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38
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Abstract
Ion channels and transporters mediate the transport of charged ions across hydrophobic lipid membranes. In immune cells, divalent cations such as calcium, magnesium, and zinc have important roles as second messengers to regulate intracellular signaling pathways. By contrast, monovalent cations such as sodium and potassium mainly regulate the membrane potential, which indirectly controls the influx of calcium and immune cell signaling. Studies investigating human patients with mutations in ion channels and transporters, analysis of gene-targeted mice, or pharmacological experiments with ion channel inhibitors have revealed important roles of ionic signals in lymphocyte development and in innate and adaptive immune responses. We here review the mechanisms underlying the function of ion channels and transporters in lymphocytes and innate immune cells and discuss their roles in lymphocyte development, adaptive and innate immune responses, and autoimmunity, as well as recent efforts to develop pharmacological inhibitors of ion channels for immunomodulatory therapy.
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39
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Pinto MCX, Kihara AH, Goulart VAM, Tonelli FMP, Gomes KN, Ulrich H, Resende RR. Calcium signaling and cell proliferation. Cell Signal 2015; 27:2139-49. [PMID: 26275497 DOI: 10.1016/j.cellsig.2015.08.006] [Citation(s) in RCA: 129] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Revised: 08/04/2015] [Accepted: 08/10/2015] [Indexed: 12/17/2022]
Abstract
Cell proliferation is orchestrated through diverse proteins related to calcium (Ca(2+)) signaling inside the cell. Cellular Ca(2+) influx that occurs first by various mechanisms at the plasma membrane, is then followed by absorption of Ca(2+) ions by mitochondria and endoplasmic reticulum, and, finally, there is a connection of calcium stores to the nucleus. Experimental evidence indicates that the fluctuation of Ca(2+) from the endoplasmic reticulum provides a pivotal and physiological role for cell proliferation. Ca(2+) depletion in the endoplasmatic reticulum triggers Ca(2+) influx across the plasma membrane in an phenomenon called store-operated calcium entries (SOCEs). SOCE is activated through a complex interplay between a Ca(2+) sensor, denominated STIM, localized in the endoplasmic reticulum and a Ca(2+) channel at the cell membrane, denominated Orai. The interplay between STIM and Orai proteins with cell membrane receptors and their role in cell proliferation is discussed in this review.
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Affiliation(s)
- Mauro Cunha Xavier Pinto
- Departamento de Bioquímica e Imunologia, Instituto de Ciência Biológicas, Univtreersidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, 31270-901 Belo Horizonte, MG, Brazil; Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, Av. Prof. Lineu Presyes 748, 05508-000 São Paulo, SP, Brazil; Instituto Nanocell, Rua Santo Antônio, 420, 35500-041 Divinópolis, MG, Brazil
| | - Alexandre Hiroaki Kihara
- Universidade Federal do ABC, Centro de Matemática, Computação e Cognição, Rua Arcturus (Jd Antares), 09606-070, São Bernardo do Campo, SP, Brazil
| | - Vânia A M Goulart
- Departamento de Bioquímica e Imunologia, Instituto de Ciência Biológicas, Univtreersidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, 31270-901 Belo Horizonte, MG, Brazil; Instituto Nanocell, Rua Santo Antônio, 420, 35500-041 Divinópolis, MG, Brazil
| | - Fernanda M P Tonelli
- Departamento de Bioquímica e Imunologia, Instituto de Ciência Biológicas, Univtreersidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, 31270-901 Belo Horizonte, MG, Brazil; Instituto Nanocell, Rua Santo Antônio, 420, 35500-041 Divinópolis, MG, Brazil
| | - Katia N Gomes
- Departamento de Bioquímica e Imunologia, Instituto de Ciência Biológicas, Univtreersidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, 31270-901 Belo Horizonte, MG, Brazil
| | - Henning Ulrich
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, Av. Prof. Lineu Presyes 748, 05508-000 São Paulo, SP, Brazil
| | - Rodrigo R Resende
- Departamento de Bioquímica e Imunologia, Instituto de Ciência Biológicas, Univtreersidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, 31270-901 Belo Horizonte, MG, Brazil; Instituto Nanocell, Rua Santo Antônio, 420, 35500-041 Divinópolis, MG, Brazil.
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40
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Abstract
Stromal interaction molecules (STIM) 1 and 2 are sensors of the calcium concentration in the endoplasmic reticulum. Depletion of endoplasmic reticulum calcium stores activates STIM proteins which, in turn, bind and open calcium channels in the plasma membrane formed by the proteins ORAI1, ORAI2, and ORAI3. The resulting store-operated calcium entry (SOCE), mostly controlled by the principal components STIM1 and ORAI1, has been particularly characterized in immune cells. In the nervous system, all STIM and ORAI homologs are expressed. This review summarizes current knowledge on distribution and function of STIM and ORAI proteins in central neurons and glial cells, i.e. astrocytes and microglia. STIM2 is required for SOCE in hippocampal synapses and cortical neurons, whereas STIM1 controls calcium store replenishment in cerebellar Purkinje neurons. In microglia, STIM1, STIM2, and ORAI1 regulate migration and phagocytosis. The isoforms ORAI2 and ORAI3 are candidates for SOCE channels in neurons and astrocytes, respectively. Due to the role of SOCE in neuronal and glial calcium homeostasis, dysfunction of STIM and ORAI proteins may have consequences for the development of neurodegenerative disorders, such as Alzheimer's disease.
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Affiliation(s)
- Robert Kraft
- a Carl-Ludwig-Institute for Physiology, University of Leipzig ; Leipzig , Germany
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41
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Midzak AS, Akula N, Rone MB, Papadopoulos V. Computational modeling and biological validation of novel non-steroidal ligands for the cholesterol recognition/interaction amino acid consensus ( CRAC) motif of the mitochondrial translocator protein (TSPO). Pharmacol Res 2015; 99:393-403. [PMID: 25936508 DOI: 10.1016/j.phrs.2015.03.023] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2014] [Revised: 03/27/2015] [Accepted: 03/27/2015] [Indexed: 01/24/2023]
Abstract
Mitochondria play a critical role in the physiological homeostasis of the cell, contributing to numerous cellular processes, including bioenergetics, metabolism and cell life and death. Owing to their keystone role, mitochondria have gained much attention as pharmacological targets. The outer mitochondrial integral membrane translocator protein (TSPO) has attracted a significant degree of pharmacological interest owing to its ability to bind a number of classes of drugs with high affinity and specificity. In addition to its well-characterized drug binding site, TSPO possess an additional high-affinity ligand binding site, originally identified for its ability to bind the lipid cholesterol, which was named the cholesterol recognition/interaction amino acid consensus (CRAC) motif. Previous investigations from our laboratory identified additional ligands targeted to TSPO's CRAC motif which are able to potently inhibit mitochondrial cholesterol transport and steroid biosynthesis, processes for which TSPO has been well-characterized. However, all of these compounds possessed the steroidal backbone common to cholesterol and steroid hormones. In our efforts to expand our understanding of TSPO's CRAC motif, we performed studies aimed at identifying non-steroidal ligands for this motif. Molecular modeling and in silico screening of large chemical libraries identified a panel of compounds which were subsequently screened for bioactivity in a number of steroidogenic model systems. These efforts identified a family of non-steroidal CRAC ligands able to potently inhibit steroidogenesis, and at higher concentrations, promote apoptosis. In addition, the best candidate in this family was able to suppress testosterone synthesis when administered to rats, indicating that this novel family of non-steroidal CRAC ligands may serve as prototypes for the development of drugs useful for treatment of diseases of steroid overproduction, such as Cushing's syndrome and steroidogenic cell tumors in humans and animals.
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Affiliation(s)
- Andrew S Midzak
- The Research Institute of the McGill University Health Centre and Department of Medicine, McGill University, Montreal, Quebec, Canada
| | - Nagaraju Akula
- The Research Institute of the McGill University Health Centre and Department of Medicine, McGill University, Montreal, Quebec, Canada
| | - Malena B Rone
- The Research Institute of the McGill University Health Centre and Department of Medicine, McGill University, Montreal, Quebec, Canada
| | - Vassilios Papadopoulos
- The Research Institute of the McGill University Health Centre and Department of Medicine, McGill University, Montreal, Quebec, Canada; Departments of Biochemistry and Pharmacology & Therapeutics, McGill University, Montreal, Quebec, Canada.
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Ruysschaert JM, Lonez C. Role of lipid microdomains in TLR-mediated signalling. Biochim Biophys Acta 2015; 1848:1860-7. [PMID: 25797518 DOI: 10.1016/j.bbamem.2015.03.014] [Citation(s) in RCA: 90] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Revised: 03/09/2015] [Accepted: 03/12/2015] [Indexed: 12/13/2022]
Abstract
Over the last twenty years, evidence has been provided that the plasma membrane is partitioned with microdomains, laterally mobile in the bilayer, providing the necessary microenvironment to specific membrane proteins for signalling pathways to be initiated. We discuss here the importance of such microdomains for Toll-like receptors (TLR) localization and function. First, lipid microdomains favour recruitment and clustering of the TLR machinery partners, i.e. receptors and co-receptors previously identified to be required for ligand recognition and signal transmission. Further, the presence of the so-called Cholesterol Recognition Amino-Acid Consensus (CRAC) sequences in the intracellular juxtamembrane domain of several Toll-like receptors suggests a direct role of cholesterol in the activation process. This article is part of a Special Issue entitled: Lipid-protein interactions.
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Affiliation(s)
- Jean-Marie Ruysschaert
- Structure and Function of Biological Membranes, Université Libre de Bruxelles, Boulevard du Triomphe, 1050 Brussels, Belgium
| | - Caroline Lonez
- Structure and Function of Biological Membranes, Université Libre de Bruxelles, Boulevard du Triomphe, 1050 Brussels, Belgium; Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES, United Kingdom.
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Alansary D, Bogeski I, Niemeyer BA. Facilitation of Orai3 targeting and store-operated function by Orai1. Biochim Biophys Acta 2015; 1853:1541-50. [PMID: 25791427 DOI: 10.1016/j.bbamcr.2015.03.007] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Revised: 03/04/2015] [Accepted: 03/10/2015] [Indexed: 11/27/2022]
Abstract
Orai1 subunits interacting with STIM1 molecules comprise the major components responsible for calcium release-activated calcium (CRAC) channels. The homologs Orai2 and Orai3 yield smaller store-operated currents when overexpressed and are mostly unable to substitute Orai1. Orai3 subunits are also essential components of store independent channel complexes and also tune inhibition of ICRAC by reactive oxygen species. Here we use patch-clamp, microscopy, Ca(2+)-imaging and biochemical experiments to investigate the interdependence of Orai2, Orai3 and Orai1. We demonstrate that store-operation and localization of Orai3 but not of Orai2 to STIM1 clusters in HEK cells or to the immunological synapse in T cells is facilitated by Orai1 while Orai3's store-independent activity remains unaffected. On the other hand, one Orai3 subunit confers redox-resistance to heteromeric channels. The inefficient store operation of Orai3 is partly due to the lack of three critical C-terminal residues, the insertion of which improves interaction with STIM1 and abrogates Orai3's dependence on Orai1. Our results suggest that Orai3 down-tunes efficient STIM1 gating when in a heteromeric complex with Orai1.
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Affiliation(s)
- Dalia Alansary
- Molecular Biophysics, School of Medicine, Saarland University, 66421 Homburg, Germany
| | - Ivan Bogeski
- Biophysics, Center for Integrated Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, 66421 Homburg, Germany
| | - Barbara A Niemeyer
- Molecular Biophysics, School of Medicine, Saarland University, 66421 Homburg, Germany.
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Guzman R, Valente EG, Pretorius J, Pacheco E, Qi M, Bennett BD, Fong DH, Lin FF, Bi V, McBride HJ. Expression of ORAII, a plasma membrane resident subunit of the CRAC channel, in rodent and non-rodent species. J Histochem Cytochem 2014; 62:864-78. [PMID: 25249026 DOI: 10.1369/0022155414554926] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
We determined the expression of ORAI1 protein in rodent and non-rodent tissues using a monoclonal antibody directed against an extracellular loop of the protein. Previous reports using antibodies directed at the C-terminus of ORAI1 have not detected central nervous system (CNS) expression. Our results demonstrate broad tissue expression that includes the CNS using a unique monoclonal antibody specific to an extracellular loop of ORAI1. In addition, we present in situ hybridization (ISH) results using a probe within the middle of the mouse coding region showing CNS expression of Orai1 RNA. We contrast the patterns of rodent and human tissue expression and conclude that rodents have similar expression of ORAI1 in most tissue types when compared to primates, with an important exception being the male reproductive system, where human-specific expression is observed.
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Affiliation(s)
- Roberto Guzman
- Departments of Pathology (RG, EGV, JP, EP, MQ), Amgen, Inc. Thousand Oaks, CaliforniaTherapeutic Discovery (FFL, VB), Amgen, Inc. Thousand Oaks, CaliforniaDiscovery Toxicology (HJM), Amgen, Inc. Thousand Oaks, CaliforniaInflammation Research (BDB, DHF), Amgen, Inc. Thousand Oaks, California
| | - Eliane G Valente
- Departments of Pathology (RG, EGV, JP, EP, MQ), Amgen, Inc. Thousand Oaks, CaliforniaTherapeutic Discovery (FFL, VB), Amgen, Inc. Thousand Oaks, CaliforniaDiscovery Toxicology (HJM), Amgen, Inc. Thousand Oaks, CaliforniaInflammation Research (BDB, DHF), Amgen, Inc. Thousand Oaks, California
| | - Jim Pretorius
- Departments of Pathology (RG, EGV, JP, EP, MQ), Amgen, Inc. Thousand Oaks, CaliforniaTherapeutic Discovery (FFL, VB), Amgen, Inc. Thousand Oaks, CaliforniaDiscovery Toxicology (HJM), Amgen, Inc. Thousand Oaks, CaliforniaInflammation Research (BDB, DHF), Amgen, Inc. Thousand Oaks, California
| | - Efrain Pacheco
- Departments of Pathology (RG, EGV, JP, EP, MQ), Amgen, Inc. Thousand Oaks, CaliforniaTherapeutic Discovery (FFL, VB), Amgen, Inc. Thousand Oaks, CaliforniaDiscovery Toxicology (HJM), Amgen, Inc. Thousand Oaks, CaliforniaInflammation Research (BDB, DHF), Amgen, Inc. Thousand Oaks, California
| | - Meiying Qi
- Departments of Pathology (RG, EGV, JP, EP, MQ), Amgen, Inc. Thousand Oaks, CaliforniaTherapeutic Discovery (FFL, VB), Amgen, Inc. Thousand Oaks, CaliforniaDiscovery Toxicology (HJM), Amgen, Inc. Thousand Oaks, CaliforniaInflammation Research (BDB, DHF), Amgen, Inc. Thousand Oaks, California
| | - Brian D Bennett
- Departments of Pathology (RG, EGV, JP, EP, MQ), Amgen, Inc. Thousand Oaks, CaliforniaTherapeutic Discovery (FFL, VB), Amgen, Inc. Thousand Oaks, CaliforniaDiscovery Toxicology (HJM), Amgen, Inc. Thousand Oaks, CaliforniaInflammation Research (BDB, DHF), Amgen, Inc. Thousand Oaks, California
| | - David H Fong
- Departments of Pathology (RG, EGV, JP, EP, MQ), Amgen, Inc. Thousand Oaks, CaliforniaTherapeutic Discovery (FFL, VB), Amgen, Inc. Thousand Oaks, CaliforniaDiscovery Toxicology (HJM), Amgen, Inc. Thousand Oaks, CaliforniaInflammation Research (BDB, DHF), Amgen, Inc. Thousand Oaks, California
| | - Fen-Fen Lin
- Departments of Pathology (RG, EGV, JP, EP, MQ), Amgen, Inc. Thousand Oaks, CaliforniaTherapeutic Discovery (FFL, VB), Amgen, Inc. Thousand Oaks, CaliforniaDiscovery Toxicology (HJM), Amgen, Inc. Thousand Oaks, CaliforniaInflammation Research (BDB, DHF), Amgen, Inc. Thousand Oaks, California
| | - Vivian Bi
- Departments of Pathology (RG, EGV, JP, EP, MQ), Amgen, Inc. Thousand Oaks, CaliforniaTherapeutic Discovery (FFL, VB), Amgen, Inc. Thousand Oaks, CaliforniaDiscovery Toxicology (HJM), Amgen, Inc. Thousand Oaks, CaliforniaInflammation Research (BDB, DHF), Amgen, Inc. Thousand Oaks, California
| | - Helen J McBride
- Departments of Pathology (RG, EGV, JP, EP, MQ), Amgen, Inc. Thousand Oaks, CaliforniaTherapeutic Discovery (FFL, VB), Amgen, Inc. Thousand Oaks, CaliforniaDiscovery Toxicology (HJM), Amgen, Inc. Thousand Oaks, CaliforniaInflammation Research (BDB, DHF), Amgen, Inc. Thousand Oaks, California
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Gaida K, Salimi-Moosavi H, Subramanian R, Almon V, Knize A, Zhang M, Lin FF, Nguyen HQ, Zhou L, Sullivan JK, Wong M, McBride HJ. Inhibition of CRAC with a human anti-ORAI1 monoclonal antibody inhibits T-cell-derived cytokine production but fails to inhibit a T-cell-dependent antibody response in the cynomolgus monkey. J Immunotoxicol 2014; 12:164-73. [PMID: 24990272 DOI: 10.3109/1547691x.2014.915897] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
ORAI1 is the pore-forming component of calcium release-activated calcium (CRAC) channels. CRAC channels are the primary route for calcium ion (Ca(2+)) entry into T-cells following antigen stimulation. This Ca(2+) entry induces proliferation and cytokine production through activation of calcineurin and the nuclear factor of activated T-cells (NFAT) transcription factor along with subsequent cytokine-related genes. It was hypothesized that the in vivo inhibition of T-cell function by blocking ORAI1 or calcineurin would lead to similar functional consequences. To test this hypothesis the activity of 2C1.1, a fully human anti-ORAI1 monoclonal antibody, and cyclosporin A (CsA) were tested in vivo for their suppressive effect on T-cell-derived cytokine production and a T-cell-dependent antibody response (TDAR) using sheep red blood cells (SRBC) in cynomolgus monkeys. Despite showing similar inhibition of ex vivo interleukin (IL)-2 production by stimulated T-cells, both molecules exhibited different pharmacologic effects on the SRBC antibody response. CsA blocked the development of SRBC-specific antibodies, while 2C1.1 failed to inhibit the antigen-specific antibody response. These surprising observations suggest that full inhibition of the CRAC channel is required to inhibit a functional immune response, consistent with findings from human patients with loss of function mutations in ORAI1.
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Misceo D, Holmgren A, Louch WE, Holme PA, Mizobuchi M, Morales RJ, De Paula AM, Stray-Pedersen A, Lyle R, Dalhus B, Christensen G, Stormorken H, Tjønnfjord GE, Frengen E. A dominant STIM1 mutation causes Stormorken syndrome. Hum Mutat 2014; 35:556-64. [PMID: 24619930 DOI: 10.1002/humu.22544] [Citation(s) in RCA: 122] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2014] [Accepted: 03/04/2014] [Indexed: 12/11/2022]
Abstract
Stormorken syndrome is a rare autosomal-dominant disease with mild bleeding tendency, thrombocytopathy, thrombocytopenia, mild anemia, asplenia, tubular aggregate myopathy, miosis, headache, and ichthyosis. A heterozygous missense mutation in STIM1 exon 7 (c.910C>T; p.Arg304Trp) (NM_003156.3) was found to segregate with the disease in six Stormorken syndrome patients in four families. Upon sensing Ca(2+) depletion in the endoplasmic reticulum lumen, STIM1 undergoes a conformational change enabling it to interact with and open ORAI1, a Ca(2+) release-activated Ca(2+) channel located in the plasma membrane. The STIM1 mutation found in Stormorken syndrome patients is located in the coiled-coil 1 domain, which might play a role in keeping STIM1 inactive. In agreement with a possible gain-of-function mutation in STIM1, blood platelets from patients were in a preactivated state with high exposure of aminophospholipids on the outer surface of the plasma membrane. Resting Ca(2+) levels were elevated in platelets from the patients compared with controls, and store-operated Ca(2+) entry was markedly attenuated, further supporting constitutive activity of STIM1 and ORAI1. Thus, our data are compatible with a near-maximal activation of STIM1 in Stormorken syndrome patients. We conclude that the heterozygous mutation c.910C>T causes the complex phenotype that defines this syndrome.
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Affiliation(s)
- Doriana Misceo
- Department of Medical Genetics, University of Oslo and Oslo University Hospital, Oslo, Norway
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47
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Harraz OF, Altier C. STIM1-mediated bidirectional regulation of Ca(2+) entry through voltage-gated calcium channels (VGCC) and calcium-release activated channels ( CRAC). Front Cell Neurosci 2014; 8:43. [PMID: 24605083 PMCID: PMC3932444 DOI: 10.3389/fncel.2014.00043] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Accepted: 01/29/2014] [Indexed: 11/13/2022] Open
Abstract
The spatial and temporal regulation of cellular calcium signals is modulated via two main Ca(2+) entry routes. Voltage-gated Ca(2+) channels (VGCC) and Ca(2+)-release activated channels (CRAC) enable Ca(2+) flow into electrically excitable and non-excitable cells, respectively. VGCC are well characterized transducers of electrical activity that allow Ca(2+) signaling into the cell in response to action potentials or subthreshold depolarizing stimuli. The identification of STromal Interaction Molecule (STIM) and Orai proteins has provided significant insights into the understanding of CRAC function and regulation. This review will summarize the current state of knowledge of STIM-Orai interaction and their contribution to cellular Ca(2+) handling mechanisms. We will then discuss the bidirectional actions of STIM1 on VGCC and CRAC. In contrast to the stimulatory role of STIM1 on Orai channel activity that facilitates Ca(2+) entry, recent reports indicated the ability of STIM1 to suppress VGCC activity. This new concept changes our traditional understanding of Ca(2+) handling mechanisms and highlights the existence of dynamically regulated signaling complexes of surface expressed ion channels and intracellular store membrane-embedded Ca(2+) sensors. Overall, STIM1 is emerging as a new class of regulatory proteins that fine-tunes Ca(2+) entry in response to endoplasmic/sarcoplasmic reticulum stress.
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Affiliation(s)
- Osama F Harraz
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, Libin Cardiovascular Institute, University of Calgary Calgary, AB, Canada ; Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University Alexandria, Egypt
| | - Christophe Altier
- Department of Physiology and Pharmacology, Snyder Institute for Chronic Diseases, Inflammation Research Network, University of Calgary Calgary, AB, Canada
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48
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Abstract
Plasma-membrane-localized Orai1 ion channel subunits interacting with ER-localized STIM1 molecules comprise the major subunit composition responsible for calcium release-activated calcium channels. STIM1 "translates" the Ca(2+) store content into Orai1 activity, making it a store-operated channel. Surprisingly, in addition to being the physical activator, STIM1 also modulates Orai1 properties, including its inactivation and permeation (see Chapter 1). STIM1 is thus more than a pure Orai1 activator. Within the past 7 years following the discovery of STIM and Orai proteins, the molecular mechanisms of STIM1/Orai1 activity and their functional importance have been studied in great detail. Much less is currently known about the other isoforms STIM2, Orai2, and Orai3. In this chapter, we summarize the current knowledge about STIM2, Orai2, and Orai3 properties and function. Are these homologues mainly modulators of predominantly STIM1/Orai1-mediated complexes or do store-dependent or -independent functions such as regulation of basal Ca(2+) concentration and activation of Orai3-containing complexes by arachidonic acid or by estrogen receptors point toward their "true" physiological function? Is Orai2 the Orai1 of neurons? A major focus of the review is on the functional relevance of STIM2, Orai2, and Orai3, some of which still remains speculative.
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Affiliation(s)
- Markus Hoth
- Department of Biophysics, Saarland University, Homburg, Germany
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49
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Scrimgeour NR, Wilson DP, Barritt GJ, Rychkov GY. Structural and stoichiometric determinants of Ca2+ release-activated Ca2+ ( CRAC) channel Ca2+-dependent inactivation. Biochim Biophys Acta 2014; 1838:1281-7. [PMID: 24472513 DOI: 10.1016/j.bbamem.2014.01.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Revised: 01/03/2014] [Accepted: 01/14/2014] [Indexed: 10/25/2022]
Abstract
Depletion of intracellular Ca(2+) stores in mammalian cells results in Ca(2+) entry across the plasma membrane mediated primarily by Ca(2+) release-activated Ca(2+) (CRAC) channels. Ca(2+) influx through these channels is required for the maintenance of homeostasis and Ca(2+) signaling in most cell types. One of the main features of native CRAC channels is fast Ca(2+)-dependent inactivation (FCDI), where Ca(2+) entering through the channel binds to a site near its intracellular mouth and causes a conformational change, closing the channel and limiting further Ca(2+) entry. Early studies suggested that FCDI of CRAC channels was mediated by calmodulin. However, since the discovery of STIM1 and Orai1 proteins as the basic molecular components of the CRAC channel, it has become apparent that FCDI is a more complex phenomenon. Data obtained using heterologous overexpression of STIM1 and Orai1 suggest that, in addition to calmodulin, several cytoplasmic domains of STIM1 and Orai1 and the selectivity filter within the channel pore are required for FCDI. The stoichiometry of STIM1 binding to Orai1 also has emerged as an important determinant of FCDI. Consequently, STIM1 protein expression levels have the potential to be an endogenous regulator of CRAC channel Ca(2+) influx. This review discusses the current understanding of the molecular mechanisms governing the FCDI of CRAC channels, including an evaluation of further experiments that may delineate whether STIM1 and/or Orai1 protein expression is endogenously regulated to modulate CRAC channel function, or may be dysregulated in some pathophysiological states.
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Affiliation(s)
- Nathan R Scrimgeour
- School of Medical Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - David P Wilson
- School of Medical Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Greg J Barritt
- Department of Medical Biochemistry, School of Medicine, Flinders University, Adelaide, South Australia 5001, Australia
| | - Grigori Y Rychkov
- School of Medical Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia.
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50
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Liang D, Zeng Q, Xu Z, Zhang H, Gui L, Xu C, Chen S, Zhang S, Huang S, Chen L. BAFF activates Erk1/2 promoting cell proliferation and survival by Ca2+-CaMKII-dependent inhibition of PP2A in normal and neoplastic B-lymphoid cells. Biochem Pharmacol 2013; 87:332-43. [PMID: 24269630 DOI: 10.1016/j.bcp.2013.11.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2013] [Revised: 11/12/2013] [Accepted: 11/13/2013] [Indexed: 01/25/2023]
Abstract
B-cell activating factor (BAFF) is involved in not only the physiology of normal B cells, but also the pathophysiology of aggressive B cells related to malignant and autoimmune diseases. However, how excessive BAFF promotes aggressive B-cell proliferation and survival is not well understood. Here we show that excessive human soluble BAFF (hsBAFF) enhanced cell proliferation and survival in normal and B-lymphoid (Raji) cells, which was associated with suppression of PP2A, resulting in activation of Erk1/2. This is supported by the findings that pretreatment with U0126 or PD98059, expression of dominant negative MKK1, or overexpression of PP2A prevented hsBAFF-induced activation of Erk1/2 and cell proliferation/viability in the cells. It appears that hsBAFF-mediated PP2A-Erk1/2 pathway and B-cell proliferation/viability was Ca(2+)-dependent, as pretreatment with BAPTA/AM, EGTA or 2-APB significantly attenuated these events. Furthermore, we found that inhibiting CaMKII with KN93 or silencing CaMKII also attenuated hsBAFF-mediated PP2A-Erk1/2 signaling and B-cell proliferation/viability. The results indicate that BAFF activates Erk1/2, in part through Ca(2+)-CaMKII-dependent inhibition of PP2A, increasing cell proliferation/viability in normal and neoplastic B-lymphoid cells. Our data suggest that inhibitors of CaMKII and Erk1/2, activator of PP2A or manipulation of intracellular Ca(2+) may be exploited for prevention of excessive BAFF-induced aggressive B-cell malignancies and autoimmune diseases.
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Affiliation(s)
- Dingfang Liang
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, PR China
| | - Qingyu Zeng
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, PR China
| | - Zhigang Xu
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, PR China
| | - Hai Zhang
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, PR China
| | - Lin Gui
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, PR China
| | - Chong Xu
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, PR China
| | - Sujuan Chen
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, PR China
| | - Shuangquan Zhang
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, PR China
| | - Shile Huang
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, LA 71130-3932, USA; Feist-Weiller Cancer Center, Louisiana State University Health Sciences Center, Shreveport, LA 71130-3932, USA.
| | - Long Chen
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, PR China.
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