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Parys JB, Lemos FO. The interplay between associated proteins, redox state and Ca 2+ in the intraluminal ER compartment regulates the IP 3 receptor. Cell Calcium 2024; 117:102823. [PMID: 37976974 DOI: 10.1016/j.ceca.2023.102823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 11/06/2023] [Accepted: 11/08/2023] [Indexed: 11/19/2023]
Abstract
There have been in the last three decades repeated publications indicating that the inositol 1,4,5-trisphosphate receptor (IP3R) is regulated not only by cytosolic Ca2+ but also by intraluminal Ca2+. Although most studies indicated that a decreasing intraluminal Ca2+ level led to an inhibition of the IP3R, a number of publications reported exactly the opposite effect, i.e. an inhibition of the IP3R by high intraluminal Ca2+ levels. Although intraluminal Ca2+-binding sites on the IP3Rs were reported, a regulatory role for them was not demonstrated. It is also well known that the IP3R is regulated by a vast array of associated proteins, but only relatively recently proteins were identified that can be linked to the regulation of the IP3R by intraluminal Ca2+. The first to be reported was annexin A1 that is proposed to associate with the second intraluminal loop of the IP3R at high intraluminal Ca2+ levels and to inhibit the IP3R. More recently, ERdj5/PDIA19 reductase was described to reduce an intraluminal disulfide bridge of IP3R1 only at low intraluminal Ca2+ levels and thereby to inhibit the IP3R. Annexin A1 and ERdj5/PDIA19 can therefore explain most of the experimental results on the regulation of the IP3R by intraluminal Ca2+. Further studies are needed to provide a fuller understanding of the regulation of the IP3R from the intraluminal side. These findings underscore the importance of the state of the endoplasmic reticulum in the control of IP3R activity.
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Affiliation(s)
- Jan B Parys
- KU Leuven, Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine, Leuven Kanker Instituut (LKI), Campus Gasthuisberg O&N1 - Box 802, Herestraat 49, B-3000, Leuven, Belgium.
| | - Fernanda O Lemos
- KU Leuven, Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine, Leuven Kanker Instituut (LKI), Campus Gasthuisberg O&N1 - Box 802, Herestraat 49, B-3000, Leuven, Belgium
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2
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Tambeaux A, Aguilar-Sánchez Y, Santiago DJ, Mascitti M, DiNovo KM, Mejía-Alvarez R, Fill M, Wayne Chen SR, Ramos-Franco J. Ligand sensitivity of type-1 inositol 1,4,5-trisphosphate receptor is enhanced by the D2594K mutation. Pflugers Arch 2023; 475:569-581. [PMID: 36881190 PMCID: PMC10105685 DOI: 10.1007/s00424-023-02796-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 02/06/2023] [Accepted: 02/12/2023] [Indexed: 03/08/2023]
Abstract
Inositol 1,4,5-trisphosphate receptor (IP3R) and ryanodine receptor (RyR) are homologous cation channels that mediate release of Ca2+ from the endoplasmic/sarcoplasmic reticulum (ER/SR) and thereby are involved in many physiological processes. In previous studies, we determined that when the D2594 residue, located at or near the gate of the IP3R type 1, was replaced by lysine (D2594K), a gain of function was obtained. This mutant phenotype was characterized by increased IP3 sensitivity. We hypothesized the IP3R1-D2594 determines the ligand sensitivity of the channel by electrostatically affecting the stability of the closed and open states. To test this possibility, the relationship between the D2594 site and IP3R1 regulation by IP3, cytosolic, and luminal Ca2+ was determined at the cellular, subcellular, and single-channel levels using fluorescence Ca2+ imaging and single-channel reconstitution. We found that in cells, D2594K mutation enhances the IP3 ligand sensitivity. Single-channel IP3R1 studies revealed that the conductance of IP3R1-WT and -D2594K channels is similar. However, IP3R1-D2594K channels exhibit higher IP3 sensitivity, with substantially greater efficacy. In addition, like its wild type (WT) counterpart, IP3R1-D2594K showed a bell-shape cytosolic Ca2+-dependency, but D2594K had greater activity at each tested cytosolic free Ca2+ concentration. The IP3R1-D2594K also had altered luminal Ca2+ sensitivity. Unlike IP3R1-WT, D2594K channel activity did not decrease at low luminal Ca2+ levels. Taken together, our functional studies indicate that the substitution of a negatively charged residue by a positive one at the channels' pore cytosolic exit affects the channel's gating behavior thereby explaining the enhanced ligand-channel's sensitivity.
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Affiliation(s)
- Allison Tambeaux
- Department of Physiology and Biophysics, Rush University Medical Center, Chicago, IL, USA
| | - Yuriana Aguilar-Sánchez
- Department of Physiology and Biophysics, Rush University Medical Center, Chicago, IL, USA.,Molecular Physiology & Biophysics, Baylor College of Medicine, Houston, TX, USA
| | - Demetrio J Santiago
- Department of Physiology and Biophysics, Rush University Medical Center, Chicago, IL, USA.,Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain
| | | | - Karyn M DiNovo
- Department of Physiology, Midwestern University, Downers Grove, IL, USA
| | | | - Michael Fill
- Department of Physiology and Biophysics, Rush University Medical Center, Chicago, IL, USA
| | - S R Wayne Chen
- Department of Physiology and Biophysics, Rush University Medical Center, Chicago, IL, USA.,Department of Physiology and Pharmacology, Libin Cardiovascular Institute, University of Calgary, Calgary, AB, Canada
| | - Josefina Ramos-Franco
- Department of Physiology and Biophysics, Rush University Medical Center, Chicago, IL, USA.
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3
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Buckley C, Wilson C, McCarron JG. FK506 regulates Ca 2+ release evoked by inositol 1,4,5-trisphosphate independently of FK-binding protein in endothelial cells. Br J Pharmacol 2020; 177:1131-1149. [PMID: 31705533 PMCID: PMC7042112 DOI: 10.1111/bph.14905] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 10/08/2019] [Accepted: 10/10/2019] [Indexed: 12/16/2022] Open
Abstract
Background and Purpose FK506 and rapamycin are modulators of FK‐binding proteins (FKBP) that are used to suppress immune function after organ and hematopoietic stem cell transplantations. The drugs share the unwanted side‐effect of evoking hypertension that is associated with reduced endothelial function and nitric oxide production. The underlying mechanisms are not understood. FKBP may regulate IP3 receptors (IP3R) and ryanodine receptors (RyR) to alter Ca2+ signalling in endothelial cells. Experimental Approach We investigated the effects of FK506 and rapamycin on Ca2+ release via IP3R and RyR in hundreds of endothelial cells, using the indicator Cal‐520, in intact mesenteric arteries from male Sprague‐Dawley rats. IP3Rs were activated by acetylcholine or localised photo‐uncaging of IP3, and RyR by caffeine. Key Results While FKBPs were present, FKBP modulation with rapamycin did not alter IP3‐evoked Ca2+ release. Conversely, FK506, which modulates FKBP and blocks calcineurin, increased IP3‐evoked Ca2+ release. Inhibition of calcineurin (okadiac acid or cypermethrin) also increased IP3‐evoked Ca2+ release and blocked FK506 effects. When calcineurin was inhibited, FK506 reduced IP3‐evoked Ca2+ release. These findings suggest that IP3‐evoked Ca2+ release is not modulated by FKBP, but by FK506‐mediated calcineurin inhibition. The RyR modulators caffeine and ryanodine failed to alter Ca2+ signalling suggesting that RyR is not functional in native endothelium. Conclusion and Implications The hypertensive effects of the immunosuppressant drugs FK506 and rapamycin, while mediated by endothelial cells, do not appear to be exerted at the documented cellular targets of Ca2+ release and altered FKBP binding to IP3 and RyR.
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Affiliation(s)
- Charlotte Buckley
- Strathclyde Institute of Pharmacy and Biomedical Science, University of Strathclyde, Glasgow, UK
| | - Calum Wilson
- Strathclyde Institute of Pharmacy and Biomedical Science, University of Strathclyde, Glasgow, UK
| | - John G McCarron
- Strathclyde Institute of Pharmacy and Biomedical Science, University of Strathclyde, Glasgow, UK
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Non-canonical function of IRE1α determines mitochondria-associated endoplasmic reticulum composition to control calcium transfer and bioenergetics. Nat Cell Biol 2019; 21:755-767. [PMID: 31110288 DOI: 10.1038/s41556-019-0329-y] [Citation(s) in RCA: 161] [Impact Index Per Article: 32.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Accepted: 04/09/2019] [Indexed: 12/14/2022]
Abstract
Mitochondria-associated membranes (MAMs) are central microdomains that fine-tune bioenergetics by the local transfer of calcium from the endoplasmic reticulum to the mitochondrial matrix. Here, we report an unexpected function of the endoplasmic reticulum stress transducer IRE1α as a structural determinant of MAMs that controls mitochondrial calcium uptake. IRE1α deficiency resulted in marked alterations in mitochondrial physiology and energy metabolism under resting conditions. IRE1α determined the distribution of inositol-1,4,5-trisphosphate receptors at MAMs by operating as a scaffold. Using mutagenesis analysis, we separated the housekeeping activity of IRE1α at MAMs from its canonical role in the unfolded protein response. These observations were validated in vivo in the liver of IRE1α conditional knockout mice, revealing broad implications for cellular metabolism. Our results support an alternative function of IRE1α in orchestrating the communication between the endoplasmic reticulum and mitochondria to sustain bioenergetics.
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Pecze L, Schwaller B. Characterization and modeling of Ca2+ oscillations in mouse primary mesothelial cells. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1853:632-45. [DOI: 10.1016/j.bbamcr.2014.12.025] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Revised: 12/16/2014] [Accepted: 12/19/2014] [Indexed: 10/24/2022]
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Gordienko D, Povstyan O, Sukhanova K, Raphaël M, Harhun M, Dyskina Y, Lehen'kyi V, Jama A, Lu ZL, Skryma R, Prevarskaya N. Impaired P2X signalling pathways in renal microvascular myocytes in genetic hypertension. Cardiovasc Res 2014; 105:131-42. [PMID: 25514930 DOI: 10.1093/cvr/cvu249] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
AIMS P2X receptors (P2XRs) mediate sympathetic control and autoregulation of renal circulation triggering preglomerular vasoconstriction, which protects glomeruli from elevated pressures. Although previous studies established a casual link between glomerular susceptibility to hypertensive injury and decreased preglomerular vascular reactivity to P2XR activation, the mechanisms of attenuation of the P2XR signalling in hypertension remained unknown. We aimed to analyse molecular mechanisms of the impairment of P2XR signalling in renal vascular smooth muscle cells (RVSMCs) in genetic hypertension. METHODS AND RESULTS We compared the expression of pertinent genes and P2XR-linked Ca(2+) entry and Ca(2+) release mechanisms in RVSMCs of spontaneously hypertensive rats (SHRs) and their normotensive controls, Wistar Kyoto (WKY) rats. We found that, in SHR RVSMCs, P2XR-linked Ca(2+) entry and Ca(2+) release from the sarcoplasmic reticulum (SR) are both significantly reduced. The former is due to down-regulation of the P2X1 subunit. The latter is caused by a decrease of the SR Ca(2+) load. The SR Ca(2+) load reduction is caused by attenuated Ca(2+) uptake via down-regulated sarco-/endoplasmic reticulum Ca(2+)-ATPase 2b and elevated Ca(2+) leak from the SR via ryanodine receptors (RyRs) and inositol 1,4,5-trisphosphate receptors. Spontaneous activity of these Ca(2+)-release channels is augmented due to up-regulation of RyR type 2 and elevated IP3 production by up-regulated phospholipase C-β1. CONCLUSIONS Our study unravels the cellular and molecular mechanisms of attenuation of P2XR-mediated preglomerular vasoconstriction that elevates glomerular susceptibility to harmful hypertensive pressures. This provides an important impetus towards understanding of the pathology of hypertensive renal injury.
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Affiliation(s)
- Dmitri Gordienko
- INSERM U1003, Laboratory of Excellence, Ion Channels Science and Therapeutics, Université des Sciences et Technologies de Lille, Batiment SN3, Villeneuve d'Ascq 59655, France Laboratory of Molecular Pharmacology and Biophysics of Cell Signaling, Bogomoletz Institute of Physiology, Kiev, Ukraine
| | - Oleksandr Povstyan
- Laboratory of Molecular Pharmacology and Biophysics of Cell Signaling, Bogomoletz Institute of Physiology, Kiev, Ukraine Division of Basic Medical Sciences, St. George's, University of London, London, UK
| | - Khrystyna Sukhanova
- Laboratory of Molecular Pharmacology and Biophysics of Cell Signaling, Bogomoletz Institute of Physiology, Kiev, Ukraine
| | - Maylis Raphaël
- INSERM U1003, Laboratory of Excellence, Ion Channels Science and Therapeutics, Université des Sciences et Technologies de Lille, Batiment SN3, Villeneuve d'Ascq 59655, France
| | - Maksym Harhun
- Laboratory of Molecular Pharmacology and Biophysics of Cell Signaling, Bogomoletz Institute of Physiology, Kiev, Ukraine Division of Basic Medical Sciences, St. George's, University of London, London, UK
| | - Yulia Dyskina
- Laboratory of Molecular Pharmacology and Biophysics of Cell Signaling, Bogomoletz Institute of Physiology, Kiev, Ukraine
| | - V'yacheslav Lehen'kyi
- INSERM U1003, Laboratory of Excellence, Ion Channels Science and Therapeutics, Université des Sciences et Technologies de Lille, Batiment SN3, Villeneuve d'Ascq 59655, France
| | - Abdirahman Jama
- MRC, Centre for Reproductive Health, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, UK
| | - Zhi-Liang Lu
- MRC, Centre for Reproductive Health, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, UK Department of Biological Sciences, Xi'an Jiaotong-Liverpool University, Suzhou, China
| | - Roman Skryma
- INSERM U1003, Laboratory of Excellence, Ion Channels Science and Therapeutics, Université des Sciences et Technologies de Lille, Batiment SN3, Villeneuve d'Ascq 59655, France
| | - Natalia Prevarskaya
- INSERM U1003, Laboratory of Excellence, Ion Channels Science and Therapeutics, Université des Sciences et Technologies de Lille, Batiment SN3, Villeneuve d'Ascq 59655, France
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7
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FK506 binding proteins: Cellular regulators of intracellular Ca2+ signalling. Eur J Pharmacol 2013; 700:181-93. [DOI: 10.1016/j.ejphar.2012.12.029] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Revised: 12/04/2012] [Accepted: 12/18/2012] [Indexed: 02/04/2023]
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Vais H, Foskett JK, Ullah G, Pearson JE, Mak DOD. Permeant calcium ion feed-through regulation of single inositol 1,4,5-trisphosphate receptor channel gating. ACTA ACUST UNITED AC 2012; 140:697-716. [PMID: 23148262 PMCID: PMC3514735 DOI: 10.1085/jgp.201210804] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The ubiquitous inositol 1,4,5-trisphosphate (InsP(3)) receptor (InsP(3)R) Ca(2+) release channel plays a central role in the generation and modulation of intracellular Ca(2+) signals, and is intricately regulated by multiple mechanisms including cytoplasmic ligand (InsP(3), free Ca(2+), free ATP(4-)) binding, posttranslational modifications, and interactions with cytoplasmic and endoplasmic reticulum (ER) luminal proteins. However, regulation of InsP(3)R channel activity by free Ca(2+) in the ER lumen ([Ca(2+)](ER)) remains poorly understood because of limitations of Ca(2+) flux measurements and imaging techniques. Here, we used nuclear patch-clamp experiments in excised luminal-side-out configuration with perfusion solution exchange to study the effects of [Ca(2+)](ER) on homotetrameric rat type 3 InsP(3)R channel activity. In optimal [Ca(2+)](i) and subsaturating [InsP(3)], jumps of [Ca(2+)](ER) from 70 nM to 300 µM reduced channel activity significantly. This inhibition was abrogated by saturating InsP(3) but restored when [Ca(2+)](ER) was raised to 1.1 mM. In suboptimal [Ca(2+)](i), jumps of [Ca(2+)](ER) (70 nM to 300 µM) enhanced channel activity. Thus, [Ca(2+)](ER) effects on channel activity exhibited a biphasic dependence on [Ca(2+)](i). In addition, the effect of high [Ca(2+)](ER) was attenuated when a voltage was applied to oppose Ca(2+) flux through the channel. These observations can be accounted for by Ca(2+) flux driven through the open InsP(3)R channel by [Ca(2+)](ER), raising local [Ca(2+)](i) around the channel to regulate its activity through its cytoplasmic regulatory Ca(2+)-binding sites. Importantly, [Ca(2+)](ER) regulation of InsP(3)R channel activity depended on cytoplasmic Ca(2+)-buffering conditions: it was more pronounced when [Ca(2+)](i) was weakly buffered but completely abolished in strong Ca(2+)-buffering conditions. With strong cytoplasmic buffering and Ca(2+) flux sufficiently reduced by applied voltage, both activation and inhibition of InsP(3)R channel gating by physiological levels of [Ca(2+)](ER) were completely abolished. Collectively, these results rule out Ca(2+) regulation of channel activity by direct binding to the luminal aspect of the channel.
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Affiliation(s)
- Horia Vais
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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9
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Abstract
Intercellular calcium (Ca(2+)) waves (ICWs) represent the propagation of increases in intracellular Ca(2+) through a syncytium of cells and appear to be a fundamental mechanism for coordinating multicellular responses. ICWs occur in a wide diversity of cells and have been extensively studied in vitro. More recent studies focus on ICWs in vivo. ICWs are triggered by a variety of stimuli and involve the release of Ca(2+) from internal stores. The propagation of ICWs predominately involves cell communication with internal messengers moving via gap junctions or extracellular messengers mediating paracrine signaling. ICWs appear to be important in both normal physiology as well as pathophysiological processes in a variety of organs and tissues including brain, liver, retina, cochlea, and vascular tissue. We review here the mechanisms of initiation and propagation of ICWs, the key intra- and extracellular messengers (inositol 1,4,5-trisphosphate and ATP) mediating ICWs, and the proposed physiological functions of ICWs.
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Affiliation(s)
- Luc Leybaert
- Department of Basic Medical Sciences, Physiology Group, Faculty of Medicine & Health Sciences, Ghent University, Ghent, Belgium.
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10
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Abstract
The Ca(2) (+) signals evoked by inositol 1,4,5-trisphosphate (IP(3)) are built from elementary Ca(2) (+) release events involving progressive recruitment of IP(3) receptors (IP(3)R), intracellular Ca(2) (+) channels that are expressed in almost all animal cells. The smallest events ('blips') result from opening of single IP(3)R. Larger events ('puffs') reflect the near-synchronous opening of a small cluster of IP(3)R. These puffs become more frequent as the stimulus intensity increases and they eventually trigger regenerative Ca(2) (+) waves that propagate across the cell. This hierarchical recruitment of IP(3)R is important in allowing Ca(2) (+) signals to be delivered locally to specific target proteins or more globally to the entire cell. Co-regulation of IP(3)R by Ca(2) (+) and IP(3), the ability of a single IP(3)R rapidly to mediate a large efflux of Ca(2) (+) from the endoplasmic reticulum, and the assembly of IP(3)R into clusters are key features that allow IP(3)R to propagate Ca(2) (+) signals regeneratively. We review these properties of IP(3)R and the structural basis of IP(3)R behavior.
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Affiliation(s)
- Colin W Taylor
- Department of Pharmacology, Tennis Court Road, CB2 1PD, Cambridge, UK,
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11
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ERp44 C160S/C212S mutants regulate IP3R1 channel activity. Protein Cell 2011; 2:990-6. [PMID: 22183808 DOI: 10.1007/s13238-011-1116-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Accepted: 10/20/2011] [Indexed: 10/14/2022] Open
Abstract
Previous studies have indicated that ERp44 inhibits inositol 1,4,5-trisphosphate (IP(3))-induced Ca(2+) release (IICR) via IP(3)R(1), but the mechanism remains largely unexplored. Using extracellular ATP to induce intracellular calcium transient as an IICR model, Ca(2+) image, pull down assay, and Western blotting experiments were carried out in the present study. We found that extracellular ATP induced calcium transient via IP(3)Rs (IICR) and the IICR were markedly decreased in ERp44 overexpressed Hela cells. The inhibitory effect of C160S/C212S but not C29S/T396A/ΔT(331-377) mutants of ERp44 on IICR were significantly decreased compared with ERp44. However, the binding capacity of ERp44 to L3V domain of IP(3)R(1) (1L3V) was enhanced by ERp44 C160S/C212S mutation. Taken together, these results suggest that the mutants of ERp44, C160/C212, can more tightly bind to IP(3)R(1) but exhibit a weak inhibition of IP(3)R(1) channel activity in Hela cells.
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12
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Hagenston AM, Bading H. Calcium signaling in synapse-to-nucleus communication. Cold Spring Harb Perspect Biol 2011; 3:a004564. [PMID: 21791697 DOI: 10.1101/cshperspect.a004564] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Changes in the intracellular concentration of calcium ions in neurons are involved in neurite growth, development, and remodeling, regulation of neuronal excitability, increases and decreases in the strength of synaptic connections, and the activation of survival and programmed cell death pathways. An important aspect of the signals that trigger these processes is that they are frequently initiated in the form of glutamatergic neurotransmission within dendritic trees, while their completion involves specific changes in the patterns of genes expressed within neuronal nuclei. Accordingly, two prominent aims of research concerned with calcium signaling in neurons are determination of the mechanisms governing information conveyance between synapse and nucleus, and discovery of the rules dictating translation of specific patterns of inputs into appropriate and specific transcriptional responses. In this article, we present an overview of the avenues by which glutamatergic excitation of dendrites may be communicated to the neuronal nucleus and the primary calcium-dependent signaling pathways by which synaptic activity can invoke changes in neuronal gene expression programs.
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Affiliation(s)
- Anna M Hagenston
- CellNetworks-Cluster of Excellence, Department of Neurobiology, Interdisciplinary Center for Neurosciences, University of Heidelberg, 69120 Heidelberg, Germany
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13
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Taylor CW, Rahman T, Tovey SC, Dedos SG, Taylor EJA, Velamakanni S. IP3 receptors: some lessons from DT40 cells. Immunol Rev 2009; 231:23-44. [PMID: 19754888 DOI: 10.1111/j.1600-065x.2009.00807.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Inositol-1,4,5-trisphosphate receptors (IP3Rs) are intracellular Ca2+ channels that are regulated by IP3 and Ca2+ and are modulated by many additional signals. These properties allow them to initiate and, via Ca2+-induced Ca2+ release, regeneratively propagate Ca2+ signals evoked by receptors that stimulate formation of IP3. The ubiquitous expression of IP3R highlights their importance, but it also presents problems when attempting to resolve the behavior of defined IP3R. DT40 cells are a pre-B-lymphocyte cell line in which high rates of homologous recombination afford unrivalled opportunities to disrupt endogenous genes. DT40-knockout cells with both alleles of each of the three IP3R genes disrupted provide the only null-background for analysis of homogenous recombinant IP3R. We review the properties of DT40 cells and consider three areas where they have contributed to understanding IP3R behavior. Patch-clamp recording from the nuclear envelope and Ca2+ release from intracellular stores loaded with a low-affinity Ca2+ indicator address the mechanisms leading to activation of IP(3)R. We show that IP3 causes intracellular IP3R to cluster and re-tune their responses to IP3 and Ca2+, better equipping them to mediate regenerative Ca2+ signals. Finally, we show that DT40 cells reliably count very few IP3R into the plasma membrane, where they mediate about half the Ca2+ entry evoked by the B-cell antigen receptor.
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Affiliation(s)
- Colin W Taylor
- Department of Pharmacology, University of Cambridge, Cambridge, UK.
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14
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Vangheluwe P, Sepúlveda MR, Missiaen L, Raeymaekers L, Wuytack F, Vanoevelen J. Intracellular Ca2+- and Mn2+-Transport ATPases. Chem Rev 2009; 109:4733-59. [DOI: 10.1021/cr900013m] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Peter Vangheluwe
- Laboratory of Ca2+-transport ATPases and Laboratory of Molecular and Cellular Signaling, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - M. Rosario Sepúlveda
- Laboratory of Ca2+-transport ATPases and Laboratory of Molecular and Cellular Signaling, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Ludwig Missiaen
- Laboratory of Ca2+-transport ATPases and Laboratory of Molecular and Cellular Signaling, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Luc Raeymaekers
- Laboratory of Ca2+-transport ATPases and Laboratory of Molecular and Cellular Signaling, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Frank Wuytack
- Laboratory of Ca2+-transport ATPases and Laboratory of Molecular and Cellular Signaling, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Jo Vanoevelen
- Laboratory of Ca2+-transport ATPases and Laboratory of Molecular and Cellular Signaling, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Leuven, Belgium
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15
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Kang S, Kang J, Kwon H, Frueh D, Yoo SH, Wagner G, Park S. Effects of Redox Potential and Ca2+ on the Inositol 1,4,5-Trisphosphate Receptor L3-1 Loop Region. J Biol Chem 2008; 283:25567-25575. [DOI: 10.1074/jbc.m803321200] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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16
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Spät A, Szanda G, Csordás G, Hajnóczky G. High- and low-calcium-dependent mechanisms of mitochondrial calcium signalling. Cell Calcium 2008; 44:51-63. [PMID: 18242694 DOI: 10.1016/j.ceca.2007.11.015] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2007] [Revised: 11/23/2007] [Accepted: 11/30/2007] [Indexed: 11/30/2022]
Abstract
The Ca(2+) coupling between endoplasmic reticulum (ER) and mitochondria is central to multiple cell survival and cell death mechanisms. Cytoplasmic [Ca(2+)] ([Ca(2+)](c)) spikes and oscillations produced by ER Ca(2+) release are effectively delivered to the mitochondria. Propagation of [Ca(2+)](c) signals to the mitochondria requires the passage of Ca(2+) across three membranes, namely the ER membrane, the outer mitochondrial membrane (OMM) and the inner mitochondrial membrane (IMM). Strategic positioning of the mitochondria by cytoskeletal transport and interorganellar tethers provides a means to promote the local transfer of Ca(2+) between the ER membrane and OMM. In this setting, even >100 microM [Ca(2+)] may be attained to activate the low affinity mitochondrial Ca(2+) uptake. However, a mitochondrial [Ca(2+)] rise has also been documented during submicromolar [Ca(2+)](c) elevations. Evidence has been emerging that Ca(2+) exerts allosteric control on the Ca(2+) transport sites at each membrane, providing mechanisms that may facilitate the Ca(2+) delivery to the mitochondria. Here we discuss the fundamental mechanisms of ER and mitochondrial Ca(2+) transport, particularly the control of their activity by Ca(2+) and evaluate both high- and low-[Ca(2+)]-activated mitochondrial calcium signals in the context of cell physiology.
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Affiliation(s)
- András Spät
- Department of Physiology, Faculty of Medicine, Semmelweis University, Budapest, Hungary.
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17
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McCarron JG, Chalmers S, Muir TC. `Quantal' Ca2+ release at the cytoplasmic aspect of the Ins(1,4,5)P3R channel in smooth muscle. J Cell Sci 2008; 121:86-98. [DOI: 10.1242/jcs.017541] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Smooth muscle responds to activation of the inositol (1,4,5)-trisphosphate receptor [Ins(1,4,5)P3R] with a graded concentration-dependent (`quantal') Ca2+ release from the sarcoplasmic reticulum (SR) store. Graded release seems incompatible both with the finite capacity of the store and the Ca2+-induced Ca2+ release (CICR)-like facility, at Ins(1,4,5)P3Rs, that, once activated, should release the entire content of SR Ca2+. The structural organization of the SR and the regulation of Ins(1,4,5)P3R activity by inositol (1,4,5)-trisphosphate [Ins(1,4,5)P3] and Ca2+ have each been proposed to explain `quantal' Ca2+ release. Here, we propose that regulation of Ins(1,4,5)P3R activity by lumenal Ca2+ acting at the cytoplasmic aspect of the receptor might explain `quantal' Ca2+ release in smooth muscle. The entire SR store was found to be lumenally continuous and Ca2+ could diffuse freely throughout: peculiarities of SR structure are unlikely to account for `quantal' release. While Ca2+ release was regulated by [Ca2+] within the SR, the velocity of release increased (accelerated) during the release process. The extent of acceleration of release determined the peak cytoplasmic [Ca2+] and was attenuated by a reduction in SR [Ca2+] or an increase in cytoplasmic Ca2+ buffering. Positive feedback by released Ca2+ acting at the cytoplasmic aspect of Ins(1,4,5)P3Rs (i.e. CICR-like) might (a) account for the acceleration, (b) provide the regulation of release by SR [Ca2+] and (c) explain the `quantal' release process itself. During Ca2+ release, SR [Ca2+] and thus unitary Ins(1,4,5)P3R currents decline, CICR reduces and stops. With increasing [Ins(1,4,5)P3], coincidental activation of several neighbouring Ins(1,4,5)P3Rs offsets the reduced Ins(1,4,5)P3R current to renew CICR and Ca2+ release.
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Affiliation(s)
- John G. McCarron
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, John Arbuthnott Building, 27 Taylor Street, Glasgow G4 0NR, UK
| | - Susan Chalmers
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, John Arbuthnott Building, 27 Taylor Street, Glasgow G4 0NR, UK
| | - Thomas C. Muir
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, John Arbuthnott Building, 27 Taylor Street, Glasgow G4 0NR, UK
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18
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Abstract
The inositol 1,4,5-trisphosphate (InsP3) receptors (InsP3Rs) are a family of Ca2+ release channels localized predominately in the endoplasmic reticulum of all cell types. They function to release Ca2+ into the cytoplasm in response to InsP3 produced by diverse stimuli, generating complex local and global Ca2+ signals that regulate numerous cell physiological processes ranging from gene transcription to secretion to learning and memory. The InsP3R is a calcium-selective cation channel whose gating is regulated not only by InsP3, but by other ligands as well, in particular cytoplasmic Ca2+. Over the last decade, detailed quantitative studies of InsP3R channel function and its regulation by ligands and interacting proteins have provided new insights into a remarkable richness of channel regulation and of the structural aspects that underlie signal transduction and permeation. Here, we focus on these developments and review and synthesize the literature regarding the structure and single-channel properties of the InsP3R.
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Affiliation(s)
- J Kevin Foskett
- Department of Physiology, University of Pennsylvania, Philadelphia 19104-6085, USA.
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19
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Yamashita M. ‘Quantal’ Ca2+release reassessed - a clue to oscillation and synchronization. FEBS Lett 2006; 580:4979-83. [PMID: 16938295 DOI: 10.1016/j.febslet.2006.08.023] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2006] [Accepted: 08/14/2006] [Indexed: 11/26/2022]
Abstract
Ca(2+) release from intracellular Ca(2+) stores, a pivotal event in Ca(2+) signaling, is a 'quantal' process; it terminates after a rapid release of a fraction of stored Ca(2+). To explain the 'quantal' nature, 'all-or-none' model and 'steady-state' model were proposed. This article shortly reviews these hypotheses and considers a recently proposed mechanism, 'luminal potential' model, in which the membrane potential of Ca(2+) store regulates Ca(2+) efflux. By reassessing the 'quantal' nature, other important features of Ca(2+) signaling, oscillation and synchronization, are highlighted. The mechanism for 'quantal' Ca(2+) release may underlie the temporal and spatial control of Ca(2+) signaling.
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Affiliation(s)
- Masayuki Yamashita
- Department of Physiology I, Nara Medical University, Shijo-cho 840, Kashihara 634-8521, Japan.
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20
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Yamashita M, Sugioka M, Ogawa Y. Voltage- and Ca2+-activated potassium channels in Ca2+ store control Ca2+ release. FEBS J 2006; 273:3585-97. [PMID: 16884498 DOI: 10.1111/j.1742-4658.2006.05365.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ca2+ release from Ca2+ stores is a 'quantal' process; it terminates after a rapid release of stored Ca2+. To explain the quantal nature, it has been supposed that a decrease in luminal Ca2+ acts as a 'brake' on store release. However, the mechanism for the attenuation of Ca2+ efflux remains unknown. We show that Ca2+ release is controlled by voltage- and Ca2+-activated potassium channels in the Ca2+ store. The potassium channel was identified as the big or maxi-K (BK)-type, and was activated by positive shifts in luminal potential and luminal Ca2+ increases, as revealed by patch-clamp recordings from an exposed nuclear envelope. The blockage or closure of the store BK channel due to Ca2+ efflux developed lumen-negative potentials, as revealed with an organelle-specific voltage-sensitive dye [DiOC5(3); 3,3'-dipentyloxacarbocyanine iodide], and suppressed Ca2+ release. The store BK channels are reactivated by Ca2+ uptake by Ca2+ pumps regeneratively with K+ entry to allow repetitive Ca2+ release. Indeed, the luminal potential oscillated bistably by approximately 45 mV in amplitude. Our study suggests that Ca2+ efflux-induced store BK channel closures attenuate Ca2+ release with decreases in counter-influx of K+.
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21
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MacMillan D, Currie S, Bradley KN, Muir TC, McCarron JG. In smooth muscle, FK506-binding protein modulates IP3 receptor-evoked Ca2+ release by mTOR and calcineurin. J Cell Sci 2005; 118:5443-51. [PMID: 16278292 DOI: 10.1242/jcs.02657] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Ca2+ release from the sarcoplasmic reticulum (SR) by the IP3 receptors (IP3Rs) crucially regulates diverse cell signalling processes from reproduction to apoptosis. Release from the IP3R may be modulated by endogenous proteins associated with the receptor, such as the 12 kDa FK506-binding protein (FKBP12), either directly or indirectly by inhibition of the phosphatase calcineurin. Here, we report that, in addition to calcineurin, FKPBs modulate release through the mammalian target of rapamycin (mTOR), a kinase that potentiates Ca2+ release from the IP3R in smooth muscle. The presence of FKBP12 was confirmed in colonic myocytes and co-immunoprecipitated with the IP3R. In aortic smooth muscle, however, although present, FKBP12 did not co-immunoprecipitate with IP3R. In voltage-clamped single colonic myocytes rapamycin, which together with FKBP12 inhibits mTOR (but not calcineurin), decreased the rise in cytosolic Ca2+ concentration ([Ca2+]c) evoked by IP3R activation (by photolysis of caged IP3), without decreasing the SR luminal Ca2+ concentration ([Ca2+]l) as did the mTOR inhibitors RAD001 and LY294002. However, FK506, which with FKBP12 inhibits calcineurin (but not mTOR), potentiated the IP3-evoked [Ca2+]c increase. This potentiation was due to the inhibition of calcineurin; it was mimicked by the phosphatase inhibitors cypermethrin and okadaic acid. The latter two inhibitors also prevented the FK506-evoked increase as did a calcineurin inhibitory peptide (CiP). In aortic smooth muscle, where FKBP12 was not associated with IP3R, the IP3-mediated Ca2+ release was unaffected by FK506 or rapamycin. Together, these results suggest that FKBP12 has little direct effect on IP3-mediated Ca2+ release, even though it is associated with IP3R in colonic myocytes. However, FKBP12 might indirectly modulate Ca2+ release through two effector proteins: (1) mTOR, which potentiates and (2) calcineurin, which inhibits Ca2+ release from IP3R in smooth muscle.
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Affiliation(s)
- Debbi MacMillan
- Institute of Biomedical and Life Sciences, Neuroscience and Biomedical Systems, West Medical Building, University of Glasgow, Glasgow, G12 8QQ, UK
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22
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Koulen P, Duncan RS, Liu J, Cohen NE, Yannazzo JAS, McClung N, Lockhart CL, Branden M, Buechner M. Polycystin-2 accelerates Ca2+ release from intracellular stores in Caenorhabditis elegans. Cell Calcium 2005; 37:593-601. [PMID: 15862350 DOI: 10.1016/j.ceca.2005.03.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2004] [Revised: 03/07/2005] [Accepted: 03/10/2005] [Indexed: 11/15/2022]
Abstract
Polycystin-2, a member of the TRP family of calcium channels, is encoded by the human PKD2 gene. Mutations in that gene can lead to swelling of nephrons into the fluid-filled cysts of polycystic kidney disease. In addition to expression in tubular epithelial cells, human polycystin-2 is found in muscle and neuronal cells, but its cell biological function has been unclear. A homologue in Caenorhabditis elegans is necessary for male mating behavior. We compared the behavior, calcium signaling mechanisms, and electrophysiology of wild-type and pkd-2 knockout C. elegans. In addition to characterizing PKD-2-mediated aggregation and mating behaviors, we found that polycystin-2 is an intracellular Ca(2+) release channel that is required for the normal pattern of Ca(2+) responses involving IP(3) and ryanodine receptor-mediated Ca(2+) release from intracellular stores. Activity of polycystin-2 creates brief cytosolic Ca(2+) transients with increased amplitude and decreased duration. Polycystin-2, along with the IP(3) and ryanodine receptors, acts as a major calcium-release channel in the endoplasmic reticulum in cells where rapid calcium signaling is required, and polycystin-2 activity is essential in those excitable cells for rapid responses to stimuli.
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Affiliation(s)
- Peter Koulen
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center at Fort Worth, 76107-2699, USA.
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23
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Abstract
A large amount of data and observations on inositol 1,4,5-trisphosphate (IP(3)) binding to the IP(3) receptor/Ca(2+) channel, the steady-state activity of the channel, and its inactivation by IP(3) can be explained by assuming one activation and one inhibition module, both allosterically operated by Ca(2+), IP(3), and ATP, and one adaptation element, driven by IP(3), Ca(2+), and the interconversion between two possible conformations of the receptor. The adaptation module becomes completely insensitive to a second IP(3) pulse within 80 s. Observed kinetic responses are well reproduced if, in addition, two module open states are rendered inactive by the current charge carrier Mn(2+). The inactivation time constants are 59 s in the activation, and 0.75 s in the adaptation module. The in vivo open probability of the channel is predicted to be almost in coincidence with the behavior in lipid bilayers for IP(3) levels of 0.2 and 2 microM and one-order-higher at 0.02 microM IP(3), whereas at 180 microM IP(3) the maximal in vivo activity may be 2.5-orders higher than in bilayers and restricted to a narrower Ca(2+) domain (approximately 10 microM-wide versus approximately 100 microM-wide). IP(3) is likely to inhibit channel activity at < or =120 nM Ca(2+) in vivo.
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Affiliation(s)
- Irina Baran
- Biophysics Department, Faculty of Medicine, University of Medicine and Pharmacy Carol Davila, Bucharest, Romania.
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24
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Verkhratsky A. Physiology and Pathophysiology of the Calcium Store in the Endoplasmic Reticulum of Neurons. Physiol Rev 2005; 85:201-79. [PMID: 15618481 DOI: 10.1152/physrev.00004.2004] [Citation(s) in RCA: 560] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The endoplasmic reticulum (ER) is the largest single intracellular organelle, which is present in all types of nerve cells. The ER is an interconnected, internally continuous system of tubules and cisterns, which extends from the nuclear envelope to axons and presynaptic terminals, as well as to dendrites and dendritic spines. Ca2+release channels and Ca2+pumps residing in the ER membrane provide for its excitability. Regulated ER Ca2+release controls many neuronal functions, from plasmalemmal excitability to synaptic plasticity. Enzymatic cascades dependent on the Ca2+concentration in the ER lumen integrate rapid Ca2+signaling with long-lasting adaptive responses through modifications in protein synthesis and processing. Disruptions of ER Ca2+homeostasis are critically involved in various forms of neuropathology.
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Affiliation(s)
- Alexei Verkhratsky
- The University of Manchester, Faculty of Biological Sciences, United Kingdom.
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25
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Fraiman D, Dawson SP. A model of IP3 receptor with a luminal calcium binding site: stochastic simulations and analysis. Cell Calcium 2004; 35:403-13. [PMID: 15003850 DOI: 10.1016/j.ceca.2003.10.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2003] [Revised: 08/20/2003] [Accepted: 10/16/2003] [Indexed: 11/26/2022]
Abstract
We have constructed a stochastic model of the inositol 1,4,5-trisphosphate receptor-Ca2+ channel that is based on quantitative measurements of the channel's properties. It displays the observed dependence of the open probability of the channel with cytosolic [Ca2+] and [IP3] and gives values for the dwell times that agree with the observations. The model includes an explicit dependence of channel gating with luminal calcium. This not only explains several observations reported in the literature, but also provides a possible explanation of why the open probabilities and shapes of the bell-shaped curves reported in [Nature 351 (1991) 751] and in [Proc. Natl. Acad. Sci. U.S.A. 269 (1998) 7238] are so different.
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Affiliation(s)
- Daniel Fraiman
- Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón I (1428), Buenos Aires, Argentina.
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26
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Carbajal V, Vargas MH, Flores-Soto E, Martínez-Cordero E, Bazán-Perkins B, Montaño LM. LTD4 induces hyperresponsiveness to histamine in bovine airway smooth muscle: role of SR-ATPase Ca2+ pump and tyrosine kinase. Am J Physiol Lung Cell Mol Physiol 2004; 288:L84-92. [PMID: 15377496 DOI: 10.1152/ajplung.00446.2003] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Airway hyperresponsiveness is a key feature of asthma, but its mechanisms remain poorly understood. Leukotriene D(4) (LTD(4)) is one of the few molecules capable of producing airway hyperresponsiveness. In this study, LTD(4), but not leukotriene C(4) (LTC(4)), produced a leftward displacement of the concentration-response curve to histamine in bovine airway smooth muscle strips. Neither LTC(4) nor LTD(4) modified the concentration-response curve to carbachol. In simultaneous measurements of intracellular Ca(2+) ([Ca(2+)](i)) and contraction, histamine or carbachol produced a transient Ca(2+) peak followed by a plateau, along with a contraction. LTD(4) increased the histamine-induced transient Ca(2+) peak and contraction but did not modify responses to carbachol. Enhanced responses to histamine induced by LTD(4) were not modified by staurosporine or chelerythrine but were abolished by genistein. Western blot showed that carbachol, but not histamine, caused intense phosphorylation of extracellular signal-regulated kinase 1/2 and that LTD(4) significantly enhanced the phosphorylation induced by histamine, but not by carbachol. L-type Ca(2+) channel participation in the hyperresponsiveness to histamine was discarded because LTD(4) did not modify the [Ca(2+)](i) changes induced by KCl. In tracheal myocytes, LTD(4) enhanced the transient Ca(2+) peak induced by histamine (but not by carbachol) and the sarcoplasmic reticulum (SR) Ca(2+) refilling. Genistein abolished this last LTD(4) effect. Partial blockade of the SR-ATPase Ca(2+) pump with cyclopiazonic acid reduced the Ca(2+) transient peak induced by histamine but not by carbachol. These results suggested that LTD(4) induces hyperresponsiveness to histamine through activation of the tyrosine kinase pathway and an increasing SR-ATPase Ca(2+) pump activity. L-type Ca(2+) channels seemed not to be involved in this phenomenon.
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Affiliation(s)
- Verónica Carbajal
- Departmento de Farmacología, Universidad Nacional Autónoma de México, México
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27
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Choe CU, Harrison KD, Grant W, Ehrlich BE. Functional Coupling of Chromogranin with the Inositol 1,4,5-Trisphosphate Receptor Shapes Calcium Signaling. J Biol Chem 2004; 279:35551-6. [PMID: 15194698 DOI: 10.1074/jbc.m311261200] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Chromogranins A and B are high capacity, low affinity calcium (Ca(2+)) storage proteins that bind to the inositol 1,4,5-trisphosphate-gated receptor (InsP(3) R). Although most commonly associated with secretory granules of neuroendocrine cells, chromogranins have also been found in the lumen of the endoplasmic reticulum (ER) of many cell types. To investigate the functional consequences of the interaction between the InsP(3) R and the chromogranins, we disrupted the interaction between the two proteins by adding a chromogranin fragment, which competed with chromogranin for its binding site on the InsP(3)R. Responses were monitored at the single channel level and in intact cells. When using InsP(3) R type I incorporated into planar lipid bilayers and activated by cytoplasmic InsP(3) and luminal chromogranin, the addition of the fragment reversed the enhancing effect of chromogranin. Moreover, the expression of the fragment in the ER of neuronally differentiated PC12 cells attenuated agonist-induced intracellular Ca(2+) signaling. These results show that the InsP(3)R/chromogranin interaction amplifies Ca(2+) release from the ER and that chromogranin is an essential component of this intracellular channel complex.
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Affiliation(s)
- Chi-Un Choe
- Department of Pharmacology and Cellular & Molecular Physiology, Yale University, New Haven, Connecticut 06520, USA
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28
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Thrower EC, Choe CU, So SH, Jeon SH, Ehrlich BE, Yoo SH. A Functional Interaction between Chromogranin B and the Inositol 1,4,5-Trisphosphate Receptor/Ca2+ Channel. J Biol Chem 2003; 278:49699-706. [PMID: 14506248 DOI: 10.1074/jbc.m309307200] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Chromogranins A and B (CGA and CGB) are high capacity, low affinity calcium (Ca2+) storage proteins found in many cell types most often associated with secretory granules of secretory cells but also with the endoplasmic reticulum (ER) lumen of these cells. Both CGA and CGB associate with inositol 1,4,5-trisphosphate receptor (InsP3R) in a pH-dependent manner. At an intraluminal pH of 5.5, as found in secretory vesicles, both CGA and CGB bind to the InsP3R. When the intraluminal pH is 7.5, as found in the ER, CGA totally dissociates from InsP3R, whereas CGB only partially dissociates. To investigate the functional consequences of the interaction between the InsP3R and CGB monomers or CGA/CGB heteromers, purified mouse InsP3R type I were fused to planar lipid bilayers and activated by 2 microM InsP3. In the presence of luminal CGB monomers or CGA/CGB heteromers the InsP3R/Ca2+ channel open probability and mean open time increased significantly. The channel activity remained elevated when the pH was changed to 7.5, a reflection of CGB binding to the InsP3R even at pH 7.5. These results suggest that CGB may play an important modulatory role in the control of Ca2+ release from the ER. Furthermore, the difference in the ability of CGA and CGB to regulate the InsP3R/Ca2+ channel and the variability of CGA/CGB ratios could influence the pattern of InsP3-mediated Ca2+ release.
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Affiliation(s)
- Edwin C Thrower
- Department of Pharmacology and Cellular and Molecular Physiology, Yale University, New Haven, Connecticut 06520, USA
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29
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Caroppo R, Colella M, Colasuonno A, DeLuisi A, Debellis L, Curci S, Hofer AM. A reassessment of the effects of luminal [Ca2+] on inositol 1,4,5-trisphosphate-induced Ca2+ release from internal stores. J Biol Chem 2003; 278:39503-8. [PMID: 12888563 DOI: 10.1074/jbc.m305823200] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Inositol 1,4,5-trisphosphate (InsP3)-induced Ca2+ release from intracellular stores displays complex kinetic behavior. While it well established that cytosolic [Ca2+] can modulate release by acting on the InsP3 receptor directly, the role of the filling state of internal Ca2+stores in modulating Ca2+ release remains unclear. Here we have reevaluated this topic using a technique that permits rapid and reversible changes in free [Ca2+] in internal stores of living intact cells without altering cytoplasmic [Ca2+], InsP3 receptors, or sarcoendoplasmic reticulum Ca2+ ATPases (SERCAs). N,N,N',N'-Tetrakis(2-pyridylmethyl)ethylene diamine (TPEN), a membrane-permeant, low affinity Ca2+ chelator was used to manipulate [Ca2+] in intracellular stores, while [Ca2+] changes within the store were monitored directly with the low-affinity Ca2+ indicator, mag-fura-2, in intact BHK-21 cells. 200 microM TPEN caused a rapid drop in luminal free [Ca2+] and significantly reduced the extent of the response to stimulation with 100 nm bradykinin, a calcium-mobilizing agonist. The same effect was observed when intact cells were pretreated with 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid(acetoxymethyl ester) (BAPTA-AM) to buffer cytoplasmic [Ca2+] changes. Although inhibition of Ca2+ uptake using the SERCA inhibitor tBHQ permitted significantly larger release of Ca2+ from stores, TPEN still attenuated the release in the presence of tBHQ in BAPTA-AM-loaded cells. These results demonstrate that the filling state of stores modulates the magnitude of InsP3-induced Ca2+release by additional mechanism(s) that are independent of regulation by cytoplasmic [Ca2+] or effects on SERCA pumps.
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Affiliation(s)
- Rosa Caroppo
- Dipartimento di Fisiologia Generale ed Ambientale, Università di Bari, Via Amendola 165/A 70126 Bari, Italy
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30
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Dawson AP, Lea EJA, Irvine RF. Kinetic model of the inositol trisphosphate receptor that shows both steady-state and quantal patterns of Ca2+ release from intracellular stores. Biochem J 2003; 370:621-9. [PMID: 12479792 PMCID: PMC1223205 DOI: 10.1042/bj20021289] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2002] [Revised: 12/04/2002] [Accepted: 12/13/2002] [Indexed: 11/17/2022]
Abstract
The release of Ca(2+) from intracellular stores via InsP(3) receptors shows anomalous kinetics. Successive additions of low concentrations of InsP(3) cause successive rapid transients of Ca(2+) release. These quantal responses have been ascribed to all-or-none release from stores with differing sensitivities to InsP(3) or, alternatively, to a steady-state mechanism where complex kinetic properties of the InsP(3) receptor allow partial emptying of all the stores. We present here an adaptive model of the InsP(3) receptor that can show either pattern, depending on the imposed experimental conditions. The model proposes two interconvertible conformational states of the receptor: one state binds InsP(3) rapidly, but with low affinity, whereas the other state binds slowly, but with high affinity. The model shows repetitive increments of Ca(2+) release in the absence of a Ca(2+) gradient, but more pronounced incremental behaviour when released Ca(2+) builds up at the mouth of the channel. The sensitivity to Ins P (3) is critically dependent on the density of InsP(3) receptors, so that different stores can respond to different concentration ranges of Ins P (3). Since the model generates very high Hill coefficients (h approximately 7), it allows all-or-none release of Ca(2+) from stores of differing receptor density, but questions the validity of the use of h values as a guide to the number of InsP(3) molecules needed to open the channel. The model presents a mechanism for terminating Ca(2+) release in the presence of positive feedback from released Ca(2+), thereby providing an explanation of why elementary Ca(2+) signals ('blips' and 'puffs') do not inevitably turn into regenerative waves.
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Affiliation(s)
- Alan P Dawson
- School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK.
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31
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Abstract
We propose here a unitary approach to the luminal and cytosolic control of calcium release. A minimal number of model elements that realistically describe different data sets are combined and adapted to correctly respond to various physiological constraints. We couple the kinetic properties of the inositol 1,4,5 trisphosphate receptor/calcium channel with the dynamics of Ca(2+) and K(+) in both the lumen and cytosol, and by using a detailed simulation approach, we propose that local (on a radial distance approximately 2 micro m) calcium oscillations in permeabilized cells are driven by the slow inactivation of channels organized in discrete clusters composed of between six and 15 channels. Moreover, the character of these oscillations is found to be extremely sensitive to K(+), so that the cytosolic and luminal calcium variations are in or out of phase if the store at equilibrium has tens or hundreds micro M Ca(2+), respectively, depending on the K(+) gradient across the reticulum membrane. Different patterns of calcium signals can be reproduced through variation of only a few parameters.
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Affiliation(s)
- Irina Baran
- Biophysics Department, Faculty of Medicine, Carol Davila University of Medicine and Pharmacology, 76241 Bucharest, Romania.
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32
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Dyer JL, Mobasheri H, Lea EJA, Dawson AP, Michelangeli F. Differential effect of PKA on the Ca2+ release kinetics of the type I and III InsP3 receptors. Biochem Biophys Res Commun 2003; 302:121-6. [PMID: 12593857 DOI: 10.1016/s0006-291x(03)00120-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The effects of protein kinase A (PKA) on the inositol 1,4,5-trisphosphate (InsP(3)) receptor isoforms type I and type III were studied. The effects of PKA on the extent and rate constants for InsP(3)-induced Ca(2+) release (IICR) were different for the two isoforms. The effects of PKA on the type I isoform showed a biphasic relationship dependent upon the concentration of PKA used. At low concentrations of PKA (<50U/ml), both the extent and rate constants for IICR increased, while at higher concentrations (>200U/ml) the extent and rate constants decreased. The type III isoform showed only an increase in the extent of IICR and not in the rate constants. The effects of PKA on the type I InsP(3) receptor using single channel electrophysiological studies were also investigated. The stimulatory effect of PKA is due to an increase in conductance levels and not to a change in the mean open time of the channel.
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Affiliation(s)
- Jeanette L Dyer
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
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Jiang QX, Thrower EC, Chester DW, Ehrlich BE, Sigworth FJ. Three-dimensional structure of the type 1 inositol 1,4,5-trisphosphate receptor at 24 A resolution. EMBO J 2002; 21:3575-81. [PMID: 12110570 PMCID: PMC126125 DOI: 10.1093/emboj/cdf380] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
We report here the first three-dimensional structure of the type 1 inositol 1,4,5-trisphosphate receptor (IP(3)R). From cryo-electron microscopic images of purified receptors embedded in vitreous ice, a three-dimensional structure was determined by use of standard single particle reconstruction techniques. The structure is strikingly different from that of the ryanodine receptor at similar resolution despite molecular similarities between these two calcium release channels. The 24 A resolution structure of the IP(3)R takes the shape of an uneven dumbbell, and is approximately 170 A tall. Its larger end is bulky, with four arms protruding laterally by approximately 50 A and, in comparison with the receptor topology, probably corresponds to the cytoplasmic domain of the receptor. The lateral dimension at the height of the protruding arms is approximately 155 A. The smaller end, whose lateral dimension is approximately 100 A, has structural features indicative of the membrane-spanning domain. A central opening in this domain, which is occluded on the cytoplasmic half, outlines a pathway for calcium flow in the open state of the channel.
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Affiliation(s)
- Qiu-Xing Jiang
- Departments of
Cellular and Molecular Physiology and Pharmacology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA Corresponding author e-mail:
| | - Edwin C. Thrower
- Departments of
Cellular and Molecular Physiology and Pharmacology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA Corresponding author e-mail:
| | - David W. Chester
- Departments of
Cellular and Molecular Physiology and Pharmacology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA Corresponding author e-mail:
| | - Barbara E. Ehrlich
- Departments of
Cellular and Molecular Physiology and Pharmacology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA Corresponding author e-mail:
| | - Fred J. Sigworth
- Departments of
Cellular and Molecular Physiology and Pharmacology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA Corresponding author e-mail:
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Hamada K, Miyata T, Mayanagi K, Hirota J, Mikoshiba K. Two-state conformational changes in inositol 1,4,5-trisphosphate receptor regulated by calcium. J Biol Chem 2002; 277:21115-8. [PMID: 11980893 DOI: 10.1074/jbc.c200244200] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Inositol 1,4,5-trisphosphate receptor (IP3R) is a highly controlled calcium (Ca2+) channel gated by inositol 1,4,5-trisphosphate (IP3). Multiple regulators modulate IP3-triggered pore opening by binding to discrete allosteric sites within IP3R. Accordingly we have postulated that these regulators structurally control ligand gating behavior; however, no structural evidence has been available. Here we show that Ca2+, the most pivotal regulator, induced marked structural changes in the tetrameric IP3R purified from mouse cerebella. Electron microscopy of the IP3R particles revealed two distinct structures with 4-fold symmetry: a windmill structure and a square structure. Ca2+ reversibly promoted a transition from the square to the windmill with relocations of four peripheral IP3-binding domains, assigned by binding to heparin-gold. Ca2+-dependent susceptibilities to limited digestion strongly support the notion that these alterations exist. Thus, Ca2+ appeared to regulate IP3 gating activity through the rearrangement of functional domains.
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Affiliation(s)
- Kozo Hamada
- Laboratory for Developmental Neurobiology, Brain Science Institute, RIKEN (The Institute of Physical and Chemical Research), 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan.
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Rueda A, García L, Guerrero-Hernández A. Luminal Ca(2+) and the activity of sarcoplasmic reticulum Ca(2+) pumps modulate histamine-induced all-or-none Ca(2+) release in smooth muscle cells. Cell Signal 2002; 14:517-27. [PMID: 11897492 DOI: 10.1016/s0898-6568(01)00284-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We have studied histamine (HA)-evoked intracellular Ca(2+) release in single, freshly isolated myocytes from the guinea pig urinary bladder. Short applications of histamine (5 s) produced a thapsigargin (TG)-sensitive transient increase in intracellular calcium concentration ([Ca(2+)](i)). It was established that histamine and caffeine (Caff) released Ca(2+) from the same intracellular stores in these cells. Reducing the Ca(2+) content of internal stores by incubating cells with U-73343 or cyclopiazonic acid (CPA) inhibited the histamine-evoked Ca(2+) release in 69% and 60% of cells, respectively. Under these conditions, all cells released Ca(2+) in response to either caffeine or acetylcholine (ACh). However, decreasing internal Ca(2+) stores by removing external Ca(2+) inhibited histamine-induced Ca(2+) mobilization in only 22% of cells. A similar small fraction of cells was inhibited when sarcoplasmic reticulum (SR) Ca(2+) pumps were quickly blocked to avoid a significant reduction of luminal Ca(2+). In conclusion, lowering the luminal Ca(2+) content in combination with an impairment of the SR Ca(2+) pump activity significantly diminishes the ability of histamine to evoke an all-or-none intracellular Ca(2+) release.
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Affiliation(s)
- Angélica Rueda
- Departamento de Bioquímica, CINVESTAV-IPN, Apdo. Postal 14-740, Mexico, D.F. 07000, Mexico
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Thrower EC, Park HY, So SH, Yoo SH, Ehrlich BE. Activation of the inositol 1,4,5-trisphosphate receptor by the calcium storage protein chromogranin A. J Biol Chem 2002; 277:15801-6. [PMID: 11842082 DOI: 10.1074/jbc.m110139200] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Secretory granules of neuroendocrine cells are inositol 1,4,5-trisphosphate (InsP(3))-sensitive Ca(2+) stores in which the Ca(2+) storage protein, chromogranin A (CGA), couples with InsP(3)-gated Ca(2+) channels (InsP(3)R) located in the granule membrane. The functional aspect of this coupling has been investigated via release studies and planar lipid bilayer experiments in the presence and absence of CGA. CGA drastically increased the release activity of the InsP(3)R by increasing the channel open probability by 9-fold and the mean open time by 12-fold. Our results show that CGA-coupled InsP(3)Rs are more sensitive to activation than uncoupled receptors. This modulation of InsP(3)R channel activity by CGA appears to be an essential component in the control of intracellular Ca(2+) concentration by secretory granules and may regulate the rate of vesicle fusion and exocytosis.
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Affiliation(s)
- Edwin C Thrower
- Department of Pharmacology, Yale University, New Haven, Connecticut 06520, USA.
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Dargan SL, Lea EJA, Dawson AP. Modulation of type-1 Ins(1,4,5)P3 receptor channels by the FK506-binding protein, FKBP12. Biochem J 2002; 361:401-7. [PMID: 11772413 PMCID: PMC1222321 DOI: 10.1042/0264-6021:3610401] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
FK506-binding protein (FKBP12) is highly expressed in neuronal tissue, where it is proposed to localize calcineurin to intracellular calcium-release channels, ryanodine receptors and Ins(1,4,5)P(3) receptors (InsP(3)Rs). The effects of FKBP12 on ryanodine receptors have been well characterized but the nature and function of binding of FKBP12 to InsP(3)R is more controversial, with evidence for and against a tight interaction between these two proteins. To investigate this, we incorporated purified type-1 InsP(3)R from rat cerebellum into planar lipid bilayers to monitor the effects of exogenous recombinant FKBP12 on single-channel activity, using K(+) as the current carrier. Here we report for the first time that FKBP12 causes a substantial change in single-channel properties of the type-1 InsP(3)R, specifically to increase the amount of time the channel spends in a fully open state. In the presence of ATP, FKBP12 can also induce co-ordinated gating with neighbouring receptors. The effects of FKBP12 were reversed by FK506. We also present data showing that rapamycin, at sub-optimal concentrations of Ins(2,4,5)P(3), decreases the rate of calcium release from cerebellar microsomes. These results provide evidence for a direct functional interaction between FKBP12 and the type-1 InsP(3)R.
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Affiliation(s)
- Sheila L Dargan
- School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK
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The lipid bilayer concept and its experimental realization: from soap bubbles, kitchen sink, to bilayer lipid membranes. J Memb Sci 2001. [DOI: 10.1016/s0376-7388(01)00394-5] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Tang J, Lin Y, Zhang Z, Tikunova S, Birnbaumer L, Zhu MX. Identification of common binding sites for calmodulin and inositol 1,4,5-trisphosphate receptors on the carboxyl termini of trp channels. J Biol Chem 2001; 276:21303-10. [PMID: 11290752 PMCID: PMC1847329 DOI: 10.1074/jbc.m102316200] [Citation(s) in RCA: 237] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Homologues of Drosophila Trp (transient receptor potential) form plasma membrane channels that mediate Ca(2+) entry following the activation of phospholipase C by cell surface receptors. Among the seven Trp homologous found in mammals, Trp3 has been shown to interact with and respond to IP(3) receptors (IP(3)Rs) for activation. Here we show that Trp4 and other Trp proteins also interact with IP(3)Rs. The IP(3)R-binding domain also interacts with calmodulin (CaM) in a Ca(2+)-dependent manner with affinities ranging from 10 nm for Trp2 to 290 nm for Trp6. In addition, other binding sites for CaM and IP(3)Rs are present in the alpha but not the beta isoform of Trp4. In the presence of Ca(2+), the Trp-IP(3)R interaction is inhibited by CaM. However, a synthetic peptide representing a Trp-binding domain of IP(3)Rs inhibited the binding of CaM to Trp3, -6, and -7 more effectively than that to Trp1, -2, -4, and -5. In inside-out membrane patches, Trp4 is activated strongly by calmidazolium, an antagonist of CaM, and a high (50 microm) but not a low (5 microm) concentration of the Trp-binding peptide of the IP(3)R. Our data support the view that both CaM and IP(3)Rs play important roles in controlling the gating of Trp-based channels. However, the sensitivity and responses to CaM and IP(3)Rs differ for each Trp.
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Affiliation(s)
- Jisen Tang
- Neurobiotechnology Center, Ohio State University, Columbus, Ohio 43210
| | - Yakang Lin
- Neurobiotechnology Center, Ohio State University, Columbus, Ohio 43210
| | - Zongming Zhang
- Neurobiotechnology Center, Ohio State University, Columbus, Ohio 43210
| | - Svetlana Tikunova
- Department of Neuroscience and Department of Molecular and Cellular Biochemistry, Ohio State University, Columbus, Ohio 43210
| | - Lutz Birnbaumer
- Departments of Anesthesiology, Biological Chemistry, and Molecular, Cellular, and Developmental Biology, UCLA, Los Angeles, California 90095
| | - Michael Xi Zhu
- Neurobiotechnology Center, Ohio State University, Columbus, Ohio 43210
- || To whom all correspondence should be addressed: The Ohio State University Neurobiotechnology Center, 168 Rightmire Hall, 1060 Carmack Rd., Columbus, OH 43210. Tel.: 614-292-8173; Fax: 614-292-5379; E-mail:
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