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Sneyers F, Speelman-Rooms F, Verhelst SHL, Bootman MD, Bultynck G. Cellular effects of BAPTA: Are they only about Ca 2+ chelation? BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2024; 1871:119589. [PMID: 37739271 DOI: 10.1016/j.bbamcr.2023.119589] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 09/06/2023] [Accepted: 09/10/2023] [Indexed: 09/24/2023]
Abstract
Intracellular Ca2+ signals play a vital role in a broad range of cell biological and physiological processes in all eukaryotic cell types. Dysregulation of Ca2+ signaling has been implicated in numerous human diseases. Over the past four decades, the understanding of how cells use Ca2+ as a messenger has flourished, largely because of the development of reporters that enable visualization of Ca2+ signals in different cellular compartments, and tools that can modulate cellular Ca2+ signaling. One such tool that is frequently used is BAPTA; a fast, high-affinity Ca2+-chelating molecule. By making use of a cell-permeable acetoxymethyl ester (AM) variant, BAPTA can be readily loaded into the cytosol of cells (referred to as BAPTAi), where it is trapped and able to buffer changes in cytosolic Ca2+. Due to the ease of loading of the AM version of BAPTA, this reagent has been used in hundreds of studies to probe the role of Ca2+ signaling in specific processes. As such, for decades, researchers have almost universally attributed changes in biological processes caused by BAPTAi to the involvement of Ca2+ signaling. However, BAPTAi has often been used without any form of control, and in many cases has neither been shown to be retained in cells for the duration of experiments nor to buffer any Ca2+ signals. Moreover, increasing evidence points to off-target cellular effects of BAPTA that are clearly not related to Ca2+ chelation. Here, we briefly introduce Ca2+ signaling and the history of Ca2+ chelators and fluorescent Ca2+ indicators. We highlight Ca2+-independent effects of BAPTAi on a broad range of molecular targets and describe some of BAPTAi's impacts on cell functions that occur independently of its Ca2+-chelating properties. Finally, we propose strategies for determining whether Ca2+ chelation, the binding of other metal ions, or off-target interactions with cell components are responsible for BAPTAi's effect on a particular process and suggest some future research directions.
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Affiliation(s)
- Flore Sneyers
- KU Leuven, Lab. Molecular & Cellular Signaling, Dep. Cellular & Molecular Medicine, Campus Gasthuisberg O/N-I bus 802, Herestraat 49, B-3000 Leuven, Belgium
| | - Femke Speelman-Rooms
- KU Leuven, Lab. Molecular & Cellular Signaling, Dep. Cellular & Molecular Medicine, Campus Gasthuisberg O/N-I bus 802, Herestraat 49, B-3000 Leuven, Belgium; KU Leuven, Department of Cellular and Molecular Medicine, Laboratory of Chemical Biology, Herestraat 49 box 901b, B-3000 Leuven, Belgium
| | - Steven H L Verhelst
- KU Leuven, Department of Cellular and Molecular Medicine, Laboratory of Chemical Biology, Herestraat 49 box 901b, B-3000 Leuven, Belgium
| | - Martin D Bootman
- The Open University, Cancer Research Group, School of Life, Health and Chemical Sciences, Milton Keynes, UK
| | - Geert Bultynck
- KU Leuven, Lab. Molecular & Cellular Signaling, Dep. Cellular & Molecular Medicine, Campus Gasthuisberg O/N-I bus 802, Herestraat 49, B-3000 Leuven, Belgium.
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Kolesnikov DO, Nomerovskaya MA, Grigorieva ER, Reshetin DS, Skobeleva KV, Gusev KO, Shalygin AV, Kaznacheyeva EV. Calcium chelation independent effects of BAPTA on endogenous ANO6 channels in HEK293T cells. Biochem Biophys Res Commun 2024; 693:149378. [PMID: 38100999 DOI: 10.1016/j.bbrc.2023.149378] [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: 11/17/2023] [Accepted: 12/09/2023] [Indexed: 12/17/2023]
Abstract
Selective calcium chelator 1,2-Bis(2-aminophenoxy) ethane-N,N,N',N'-tetraacetic acid (BAPTA) is a common tool to investigate calcium signaling. However, BAPTA expresses various effects on intracellular calcium signaling, which are not related to its ability to bind Ca2+. In patch clamp experiments, we investigated calcium chelation independent effects of BAPTA on endogenous calcium-activated chloride channels ANO6 (TMEM16F) in HEK293T cells. We have found that application of BAPTA to intracellular solution led to two distinct effects on channels properties. On the one hand, application of BAPTA acutely reduced amplitude of endogenous ANO6 channels induced by 10 μM Ca2+ in single channel recordings. On the other hand, BAPTA application by itself induced ANO6 channel activity in the absence of the intracellular calcium elevation. Open channel probability was enhanced by increasing the intracellular BAPTA concentration from 0.1 to 1 and 10 mM. Another calcium chelator EGTA did not demonstrate chelation independent effects on the ANO6 activity in the same conditions. Due to off-target effects BAPTA should be used with caution when studying calcium-activated ANO6 channels.
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Affiliation(s)
- D O Kolesnikov
- Institute of Cytology RAS, Tikhoretsky Ave. 4, St. Petersburg, 194064, Russian Federation
| | - M A Nomerovskaya
- Institute of Cytology RAS, Tikhoretsky Ave. 4, St. Petersburg, 194064, Russian Federation
| | - E R Grigorieva
- Institute of Cytology RAS, Tikhoretsky Ave. 4, St. Petersburg, 194064, Russian Federation
| | - D S Reshetin
- Institute of Cytology RAS, Tikhoretsky Ave. 4, St. Petersburg, 194064, Russian Federation
| | - K V Skobeleva
- Institute of Cytology RAS, Tikhoretsky Ave. 4, St. Petersburg, 194064, Russian Federation
| | - K O Gusev
- Institute of Cytology RAS, Tikhoretsky Ave. 4, St. Petersburg, 194064, Russian Federation
| | - A V Shalygin
- Institute of Cytology RAS, Tikhoretsky Ave. 4, St. Petersburg, 194064, Russian Federation.
| | - E V Kaznacheyeva
- Institute of Cytology RAS, Tikhoretsky Ave. 4, St. Petersburg, 194064, Russian Federation.
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Sneyers F, Kerkhofs M, Speelman-Rooms F, Welkenhuyzen K, La Rovere R, Shemy A, Voet A, Eelen G, Dewerchin M, Tait SWG, Ghesquière B, Bootman MD, Bultynck G. Intracellular BAPTA directly inhibits PFKFB3, thereby impeding mTORC1-driven Mcl-1 translation and killing MCL-1-addicted cancer cells. Cell Death Dis 2023; 14:600. [PMID: 37684238 PMCID: PMC10491774 DOI: 10.1038/s41419-023-06120-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 08/10/2023] [Accepted: 08/29/2023] [Indexed: 09/10/2023]
Abstract
Intracellular Ca2+ signals control several physiological and pathophysiological processes. The main tool to chelate intracellular Ca2+ is intracellular BAPTA (BAPTAi), usually introduced into cells as a membrane-permeant acetoxymethyl ester (BAPTA-AM). Previously, we demonstrated that BAPTAi enhanced apoptosis induced by venetoclax, a BCL-2 antagonist, in diffuse large B-cell lymphoma (DLBCL). This finding implied a novel interplay between intracellular Ca2+ signaling and anti-apoptotic BCL-2 function. Hence, we set out to identify the underlying mechanisms by which BAPTAi enhances cell death in B-cell cancers. In this study, we discovered that BAPTAi alone induced apoptosis in hematological cancer cell lines that were highly sensitive to S63845, an MCL-1 antagonist. BAPTAi provoked a rapid decline in MCL-1-protein levels by inhibiting mTORC1-driven Mcl-1 translation. These events were not a consequence of cell death, as BAX/BAK-deficient cancer cells exhibited similar downregulation of mTORC1 activity and MCL-1-protein levels. Next, we investigated how BAPTAi diminished mTORC1 activity and identified its ability to impair glycolysis by directly inhibiting 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3) activity, a previously unknown effect of BAPTAi. Notably, these effects were also induced by a BAPTAi analog with low affinity for Ca2+. Consequently, our findings uncover PFKFB3 inhibition as an Ca2+-independent mechanism through which BAPTAi impairs cellular metabolism and ultimately compromises the survival of MCL-1-dependent cancer cells. These findings hold two important implications. Firstly, the direct inhibition of PFKFB3 emerges as a key regulator of mTORC1 activity and a promising target in MCL-1-dependent cancers. Secondly, cellular effects caused by BAPTAi are not necessarily related to Ca2+ signaling. Our data support the need for a reassessment of the role of Ca2+ in cellular processes when findings were based on the use of BAPTAi.
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Affiliation(s)
- Flore Sneyers
- KU Leuven, Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine, Campus Gasthuisberg O&N I, Herestraat 49 box 802, 3000, Leuven, Belgium
| | - Martijn Kerkhofs
- KU Leuven, Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine, Campus Gasthuisberg O&N I, Herestraat 49 box 802, 3000, Leuven, Belgium
| | - Femke Speelman-Rooms
- KU Leuven, Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine, Campus Gasthuisberg O&N I, Herestraat 49 box 802, 3000, Leuven, Belgium
- KU Leuven, Laboratory of Chemical Biology, Department of Cellular and Molecular Medicine, Campus Gasthuisberg O&N I bis, Herestraat 49 box 901, 3000, Leuven, Belgium
| | - Kirsten Welkenhuyzen
- KU Leuven, Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine, Campus Gasthuisberg O&N I, Herestraat 49 box 802, 3000, Leuven, Belgium
| | - Rita La Rovere
- KU Leuven, Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine, Campus Gasthuisberg O&N I, Herestraat 49 box 802, 3000, Leuven, Belgium
| | - Ahmed Shemy
- KU Leuven, Laboratory for Biomolecular Modelling and Design, Department of Chemistry, Celestijnenlaan 200G, 3001, Heverlee, Belgium
| | - Arnout Voet
- KU Leuven, Laboratory for Biomolecular Modelling and Design, Department of Chemistry, Celestijnenlaan 200G, 3001, Heverlee, Belgium
| | - Guy Eelen
- KU Leuven, Laboratory of Angiogenesis and Vascular Metabolism, Department of Oncology, Leuven Cancer Institute, Campus Gasthuisberg O&N4, Herestraat 49 box 912, Leuven, Belgium
- VIB-KU Leuven, Center for Cancer Biology, Laboratory of Angiogenesis and Vascular Metabolism, Campus Gasthuisberg O&N4, Herestraat 49 box 912, 3000, Leuven, Belgium
| | - Mieke Dewerchin
- KU Leuven, Laboratory of Angiogenesis and Vascular Metabolism, Department of Oncology, Leuven Cancer Institute, Campus Gasthuisberg O&N4, Herestraat 49 box 912, Leuven, Belgium
- VIB-KU Leuven, Center for Cancer Biology, Laboratory of Angiogenesis and Vascular Metabolism, Campus Gasthuisberg O&N4, Herestraat 49 box 912, 3000, Leuven, Belgium
| | - Stephen W G Tait
- Cancer Research UK Beatson Institute, School of Cancer Sciences, University of Glasgow, Glasgow, UK
| | - Bart Ghesquière
- KU Leuven, Laboratory of Applied Mass Spectrometry, Department of Cellular and Molecular Medicine, Leuven, Belgium - VIB, Metabolomics Core Facility Leuven, Center for Cancer Biology, Leuven, Belgium, Herestraat 49 box 912, 3000, Leuven, Belgium
| | - Martin D Bootman
- School of Life, Health and Chemical Sciences, Faculty of Science, Technology, Engineering and Mathematics, The Open University, Walton Hall, Milton Keynes, MK7 6AA, UK.
| | - Geert Bultynck
- KU Leuven, Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine, Campus Gasthuisberg O&N I, Herestraat 49 box 802, 3000, Leuven, Belgium.
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Kaur N, Prashanth KH, Bhatti MS, Pati PK. OsSalT gene cloned from rice provides evidence of its role in salinity and drought stress tolerance. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2022; 320:111306. [PMID: 35643601 DOI: 10.1016/j.plantsci.2022.111306] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 03/31/2022] [Accepted: 04/28/2022] [Indexed: 06/15/2023]
Abstract
Abiotic stresses impose a huge threat to agricultural productivity and global food security. To counter this challenge, the precise identification of the right candidate gene (s) for conferring abiotic stress tolerance without compromising the growth and yield is crucial. OsSalT is identified as a salt stress responsive gene located on SalTol QTL of chromosome 1 of rice, however, there is no genetic evidence of its function and probable pathway of its regulation. To get better insights into its functioning, earlier we elucidated the structure of SALT protein at atomic scale {PDB ID (5GVY)} and solution state that provided key clues on the probable mode of its action. Herein, we report the modulation of OsSalT gene in response to various factors and its functional characterization. Results indicate that OsSalT operates through both abscisic acid and gibberellic acid-dependent pathways and is linked to the adaptive stress mechanisms of plants. Its overexpression in a model plant resulted in improved salinity and drought stress tolerance. The OsSalT transformed plants also showed vigorous root growth, early flowering, and better seed germination. The triggering of multiple responses by OsSalT suggested that modulation of such mannose-binding lectin could be a potential game-changer for the improvement of many crops in future.
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Affiliation(s)
- Navdeep Kaur
- Department of Biotechnology, Guru Nanak Dev University, Amritsar, Punjab 143005, India.
| | | | - Manpreet Singh Bhatti
- Department of Botanical & Environmental Sciences, Guru Nanak Dev University, Amritsar, Punjab 143005, India.
| | - Pratap Kumar Pati
- Department of Biotechnology, Guru Nanak Dev University, Amritsar, Punjab 143005, India.
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L-type Voltage-Gated Calcium Channel Modulators Inhibit Glutamate-Induced Morphology Changes in U118-MG Astrocytoma Cells. Cell Mol Neurobiol 2020; 40:1429-1437. [PMID: 32172458 DOI: 10.1007/s10571-020-00828-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 03/06/2020] [Indexed: 10/24/2022]
Abstract
The excitatory neurotransmitter glutamate evokes physiological responses within the astrocytic network that lead to fine morphological changes. However, the mechanism by which astrocytes couple glutamate sensing with cellular calcium rise remains unclear. We tested a possible connection between L-type voltage-gated calcium channels (Cav) and glutamate-induced response in U118-MG astrocytoma cells. While astrocytoma cells differ from primary astrocytes, they demonstrate the same response to glutamate. In this study, the extension of U118-MG processes upon glutamate exposure was shown to depend on extracellular calcium entry via L-type Cav's. Drugs known to bind to the pore-forming subunit of Cav's decreased the astrocytic filopodia extension caused by glutamate, and ligands of the α2δ auxiliary subunit inhibited all process growth (e.g., gabapentinoids). The observed phenotypic responses suggest that α2δ is a main contributor to the role of Cavs in glutamate-dependent filopodiagenesis, thereby opening new avenues of research on the role of α2δ in astrocytic neurochemical signaling.
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Bootman MD, Allman S, Rietdorf K, Bultynck G. Deleterious effects of calcium indicators within cells; an inconvenient truth. Cell Calcium 2018; 73:82-87. [DOI: 10.1016/j.ceca.2018.04.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2018] [Revised: 04/03/2018] [Accepted: 04/11/2018] [Indexed: 01/20/2023]
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7
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De Vriese K, Costa A, Beeckman T, Vanneste S. Pharmacological Strategies for Manipulating Plant Ca 2+ Signalling. Int J Mol Sci 2018; 19:E1506. [PMID: 29783646 PMCID: PMC5983822 DOI: 10.3390/ijms19051506] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 05/10/2018] [Accepted: 05/12/2018] [Indexed: 11/20/2022] Open
Abstract
Calcium is one of the most pleiotropic second messengers in all living organisms. However, signalling specificity is encoded via spatio-temporally regulated signatures that act with surgical precision to elicit highly specific cellular responses. How this is brought about remains a big challenge in the plant field, in part due to a lack of specific tools to manipulate/interrogate the plant Ca2+ toolkit. In many cases, researchers resort to tools that were optimized in animal cells. However, the obviously large evolutionary distance between plants and animals implies that there is a good chance observed effects may not be specific to the intended plant target. Here, we provide an overview of pharmacological strategies that are commonly used to activate or inhibit plant Ca2+ signalling. We focus on highlighting modes of action where possible, and warn for potential pitfalls. Together, this review aims at guiding plant researchers through the Ca2+ pharmacology swamp.
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Affiliation(s)
- Kjell De Vriese
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, 9052 Ghent, Belgium.
- VIB Center for Plant Systems Biology, VIB, Technologiepark 927, 9052 Ghent, Belgium.
| | - Alex Costa
- Department of Biosciences, University of Milan, 20133 Milan, Italy.
- Instititute of Biophysics, Consiglio Nazionale delle Ricerche, 20133 Milan, Italy.
| | - Tom Beeckman
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, 9052 Ghent, Belgium.
- VIB Center for Plant Systems Biology, VIB, Technologiepark 927, 9052 Ghent, Belgium.
| | - Steffen Vanneste
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, 9052 Ghent, Belgium.
- VIB Center for Plant Systems Biology, VIB, Technologiepark 927, 9052 Ghent, Belgium.
- Lab of Plant Growth Analysis, Ghent University Global Campus, Songdomunhwa-Ro, 119, Yeonsu-gu, Incheon 21985, Korea.
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Murana E, Pagani F, Basilico B, Sundukova M, Batti L, Di Angelantonio S, Cortese B, Grimaldi A, Francioso A, Heppenstall P, Bregestovski P, Limatola C, Ragozzino D. ATP release during cell swelling activates a Ca 2+-dependent Cl - current by autocrine mechanism in mouse hippocampal microglia. Sci Rep 2017. [PMID: 28646166 PMCID: PMC5482828 DOI: 10.1038/s41598-017-04452-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Microglia cells, resident immune cells of the brain, survey brain parenchyma by dynamically extending and retracting their processes. Cl− channels, activated in the cellular response to stretch/swelling, take part in several functions deeply connected with microglia physiology, including cell shape changes, proliferation, differentiation and migration. However, the molecular identity and functional properties of these Cl− channels are largely unknown. We investigated the properties of swelling-activated currents in microglial from acute hippocampal slices of Cx3cr1+/GFP mice by whole-cell patch-clamp and imaging techniques. The exposure of cells to a mild hypotonic medium, caused an outward rectifying current, developing in 5–10 minutes and reverting upon stimulus washout. This current, required for microglia ability to extend processes towards a damage signal, was carried mainly by Cl− ions and dependent on intracellular Ca2+. Moreover, it involved swelling-induced ATP release. We identified a purine-dependent mechanism, likely constituting an amplification pathway of current activation: under hypotonic conditions, ATP release triggered the Ca2+-dependent activation of anionic channels by autocrine purine receptors stimulation. Our study on native microglia describes for the first time the functional properties of stretch/swelling-activated currents, representing a key element in microglia ability to monitor the brain parenchyma.
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Affiliation(s)
- E Murana
- Department of Physiology and Pharmacology, Sapienza University, Rome, Italy
| | - F Pagani
- Istituto Italiano di Tecnologia, CLNS@Sapienza, Rome, Italy.
| | - B Basilico
- Department of Physiology and Pharmacology, Sapienza University, Rome, Italy
| | - M Sundukova
- Mouse Biology Unit, EMBL, Monterotondo, Italy
| | - L Batti
- Mouse Biology Unit, EMBL, Monterotondo, Italy
| | - S Di Angelantonio
- Department of Physiology and Pharmacology, Sapienza University, Rome, Italy.,Istituto Italiano di Tecnologia, CLNS@Sapienza, Rome, Italy
| | - B Cortese
- CNR NANOTEC - Istituto di Nanotecnologia, Department of Physics, University Sapienza, Rome, Italy
| | - A Grimaldi
- Istituto Italiano di Tecnologia, CLNS@Sapienza, Rome, Italy
| | - A Francioso
- Department of Biochemistry, "Sapienza" University of Rome, Rome, Italy
| | | | - P Bregestovski
- Aix Marseille University, Inserm, INS, Institut de Neurosciences des Systèmes, Marseille, France
| | - C Limatola
- IRCCS Neuromed, Via Atinese, Pozzilli, Italy.,Pasteur Institute - Department of Physiology and Pharmacology, Sapienza University, Rome, Italy
| | - D Ragozzino
- Department of Physiology and Pharmacology, Sapienza University, Rome, Italy.,IRCCS Neuromed, Via Atinese, Pozzilli, Italy
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Liu B, Yao J, Zhu MX, Qin F. Hysteresis of gating underlines sensitization of TRPV3 channels. ACTA ACUST UNITED AC 2011; 138:509-20. [PMID: 22006988 PMCID: PMC3206302 DOI: 10.1085/jgp.201110689] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Vanilloid receptors of the transient receptor potential family have functions in thermal sensation and nociception. Among them, transient receptor potential vanilloid (TRPV)3 displays a unique property by which the repeated stimulation causes successive increases in its activity. The property has been known as sensitization and is observed in both native cells and cells heterologously expressing TRPV3. Transient increases in intracellular calcium levels have been implicated to play a key role in this process by mediating interaction of calmodulin with the channel. In support of the mechanism, BAPTA, a fast calcium chelator, accelerates the sensitization, whereas the slow chelator EGTA is ineffectual. Here, we show that the sensitization of TRPV3 also occurred independently of Ca2+. It was observed in both inside-out and outside-out membrane patches. BAPTA, but not EGTA, has a direct potentiation effect on channel activation. Analogues of BAPTA lacking Ca2+-buffering capability were similarly effective. The stimulation-induced sensitization and the potentiation by BAPTA are distinguishable in reversibility. We conclude that the sensitization of TRPV3 is intrinsic to the channel itself and occurs as a result of hysteresis of channel gating. BAPTA accelerates the sensitization process by potentiating the gating of the channel.
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Affiliation(s)
- Beiying Liu
- Department of Physiology and Biophysical Sciences, State University of New York at Buffalo, Buffalo, NY 14214, USA
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