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Arancibia F, De Giorgis D, Medina F, Hermosilla T, Simon F, Varela D. Role of the Ca V1.2 distal carboxy terminus in the regulation of L-type current. Channels (Austin) 2024; 18:2338782. [PMID: 38691022 PMCID: PMC11067984 DOI: 10.1080/19336950.2024.2338782] [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: 02/15/2024] [Accepted: 03/31/2024] [Indexed: 05/03/2024] Open
Abstract
L-type calcium channels are essential for the excitation-contraction coupling in cardiac muscle. The CaV1.2 channel is the most predominant isoform in the ventricle which consists of a multi-subunit membrane complex that includes the CaV1.2 pore-forming subunit and auxiliary subunits like CaVα2δ and CaVβ2b. The CaV1.2 channel's C-terminus undergoes proteolytic cleavage, and the distal C-terminal domain (DCtermD) associates with the channel core through two domains known as proximal and distal C-terminal regulatory domain (PCRD and DCRD, respectively). The interaction between the DCtermD and the remaining C-terminus reduces the channel activity and modifies voltage- and calcium-dependent inactivation mechanisms, leading to an autoinhibitory effect. In this study, we investigate how the interaction between DCRD and PCRD affects the inactivation processes and CaV1.2 activity. We expressed a 14-amino acid peptide miming the DCRD-PCRD interaction sequence in both heterologous systems and cardiomyocytes. Our results show that overexpression of this small peptide can displace the DCtermD and replicate the effects of the entire DCtermD on voltage-dependent inactivation and channel inhibition. However, the effect on calcium-dependent inactivation requires the full DCtermD and is prevented by overexpression of calmodulin. In conclusion, our results suggest that the interaction between DCRD and PCRD is sufficient to bring about the current inhibition and alter the voltage-dependent inactivation, possibly in an allosteric manner. Additionally, our data suggest that the DCtermD competitively modifies the calcium-dependent mechanism. The identified peptide sequence provides a valuable tool for further dissecting the molecular mechanisms that regulate L-type calcium channels' basal activity in cardiomyocytes.
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Affiliation(s)
- Felipe Arancibia
- Millennium Nucleus of Ion Channels-Associated Diseases (MiNICAD), Universidad de Chile, Santiago, Chile
- Programa de Fisiología y Biofísica, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Daniela De Giorgis
- Millennium Nucleus of Ion Channels-Associated Diseases (MiNICAD), Universidad de Chile, Santiago, Chile
- Programa de Fisiología y Biofísica, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Franco Medina
- Millennium Nucleus of Ion Channels-Associated Diseases (MiNICAD), Universidad de Chile, Santiago, Chile
- Programa de Fisiología y Biofísica, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Tamara Hermosilla
- Millennium Nucleus of Ion Channels-Associated Diseases (MiNICAD), Universidad de Chile, Santiago, Chile
- Programa de Fisiología y Biofísica, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Felipe Simon
- Millennium Nucleus of Ion Channels-Associated Diseases (MiNICAD), Universidad de Chile, Santiago, Chile
- Laboratory of Integrative Physiopathology, Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
| | - Diego Varela
- Millennium Nucleus of Ion Channels-Associated Diseases (MiNICAD), Universidad de Chile, Santiago, Chile
- Programa de Fisiología y Biofísica, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
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Xu B, Bahriz S, Salemme VR, Wang Y, Zhu C, Zhao M, Xiang YK. Differential Downregulation of β 1-Adrenergic Receptor Signaling in the Heart. J Am Heart Assoc 2024; 13:e033733. [PMID: 38860414 PMCID: PMC11255761 DOI: 10.1161/jaha.123.033733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 05/15/2024] [Indexed: 06/12/2024]
Abstract
BACKGROUND Chronic sympathetic stimulation drives desensitization and downregulation of β1 adrenergic receptor (β1AR) in heart failure. We aim to explore the differential downregulation subcellular pools of β1AR signaling in the heart. METHODS AND RESULTS We applied chronic infusion of isoproterenol to induced cardiomyopathy in male C57BL/6J mice. We applied confocal and proximity ligation assay to examine β1AR association with L-type calcium channel, ryanodine receptor 2, and SERCA2a ((Sarco)endoplasmic reticulum calcium ATPase 2a) and Förster resonance energy transfer-based biosensors to probe subcellular β1AR-PKA (protein kinase A) signaling in ventricular myocytes. Chronic infusion of isoproterenol led to reduced β1AR protein levels, receptor association with L-type calcium channel and ryanodine receptor 2 measured by proximity ligation (puncta/cell, 29.65 saline versus 14.17 isoproterenol, P<0.05), and receptor-induced PKA signaling at the plasma membrane (Förster resonance energy transfer, 28.9% saline versus 1.9% isoproterenol, P<0.05) and ryanodine receptor 2 complex (Förster resonance energy transfer, 30.2% saline versus 10.6% isoproterenol, P<0.05). However, the β1AR association with SERCA2a was enhanced (puncta/cell, 51.4 saline versus 87.5 isoproterenol, P<0.05), and the receptor signal was minimally affected. The isoproterenol-infused hearts displayed decreased PDE4D (phosphodiesterase 4D) and PDE3A and increased PDE2A, PDE4A, and PDE4B protein levels. We observed a reduced role of PDE4 and enhanced roles of PDE2 and PDE3 on the β1AR-PKA activity at the ryanodine receptor 2 complexes and myocyte shortening. Despite the enhanced β1AR association with SERCA2a, the endogenous norepinephrine-induced signaling was reduced at the SERCA2a complexes. Inhibiting monoamine oxidase A rescued the norepinephrine-induced PKA signaling at the SERCA2a and myocyte shortening. CONCLUSIONS This study reveals distinct mechanisms for the downregulation of subcellular β1AR signaling in the heart under chronic adrenergic stimulation.
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Affiliation(s)
- Bing Xu
- VA Northern California Health Care SystemMatherCAUSA
- Department of PharmacologyUniversity of California at DavisDavisCAUSA
| | - Sherif Bahriz
- Department of PharmacologyUniversity of California at DavisDavisCAUSA
- Department of Clinical Pathology, Faculty of MedicineMansoura UniversityMansouraEgypt
| | | | - Ying Wang
- Department of PharmacologyUniversity of California at DavisDavisCAUSA
- Department of Pharmacology, School of MedicineSouthern University of Science and TechnologyShenzhenChina
| | - Chaoqun Zhu
- Department of PharmacologyUniversity of California at DavisDavisCAUSA
| | - Meimi Zhao
- Department of PharmacologyUniversity of California at DavisDavisCAUSA
- Department of Pharmaceutical ToxicologyChina Medical UniversityShenyangChina
| | - Yang K. Xiang
- VA Northern California Health Care SystemMatherCAUSA
- Department of PharmacologyUniversity of California at DavisDavisCAUSA
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3
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Maziar A, Critch TNRHY, Ghosh S, Rajani V, Flynn CM, Qin T, Reinhardt C, Man KNM, Lee A, Hell JW, Yuan Q. Aging differentially affects LTCC function in hippocampal CA1 and piriform cortex pyramidal neurons. Cereb Cortex 2023; 33:1489-1503. [PMID: 35437602 PMCID: PMC9930631 DOI: 10.1093/cercor/bhac152] [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: 01/20/2022] [Revised: 03/25/2022] [Accepted: 03/27/2022] [Indexed: 11/14/2022] Open
Abstract
Aging is associated with cognitive decline and memory loss in humans. In rats, aging-associated neuronal excitability changes and impairments in learning have been extensively studied in the hippocampus. Here, we investigated the roles of L-type calcium channels (LTCCs) in the rat piriform cortex (PC), in comparison with those of the hippocampus. We employed spatial and olfactory tasks that involve the hippocampus and PC. LTCC blocker nimodipine administration impaired spontaneous location recognition in adult rats (6-9 months). However, the same blocker rescued the spatial learning deficiency in aged rats (19-23 months). In an odor-associative learning task, infusions of nimodipine into either the PC or dorsal CA1 impaired the ability of adult rats to learn a positive odor association. Again, in contrast, nimodipine rescued odor associative learning in aged rats. Aged CA1 neurons had higher somatic expression of LTCC Cav1.2 subunits, exhibited larger afterhyperpolarization (AHP) and lower excitability compared with adult neurons. In contrast, PC neurons from aged rats showed higher excitability and no difference in AHP. Cav1.2 expression was similar in adult and aged PC somata, but relatively higher in PSD95- puncta in aged dendrites. Our data suggest unique features of aging-associated changes in LTCCs in the PC and hippocampus.
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Affiliation(s)
- Aida Maziar
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, St. John's, NL A1B 3V6, Canada
| | - Tristian N R H Y Critch
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, St. John's, NL A1B 3V6, Canada
| | - Sourav Ghosh
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, St. John's, NL A1B 3V6, Canada
| | - Vishaal Rajani
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, St. John's, NL A1B 3V6, Canada
| | - Cassandra M Flynn
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, St. John's, NL A1B 3V6, Canada
| | - Tian Qin
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, St. John's, NL A1B 3V6, Canada
| | - Camila Reinhardt
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, St. John's, NL A1B 3V6, Canada
| | - Kwun Nok Mimi Man
- Department of Pharmacology, School of Medicine, University of California-Davis, Sacramento, CA 95817, United States
| | - Amy Lee
- Department of Neuroscience, University of Texas-Austin, Austin, TX 78712, United States
| | - Johannes W Hell
- Department of Pharmacology, School of Medicine, University of California-Davis, Sacramento, CA 95817, United States
| | - Qi Yuan
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, St. John's, NL A1B 3V6, Canada
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4
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Klomp AJ, Plumb A, Mehr JB, Madencioglu DA, Wen H, Williams AJ. Neuronal deletion of Ca V1.2 is associated with sex-specific behavioral phenotypes in mice. Sci Rep 2022; 12:22152. [PMID: 36550186 PMCID: PMC9780340 DOI: 10.1038/s41598-022-26504-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 12/15/2022] [Indexed: 12/24/2022] Open
Abstract
The gene CACNA1C, which encodes the pore forming subunit of the L-type calcium channel CaV1.2, is associated with increased risk for neuropsychiatric disorders including schizophrenia, autism spectrum disorder, major depression, and bipolar disorder. Previous rodent work identified that loss or reduction of CaV1.2 results in cognitive, affective, and motor deficits. Most previous work has either included non-neuronal cell populations (haploinsufficient and Nestin-Cre) or investigated a discrete neuronal cell population (e.g. CaMKII-Cre, Drd1-Cre), but few studies have examined the effects of more broad neuron-specific deletion of CaV1.2. Additionally, most of these studies did not evaluate for sex-specific effects or used only male animals. Here, we sought to clarify whether there are sex-specific behavioral consequences of neuron-specific deletion of CaV1.2 (neuronal CaV1.2 cKO) using Syn1-Cre-mediated conditional deletion. We found that neuronal CaV1.2 cKO mice have normal baseline locomotor function but female cKO mice display impaired motor performance learning. Male neuronal CaV1.2 cKO display impaired startle response with intact pre-pulse inhibition. Male neuronal CaV1.2 cKO mice did not display normal social preference, whereas female neuronal CaV1.2 cKO mice did. Neuronal CaV1.2 cKO mice displayed impaired associative learning in both sexes, as well as normal anxiety-like behavior and hedonic capacity. We conclude that deletion of neuronal CaV1.2 alters motor performance, acoustic startle reflex, and social behaviors in a sex-specific manner, while associative learning deficits generalize across sexes. Our data provide evidence for both sex-specific and sex-independent phenotypes related to neuronal expression of CaV1.2.
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Affiliation(s)
- Annette J Klomp
- Iowa Neuroscience Institute, University of Iowa, Iowa City, IA, USA
- Department of Psychiatry, University of Iowa, Iowa City, IA, USA
| | - Ashley Plumb
- Department of Physical Therapy and Rehabilitation Science, University of Iowa, Iowa City, IA, USA
| | - Jacqueline B Mehr
- Department of Psychiatry, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ, USA
- Brain Health Institute, Rutgers University, Piscataway, NJ, USA
| | - Deniz A Madencioglu
- Iowa Neuroscience Institute, University of Iowa, Iowa City, IA, USA
- Department of Psychiatry, University of Iowa, Iowa City, IA, USA
| | - Hsiang Wen
- Iowa Neuroscience Institute, University of Iowa, Iowa City, IA, USA
- Department of Psychiatry, University of Iowa, Iowa City, IA, USA
| | - Aislinn J Williams
- Iowa Neuroscience Institute, University of Iowa, Iowa City, IA, USA.
- Department of Psychiatry, University of Iowa, Iowa City, IA, USA.
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5
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Bartels P, Salveson I, Coleman AM, Anderson DE, Jeng G, Estrada-Tobar ZM, Man KNM, Yu Q, Kuzmenkina E, Nieves-Cintron M, Navedo MF, Horne MC, Hell JW, Ames JB. Half-calcified calmodulin promotes basal activity and inactivation of the L-type calcium channel Ca V1.2. J Biol Chem 2022; 298:102701. [PMID: 36395884 PMCID: PMC9764201 DOI: 10.1016/j.jbc.2022.102701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 10/30/2022] [Accepted: 10/31/2022] [Indexed: 11/17/2022] Open
Abstract
The L-type Ca2+ channel CaV1.2 controls gene expression, cardiac contraction, and neuronal activity. Calmodulin (CaM) governs CaV1.2 open probability (Po) and Ca2+-dependent inactivation (CDI) but the mechanisms remain unclear. Here, we present electrophysiological data that identify a half Ca2+-saturated CaM species (Ca2/CaM) with Ca2+ bound solely at the third and fourth EF-hands (EF3 and EF4) under resting Ca2+ concentrations (50-100 nM) that constitutively preassociates with CaV1.2 to promote Po and CDI. We also present an NMR structure of a complex between the CaV1.2 IQ motif (residues 1644-1665) and Ca2/CaM12', a calmodulin mutant in which Ca2+ binding to EF1 and EF2 is completely disabled. We found that the CaM12' N-lobe does not interact with the IQ motif. The CaM12' C-lobe bound two Ca2+ ions and formed close contacts with IQ residues I1654 and Y1657. I1654A and Y1657D mutations impaired CaM binding, CDI, and Po, as did disabling Ca2+ binding to EF3 and EF4 in the CaM34 mutant when compared to WT CaM. Accordingly, a previously unappreciated Ca2/CaM species promotes CaV1.2 Po and CDI, identifying Ca2/CaM as an important mediator of Ca signaling.
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Affiliation(s)
- Peter Bartels
- Department of Pharmacology, University of California, Davis, California, USA
| | - Ian Salveson
- Department of Chemistry, University of California, Davis, California, USA
| | - Andrea M Coleman
- Department of Pharmacology, University of California, Davis, California, USA; Department of Chemistry, University of California, Davis, California, USA
| | - David E Anderson
- Department of Chemistry, University of California, Davis, California, USA
| | - Grace Jeng
- Department of Pharmacology, University of California, Davis, California, USA
| | | | - Kwun Nok Mimi Man
- Department of Pharmacology, University of California, Davis, California, USA
| | - Qinhong Yu
- Department of Chemistry, University of California, Davis, California, USA
| | - Elza Kuzmenkina
- Center for Pharmacology, University of Cologne, Cologne, Germany
| | | | - Manuel F Navedo
- Department of Pharmacology, University of California, Davis, California, USA
| | - Mary C Horne
- Department of Pharmacology, University of California, Davis, California, USA.
| | - Johannes W Hell
- Department of Pharmacology, University of California, Davis, California, USA.
| | - James B Ames
- Department of Chemistry, University of California, Davis, California, USA.
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6
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Park DK, Petshow S, Anisimova M, Barragan EV, Gray JA, Stein IS, Zito K. Reduced d-serine levels drive enhanced non-ionotropic NMDA receptor signaling and destabilization of dendritic spines in a mouse model for studying schizophrenia. Neurobiol Dis 2022; 170:105772. [PMID: 35605760 PMCID: PMC9352378 DOI: 10.1016/j.nbd.2022.105772] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Revised: 05/15/2022] [Accepted: 05/16/2022] [Indexed: 10/31/2022] Open
Abstract
Schizophrenia is a psychiatric disorder that affects over 20 million people globally. Notably, schizophrenia is associated with decreased density of dendritic spines and decreased levels of d-serine, a co-agonist required for opening of the N-methyl-d-aspartate receptor (NMDAR). We hypothesized that lowered d-serine levels associated with schizophrenia would enhance ion flux-independent signaling by the NMDAR, driving destabilization and loss of dendritic spines. We tested our hypothesis using the serine racemase knockout (SRKO) mouse model, which lacks the enzyme for d-serine production. We show that activity-dependent spine growth is impaired in SRKO mice, but can be acutely rescued by exogenous d-serine. Moreover, we find a significant bias of synaptic plasticity toward spine shrinkage in the SRKO mice as compared to wild-type littermates. Notably, we demonstrate that enhanced ion flux-independent signaling through the NMDAR contributes to this bias toward spine destabilization, which is exacerbated by an increase in synaptic NMDARs in hippocampal synapses of SRKO mice. Our results support a model in which lowered d-serine levels associated with schizophrenia enhance ion flux-independent NMDAR signaling and bias toward spine shrinkage and destabilization.
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7
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Erdogmus S, Concepcion AR, Yamashita M, Sidhu I, Tao AY, Li W, Rocha PP, Huang B, Garippa R, Lee B, Lee A, Hell JW, Lewis RS, Prakriya M, Feske S. Cavβ1 regulates T cell expansion and apoptosis independently of voltage-gated Ca 2+ channel function. Nat Commun 2022; 13:2033. [PMID: 35440113 PMCID: PMC9018955 DOI: 10.1038/s41467-022-29725-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 03/22/2022] [Indexed: 12/11/2022] Open
Abstract
TCR stimulation triggers Ca2+ signals that are critical for T cell function and immunity. Several pore-forming α and auxiliary β subunits of voltage-gated Ca2+ channels (VGCC) were reported in T cells, but their mechanism of activation remains elusive and their contribution to Ca2+ signaling in T cells is controversial. We here identify CaVβ1, encoded by Cacnb1, as a regulator of T cell function. Cacnb1 deletion enhances apoptosis and impairs the clonal expansion of T cells after lymphocytic choriomeningitis virus (LCMV) infection. By contrast, Cacnb1 is dispensable for T cell proliferation, cytokine production and Ca2+ signaling. Using patch clamp electrophysiology and Ca2+ recordings, we are unable to detect voltage-gated Ca2+ currents or Ca2+ influx in human and mouse T cells upon depolarization with or without prior TCR stimulation. mRNAs of several VGCC α1 subunits are detectable in human (CaV3.3, CaV3.2) and mouse (CaV2.1) T cells, but they lack transcription of many 5' exons, likely resulting in N-terminally truncated and non-functional proteins. Our findings demonstrate that although CaVβ1 regulates T cell function, these effects are independent of VGCC channel activity.
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Affiliation(s)
- Serap Erdogmus
- Department of Pathology, NYU Grossman School of Medicine, New York, NY, USA
| | - Axel R Concepcion
- Department of Pathology, NYU Grossman School of Medicine, New York, NY, USA
| | - Megumi Yamashita
- Department of Pharmacology, Northwestern University, Chicago, IL, USA
| | - Ikjot Sidhu
- Department of Pathology, NYU Grossman School of Medicine, New York, NY, USA
| | - Anthony Y Tao
- Department of Pathology, NYU Grossman School of Medicine, New York, NY, USA
| | - Wenyi Li
- Department of Pathology, NYU Grossman School of Medicine, New York, NY, USA
| | - Pedro P Rocha
- Unit on Genome Structure and Regulation, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
- National Cancer Institute, NIH, Bethesda, MD, USA
| | - Bonnie Huang
- National Institute of Allergy and Infectious Disease, Bethesda, MD, USA
- National Human Genome Research Institute, Bethesda, MD, USA
| | - Ralph Garippa
- Department of Cancer Biology & Genetics, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Boram Lee
- Department of Pharmacology, University of California, Davis, CA, USA
| | - Amy Lee
- Department of Neuroscience, University of Texas-Austin, Austin, TX, USA
| | - Johannes W Hell
- Department of Pharmacology, University of California, Davis, CA, USA
| | - Richard S Lewis
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA
| | - Murali Prakriya
- Department of Pharmacology, Northwestern University, Chicago, IL, USA.
| | - Stefan Feske
- Department of Pathology, NYU Grossman School of Medicine, New York, NY, USA.
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8
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Kadurin I, Dahimene S, Page KM, Ellaway JIJ, Chaggar K, Troeberg L, Nagase H, Dolphin AC. ADAM17 Mediates Proteolytic Maturation of Voltage-Gated Calcium Channel Auxiliary α 2δ Subunits, and Enables Calcium Current Enhancement. FUNCTION 2022; 3:zqac013. [PMID: 35462614 PMCID: PMC9016415 DOI: 10.1093/function/zqac013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 03/09/2022] [Accepted: 03/10/2022] [Indexed: 01/07/2023] Open
Abstract
The auxiliary α2δ subunits of voltage-gated calcium (CaV) channels are key to augmenting expression and function of CaV1 and CaV2 channels, and are also important drug targets in several therapeutic areas, including neuropathic pain. The α2δ proteins are translated as preproteins encoding both α2 and δ, and post-translationally proteolyzed into α2 and δ subunits, which remain associated as a complex. In this study, we have identified ADAM17 as a key protease involved in proteolytic processing of pro-α2δ-1 and α2δ-3 subunits. We provide three lines of evidence: First, proteolytic cleavage is inhibited by chemical inhibitors of particular metalloproteases, including ADAM17. Second, proteolytic cleavage of both α2δ-1 and α2δ-3 is markedly reduced in cell lines by knockout of ADAM17 but not ADAM10. Third, proteolytic cleavage is reduced by the N-terminal active domain of TIMP-3 (N-TIMP-3), which selectively inhibits ADAM17. We have found previously that proteolytic cleavage into mature α2δ is essential for the enhancement of CaV function, and in agreement, knockout of ADAM17 inhibited the ability of α2δ-1 to enhance both CaV2.2 and CaV1.2 calcium currents. Finally, our data also indicate that the main site of proteolytic cleavage of α2δ-1 is the Golgi apparatus, although cleavage may also occur at the plasma membrane. Thus, our study identifies ADAM17 as a key protease required for proteolytic maturation of α2δ-1 and α2δ-3, and thus a potential drug target in neuropathic pain.
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Affiliation(s)
- Ivan Kadurin
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Shehrazade Dahimene
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Karen M Page
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Joseph I J Ellaway
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Kanchan Chaggar
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Linda Troeberg
- Norwich Medical School, University of East Anglia, Norwich NR4 7UQ, UK
| | - Hideaki Nagase
- Kennedy Institute of Rheumatology, University of Oxford, Oxford OX3 7FY, UK
| | - Annette C Dolphin
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
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9
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Le T, Martín-Aragón Baudel M, Syed A, Singhrao N, Pan S, Flores-Tamez VA, Burns AE, Man KNM, Karey E, Hong J, Hell JW, Pinkerton KE, Chen CY, Nieves-Cintrón M. Secondhand Smoke Exposure Impairs Ion Channel Function and Contractility of Mesenteric Arteries. FUNCTION 2021; 2:zqab041. [PMID: 34553140 PMCID: PMC8448673 DOI: 10.1093/function/zqab041] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 08/05/2021] [Accepted: 08/16/2021] [Indexed: 01/11/2023] Open
Abstract
Cigarette smoke, including secondhand smoke (SHS), has significant detrimental vascular effects, but its effects on myogenic tone of small resistance arteries and the underlying mechanisms are understudied. Although it is apparent that SHS contributes to endothelial dysfunction, much less is known about how this toxicant alters arterial myocyte contraction, leading to alterations in myogenic tone. The study's goal is to determine the effects of SHS on mesenteric arterial myocyte contractility and excitability. C57BL/6J male mice were randomly assigned to either filtered air (FA) or SHS (6 h/d, 5 d/wk) exposed groups for a 4, 8, or 12-weeks period. Third and fourth-order mesenteric arteries and arterial myocytes were acutely isolated and evaluated with pressure myography and patch clamp electrophysiology, respectively. Myogenic tone was found to be elevated in mesenteric arteries from mice exposed to SHS for 12 wk but not for 4 or 8 wk. These results were correlated with an increase in L-type Ca2+ channel activity in mesenteric arterial myocytes after 12 wk of SHS exposure. Moreover, 12 wk SHS exposed arterial myocytes have reduced total potassium channel current density, which correlates with a depolarized membrane potential (Vm). These results suggest that SHS exposure induces alterations in key ionic conductances that modulate arterial myocyte contractility and myogenic tone. Thus, chronic exposure to an environmentally relevant concentration of SHS impairs mesenteric arterial myocyte electrophysiology and myogenic tone, which may contribute to increased blood pressure and risks of developing vascular complications due to passive exposure to cigarette smoke.
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Affiliation(s)
- Thanhmai Le
- Department of Pharmacology, University of California Davis, Davis, CA 95616, USA
| | | | - Arsalan Syed
- Department of Pharmacology, University of California Davis, Davis, CA 95616, USA
| | - Navid Singhrao
- Department of Pharmacology, University of California Davis, Davis, CA 95616, USA
| | - Shiyue Pan
- Department of Pharmacology, University of California Davis, Davis, CA 95616, USA
| | | | - Abby E Burns
- Department of Pharmacology, University of California Davis, Davis, CA 95616, USA
| | - Kwun Nok Mimi Man
- Department of Pharmacology, University of California Davis, Davis, CA 95616, USA
| | - Emma Karey
- Department of Pharmacology, University of California Davis, Davis, CA 95616, USA
| | - Junyoung Hong
- Department of Pharmacology, University of California Davis, Davis, CA 95616, USA
| | - Johannes W Hell
- Department of Pharmacology, University of California Davis, Davis, CA 95616, USA
| | - Kent E Pinkerton
- Center for Health and the Environment, University of California, Davis, CA 95616, USA
| | - Chao-Yin Chen
- Department of Pharmacology, University of California Davis, Davis, CA 95616, USA
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10
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Turner M, Anderson DE, Bartels P, Nieves-Cintron M, Coleman AM, Henderson PB, Man KNM, Tseng PY, Yarov-Yarovoy V, Bers DM, Navedo MF, Horne MC, Ames JB, Hell JW. α-Actinin-1 promotes activity of the L-type Ca 2+ channel Ca v 1.2. EMBO J 2020; 39:e102622. [PMID: 31985069 DOI: 10.15252/embj.2019102622] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 12/04/2019] [Accepted: 12/06/2019] [Indexed: 01/05/2023] Open
Abstract
The L-type Ca2+ channel CaV 1.2 governs gene expression, cardiac contraction, and neuronal activity. Binding of α-actinin to the IQ motif of CaV 1.2 supports its surface localization and postsynaptic targeting in neurons. We report a bi-functional mechanism that restricts CaV 1.2 activity to its target sites. We solved separate NMR structures of the IQ motif (residues 1,646-1,664) bound to α-actinin-1 and to apo-calmodulin (apoCaM). The CaV 1.2 K1647A and Y1649A mutations, which impair α-actinin-1 but not apoCaM binding, but not the F1658A and K1662E mutations, which impair apoCaM but not α-actinin-1 binding, decreased single-channel open probability, gating charge movement, and its coupling to channel opening. Thus, α-actinin recruits CaV 1.2 to defined surface regions and simultaneously boosts its open probability so that CaV 1.2 is mostly active when appropriately localized.
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Affiliation(s)
- Matthew Turner
- Department of Chemistry, University of California, Davis, CA, USA
| | - David E Anderson
- Department of Chemistry, University of California, Davis, CA, USA
| | - Peter Bartels
- Department of Pharmacology, University of California, Davis, CA, USA
| | | | - Andrea M Coleman
- Department of Chemistry, University of California, Davis, CA, USA.,Department of Pharmacology, University of California, Davis, CA, USA
| | - Peter B Henderson
- Department of Pharmacology, University of California, Davis, CA, USA
| | - Kwun Nok Mimi Man
- Department of Pharmacology, University of California, Davis, CA, USA
| | - Pang-Yen Tseng
- Department of Pharmacology, University of California, Davis, CA, USA
| | | | - Donald M Bers
- Department of Pharmacology, University of California, Davis, CA, USA
| | - Manuel F Navedo
- Department of Pharmacology, University of California, Davis, CA, USA
| | - Mary C Horne
- Department of Pharmacology, University of California, Davis, CA, USA
| | - James B Ames
- Department of Chemistry, University of California, Davis, CA, USA
| | - Johannes W Hell
- Department of Pharmacology, University of California, Davis, CA, USA
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11
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Syed AU, Reddy GR, Ghosh D, Prada MP, Nystoriak MA, Morotti S, Grandi E, Sirish P, Chiamvimonvat N, Hell JW, Santana LF, Xiang YK, Nieves-Cintrón M, Navedo MF. Adenylyl cyclase 5-generated cAMP controls cerebral vascular reactivity during diabetic hyperglycemia. J Clin Invest 2019; 129:3140-3152. [PMID: 31162142 PMCID: PMC6668679 DOI: 10.1172/jci124705] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 05/14/2019] [Indexed: 12/20/2022] Open
Abstract
Elevated blood glucose (hyperglycemia) is a hallmark metabolic abnormality in diabetes. Hyperglycemia is associated with protein kinase A (PKA)-mediated stimulation of L-type Ca2+ channels in arterial myocytes resulting in increased vasoconstriction. However, the mechanisms by which glucose activates PKA remain unclear. Here, we showed that elevating extracellular glucose stimulates cAMP production in arterial myocytes, and that this was specifically dependent on adenylyl cyclase 5 (AC5) activity. Super-resolution imaging suggested nanometer proximity between subpopulations of AC5 and the L-type Ca2+ channel pore-forming subunit CaV1.2. In vitro, in silico, ex vivo and in vivo experiments revealed that this close association is critical for stimulation of L-type Ca2+ channels in arterial myocytes and increased myogenic tone upon acute hyperglycemia. This pathway supported the increase in L-type Ca2+ channel activity and myogenic tone in two animal models of diabetes. Our collective findings demonstrate a unique role for AC5 in PKA-dependent modulation of L-type Ca2+ channel activity and vascular reactivity during acute hyperglycemia and diabetes.
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MESH Headings
- Adenylyl Cyclases/genetics
- Adenylyl Cyclases/metabolism
- Animals
- Calcium Channels, L-Type/biosynthesis
- Calcium Channels, L-Type/genetics
- Cerebral Arteries/enzymology
- Cerebral Arteries/pathology
- Cyclic AMP/genetics
- Cyclic AMP/metabolism
- Cyclic AMP-Dependent Protein Kinases/genetics
- Cyclic AMP-Dependent Protein Kinases/metabolism
- Diabetes Mellitus, Experimental/enzymology
- Diabetes Mellitus, Experimental/genetics
- Diabetes Mellitus, Experimental/pathology
- Hyperglycemia/enzymology
- Hyperglycemia/genetics
- Hyperglycemia/pathology
- Mice
- Mice, Knockout
- Muscle, Smooth, Vascular/enzymology
- Muscle, Smooth, Vascular/pathology
- Myocytes, Smooth Muscle/enzymology
- Myocytes, Smooth Muscle/pathology
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Affiliation(s)
- Arsalan U. Syed
- Department of Pharmacology, University of California, Davis, Davis, California, USA
| | - Gopireddy R. Reddy
- Department of Pharmacology, University of California, Davis, Davis, California, USA
| | - Debapriya Ghosh
- Department of Pharmacology, University of California, Davis, Davis, California, USA
| | - Maria Paz Prada
- Department of Pharmacology, University of California, Davis, Davis, California, USA
| | - Matthew A. Nystoriak
- Diabetes and Obesity Center, Department of Medicine, University of Louisville, Louisville, Kentucky, USA
| | - Stefano Morotti
- Department of Pharmacology, University of California, Davis, Davis, California, USA
| | - Eleonora Grandi
- Department of Pharmacology, University of California, Davis, Davis, California, USA
| | - Padmini Sirish
- Department of Internal Medicine, University of California, Davis, Davis, California, USA
| | - Nipavan Chiamvimonvat
- Department of Pharmacology, University of California, Davis, Davis, California, USA
- Department of Internal Medicine, University of California, Davis, Davis, California, USA
- VA Northern California Health Care System, Mather, California, USA
| | - Johannes W. Hell
- Department of Pharmacology, University of California, Davis, Davis, California, USA
| | - Luis F. Santana
- Department of Physiology and Membrane Biology, University of California, Davis, Davis, California, USA
| | - Yang K. Xiang
- Department of Pharmacology, University of California, Davis, Davis, California, USA
- VA Northern California Health Care System, Mather, California, USA
| | | | - Manuel F. Navedo
- Department of Pharmacology, University of California, Davis, Davis, California, USA
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12
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Ito DW, Hannigan KI, Ghosh D, Xu B, Del Villar SG, Xiang YK, Dickson EJ, Navedo MF, Dixon RE. β-adrenergic-mediated dynamic augmentation of sarcolemmal Ca V 1.2 clustering and co-operativity in ventricular myocytes. J Physiol 2019; 597:2139-2162. [PMID: 30714156 PMCID: PMC6462464 DOI: 10.1113/jp277283] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Accepted: 02/03/2019] [Indexed: 01/25/2023] Open
Abstract
Key points Prevailing dogma holds that activation of the β‐adrenergic receptor/cAMP/protein kinase A signalling pathway leads to enhanced L‐type CaV1.2 channel activity, resulting in increased Ca2+ influx into ventricular myocytes and a positive inotropic response. However, the full mechanistic and molecular details underlying this phenomenon are incompletely understood. CaV1.2 channel clusters decorate T‐tubule sarcolemmas of ventricular myocytes. Within clusters, nanometer proximity between channels permits Ca2+‐dependent co‐operative gating behaviour mediated by physical interactions between adjacent channel C‐terminal tails. We report that stimulation of cardiomyocytes with isoproterenol, evokes dynamic, protein kinase A‐dependent augmentation of CaV1.2 channel abundance along cardiomyocyte T‐tubules, resulting in the appearance of channel ‘super‐clusters’, and enhanced channel co‐operativity that amplifies Ca2+ influx. On the basis of these data, we suggest a new model in which a sub‐sarcolemmal pool of pre‐synthesized CaV1.2 channels resides in cardiomyocytes and can be mobilized to the membrane in times of high haemodynamic or metabolic demand, to tune excitation–contraction coupling.
Abstract Voltage‐dependent L‐type CaV1.2 channels play an indispensable role in cardiac excitation–contraction coupling. Activation of the β‐adrenergic receptor (βAR)/cAMP/protein kinase A (PKA) signalling pathway leads to enhanced CaV1.2 activity, resulting in increased Ca2+ influx into ventricular myocytes and a positive inotropic response. CaV1.2 channels exhibit a clustered distribution along the T‐tubule sarcolemma of ventricular myocytes where nanometer proximity between channels permits Ca2+‐dependent co‐operative gating behaviour mediated by dynamic, physical, allosteric interactions between adjacent channel C‐terminal tails. This amplifies Ca2+ influx and augments myocyte Ca2+ transient and contraction amplitudes. We investigated whether βAR signalling could alter CaV1.2 channel clustering to facilitate co‐operative channel interactions and elevate Ca2+ influx in ventricular myocytes. Bimolecular fluorescence complementation experiments reveal that the βAR agonist, isoproterenol (ISO), promotes enhanced CaV1.2–CaV1.2 physical interactions. Super‐resolution nanoscopy and dynamic channel tracking indicate that these interactions are expedited by enhanced spatial proximity between channels, resulting in the appearance of CaV1.2 ‘super‐clusters’ along the z‐lines of ISO‐stimulated cardiomyocytes. The mechanism that leads to super‐cluster formation involves rapid, dynamic augmentation of sarcolemmal CaV1.2 channel abundance after ISO application. Optical and electrophysiological single channel recordings confirm that these newly inserted channels are functional and contribute to overt co‐operative gating behaviour of CaV1.2 channels in ISO stimulated myocytes. The results of the present study reveal a new facet of βAR‐mediated regulation of CaV1.2 channels in the heart and support the novel concept that a pre‐synthesized pool of sub‐sarcolemmal CaV1.2 channel‐containing vesicles/endosomes resides in cardiomyocytes and can be mobilized to the sarcolemma to tune excitation–contraction coupling to meet metabolic and/or haemodynamic demands. Prevailing dogma holds that activation of the β‐adrenergic receptor/cAMP/protein kinase A signalling pathway leads to enhanced L‐type CaV1.2 channel activity, resulting in increased Ca2+ influx into ventricular myocytes and a positive inotropic response. However, the full mechanistic and molecular details underlying this phenomenon are incompletely understood. CaV1.2 channel clusters decorate T‐tubule sarcolemmas of ventricular myocytes. Within clusters, nanometer proximity between channels permits Ca2+‐dependent co‐operative gating behaviour mediated by physical interactions between adjacent channel C‐terminal tails. We report that stimulation of cardiomyocytes with isoproterenol, evokes dynamic, protein kinase A‐dependent augmentation of CaV1.2 channel abundance along cardiomyocyte T‐tubules, resulting in the appearance of channel ‘super‐clusters’, and enhanced channel co‐operativity that amplifies Ca2+ influx. On the basis of these data, we suggest a new model in which a sub‐sarcolemmal pool of pre‐synthesized CaV1.2 channels resides in cardiomyocytes and can be mobilized to the membrane in times of high haemodynamic or metabolic demand, to tune excitation–contraction coupling.
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Affiliation(s)
- Danica W Ito
- Department of Physiology & Membrane Biology, University of California Davis, Davis, CA, USA
| | - Karen I Hannigan
- Department of Physiology & Membrane Biology, University of California Davis, Davis, CA, USA
| | - Debapriya Ghosh
- Department of Pharmacology, University of California Davis, Davis, CA, USA
| | - Bing Xu
- Department of Pharmacology, University of California Davis, Davis, CA, USA
| | - Silvia G Del Villar
- Department of Physiology & Membrane Biology, University of California Davis, Davis, CA, USA
| | - Yang K Xiang
- Department of Pharmacology, University of California Davis, Davis, CA, USA.,VA Northern California Health Care System, Mather, CA, USA
| | - Eamonn J Dickson
- Department of Physiology & Membrane Biology, University of California Davis, Davis, CA, USA
| | - Manuel F Navedo
- Department of Pharmacology, University of California Davis, Davis, CA, USA
| | - Rose E Dixon
- Department of Physiology & Membrane Biology, University of California Davis, Davis, CA, USA
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13
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Prada MP, Syed AU, Buonarati OR, Reddy GR, Nystoriak MA, Ghosh D, Simó S, Sato D, Sasse KC, Ward SM, Santana LF, Xiang YK, Hell JW, Nieves-Cintrón M, Navedo MF. A G s-coupled purinergic receptor boosts Ca 2+ influx and vascular contractility during diabetic hyperglycemia. eLife 2019; 8:42214. [PMID: 30821687 PMCID: PMC6397001 DOI: 10.7554/elife.42214] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Accepted: 02/16/2019] [Indexed: 12/21/2022] Open
Abstract
Elevated glucose increases vascular reactivity by promoting L-type CaV1.2 channel (LTCC) activity by protein kinase A (PKA). Yet, how glucose activates PKA is unknown. We hypothesized that a Gs-coupled P2Y receptor is an upstream activator of PKA mediating LTCC potentiation during diabetic hyperglycemia. Experiments in apyrase-treated cells suggested involvement of a P2Y receptor underlying the glucose effects on LTTCs. Using human tissue, expression for P2Y11, the only Gs-coupled P2Y receptor, was detected in nanometer proximity to CaV1.2 and PKA. FRET-based experiments revealed that the selective P2Y11 agonist NF546 and elevated glucose stimulate cAMP production resulting in enhanced PKA-dependent LTCC activity. These changes were blocked by the selective P2Y11 inhibitor NF340. Comparable results were observed in mouse tissue, suggesting that a P2Y11-like receptor is mediating the glucose response in these cells. These findings established a key role for P2Y11 in regulating PKA-dependent LTCC function and vascular reactivity during diabetic hyperglycemia.
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Affiliation(s)
- Maria Paz Prada
- Department of Pharmacology, University of California, Davis, Davis, United States
| | - Arsalan U Syed
- Department of Pharmacology, University of California, Davis, Davis, United States
| | - Olivia R Buonarati
- Department of Pharmacology, University of California, Davis, Davis, United States
| | - Gopireddy R Reddy
- Department of Pharmacology, University of California, Davis, Davis, United States
| | - Matthew A Nystoriak
- Diabetes & Obesity Center, Department of Medicine, University of Louisville, Kentucky, United States
| | - Debapriya Ghosh
- Department of Pharmacology, University of California, Davis, Davis, United States
| | - Sergi Simó
- Department of Cell Biology & Human Anatomy, University of California, Davis, Davis, United States
| | - Daisuke Sato
- Department of Pharmacology, University of California, Davis, Davis, United States
| | | | - Sean M Ward
- Department of Physiology & Cell Biology, University of Nevada, Reno, United States
| | - Luis F Santana
- Department of Physiology & Membrane Biology, University of California, Davis, Davis, United States
| | - Yang K Xiang
- Department of Pharmacology, University of California, Davis, Davis, United States.,VA Northern California Healthcare System, Mather, United States
| | - Johannes W Hell
- Department of Pharmacology, University of California, Davis, Davis, United States
| | | | - Manuel F Navedo
- Department of Pharmacology, University of California, Davis, Davis, United States
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14
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Temme SJ, Murphy GG. The L-type voltage-gated calcium channel Ca V1.2 mediates fear extinction and modulates synaptic tone in the lateral amygdala. ACTA ACUST UNITED AC 2017; 24:580-588. [PMID: 29038219 PMCID: PMC5647931 DOI: 10.1101/lm.045773.117] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 07/17/2017] [Indexed: 12/15/2022]
Abstract
L-type voltage-gated calcium channels (LVGCCs) have been implicated in both the formation and the reduction of fear through Pavlovian fear conditioning and extinction. Despite the implication of LVGCCs in fear learning and extinction, studies of the individual LVGCC subtypes, CaV1.2 and CaV1.3, using transgenic mice have failed to find a role of either subtype in fear extinction. This discontinuity between the pharmacological studies of LVGCCs and the studies investigating individual subtype contributions could be due to the limited neuronal deletion pattern of the CaV1.2 conditional knockout mice previously studied to excitatory neurons in the forebrain. To investigate the effects of deletion of CaV1.2 in all neuronal populations, we generated CaV1.2 conditional knockout mice using the synapsin1 promoter to drive Cre recombinase expression. Pan-neuronal deletion of CaV1.2 did not alter basal anxiety or fear learning. However, pan-neuronal deletion of CaV1.2 resulted in a significant deficit in extinction of contextual fear, implicating LVGCCs, specifically CaV1.2, in extinction learning. Further exploration on the effects of deletion of CaV1.2 on inhibitory and excitatory input onto the principle neurons of the lateral amygdala revealed a significant shift in inhibitory/excitatory balance. Together these data illustrate an important role of CaV1.2 in fear extinction and the synaptic regulation of activity within the amygdala.
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Affiliation(s)
- Stephanie J Temme
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, Michigan 48109-2200, USA
| | - Geoffrey G Murphy
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, Michigan 48109-2200, USA.,Molecular and Behavioral Neuroscience Institute, University of Michigan, Ann Arbor, Michigan 48109-2200, USA.,Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan 48109-2200, USA
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