DOCSLIB.ORG

Translocatable Voltage-Gated Ca2+ Channel Β Subunits in Α1–Β

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Translocatable Voltage-Gated Ca2+ Channel Β Subunits in Α1–Β + Translocatable voltage-gated Ca2 channel β subunits in α1–β complexes reveal competitive replacement yet no spontaneous dissociation Jun-Hee Yeona, Cheon-Gyu Parka, Bertil Hilleb,1, and Byung-Chang Suha,1 aDepartment of Brain & Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, 42988 Daegu, South Korea; and bDepartment of Physiology and Biophysics, University of Washington, Seattle, WA 98195 Contributed by Bertil Hille, August 28, 2018 (sent for review June 8, 2018; reviewed by Diane Lipscombe and Daniel L. Minor Jr.) 2+ K β β subunits of high voltage-gated Ca (CaV) channels promote cell- affinity ( d) of 5 to 20 nM depending on the subunit isoform surface expression of pore-forming α1 subunits and regulate chan- and experimental conditions (15–23). In intact cells, the stability nel gating through binding to the α-interaction domain (AID) in of the channel CaV α1–β complex is not well understood, but that the first intracellular loop. We addressed the stability of CaV α1B–β interaction is said to have lower apparent affinity and to be more interactions by rapamycin-translocatable Ca β subunits that allow dynamic than in vitro. For instance, injection of purified β2a V Xenopus drug-induced sequestration and uncoupling of the β subunit from protein into oocytes expressing CaV2.3 precoupled with Ca 2.2 channel complexes in intact cells. Without Ca α1B/α2δ1, all β1b subunits changed the fast inactivating currents to slowly V V K modified β subunits, except membrane-tethered β2a and β2e, are in inactivating currents over several hours (24). The apparent d –β the cytosol and rapidly translocate upon rapamycin addition to an- for the CaV2.3 1b interaction is reported to rise to several chors on target organelles: plasma membrane, mitochondria, or endo- hundred nanomolar inside cells, allowing dynamic exchange of α α δ the β subunit on α1E subunits and competition in the binding of plasmic reticulum. In cells coexpressing CaV 1B/ 2 1subunits,the β α translocatable β subunits colocalize at the plasma membrane with two different isoforms for one 1 subunit (25). The apparent α α1–β binding affinity depends on the molecular properties of β 1B and stay there after rapamycin application, indicating that inter- α –β α – actions between α1B and bound β subunits are very stable. However, isoforms; thus, the 1C 1a complex is more stable than 1C β α –β NEUROSCIENCE the interaction becomes dynamic when other competing β isoforms 2a or 1C 4 in intact skeletal muscle cells (26). Similarly, in- tracellular perfusion of degradation-protected AID peptides are coexpressed. Addition of rapamycin, then, switches channel gating blocked the interaction of CaV1.2 channels with β3 subunits, but and regulation by phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2] not with β2a, indicating that the CaV1.2–β3 complex is less stable lipid. Thus, expression of free β isoforms around the channel reveals –β α –β than the CaV1.2 2a complex inside cells (27). In contrast, in a dynamic aspect to the 1B interaction. On the other hand, excised inside-out patches, the β2a subunit remains stably bound translocatable β subunits with AID-binding site mutations are eas- to the core domains of CaV2.1 channels unless the binding af- ily dissociated from CaV α1B on the addition of rapamycin, decreas- finity of CaV β GK domain is reduced by mutating the α-binding ing current amplitude and PI(4,5)P2 sensitivity. Furthermore, the pocket (ABP) site (28). Thus, in vitro work has emphasized high mutations slow CaV2.2 current inactivation and shift the voltage stability of CaV–β complexes whereas intact-cell work has em- dependence of activation to more positive potentials. Mutated phasized dynamic exchange of β subunits. β translocatable subunits work similarly in CaV2.3 channels. In sum, Here, we developed chimeric translocatable Ca β subunits. They α –β V the strong interaction of CaV 1B subunits can be overcome by can be translocated rapidly by chemically inducible heterodimerization other free β isoforms, permitting dynamic changes in channel prop- erties in intact cells. Significance 2+ β voltage-gated Ca channel | CaV subunits | chemically inducible 2+ Voltage-gated Ca (CaV) channels have an α1-α2δ core com- dimerization | rapamycin | PI(4,5)P2 plexed with one of several alternative β subunits. Contradictory i β 2+ evidence says that, once bound, ( )a subunit is permanently oltage-gated Ca (CaV) channels play essential roles con- α α δ ii 2+ associated with the 1- 2 core or ( )thatitisfreetobe Vverting electrical signals to changes in Ca -dependent pro- exchanged for other β subunits. We designed rapamycin- cesses like synaptic transmission, muscle contraction, and gene translocatable CaV β subunits that allow drug-induced seques- transcription (1). The CaV channels can be divided into high voltage- tration of free β subunits to several organelle anchors. Seques- activated (HVA) (CaV1andCaV2) and low voltage-activated (LVA) tering free subunits does not dissociate bound subunits from (CaV3) channels in accordance with their activation threshold. HVA channels except when the binding site is mutated to weaken the 2+ α Ca channels are composed of a pore-forming 1 subunit and at interaction. Nevertheless, our rapamycin constructs show that, α least three auxiliary subunits, the disulfide-linked complex of 2and when nontranslocatable β subunits are coexpressed with a δ plus β. The auxiliary β subunit regulates cell surface trafficking and translocatable subunit, sequestering the translocatable subunit 2+ biophysical gating properties of HVA Ca channels via an in- changes the channel properties, revealing a quick replacement α – teraction with the CaV 1 subunit in 1:1 stoichiometry (2 4). Four by the nontranslocatable subunit in the channel complex. distinct genes encode β1-β4 subunits and their splice variants (5–7). The β subunits contain a highly variable N and C terminus and a Author contributions: J.-H.Y., C.-G.P., B.H., and B.-C.S. designed research; J.-H.Y. and HOOK domain separating highly conserved src homology-3 (SH3) C.-G.P. performed research; J.-H.Y., C.-G.P., and B.-C.S. analyzed data; and J.-H.Y., B.H., and guanylate kinase (GK) domains. The GK domain contains the and B.-C.S. wrote the paper. α-binding pocket (ABP) that interacts directly with the α-interaction Reviewers: D.L., Brown University; and D.L.M., University of California, San Francisco. The authors declare no conflict of interest. domain (AID) of the cytosolic I-II loop of CaV α1 subunits (8–11). An additional lower affinity binding site in the C terminus of β Published under the PNAS license. subunits contributes to the interaction with the C terminus of α1and 1To whom correspondence may be addressed. Email: [email protected] or [email protected]. to regulation of channel-gating properties (12–14). This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10. Studies with in vitro assays report that the interaction between 1073/pnas.1809762115/-/DCSupplemental. the AID of CaV α1 and CaV β subunits is strong, with a binding www.pnas.org/cgi/doi/10.1073/pnas.1809762115 PNAS Latest Articles | 1of10 Downloaded by guest on September 26, 2021 to a membrane anchor on an intracellular organelle, including CaV β GK domain (28). We show that acute dissociation of β the plasma membrane, mitochondria, and endoplasmic reticu- subunits from CaV α1B dramatically changes the functional lum (ER), upon addition of rapamycin. Using this method, rapid properties of CaV2.2 channels. sequestration of free β subunits helped us to analyze the stability of CaV α1–β complexes in intact cells and the roles of β subunits Results in channel gating. The heterodimerization is based on formation Generation and Characterization of Translocatable CaV β Subunits. of a ternary complex between recombinant FK506 binding pro- CaV β subunits are noncovalently coupled to membrane-resident tein (FKBP) and FKBP-rapamycin binding (FRB) protein upon CaV α1 subunits of living cells (32). To further understand the addition of rapamycin (29–31). In our experiments, chimeric β interaction properties, we used rapamycin-induced translocation subunit-FKBP proteins were heterodimerized through rapamy- of β subunits. CaV β isoforms were labeled at the C terminus with cin with an FRB anchor on a target organelle. The designed recombinant FKBP and then in tandem with green (or mCherry) translocatable CaV β systems permit study of association or dis- fluorescent protein; this produced the final β-FKBP-GFP (β-FG) sociation of β subunits from CaV α1B channels located in the proteins that can be recruited to specific subcellular target or- plasma membrane in living cells. We provide evidence that the ganelles by rapamycin (Fig. 1A and SI Appendix,Fig.S1). The interaction of CaV α1 with β subunits can be very stable inside target organelles were labeled with FRB and mCherry-fluorescent cells. The complex does not dissociate up to several hours. protein fused to organelle membrane-specific marker proteins: However, if there are other types of free β isoforms around the Lyn11 for the plasma membrane (LDR), Tom20 for mitochondrial channels, there can be exchange with the coupled β subunits on outer membranes (Tom20-MR), and Cb5 for the ER (MR-Cb5). the α1B protein. The CaV α1–β interaction can be weakened by FKBP and FRB construct pairs allowed rapid sequestration of mutating two residues in the α-binding pocket (ABP) site of the recombinant β-FG protein to specific organelles via the formation Fig. 1. Subcellular translocation of CaV β subunits on the addition of rapamycin in intact tsA-201 cells. (A) Schematic diagram of translocatable β subunit (β-FG) and target organelle anchors.
Load more

Recommended publications
  • CURRICULUM VITAE December, 2018 DIANE LIPSCOMBE, Phd
    CURRICULUM VITAE December, 2018 DIANE LIPSCOMBE, PhD Brown University Brown Institute for Brain Science 2 Stimson Avenue Providence, RI 02912 [email protected] EDUCATION 1982 B.Sc. (Hons) 1982: University College London, Department of Pharmacology. 1986 Ph.D. University College London, Department of Pharmacology. Thesis title: “Pharmacology of nicotinic receptors on frog neurones: Electrophysiological studies on intact and dissociated ganglia”. APPOINTMENTS 1978-1982 Technician, the Welcome Research Laboratories, Beckenham, Kent, England. Supervised by Sir James W. Black. Full-time:1978 -1979; summers: 1980-1982. 1982-1986 Graduate Student at University College London, Department of Pharmacology. Supervised by Humphrey P. Rang (FRS) and David Colquhoun (FRS). 1986-1988 Postdoctoral Associate at Yale University School of Medicine, Department of Cellular and Molecular Physiology in the laboratory of Richard W. Tsien. 1989-1990 Postdoctoral Fellow at Stanford Medical School, Department of Molecular and Cellular Physiology in the laboratory of Richard W. Tsien. 1990-1992 Visiting Assistant Professor and consultant, Miles Pharmaceuticals, West Haven, CT. 1990-1993 Assistant Professor of Physiology (Research), Brown University, Division of Biology and Medicine. 1993-1999 Assistant Professor of Neuroscience (Tenure Track), Brown University, Division of Biology and Medicine. 1997 Visiting Assistant Professor in the Centers for Genome Research and for Neuroscience, Edinburgh University, UK. 1999 Associate Professor of Neuroscience (with tenure), Brown University. 2006 Professor of Neuroscience, Brown University. 2014-2015 Co-Director, Center for Neurobiology of Cells and Circuits, Brown Institute for Brain Science. 2015-2016 Interim Director, Brown Institute for Brain Science. 2016 Adjunct Professor of George and Anne Ryan Institute for Neuroscience, University of Rhode Island.
    [Show full text]
  • Cell-Specific Exon Methylation and CTCF Binding in Neurons Regulate Calcium Ion Channel Splicing and Function Eduardo Javier Lo´ Pez Soto, Diane Lipscombe*
    RESEARCH ARTICLE Cell-specific exon methylation and CTCF binding in neurons regulate calcium ion channel splicing and function Eduardo Javier Lo´ pez Soto, Diane Lipscombe* The Robert J and Nancy D Carney Institute for Brain Science & Department of Neuroscience, Brown University, Providence, United States Abstract Cell-specific alternative splicing modulates myriad cell functions and is disrupted in disease. The mechanisms governing alternative splicing are known for relatively few genes and typically focus on RNA splicing factors. In sensory neurons, cell-specific alternative splicing of the Cacna1b presynaptic CaV channel gene modulates opioid sensitivity. How this splicing is regulated is unknown. We find that cell and exon-specific DNA hypomethylation permits CTCF binding, the master regulator of mammalian chromatin structure, which, in turn, controls splicing in a DRG- derived cell line. In vivo, hypomethylation of an alternative exon specifically in nociceptors, likely permits CTCF binding and expression of CaV2.2 channel isoforms with increased opioid sensitivity in mice. Following nerve injury, exon methylation is increased, and splicing is disrupted. Our studies define the molecular mechanisms of cell-specific alternative splicing of a functionally validated exon in normal and disease states – and reveal a potential target for the treatment of chronic pain. Introduction The precise exon composition of expressed genes defines fundamental features of neuronal function (Fiszbein and Kornblihtt, 2017; Lopez Soto et al., 2019; Ule and Blencowe, 2019). It is essential *For correspondence: [email protected] to understand the mechanisms that regulate alternative pre mRNA splicing. This dynamic process regulates exon composition for >95% of multi-exon genes according to cell-type and influenced by Competing interests: The development, cellular activity and disease (Furlanis and Scheiffele, 2018).
    [Show full text]
  • EVALUATING the ROLE of a Cav2.2 SPLICE VARIANT in BEHAVIORAL RESPONSES to STRESS, NOVELTY, and OTHER MONOAMINE-LINKED FUNCTIONS
    University of New Hampshire University of New Hampshire Scholars' Repository Master's Theses and Capstones Student Scholarship Winter 2019 EVALUATING THE ROLE OF A CaV2.2 SPLICE VARIANT IN BEHAVIORAL RESPONSES TO STRESS, NOVELTY, AND OTHER MONOAMINE-LINKED FUNCTIONS Ashton Brennecke University of New Hampshire, Durham Follow this and additional works at: https://scholars.unh.edu/thesis Recommended Citation Brennecke, Ashton, "EVALUATING THE ROLE OF A CaV2.2 SPLICE VARIANT IN BEHAVIORAL RESPONSES TO STRESS, NOVELTY, AND OTHER MONOAMINE-LINKED FUNCTIONS" (2019). Master's Theses and Capstones. 1319. https://scholars.unh.edu/thesis/1319 This Thesis is brought to you for free and open access by the Student Scholarship at University of New Hampshire Scholars' Repository. It has been accepted for inclusion in Master's Theses and Capstones by an authorized administrator of University of New Hampshire Scholars' Repository. For more information, please contact [email protected]. EVALUATING THE ROLE OF A CaV2.2 SPLICE VARIANT IN BEHAVIORAL RESPONSES TO STRESS, NOVELTY, AND OTHER MONOAMINE-LINKED FUNCTIONS BY ASHTON BRENNECKE BS Biology, Asbury University, 2017 THESIS Submitted to the University of New Hampshire in Partial Fulfillment of the Requirements for the Degree of Master of Science in Genetics December, 2019 i This thesis/dissertation has been examined and approved in partial fulfillment of the requirements for the degree of Master of Science in Genetics by: Thesis Director, Arturo Andrade, Assistant Professor of Biological Sciences Xuanmao Chen, Assistant Professor of Molecular, Cellular, and Biomedical Sciences Sergios Charntikov, Assistant Professor of Psychology On November 8th, 2019 Original approval signatures are on file with the University of New Hampshire Graduate School.
    [Show full text]
  • Translocatable Voltage-Gated Ca2+ Channel Β Subunits in Α1–Β
    + Translocatable voltage-gated Ca2 channel β subunits in α1–β complexes reveal competitive replacement yet no spontaneous dissociation Jun-Hee Yeona, Cheon-Gyu Parka, Bertil Hilleb,1, and Byung-Chang Suha,1 aDepartment of Brain & Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, 42988 Daegu, South Korea; and bDepartment of Physiology and Biophysics, University of Washington, Seattle, WA 98195 Contributed by Bertil Hille, August 28, 2018 (sent for review June 8, 2018; reviewed by Diane Lipscombe and Daniel L. Minor Jr.) 2+ K β β subunits of high voltage-gated Ca (CaV) channels promote cell- affinity ( d) of 5 to 20 nM depending on the subunit isoform surface expression of pore-forming α1 subunits and regulate chan- and experimental conditions (15–23). In intact cells, the stability nel gating through binding to the α-interaction domain (AID) in of the channel CaV α1–β complex is not well understood, but that the first intracellular loop. We addressed the stability of CaV α1B–β interaction is said to have lower apparent affinity and to be more interactions by rapamycin-translocatable Ca β subunits that allow dynamic than in vitro. For instance, injection of purified β2a V Xenopus drug-induced sequestration and uncoupling of the β subunit from protein into oocytes expressing CaV2.3 precoupled with Ca 2.2 channel complexes in intact cells. Without Ca α1B/α2δ1, all β1b subunits changed the fast inactivating currents to slowly V V K modified β subunits, except membrane-tethered β2a and β2e, are in inactivating currents over several hours (24). The apparent d –β the cytosol and rapidly translocate upon rapamycin addition to an- for the CaV2.3 1b interaction is reported to rise to several chors on target organelles: plasma membrane, mitochondria, or endo- hundred nanomolar inside cells, allowing dynamic exchange of the β subunit on α1E subunits and competition in the binding of plasmic reticulum.
    [Show full text]
  • Alternative Splicing Controls G Protein Inhibition of Cav2.2 Calcium
    Alternative Splicing Controls G Protein Inhibition of CaV2.2 Calcium Channels Cecilia Goldsmith Phillips BA, Reed College, 2003 THESIS Submitted in partial fulfillment of the requirements for the Degree of Doctor of Philosophy in the Department of Neuroscience at Brown University Providence, Rhode Island May 2012 © 2012 Cecilia Goldsmith Phillips This dissertation by Cecilia Goldsmith Phillips is accepted in its present form by the Department of Neuroscience as satisfying the dissertation requirement for the degree of Doctor of Philosophy. Date Dr. Diane Lipscombe, Advisor Recommended to the Graduate Council Date Dr. Gilad Barnea, Reader Date Dr. Julie Kauer, Reader Date Dr. Stephen Ikeda, Outside Reader Approved by the Graduate Council Date Dr. Peter M. Weber, Dean of the Graduate School iii CURRICULUM VITAE 23 Elton St, Providence, RI 02906 (503) 705-7387 [email protected] EDUCATION Brown University, Providence, RI PhD, Neuroscience, May 2012 Reed College, Portland, OR BA, Biology, May 2003 Senior Thesis: Processing of GFP-tagged ELH Prohormone in PC12 Cells Advisor: Dr. Stephen Arch RESEARCH POSITIONS Research Assistant to Dr. Stephen M Smith, Division of Molecular Medicine, Oregon Health Sciences University, Portland, OR. September 2003 – August 2005 Internship with Dr. Peter Gillespie, Vollum Institute, Oregon Health Sciences University, Portland, OR. June 2003 – August 2003 Research Assistant to Dr. Maryanne McClellan, Department of Biology, Reed College, Portland, OR. June 2002 – August 2002 Research Assistant to Dr. David McKinnon, Department of Neuroscience, SUNY Stony Brook. June 2001 – August 2001 and June 2000 – August 2000 PUBLICATIONS Allen SE*, Phillips CG*, Raingo J, and D Lipscombe. The neuronal splicing factor Fox- 2 controls Gs protein inhibition of CaV2.2 calcium channels.
    [Show full text]
  • Cell Calcium the 2 Subunit Augments Functional Expression and Modifies
    Cell Calcium 46 (2009) 282–292 Contents lists available at ScienceDirect Cell Calcium journal homepage: www.elsevier.com/locate/ceca The ␣2␦ subunit augments functional expression and modifies the pharmacology of CaV1.3 L-type channels Arturo Andrade a,1, Alejandro Sandoval b,c, Ricardo González-Ramírez b, Diane Lipscombe d, Kevin P. Campbell e, Ricardo Felix b,∗ a Department of Physiology, Biophysics and Neuroscience, Center for Research and Advanced Studies of the National Polytechnic Institute, Cinvestav-IPN, Mexico City, Mexico b Department of Cell Biology, Cinvestav-IPN, Mexico City, Mexico c School of Medicine FES Iztacala, National Autonomous University of Mexico, Tlalnepantla, Mexico d Department of Neuroscience, Brown University, Providence, RI, USA e Howard Hughes Medical Institute and Department of Molecular Physiology and Biophysics, University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, IA, USA article info abstract 2+ Article history: The auxiliary CaV␣2␦-1 subunit is an important component of voltage-gated Ca (CaV) channel complexes Received 12 May 2009 in many tissues and of great interest as a drug target. Nevertheless, its exact role in specific cell functions Received in revised form 27 August 2009 is still unknown. This is particularly important in the case of the neuronal L-type CaV channels where Accepted 28 August 2009 these proteins play a key role in the secretion of neurotransmitters and hormones, gene expression, and Available online 30 September 2009 the activation of other ion channels. Therefore, using a combined approach of patch-clamp recordings and molecular biology, we studied the role of the CaV␣2␦-1 subunit on the functional expression and Keywords: the pharmacology of recombinant L-type Ca 1.3 channels in HEK-293 cells.
    [Show full text]
  • CACNA1B Mutation Is Linked to Unique Myoclonus Dystonia Syndrome
    UvA-DARE (Digital Academic Repository) Genetic architecture of dystonia Groen, J.L. Publication date 2014 Link to publication Citation for published version (APA): Groen, J. L. (2014). Genetic architecture of dystonia. General rights It is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulations If you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: https://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. UvA-DARE is a service provided by the library of the University of Amsterdam (https://dare.uva.nl) Download date:03 Oct 2021 2.1.B CACNA1B MUTATION IS LINKED TO UNIQUE MYOCLONUS DYSTONIA SYNDROME Justus L Groen*, Arturo Andrade*, Katja Ritz, Hamid Jalalzadeh, Martin Haagmans, Ted Bradley, Peter Nürnberg, Dineke Verbeek, Sylvia Denome, Raoul C.M. Hennekam, Diane Lipscombe, Frank Baas** & Marina A.J. Tijssen** * shared first;** shared last Submitted Groen.indd 57 11-2-2014 13:38:15 58 Chapter two ABSTRACT Exome sequencing combined with linkage analysis in a 3-generation pedigree with an unique familial Myoclonus-Dystonia syndrome (M-D) identified a mutation in the CACNA1B gene coding for the neuronal voltage-gated calcium channel CaV2.2.
    [Show full text]
  • Differential Ubiquitination and Proteasome Regulation of Cav 2.2 N-Type Channel Splice Isoforms
    The Journal of Neuroscience, July 25, 2012 • 32(30):10365–10369 • 10365 Cellular/Molecular Differential Ubiquitination and Proteasome Regulation of CaV2.2 N-Type Channel Splice Isoforms Spiro Marangoudakis, Arturo Andrade, Thomas D. Helton, Sylvia Denome, Andrew J. Castiglioni, and Diane Lipscombe Department of Neuroscience, Brown University, Providence, Rhode Island 02912 CaV2.2 (N-type) calcium channels control the entry of calcium into neurons to regulate essential functions but most notably presynaptic transmitter release. CaV2.2 channel expression levels are precisely controlled, but we know little of the cellular mechanisms involved. The ubiquitin proteasome system (UPS) is known to regulate expression of many synaptic proteins, including presynaptic elements, to optimize synaptic efficiency. However, we have limited information about ubiquitination of CaV2 channels. Here we show that CaV2.2 proteins are ubiquitinated, and that elements in the proximal C terminus of CaV2.2 encoded by exon 37b of the mouse Cacna1b gene predispose cloned and native channels to downregulation by the UPS. CaV2.2 channels containing e37b are expressed throughout the mammalian nervous system, but in some cells, notably nociceptors, sometimes e37a—not e37b—is selected during alternative splicing of CaV2.2 pre-mRNA. By a combination of biochemical and functional analyses we show e37b promotes a form of ubiquitination that is coupled to reduced CaV2.2 current density and increased sensitivity to the UPS. Cell-specific alternative splicing of e37a in nociceptors reduces CaV2.2 channel ubiquitination and sensitivity to the UPS, suggesting a role in pain processing. Introduction dependent changes in synaptic efficacy involve presynaptic com- ponents (Speese et al., 2003; Bingol and Schuman, 2005; Rinetti Presynaptic CaV2 channels mediate calcium entry to trigger neu- rotransmitter release and support synaptic transmission (Catter- and Schweizer, 2010), CaV2 channels were only recently recog- all, 2000).
    [Show full text]
  • Advances in Voltage-Gated Calcium Channel Structure, Function and Physiology
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector Biochimica et Biophysica Acta 1828 (2013) 1521 Contents lists available at SciVerse ScienceDirect Biochimica et Biophysica Acta journal homepage: www.elsevier.com/locate/bbamem Editorial Advances in voltage-gated calcium channel structure, function and physiology It is well established that calcium ions are important signalling molecular mechanisms of channel modulation. Dr. Henry Colecraft molecules that mediate a wide range of physiological functions, takes a broader view of high voltage activated calcium channel modula- including muscle contraction, enzyme activation, and secretion. Excitable tion by RGK proteins, a family of small G proteins that mediate a complex cells contain numerous pathways by which intracellular calcium concen- regulation of calcium channel activity. Finally, Dr. Daniela Pietrobon tration can be elevated. Voltage-gated calcium channels are the primary completes the issue by highlighting the role of Cav2.1 (P/Q-type) calcium mechanism of depolarization evoked calcium entry into heart, muscle channels in familial forms of migraine. In patients with this disorder and brain cells. The mammalian genome expresses multiple calcium naturally occurring mutations in the P/Q-type gene give rise to migraine channel subtypes that fulfill specific cellular functions. These calcium phenotypes with varying degrees of severity. channels can either be monomers (as is the case with low voltage- acti- Clearly, this collection of reviews is only a snapshot of the many vated T-type calcium channels), or multimeric protein complexes that exciting findings in the calcium channel field. However, it provides a are formed through the assembly of multiple calcium channels subunits topical overview of pertinent topics in this area by some of the world's (as for the high voltage-activated calcium channels).
    [Show full text]
  • A Dissertation Entitled Regulation of Neuronal L-Type Voltage-Gated
    A Dissertation entitled Regulation of Neuronal L-type Voltage-Gated Calcium Channels by Flurazepam and Other Positive Allosteric GABAA Receptor Modulators by Damien E. Earl Submitted to the Graduate Faculty as partial fulfillment of the requirements for the Doctor of Philosophy Degree in Biomedical Sciences ________________________________________ Dr. Elizabeth I. Tietz, Committee Chair ________________________________________ Dr. Zi-Jian Xie, Committee Member ________________________________________ Dr. David R. Giovannucci, Committee Member ________________________________________ Dr. Scott C. Molitor, Committee Member ________________________________________ Dr. Bryan K. Yamamoto, Committee Member ________________________________________ Dr. Patricia Komuniecki, Dean College of Graduate Studies The University of Toledo August 2011 Copyright 2011, Damien E. Earl This document is copyrighted material. Under copyright law, no parts of this document may be reproduced without the expressed permission of the author. An Abstract of Regulation of Neuronal L-type Voltage-Gated Calcium Channels by Flurazepam and Other Positive Allosteric GABAAR Modulators by Damien E. Earl Submitted to the Graduate Faculty as partial fulfillment of the requirements for the Doctor of Philosophy Degree in Biomedical Sciences The University of Toledo August 2011 Benzodiazpines (BZs) are clinically useful anxiolytics, sedatives, and anticonvulsants. Their mechanism of action is positive allosteric modulation of γ-aminobutyric acid type A (GABAA) receptors, the main
    [Show full text]
  • Directvote Election: Candidate Bios
    DirectVote Election: Candidate Bios President-Elect Your Voting Status: Select 0 to 1 from below. Selected: 0 Vote For: Diane Lipscombe Diane Lipscombe Administrative Accomplishments: Throughout my career, I have had numerous opportunities, with increasing complexity and scope, to combine my strong commitment to neuroscience research with my administrative leadership skills in the service of my department and at the level of the university, as well as through professional societies and non-profit organizations. I gain tremendous personal gratification from organizational problem-solving efforts that require creating new programs and improving existing ones, toward enhancing research and training in neuroscience and its communication to scientific and lay audience. I have learned the importance of community-wide engagement, effective communication, and building consensus around major issues. A key ingredient to reaching fair decisions and establishing enduring programs is seeking broad input at all levels, including from students and postdoctoral trainees, and engaging a diversity of opinions to reflect the broad community of researchers. At Brown, I have served in a number of roles that require combined administrative and scientific skills. I directed the graduate program in neuroscience for six years and since 2006, I have been the Principal Investigator on Institutional Training Grants that have supported graduate education and diversity in the Neuroscience Graduate Program at Brown. Under my leadership, the program began its successful relationship with the NIH Graduate Partnership Program. Currently, I am the Director of the Brown Institute for Brain Science, a multidisciplinary institute that engages more than 100 research laboratories in over 10 departments in both the basic and clinical sciences.
    [Show full text]
  • Characterizing Neuronal and Cardiac Isoforms of Voltage-Gated Cav1.2
    Characterizing Neuronal and Cardiac Isoforms of Voltage-Gated CaV1.2 CACNA1C Calcium Channels Kristin Marie Webster B.A., Hamilton College, 2009 Dissertation submitted in partial fulfillment of the requirements for the Degree of Doctor of Philosophy in the Department of Neuroscience at Brown University Providence, RI May 2015 Copyright © by Kristin Marie Webster. All rights reserved. ii This dissertation by Kristin Marie Webster is accepted in its present form by the Department of Neuroscience as satisfying the dissertation requirements for the Degree of Doctor of Philosophy. Date ___________ ________________________ Diane Lipscombe, Advisor Neuroscience Department Brown University Recommended to the Graduate Council Date ___________ ________________________ Anne Hart, Reader Neuroscience Department Brown University Date ___________ ________________________ Eric Morrow, Reader Molecular Cell Biology & Biochemistry Department Brown University Date ___________ ________________________ Anjali Rajadhyaksha, Reader Pediatrics Department Weil Cornell College of Medicine Approved by the Graduate Council Date ___________ ________________________ Peter Weber Dean of the Graduate School Brown University iii Kristin M. Webster Born July 29th, 1987 Princeton, NJ Brown University Residence Box GL-N, Neuroscience Graduate Program 153 Governor St Unit 2 Providence, RI 02912 USA Providence, RI 02906 USA Phone: +1 (401) 863-2615 Phone: +1 (570) 575-3651 Email: [email protected] Email: [email protected] EDUCATION Brown University Providence, RI PhD candidate in Neuroscience 2009 - Present Advisor: Professor Diane Lipscombe, PhD Hamilton College Clinton, NY BA, magna cum laude, Neuroscience, Phi Beta Kappa 2009 FELLOWSHIPS Ruth L. Kirschstein National Research Service Award from the NIMH 2012-2014 "Neuronal-Specific Splicing of CaV1.2 L-type Calcium Channels" REFFERRED PUBLICATIONS Ruz, M., Moser, A., & Webster, K.
    [Show full text]