1
|
Resveratrol Directly Controls the Activity of Neuronal Ryanodine Receptors at the Single-Channel Level. Mol Neurobiol 2019; 57:422-434. [PMID: 31376069 DOI: 10.1007/s12035-019-01705-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Accepted: 07/10/2019] [Indexed: 01/14/2023]
Abstract
Calcium ion dyshomeostasis contributes to the progression of many neurodegenerative diseases and represents a target for the development of neuroprotective therapies, as reported by Duncan et al. (Molecules 15(3):1168-95, 2010), LaFerla (Nat Rev Neurosci 3(11):862-72, 2002), and Niittykoshi et al. (Invest Ophthalmol Vis Sci 51(12):6387-93, 2010). Dysfunctional ryanodine receptors contribute to calcium ion dyshomeostasis and potentially to the pathogenesis of neurodegenerative diseases by generating abnormal calcium ion release from the endoplasmic reticulum, according to Bruno et al. (Neurobiol Aging 33(5):1001 e1-6, 2012) and Stutzmann et al. (J Neurosci 24(2):508-13, 2004). Since ryanodine receptors share functional and structural similarities with potassium channels, as reported by Lanner et al. (Cold Spring Harb Perspect Biol 2(11):a003996, 2010), and small molecules with anti-oxidant properties, such as resveratrol (3,5,4'-trihydroxy-trans-stilbene), directly control the activity of potassium channels, according to Wang et al. (J Biomed Sci 23(1):47, 2016), McCalley et al. (Molecules 19(6):7327-40, 2014), Novakovic et al. (Mol Hum Reprod 21(6):545-51, 2015), Li et al. (Cardiovasc Res 45(4):1035-45, 2000), Gopalakrishnan et al. (Br J Pharmacol 129(7):1323-32, 2000), and Hambrock et al. (J Biol Chem 282(5):3347-56, 2007), we hypothesized that trans-resveratrol can modulate intracellular calcium signaling through direct binding and functional regulation of ryanodine receptors. The goal of our study was to identify and measure the control of ryanodine receptor activity by trans-resveratrol. Mechanisms of calcium signaling mediated by the direct interaction between trans-resveratrol and ryanodine receptors were identified and measured with single-channel electrophysiology. Addition of trans-resveratrol to the cytoplasmic face of the ryanodine receptor increased single-channel activity at physiological and elevated pathophysiological cytoplasmic calcium ion concentrations. The open probability of the channel increases after interacting with the small molecule in a dose-dependent manner, but remains also dependent on the concentration of its physiological ligand, cytoplasmic-free calcium ions. This study provides the first evidence of a direct functional interaction between trans-resveratrol and ryanodine receptors. Such functional control of ryanodine receptors by trans-resveratrol as a novel mechanism of action could provide additional rationales for the development of novel therapeutic strategies to treat and prevent neurodegenerative diseases.
Collapse
|
2
|
Todd JJ, Sagar V, Lawal TA, Allen C, Razaqyar MS, Shelton MS, Chrismer IC, Zhang X, Cosgrove MM, Kuo A, Vasavada R, Jain MS, Waite M, Rajapakse D, Witherspoon JW, Wistow G, Meilleur KG. Correlation of phenotype with genotype and protein structure in RYR1-related disorders. J Neurol 2018; 265:2506-2524. [PMID: 30155738 PMCID: PMC6182665 DOI: 10.1007/s00415-018-9033-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2018] [Revised: 08/17/2018] [Accepted: 08/18/2018] [Indexed: 01/01/2023]
Abstract
Variants in the skeletal muscle ryanodine receptor 1 gene (RYR1) result in a spectrum of RYR1-related disorders. Presentation during infancy is typical and ranges from delayed motor milestones and proximal muscle weakness to severe respiratory impairment and ophthalmoplegia. We aimed to elucidate correlations between genotype, protein structure and clinical phenotype in this rare disease population. Genetic and clinical data from 47 affected individuals were analyzed and variants mapped to the cryo-EM RyR1 structure. Comparisons of clinical severity, motor and respiratory function and symptomatology were made according to the mode of inheritance and affected RyR1 structural domain(s). Overall, 49 RYR1 variants were identified in 47 cases (dominant/de novo, n = 35; recessive, n = 12). Three variants were previously unreported. In recessive cases, facial weakness, neonatal hypotonia, ophthalmoplegia/paresis, ptosis, and scapular winging were more frequently observed than in dominant/de novo cases (all, p < 0.05). Both dominant/de novo and recessive cases exhibited core myopathy histopathology. Clinically severe cases were typically recessive or had variants localized to the RyR1 cytosolic shell domain. Motor deficits were most apparent in the MFM-32 standing and transfers dimension, [median (IQR) 85.4 (18.8)% of maximum score] and recessive cases exhibited significantly greater overall motor function impairment compared to dominant/de novo cases [79.7 (18.8)% vs. 87.5 (17.7)% of maximum score, p = 0.03]. Variant mapping revealed patterns of clinical severity across RyR1 domains, including a structural plane of interest within the RyR1 cytosolic shell, in which 84% of variants affected the bridging solenoid. We have corroborated genotype-phenotype correlations and identified RyR1 regions that may be especially sensitive to structural modification.
Collapse
Affiliation(s)
- Joshua J Todd
- Neuromuscular Symptoms Unit, Tissue Injury Branch, National Institute of Nursing Research, National Institutes of Health, 10 Center Drive, Room 2A07, Bethesda, MD, 20892, USA.
| | - Vatsala Sagar
- Section on Molecular Structure and Functional Genomics, National Eye Institute, National Institutes of Health, Bethesda, MD, USA
| | - Tokunbor A Lawal
- Neuromuscular Symptoms Unit, Tissue Injury Branch, National Institute of Nursing Research, National Institutes of Health, 10 Center Drive, Room 2A07, Bethesda, MD, 20892, USA
| | - Carolyn Allen
- Neuromuscular Symptoms Unit, Tissue Injury Branch, National Institute of Nursing Research, National Institutes of Health, 10 Center Drive, Room 2A07, Bethesda, MD, 20892, USA
| | - Muslima S Razaqyar
- Neuromuscular Symptoms Unit, Tissue Injury Branch, National Institute of Nursing Research, National Institutes of Health, 10 Center Drive, Room 2A07, Bethesda, MD, 20892, USA
| | - Monique S Shelton
- Neuromuscular Symptoms Unit, Tissue Injury Branch, National Institute of Nursing Research, National Institutes of Health, 10 Center Drive, Room 2A07, Bethesda, MD, 20892, USA
| | - Irene C Chrismer
- Neuromuscular Symptoms Unit, Tissue Injury Branch, National Institute of Nursing Research, National Institutes of Health, 10 Center Drive, Room 2A07, Bethesda, MD, 20892, USA
| | - Xuemin Zhang
- Neuromuscular Symptoms Unit, Tissue Injury Branch, National Institute of Nursing Research, National Institutes of Health, 10 Center Drive, Room 2A07, Bethesda, MD, 20892, USA
| | - Mary M Cosgrove
- Neuromuscular Symptoms Unit, Tissue Injury Branch, National Institute of Nursing Research, National Institutes of Health, 10 Center Drive, Room 2A07, Bethesda, MD, 20892, USA
| | - Anna Kuo
- Neuromuscular Symptoms Unit, Tissue Injury Branch, National Institute of Nursing Research, National Institutes of Health, 10 Center Drive, Room 2A07, Bethesda, MD, 20892, USA
| | - Ruhi Vasavada
- Mark O. Hatfield Clinical Research Center, Rehabilitation Medicine Department, National Institutes of Health, Bethesda, MD, USA
| | - Minal S Jain
- Mark O. Hatfield Clinical Research Center, Rehabilitation Medicine Department, National Institutes of Health, Bethesda, MD, USA
| | - Melissa Waite
- Mark O. Hatfield Clinical Research Center, Rehabilitation Medicine Department, National Institutes of Health, Bethesda, MD, USA
| | - Dinusha Rajapakse
- Section on Molecular Structure and Functional Genomics, National Eye Institute, National Institutes of Health, Bethesda, MD, USA
| | - Jessica W Witherspoon
- Neuromuscular Symptoms Unit, Tissue Injury Branch, National Institute of Nursing Research, National Institutes of Health, 10 Center Drive, Room 2A07, Bethesda, MD, 20892, USA
| | - Graeme Wistow
- Section on Molecular Structure and Functional Genomics, National Eye Institute, National Institutes of Health, Bethesda, MD, USA
| | - Katherine G Meilleur
- Neuromuscular Symptoms Unit, Tissue Injury Branch, National Institute of Nursing Research, National Institutes of Health, 10 Center Drive, Room 2A07, Bethesda, MD, 20892, USA
| |
Collapse
|
3
|
Gaburjakova M, Gaburjakova J. Insight towards the identification of cytosolic Ca 2+ -binding sites in ryanodine receptors from skeletal and cardiac muscle. Acta Physiol (Oxf) 2017; 219:757-767. [PMID: 27543850 DOI: 10.1111/apha.12772] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 07/13/2016] [Accepted: 08/12/2016] [Indexed: 11/30/2022]
Abstract
Ca2+ plays a critical role in several processes involved in skeletal and cardiac muscle contraction. One key step in cardiac excitation-contraction (E-C) coupling is the activation of the cardiac ryanodine receptor (RYR2) by cytosolic Ca2+ elevations. Although this process is not critical for skeletal E-C coupling, the activation and inhibition of the skeletal ryanodine receptor (RYR1) seem to be important for overall muscle function. The RYR1 and RYR2 channels fall within the large category of Ca2+ -binding proteins that harbour highly selective Ca2+ -binding sites to receive and translate the various Ca2+ signals into specific functional responses. However, little is known about the precise localization of these sites within the cytosolic assembly of both RYR isoforms, although several experimental lines of evidence have highlighted their EF-hand nature. EF-hand proteins share a common helix-loop-helix structural motif with highly conserved residues involved in Ca2+ coordination. The first step in predicting EF-hand positive regions is to compare the primary protein structure with the EF-hand motif by employing available bioinformatics tools. Although this simple method narrows down search regions, it does not provide solid evidence regarding which regions bind Ca2+ in both RYR isoforms. In this review, we seek to highlight the key findings and experimental approaches that should strengthen our future efforts to identify the cytosolic Ca2+ -binding sites responsible for activation and inhibition in the RYR1 channel, as much less work has been conducted on the RYR2 channel.
Collapse
Affiliation(s)
- M. Gaburjakova
- Institute of Molecular Physiology and Genetics; Slovak Academy of Sciences; Bratislava Slovak Republic
| | - J. Gaburjakova
- Institute of Molecular Physiology and Genetics; Slovak Academy of Sciences; Bratislava Slovak Republic
| |
Collapse
|
4
|
Schilling R, Fink RHA, Fischer WB. Interaction of ions with the luminal sides of wild-type and mutated skeletal muscle ryanodine receptors. J Mol Model 2016; 22:37. [PMID: 26781665 DOI: 10.1007/s00894-015-2906-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2015] [Accepted: 12/28/2015] [Indexed: 12/22/2022]
Abstract
Ryanodine receptors (RyRs) are the largest known ion channels, and are of central importance for the release of Ca(2+) from the sarco/endoplasmic reticulum (SR/ER) in a variety of cells. In cardiac and skeletal muscle cells, contraction is triggered by the release of Ca(2+) into the cytoplasm and thus depends crucially on correct RyR function. In this work, in silico mutants of the RyR pore were generated and MD simulations were conducted to examine the impact of the mutations on the Ca(2+) distribution. The Ca(2+) distribution pattern on the luminal side of the RyR was most affected by G4898R, D4899Q, E4900Q, R4913E, and D4917A mutations. MD simulations with our wild-type model and various ion species showed a preference for Ca(2+) over other cations at the luminal pore entrance. This Ca(2+)-accumulating characteristic of the luminal RyR side may be essential to the conductance properties of the channel.
Collapse
Affiliation(s)
- Roman Schilling
- Medical Biophysics Group, Institute of Physiology and Pathophysiology, University of Heidelberg, 69120, Heidelberg, Germany
| | - Rainer H A Fink
- Medical Biophysics Group, Institute of Physiology and Pathophysiology, University of Heidelberg, 69120, Heidelberg, Germany
| | - Wolfgang B Fischer
- Institute of Biophotonics, School of Biomedical Science and Engineering, National Yang-Ming University, 155, Li-Non St., Sec. 2, Taipei, 112, Taiwan.
- Biophotonics & Molecular Imaging Research Center (BMIRC), National Yang-Ming University, Taipei, 112, Taiwan.
| |
Collapse
|
5
|
FRET-based trilateration of probes bound within functional ryanodine receptors. Biophys J 2015; 107:2037-48. [PMID: 25418089 DOI: 10.1016/j.bpj.2014.09.029] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 09/08/2014] [Accepted: 09/19/2014] [Indexed: 02/05/2023] Open
Abstract
To locate the biosensor peptide DPc10 bound to ryanodine receptor (RyR) Ca(2+) channels, we developed an approach that combines fluorescence resonance energy transfer (FRET), simulated-annealing, cryo-electron microscopy, and crystallographic data. DPc10 is identical to the 2460-2495 segment within the cardiac muscle RyR isoform (RyR2) central domain. DPc10 binding to RyR2 results in a pathologically elevated Ca(2+) leak by destabilizing key interactions between the RyR2 N-terminal and central domains (unzipping). To localize the DPc10 binding site within RyR2, we measured FRET between five single-cysteine variants of the FK506-binding protein (FKBP) labeled with a donor probe, and DPc10 labeled with an acceptor probe (A-DPc10). Effective donor positions were calculated from simulated-annealing constrained by both the RyR cryo-EM map and the FKBP atomic structure docked to the RyR. FRET to A-DPc10 was measured in permeabilized cardiomyocytes via confocal microscopy, converted to distances, and used to trilaterate the acceptor locus within RyR. Additional FRET measurements between donor-labeled calmodulin and A-DPc10 were used to constrain the trilaterations. Results locate the DPc10 probe within RyR domain 3, ?35 Å from the previously docked N-terminal domain crystal structure. This multiscale approach may be useful in mapping other RyR sites of mechanistic interest within FRET range of FKBP.
Collapse
|
6
|
Bannister ML, Thomas NL, Sikkel MB, Mukherjee S, Maxwell C, MacLeod KT, George CH, Williams AJ. The mechanism of flecainide action in CPVT does not involve a direct effect on RyR2. Circ Res 2015; 116:1324-35. [PMID: 25648700 DOI: 10.1161/circresaha.116.305347] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Accepted: 02/03/2015] [Indexed: 12/17/2022]
Abstract
RATIONALE Flecainide, a class 1c antiarrhythmic, has emerged as an effective therapy in preventing arrhythmias in patients with catecholaminergic polymorphic ventricular tachycardia (CPVT) refractory to β-adrenergic receptor blockade. It has been proposed that the clinical efficacy of flecainide in CPVT is because of the combined actions of direct blockade of ryanodine receptors (RyR2) and Na(+) channel inhibition. However, there is presently no direct evidence to support the notion that flecainide blocks RyR2 Ca(2+) flux in the physiologically relevant (luminal-to-cytoplasmic) direction. The mechanism of flecainide action remains controversial. OBJECTIVE To examine, in detail, the effect of flecainide on the human RyR2 channel and to establish whether the direct blockade of physiologically relevant RyR2 ion flow by the drug contributes to its therapeutic efficacy in the clinical management of CPVT. METHODS AND RESULTS Using single-channel analysis, we show that, even at supraphysiological concentrations, flecainide did not inhibit the physiologically relevant, luminal-to-cytosolic flux of cations through the channel. Moreover, flecainide did not alter RyR2 channel gating and had negligible effect on the mechanisms responsible for the sarcoplasmic reticulum charge-compensating counter current. Using permeabilized cardiac myocytes to eliminate any contribution of plasmalemmal Na(+) channels to the observed actions of the drug at the cellular level, flecainide did not inhibit RyR2-dependent sarcoplasmic reticulum Ca(2+) release. CONCLUSIONS The principal action of flecainide in CPVT is not via a direct interaction with RyR2. Our data support a model of flecainide action in which Na(+)-dependent modulation of intracellular Ca(2+) handling attenuates RyR2 dysfunction in CPVT.
Collapse
Affiliation(s)
- Mark L Bannister
- From the Institute of Molecular and Experimental Medicine, Wales Heart Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom (M.L.B., N.L.T., S.M., C.M., C.H.G., A.J.W.); and Myocardial Function Section, National Heart and Lung Institute, Imperial College London, London, United Kingdom (M.B.S., K.T.M.)
| | - N Lowri Thomas
- From the Institute of Molecular and Experimental Medicine, Wales Heart Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom (M.L.B., N.L.T., S.M., C.M., C.H.G., A.J.W.); and Myocardial Function Section, National Heart and Lung Institute, Imperial College London, London, United Kingdom (M.B.S., K.T.M.)
| | - Markus B Sikkel
- From the Institute of Molecular and Experimental Medicine, Wales Heart Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom (M.L.B., N.L.T., S.M., C.M., C.H.G., A.J.W.); and Myocardial Function Section, National Heart and Lung Institute, Imperial College London, London, United Kingdom (M.B.S., K.T.M.)
| | - Saptarshi Mukherjee
- From the Institute of Molecular and Experimental Medicine, Wales Heart Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom (M.L.B., N.L.T., S.M., C.M., C.H.G., A.J.W.); and Myocardial Function Section, National Heart and Lung Institute, Imperial College London, London, United Kingdom (M.B.S., K.T.M.)
| | - Chloe Maxwell
- From the Institute of Molecular and Experimental Medicine, Wales Heart Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom (M.L.B., N.L.T., S.M., C.M., C.H.G., A.J.W.); and Myocardial Function Section, National Heart and Lung Institute, Imperial College London, London, United Kingdom (M.B.S., K.T.M.)
| | - Kenneth T MacLeod
- From the Institute of Molecular and Experimental Medicine, Wales Heart Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom (M.L.B., N.L.T., S.M., C.M., C.H.G., A.J.W.); and Myocardial Function Section, National Heart and Lung Institute, Imperial College London, London, United Kingdom (M.B.S., K.T.M.)
| | - Christopher H George
- From the Institute of Molecular and Experimental Medicine, Wales Heart Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom (M.L.B., N.L.T., S.M., C.M., C.H.G., A.J.W.); and Myocardial Function Section, National Heart and Lung Institute, Imperial College London, London, United Kingdom (M.B.S., K.T.M.)
| | - Alan J Williams
- From the Institute of Molecular and Experimental Medicine, Wales Heart Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom (M.L.B., N.L.T., S.M., C.M., C.H.G., A.J.W.); and Myocardial Function Section, National Heart and Lung Institute, Imperial College London, London, United Kingdom (M.B.S., K.T.M.).
| |
Collapse
|
7
|
Shirvanyants D, Ramachandran S, Mei Y, Xu L, Meissner G, Dokholyan NV. Pore dynamics and conductance of RyR1 transmembrane domain. Biophys J 2014; 106:2375-84. [PMID: 24896116 PMCID: PMC4052289 DOI: 10.1016/j.bpj.2014.04.023] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Accepted: 04/17/2014] [Indexed: 11/25/2022] Open
Abstract
Ryanodine receptors (RyR) are calcium release channels, playing a major role in the regulation of muscular contraction. Mutations in skeletal muscle RyR (RyR1) are associated with congenital diseases such as malignant hyperthermia and central core disease (CCD). The absence of high-resolution structures of RyR1 has limited our understanding of channel function and disease mechanisms at the molecular level. Previously, we have reported a hypothetical structure of the RyR1 pore-forming region, obtained by homology modeling and supported by mutational scans, electrophysiological measurements, and cryo-electron microscopy. Here, we utilize the expanded model encompassing six transmembrane helices to calculate the RyR1 pore region conductance, to analyze its structural stability, and to hypothesize the mechanism of the Ile4897 CCD-associated mutation. The calculated conductance of the wild-type RyR1 suggests that the proposed pore structure can sustain ion currents measured in single-channel experiments. We observe a stable pore structure on timescales of 0.2 μs, with multiple cations occupying the selectivity filter and cytosolic vestibule, but not the inner chamber. We further suggest that stability of the selectivity filter critically depends on the interactions between the I4897 residue and several hydrophobic residues of the neighboring subunit. Loss of these interactions in the case of polar substitution I4897T results in destabilization of the selectivity filter, a possible cause of the CCD-specific reduced Ca(2+) conductance.
Collapse
Affiliation(s)
- David Shirvanyants
- Department of Biochemistry and Biophysics, School of Medicine, University of North Carolina, Chapel Hill, North Carolina
| | - Srinivas Ramachandran
- Department of Biochemistry and Biophysics, School of Medicine, University of North Carolina, Chapel Hill, North Carolina
| | - Yingwu Mei
- Department of Biochemistry and Biophysics, School of Medicine, University of North Carolina, Chapel Hill, North Carolina
| | - Le Xu
- Department of Biochemistry and Biophysics, School of Medicine, University of North Carolina, Chapel Hill, North Carolina
| | - Gerhard Meissner
- Department of Biochemistry and Biophysics, School of Medicine, University of North Carolina, Chapel Hill, North Carolina.
| | - Nikolay V Dokholyan
- Department of Biochemistry and Biophysics, School of Medicine, University of North Carolina, Chapel Hill, North Carolina.
| |
Collapse
|
8
|
Schilling R, Fink RH, Fischer WB. MD simulations of the central pore of ryanodine receptors and sequence comparison with 2B protein from coxsackie virus. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2014; 1838:1122-31. [DOI: 10.1016/j.bbamem.2013.12.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Revised: 11/16/2013] [Accepted: 12/12/2013] [Indexed: 02/08/2023]
|
9
|
Baran I, Ganea C. RyR3 in situ regulation by Ca2+ and quercetin and the RyR3-mediated Ca2+ release flux in intact Jurkat cells. Arch Biochem Biophys 2013; 540:145-59. [DOI: 10.1016/j.abb.2013.10.024] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Revised: 10/19/2013] [Accepted: 10/29/2013] [Indexed: 11/27/2022]
|
10
|
Euden J, Mason SA, Williams AJ. Functional characterization of the cardiac ryanodine receptor pore-forming region. PLoS One 2013; 8:e66542. [PMID: 23776685 PMCID: PMC3680380 DOI: 10.1371/journal.pone.0066542] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Accepted: 05/07/2013] [Indexed: 01/16/2023] Open
Abstract
Ryanodine receptors are homotetrameric intracellular calcium release channels. The efficiency of these channels is underpinned by exceptional rates of cation translocation through the open channel and this is achieved at the expense of the high degree of selectivity characteristic of many other types of channel. Crystallization of prokaryotic potassium channels has provided insights into the structures and mechanisms responsible for ion selection and movement in these channels, however no equivalent structural detail is currently available for ryanodine receptors. Nevertheless both molecular modeling and cryo-electron microscopy have identified the probable pore-forming region (PFR) of the ryanodine receptor (RyR) and suggest that this region contains structural elements equivalent to those of the PFRs of potassium-selective channels. The aim of the current study was to establish if the isolated putative cardiac RyR (RyR2) PFR could form a functional ion channel. We have expressed and purified the RyR2 PFR and shown that function is retained following reconstitution into planar phospholipid bilayers. Our data provide the first direct experimental evidence to support the proposal that the conduction pathway of RyR2 is formed by structural elements equivalent to those of the potassium channel PFR.
Collapse
Affiliation(s)
- Joanne Euden
- Institute of Molecular and Experimental Medicine, Cardiff University, Cardiff, United Kingdom.
| | | | | |
Collapse
|
11
|
Euden J, Mason SA, Viero C, Thomas NL, Williams AJ. Investigations of the contribution of a putative glycine hinge to ryanodine receptor channel gating. J Biol Chem 2013; 288:16671-16679. [PMID: 23632022 PMCID: PMC3675601 DOI: 10.1074/jbc.m113.465310] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Ryanodine receptor channels (RyR) are key components of striated muscle excitation-contraction coupling, and alterations in their function underlie both inherited and acquired disease. A full understanding of the disease process will require a detailed knowledge of the mechanisms and structures involved in RyR function. Unfortunately, high-resolution structural data, such as exist for K+-selective channels, are not available for RyR. In the absence of these data, we have used modeling to identify similarities in the structural elements of K+ channel pore-forming regions and postulated equivalent regions of RyR. This has identified a sequence of residues in the cytosolic cavity-lining transmembrane helix of RyR (G4864LIIDA4869 in RyR2) analogous to the glycine hinge motif present in many K+ channels. Gating in these K+ channels can be disrupted by substitution of residues for the hinge glycine. We investigated the involvement of glycine 4864 in RyR2 gating by monitoring properties of recombinant human RyR2 channels in which this glycine is replaced by residues that alter gating in K+ channels. Our data demonstrate that introducing alanine at position 4864 produces no significant change in RyR2 function. In contrast, function is altered when glycine 4864 is replaced by either valine or proline, the former preventing channel opening and the latter modifying both ion translocation and gating. Our studies reveal novel information on the structural basis of RyR gating, identifying both similarities with, and differences from, K+ channels. Glycine 4864 is not absolutely required for channel gating, but some flexibility at this point in the cavity-lining transmembrane helix is necessary for normal RyR function.
Collapse
Affiliation(s)
- Joanne Euden
- Institute of Molecular and Experimental Medicine, Cardiff University, Cardiff CF14 4XN, Wales, United Kingdom
| | - Sammy A Mason
- Institute of Molecular and Experimental Medicine, Cardiff University, Cardiff CF14 4XN, Wales, United Kingdom
| | - Cedric Viero
- Institute of Molecular and Experimental Medicine, Cardiff University, Cardiff CF14 4XN, Wales, United Kingdom
| | - N Lowri Thomas
- Institute of Molecular and Experimental Medicine, Cardiff University, Cardiff CF14 4XN, Wales, United Kingdom
| | - Alan J Williams
- Institute of Molecular and Experimental Medicine, Cardiff University, Cardiff CF14 4XN, Wales, United Kingdom.
| |
Collapse
|
12
|
Zhou H, Rokach O, Feng L, Munteanu I, Mamchaoui K, Wilmshurst JM, Sewry C, Manzur AY, Pillay K, Mouly V, Duchen M, Jungbluth H, Treves S, Muntoni F. RyR1 Deficiency in Congenital Myopathies Disrupts Excitation-Contraction Coupling. Hum Mutat 2013; 34:986-96. [DOI: 10.1002/humu.22326] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Accepted: 03/18/2013] [Indexed: 11/08/2022]
Affiliation(s)
- Haiyan Zhou
- Dubowitz Neuromuscular Centre; Institute of Child Health, University College London; London UK
| | - Ori Rokach
- Department of Anaesthesia and Biomedicine; Basel University and University Hospital Basel; Basel Switzerland
| | - Lucy Feng
- Dubowitz Neuromuscular Centre; Institute of Child Health, University College London; London UK
| | - Iulia Munteanu
- Dubowitz Neuromuscular Centre; Institute of Child Health, University College London; London UK
| | - Kamel Mamchaoui
- UM76 Université Pierre et Marie Curie; UMRS974 INSERM, UMR 7215 CNRS, Institut de Myologie AIM, Groupe hospitalier Pitié-Salpétrière, 47 bd de I'Hôpital; Paris France
| | - Jo M. Wilmshurst
- Department of Paediatric Neurology; School of Child and Adolescent Health, University of Cape Town, Red Cross Children's Hospital; Cape Town South Africa
| | - Caroline Sewry
- Dubowitz Neuromuscular Centre; Institute of Child Health, University College London; London UK
| | - Adnan Y. Manzur
- Dubowitz Neuromuscular Centre; Institute of Child Health, University College London; London UK
| | - Komala Pillay
- Department of Paediatric Pathology; School of Child and Adolescent Health, University of Cape Town, Red Cross Children's Hospital; Cape Town South Africa
| | - Vincent Mouly
- Department of Anaesthesia and Biomedicine; Basel University and University Hospital Basel; Basel Switzerland
| | - Michael Duchen
- Cell and Developmental Biology; University College London; London UK
| | - Heinz Jungbluth
- Department of Paediatric Neurology; Evelina Children's Hospital; London UK
- Clinical Neuroscience Division; IoP, King's College; London UK
- Randall Division of Cell and Molecular Biophysics; Muscle Signalling Group; King's College London; London UK
| | - Susan Treves
- Department of Anaesthesia and Biomedicine; Basel University and University Hospital Basel; Basel Switzerland
- Department of Life Sciences; University of Ferrara; Ferrara Italy
| | - Francesco Muntoni
- Dubowitz Neuromuscular Centre; Institute of Child Health, University College London; London UK
| |
Collapse
|
13
|
Chang X, Jin Y, Zhao H, Huang Q, Wang J, Yuan Y, Han Y, Qin J. Clinical features and ryanodine receptor type 1 gene mutation analysis in a Chinese family with central core disease. J Child Neurol 2013; 28:384-8. [PMID: 22550088 DOI: 10.1177/0883073812441251] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Central core disease is a rare inherited neuromuscular disorder caused by mutations in ryanodine receptor type 1 gene. The clinical phenotype of the disease is highly variable. We report a Chinese pedigree with central core disease confirmed by the gene sequencing. All 3 patients in the family presented with mild proximal limb weakness. The serum level of creatine kinase was normal, and electromyography suggested myogenic changes. The histologic analysis of muscle biopsy showed identical central core lesions in almost all of the muscle fibers in the index case. Exon 90-106 in the C-terminal domain of the ryanodine receptor type 1 gene was amplified using polymerase chain reaction. One heterozygous missense mutation G14678A (Arg4893Gln) in exon 102 was identified in all 3 patients. This is the first report of a familial case of central core disease confirmed by molecular study in mainland China.
Collapse
Affiliation(s)
- Xingzhi Chang
- Department of Pediatrics, Peking University First Hospital, Beijing, PR China
| | | | | | | | | | | | | | | |
Collapse
|
14
|
Lefebvre R, Legrand C, Groom L, Dirksen RT, Jacquemond V. Ca2+ release in muscle fibers expressing R4892W and G4896V type 1 ryanodine receptor disease mutants. PLoS One 2013; 8:e54042. [PMID: 23308296 PMCID: PMC3538700 DOI: 10.1371/journal.pone.0054042] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Accepted: 12/05/2012] [Indexed: 12/17/2022] Open
Abstract
The large and rapidly increasing number of potentially pathological mutants in the type 1 ryanodine receptor (RyR1) prompts the need to characterize their effects on voltage-activated sarcoplasmic reticulum (SR) Ca2+ release in skeletal muscle. Here we evaluated the function of the R4892W and G4896V RyR1 mutants, both associated with central core disease (CCD) in humans, in myotubes and in adult muscle fibers. For both mutants expressed in RyR1-null (dyspedic) myotubes, voltage-gated Ca2+ release was absent following homotypic expression and only partially restored following heterotypic expression with wild-type (WT) RyR1. In muscle fibers from adult WT mice, both mutants were expressed in restricted regions of the fibers with a pattern consistent with triadic localization. Voltage-clamp-activated confocal Ca2+ signals showed that fiber regions endowed with G4896V-RyR1s exhibited an ∼30% reduction in the peak rate of SR Ca2+ release, with no significant change in SR Ca2+ content. Immunostaining revealed no associated change in the expression of either α1S subunit (Cav1.1) of the dihydropyridine receptor (DHPR) or type 1 sarco(endo)plasmic reticulum Ca2+ ATPase (SERCA1), indicating that the reduced Ca2+ release resulted from defective RyR1 function. Interestingly, in spite of robust localized junctional expression, the R4892W mutant did not affect SR Ca2+ release in adult muscle fibers, consistent with a low functional penetrance of this particular CCD-associated mutant.
Collapse
Affiliation(s)
- Romain Lefebvre
- Centre de Génétique et de Physiologie Moléculaire et Cellulaire, CNRS UMR 5534 – Université Lyon 1, Villeurbanne, France
| | - Claude Legrand
- Centre de Génétique et de Physiologie Moléculaire et Cellulaire, CNRS UMR 5534 – Université Lyon 1, Villeurbanne, France
| | - Linda Groom
- Department of Pharmacology and Physiology, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Robert T. Dirksen
- Department of Pharmacology and Physiology, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Vincent Jacquemond
- Centre de Génétique et de Physiologie Moléculaire et Cellulaire, CNRS UMR 5534 – Université Lyon 1, Villeurbanne, France
- * E-mail:
| |
Collapse
|
15
|
Bhanumathy C, da Fonseca PCA, Morris EP, Joseph SK. Identification of functionally critical residues in the channel domain of inositol trisphosphate receptors. J Biol Chem 2012; 287:43674-84. [PMID: 23086950 PMCID: PMC3527953 DOI: 10.1074/jbc.m112.415786] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
We have combined alanine mutagenesis and functional assays to identify amino acid residues in the channel domain that are critical for inositol 1,4,5-trisphosphate receptor (IP(3)R) channel function. The residues selected were highly conserved in all three IP(3)R isoforms and were located in the cytosolic end of the S6 pore-lining helix and proximal portion of the C-tail. Two adjacent hydrophobic amino acids (Ile-2588 and Ile-2589) at the putative cytosolic interface of the S6 helix inactivated channel function and could be candidates for the channel gate. Of five negatively charged residues mutated, none completely eliminated channel function. Of five positively charged residues mutated, only one inactivated the channel (Arg-2596). In addition to the previously identified role of a pair of cysteines in the C-tail (Cys-2610 and Cys-2613), a pair of highly conserved histidines (His-2630 and His-2635) were also essential for channel function. Expression of the H2630A and H2635A mutants (but not R2596A) produced receptors with destabilized interactions between the N-terminal fragment and the channel domain. A previously unrecognized association between the cytosolic C-tail and the TM 4,5-loop was demonstrated using GST pulldown assays. However, none of the mutations in the C-tail interfered with this interaction or altered the ability of the C-tail to assemble into dimers. Our present findings and recent information on IP(3)R structure from electron microscopy and crystallography are incorporated into a revised model of channel gating.
Collapse
MESH Headings
- Amino Acid Substitution
- Animals
- COS Cells
- Chlorocebus aethiops
- HEK293 Cells
- Humans
- Inositol 1,4,5-Trisphosphate Receptors/chemistry
- Inositol 1,4,5-Trisphosphate Receptors/genetics
- Inositol 1,4,5-Trisphosphate Receptors/metabolism
- Ion Channel Gating/physiology
- Models, Molecular
- Mutation, Missense
- Protein Multimerization/physiology
- Protein Structure, Secondary
- Protein Structure, Tertiary
- Rats
Collapse
Affiliation(s)
- Cunnigaiper Bhanumathy
- From the Department of Pathology and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107 and
| | - Paula C. A. da Fonseca
- the Institute for Cancer Research, Chester Beatty Laboratories, London, SW3 6JB, United Kingdom
| | - Edward P. Morris
- the Institute for Cancer Research, Chester Beatty Laboratories, London, SW3 6JB, United Kingdom
| | - Suresh K. Joseph
- From the Department of Pathology and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107 and
- To whom correspondence should be addressed: Dept. of Pathology & Cell Biology, Rm. 230A JAH, 1020 Locust St., Philadelphia, PA 19107. Tel.: 215-503-1222; E-mail:
| |
Collapse
|
16
|
Finnerty JJ, Eisenberg R, Carloni P. Localizing the Charged Side Chains of Ion Channels within the Crowded Charge Models. J Chem Theory Comput 2012; 9:766-73. [DOI: 10.1021/ct300768j] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Justin J. Finnerty
- Computational Biophysics, German
Research School for Simulation Sciences, 52425 Jülich, Germany
| | - Robert Eisenberg
- Department of Molecular Biophysics
and Physiology, Rush University, Chicago, Illinois 60612, United States
| | - Paolo Carloni
- Computational Biophysics, German
Research School for Simulation Sciences, 52425 Jülich, Germany
and Institute for Advanced Simulation IAS-5, Computational Biomedicine,
Forschungszentrum Jülich, 52425 Jülich, Germany
| |
Collapse
|
17
|
Mapping domains and mutations on the skeletal muscle ryanodine receptor channel. Trends Mol Med 2012; 18:644-57. [DOI: 10.1016/j.molmed.2012.09.006] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2012] [Revised: 08/14/2012] [Accepted: 09/19/2012] [Indexed: 11/20/2022]
|
18
|
Poulsen H, Nissen P, Mouritsen OG, Khandelia H. Protein kinase A (PKA) phosphorylation of Na+/K+-ATPase opens intracellular C-terminal water pathway leading to third Na+-binding site in molecular dynamics simulations. J Biol Chem 2012; 287:15959-65. [PMID: 22433860 DOI: 10.1074/jbc.m112.340406] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Phosphorylation is one of the major mechanisms for posttranscriptional modification of proteins. The addition of a compact, negatively charged moiety to a protein can significantly change its function and localization by affecting its structure and interaction network. We have used all-atom Molecular Dynamics simulations to investigate the structural consequences of phosphorylating the Na(+)/K(+)-ATPase (NKA) residue Ser(936), which is the best characterized phosphorylation site in NKA, targeted in vivo by protein kinase A (PKA). The Molecular Dynamics simulations suggest that Ser(936) phosphorylation opens a C-terminal hydrated pathway leading to Asp(926), a transmembrane residue proposed to form part of the third sodium ion-binding site. Simulations of a S936E mutant form, for which only subtle effects are observed when expressed in Xenopus oocytes and studied with electrophysiology, does not mimic the effects of Ser(936) phosphorylation. The results establish a structural association of Ser(936) with the C terminus of NKA and indicate that phosphorylation of Ser(936) can modulate pumping activity by changing the accessibility to the ion-binding site.
Collapse
Affiliation(s)
- Hanne Poulsen
- PUMPKIN-Centre for Membrane Pumps in Cells and Disease, Aarhus University, Aarhus 8000 C, Denmark
| | | | | | | |
Collapse
|
19
|
Type 1 ryanodine receptor knock-in mutation causing central core disease of skeletal muscle also displays a neuronal phenotype. Proc Natl Acad Sci U S A 2011; 109:610-5. [PMID: 22203976 DOI: 10.1073/pnas.1115111108] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The type 1 ryanodine receptor (RyR1) is expressed widely in the brain, with high levels in the cerebellum, hippocampus, and hypothalamus. We have shown that L-type Ca(2+) channels in terminals of hypothalamic magnocellular neurons are coupled to RyRs, as they are in skeletal muscle, allowing voltage-induced Ca(2+) release (VICaR) from internal Ca(2+) stores without Ca(2+) influx. Here we demonstrate that RyR1 plays a role in VICaR in nerve terminals. Furthermore, in heterozygotes from the Ryr1(I4895T/WT) (IT/+) mouse line, carrying a knock-in mutation corresponding to one that causes a severe form of human central core disease, VICaR is absent, demonstrating that type 1 RyR mediates VICaR and that these mice have a neuronal phenotype. The absence of VICaR was shown in two ways: first, depolarization in the absence of Ca(2+) influx elicited Ca(2+)syntillas (scintilla, spark, in a nerve terminal, a SYNaptic structure) in WT, but not in mutant terminals; second, in the presence of extracellular Ca(2+), IT/+ terminals showed a twofold decrease in global Ca(2+) transients, with no change in plasmalemmal Ca(2+) current. From these studies we draw two conclusions: (i) RyR1 plays a role in VICaR in hypothalamic nerve terminals; and (ii) a neuronal alteration accompanies the myopathy in IT/+ mice, and, possibly in humans carrying the corresponding RyR1 mutation.
Collapse
|
20
|
Diaz-Sylvester PL, Porta M, Copello JA. Modulation of cardiac ryanodine receptor channels by alkaline earth cations. PLoS One 2011; 6:e26693. [PMID: 22039534 PMCID: PMC3198824 DOI: 10.1371/journal.pone.0026693] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2011] [Accepted: 10/02/2011] [Indexed: 01/20/2023] Open
Abstract
Cardiac ryanodine receptor (RyR2) function is modulated by Ca(2+) and Mg(2+). To better characterize Ca(2+) and Mg(2+) binding sites involved in RyR2 regulation, the effects of cytosolic and luminal earth alkaline divalent cations (M(2+): Mg(2+), Ca(2+), Sr(2+), Ba(2+)) were studied on RyR2 from pig ventricle reconstituted in bilayers. RyR2 were activated by M(2+) binding to high affinity activating sites at the cytosolic channel surface, specific for Ca(2+) or Sr(2+). This activation was interfered by Mg(2+) and Ba(2+) acting at low affinity M(2+)-unspecific binding sites. When testing the effects of luminal M(2+) as current carriers, all M(2+) increased maximal RyR2 open probability (compared to Cs(+)), suggesting the existence of low affinity activating M(2+)-unspecific sites at the luminal surface. Responses to M(2+) vary from channel to channel (heterogeneity). However, with luminal Ba(2+)or Mg(2+), RyR2 were less sensitive to cytosolic Ca(2+) and caffeine-mediated activation, openings were shorter and voltage-dependence was more marked (compared to RyR2 with luminal Ca(2+)or Sr(2+)). Kinetics of RyR2 with mixtures of luminal Ba(2+)/Ca(2+) and additive action of luminal plus cytosolic Ba(2+) or Mg(2+) suggest luminal M(2+) differentially act on luminal sites rather than accessing cytosolic sites through the pore. This suggests the presence of additional luminal activating Ca(2+)/Sr(2+)-specific sites, which stabilize high P(o) mode (less voltage-dependent) and increase RyR2 sensitivity to cytosolic Ca(2+) activation. In summary, RyR2 luminal and cytosolic surfaces have at least two sets of M(2+) binding sites (specific for Ca(2+) and unspecific for Ca(2+)/Mg(2+)) that dynamically modulate channel activity and gating status, depending on SR voltage.
Collapse
Affiliation(s)
- Paula L. Diaz-Sylvester
- Department of Pharmacology, Southern Illinois School of Medicine, Springfield, Illinois, United States of America
| | - Maura Porta
- Department of Physiology, Midwestern University, Downers Grove, Illinois, United States of America
| | - Julio A. Copello
- Department of Pharmacology, Southern Illinois School of Medicine, Springfield, Illinois, United States of America
- * E-mail:
| |
Collapse
|
21
|
Haraki T, Yasuda T, Mukaida K, Migita T, Hamada H, Kawamoto M. Mutated p.4894 RyR1 function related to malignant hyperthermia and congenital neuromuscular disease with uniform type 1 fiber (CNMDU1). Anesth Analg 2011; 113:1461-7. [PMID: 21926372 DOI: 10.1213/ane.0b013e318232053e] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Ryanodine receptor 1 (RyR1) is a Ca(2+) release channel located in the sarcoplasmic reticulum membrane of skeletal muscle. More than 200 variants in RyR1 have been identified in DNA from patients with malignant hyperthermia (MH) and congenital myopathies; only 30 have been sufficiently studied so as to be identified as MH-causative mutations. The Ala4894Thr RyR1 variant was found in a Japanese patient with susceptibility to MH, and the Ala4894Pro variant in a rare case of myopathy: congenital neuromuscular disease with uniform type 1 fiber (CNMDU1). We hypothesized that different Ala4894 variants of RyR1 cause different pathophysiological changes that are identifiable by having differing pharmacological sensitivities to RYR1 agonists. METHODS Expression vector with a mutation in RYR1 corresponding to the Ala4894Thr, Ala4894Pro, Ala4894Ser, or Ala 4894Gly variant of human RyR1 was transfected into human embryonic kidney 293 cells. At 72 hours after transfection, we determined the intracellular Ca(2+) changes induced by caffeine and 4-chloro-m-cresol (4CmC), in the presence or absence of dantrolene. RESULTS Ala4894Thr-transfected cells and Ala4894Ser-transfected cells were more sensitive to caffeine than the wild type, and Ala4894Thr-transfected cells were also more sensitive to 4CmC than the wild type, whereas Ala4894Pro-transfected cells had no response to caffeine or 4CmC. Ala4894Gly-transfected cells were significantly less sensitive to caffeine than the wild type. In addition, the responses of Ala4894Thr-transfected cells and Ala4894Ser-transfected cells to caffeine were suppressed by dantrolene. CONCLUSION We concluded that different Ala4894 variants of RyR1 lead to different agonist/antagonist sensitivities, which may predict differing RYR1 functionality during excitation-contraction coupling and sensitivity to MH. The hypersensitive Ala4894Thr-RyR1 is associated with MH and the poorly functional Ala4894Pro-RyR1 with CNMDU1.
Collapse
Affiliation(s)
- Toshiaki Haraki
- Department of Anesthesiology and Critical Care, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan.
| | | | | | | | | | | |
Collapse
|
22
|
MacLennan DH, Zvaritch E. Mechanistic models for muscle diseases and disorders originating in the sarcoplasmic reticulum. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2011; 1813:948-64. [DOI: 10.1016/j.bbamcr.2010.11.009] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2010] [Revised: 11/11/2010] [Accepted: 11/18/2010] [Indexed: 11/29/2022]
|
23
|
|
24
|
Wolfram F, Morris E, Taylor C. Three-dimensional structure of recombinant type 1 inositol 1,4,5-trisphosphate receptor. Biochem J 2010; 428:483-9. [PMID: 20377523 PMCID: PMC3685215 DOI: 10.1042/bj20100143] [Citation(s) in RCA: 18] [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: 01/25/2010] [Revised: 03/29/2010] [Accepted: 04/08/2010] [Indexed: 11/17/2022]
Abstract
IP3Rs (inositol 1,4,5-trisphosphate receptors) are the intracellular channels that mediate release of Ca2+ from the endoplasmic reticulum in response to the many stimuli that evoke Ins(1,4,5)P3 formation. We characterized and purified type 1 IP3R heterologously expressed in Sf9 insect cells, and used the purified IP3R1 to determine its three-dimensional structure by electron microscopy and single-particle analysis. Recombinant IP3R1 has 4-fold symmetry with overall dimensions of approx. 19.5 nm x 19.5 nm x 17.5 nm. It comprises a small domain, which is likely to include the pore, linked by slender bridges to a large cytoplasmic domain with four petal-like regions. Our structures of recombinant IP3R1 and native cerebellar IP3R have similar appearances and dimensions. The only notable difference is the absence of a central stigma-like domain from the cytoplasmic region of recombinant IP3R1. The first structure of a recombinant IP3R is an important step towards developing three-dimensional structures of IP3R that better contribute to our understanding of the structural basis of IP3R activation.
Collapse
Key Words
- calcium channel
- electron microscopy (em)
- inositol 1,4,5-trisphosphate receptor (ip3r)
- single-particle analysis (spa)
- clm, cytosol-like medium
- ddm, dodecyl maltoside
- ecfp, enhanced cyan fluorescent protein
- em, electron microscopy
- er, endoplasmic reticulum
- ip3r, inositol 1,4,5-trisphosphate receptor
- pbm, phosphate-buffered medium
- peg, poly(ethylene glycol)
- ryr, ryanodine receptor
- spa, single-particle analysis
- tem, tris/edta medium
Collapse
Affiliation(s)
- Francis Wolfram
- *Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, U.K
| | - Edward Morris
- †Section of Structural Biology, Institute of Cancer Research, Chester Beatty Laboratories, London SW3 6JB, U.K
| | - Colin W. Taylor
- *Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, U.K
| |
Collapse
|